28 results about "Central veins" patented technology

The invention discloses a CVC catheter with a central temperature monitoring function, and relates to the technical field of central temperature monitoring and analysis. The CVC catheter is used for monitoring the central vein temperature of a patient, and then the central vein temperature and all treatment-related indexes are combined to monitor the central vein temperature of the patient. The core targets of cooling precision and infusion individualization in the mild hypothermia treatment process are achieved, firstly, the temperature and the flow speed of cold saline water in a heat conduction pipe in the cooling stage of mild hypothermia treatment are obtained through analysis by combining the central vein temperature and all treatment related indexes; meanwhile, the optimal infusion speed is obtained through analysis in combination with the central vein temperature, all treatment related indexes and infusion medicine information, and finally in the sustaining stage of mild hypothermia treatment, the treatment stability condition of a patient is judged by monitoring the vein temperature. According to the application, the central vein temperature is taken as a data basis, a stable reference is provided for mild hypothermia treatment, and the safety, effectiveness and intelligence of mild hypothermia treatment are remarkably improved.

The utility model relates to a central venous indwelling catheter dressing fixing patch which comprises a square dressing body, a window is arranged on the dressing body in a penetrating mode, an elastic cover piece covering the window is detachably arranged on the front side wall of the dressing body, and one end of the elastic cover piece is connected with the dressing body. A through hole for a branch tube of the catheter to pass through is formed in the dressing body and below the window; the upper end of the dressing body is transversely provided with a folding part capable of being folded forwards, the left-right length of the folding part is larger than the left-right width of the dressing body, the middle of the rear side wall of the folding part is provided with a first hook-and-loop fastener female patch, and the left end and the right end of the rear side wall of the folding part are each provided with a first hook-and-loop fastener male patch; when the dressing is used, the branch tube of the catheter penetrates through the through hole and then can be fixed on the dressing body through cooperation of the folding part, the first hook-and-loop fastener female patch and the first hook-and-loop fastener male patch, in addition, hemostatic cotton can be fixed through cooperation of the window and the elastic cover piece, the integrity is good, and operation is convenient.

A system and method automatically detect, in MR images, WM lesions exhibiting a central vein sign. A set of MR images of a brain lesion is acquired, using images of the set as input to different ML algorithms. A first ML algorithm classifies inputted image(s) into first or second classes. The first class includes CVS+ / − and the second class CVSe lesions. A second ML algorithm classifies inputted image(s) into third or fourth classes. The third class includes CVS+ lesions and the fourth central vein sign− lesions. For each set, probability values are used that the set belongs to classes as inputs to a final classifier performing a final classification of the set into second, third, or fourth classes. For each class, the final classifier outputs final probability that the set belongs to the class. The second, third or fourth class with highest probability value is provided through an interface.

The invention relates to the field of medical instruments, in particular to a central vein hybridization stent conveying system which comprises a conveyor and a hybridization stent. The conveyor comprises a sheath core assembly, a sheath tube and a stay wire releaser, and the stay wire releaser comprises a first stay wire and a second stay wire; the hybrid stent comprises a stent and an artificial blood vessel which are separated from each other, and the far end side of the artificial blood vessel and the near end of the stent at least partially coincide in the axial direction; the sheath core assembly is sleeved with the support, and the support is located in the sheath tube. The far end side of the first pull wire is wound and bound on the support. The sheath core assembly is sleeved with the artificial blood vessel, the sheath core assembly is located in the sheath tube, the far-end side of the second pull wire winds and restrains the artificial blood vessel, or the conveyor further comprises a wrapping film, the wrapping film wraps the artificial blood vessel so that the artificial blood vessel can be fixedly arranged on the periphery of the sheath tube in a sleeving mode, and the far-end side of the second pull wire is connected with the wrapping film. By means of the structure, damage to the artificial blood vessel and the stent in the preoperative connection process can be avoided, and meanwhile due to the fact that the connection technology is omitted, the device process of the hybrid stent can be simplified.

The utility model provides a blood sampling device based on a central venous indwelling catheter. According to the blood sampling device, when the blood sampling device leaves a factory, the first end of the three-way connector and the first nipple in the needle cylinder of the first injector form an integrally-formed sealed whole body and cannot be detached; in the process of extracting the mixture by using the first injector before the central venous blood of the patient is extracted by using the second injector, and in the process of injecting the mixture in the first injector into the central vein of the patient through the central vein indwelling catheter after the central venous blood of the patient is extracted by using the second injector; the first injector is not pulled out from the first port, a first nipple of a needle cylinder in the first injector is always isolated from the outside and not exposed to the outside, and the first end of the three-way connector is always isolated from the outside and not exposed to the outside, so that external pollutants can be prevented from being injected into the central vein of a patient, and the patient can be prevented from being polluted. And health and safety threats to patients can be avoided.

The present invention provides a multi-material bionic liver tissue organ chip capable of perfusion culture and a preparation method thereof. The multi-material bionic liver tissue organ chip comprises an upper vascular network module, a bionic liver tissue module, and a bottom vascular network trough module, which are sequentially connected. The upper vascular network module is provided with a perfusion inlet and a first bionic vascular network, and the bottom vascular network trough module is provided with a second bionic vascular network and a perfusion outlet. The bionic liver tissue module comprises an outer shell, within which are disposed N hepatic lobules, where N is greater than or equal to 3. Each hepatic lobule is provided with hepatic lobular connective tissue on the outer side, and a central hepatic lobule vein is provided running through the middle of each hepatic lobule from top to bottom. The first and second bionic vascular networks are provided with bionic central veins and bionic vascular connective tissue corresponding to the central hepatic lobule vein and hepatic lobular connective tissue of each hepatic lobule. The technical solution of the present invention has excellent biocompatibility and meets the requirements of perfusion culture.

Transvascular diaphragm pacing systems (TDPS) and methods are disclosed for providing respiratory therapy to a patient. The TDPS can provide rapid insertion and deployment of endovascular pacing electrodes in critically ill patients who require intubation and invasive PPMV in order to support the physiological requirements of the human ventilatory system. The systems and methods make best use of the contractile properties of the diaphragm muscle and prevent muscle disuse and muscle atrophy. This can be carried out by engaging the phrenic nerves using patterned functional electrical stimulation applied to endovascular electrodes that are temporarily and reversibly inserted in central veins of the patient, such as the left subclavian vein and the superior vena cava. The TDPS can be designed to seamlessly interface with any commercially available positive-pressure ventilatory assistance / support equipment such as is commonly in use in hospital intensive care units (ICU) for treating critically ill patients with breathing insufficiencies, pain, trauma, sepsis or neurological diseases or deficits.

The invention discloses a central vein thrombus monitoring and removing device, and relates to the technical field of thrombus monitoring, the central vein thrombus monitoring and removing device is composed of a monitoring module, an early warning module, a data analysis module and an interaction module, and the monitoring module comprises the following contents: an MEMS sensor is connected to a punctured catheter, and after calibration, the MEMS sensor is connected to the punctured catheter; the central venous pressure, the blood flow velocity and the blood concentration of a patient are monitored, data of the central venous pressure, the blood flow velocity and the blood concentration are recorded, whether an early warning numerical value is reached or not is determined during recording, if yes, an instruction is directly sent to an early warning module, and then the blood flow data are transmitted to a data analysis module and an interaction module; the data analysis module adopts staged data transmission and analysis, the change trend of blood flow data can be accurately captured, abnormal data can be marked and classified, meanwhile, risk factors of thrombus formation can be recognized by comparing and analyzing historical data, and a basis is provided for formulating a personalized treatment scheme.

The invention relates to a hybridization stent conveying system for central veins. The hybridization stent conveying system comprises an outer sheath tube, a handle assembly, an inner sheath core, a pre-cutting tool, a hybridization stent and a tearable sleeve. The handle assembly comprises an outer shell and a transmission part, and the near end of the outer sheath tube penetrates through the outer shell in a sliding mode and is connected with the transmission part; the inner sheath core slidably penetrates through the outer sheath tube, and the near end of the inner sheath core is fixedly connected with the outer shell; the pre-cutting tool is arranged on the inner wall of the outer sheath tube; the intraoperative stent comprises an artificial blood vessel and an intravascular stent which are connected, and the intraoperative stent is arranged on the inner sheath core in a sleeving mode and located between the inner sheath core and the outer sheath tube after being compressed. The far end of the tearable cannula is fixedly connected with the inner wall of the outer sheath tube, and the tearable cannula is arranged on the periphery of the artificial blood vessel in a sleeving mode and constrains the artificial blood vessel after thermal shrinkage. When the transmission part drives the outer sheath tube to move towards the near end, the precutting tool cuts the tearable sleeve, and meanwhile the outer sheath tube drags the tearable sleeve to tear the tearable sleeve. According to the structure, the loading efficiency of loading the hybrid scaffold into the sheathing canal can be improved, and smooth release of the hybrid scaffold in a human body in a subsequent operation can also be ensured.

A surgical operation system comprises an endoscope camera system (901) and a medical device (902), and the endoscope camera system (901) is in direct or indirect communication connection with the medical device (902); the medical equipment (902) comprises a central venous pressure measuring device (903), and the central venous pressure measuring device (903) is used for acquiring central venous pressure data of a patient; the endoscope camera system (901) is used for acquiring an image signal of a to-be-observed part of a patient, generating a visual image of the to-be-observed part of the patient and displaying the visual image; the endoscope camera system (901) is further used for obtaining the central venous pressure data from the medical equipment (902) and displaying the central venous pressure information of the patient based on the central venous pressure data, when a user observes the visual image of the observation part of the patient on the endoscope camera system (901), the central venous pressure information of the patient can be conveniently obtained, and the operation efficiency is improved.

The invention provides a central vein risk hierarchical evaluation system and method based on data fusion. The method comprises the following steps: acquiring a fixed image and a dynamic image; performing interpolation transformation on the dynamic image and calculating a rigid registration value of the fixed image and the transformed dynamic image; performing rigid registration on the fixed image and the dynamic image to obtain an initial registration fixed image and an initial registration dynamic image; constructing an image pyramid and carrying out deformable registration to obtain a target registration fixed image and a target registration dynamic image; based on the target registration fixed image and the target registration dynamic image, respectively extracting anatomical information features and functional information features; and constructing a target three-dimensional anatomical model based on the anatomical information features and the functional information features, performing risk hierarchical assessment on the central vein, and outputting a risk hierarchical assessment result. According to the method, two kinds of non-contrast enhanced sequence image fusion are adopted to fully consider association between anatomical information and functional information, and the reliability of a central vein risk assessment result is improved.

The utility model relates to an infusion filter fixing device, which belongs to the technical field of medical instruments and is used for solving the problems that in the prior art, an infusion filter is not fixed, the neck burden of a patient is increased, a pipeline falls off easily, and an infusion device is disconnected from a central vein. The infusion filter fixing device comprises a pipeline fixing assembly, a filter fixing unit, a limiting assembly and a fixing clamp, the pipeline fixing assembly is connected with the filter fixing unit, the filter fixing unit is of a cavity structure, the limiting assembly is arranged in a cavity of the filter fixing unit, and the fixing clamp is arranged in the cavity of the filter fixing unit. The limiting assembly is used for fixing the position of the infusion filter, and the fixing clamp is connected with the filter fixing unit. The transfusion filter and a pipeline connected with the transfusion filter can be effectively fixed, and the risks that the pipeline is separated and a transfusion device is disconnected from a central vein in the use process of a patient due to the fact that the position of the filter is not fixed are avoided.

The utility model belongs to the technical field of medical instruments, and particularly provides a catheter component and a catheter positioning system.The catheter component comprises a catheter and a fixator, the catheter comprises a first end and a second end, the first end is used for being inserted into a central vein, the catheter is provided with an infusion hole penetrating through the length direction of the catheter, and a guide wire can penetrate through the infusion hole; the fixer is detachably connected with the second end, and the fixer can fix the guide wire. By arranging the fixator connected with the second end, relative fixation of the catheter and the guide wire is achieved, then the relative position relation between the first end of the catheter and the end of the guide wire is effectively controlled, the position of the first end of the catheter can be judged according to the position of the end of the guide wire, and the position of the first end of the catheter in the central vein is effectively controlled; according to the design, the catheter and the guide wire can be synchronously inserted into the central vein as a whole, repeated operation caused by independent insertion of the catheter and the guide wire is avoided, and therefore the operation efficiency of inserting the catheter into the central vein is effectively improved.

The utility model discloses a central vein puncture needle. The central vein puncture needle comprises a puncture needle head, a needle cylinder and a piston push rod assembly, the needle cylinder and the piston push rod assembly are connected in a sliding mode, one end of the needle cylinder is a puncture needle head connecting end and is provided with a connector used for being connected with the puncture needle head, the piston push rod assembly is connected with the needle cylinder in a sliding mode, and an L-shaped pressure measuring tube is arranged on the cylinder wall, close to the puncture needle head connecting end, of the needle cylinder. One end of the L-shaped pressure measuring tube is communicated with the needle cylinder, and a tube cover used for sealing a tube opening is arranged on the tube opening of the other end of the L-shaped pressure measuring tube. According to the central vein puncture needle, the structure of an existing central vein puncture needle is improved, the design that the L-shaped pressure measuring tube is additionally arranged on the injection needle cylinder is adopted, puncture steps can be reduced, whether a vein is accurately punctured or not can be conveniently and rapidly judged, meanwhile, the risk of iatrogenic pollution caused by blood splashing when the central vein puncture needle enters an artery by mistake can be avoided through the arrangement of the filter screen, and safety is improved. And the puncture needle can be repeatedly used in the same puncture process.

The embodiment of the utility model relates to the technical field of measuring bags, in particular to a disposable central venous pressure measuring bag, which comprises a plurality of storage bags for storing appliances required by central venous pressure measurement, and the plurality of storage bags are assembled and combined through a connecting structure; a net bag is fixed in the storage bag, and an elastic band is arranged at the position of a bag opening of the net bag. The central venous pressure measuring bag has the advantages that when the central venous pressure measuring bag is actually used, appliances needed for measuring the central venous pressure are placed in the storage bags in a classified mode, then the storage bags are assembled and combined together through the connecting structures, the central venous pressure measuring bag can be obtained, the whole measuring bag can be directly used when the central venous pressure needs to be measured, and the measuring bag is convenient to use. Required appliances do not need to be configured temporarily, so that the situation of omission caused by short preparation time is avoided; meanwhile, when the storage bags are combined together, the storage bags are arranged according to the sequence of instruments used for measuring the central venous pressure, so that the instruments can be conveniently taken and used according to the operation sequence during actual operation.

The invention discloses application of corydalis saxicola in preparation of a medicine for preventing and treating liver microcirculation disturbance or liver injury caused by lipopolysaccharide. When lipopolysaccharide induction is carried out or 6 hours after lipopolysaccharide induction is carried out; corydalis saxicola bunting injection with corydalis saxicola bunting alkali as active ingredient for intravenous or intramuscular injection, which can reduce the number of leukocytes rolling and adhering to the central vein region of the liver, the level of serum alanine transaminase (ALT) and aspartate transaminase (AST), the necrosis area of the liver tissue, the tumor necrosis factor-alpha (TNF-alpha) of the liver tissue and interferon-gamma (IFN-gamma) of the liver tissue, wherein the number of leukocytes rolling and adhering to the central vein region of the liver is increased due to lipopolysaccharide increase. And content.

The application discloses a liver disease recognition method and system for HE staining pathological whole image. The method comprises the following steps: inputting a preprocessed liver HE staining whole image into an improved SegMoTE segmentation model for segmentation to obtain an effective tissue region; inputting the effective tissue region into the improved SegMoTE segmentation model for segmentation to obtain a portal tract and a central vein; inputting the portal tract into the improved SegMoTE segmentation model for segmentation to obtain an instance segmentation result of an adenocyst structure, calculating corresponding morphological parameters based on the instance segmentation result of the adenocyst structure, and obtaining classification results of vascular endothelitis, bile duct injury and cholangitis through a classifier; inputting the portal tract and a portal tract boundary into the improved SegMoTE segmentation model for segmentation to obtain a contour mask of each nucleus, cutting a nucleus region corresponding to the contour mask into an image block, and inputting the image block into an improved MSAF-Net classification model to obtain a classification result of inflammatory cells. The application improves the recognition accuracy of liver diseases.

The utility model belongs to the technical field of medical treatment and public health, and particularly relates to a novel multifunctional operating bed baffle which comprises an operating bed body, and four connecting columns are fixedly connected to the right side of the operating bed body. When the operating bed main body inclines, the steel balls placed in the storage boxes roll out and fall into the corresponding connecting boxes due to gravity, the steel balls fall downwards, under the action of gravity, the steel balls drive the connecting boxes to move downwards, the connecting boxes drive the operating bed baffle to move through the nylon wire belt, and therefore it is guaranteed that when the operating bed main body inclines, the steel balls are not prone to falling off. The operating bed baffles can be automatically lifted and blocked in front of shoulders or feet of a patient, the pair of operating bed baffles is installed on the operating bed main body, when the operating bed main body inclines, the operating bed baffles are lifted, the body of the patient is prevented from slipping off, the safety of the patient is protected, and after an operation is finished or an anesthetist needs technical operations such as trachea intubation, central vein puncture and sputum suction, the operating bed baffles can be automatically lifted up and blocked in front of the shoulders or feet of the patient. The operating bed is restored, an anesthetist can operate the operating bed without obstacles, and a patient can be transferred conveniently.

The utility model discloses an anti-blocking three-way infusion apparatus. The anti-blocking three-way infusion apparatus comprises a three-way tube body, the three-way tube body comprises a main tube, a branch tube and a three-way knob, the main tube and the branch tube are vertically connected through the three-way knob to form a T-shaped structure, and the interiors of the three-way tube body and the three-way knob are communicated in a T-shaped structure mode. Filter screens are respectively arranged at two ends of the main pipe and the end parts of the branch pipes, and are detachably mounted at the end parts of the main pipe or the branch pipes; the three-way pipe body comprises a first liquid medicine input end and a second liquid medicine input end, and the first liquid medicine input end and the second liquid medicine input end are respectively provided with a pressure sensing column. By arranging the double filter screens, floccules can be prevented from directly entering the central vein, meanwhile, when the pressure of the three-way infusion apparatus is increased due to the fact that the blocking area of the filter screens is gradually increased, the arranged pressure sensing column shifts, nursing personnel can be reminded to replace the corresponding three-way infusion apparatus in time, and the nursing efficiency is improved. Therefore, interruption of fluid infusion or other major clinical adverse events are avoided.

The utility model belongs to the technical field of visual catheters, and particularly relates to a peripheral puncture central vein visual catheter which comprises a connecting frame, the output end of the connecting frame is fixedly connected with an access tube, the input end of the connecting frame is fixedly connected with two butt-joint tubes, the butt-joint tubes are symmetrically distributed, and rubber rings are sleeved outside the butt-joint tubes. The outer portion of the butt joint pipe is in threaded connection with a connector, the interior of the connector is fixedly connected with a connecting pipe, the inner side wall of the butt joint pipe is fixedly connected with a fixing frame, a sealing ring is installed in the fixing frame, and the end of the connector is attached to the sealing ring. According to the utility model, the connectors and the connecting pipes are arranged, so that the connecting pipes and the interiors of the connecting pipes and the butt-joint pipes at the two ends of the connecting frame can be conveniently cleaned and disinfected; and by arranging a limiting block, a compression spring and a limiting shaft, the film covering frame can be conveniently detached and replaced.

The invention discloses an ultrasound-guided central vein minimally invasive catheterization method and device for breast cancer chemotherapy. The method comprises the following steps: acquiring affected side operation and radiotherapy data before catheterization to construct an individualized anatomical risk model; performing three-dimensional scanning on the puncture area, collecting multi-mode blood vessel microenvironment characteristics, generating a fusion image, and identifying a lymphatic vein high-risk area; determining an optimal puncture path through a safety scoring algorithm; in-plane puncture is guided by ultrasound, bio-impedance and blood flow spectrum are monitored synchronously, and automatic early warning is performed when abnormity occurs; the catheter is fed in normally, pressure, position offset and intracavitary electrocardio characteristics are fed back in real time through a microsensor at the far end of the guide wire, and the pushing depth of the catheter is dynamically corrected till the tip end is located on the head side of the junction of the superior vena cava and the right atrium. According to the method, the technical problems of inaccurate catheterization positioning, high complication risk and dependence on radiation caused by anatomical structure variation and complex blood vessel conditions of a breast cancer patient in an ultrasonic guided catheterization method in the prior art are solved.

The utility model discloses a configurable teaching garment for ICU nursing practice, and belongs to the technical field of medical treatment. The device mainly comprises a teaching garment and accessories, anatomical patterns of human ribs are printed on the teaching garment, the surface of the teaching garment is wrapped with hook-and-loop fastener rough surfaces, hook-and-loop fastener hook surfaces are arranged on the back faces of the accessories, and the accessories comprise an electrode patch, a defibrillation plate patch, a central vein patch and a plurality of viscera patches. The electrode slice patch is a circle with the diameter of 2-3 cm, and the electrode slice patch is provided with multiple colors. The defibrillation plate patch is a rectangle of 7.5 * 11 cm. The central vein patch is in a long and thin strip shape. The viscera patch is used for simulating the viscera of a patient, and the viscera patch used for simulating the bronchus and the esophagus is cylindrical. The configurable teaching garment for ICU nursing practice achieves the effect of helping teaching.

The utility model discloses a multifunctional central venous catheter, and relates to the technical field of medical instruments, the multifunctional central venous catheter comprises an outer sleeve internally provided with three cavities, one end of the outer sleeve is fixedly connected with a puncture assembly, the other end of the outer sleeve is provided with a fixing assembly, and one end, close to the puncture assembly, of the outer sleeve is provided with a detection assembly. Through cooperative arrangement of the outer cannula, the main chamber, the main catheter, the one-way valve and other structures, when a pulmonary artery duct or an endocardium temporary pace-making lead needs to be placed in the operation process, the pulmonary artery duct or the endocardium temporary pace-making lead can be pushed into the main catheter, and the end of the pulmonary artery duct or the endocardium temporary pace-making lead is moved into the body of a patient along the main catheter; the problems that the risk of corresponding complications of central vein puncture is increased and a large amount of time is wasted due to the fact that central vein puncture needs to be carried out again when a pulmonary artery catheter or an endocardium temporary pace-making lead needs to be placed in an operation of an existing venous catheter hand are solved as much as possible.

The utility model discloses a fixator for central venous indwelling catheter in the technical field of medical instruments, which comprises an application and a fixing plate, the surface of the fixing plate is rotatably sleeved and connected with a turntable, the outer side surface of the turntable is fixedly provided with a first fixing hole, the outer side surface of the fixing plate is fixedly provided with a second fixing hole, and the first fixing hole and the second fixing hole are communicated with each other. Second fixing bolts are in threaded connection with the interiors of the first fixing holes and the second fixing holes, one end of the central venous indwelling catheter penetrates through the interior of the penetrating hole, one side of the central venous indwelling catheter is placed in the middles of the multiple pressing blocks, release paper is torn open, the bottom of the patch and the surface of the body of a patient are bonded and fixed, then a rotary disc is manually screwed, and the central venous indwelling catheter is fixed to the bottom of the patch. The rotating disc rotates to pressurize one end of a limiting rod through a rotating hole in the surface, so that the limiting rod moves in a limiting hole, the movement of the limiting rod can drive a pressing block to move towards the surface of the central venous indwelling catheter and gradually make contact with the surface of the central venous indwelling catheter, and the effect of limiting and fixing the surface of the central venous indwelling catheter is achieved.

The utility model relates to an external fixing device for a central vein U-shaped catheter, which comprises a fixing patch and a buckle group, and the fixing patch is used for being fixed on the skin of a patient; the buckle sets are fixedly arranged at the two ends of the fixing paster respectively, and the buckles are used for clamping a catheter. A small U-shaped groove is further formed in the end, making contact with the skin outlet, of the fixing patch and used for being matched with the buckle set to fix the catheter at the skin outlet. The fixing paster has the advantages that the fixing paster is simple in structure and convenient to operate, the central venous catheter can be fixed to the fixing paster through the buckle set on the fixing paster, the fixing paster is fixed to the skin of a patient through the exposed pasting layer by tearing off the release paper, and therefore the central venous catheter is fixed; due to the special arrangement of the overall structure of the fixing patch, the catheter between the two points can naturally form a U shape, the catheter is prevented from being disengaged, the exposed end is prevented from being bent, the smoothness of infusion is guaranteed, and the treatment effect is improved.

The utility model relates to hemodialysis technical field especially, it is a kind of pipeline connecting device of immediate wear type artificial blood vessel, including subcutaneous tissue layer, the skin layer of being in the upper layer of subcutaneous tissue layer, the venous blood vessel and arterial blood vessel being arranged between subcutaneous tissue layer and skin layer and the artificial blood vessel being established between venous blood vessel and arterial blood vessel. In the utility model, the original artificial blood vessel structure is improved scientifically and rationally, venous transfusion port, arterial transfusion port, oval puncture bevel and rubber septum are arranged on artificial blood vessel, artificial blood vessel can be embedded between subcutaneous tissue layer and skin layer, and skin puncture hill, which is convenient for puncture needle to puncture and position, can be formed on skin layer, effectively reduce the risk problems such as surgical trauma, puncture risk, catheter infection, central vein stenosis and even occlusion of hemodialysis process of hemodialysis patient, thereby improve the security and stability of actual hemodialysis use.

The present invention relates to a method for isolating a stem cell line derived from a tissue of a primary meristem among leaves of a plant, comprising the steps of: (a) sterilizing at least a portion of a leaf containing a central vein or other veins; (b) incising a central vein or other veins of the leaf to expose primary meristem cells from internal vascular tissue of the central vein or other veins; and (c) culturing cells from said exposed cells, which avoids the difficulty of surface sterilization when using other types of explants, and to stem cell lines obtained using said method.

The invention provides a device for judging the position of a catheter in a central vein, relates to the technical field of medical equipment, and solves the technical problem that in the prior art, the flow speed of normal saline is higher than the moving speed of the tip of the catheter, so that an electric signal is transmitted to an electrocardiogram monitor in advance, and the accuracy of position judgment is influenced. The device is arranged; the conductive device is used for connecting the catheter device and establishing electrical connection with an external electrocardiograph monitor; the guide device and the conductive device form stable electrical connection, and the guide device electrically connects the tip of the catheter device with the conductive device, so that the position of the tip of the catheter device is determined according to a wave value displayed by an electrocardiograph monitor in the puncture process of the catheter device; according to the highest peak point of the P wave value, it is determined that the catheter tip position reaches the superior vena cava and right atrium junction (CAJ), it is ensured that the flow speed of normal saline is matched with the movement speed of the catheter tip, and the problem that due to the too high flow speed of normal saline, an electric signal is transmitted to an electrocardiogram monitor in advance is solved.