1841 results about "Thrombus" patented technology

The invention discloses a thrombus excision system. An embolus is extracted through a mechanical embolus extraction device, a blood vessel is dredged, and revascularization of the blood vessel is achieved. A saccule guide catheter is put at the near end of the embolus part when the embolus is extracted, blood flow is temporarily blocked, and thus a fine crushed embolus generated in the embolus extraction process is prevented from being flushed to the far end of the blood vessel; meanwhile, for a relatively large embolus, a part of thrombus can also be sucked by virtue of the saccule guide catheter, and then the residual thrombus can be extracted by virtue of a thrombus exsector. The thrombus exsector, the saccule guide catheter and a delivery microcatheter are arranged on the thrombus excision system disclosed by the invention, wherein the thrombus exsector is used as a main component, an excision spring is arranged, and the release state of the excision spring is a conical spiral state. Compared with the prior art, the thrombus excision system has the advantages that the thrombus exsector is very soft, the minimal through size is 0.014' (0.36mm), the thrombus exsector can easily enter a cerebral vessel, a near-end protection technology is adopted in the operation process, and thrombus suction is combined with mechanical embolus extraction, so that the success rate of the operation is improved, and the complications are reduced.

Described herein are systems, devices, and methods for methods for autologous blood transfusion. For example, an apparatus may comprise a fluid conduit configured to receive a volume of fluid from a patient and a container fluidically coupled to the fluid conduit. The container may define a reservoir configured to receive the volume of fluid from the fluid conduit. The apparatus may include a vacuum conduit couplable to a vacuum source, a vent configured to vent air into the reservoir, and at least one valve configured to couple the reservoir to the vacuum conduit to generate negative pressure within the reservoir such that the volume of fluid is drawn into the reservoir, and decouple the reservoir from the vacuum conduit while coupling the reservoir to the vent such that air is vented into the reservoir at an average rate that prevents turbulent movement of the volume of fluid within the reservoir.

The present invention discloses a prosthetic heart valve comprising at least two valve components, a sealant covering the valve components, and an edge-sealing structure. A space is formed between the valve components covered with the sealant. The edge-sealing structure has a closed end face and connects the ends of the sealant to form a closed space within the space. The prosthetic heart valve provided by the present invention can reduce the risk of thrombosis between the valve components. Because the edge-sealing structure is flexible, it has little effect on the compression and gripping of the prosthetic valve, and the addition of the edge-sealing structure does not affect the normal function of the prosthetic valve.

The invention relates to a spontaneous cerebral hemorrhage postoperative intermuscular venous thrombosis risk prediction system based on a molecular mechanism and multi-modal data and a use method thereof, image space features are extracted through a multi-modal data level CNN to be complementary with time sequence features captured and detected by Transform, and support is provided for blood coagulation-endothelium-fibrinolysis three-channel activation degree calculation; a knowledge graph alignment module of a pathology and data level maps the cross-modal features to a unified semantic space, and corrects data conflicts with pathology time sequence constraints; and channel-space-time triple attention linkage at a space-time level is carried out, and a high-risk area is accurately marked. In a path driving layer, three-path activation degrees cooperatively adjust a dynamic time window, a single-path standard-exceeding triggering monitoring interval is shortened, and a double-path standard-exceeding amplitude is multiplied; and in a closed-loop feedback layer, system parameters are updated through confidence, pathological probability and conflict signal recursion, real-time calibration of a pathological mechanism and data is realized, and thrombus risk prevention and control efficiency is comprehensively improved.

A method of extracting a thrombus from a thrombus site in a cerebral artery of a patient by advancing a first catheter into an internal carotid artery of the patient; advancing a funnel catheter within the first catheter; moving the funnel catheter and the first catheter with respect to each other to place the funnel outside of the first catheter; expanding the funnel into contact with an inner wall of the internal carotid artery at or proximal to a distal end of a carotid siphon, thereby reducing blood flow past the funnel; advancing a clot-mobilizer distally through the first catheter toward the thrombus and beyond the carotid siphon; engaging thrombus material from the thrombus with the clot-mobilizer; moving the clot-mobilizer and thrombus material proximally at least partially into the funnel; applying suction to aspirate thrombus material; and moving the funnel, the clot-mobilizer and the thrombus material proximally within the vasculature.

The invention discloses a venous thrombosis risk assessment method based on a large language model, and relates to the technical field of medical artificial intelligence, and the method comprises the steps: collecting thoracic surgery diagnosis and treatment data of a patient, carrying out the space-time alignment, generating a standard diagnosis and treatment data flow, and carrying out the homomorphic encryption of the standard diagnosis and treatment data flow, and forming an encrypted patient data package; inputting the encrypted patient data packet into a multi-task large language model, performing feature extraction and semantic coding by a feature coding layer, performing time sequence modeling and risk probability calculation by a risk quantification layer, and outputting a venous thromboembolism risk level of a patient; and performing feature decoupling and potential space mapping on the encrypted patient data packet to obtain thrombus semantic potential features. Through the multi-task large language model, the dual machine learning algorithm and the homomorphic encryption, the accuracy of venous thrombosis risk early warning is improved, and the safety of the risk assessment process is enhanced.

Disclosed herein are clot treatment systems including mechanical thrombectomy devices and clot treatment devices, and associated devices and methods. In some embodiments, a method of removing clot material from a blood vessel of patient includes inserting a catheter to proximate the clot material within the blood vessel while radially constraining a clot treatment device and an embolic protection device within the catheter. The method can further include moving the catheter proximally to deploy the clot treatment device at least partially distal to clot material within the blood vessel, and then moving the catheter further proximally to deploy the embolic protection device at least partially proximal to the clot material. The clot treatment device can include one or more relief features configured to release captured clot material if the force on the clot treatment device exceeds a threshold.

The invention relates to a deep vein thrombectomy support device which has the advantage of being convenient to clean. The inner tube assembly comprises an inner tube, a conical head assembly and a limiting key, the inner tube and the handle assembly are matched in the mode that the inner tube can slide axially but cannot rotate relative to the circumferential direction, the conical head assembly is arranged at the far end of the inner tube, the limiting key is movably installed on the handle assembly, and the limiting key selectively acts on the inner tube; the middle tube assembly comprises a middle tube and a support fixing assembly, the near end of the middle tube is connected to the handle assembly, and the far end of the middle tube is connected with the support fixing assembly; the outer pipe assembly comprises an outer pipe which can be axially and movably arranged on the middle pipe in a sleeving manner; the thrombectomy stent assembly comprises a self-expansion stent and a woven mesh, the near end of the self-expansion stent is connected with the stent fixing assembly, the near end of the woven mesh is connected to the far end of the self-expansion stent, and the far end of the woven mesh is connected to the conical head assembly.

The invention discloses a lower limb vein thrombus formation risk prediction method based on machine learning. The method comprises the following steps: step 1, constructing a triaxial thrombus evolution dynamic container space; 2, generating a pre-thrombus micro-state orbital chain; 3, determining a thrombus formation critical mutation window; 4, introducing a causal stem budget at the thrombus formation critical mutation window, and constructing a natural evolution path and a controlled path; step 5, obtaining an orbit offset difference value; 6, calculating a dynamic orbit stability index; 7, inputting the pre-thrombus micro-state orbit chain and the dynamic orbit stability index into the improved PatchTST model, and introducing a flow continuity regulation operator into a reconfiguration module to obtain a corrected orbit stability index; and 8, outputting a thrombus formation risk prediction result. According to the method, the thrombus formation risk prediction is realized by constructing a triaxial thrombus evolution dynamic container space and combining a mental structure differential equation model and an improved PatchTST model.

Systems and methods for removal of thrombus from a blood vessel in a body of a patient are disclosed herein. The method can include: providing a thrombus extraction device including a proximal self-expanding member formed of a unitary fenestrated structure, a distal substantially cylindrical portion formed of a net-like filament mesh structure, and an inner shaft member connected to a distal end of the net-like filament mesh structure; advancing a catheter constraining the thrombus extraction device through a vascular thrombus, deploying the thrombus extraction; retracting the thrombus extraction device to separate a portion of the thrombus from the vessel wall and to capture the portion of the thrombus within the net-like filament mesh structure; and withdrawing the thrombus extraction device from the body to remove thrombus from the patient.

Systems and methods for removal of thrombus from a blood vessel in a body of a patient are disclosed herein. The method can include: providing a thrombus extraction device including a proximal self-expanding member formed of a fenestrated structure, a substantially cylindrical portion formed of a net-like filament mesh structure having a proximal end coupled to a distal end of the fenestrated structure; advancing a catheter constraining the thrombus extraction device through a vascular thrombus, deploying the thrombus extraction device by stacking a portion of the net-like filament mesh structure outside of the catheter by distally advancing the self-expanding member until the self-expanding member is beyond a distal end of the catheter; retracting the self-expanding member to unstack the portion of the net-like filament mesh structure and to capture the portion of the thrombus; and withdrawing the thrombus extraction device from the body.

Disclosed herein are clot treatment systems including mechanical thrombectomy devices and clot treatment devices, and associated devices and methods. In some embodiments, a method of removing clot material from a blood vessel of patient includes inserting a catheter to proximate the clot material within the blood vessel while radially constraining a clot treatment device and an embolic protection device within the catheter. The method can further include moving the catheter proximally to deploy the clot treatment device at least partially distal to clot material within the blood vessel, and then moving the catheter further proximally to deploy the embolic protection device at least partially proximal to the clot material. The clot treatment device can include one or more relief features configured to release captured clot material if the force on the clot treatment device exceeds a threshold.

The utility model relates to the technical field of medical instruments, in particular to a blood vessel negative pressure thrombectomy device. The blood vessel negative pressure thrombectomy device comprises a negative pressure connecting pipe, a negative pressure suction device and a collecting pipeline, one end of the negative pressure connecting pipe is provided with a pipeline rotating connector, the other end of the negative pressure connecting pipe is connected with an inlet of the negative pressure suction device, one end of the collecting pipeline is connected with an outlet of the negative pressure suction device, and the other end of the collecting pipeline is connected with a pipeline rotating connector. And the negative pressure suction device is used for extracting the medium through the negative pressure connecting pipe and sending out the medium through the collecting pipeline. The thrombus aspirator has the advantages that the thrombus aspirator is simple and reasonable in structural design, thrombus can be effectively and rapidly extracted, operation is flexible, the negative pressure aspirator can freely rotate relative to a catheter entering a blood vessel for thrombus extraction due to the arrangement of the pipeline rotating connector, and a doctor can conveniently adjust the optimal operation direction in vitro.

The invention discloses a sublingual collateral feature extraction and pathological analysis system and method, and relates to the technical field of traditional Chinese medicine tongue diagnosis. Dynamic pressure is applied to the sublingual through a miniature ultrasonic array arranged in a tongue depressor, and meanwhile, an annular polarization multispectral light source is started; an ultrasonic echo signal, a photoacoustic pressure wave and an anti-reflection multispectral image are collected to generate a time-space synchronous fusion data set, and further through a compressed sensing reconstruction algorithm, a biomechanical feedback engine, an acousto-optic thrombus analysis module and the like, the thrombus is reconstructed. According to the four-dimensional pathological risk assessment map generation method and system, the limitation of traditional static detection is overcome, dynamic coupling assessment of blood vessel biomechanical characteristics and thrombosis is achieved, and the risk assessment map generation method and system have the advantages of being high in accuracy, high in accuracy and high in reliability. And the clinical applicability and the diagnosis efficiency of sublingual vein analysis are remarkably improved.

Disclosed herein are clot treatment systems including mechanical thrombectomy devices and clot treatment devices, and associated devices and methods. In some embodiments, a method of removing clot material from a blood vessel of patient includes inserting a catheter to proximate the clot material within the blood vessel while radially constraining a clot treatment device and an embolic protection device within the catheter. The method can further include moving the catheter proximally to deploy the clot treatment device at least partially distal to clot material within the blood vessel, and then moving the catheter further proximally to deploy the embolic protection device at least partially proximal to the clot material. The clot treatment device can include one or more relief features configured to release captured clot material if the force on the clot treatment device exceeds a threshold.

The invention discloses a deep venous thrombosis early warning method and system based on multi-modal physiological signals, and relates to the technical field of health monitoring. The method is used for realizing thrombus early recognition and graded early warning. The method comprises the following steps: synchronously acquiring physiological signals of lower limbs on two sides through a multi-modal sensing device, performing motion artifact elimination and signal quality screening, and generating preprocessed time sequence data; performing dynamic time warping and feature extraction on the time series data, calculating a bilateral symmetry index and an instantaneous and accumulated time-varying difference degree, and fusing the bilateral symmetry index and the instantaneous and accumulated time-varying difference degree with absolute physiological parameters to form a comprehensive risk assessment vector; establishing a dynamic baseline based on the historical risk vector, calculating a current deviation index, and recognizing an abnormal state in combination with a double-side cooperation mode; and according to the deviation index and the duration, in combination with the abnormality type and the severity, generating a graded early warning signal containing a risk grade and a disposal suggestion through multi-stage judgment, thereby realizing early warning and risk management of thrombus.

The invention provides a multi-module collaborative clinical blood coagulation function intelligent evaluation and drug recommendation system, and relates to the technical field of medical information processing. Comprising a data acquisition and fusion module, a state recognition module, a drug intervention effect evaluation module, a decision recommendation module and a system visualization module. According to the system, continuous integration of clinical scattered data is realized by constructing a unified time sequence structure of multi-source detection indexes and medication records; generating a blood coagulation state vector containing the bleeding risk and the thrombus risk through a state recognition mechanism combining rule judgment and data calculation, outputting a confidence score and an index contribution degree, and forming a state track evolving along with time; performing causal evaluation on the difference of the state change before and after intervention to obtain a drug average treatment effect; and individualized drug suggestion or early warning information is generated based on the state track and the intervention effect. And dynamic evaluation and drug intervention measurement and calculation of the blood coagulation risk are realized.

The invention discloses a TAVR postoperative blood flow parameter complementing method based on CT-MRI fusion, and belongs to the technical field of crossing of medical image processing and computational fluid mechanics. A CT valve frame registration technology is adopted, an invisible artificial valve leaflet three-dimensional structure is reconstructed through valve frame information in a CT image and is coupled with a dynamic heart model, a complete valve mechanical and functional simulation platform is constructed, the problem of an imaging blind area is solved, hemodynamic parameters of an inlet and an outlet of a postoperative area are further collected in combination with 4D Flow MRI, and the artificial valve leaflet three-dimensional structure is obtained. The blood flow conditions of the upstream and the downstream of the artificial valve area at each stage of contraction and relaxation of the TAVR postoperative part are comprehensively restored, the temporal-spatial resolution and the physical authenticity of the boundary condition in fluid-solid coupling simulation are greatly improved, and the more real passive response of the valve leaflet under the action of the blood flow is obtained; and a reliable basis is provided for quantitative and mechanical risk analysis of postoperative complications such as thrombosis, perivalvular leakage and valve leaflet fatigue.

The utility model discloses a thrombus aspiration plugging sheath system based on a special-shaped cavity, which comprises a vacuum device, an aspiration plugging sheath, an aspiration plugging sheath and an aspiration plugging sheath, and is characterized in that the vacuum device comprises a negative pressure needle cylinder and a piston buckle arranged on the side wall of the negative pressure needle cylinder; the balloon sheath tube comprises a tube body, a balloon used for blocking is arranged at the far end of the tube body, a connector connected with the vacuum device is arranged on the side of the near end of the tube body in a supporting mode, and a plurality of special-shaped cavities are formed in the tube body; the thrombus dragging instrument is used for blocking blood flow to reduce blood loss during thrombus suction and intercepting the thrombus to prevent the thrombus from escaping when the thrombus is dragged; the vacuum device is arranged on the side branch of the near end of the balloon sheath tube, and the thrombus dragging instrument is arranged in the balloon sheath tube. According to the embodiment of the utility model, the balloon filling opening and the thrombus suction opening are formed in the catheter body, a multi-cavity structure is adopted, the balloon sheathing canal blocks blood flow, and the thrombus dragging instrument is matched with a vacuum device to suck, drag and take out thrombus.

The invention particularly relates to a thrombectomy device, which comprises a capturing bracket, one end close to the far end of the capturing bracket is connected with a far-end spring, and one end close to the near end of the capturing bracket is connected with a pushing guide wire; the capturing bracket is formed by weaving a plurality of groups of weaving wires; one end of the thrombus breaking support is connected with one end, close to the far end, of the capturing support, and the other end is connected with one end, close to the near end, of the capturing support through a flexible wire; the thrombus breaking bracket is arranged in the capturing bracket; the flexible wires are straight wires or wavy wires; when the capturing support moves towards the near end, the thrombus breaking support moves along with the capturing support, elastically deforms and cuts thrombus located in the capturing support. The flexible wire can drive the thrombus breaking support to shake, and the thrombus breaking support in the shaking state has a better cutting effect on thrombus located in the capturing support. The metal coverage rate of the end, close to the far end, of the thrombus extraction device is increased through cooperation of the capturing support and the thrombus breaking support, and small thrombus is prevented from escaping towards the far end.

The invention discloses a medical image segmentation method and system for an aortic dissection true cavity, an aortic dissection false cavity and an aortic dissection false cavity thrombus. The method comprises the following steps: firstly, acquiring three-dimensional medical image data of the aortic dissection, performing preprocessing operation on the image data to obtain a two-dimensional slice image, and performing local region division on the two-dimensional slice image; secondly, performing feature extraction on the divided image through a hierarchical feature extraction module; then, a dynamic region self-adaption module is used for carrying out region adjustment on the extracted feature map, a region response map is generated through a guide path, and explicit adjustment weights are given to different space regions in the feature map; and finally, uniformly aggregating the multi-scale feature maps after region adjustment, outputting a segmentation mask through a prediction module, and generating a segmentation result with a clear structural boundary and complete semantics. According to the method, while the recognition precision of the complex anatomical structure is improved, the detection capability and boundary sensing performance of a small-size focus are enhanced, and the method has good universality and stability.

The invention provides a medical stent and a preparation method thereof.The preparation method comprises the steps that an anti-coagulation coating is arranged on at least part of the surface of the medical stent through physical coating, then an anti-hyperplasia coating is arranged on at least part of the surface of the medical stent through physical coating, the anti-coagulation coating comprises a copolymer, and the anti-hyperplasia coating comprises an anti-hyperplasia coating. A copolymer in the anticoagulant coating contains a zwitterionic unit and an adsorption unit, and the anti-hyperplasia coating contains an anti-hyperplasia drug and a degradable polymer; or, an anti-hyperplasia and anti-coagulation integrated coating is arranged on at least part of the surface of the medical stent through physical coating, the integrated coating contains a copolymer and an anti-hyperplasia drug, and the copolymer in the integrated coating contains a zwitter-ion unit, an adsorption unit and a degradable unit; the adsorption unit is an ester unit containing a carbon-carbon double bond, and the degradable unit is a 2-methylene-1, 3-dioxane unit. The problem that thrombus and restenosis exist at the same time after the stent is implanted can be solved, the binding force between the coating and the substrate is improved, and the falling risk of the coating is reduced.

The invention provides application of active decapeptide in preparation of a medicine for preventing or treating cerebral apoplexy, and belongs to the technical field of biological medicine, the active decapeptide with the amino acid sequence as shown in SEQ ID NO.1 is applied to prevention or treatment of cerebral apoplexy for the first time, the active decapeptide can effectively inhibit formation of cerebral thrombosis of zebra fish with ischemic cerebral apoplexy, and the active decapeptide can be used for preventing or treating cerebral apoplexy. The brain blood flow supply is recovered; meanwhile, the active decapeptide can significantly reduce the hemorrhagic area and hemorrhagic rate of the zebra fish brain with hemorrhagic stroke, repair brain vascular injury and inhibit the occurrence and development of hemorrhagic stroke. In addition, the active decapeptide has small toxic and side effects, and is of great significance for improving the clinical curative effect of cerebral apoplexy and reducing the medication risk when being used for research and development of novel drugs for resisting cerebral apoplexy.

The invention relates to the field of medical information technology and medical data analysis, in particular to a VTE risk prediction method and system based on multi-modal data fusion and dynamic risk modeling, and the system comprises a first feature extraction module, a second feature extraction module, a two-stage risk assessment module and a final risk judgment module. According to the application, through integration of clinical diagnosis and treatment, iconography and genomics data, a deep learning algorithm, a dynamic weight adjustment mechanism and a graph neural network technology are utilized to realize accurate prediction of the VTE risk of the active-stage lung cancer patient. And meanwhile, the problem of cross-mechanism data distribution difference is solved by adopting transfer learning, and the generalization ability of the model is improved. The method can significantly improve the prediction accuracy, reduces the manual intervention demands, and optimizes the medical resource distribution efficiency.

The invention belongs to the technical field of intelligent medical treatment, and provides a stretch sock for preventing lower limb venous thrombosis, comprising: a wrapping body having a pressure layer located on the outer side, a contact layer located on the inner side, and a functional layer located between the pressure layer and the contact layer; the physiological index sensor is arranged on the functional layer and used for collecting physiological index data of the user; the stimulating electrode is arranged on the contact layer, is in contact with the skin of the user and is used for stimulating muscles of the user; the controller is connected with the physiological index sensor and the stimulating electrode and used for receiving the physiological index data and generating a control signal of the stimulating electrode based on the physiological index data and the user baseline data so as to control the stimulating electrode to execute the stimulating parameters corresponding to the control signal. According to the stretch sock for preventing the lower limb venous thrombosis, personalized stimulation can be carried out based on the personalized physiological indexes of the current wearing user, and the prevention effect of the lower limb venous thrombosis is improved.

Provided are an siRNA which inhibits plasma coagulation factor XI gene expression, a pharmaceutical composition containing the siRNA, a conjugate, a reagent kit, and a use of the siRNA, the pharmaceutical composition thereof and the conjugate in preparing a drug used for treating and / or preventing thrombotic diseases and ischemic strokes.

The invention provides a multifunctional intelligent anti-thrombus PICC (peripherally inserted central catheter) for tumor chemotherapy, which comprises a catheter body, a catheter tip, a main infusion cavity, a first auxiliary cavity and a second auxiliary cavity, and the first auxiliary cavity and the second auxiliary cavity are arranged around the main infusion cavity to form a spiral structure; a micro pressure sensor array is embedded in the pipe wall of the first auxiliary cavity; a biological impedance measuring electrode pair is embedded in the pipe wall of the second auxiliary cavity; and the micro pressure sensor array, the biological impedance measuring electrode pair, the micro ultrasonic transducer and the temperature sensor are connected with a processor. According to the method, active thrombus prevention is achieved, passive treatment is changed into active prevention through a triple mechanism, and the thrombus occurrence rate is greatly reduced; meanwhile, the tube body is formed by mutually winding, fusing and extruding three independent cavities (a main infusion cavity, a first auxiliary cavity and a second auxiliary cavity) like a DNA double helix (triple helix is provided herein); and the mechanical stimulation and damage to the inner wall of the blood vessel are reduced.

The invention discloses a deep vein thrombosis risk early warning health information system based on dynamic negative pressure monitoring and AI, and relates to the technical field of intelligent medical health information. Comprising a dynamic negative pressure sensor module, a multi-modal data acquisition module, a waveform primitive analysis module, a hierarchical attention fusion module, a risk assessment classifier module and an early warning output module. The dynamic negative pressure sensor module is used for continuously collecting dynamic negative pressure signals of the lower limbs of the user. According to the dynamic negative pressure monitoring and AI deep vein thrombosis risk early warning health information system, the problem of multi-source heterogeneous physiological data fusion is solved; an original dynamic negative pressure signal is converted into a symbolized primitive sequence with clear physiological significance, so that the data quality is fundamentally improved; according to the method, adaptive fusion of multi-modal data and accurate focusing of key time slices are realized, the specificity and robustness of a risk assessment model are improved, and a false alarm phenomenon caused by physiological activity interference is reduced.

The utility model discloses a rat thrombus forming device which comprises a blood collecting assembly and a thrombus forming assembly, the blood collecting assembly is used for collecting blood of a rat, and the blood collected by the blood collecting assembly is conveyed to the thrombus forming assembly to prepare thrombus; the blood sampling assembly comprises a bottom plate and a top plate, the top plate is located over the bottom plate, a vertical supporting rod is connected between the center of the bottom plate and the center of the top plate, the top plate can rotate around the supporting rod, a plurality of round holes are formed in the top plate in the annular direction, and blood collecting pipes are vertically placed in the round holes; a liquid outlet is formed in the bottom of the blood collecting pipe, a blood transfer pipe is connected to the liquid outlet, and the head end of the blood transfer pipe extends to the thrombus forming assembly; the thrombus forming assembly comprises a rectangular forming groove, a forming template made of rubber is fixed to the bottom of the forming groove, pits with honeycomb holes are densely distributed in the forming template, the diameter of each pit is 2-3 mm, and the depth of each pit is 2-3 mm.

The invention provides an application of catalase nanoparticles in preparation of a medicine for preventing or treating thrombus. A method for preparing the catalase nanoparticles comprises the following steps: 1) reacting dopamine with melanin to generate melanin modified by the dopamine; 2) preparing catalase with carboxyl activated by EDC; and 3) in the presence of NHS, mixing the melanin modified by dopamine with the catalase with carboxyl activated by EDC, stirring overnight, then adding amino methoxy polyethylene glycol (mPEG-NH2), and continuing to react for 3 hours to obtain a product, namely the melanin-dopamine-catalase nanoparticles. The catalase nanoparticles provided by the invention can maintain the biological activity of melanin and catalase for a long time, and can avoid the risk of bleeding when preventing or treating thrombus.