19 results about "Ca2 concentration" patented technology

The invention discloses an electrical stimulation type nerve regeneration method based on calcium signal regulation and control, and relates to the technical field of electrical stimulation type nerve regeneration, and the method comprises the following steps: based on a Schwann cell population calcium signal response feature set, identifying whether the calcium ion concentration is in a microliter stage which breaks through a lowest activation threshold and does not reach a stable state; judging whether the target nervous tissue is in a calcium signal activation critical state or not based on the behavior mode change of the Schwann cell population; based on the judgment result of the calcium signal activation critical state, an electrical stimulation adjustment control instruction is generated in real time in combination with the calcium ion concentration fluctuation trend and Schwann cell population response characteristics, and the calcium ion concentration stability is optimized and the activation state is maintained by adjusting the electrical stimulation intensity, the electrical stimulation pulse width, the electrical stimulation waveform type and the electrical stimulation application time sequence. According to the method, the problem that a calcium signal is difficult to recognize and dynamically optimize in a microliter stage is solved, and precise maintenance of Schwann cell activation and improvement of nerve regeneration efficiency are realized.

The invention discloses a method for establishing a cell line by serum-free culture of PGCs (Primordial Germ Cells) of breeding poultry, the cell line is prepared by blending calcium-free DMEM (Dulbecco Modified Eagle Medium), water and Knockout-DMEM, the cell line is more suitable for osmotic pressure and calcium ion concentration required by proliferation of the PGCs of the breeding poultry, various components of serum-free culture are perfected by using fresh egg white, and the cell line is more suitable for proliferation of the PGCs of the breeding poultry. The combination of growth factors required by primordial germ cells is optimized by adding the FGF-1, so that 100% of cell line establishment efficiency and rapid growth of cells from reproduction crescent, blood and gonad tissues of chicken embryos are realized, and a technical basis is provided for poultry frozen breed conservation, stem cell propagation and gene editing operation.

The utility model discloses a hemostasis assist device for vascular surgery, which relates to the technical field of medical instruments, and comprises a fixing mechanism, a vascular surgery hemostasis mechanism is arranged in the fixing mechanism, the vascular surgery hemostasis mechanism comprises a knob, and the bottom of the knob is fixedly connected with a threaded column. According to the hemostasis mechanism for the vascular surgery department, during hemostasis, the periphery of a wound can be heated through the heating block across the replacement pad, the temperature of the periphery of the wound reaches 37-42 DEG C, activation of platelets can be accelerated to a certain extent at the temperature, energy metabolism of the platelets is accelerated within the temperature range, and the blood circulation is accelerated. The increase of the concentration of calcium ions in the blood platelets is an important signal of platelet activation, and the increased concentration of the calcium ions can promote the activation of glycoprotein receptors on platelet membranes, so that the binding capacity of the blood platelets and fibrinogen is enhanced, the aggregation of the blood platelets is accelerated, and the hemostasis speed is accelerated.

The present invention relates to a structure for a biosensor, a biosensor including the same, and a method for real-time nicotine analysis in saliva using the biosensor. According to the present invention, a structure connected to an electrode of a biosensor forms a structure of a crystalline carbon membrane / calcium ion-selective membrane / TRPA1-containing nanovesicle. When nicotine is contained in saliva containing calcium ions, the nanovesicle having a TRPA1 ion channel in the outermost layer of the structure specifically reacts with the nicotine contained in the saliva to introduce calcium ions. The resulting change in calcium ion concentration changes the surface potential of the crystalline carbon membrane in contact with the calcium ion-selective membrane through the calcium ion-selective membrane. By measuring the change in electrical conductivity, such as the change in open-circuit voltage, nicotine can be detected even in minute amounts of 1 pM, thereby allowing for the quantitative determination of the nicotine concentration in a smoker's saliva in real time.

The invention discloses a preparation method of a coronary artery microcirculation disturbance animal model, and belongs to the technical field of biological medicine. According to the method, the stable mouse CMD model can be established by injecting 20-40 [mu] g / mL Calcimycin into the cardiac apex for the first time. Calcimycin is a calcium ion (Ca < 2 + >) carrier commonly used in a laboratory and can transport calcium ions outside cells into the cells, so that the concentration of the calcium ions in the cells is increased. Particularly, when 40 [mu] g / mL of Calcimycin is injected, the pathological severity of the Calcimycin is further aggravated, myocardial fiber arrangement is disordered, boundary is unclear, a large number of myocardial cells are necrotic and dissolved, cavitation is formed, vascular wall degeneration swelling is caused, inflammatory cell infiltration is caused, and thrombus is formed in microvessels.

The invention provides a method for extracting CD45 positive T cells of mouse placenta decidua and application of the CD45 positive T cells, and belongs to the technical field of tissue cell separation methods.According to the method for extracting the CD45 positive T cells of the mouse placenta decidua, digestive juice and calcium ions with the specific composition are used for the mouse placenta decidua, the concentration of type II collagenase is 0.4-0.6 mg / mL, the concentration of DNaseI is 0.08-0.12 mg / mL, and the concentration of type II collagenase is 0.1-0.5 mg / mL. The concentration of calcium ions is 0.1 to 0.3 mg / mL; then obtaining a cell layer by using a density gradient centrifugation method; carrying out flow cytometry sorting to obtain a CD45 positive cell subset; the extraction efficiency is high, the extracted and separated mouse placenta decidua CD45 positive T cells are small in damage and high in activity, and the extraction method is simple and suitable for industrial application.

In reverse osmosis membrane treatment of water to be treated that contains calcium ions and at least one of fluoride ions and sulfate ions, the decrease in water recovery rate is suppressed and scale formation is suppressed without using a scale dispersant. [Solution] This method includes a reverse osmosis membrane treatment step in which water to be treated, which contains calcium ions and at least one of fluoride ions and sulfate ions, is treated using a reverse osmosis membrane, wherein the calcium ion concentration in the concentrated water is 30 mg / L or less, or the fluoride ion concentration is 30 mg / L or less and the sulfate ion concentration is 100 mg / L or less, the ionic product of the calcium ions and fluoride ions in the concentrated water is equal to or greater than the solubility product of calcium fluoride, or the ionic product of the calcium ions and sulfate ions is equal to or greater than the solubility product of calcium sulfate, and the shear flux on the primary side of the reverse osmosis membrane is adjusted to a range of 0.04 m / sec or more and 0.30 m / sec or less.

The invention discloses a calcium ion concentration prediction method, device and equipment for a CRRT patient and a medium, and relates to the technical field of computers. The method comprises the following steps: acquiring multi-source time sequence observation data of a target CRRT patient, and preprocessing the multi-source time sequence observation data to obtain target time sequence observation data; extracting each historical time sequence associated with the calcium ion concentration from the target time sequence observation data; and determining a target predicted value of the calcium ion concentration, a target confidence interval corresponding to each target predicted value and a target explanatory variable based on each historical time sequence. According to the scheme provided by the invention, the problems that the calcium ion concentration cannot be predicted in real time depending on artificial experience and the prediction uncertainty quantization and interpretability are lacked can be solved, and the calcium ion concentration of the CRRT patient can be accurately predicted in real time.

The invention discloses a shaft pressure prediction method and system in the well killing fluid injection process, and belongs to the technical field of oil exploitation. According to the initial concentration of calcium ions in well killing fluid and the calcium ion concentration analytic solution, the time-varying value of the concentration of other ions in the well killing fluid is determined; according to the calcium ion concentration analytic solution and the time-varying value of the concentration of other ions in the kill fluid, a function that the density of the kill fluid changes along with time in the injection process is fitted, the real-time density of the kill fluid is determined, by establishing a wellbore pressure calculation model considering the density time-varying effect, wellbore pressure values corresponding to different times are predicted, and the real-time density of the kill fluid is calculated. Therefore, the space-time decay rule of the wellbore pressure is obtained. According to the method, the real-time density of the well killing fluid is determined, a density decay model and a pressure calculation model are coupled, and a wellbore pressure calculation model considering the density time-varying effect is established, so that the chained influence of the performance decay of the well killing fluid on the wellbore pressure environment can be clearly described, and the space-time decay rule of the wellbore pressure is obtained.

The present invention belongs to the technical field of landfill leachate treatment, and specifically relates to a method for treating and utilizing high-calcium leachate nanofiltration concentrate. A three-stage ultrafiltration system is mainly used to separate and concentrate the nanofiltration concentrate at a high multiple, and a gypsum crystallization precipitation and divalent ion control system are used to efficiently remove the high-concentration calcium in the secondary ultrafiltration retentate containing scale inhibitors and the secondary ultrafiltration permeate without scale inhibitors and the tertiary ultrafiltration permeate formed during the process. 2+ and SO4 2‑ , and combined with the nanofiltration system to achieve the purpose of closed-loop treatment of high-calcium leachate and nanofiltration concentrate and utilization of humic acid resources. In order to effectively inhibit the scaling of the secondary ultrafiltration permeate formed in the process due to excessively high calcium ion concentration, the Ca 2+ <3000mg / L. This method is efficient, practical, economical, easy to operate, stable in operation and has strong adaptability.

The invention discloses a calcium ion content dynamic detection method based on a desulfurization gypsum dissolution experiment. The method comprises the following steps: establishing a standard working curve of calcium ion concentration and absorbance value in advance; building an online detection system consisting of a reaction container, a microporous filter head, a precise peristaltic pump, a dynamic mixer and a flow-type detection pool; the method comprises the following steps: continuously pumping out clear liquid in a reaction container by using a precision peristaltic pump in a desulfurization gypsum dissolving process, mixing the clear liquid with a mixed color developing reagent on line, and enabling the mixed liquid to flow into a flow-type detection pool of an ultraviolet and visible spectrophotometer for real-time dual-wavelength absorbance detection; and finally, converting the absorbance value subjected to background correction into calcium ion concentration through a standard working curve, and drawing a dissolution kinetics curve. According to the method, in-situ, continuous and high-precision monitoring of the calcium ion concentration in the desulfurization gypsum dissolving process is achieved, and the defects that a traditional interruption sampling method is tedious in operation, large in system disturbance and poor in anti-interference capacity are overcome.

The present invention aims to provide a method for measuring endotoxin concentration of dialysate with higher accuracy using a calibration curve made of water, and a kit for the method. The present invention provides a method for measuring endotoxin as follows: mixing a prescribed amount of a test sample with a dry powder containing a solubilizer reagent to prepare a first reaction solution, then incubating the first reaction solution for a prescribed time, mixing the first reaction solution with a dry powder containing a luciferase bioluminescence reagent under light shielding to prepare a second reaction solution, measuring the amount of luminescence of the second reaction solution, and measuring the endotoxin concentration of the test sample, which is dialysate or water, from the amount of luminescence, the second reaction solution having a sodium ion concentration of 250 to 390 mM, a calcium ion concentration of 0.5 to 10 mM, a chloride ion concentration of 250 to 361.5 mM, and a Tris concentration of 20 to 30 mM.

The invention provides a preparation method of a porcine epidemic diarrhea virus and application of the porcine epidemic diarrhea virus in improving the titer and N protein expression of the porcine epidemic diarrhea virus, and relates to the technical field of biology. The preparation method of the porcine epidemic diarrhea virus provided by the invention comprises the following steps: inoculating host cells with the porcine epidemic diarrhea virus, adding calcium salt in the virus culture process to regulate the concentration of calcium ions in a culture medium to 0.6-5.1 mmol / L, and continuously culturing to obtain the porcine epidemic diarrhea virus. The preparation method is simple in process, and the cultured porcine epidemic diarrhea virus is high in titer and high in N protein expression quantity.

The invention discloses a resveratrol-based micromolecular scale inhibitor as well as preparation and application thereof, and belongs to the field of industrial and commercial circulating cooling water. The natural product-based micromolecule scale inhibitor is synthesized by taking resveratrol as a raw material. Static scale inhibition experiments and concentration ratio tests show that the scale inhibition performance of 0.01 wt% of the resveratrol-based small molecular scale inhibitor on calcium ions at 80 DEG C is better than that of sodium polyacrylate and EDTA-2Na with the same mass concentration, the calcium ion concentration of supernatant liquid after addition is 151.66 mg / L, and the resveratrol-based small molecular scale inhibitor is still clear after concentration. The resveratrol-based micromolecular scale inhibitor disclosed by the invention is efficient, green and environment-friendly, and a new scheme is provided for circulating water treatment.

The invention belongs to the technical field of efficacy evaluation of oral care products, and discloses a test method for in-vitro evaluation of anti-acid calcium locking effects of oral care products, which comprises the following specific steps: step 1, preparing an acidic solution, weighing a proper amount of phytic acid solution, adding into deionized water, adjusting the pH value to 4.5, fixing the volume to 1000mL, and shaking uniformly for later use; 2, sample configuration (pretreatment); the method comprises the following steps: by taking in-vitro bovine tooth enamel as a model, pretreating by using a sample, performing primary demineralization for 1 hour by using a phytic acid solution with the pH value of 4.5, measuring the calcium ion concentration of demineralization liquid, calculating the calcium locking multiple / proportion, and performing statistical test to judge whether the toothpaste has the acid-resisting and calcium-locking effects or not. According to the method, the experimental period is greatly shortened, only about 4 h is needed from sampling to quantitative result obtaining, and the time is shortened compared with that of a traditional pH circulation model; the cost is low, and expensive animal experiments or complex buffer systems are not needed; the method is good in reproducibility, adopts one-time phytic acid demineralization, is fixed in condition and high in stability, and reduces batch difference.

The application discloses a pectinase mutant and a production method and application thereof, and belongs to the technical field of bioengineering.The amino acid sequence of the pectinase mutant is that negative-charged aspartic acid at positions 162, 164 and 203 of a wild-type pectinase amino acid sequence is replaced by neutral asparagine; the amino acid sequence is shown as SEQ ID NO:2; and the pectinase mutant can be obtained by constructing a recombinant vector containing a coding gene of the pectinase mutant and expressing the pectinase mutant by a recombinant cell.The pectinase mutant provided by the application can reach more than 80% of the enzyme activity under a conventional calcium ion (1-2 mM) concentration (determined at 50 DEG C) without adding calcium ions, which is significantly higher than that of a wild-type pectinase which is almost completely inactivated under the same treatment condition.The pectinase mutant provided by the application can be widely applied to the elimination of anti-nutritional factors in feed processing and cotton and hemp degumming and refining in the textile industry, and has a good application prospect.

This invention discloses a rapid method for detecting calcium signals in undifferentiated and differentiated spermatogonia. The method uses a mild enzymatic digestion method to prepare a testicular single-cell suspension. Indo-1 AM, Thy-APC, and c-kit-PE are used for staining and labeling. The cell population to be analyzed is determined based on the difference between the lateral and forward scattering areas of the cells in the testicular cell sample. Then, Thy-APC and c-kit-PE are used to label undifferentiated and differentiated spermatogonia, respectively, to further select specific cell groups. Finally, the fluorescence intensity changes of indo-1 AM in each specific cell subpopulation are detected, thereby obtaining the changes in calcium ion concentration in undifferentiated, undifferentiated-to-differentiated, and differentiated spermatogonia. This method can rapidly analyze the calcium ion concentration in undifferentiated, undifferentiated-to-differentiated, and differentiated spermatogonia. The method is simple and convenient, and provides a foundation for identifying spermatogonial dysfunction caused by calcium signal imbalance.

The invention discloses a pectinase mutant as well as a production method and application thereof, and belongs to the technical field of bioengineering. The amino acid sequence of the pectinase mutant is characterized in that aspartic acid with negative charges at the 162nd site, the 164th site and the 203th site of the amino acid sequence of wild pectinase is replaced with neutral asparagine; the amino acid sequence is shown as SEQ ID NO: 2; the gene can be obtained by constructing a recombinant vector containing the coding gene and performing recombinant cell expression. Under the condition that calcium ions are not added, the enzyme activity of the pectinase mutant provided by the invention can reach more than 80% (measured at 50 DEG C) of the enzyme activity under the conventional calcium ion (1-2mM) concentration, and is obviously higher than that of wild type pectinase which is almost completely inactivated under the same treatment condition. The pectinase mutant provided by the invention can be widely applied to elimination of anti-nutritional factors in feed processing and degumming and refining of cotton and linen in textile industry, and has a good application prospect.

The invention discloses a microfluidic device based on an MMPs-DNAzyme-PMPs compound and a detection method, and belongs to the technical field of biological detection. According to the invention, DNAzyme molecules are combined with magnetic particles (MMPs) and polystyrene particles (PMPs), and the obtained composite structure (MMPs-DNAzyme-PMPs) can trigger a DNAzyme cutting reaction in the presence of calcium ions, so that free PMPs are released. In combination with an automatic capillary tube driving micro-fluidic device, the PMPs are captured and accumulated by utilizing the characteristic that the aperture of the tail end of a particle dam is smaller than the diameter of the free PMPs, a visual length strip is formed, and rapid quantitative detection of the blood calcium ion concentration can be realized through naked eyes or a mobile phone camera. The enrichment and concentration visualization of the calcium ions can be realized only by using a trace amount of blood sample, and the method is suitable for instant detection of families and medical sites.