The paper reports the evaluation of the feasibility of using internal standard method for the determination of nicotine recovery in microdialysis in vitro. This in vitro experiment included two conditions. Nicotine and codeine phosphate were dissolved in Ringer's solution. Nicotine, codeine phosphate and the mixture of them were perfused through the CMA30 linear probe separately to calculate the proportion of the recovery (or delivery) of nicotine to that of codeine phosphate. And then codeine was perfused through the probe which was immersed in nicotine solution with different concentrations to calculate the proportion, too. In another condition nicotine was dissolved in rat plasma. The rat plasma protein binding rate was determined by using retrodialysis and internal standard method in vitro. The results are as follows: the proportion of the recovery (or delivery) of nicotine to that of codeine phosphate was fairly stable. The delivery of codeine was independent of nicotine concentration in the external medium. Protein binding rate determined by retrodialysis was almost the same as that determined by internal standard method. It suggests that the internal standard method is an effective way in the determination of nicotine recovery and codeine phosphate can be used as the internal standard.

Exosomes are secreted by living cells,which have the lipid bilayer and a large number of inclusions.We have found that exosomes derived from tumor cells play a crucial role in the development of tumor.Tumor-derived exosomes not only act as the messenger between tumor cells,but also perform as a carrier that affects the normal cells far away.Moreover,it has been reported to play positive role in the proliferation,differentiation,metastasis and immune resistance of tumor cells.

Objective To detect the in-vitro microdialysis recovery of nicotine by decrement method(i.e.retrodialysis) and to investigate its influence factors,thus to supply experimental evidence for the in-vivo microdialysis of nicotine.Methods The in-vitro recovery of nicotine was detected by concentration difference method(increment method and decrement method).The stability of recovery was observed.The effects of the pretreatment with perfusate,and the flow rates and concentrations of the perfusate on nicotine recovery were studied.Results Filtering and stirring treatment increased the recovery,but the time of ultrasound degassing showed no effect on the recovery.The recovery detected by increment method was as the same as that detected by decrement method.Nicotine recovery was independent of nicotine concentration in the external medium,showing good stability.Conclusion It is necessary to filter and degas the perfusate before microdialysis.Retrodialysis can be used for the determination of in-vivo nicotine recovery.

[Summary] Glucose-dependent insulinotropic polypeptide ( GIP) is known to promote the release of insulin fromβcells, but this function suffers from a defect in obese patients. More and more evidences suggest that GIP is the bridge between a high-fat diet, obesity, insulin resistance, and type 2 diabetes. With the deepening of research in GIP in type 2 diabetes and obesity, GIP may provide new ideas for the treatment of type 2 diabetes and obesity.

[Objective]To investigate the effect of cryopreservation on the antigenicity of vascularized bone allotransplantation,and to observe the patency of the pedicle and the osteosis of bone allografts,in order to find out the dose of immunosuppressive agent.[Method]Forty-eight New Zealand rabbits were involved in the study.Of them 16 rabbits served as donors,and 32 hosts.Allotransplantation of cryopreserved radius diaphysis with the vascular pedicles were implanted to 8 rabbits and immunosuppressive agent(CsA 10 mg/kg/d) was administrated 4 weeks after transplantation(group A),similar cryopreserved grafts with the vascular pedicles were implanted to 8 rabbits and immunosuppressive agent(CsA 5mg/kg/d) was administrated 4 weeks after transplantation(group B),similar cryopreserved grafts with the vascular pedicles were implanted to 8 rabbits and immunosuppressive agent(CsA 2 mg/kg/d) was administrated 4 weeks after transplantation(group C),allotransplantation of cryopreserved radius diaphysis with a vascular pedicle was performed in 8 rabbits(group D),and 16 donors were group E.Immunological analysis was performed at 1 weeks.Radiography was taken for each graft at 2,4,8,12 weeks.And 12 weeks after operation,the patency of the pedicle was observed through ink infusing and histological studies were performed.[Result]There was no difference of IFN-? between group A and group B.However,the levels of IFN-? in groups A and B were lower than that in group C.[Conclusion]Cryopreservation could reduce the antigenicity of vascularized allotransplant graft.After transplantation,the reject response is decreased,patency and osteosis of bone allografts are better,and the dose of immunosuppressive agent are decreased.

Objective To discuss a method to show the structure of small mammary gland well by computed radiography(CR).Methods By analyzing 150 radiographs of mammary glands,the results showed that the mammary structure showed well whether or not was depended on the size of mammary gland.Using 24 steps aluminum ladder mimiced the small mammary gland and radiography was taken with various parameters and different imaging plate(IP) shading ways,then processed and printed,after that it was measured by density instrument.Results The display of grey scale of 24 steps aluminum ladder was improved if shading 10~15 mm margin of the IP by collimator or shading the central by a square cuprum plate with 22 mm length and 0.2 mm thickness.Radiography of small mammary gland by the same way was performed and the mammary structure was also showed well.Conclusion Shading the exposing areas properly by collimator or cuprum plate during CR can apparently improve the display of small mammary structure.

0.05). From clinical point of view,it is suggested that the weight can be advantageous to forecasting Cr of children.

By means of DEAE-sephadex A - 50 column chromatography, the venom of Agkistrodon acutus was separated into fifteen fractions. The fraction Ⅱ was rechro-matographed, on sephadex G - 50 column and a single peak was obtained. The polyacrylamide disc gel electrophoresis also showed a single band. The fraction Ⅱ had strong fibrinolytic activity on dog plasma fibrin plate and showed direct fibrinolytic effect on heated fibrin plate. In addition to fibrinolytic activity, the fraction Ⅱ had fibrinogenolytic activity, In vitro and at aconcentration less than 17. 8 mg?L-1,the potency of fibrinolysis was higher than that of fib-rinogenolysis. Local hemorrhage activity which is characteristic for crude venom of Agkistrodon a-cutus was not found when the fraction 1 was injected hyperdermically in rabbit. The ip LD50 value of the purified fraction Ⅱ was determined to be 11. 1 mg ? kg-1 in mice and there was no gross hemorrhage found in the dead animals.

Objective:To further optimize the nutritional support program for elderly neurocritical patients, analyze the changes and influencing factors of serum albumin levels in elderly neurocritical patients after surgery, and explore the impact on prognosis.Methods:A retrospective cohort study was conducted to investigate the medical records of neurosurgical intensive patients in Shanghai Tenth People's Hospital from May 2015 to September 2019. All the patients were treated for at least 5 days after operation. Patients with severe liver and kidney dysfunction, mental illness and incomplete medical records were not included in the study. Patients aged ≥65 years were included as the experimental group and patients aged <65 years served as the control group. Generalized estimating equation and other models were used to analyze the difference in the trend of albumin level and its influencing factors between the two groups. Automated machine learning was used to explore the influence of factors such as albumin level, nutrition mode, age, sex, diagnosis, preoperative consciousness level on the prognosis of patients.Results:A total of 284 patients were included in the study, including 85 in the experimental group and 199 in the control group. There were no significant differences in baseline data such as sex, age, and proportion of nutritional patterns between the two groups. Generalized estimating equation and generalized mixed additive equation showed that albumin level in both groups reached the minimum on the 3rd day after operation, and the average level in the experimental group was significantly lower than that in the control group ( P=0.03). Cerebral hemorrhage, emergency surgery, and low preoperative albumin were risk factors ( P<0.05); intravenous supplementation of human albumin might have an adverse effect on the experimental group ( P = 0.047). Machine learning models suggested that the higher the serum albumin level at discharge, the better the prognosis at 1 month after surgery. The area under ROC curve was 0.906, the specificity was 93.7%, and the sensitivity was 67.0%. Conclusions:The changes of albumin level in elderly patients with neurological critical illness after surgery are basically the same as those in young patients, with the lowest albumin level on the 3rd day after surgery, and the albumin levels even lower on the 3rd day after surgery in patients with cerebral hemorrhage, emergency surgery and preoperative low albumin. The higher the albumin level at discharge, the better the prognosis of patients may be.

Objective:To explore the effects of necroptosis specific inhibitor-1 (Nec-1) on brain injury in rats after cardiac arrest and its mechanism.Methods:A total of 24 Sprague-Dawley (SD) rats were divided into Sham group, model group and Nec-1 group ( n = 8 per group) according to random number table method. In the Sham group, only general surgical procedures were underdone without inducing cardiac arrest. In the model group, the rats were subjected to asphyxial cardiac arrest followed by cardiopulmonary resuscitation (CPR) at 6 minutes after cardiac arrest. In the Nec-1 group, Nec-1 of 1 mg/kg was administered after cardiac arrest, and CPR was performed at 6 minutes after cardiac arrest. At 72 hours after CPR, neurological deficit scores (NDS) were assessed, serum S100B levels were measured by enzyme linked immunosorbent assay (ELISA), receptor-interacting protein 3 (RIP3) expression in cerebral cortex and hippocampus was observed under immunofluorescence and positive rate was calculated, and the levels of RIP3 protein expression in brain were analyzed by Western blotting. Results:At 72 hours after CPR, the rats in the model group showed obvious necroptosis and injury in brain. Compared with the Sham group, the NDS scores in the model group were significantly decreased [57.0 (52.7, 60.0) vs. 80.0 (80.0, 80.0), P < 0.05], the serum S100B was significantly increased (ng/L: 44.9±4.5 vs. 18.6±1.5, P < 0.05), the percentages of RIP3 positive cells in cerebral cortex and hippocampus were significantly elevated [cerebral cortex: (31.7±4.8)% vs. (11.6±3.2)%, hippocampus: (28.4±0.8)% vs. (10.9±0.6)%, both P < 0.05], and the levels of RIP3 protein expression in brain were significantly increased [RIP3 protein (RIP3/GAPDH): 0.708 (0.642, 0.722) vs. 0.408 (0.253, 0.504), P < 0.05]. After Nec-1 intervention, necroptosis and injury in brain were obviously improved. Compared with the model group, the NDS scores at 72 hours after CPR in the Nec-1 group were significantly increased [70.5 (68.5, 71.7) vs. 57.0 (52.7, 60.0), P < 0.05), the serum S100B was significantly decreased (ng/L: 31.9±2.7 vs. 44.9±4.5, P < 0.05), the percentages of RIP3 positive cells in cerebral cortex and hippocampus were significantly lowered [cerebral cortex: (23.7±4.1)% vs. (31.7±4.8)%, hippocampus: (20.4±0.4)% vs. (28.4±0.8)%, both P < 0.05], and the levels of RIP3 protein expression in brain were significantly declined [RIP3 protein (RIP3/GAPDH): 0.437 (0.379, 0.507) vs. 0.708 (0.642, 0.722), P < 0.05]. Conclusion:Nec-1 attenuated necroptosis of brain cells by inhibiting the expression of RIP3 protein, so as to reduce brain injury after cardiac arrest in rats.