This paper firstly analyses the sales and purchase contracts in the procurement of drugs in public hospitals, and then points out the market failure in the two contracts. After the implementation of administrative measures such as government pricing, administrative price reduction, price increase, centralized bidding and purcha-sing, various drug procurement stakeholders have adopted various game behaviors, and government procurement and price formation have appeared in government hospitals, not-neglecting the formation of the price ofGovernment fail-ure. The future price formation in public hospitals should be the market pricing under the limited government regu-lation, and increase the medical insurance institutions' price negotiation and the public hospitals' participation degree in the bidding process based on maintaining the centralized bidding and purchasing and zero administrative rate.

In this study, a novel polyurethane membrane, modified by superfine silk-fibroin powder, was prepared for small-diameter vascular grafting. Scanning electron microscopy, transmission electron microscopy, and histological examination were applied to evaluate histocompatibility of this polyurethane membrane. The polyurethane membrane was compared with polytetrafluoroethylene material. A pseudomembrane and gap formed between polytetrafluoroethylene and the surrounding tissues, and no cells infiltrated or grew into the polytetrafluoroethylene material. On the contrary, superfine silk-fibroin powder/polyurethane blend membrane merged tightly with the surrounding tissues without gaps, and cells infiltrated and grew into the material. Moreover, the negative effects of superfine silk-fibroin powder/polyurethane blend membrane on cells were less than those of its polytetrafluoroethylene counterpart. Our findings indicated that the superfine silk-fibroin powder/polyurethane blend membrane has better histocompatibility than polytetrafluoroethylene membrane. It is concluded that the superfine silk-fibroin powder/polyurethane blend membrane is a promising biomaterial for small-diameter prosthesis.

Objective:To compare the wear resistance between dentin and dental restoration material in vitro.Methods:The friction and wear behaviors of natural tooth dentin respectively against highly polished polymer ceramic,glass ceramic and zirconia were investigated in an artificial saliva test environment by UMT-2 friction and wear testing machine.Worn surface morphology was observed by scanning electron microscopy(SEM),roughness was measured by roughness instrument,the rigidity value was weighed by electronic balance.Results:The roughness of the 3 materials was similar to that of dentin(P ＞ 0.05),the rigidity of dentin was less than that of the 3 materials (P ＜ 0.05).After friction and wear test,the abrasion quantity of dentin respectively against the 3 materials was less than that of the materials (P ＜ 0.05).There was positive correlation between the wear loss and the hardness of the 3 materials and dentin(r =0.846).The mass loss of the dentin against Poly Ceramic after grinding abrasion was the closest among the 3 materials.Conclusion:Different materials have varying degrees abrasion against dentine.The Polymer Ceramic has closer abrasion performancez with dentin than the other 2 materials.

Objective To compare the dissolution behavior between domestic trepibutone tablets and original reference product, and provide a basis for evaluating the quality consistency of generic drugs. Methods Four dissolution media recommended by Japanese Orange Book and a domestic standard dissolution media were selected to determined the dissolution profile,and f2 factor was calculated to investigate the consistency of stripping curves. Results In water,pH 4.0 and pH 1.2,the f2 of domestic formulation and reference formulation was under 50,and the dissolution profile was inconsistent.Dissolution behavior of domestic preparations of different manufacturers was dissimilar.In water,the f2 of domestic preparations of different batches of the same manufacturer was over 99.9,and the dissolution behavior was similar. Conclusion The dissolution method of existing domestic standard can not distinguish the dissolution behavior of different products,and it should be revised and completed.There is still great difference in quality between the domestic preparations and reference preparations.

The receptor of the heart transplantation was a patient with terminal dilated cardiomyopathy, the donor was a patient with congenital ventricular septal defect, in situ double-chamber heart transplantation was performed, and the result of the four-year follow-up was satisfactory. At present, donor is deficient,and those donors with congenital defect can also obtain satisfactory clinical application effects after appropriate handling.

Objective To study the effect of sub-chronic exposure to dehamethrin(DM) on the behavior of mice in learning and memory.Methods 60 Female SPF Kunming mice were randomly divided into 4 groups and given DM by gavaging for 60 days.Morris water maze (MWM) was used to evaluate spatial memory in mice.Results After exposure to DM,the escape latency of the solvent control group and the treatment groups were (12.20±6.5)s,(14.99±5.4) s,(15.64±8.3)s,(22.71±6.2)s on the fifth day.The escape latency of the high-dose group was higher than those of the low-dose group (P=0.0041) and the solvent control group (P=0.019) in the navigation test.The number of crossing position of the platform in the high-dose group ((2.93± 1.53)times) and the middle-dose group ((3.40± 1.12) times) were lower than that in the solvent control group ((5.87 ± 1.55) times) and the low-dose group ((4.90± 1.41)times)(P＜0.05).Conclusion Sub-chronic exposure to DM can damage the spatial learning and memory of mice.

BACKGROUND:Procolagen type 1 N-terminal propeptide (P1NP) and β-colagen special sequence(β-CrossLaps) are two bone metabolic markers that are closely related to osteoporosis. Combined detection of bone metabolic markers and bone mineral density is of clinical significance for the diagnosis of osteoporosis. Bone metabolic markers are ideal indicators to predict fractures, which can compensate for the lack of bone density test. OBJECTIVE:To introduce the application of bone metabolic markers in the monitoring of drug efficacy on the treatment of osteoporosis as wel as in the prediction of fracture risks in recent 20 years and to explore the clinical values of P1NP and β-CrossLaps to assess the therapeutic efficacy on osteoporosis and risks for osteoporotic fractures. METHODS:A computer-based search of CNKI and SCI databases were performed for relevant articles published from 2000 to 2014 using the keywords of “serum bone metabolic markers; osteoporosis; bone mineral density” in Chinese and English, respectively. Finaly, 44 articles meeting the inclusive criteria were reviewed. RESULTS AND CONCLUSION:This paper analyzes the source and detection mechanisms of P1NPand β-CrossLaps and then compares their advantages in the therapeutic effect assessment of osteoporosis. Serum bone metabolic markers cannot only reflect the dynamic changes of bone metabolism, but also have earlier changes than the bone mineral density. Both P1NPand β-CrossLaps are very important for assessing the early diagnosis of osteoporosis as wel as anti-osteoporosis drug efficacy.

Objective To study the effect of sub-chronic exposure to deltamethrin(DM) on the behavior of mice in learning and memory and expression of GABAA receptor α1 and γ2 subunits in the hippocampus of mice.Methods 60 female SPF Kunming mice were randomly divided into solvent control group,low-dose group,middle-dose group and high-dose group, 15 mice in each group.The latter three groups were exposured to deltamethrin for 60 days by gavage.Open field test (OFT) was applied to evaluate locomotor activity and exploratory behavior in mice.RQ-PCR was employed to measure the expression of GABAA receptor α1 and γ2 subunits in hippocampus of mice.Results After exposure to DM,the moving distance of the central area in the middle-dose group ((555.1 ± 12.8) cm) and high-dose group ((516.4± 11.88) cm) was significantly higher than that in the solvent control group ((327.3± 117.8) cm, P＜0.05).Numbers of standing in marginal area (F=4.117, P=0.010) and total movement distance (F=2.914, P=0.042) in the high-dose group ((27.9±9.9) times, (3211.3±379.8) cm) were also significantly higher than that in the solvent control group ((15.1 ±8.9)times, (3211.3±379.8)cm).The expression of GABAA receptor α1 subunit mRNA in the middle-dose group and high-dose group was significantly lower than that in the low-dose group and solvent control group(F=8.508, P=0.001) and the expression of GABAA receptor γ2 subunit mRNA in high-dose group was significantly lower than that in the other groups (F=6.738, P=0.002).Conclusion Sub-chronic exposure to DM can damage the function of locomotor activity and exploratory behavior,and inhibit the expression of GABAA receptor α1 and γ2 subunits in the hippocampus of mice.

Objective: To understand the changes of smoking behavior among primary and middle school students in Beijing during 2005-2015. Methods: The primary and middle schools in Beijing were classified and then taken as a sampling frame. Twophase stratified random cluster sampling was conducted with school as primary sampling unit (PSU) and class as the minimum sampling unit, respectively. Beijing Schoolbased Smoking Monitoring Questionnaire was surveyed in 2005 and 2005, 2010, 2011, 2013 and 2015 anonymously. Results: In 2015, the smoking rate among primary and middle school students in Beijing was 9.41%. Among them, for primary, junior, high school and vocational high school students, the rates were 7.05%, 7.06%, 12.41% and 34.11%, respectively. The smoking rates were now 3.26%, with 1.99%, 1.80%, 3.48% and 20.22%, respectively, among primary, middle and high school and vocational high school students. male, vocational school students were more likely to report smoking across six waves of surveillance. Results from the surveillance in 2015 showed a decreasing trend in ever smoking rate and current smoking rate compared with previous survey. About half of the current student smokers were reported to take 1 cigarette/day, and about 10% smokers were reported to take 10 cigarettes/day. Students were most likely to smoke at home(24.02%), followed by smoking at schools(12.74%). The percentage of buying cigarettes by themselves was increased from 17.10% in 2008 to 66.09% in 2015. Conclusion From 2005 to 2015, both ever smoking and current smoking rate among middle school students in Beijing decreased in general, however smoking among vocational high school students warrants further attention.

ibility than polytetrafluoroethylene mem-brane. It is concluded that the superfine silk-fibroin powder/polyurethane blend membrane is a prom-ising biomaterial for small-diameter prosthesis.