Objective To explore the causes of per-hospitalization high inpatient expenditure of a tertiary hospital in 2015,by analyzing the influencing factors.Methods We retrospectively studied 1 282 inpatient cases who cost more than 100 000 yuan per case at a tertiary hospital in 2015,analyzing statistically major influencing factors of such expenditure in variance analysis and multiple stepwise regression analysis.Results The average days of stay of these cases were 27.6 days,and the average medical cost of those cases was 149 153 yuan per person.Costs for medicines and material made up a large proportion of medical costs,respectively accounting for 33.38% and 31.98% of the total.The days of stay,prognosis of the patient,complications as well as hospital infection,surgeries,gender of the patients constituted major factors on inpatient medical expenditure.Conclusions Reducing the average days of stay,guiding reasonable applications of drugs and medical materials,strengthening management on operations and controlling excessive medical services are effective approaches to reducing excessive growth of medical costs.

Purpose/Significance By investigating and analyzing the characteristics of scientific data citation of scientific data sharing institutions in the field of medical and population health,the paper provides references and guidance for open sharing and standardized ci-tation of scientific data.Method/Process Taking the National Population Health Data Center as an example,the literature analysis meth-od is used to analyze the scientific data citation behavior and its traceability in this field.Result/Conclusion It is found that there are non-standard citation behaviors such as inconsistent labeling positions and missing citation elements in the scientific data in the field of medical and population health,and a large number of open and shared scientific data cannot be effectively traced.It is urgent to improve the standards of scientific data citation,strengthen the management of scientific data platform,enhance the awareness of scientific re-searchers,and promote scientific data sharing and citation.

Purpose/Significance To analyze the management problems of scientific data collection in the biomedical field and put forward countermeasures in order to improve the dissemination of scientific data.Method/Process Based on the relevant national scientif-ic data collection policy,taking the National Population Health Data Center as an example,the challenges and countermeasures of scien-tific data collection in the biomedical field are analyzed from the perspective of scientific data manager.Result/Conclusion The paper puts forward some countermeasures to solve the problems,including popularizing the scientific data collection mechanism,setting stand-ards and conducting audits of biomedical science data quality and standardization,strengthening data security and privacy protection tech-nology research and development in accordance with relevant laws and regulations.

OBJECTIVE： To study the in vitro inhibitory effects and antioxidant activity of different solvent extracts of Boehmeria nivea leaves against influenza A virus（H1N1）， and to expand the medicinal parts of B. nivea and develop natural antiviral and antioxidant drugs. METHODS： The leaves of B. nivea were extracted with 95％ ethanol. The ethanol extract was dissolved by water heating， and extracted with different solvents to obtain petroleum ether phase， trichloromethane phase， ethyl acetate phase， n-butanol phase and aqueous phase extracts of B. nivea leaves. The toxicity of aqueous extract of B. nivea leaves （50-400 μg/mL） on Madin-Darby canine kidney （MDCK） cell line was investigated. Using ribavirin as positive control， MDCK cells were attacked by influenza A virus（H1N1）. Western blotting assay was used to detect the expression of nucleoproteins （NP） in viral infected cells after treated with same concentrations of petroleum ether phase， trichloromethane phase， ethyl acetate phase， n-butanol phase and aqueous phase extracts of B. nivea leaves （100 μg/mL）， different concentrations of aqueous phase extract solution of B. nivea leaves （50， 100， 200， 400 μg/mL） and different concentrations of ribavirin solution （0.31， 0.63， 1.25 μg/mL）. Using vitamin C as a positive control， hydroxyl radical（·OH） scavenging test， DPPH radical scavenging test and reduction test were used to investigate in vitro antioxidant activity of the extracts. RESULTS： Aqueous phase extract of B. nivea leaves with concentration less than 400 μg/mL was nontoxic to MDCK cells. The petroleum ether phase， trichloromethane phase， ethyl acetate phase and aqueous phase extracts at 100 g/mL could significantly reduce the expression of NP protein in influenza A virus（H1N1） infected cells （P＜0.01）. Different concentrations （50-400 μg/mL） of aqueous extract could significantly reduce the protein expression of NP （P＜0.01） in concentration-dependent manner. The in vitro antioxidant activity of petroleum ether phase and ethyl acetate phase was similar to that of vitamin C. CONCLUSIONS： B. nivea leaves extract have better anti-influenza A virus（H1N1） effects in vitro， and the extracts of petroleum ether phase and ethyl acetate phase show good antioxidant activity in vitro.