Objective To select a best mouse strain for establishing an animal model of orthotopic transplanted liver cancer through comparison analysis.Methods C57,C3H and BALB/c mice( each 10) were selected as model groupⅠ,Ⅱ and Ⅲ.H22 cells were inoculated into the liver parenchyma of mice in model group along the ventral midline laparotomy.Fifteenth days after injection of laparotomy,the rate of tumor was observed,the volume of ascites and gross tumor volume were measured,and tumor pathology was analyzed.Results The survival rate of mice in three groups was 100%. After 15 days,ascites in three groups were produced,but with no significant difference among the three groups of the volume of ascites.Tumor transplantation rate in model groupⅠwas 100%,which was higher than 60%in model groupⅡand 30%in model group Ⅲ.Liver tumors in model group Ⅰ were all large compact grayish white lesions, and the average tumor volume was significantly greater than that of model group Ⅱ and Ⅲ( P <0.05 ) .Pathology results confirmed that white lesions in liver of three groups were hepatocelluar carcinoma in situ.Conclusion C57 is the better ideal experimental animal for establishing orthotopic liver caner model,and these results will provide a good experimental platform for research in pathogenesis of hepatocellular carcinoma.

Objective To investigate if there are differences in hematological indexes between BALB/c mutant curly mice and normal BALB/c mice.Methods 6 week old BALB/c mutant curly and normal BALB/c mice of each 20 ( male and female) were selected, and 8 blood routine indexes and 15 serum electrolytes and biochemical indexes were detected using automatic blood cell analyzer and automatic biochemical detection, and the results of two groups were compared.Results The sex and group results of WBC,MCV,PLT and MCHC between BALB/c mutant curly mice and normal mice have significant differences ( P <0.05, P<0.01 );the sex and group results of Na+、K+and Cl-between BALB/c mutant curly mice and normal mice have significant differences( P<0.05,P<0.01);the sex and group results of ALT、GLU and TG between BALB/c mutant curly mice and normal mice have significant differences(P<0.05,P<0.01). Conclusion Some hematological indexes between BALB/c mutant curly and normal BALB/c mice are different clearly, and these results will provide the theoretical references for researching and using mutant curly mice model.

Objective:To explore the application and effect of the online teaching in the clinical nursing practice of obstetrics and gynecology during the coronavirus disease 2019 (COVID-19) epidemic.Methods:A total of 26 undergraduate nursing interns in the obstetrics and gynecology department of Xiangya Hospital of Central South University during the epidemic period were enrolled in this study. The interns accepted online practical teaching, and the teaching effect was analyzed and evaluated through the results of the exit examination and online teaching satisfaction.Results:The theoretical course scores of nursing students are all above 80 points, among which 22 (84.62%) are above 90 points. The operation scores are all above 90 (94.04±2.96) points. The results of the online teaching satisfaction survey show that, 23 (88.46%) nursing students are satisfied with the effect of their online practice.Conclusion:The online teaching mode during COVID-19 epidemic can help nursing students master the theoretical knowledge of obstetrics and gynecology, improve their clinical reasoning ability, strengthen their practical operation skills, and enhance their autonomous learning ability.

Objective To evaluate the efficacy,bleeding profile and safety of low-dose levonorgestrel-releasing intrauterine system (LNG-IUS 8) in Chinese healthy women of childbearing age.Methods A multi-center,open-label,single-arm clinical trial conducted at 16 centres in China enrolled 773 healthy women of childbearing age (mean age 31.6 years old,range 18 to 40 years old),who demanded contraception,from April 2006 to June 2013.All women placed LNG-IUS 8 for 3 years and then been followed up at 3,6,9,12,18,24,30,36 months.The efficacy variables including pregnancy rate and expulsion rate were analyzed using life table,while observing adverse events (AE) to evaluate the safety.The bleeding profile happened during the study was assessed using 90-day reference intervals (World Health Organization criteria).Results Eight pregnancies occurred among 773 women,resulting in a overall Pearl index of 0.42 per 100 women years.The 3-year cumulative pregnancy rate was 0.37 per 100 women years and the 3-year cumulative expulsion rate was 1.99 per 100 women years.The number of women with bleeding/spotting reduced and the bleeding/spotting days declined over time.Totally 219 AE were reported related to LNG-IUS 8 placements.The most common AE were vaginal bleeding (8.2％,63/773)and the ovarian cyst (6.2％,52/773).LNG-IUS 8 had an improving effect on dysmenorrhea that the percentage of women with dysmenorrhea as well as the days of dysmenorrhea decreased over time.The percentage of women satisfied or very satisfied with LNG-IUS 8 was 87.2％ (622/713).Conclusion LNG-IUS 8 is highly effective and safe for Chinese healthy women of childbearing age.

Objective To investigate the epidemiological characteristics of a family clustering of COVID-19. Methods Field epidemiological survey was conducted. Result Case 1 of the long-term residents from Hubei province was the source of infection of this family clustering. There were 6 cases (from case 2 to case 7) infected in the whole incubation period. The incubation period was more than 14 days for 3 of the second-generation cases. Routes of transmission include respiratory droplets (from case 1 transmitted to case 6, from case 1 to her family members) and closecontact (from case 1 to other cases in her family). All the age groups were generally susceptible, while elderly were easier to progress to critically ill. Besides respiratory symptoms, there were also gastrointestinal symptoms, of which diarrhea was the most common one. Conclusion Family clustering had been an important part for COVID-19 cases.