The proliferation of splenic lymphocytes, the humoral immune response to sheep red blood cells and the phagocytotic function of intraperitoneal macrophages of mice were all stimulated by ig the flesh of Meretrix meretrixL. (FM) 20 g/kg and 10 g/kg for 7 days. FM 20 g/kg and 10 g/kg ig for 15 days also enhanced the activity of serum T-SOD, and decreased the level of serum MDA in old mice. The anti -stress effect of FM, such as increasing the swimming time of mice in 20癈 water by ig FM 20 g/kg and 10 g/kg for 7 days, was also achieved.

Objective To analyze the implementation of intervention programs targeted on AIDS high risk sexual transmission groups since 2008,when the relative prevention and control information systems on HIV/AIDS were developed.Methods Data from both aggregated interventions and sentinel surveillance programs from 2008 to the end of 2014 were used.Descriptive statistics were performed to analyze the trends of implementation on high risk groups including men who have sex with men,female sex workers (FSW) and migrant workers.Results From 2008 to 2012,the monthly average numbers receiving intervention programs and the average monthly coverage rate on intervention for MSM,increased from 49000 to 252000,and from 8.6％ to 78.5％ respectively.The FSW related indicators increased from 329 000 to 625 000,and from 30.9％ to 87.0％ respectively.Above indexes on the two populations had dropped slightly in 2013 and 2014.Sentinel surveillance data showed that knowledge and behavior indicators observed from the MSM and FSW populations increased annually.The coverage of intervention programs on migrant workers increased from 4.7％ to almost 10.0％,but the surveillance data on migrant men showed that the knowledge and behavior indicators were still lower than the other high-risk groups.Conclusion Intervention related to sexual transmission on HIV/AIDS among high-risk populations were effectively implemented,with some achievements seen.However,as sexual contact currently became the main route of AIDS epidemic,new challenges called for serious attention.

Objective To study the difference of clinical outcome between late preterm twins (LPT) and late preterm singletons (LPS),and the influence of assisted reproduction technology (ART) or natural conception on the clinical outcomes of LPT.Method The data of late preterm infants born in the Beijing Obstetrics and Gynecology Hospital between January 2016 and January 2018 were retrospectively collected.Infants were assigned to LPT group or LPS group according to twins or singleton status.The differences of the demographic data,morbidity,oxygen therapy rate,respiratory support rate,mortality,hospitalization rate and hospitalization time between LPT and LPS were compared.In order to analyze the effects of different ways of conception on LPT,LPT was further divided into assisted reproduction technology (ART) subgroup and natural pregnancy subgroup.Result A total of 1 824 late preterm infants were included in the study,including 582 cases of LPT and 1 242 cases of LPS.The birth weight and body length of LPT were lower than those ofLPS [(2572±395)gvs.(2614±413)g,P＜0.05;(46.5±1.1)cm vs.(47.5 ± 1.0)cm,P ＜0.01],while the cesarean delivery rate of LPT was higher than that of LPS [90.7％ (528/582) vs.39.9％ (496/1 242),P ＜ 0.01].The incidence of respiratory distress syndrome (RDS) in LPT was higher than that of LPS [5.2％ (30/582) vs.3.6％ (45/1 242),P ＜ 0.05],and the length of hospitalization of LPT was also longer than that of LPS[(8.9 ±3.1)d vs.(7.2 ±2.9)d,P ＜0.01],the differences were statistically significant.There were no significant differences between groups in neonatal pneumonia,apnea,hypoglycemia,sepsis,neonatal necrotizing enterocolitis (NEC),grade Ⅲ ～ Ⅳ intracranial hemorrhage,severe asphyxia,bronchopulmonary dysplasia (BPD),oxygen therapy rate,respiratory support rate and mortality rate.There was also no significant difference between ART subgroup and natural pregnancy subgroup in gestational age,gender,cesarean section rate,birth weight,and birth length (P ＞ 0.05).There was no significant difference in RDS,pneumonia,apnea,hypoglycemia,sepsis,NEC,Ⅲ ～ Ⅳ intracranial hemorrhage,severe asphyxia,BPD,oxygen uptake rate,respiratory support rate,mortality rate and hospitalization time between the two subgroups (P ＞ 0.05).Conclusion The birth weight and birth length of LPT are lower than those of LPS,and the incidence of RDS is higher.The hospitalization time of LPT is also longer than that of LPS.It is necessary to strengthen the high-risk management of twin pregnant women and post-natal management of LPT.

Objective:To evaluate the residual risk (RR) of transfusion transmitted HIV (TT-HIV) after the implementation of nucleic acid amplification test (NAT) in blood screening test among blood centers in China.Methods:The data of blood donors and HIV infection markers from 2017 to 2020 were collected from 28 blood centers via the Platform of Comparison of blood establishments Practice in Chinese Mainland. The new infection rate/window period mathematical model was used for two types of blood screening strategies, namely, two rounds ELISA plus individual NAT take turn with pooling NAT (2ELISA+ ID-NAT/MP-NAT) and two ELISA plus one round pooling NAT (2ELISA+ MP-NAT), and the RR of HIV infection was estimated also based on first donors (FDs) and repeated donors (RDs) in different blood donation years. T-test analyses were conducted for comparing TT HIV RR among FDs and RDs in different blood donation years with two blood screening strategies, and the variation trend of RR in HIV test was observed.Results:From 2017 to 2020, the RR of FDs in 2ELISA+ ID-NAT/MP-NAT blood screening strategy was 2.869/10 6 person-year, 3.795/10 6 persons-year, 3.879/10 6 person-year, and 2.890/10 6 person-year respectively. The RR of RDs was 1.797/10 6 person-year, 1.502/10 6 person-year, 1.857/10 6 person-year, and 1.483/10 6 person-year respectively. Significant difference exists between RR of FDs and RDs, with F=9.898 and p<0.05. In 2ELISA+ MP-NAT strategy, the RR of FDs was 3.508/10 6 person-year, 1.868/10 6 person-year, 2.204/10 6 person-year, and 1.765/10 6 person-year respectively. The RR of RDs was 0.948/10 6 person-year, 0.926/10 6 person-year, 0.748/10 6 person-year, and 0.682/10 6 person-year respectively. Statistical difference existed between RR of FDs and RDs, with F=17.126 and P<0.05. There was no significant difference between the RR of FDs in these two strategies with F=3.493 and P>0.05, while there was a difference between the RR of RDs in these two strategies with F=24.516 and P<0.05, and a difference between the RR of total donors (TDs) in these two strategies F=20.216 and P<0.05. Conclusions:The RR of TT HIV significantly decreased after the introduction of NAT into blood test among blood centers in China. There were some differences in the RR of HIV testing among different blood screening strategies. There could be significant differences in the RR of HIV testing among different groups of blood donors. Compared with FDs, RDs is the low risk group for HIV.