Induction and rapid repair of sister-chromatid exchanges in multiple murine tissues in vivo by diepoxybutane

Sister-chromatid exchange (SCE) induction by the direct-acting bifunctional carcinogen, diepoxybutane (DEB), was investigated in multiple tissues in vivo. The log-log dose SCE response relationship was found to be parallel to that previously reported for DEB induction of lung adenomas. However, the SCE assay is approximately 20 times as sensitive in detecting genotoxic effects of DEB than indicated by the lung adenoma assay. Examination of second and third division cells following various treatment protocols revealed that regardless of the nature of initially induced lesions, they are rapidly repaired with no evidence of persistence beyond 1 cell cycle.     

中国拟盘多毛孢属真菌的七个新组合

作者按照Steyaert(1949)和Sutton(1980)的分类观点,对1987—1988年从我国广西、江西、浙江等地采集的Pestalotiopsis属真菌进行了研究,确认了拟盘多毛孢属真菌的7个新组合种,即Pestalotiopsis carveri(Guba)comb nov.,Pestalotiopsis elasticae(Koord.)comb.nov.,Pestalotiopsis langloisii(Guba)comb.nov.,Pestalotiopsis oleandri(Guba)comb.nov.,Pestalotiopsis sinensis(shen)comb.nov.,Pestalotiopsis sydowiana(Bres.)comb.nov.和Pestalotiopsis zahlbruckneriana(Bres.)comb.nov.     

四川王朗自然保护区大熊猫主食竹——缺苞箭竹(Fargesia denudat)不同发育时期酯酶和α-淀粉酶同工酶的研究

通过聚丙烯酰胺凝胶电泳,对生长在亚高山地带的大熊猫主食竹的实生苗、成竹和开花竹中不同发生年龄鞭系,以及同一鞭系内一系列生长年龄竹株作了酯酶、α-淀粉酶同工酶的比较研究。结果表明,同一竹种的不同发生年龄鞭系之间叶酯酶电泳类型存在明显差异,而同一鞭系内α-淀粉酶同工酶的变化表现与竹株生长年龄有关。由此认为,上述同工酶系统可以用作竹类无性系发育分析的生理指标。     

Perinatal transmission of HIV-I in Zambia.

OBJECTIVE--To determine the occurrence of vertical transmission of HIV-I from women positive for the virus and the prognosis for their babies. DESIGN--Women presenting in labour were tested for HIV-I. Their newborn babies were also tested. Women positive for the virus were followed up with their babies for two years. SETTING--Teaching hospital in Lusaka, Zambia. SUBJECTS--1954 Women, of whom 227 were seropositive. Of 205 babies, 192 were positive for HIV-I. After birth 109 seropositive mothers and their babies and 40 seronegative mothers and their babies were available for follow up. MAIN OUTCOME MEASURES--Serological examination of mothers and their babies by western blotting. Birth weight and subsequent survival of babies. Women and babies were tested over two years for signs of seroconversion and symptoms of infection with HIV, AIDS related complex, and AIDS. RESULTS--Of the 109 babies born to seropositive mothers and available for follow up, 18 died before 8 months, 14 with clinical AIDS. Of the 91 remaining, 23 were seropositive at 8 months. By 24 months 23 of 86 surviving babies were seropositive, and a further five infected babies had died, four were terminally ill, 17 had AIDS related complex, and two had no symptoms. The overall rate of perinatal transmission was 42 out of 109 (39%). The overall mortality of infected children at 2 years was 19 out of 42 (44%). Before the age of 1 year infected children had pneumonia and recurrent coughs, thereafter symptoms included failure to thrive, recurrent diarrhoea and fever, pneumonia, candidiasis, and lymphodenopathy. All babies had received live attenuated vaccines before 8 months with no adverse affects. CONCLUSIONS--Vertical transmission from infected mothers to their babies is high in Zambia and prognosis is poor for the babies. Perinatal transmission and paediatric AIDS must be reduced, possibly by screening young women and counselling those positive for HIV-I against future pregnancy.     

Virological survey of rhesus monkeys in China

A virological survey of rhesus monkeys captured in China for 13 viruses and/or antibodies was performed. Antigens used were SFV, SF40, HSV-1, Sa11, measles, vaccinia, epidemic or simian hemorrhagic fever, Langat, Kunming, poliomyelitis, HIV, SV41 and rubella. Monkeys were from Sichuan, Hunan, Guizhou, Yunnan and Guangxi provinces. Antibody was detected to all the listed viruses except HIV, SV41 and rubella. Both SFV and SV40 were recovered from monkeys, but H. simiae, LCM and coxsackieviruses were not.     

钼,铁,硫化合物激活曝氧的棕色固氮菌固氮酶钼铁蛋白的研究

曝氧后,棕色固氮菌(Azotobacter vinelandii)固氮酶钼铁蛋白的催化活性和圆二色信号都显著降低,而吸收光谱则显著增加。与钼、铁、硫化合物和二硫苏糖醇组成的重组溶液保温后,曝氢蛋白的圆二色信号和吸收光谱几乎完全恢复至天然状态的同时,乙炔还原活性也得到了显著的恢复,表明重组溶液可使曝氧蛋白中的 P-cluster和其它活性部位都得到了不同程度的修复。