口服庆大霉素也会产生“耳毒性”

一般认为，庆大霉素的毒性反应常见于注射给药，但近年发现，口服庆大霉素也会产生毒性。     

感觉神经性聋群体遗传学研究

采用遗传流行病学调查设计方法，对51758名人群进行调查，筛查出疑为遗传性感觉神经性聋220例，通过分离分析确定出遗传性聋170例，患病率为3.3‰，其中常染色体隐性（AR）聋占57.6%，常染色体显性（AD）聋40.6% ,性连锁隐性（XR）聋1.8%，在排除明显致聋原因的耳聋中77%为遗传因素所致，在此基础上计算出各遗传方式的基因型频率，基因频率和杂合频率，并对不同家系类型的发病风险系数进行了估计。     

EXPRESSION OF BAX AND BCL－2 IN MOUSE OFFSPRING BRAIN AFIER MATERNAL ORAL ADMINISTRATION OF MONOSODIUM GLUTAMATE

Objective:To analyze the excitotoxicity of monosodium glutamate(MSG)in the offspring crebral cortex and hippocampal subresions after maternal oral administration of MSG.Methods:Kunming mice were given per os MSG(4.0g/kg)at 17-21 days of pregnancy and their offspring behaviors were studied at 10,20,30days postnatally.By using inmunohistochemical means,the involvment of Bcl-2 and bax in the glutamate-induced cell death in cortical and hippocampal neurons were examined.Cell damage was assessed by direct cell counting.Results:administration of monosodium glutamate during the fetal period in mice resulted in a moderate increase in the expression of Bax in principal neurons in CA1,CA2,CA3,CA4 and in the cerebral cortex at postpartum 10,20,30 days in the offspring mice,whereas Bcl-2 protein expressions were reduced significantly in the same regions as compared with those of controls.Conclusion:These findings suggest that glutamate toxicity results in cellular death via an apoptotic mechanism in which the Bcl-2/Bax-alpha molecular complex may be involved.The glutamate-induced apoptosis appears to be related to the modulation of Bcl-2 family gene products such as Bcl-2 and Bax.     

基因库影响未来医学发展

据英国媒体报道，由英国医学研究委员会、韦尔科姆基金会和卫生部三家联合筹建、共耗资4500万英镑的英国国家基因库将于明年开始征集样本。这个基因库以英国居民为主要信息源，将收集50万志愿者的基因样品、生活方式、工作环境、饮食习惯和他们的病史。     

In vivo and in vitro Cytogenetic Effect of Supermethrin

INTRODUCTlONSupermethrin,asyntheticderivativeofnaturalpyrethIininsecticides,belongstothegroupofso-calledpyrethroids.SupermethrinisatypeIIpyrethroidofCzechos-lovakoriginandsimilarinstructuretocypermethrin.Chemicallyitis(RS)-alpha-cyano-3-phenoxybenzyl-(lRS(2,2-dichlorvinyl)-2,2-dimethylcyklopro-panecarboxylate(Fig.1).Thepyrethroidspossesmanydesirab1eprope1tiesincludinghightoxicitytotargetobjects,lowmammaliantoxicityandgoodbiodegradationactivityintheenvironment.Thereareanumberofreportsde…