Bicuculline and picrotoxin block γ-aminobutryic acid-gated Cl− conductance by different mechanisms

Summary Using isolated, internally perfused bullfrog dorsal root ganglion cells we have studied the dose-response curves for -aminobutyric acid (GABA) in the presence of internally or externally applied GABA antagonists. With external application of antagonists the inhibition of the GABA current by bicuculline was competitive and that by picrotoxin was noncompetitive. Picrotoxin but not bicuculline blocked when internally perfused.To whom reprint requests should be addressed.Acknowledgments. We thank Drs S. Minakami and S. Yasui for helpful discussions and comments.     

金华地区虎纹蛙消化道形态解剖学观察

对金华地区虎纹蛙消化道各部进行了形态解剖学观察.结果表明:虎纹蛙消化道较为明显地分为口咽腔、食道、胃、十二指肠、空肠、回肠、直肠和泄殖腔.同时,对其主要的消化腺肝脏和胰脏进行了观察与测量.观察分析表明虎纹蛙消化道的结构与其食性是相适应的.     

一类非线性Sine－Gordon方程的一个“蛙跳”有限差分格式

本文给出了一类非线性Ｓｉｎｅ－Ｇｏｒｄｏｎ方程的一个“蛙跳”有限差分格式．讨论了三对角循环线性系统的微分方程的可能性，进一步的，利用能量不等式的方法研究了差分格式的收敛性和稳定性，最后，给了一个数值解的例子     

Substance P-like immunoreactivity in the frog dorsal root ganglia

Summary The distribution of substance P-like immunoreactivity was studied in the thoracic dorsal root ganglia of the frogRana esculenta by immunohistochemistry. Substance P-like immunoreactivity was contained in approximately 50% of primary sensory neurons. The immunoreactive fibers arising from the cell bodies are collected in small bundles within the ganglia neuropil before entering the central and peripheral roots.     

中国蛙类原虫与棘头虫名录

为了解我国蛙类原虫与棘头虫的种类与地理分布,收集了报道我国蛙类原虫与棘头虫的相关文献,依据较新的原虫与棘头虫分类系统整理成名录.共记录在中国31种蛙体内检出原虫61种,隶属于7门、11纲、12目、14科、23属;棘头虫8种,隶属于1门、2纲、2目、2科、3属.列出了每种原虫和棘头虫的中文名称、拉丁文名称、命名人与命名年、宿主与寄生部位、地理分布及文献来源等信息,为较全面了解我国蛙类原虫与棘头虫的种类情况提供了基础材料.     

东北地区发展林蛙养殖业的探讨

本文介绍了东北地区林蛙的生活习性，养殖方式和方法。对保护林蛙资源，提高蛙农业效益，促进本地经济进行了探讨。     

Freeze tolerance in the frog,Rana sylvatica

Summary Wood frogs survive extracellular freezing at moderate subzero temperatures (–4°C) for at least 11 days. Freezing survival is aided by the accumulation of high concentrations of glucose as a cryoprotectant in blood and tissues. Glucose production was accompanied by a rapid decline in liver, but not muscle, glycogen levels suggesting that liver is the organ controlling cryoprotectant synthesis.Acknowledgments. This study was supported by grants to L.M.G. from the Kroc Foundation (Santa Ynez, California) and from the National Institute of Dental Research (Grant No. DE-03987). The authors wish to thank K. Yorko, M. Shakin, J. Finan and Mrs N. Manivannan for their technical and secretarial assistance.Acknowledgments. I thank Dr J. Ballantyne, Dr F. Schueler and I. McMurray for help with frog collections and Dr. W. Schmid, Dr J. Bogart and Dr F. Cook for helpful discussions. Supported by an N.S.E.R.C. operating grant and by a grant from the Atkinson Charitable Foundation.