巯基物质在消炎痛诱发大鼠胃粘膜损伤中的作用

本工作研究了巯基物质在消炎痛引起大鼠胃粘膜损伤中的可能作用。在胃粘膜损伤发生过程中、胃粘膜内非蛋白及蛋白结合的巯基物质含量均无明显降低。虽然半胱胺灌胃(132或264μmol)或皮下注射(132μmol)后均明显抑制消炎痛溃疡的发生,其抑制率分别为82％,92％和75％,但同样具有巯基的半胱氨酸却无保护作用。半胱胺(132μmol)皮下注射可使消炎痛大鼠胃酸分泌抑制46％,而灌胃则无此作用。两种途径给予的半胱胺均不影响胃壁结合粘液的分泌。这些结果表明,胃粘膜内巯基物质似不参与消炎痛的致溃疡过程。半胱胺在此种模型上虽有强烈的细胞保护作用,但似乎不是由于其分子上所带的巯基所致。因此,巯基物质在消炎痛引起的胃粘膜损伤模型上没有细胞保护作用。     

鳋科（寄生桡足类）胸板的扫描电镜比较研究

本文利用扫描电镜观察了我国鳋科的5个属的种类。首次发现在它们的胸部腹面游泳足连接板之下均有一板状结构,其形状与栉齿的着生情况在不同属之间存在着明显的差异,同属不同种之间也不尽相同,这是一个过去未曾被注意过的结构,权且称之为胸板。它是一个独立的结构,不与连接板相连。胸板上的栉齿从形态-功能-适应三位一体分析,它与附着寄主有夭,以免被水流冲走,与无栉齿的相比,应是一个进步性状。     

武陵山地区的淡水软体动物

1988—1989年在我国西南武陵山地区对乌江、清江、澧水及沅江四大水系进行了资源考察。共采集到标本53种,隶属2纲12科27属,其中腹足纲41种,瓣鳃纲12种,内有7个新种(另外发表)。淡水软体动物的区系组成以东洋界种类占优势,有29种,占总数的54.8％;种类组成以沅江水系最多,有44种,其中22种仅采于沅江。田螺属(Viviparus Montfort,1810)的种类首次在东洋界境内被发现。文章对淡水软体动物的资源作了评价,并对寄生虫媒介贝类进行了叙述。     

白鹇距长与年龄的关系

注意到白鹧雄鸟距长在一定时期内随年龄增长的事实,本文根据相邻2年同一月龄之间有12个月的间隔,距长数据除有较为集中外一定又有组间明显差别的特点,推测估计部分标本之年龄,加上确知年龄的部分标本,共测定89个个体120个距长样本数据,得到距长随年(月)龄增长的关系式:SL=am/1+bm,用此式可以实测距长初步估计野外采集到的白鹇个体的年龄     

中国特产雉类—褐马鸡,藏马鸡和蓝马鸡卵壳的电镜观察

迄今为止,在国内有关野生鸟类卵壳的超微结构报道尚少。我们对中国特产鸡类——三种马鸡卵壳的表皮、气孔、木栅层、锥体层、乳头结、壳膜和基帽进行了扫描巨镜观察,并对结果进行了比较、讨论。认为三种马鸡不同结构的形态,对研究它们的亲缘关系提供了新的价值。     

Production of ethylene by gravistimulation: a potential problem with the interpretation of data from some experimental techniques

Abstract. Gravistimulation was investigated as a potential and unwanted component in the interpretation of physiological investigations on plants. Using both seedlings and mature sunflower plants, two situations are described where gravistimulation contributes significantly to the outcome of an experiment not initially designed to include this parameter. The number of adventitious roots formed in derooted seedings decreased when the tops of the plants were allowed to bend over under their own weight, and the effect correlated positively with the rate of ethylene production by non-vertical stems. In droughted mature plants, and increase in leaf and stem ethylene caused by water stress was supplemented by additional ethylene produced in the lower halves of stems. Drought had caused these stem tissues to wilt, become gravistimulated, and thus produce more ethylene. Other situations in which gravistimulated ethylene production and its physiological consequences are likely to be complicating factors in experiments are discussed. It is concluded that procedures that unnecessarily place experimental material in non-vertical orientations should be avoided.     

Construction and packaging of pseudotype retrovirus containing human N—ras cDNA antisense sequence and its biological effects on human hepatoma cells

N-ras is one of the transforming genes in human hepatic cancer cells.It has been found that N-ras was overexpressed at the mRNA and protein level in hepatoma cells.In order to explore the biological roles of N-ras in human hepatic carcinogenesis and the potential application in control of cancer cell growth,a preudotype retrovirus containing antisense sequence of human N-ras was constructed and packaged.A recombinant retrovirus vector containing antisense or sense sequences of N-ras cDNA was constructed by pZIP-NeoSV(X)1.The pseudotype virus was packaged ang rescued by transfection and infection in PA317 and ψ 2 helper cells.It has been demonstrated that the pseudotype retrovirus containing antisense N-ras sequence did inhibit the growth of human PLC/PRF/5 hepatoma cells accompanied with inhibition of p21 expression,while the retrovirus containing sense sequence had none.The pseudotype virus had no effect on human diploid fibroblasts.     

腐霉属分类性状评价及其中国的种

本文对腐霉属Pythium Pringsheim的研究历史作了简单的回顾,对该属的分类性状和系统进行了论述和评价,最后对中国已发现的55种腐霉,以检索表的方式进行了分类、检索。     

Territory strategy of the migratory Brown Shrike Lanius cristatus

Brown Shrikes Lanius cristatus are both transients and winter residents in Taiwan. Large numbers of birds crowd into the available habitat during the transient period, and the cost of maintaining territories changes greatly, depending on the number of shrikes present. This study examined how wintering Brown Shrikes adapt to the changing level of competition in territory establishment. About 24% of autumn transients arrived before any wintering birds, while 73% of wintering birds arrived during autumn transient time. The frequency of aggression recorded was significantly related to the number of birds seen along the transect line that day. Among ringed birds that returned during transient time, 80% returned directly to their previous territories, but some waited for the departure of transient birds before establishing territories. Territory compression occurred at high population densities. Departure from and arrival at the study area were frequent during the winter, but no birds moved territories within the study area. On average, 25% of ringed wintering shrikes returned to the study site in the subsequent years, while no transients returned. This low site tenacity may be. in part, a result of a high persecution rate along the migration route.     

白细胞介素－2中枢镇痛作用途径的探讨

抗ＩＬ－２受体α亚基的单克隆抗体不能阻断ＩＬ－２的中枢镇痛作用,以及丧失与ＩＬ－２受体β亚基结合能力的ＩＬ－２突变体仍具有提高大鼠痛阈的能力,这表明ＩＬ－２的中枢镇痛作用并不是通过ＩＬ－２受体所介导,亦表示ＩＬ－２的免疫和镇痛作用是通过不同的受体途径实现的。加之内源性阿片肽与ＩＬ－２分子有着共同的抗原决定基和结构相似性,提示ＩＬ－２可以与阿片受体直接结合产生中枢镇痛效应。从放射免疫法测定的ＩＬ－２侧脑室注射后不同时间大鼠脑内不同核团的内源性阿片肽含量,推测ＩＬ－２的中枢镇痛作用可能还与弓状核、室旁核、蓝斑等核团的β－ＥＰ和ＬＥＫ有关。