用PO4细胞为靶细胞检测人血清中Epstein-Barr病毒IgA/MA抗体以诊断鼻咽癌

近年来,常用未经丙酮固定的、由丁酸和巴豆油激活的B95-8细胞或P3HR-1细胞为靶细胞,检测人血清中EB病毒IgA/MA抗体以早期诊断鼻咽癌,效果良好。但由于B95-8细胞含有多种EB病毒抗原,不能用丙酮固定,需多次离心沉淀,在浮悬状态下检测,技术比较复杂。     

The involvement of cytochromeP-450 monooxygenase system in aflatoxin biosynthesis byAspergillus flavus

Summary Phenobarbital stimulated aflatoxin biosynthesis byAspergillus flavus and this was paralleled by an increase in microsomal NADPH-cytochromeP-450 reductase and cytochromeP-450 activities. Aflatoxin biosynthesis was inhibited by SKF 525-A, metyrapone and cyanide, inhibitors of the cytochromeP-450 monooxygenase system, further suggesting that aflatoxin biosynthesis byA. flavus could be mediated by a cytochromeP-450 monooxygenase enzyme system.     

光对尾穗苋幼苗内苋红素合成的诱导

不同苗龄的尾穗苋黄化苗对10 min,15Wm~(-2)白光的反应能力不同。光诱导的苋红素合成始于播种后第 20h,至50h合成能力最大,82h以后幼苗对短时光照的反应能力趋于消失。苋红素合成的滞后期为3h,光处理后18h色素积累达到高峰。光调节苋红素合成符合红光—远红光可逆诱导反应等两个基本模式,确证光敏色素参与调控苋红素合成.     

云南10个民族红细胞酸性磷酸酶型分布调查

用淀粉凝胶电泳法对云南省汉族及9个少数民族的红细胞酸性磷酸酶(ACP_1)的表型分布进行了调查,检出A、BA和B3种表型,计算得云南汉、彝、白、傣、瑶、佤、哈尼、布朗、基诺和拉祜族ACP_1~A、ACP_1~B的基因频率依次为0.2067、0.7933;0.2406、0.7594;0.2341、0.7659;0.3750、0.6250;0.2300、0.7700;0.2727、0.7273;0.3594、0.6406;0.3036、0.6964;0.2381、0.76119和0.4474、0.5526。未发现ACP_1~C基因及其它稀有基因。研究表明,ACP_1表型的分布存在着一定的种族与民族差异。     

Characterization of Senescence in Lemna gibba G3: A Determinate Growth System

Frond senescence in Lemna gibba G3 was characterized, and itscontrol by light, ABA and kinetin investigated. The plant exhibitsa determinate growth pattern with a frond producing a set numberof daughter fronds before undergoing senescence and death regardlessof whether or not it flowers. When a frond was cut in half,the distal half (half frond) which lacks any meristem underwentrapid senescence as compared with intact fronds. In both intactand half fronds, the onset of senescence was accelerated byABA and retarded by kinetin. Continuous white light acceleratedsenescence in both intact and half fronds over the dark controls.Under different photoperiodic light regime, the pace of daughterfrond production is accelerated in proportion to the lengthof light period. In half fronds, however, very short photoperiodiclight treatments (e.g. 1L: 23D or 3L: 21D) rather delayed senescenceover the dark controls. Two separate light control systems operatingin opposite directions in Lemana senescence appear to exist. ¹Present address: Department of Biology, Yonsei University,Seoul 120-749, Korea ²Present address: U.S. Department of Agriculture, Aero SpaceBuilding, Rm. 323, 901 D Street, S.W., Washington, D.C. 20251-2200, U.S.A. (Received July 13, 1989; Accepted May 8, 1990)     

丝裂素活化蛋白激酶参与内皮素刺激的兔主动脉平滑肌细胞增生

内皮素（ｅｎｄｏｔｈｅｌｉｎ,ＥＴ）是已知的体内活性最强的缩血管物质,其缩血管作用由Ｇ蛋白偶联受体所介导。但ＥＴ强大的促血管平滑肌细胞（ＶＳＭＣ）增生效应的机理尚未完全阐明。本研究选用培养的兔胸主动脉ＶＳＭＣ,探讨丝裂素活化蛋白激酶（ＭＡＰＫ）在ＥＴ促细胞增生中的作用。结果表明：ＥＴ－１呈时间和浓度依赖性地促进细胞摄取￣３Ｈ－ＴｄＲ和激活ＭＡＰＫ,此作用可被蛋白激酶Ｃ（ｐｒｏｔｅｉｎｋｉｎａｓｅＣ,ＰＫＣ）抑制剂Ｓｔａｕｒｏｓｐｏｒｉｎｅ（ＳＴＰ）,Ｈ－７和ＥＴ＿Ａ受体拮抗剂ＢＱ１２３所抑制,但不被酪氨酸激酶抑制剂ＨｅｒｂｉｍｙｃｉｎＡ（Ｈｅｒｂ）所抑制,用ＰＫＣ激动剂ＰＭＡ（Ｐｈｏｒｂｏｌｍｙｒｉｓｔａｔｅａｃｅｔａｔｅ）预处理ＶＳＭＣ,使其ＰＫＣ活性下调,可显著减弱ＥＴ－１对ＭＡＰＫ的激活能力。本结果提示：（１）ＭＡＰＫ参与ＥＴ－１所致的ＶＳＭＣ增生;（２）ＥＴ－１促细胞增生与激活ＭＡＰＫ的作用是由ＥＴ＿Ａ受体和ＰＫＣ介导的。     

Flooding-induced membrane damage, lipid oxidation and activated oxygen generation in corn leaves

Flooding effects on membrane permeability, lipid peroxidation and activated oxygen metabolism in corn (Zea mays L.) leaves were investigated to determine if activated oxygens are involved in corn flooding-injury. Potted corn plants were flooded at the 4-leaf stage in a controlled environment. A 7-day flooding treatment resulted in a significant increase in chlorophyll breakdown, lipid peroxidation (malondialdehye content), membrane permeability, and the production of superoxide (O ₂ ^- ) and hydrogen peroxide (H₂O₂) in corn leaves. The effects were much greater in older leaves than in younger ones. Spraying leaves with 8-hydroxyquinoline (an O ₂ ^- scavenger) and sodium benzoate (an .OH scavenger) reduced the oxidative damage and enhanced superoxide dismutase (SOD) activity. A short duration flooding treatment elevated the activities of SOD, catalase, ascorbate peroxidase (AP), and glutathione reductase (GR), while further flooding significantly reduced the enzyme activities but enhanced the concentrations of ascorbic acid and reduced form glutathione (GSH). It was noted that the decline in SOD activity was greater than that in H₂O₂ scavengers (AP and GR). The results suggested that O ₂ ^- induced lipid peroxidation and membrane damage, and that excessive accumulation of O ₂ ^- is due to the reduced activity of SOD under flooding stress.     

关养密度和成年雄鼠填充物的气味对黄毛鼠(Rattus rattoides)的发育和性成熟的影响(英文)

黄毛鼠（Ｒａｔｔｕｓ ｒａｔｔｉｄｅｓ）在群居（４只／笼）时体重及性器官,如睾丸和附睾的增长都受到了极大的抑制;血清中睾酮含量的迅速上升以及成熟精子在附睾的曲细精管中出现的时间也比单独关养的晚。成年雄鼠的笼填充物的气味能够诱导幼年雄鼠体重,睾丸的总量和长度以及血清中睾酮的含量的增加。     

三种鱼类生长激素cDNA基因的结构比较研究

从厦门海区选取３种生长速度不同的鱼类,真鲈、高体Ｓｈｉ、褐菖Ｙｏｕ,由它们的脑下垂体中分别提取出总ＲＮＡ,用逆转录ＰＣＲ方法（ＲＴ－ＰＣＲ）扩增出生长激素ｃＤＮＡ,克隆到ｐＢｌｕｅｓｃｒｉｐｔ载体上的ＥｃｏＲＩ位点,并分别测定了这３种鱼的成熟生长激素ｃＲＮＡ序列。将由这３种序列推导出的氨基酸序列同已知的８种不同科鱼类的生长激素氨基酸序列进行比较,分析它们序列的同源性,结果表明它们间的同源性与这些鱼     

狂犬病毒“北京株”在地鼠肾传代细胞中增殖的电镜观察

用透射电子显微镜观察术,对狂犬病固定毒“北京株”在地鼠肾传代细胞（ＢＨＫ２１）中增殖的形态学变化进行了研究。在受感染的细胞中有大量子弹状和长杆状的病毒颗粒。大多数病毒在扩张的内质网膜上以出芽的方式发生,凸向内质网腔内并逐渐发育成子弹状和杆关的成熟病毒。含病的内质,多周围常伴有颗粒或丝状均质区域,少数病毒在细胞膜上芽生。细胞间隙中亦可见病毒。还见病毒在细胞核膜内、外层上芽生,核周围间隙中许多病毒,有