我国参加第4届IBO工作总结

我国参加第４届ＩＢＯ工作总结吴相钰,刘恩山ＩＢＯ是国际中学生生物学奥林匹克竞赛（ＩｎｔｅｒｎａｔｉｏｎａｌＢｌｏｌｏｓｖＯｌｖｍｎｉａｄ）的缩写。第１届ＩＢＯ于１９９０年在捷克举行,第２届１９９１年在前苏联举行,第３届１９９２年又于斯洛伐克举行。第２...     

武汉地区1988—1992年呼吸道合胞病毒流行株的抗原性分析

利用呼吸道合胞病毒的单克隆抗体,通过间接免疫荧光法和免疫转印法对本室分离到的武汉地区１９８８－１９９２年的５６份ＲＳＶ毒株进行了分型,可将其分为Ａ、Ｂ两型和Ｂ１、Ｂ２亚型,流行病学分析显示：本地区ＲＳＶ的主要流行株,四年中有三年为Ｂ型株。不同于欧美等地;Ａ、Ｂ两型的分布还具有灶化分布的特点;两型在性别、发病年龄之间无显著性差异。     

蛋白激酶B的研究进展

蛋白激酶Ｂ(ＰＫＢ)发现于1991年,因其激酶活性区的氨基酸组成与蛋白激酶Ａ(ＰＫＡ)和蛋白激酶Ｃ(ＰＫＣ)高度同源而得名。初步研究表明,ＰＫＢ激酶活性的调节与细胞的生命活动密切相关,如ＰＫＢ参与某些生长因子或淋巴因子诱导的靶细胞应答,影响胞内糖类的转运、糖原的合成及蛋白质的合成,抑制细胞凋亡等。ＰＫＢ是机体维持正常生命活动的一个重要调节子。1.ＰＫＢ的结构与分类1991年三个不同的研究小组同时发现ＰＫＢ蛋白,并证明其激酶活性区的氨基酸组成与ＰＫＣε和ＰＫＡ的同源性分别为73%和68%,因此将其命名为ＰＫＢ或ＲＡＣＰＫ(ｒｅ…     

棉铃虫触角气味物质结合蛋白的鉴别

昆虫触角内的气味物质结合蛋白ｏｄｏｒａｎｔ－ｂｉｎｄｉｎｇｐｒｏｔｅｉｎ（简称ＯＢＰ）是触角嗅觉感受器淋巴液中的一类水溶性蛋白质,能和气味物质结合。ＯＢＰ的发现可追溯到１９７０年,美国科学家Ｒｕｄｄｉｆｏａｄ根据实验,推断触角中有某种蛋白质,和嗅觉有关~（［１］）。１９８１年Ｖｏｇｔ和Ｒｉｄｄｉｆｏａｌ用标记激素证明了上述推论的正确性,把它称为外激素结合蛋白（ｐｈｅｒｏｍｏｎｅ－ｂｉｎｄｉｎｇｐｒｏｔｅｉｎ,缩写为ＰＢＰ）~（［２］）。１９９０年Ｂｒｅｅｒ报道了另一类ＯＢＰ──普通气味物质结合蛋白…     

第三届IUBMB学术大会消息

第三届ＩＵＢＭＢ学术大会消息国际生化与分子生物学联合会（ＩＵＢＭＢ）第三届学术大会（３ｒｄＩＵＢＭＢＣｏｎｆｅｒｅｎｃｅ）定于１９９５年４月２３一２７日在新加坡举行,主题为“分子识别”。５个大会报告中包括Ａ．Ｒ,Ｆｅｒｓｈｔ教授的“蛋白质折叠”;Ｄ．...     

12057单体系及其二体抗旱生理指标的比较

利用１２０５７单体及其二体连续两年进行抗旱生理招标的比较,结果表明：１２０５７单体系珉春二体在灌浆中期旗叶相对含水量、细胞膜稳定性、叶片渗透势以及渗透调节能力等均存在差异。其中２Ｂ、３Ｂ、６Ｂ单体相对含水量较高;５Ａ单体叶组织膜稳定性较高;４Ｂ、５Ｂ、４Ｄ、６Ｂ、３Ａ单体的渗透势较低;６Ｂ、４Ｂ、３Ｂ、４Ｄ、、Ｂ单体的渗透调节能力较高。此外看出部分同源染色体群对上述生理招标的反应具有相似性。     

昆虫学文献索引检索途径介绍(4):《CAB文摘数据库》

ＣＡＢＩ(或ＣＡＢＩＮＴＥＲＮＡＴＩＯＮＡＬ)是设在英国的国际组织———国际农业和生物科学中心 (ＣｅｎｔｒｅｆｏｒＡｇｒｉｃｕｌｔｕｒｅａｎｄＢｉｏｓｃｉｅｎｃｅｓＩｎｔｅｒｎａｔｉｏｎａｌ)的简称 ,其原名为英联邦农业局 (ＣｏｍｍｏｎｗｅａｌｔｈＡｇｒｉｃｕｌｔｕｒａｌＢｕｒｅａｕｘ) ,成立于 1 92 9年 ,1 985年更名为国际英联邦农业局 (ＣｏｍｍｏｎｗｅａｌｔｈＡｇｒｉｃｕｌｔｕｒａｌＢｕｒｅａｕｘＩｎｔｅｒｎａｔｉｏｎａｌ) ,1 993年改为现名。其主要任务是为农业、生物信息与科研提供服务。由该中心提供的《…     

周志炎院士获B.Sahni百年纪念奖

周志炎院士获Ｂ．Ｓａｈｎｉ百年纪念奖中国科学院南京地质古生物研究所研究员周志炎院士获１９９５年度Ｂ．Ｓａｈｎｉ百年纪念奖,并于１９９６年１月２５日在印度勒克垴市参加授奖大会。Ｂ．Ｓａｈｎｉ是世界著名的古植物学家,印度古植物学的创始人和奠基人,英国皇家...     

新疆哈密寒气沟墓地出土颅骨的研究

新疆考古所文物队于１９９４年在哈密地区寒气沟墓地发掘出４座墓葬共３具颅骨,其中一具男颅,两具女颅,编号为９４ＨＴＢＩＭ３：Ｂ（男颅）、９４ＨＴＢＨＩＭ２：Ｂ（女颅）、９４ＨＴＢＨＩＭ３：Ａ（女颅）。据文物判定其时代为春秋时期。在考古文化上与焉布拉克相...     

中国－欧共体生物技术中心（CEBC）成立两年来的回顾

中国－欧共体生物技术中心（ＣＥＢＣ）成立两年来的回顾丁一明（中国－欧共体生物技术中心）中国－欧共体生物技术中心（Ｃｈｉｎａ—Ｅｕ－ｒｏｐｅａｎＣｏｍｍｕｎｉｔｅｓＢｉｏｔｅｃｈｎｏｌｏｇｙＣｅｎｔｅｒ）已成立两周年了。两年多来,ＣＥＢＣ这一双边合作机...     

沙门菌CWDMs乳酸脱氢酶同功酶的观察

采用聚丙烯酰胺凝胶电泳法检测伤寒杆菌和甲型副伤寒杆菌的ＣＷＤＭｓ及其宁代细菌型和伤寒杆菌粗糙型的乳酸脱氢酶（ＬＤＨ）同功酶,以了解沙门菌ＣＷＤＭｓ生物氧化的特点和机制,探讨ＣＷＤＭｓ变异的性质。结果表明,伤寒杆菌和甲型副伤寒杆菌的细菌型及伤寒杆粗糙型在聚丙烯酰胺凝胶电泳后显示出相同的４种具有不同泳动速率的ＬＤＨ同功酶,但ＣＷＤＭｓ仅显示２种ＬＤＨ。ＣＷＤＭｓ的２种ＬＤＨ同功酶与其亲代细菌型及伤寒杆     

省沽油科叶解剖结构的分类学意义

本文对国产省沽油科 Staphyleaceae 4属植物叶的解剖结构进行了详细的比较研究。结果表明, 叶解剖结构特征在属间的区别较明显, 特别是瘿椒树属 Tapiscia 有着几乎与其他三属截然不同的独特性状。根据已有的孢粉学, 花、节及木材的解剖等方面的资料, 我们支持Тахтаджян(1987)将瘿椒树亚科分出而建立瘿椒树科 Tapisciaceae 的观点。瘿椒树属为我国特有属, 根据我们对采自不同产地的材料观察, 居群间的差异很小, 其可能仍为一单种属。     

中国鳐类脑颅的研究

作者解剖观察了33种,隶于4目、7亚目、15科、19属的中国鳐类脑颅的形态。研究结果认为:锯鳐目和鳐目是原始类群,它们均具吻软骨,其中圆犂头鳐科和团扇鳐科是特化类群。电鳐目亦具吻软骨,它们是特化和退化类群。在较高等的鲼目则无吻软骨。依据鳐类不同的分类阶元,其脑颅亦各具有不同的式型。     

ASCOCARPIC CENTRUM ONTOGENY OF SPECIES OF HYPODERMATACEAE OF CONIFERS

Studies on the morphology of the ascocarps of 39 species of Hypodermataceae revealed several previously unknown cytological features. Two basic and one intermediate type of centrum ontogeny are discussed. Ascal initiation within Type I centrum occurs in the basal cells of the pseudoparaphyses and involves anastomoses, while ascal initiation within Type II occurs in cells of a plectenchymatous centrum, with no visible anastomosing in the ascocarp. There is frequent anastomosing between vegetative hyphae well in advance of initiation of the ascocarp. Ascal initiation in the intermediate type has ontogenetic sequences similar to those in Types I and II.     

沙门菌CWDMs苹果酸脱氢酶的检测

目的：了解沙门菌细菌壁缺陷突变株（CWDMs）的生物氧化及遗传特点和探讨细菌壁缺陷变异的性质与机制。方法：采用PAGE电泳法和分光光度法检测伤寒沙门菌和甲型副伤寒沙门菌及其CWDMs和伤寒沙门菌粗糙型和苹果酸脱氢酶（MDH）同工酶的活性与类型。结果：伤寒沙门菌和甲型副伤寒沙门菌的细菌型和伤寒沙门菌粗糙型经PAGE电泳可见一条MDH同工酶带,CWDMs电泳后可见两条MDH同Ⅰ酶带,在CWDMs的MDH中有一条泳动速率与细菌型及粗糙型的相同,另一条则较快。分光光度法检测证实。细菌型与粗糙型的MDH活性相似,CWDMs的MDH活性则明显较低。结论：CWDMs保留了与亲代细菌型一致的MDH和形成了一种新的MDH,并且其MDH的活性已显著降低,此特性可能与CWDMs生物氧化特性的改变有关。     

沙门菌CWDMs脂代谢检测

采用毛地黄皂苷敏感试验和菌细胞胆固醇、甘油三脂及胆碱酯酶定性与定量分析法,检测伤寒杆菌和甲型副伤寒杆菌经L 型变异后形成的细胞壁缺陷突变株(CW DM )的脂类代谢活性,了解这些CW DM 变异的性质和探讨细菌细胞壁缺陷突变与细菌演变的关系。结果表明,沙门菌CW DM s 具有显著的胆固醇和甘油三脂代谢活性、对毛地黄皂苷高度敏感并且还具有与白色念珠菌相似的胆固醇和甘油三脂的含量,但未能检出胆碱酯酶活性。CW DM s返祖菌丧失了脂类代谢酶类和胞浆膜不含胆固醇,恢复了与其亲代细菌型相似的代谢特征。提示在沙门菌天然即存在有与脂类及胆固醇代谢相关的基因,细胞壁的缺陷导致这些脂类及胆固醇代谢基因活化,以致 CW DM s 能够表达固醇和甘油三脂代谢活性和胞浆膜含有胆固醇     

ULTRASTRUCTURE OF AUXIN-INDUCED TUMORS OF THE COLEORHIZA-EPIBLAST OF WHEAT

When wheat is germinated in high concentrations of certain auxins, the coleorhiza-epiblast grows in an excessive and disorganized manner and resembles a callus. Wheat was germinated in 10⁻³ M indoleacetic acid or in water. There was greater net synthesis of DNA, RNA, and protein in the tumor tissue than in control tissue. Control and tumor tissue was fixed for electron microscopy 1, 2, 3, and 4 days after sowing. In contrast to the controls, many more lipoidal bodies appeared in 1-day-old, auxin-treated tissue and thereafter diminished in number. In 2- and 3-day-old tumor tissue, small membraneous fragments were prominent but disappeared in older tissue. With time, the following changes became progressively more pronounced: cytoplasmic vacuolation, appearance of myelin figures, polyribosome configurations and extensive profiles of rough endoplasmic reticulum, and sloughing of cytoplasmic contents into and accumulation of electron-dense material in vacuoles. Possible factors in susceptibility of certain tissues to tumor formation are discussed.     

STABILITY OF SUSPENSIONS OF SOLID PARTICLES OF PROTEINS AND PROTECTIVE ACTION OF COLLOIDS

1. It is shown that the concentrations of different salts required to precipitate suspensions of gelatin-coated collodion particles in water are practically identical with the concentrations of the same salts required for the "salting out" of gelatin from aqueous solutions. Neither effect shows any relation to the electrical double layers surrounding the particles. 2. It is shown that at the isoelectric point of gelatin, suspensions of gelatin-coated collodion particles are not stable and it had been shown previously that gelatin is least soluble at the isoelectric point. The addition of salt increases both the solubility of gelatin in water as well as the stability of suspensions of gelatin-coated collodion particles in water, and both effects increase with the valency of one of the ions of the salt. 3. This latter effect is not due to any charges conferred on the gelatin particles by the salts, since the cataphoretic experiments show that salts like NaCl, Na₂SO₄, or CaCl₂, which at the isoelectric point of gelatin increase the solubility of gelatin as well as the stability of suspensions of gelatin-coated collodion particles, leave the particles practically uncharged in the concentrations in which the salts are efficient. 4. It follows from all these facts that the stability of suspensions of gelatin-coated particles in water depends on the solubility of gelatin in water; e.g., on the chemical affinity of certain groups of the gelatin molecule for water. 5. Though crystalline egg albumin is highly soluble in water, the stability of collodion particles coated with crystalline egg albumin does not depend upon the affinity of the albumin molecule for water, but depends practically alone on the electrical double layer surrounding each particle. As soon as the P.D. of this double layer falls below 13 millivolts, the suspension is no longer stable. 6. The critical potential for the stability of suspensions of collodion particles coated with genuine egg albumin is the same as that for particles of boiled (denatured) white of egg. Since through the process of heating, egg albumin loses its solubility in water, it is inferred that egg albumin undergoes the same change when it forms a film around a solid particle like collodion. 7. The influence of electrolytes on the stability of suspensions of collodion particles coated with casein or edestin was similar to that of collodion particles coated with egg albumin. The experiments are, however, complicated by the fact that near the isoelectric point CaCl₂ and even NaCl cause a suspension again at concentrations of about M/2 or 1 M, while still higher concentrations may cause a precipitation again. These latter effects have no connection with double layers, but belong probably in the category of solubility phenomena. 8. These experiments permit us to define more definitely the conditions for a general protective action of colloids. Protective colloids must be capable of forming a durable film on the surface of the suspended particles and the molecules constituting the film must have a higher attraction for the molecules of the solvent than for each other; in other words, they must possess true solubility. Only in this case can they prevent the precipitating action of low concentrations of electrolytes on particles which are kept in suspension solely by the high potentials of an electrical double layer. Thus gelatin films, in which the attraction of the molecules for water is preserved, have a general protective action, while crystalline egg albumin, casein, and edestin, which seem to lose their attraction for water when forming a film, have a protective action only under limited conditions stated in the paper.     

合浦珠母贝珍珠的生物学性能初步检测

本研究报道了合浦珠母贝珍珠的生物学性能初步检测结果。珍珠作为—种天然的生物材料。在医药、化妆品工业等领域中的应用已很广泛。本研究对合浦珠母贝珍珠进行了体外细胞毒性试验、溶血试验和经静脉全身急性毒性试验的研究。实验结果表明,合浦珠母贝珍珠具有较好的细胞相容性,其浸提液对实验动物无明显毒性。在本研究中,合浦珠母贝珍珠的浸提液对兔血红细胞的溶血指数高于对照组。     

刺激迷走神经向中端对大鼠不同脑区脑啡肽含量的影响

自从1975年(Hughes et al. 1975)发现脑啡肽以来,经多方面研究已认为脑啡肽可能是一种神经递质,它具有多种生理功能(范少光、汤健,1978)。据新近文献报道,脑啡肽与催产素及加压素三者具有共同存在的并存关系(Martin and Voigt。1981)。 已经证明,刺激迷走神经向中端,可引起脑内释放乙酰胆硷,从而促使神经垂体释放压加素和催产素,肾上腺释放肾上腺素(Chang, et al. 1937;1961,1964;吕运明等1965,1977;唐正荣1981)。但是,刺激迷走神经向中端,是否也能引起脑内脑啡肽的释放,迷走神经传入纤维与脑内脑啡肽能神经原之间,是否存有机能上的联系?关于这个