拟毛突摇蚊属二新种及一新纪录种记述(双翅目:摇蚊科)

拟毛突摇蚊属Paratrichocladius Santos Abreu 1918隶属于直突摇蚊亚科Ortho-cladinae,迄今全世界已知十余种。Hirvenoja(1973)对本属进行了整理。本文的记载为此属在我国的首次记录。 属征:复眼小眼面间密生细毛,触角比(AR)通常大于1;翅无大毛,腋瓣是多数缘毛;肩陷中等大小,背中鬃多数;无肛尖,抱器基节具一明显的上内突。 本文记述了采自吉林、四川省的2个新种和1个新纪录种。模式标本存南开大学生物学系。     

植物单盐毒害和离子拮抗机理研究Ⅰ.单盐和混合盐对植物原生质体膜某些特性、超氧物歧化酶和过氧化氢酶活性的影响

单盐(KCl, CaCl_2或MgCl_2)和混合盐(KC_1+CaCl_2或KCl+MgCl_2)对植物原生质体完整率、存活率和膜透性等均有明显影响。K~+、Ca~(2+)或Mg~(2+)等单种阳离子明显降低原生质体膜完整率和存活率而增加其物质渗漏量,其中以单价阳离子K~+的影响为甚。上述单种阳离子还明显降低小麦幼叶超氧物歧化酶(SOD)和过氧化氢酶活性。只有由单价和二价阳离子组成的平衡混合盐才能使原生质体维持较高的完整率、存活率和较正常的膜透性.并能使细胞维持较高的SOD和过氧化氢酶活性。 认为单盐毒害机理可能是首先引起细胞膜发生不正常的膜相变或细胞累积较多的有害氧自由基,引起膜脂发生过氧化或脱酯化而破坏膜结构。在离子平衡混合盐作用下,膜系才能维持正常液晶相,具有较高活性的SOD和过氧化氢酶等生物保护性酶系是离子拮抗作用之原因。     

桂西壮族手皮纹的分析

本文对广西西部500例健康壮族大、中学生的手皮纹进行了观察分析,计算出各型指纹频率、指纹脊线总数、指纹频度指数、atd角度、a-b脊线数、τ距比、主线横向指数、皮纹花样出现率、掌褶纹出现率共九项基本参数,并将这些数值与汉族作了比较,桂西壮族的手纹与汉族既有相似之处,又有本民族的特点。     

黑质升压和弓状核降压效应及二者间的机能联系

本工作用神经元胞体兴奋剂L-谷氨酸钠(Glu)注入箭毒化、人工呼吸大鼠的下丘脑弓状核(AR),引起血压下降,心率减慢;多巴胺(DA)受体激动剂去水吗啡注入AR和Glu注入黑质(SN)均产生升压和加速心率的效应,Glu(i.SN)效应可被DA受体阻断剂氟哌啶醇注入双侧AR阻断;从而证明:(1)AR具有降压、降心率功能;(2)黑质可通过AR内的DA受体对AR降压、降心率效应起抑制作用,而实现其加压、加速心率效应。     

急性心肌缺血对血液流变学和心脏收缩功能改变的影响

在麻醉开胸狗观察了急性心肌缺血对血液流变学和心脏收缩功能改变的影响。在阻断狗前降支冠脉1h内,血液流变学各参数发生异常变化,表现为高、低切变率下全血粘度(ηbh、ηb1)、血浆粘度、血细胞压积和纤维蛋白原升高,红细胞电泳时间缩短。同步描记心电、心音和颈动脉搏动图而记录的心脏收缩时间间期,表现为射血前期(PEP)延长、左室射血时间(LVET)缩短和PEP/LVET比值增大。此外,动脉舒张压(DAP)升高,心输出量(CO)减少。上述各参数均与对照值有明显差异,P<0.05。缺血40min时,对ηb1和PEP/LVET或DAP进行相关分析,呈明显正相关,P<0.05;ηb1和CO呈明显负相关,P<0.01。结果提示,心肌缺血后发生的血液流变学异常变化,具有增加射血阻力和减少心输出量的作用。     

Production and characterization of a monoclonal antibody cross-reactive with most group A trichothecenes

A monoclonal antibody cross-reactive with most group A trichothecenes was produced by fusion of P3/NS-1/1-AG4-1 myeloma cells with spleen cells isolated from a BALB/c mouse that had been immunized with 3-acetyl-neosolaniol-hemisuccinate conjugated to bovine serum albumin. One stable clone, H159B1D5, which produced monoclonal antibody that bound with both T-2 toxin and diacetoxyscirpenol (DAS) was obtained after subcloning. Enzyme-linked immunosorbent assay (ELISA) revealed that the antibody belongs to the immunoglobulin G1 (kappa chain) isotype and had binding constants of 2.81 x 10(9), 1.05 x 10(9), and 1.57 x 10(8) liters per mole for T-2 tetraol tetraacetate, T-2 toxin, and DAS, respectively. The relative cross-reactivities of the antibody with T-2 tetraol tetraacetate, T-2 toxin, and DAS were 200, 100, and 20, respectively, with tritiated T-2 toxin as the marker ligand. The relative cross-reactivities for the above toxins were 667, 100, and 73, respectively, with tritiated DAS as the marker ligand. No cross-reaction with HT-2 and deoxynivalenol triacetate was observed in either system. By using this monoclonal antibody, an indirect ELISA for analysis of T-2 toxin was also developed. The linear portion of the standard curve for analysis of T-2 toxin in each analysis by radioimmunoassay and ELISA was in the range of 0.1 to 2 ng and 0.05 to 1.0 ng, respectively.     

Effects of traces of rare earth elements on the protozoanBlepherisma and on mice

The growth of the protozoanBlepherisma is stimulated by Lanthanum (La) at concentrations as low as 0.32 ppm. In mice Yttrium (Y) and Ytterbium (Yb) are absorbed, accumulated, and metabolized. Both rare earth elements (RE) exhibit a high affinity for teeth and bones, accumulation occurs and metabolism is slow. In the livers of RE-exposed mice, concentrations are variable. The liver is apparently capable of absorbing and discharging RE in a manner depending on metabolic activity. The main route of discharge for ingested REs is the alimentary canal. Exposure of pregnant mice to RE leads to rapid placental transfer of RE; 14.1% of the total amount of RE administered was detected in newborn mice. Young, developing organisms appear to be especially susceptible to RE accumulation.     

Cross-reactivity of antibodies against T-2 with deepoxide T-2 toxin

Two types of antibodies raised against T-2 toxin, namely anti-T-2-HS-BSA and anti-3 -Ac -NEOS-HS -BSA, showed good cross-reactivity with deepoxy T-2 toxin. Our results indicate that the epoxide is not an important epitope for the production of antibody against T-2 toxin     

Tubulin isotypes and their interaction with microtubule associated proteins

Summary To assay the functional significance of the multiple but closely related - and -tubulin polypeptides (termed isotypes) that are expressed in mammalian cells, we have generated a number of sera that uniquely discriminate among these isotypes. These sera have been used to demonstrate that there is no subcellular sorting of either - or -tubulin isotypes among microtubules of diverse function, either in cells growing in culture or in tissues consisting of cell types that contain specialized kinds of microtubule. In spite of this failure to segregate between functionally distinct kinds of microtubule, the fact that isotype-specific amino acid sequences have been strictly conserved over extensive periods of evolutionary time argues persuasively for a functional role for the different tubulin gene products. One possibility is that they are required for specific interactions with microtubule associated proteins (MAPs), and that tubulin isotypes have coevolved with different cell type-specific MAPs with which they must interact. We have tested this hypothesis by examining the distribution of -tubulin isotypes in mammalian cerebellum in relationship to the known patterns of expression of a number of MAPs, and find that these patterns correlate in the case of M 2 and MAP 3, and M 6 and MAP 1 a. These data, plus emerging data based on a structural analysis of tau, MAP 1 b and MAP 2 obtained via sequence determination of cloned cDNAs, are discussed in terms of the possible functional significance of tubulin isotype/MAP interactionsin vivo.