五唇兰珠心细胞程序死亡的超微结构观察

应用透射电子显微镜观察了五唇兰珠心细胞程序死亡过程.五唇兰珠心细胞程序死亡超微结构的特征是：染色质凝集;线粒体结构简化,内嵴减少或消失;液泡数量增多,在一些液泡内含有细胞组分的碎片或膜状结构.     

Cholinergic, monoaminergic and glutamatergic changes following perinatal asphyxia in the rat

Perinatal asphyxia (PA) is considered to lead to a variety of brain disorders including spasticity, epilepsy, mental retardation, and minimal brain disorder syndromes and may form the basis for psychiatric and neurodegenerative diseases later in life. We examined markers for neuronal transmission involved in the pathomechanisms of PA and candidates as mediators for long-term sequelae. We tested tyrosine hydroxylase (TH) and the vesicular monoamine transporter (VMAT) representing the monoaminergic system, the vesicular acetylcholine transporter (VAChT), and the excitatory amino acid carrier 1 (EAAC1), a neuronal subtype of the glutamate transporter, using immunohistochemistry on brain sections of rats subjected to graded PA. Three months following the asphyxiant insult immunoreactive (IR)-TH was decreased in striatum, hippocampus, thalamus, frontal cortex, and cerebellum; IR-VMAT was increased, and IR-VAChT was decreased in striatum. IR-EAAC1 glutamate transporter was increased in frontal cortex. The cholinergic, monoaminergic, and glutamatergic changes, still observed 3 months after the asphyxiant insult, may reflect their involvement in the pathomechanisms of PA and indicate mechanisms leading to long-term complications of PA. The variable consequences on the individual markers in several brain regions may be explained by specific susceptibility of cholinergic, monoaminergic, and glutamatergic neurons to the asphyxiant insult. Received 16 March 1999; received after revision 20 May 1999; accepted 8 July 1999     

具有突变率的广义生-灭过程的唯一性

给出具有突变率的广义生－灭过程的唯一性的充分必要条件。     

具有突变率的广义生-灭过程的遍历性

给出具有突变率的广义生-灭过程的遍历与指数遍历的充分必要条件，以及强遍历的充分条件。     

铜离子金属胶束介质中PNPA水解的动力学研究

研究了25℃时，铜离子与二胺类配体DMEA和DMPA(DMEA为N，N－二甲基乙二胺，DMPA为N，N－二甲基－1,3－丙二胺)形成的配合物对PNPA(对硝基苯酚乙酸酯)催化水解的动力学，并通过了胶束催化的二元复合物动力学模型对其进行定量处理，结果表明，铜离子与不同的二胺类配体形成的配合物在CTAB胱束溶液中对PNPA的催化水解表现出不同的催化效果，而催化的机理则可能是由于与铜离子配位的水分子去质子化以后形成的亲核体对PNPA进行亲核进攻的结果。     

含二烷基硫代甲酰胺桥基配体的三核铁羰基硫簇合物的合成和表征

Ｆｅ（ＣＯ）１２与双（二烷基氨基硫代甲酰基二硫）Ｒ２ＮＣ（Ｓ）Ｓ２Ｃ（Ｓ）ＮＲ２（Ｒ＝Ｍｅ,Ｅｔ,ｉ－Ｐｒ,ＮＲ２＝ＮＣ５Ｈ５）反应,得到四个新的含前配体劈开的Ｓ,ＳＣＮＲ２和ＮＲ２配位分子的三核铁羰基族合物,并对其进行了元素分析及ＩＲ,＾１ＨＮＭＲ和ＭＳ谱学表征。它们是Ｆｅ３（ＣＯ）６（μ３－Ｓ）２（μ,η＾２－ＳＣＮＲ２）２（μ－ＮＲ２）（Ⅰ：Ｒ＝ＣＨ３,Ⅱ：Ｃ２Ｈ５）;Ｆｅ３（ＣＯ）８（μ３     

钙离子可能参与放线菌素D诱导的玉米细胞凋亡

钙在动物细胞凋亡的信号转导中起重要作用,其最直接的作用是激活钙依赖性核酸酶,导致DNA的特异片段化.然而,关于钙在植物细胞程序性死亡中的作用的报道很少.本文以玉米根尖分生组织为材料,利用RNA合成剂放线菌D诱导细胞死亡,并从形态和生化方面检测到这种细胞死亡是一种程序性死亡(programmed cell death,PCD).利用钙离子特异性结合荧光染料wazo-1研究的结果表明,在死亡程序启动的瞬间,胞质内钙离子浓度急骤上升.意味着钙信号转导途径可能参与了这种PCD.这种PCD在DNA严重断裂之前是可以逆转的.     

新型亲和活性配基及其纯化功能

以Ｄ．Ｓ．Ｄ．酸为桥基，氯三嗪为活性基，对－氨基苯甲酸、对－氨基苄基膦酸、对－氨基苯磺酸为尾基合成了三只对称型无色活性配基，其结构经波谱法及色谱法验证；比较了它们对碱性磷酸酶的纯化功能。结果表明：以苯甲酸及苄基膦酸作尾基者效果较好，回收率达８０％以上；配基浓度及缓冲液ｐＨ值对回收率影响明显。     

三元表面配合物的研究综述

本文从三元表面配合物的相关研究、生成与分类、研究方法、研究内容及现状等几方面对液／固界面三元表面配合物的研究进行了综述．