着两种防护装备加压呼吸时的心血管反应

在 12 0 0 0ｍ以上飞行时 ,如座舱失密封 ,为防止缺氧必需采取吸纯氧加压呼吸 (ｐｏｓｉｔｉｖｅｐｒｅｓｓｕｒｅｂｒｅａｔｈｉｎｇ ,ＰＰＢ)。ＰＰＢ对机体产生一系列的不良影响 ,其中最主要的是对心血管的影响。ＰＰＢ同时使用防护装备 ,能够对抗ＰＰＢ的影响。这种防护装备按其结构分为囊式和管式两种 ,囊式装备在西方国家已应用多年。我国长期沿用前苏联的管式装备。随着高性能战斗机的发展 ,囊式装备在抗荷方面的优势已得到证实 ,代偿性能尚不明确。为此我们对我国新研囊式防护装备 (ＤＫＴ ｓｕｉｔ 1)样件 ,进行地面加压呼吸 ,以管…     

牛胰多肽（BPP）二级结构的红外光谱和圆二色谱分析

牛胰多肽（ｂｏｖｉｎｅｐａｎｃｒｅａｔｉｃｐｏｌｙｐｅｐｔｉｄｅ,ＢＰＰ）是胰脏分泌的一种含有３６个氨基酸的多肽［１］,ＢＰＰ能预防和治疗由胆酸盐诱发的大鼠急性胰腺炎,具有细胞保护作用。本文用傅里叶变换红外光谱（ＦＴ－ＩＲ）和圆二色谱（ＣＤ）,对ＢＰＰ在水溶液中的二级结构进行了研究。两种方法的分析结果互相补充,进一步确定了ＢＰＰ在溶液状态的二级结构。本研究为进一步探讨ＢＰＰ抑制膜融合的机理打下了基础。     

牛胰多肽（BPP）二级结构的红外光谱和圆二色谱分析

牛胰多肽（ｂｏｖｉｎｅ ｐａｎｃｒｅａｔｉｃ ｐｏｌｙｐｅｐｔｉｄｅ，ＢＰＰ）是胰脏分泌的一种含有３６个氨基酸的多肽「１」，ＢＰＰ能预防和治疗由胆酸盐诱发的大鼠急性胰腺炎，具有细胞保护作用。本文用傅里叶变换红外光谱（ＦＴ－ＩＲ）和圆二色谱（ＣＤ），对ＢＰＰ在水溶液中的二级结构进行了研究，两种方法的分析结果互相补充，进一步确定了ＢＰＰ在溶液状态的二级结构，本研究为进一步探讨ＢＰＰ抑制膜融合的机理打下     

银胶溶液的pH值对DpNPV-PP表面增强拉曼光谱的影响

比较了马尾松毛虫核型多角体病毒多角体蛋白（ＤｐＮＰＶ－ＰＰ）这种昆虫病毒蛋白在ｐＨ值不同的银胶溶液中的表面增强拉曼光谱。在中ｐＨ值溶液中,ＤｐＮＰＶ－ＰＰ主要通过硫氢基团和羧基基团吸附于银表面。在低ｐＨ值溶液中,硫氢基团的吸附作用趋弱,ＤｐＮＰＶ－ＰＰ主要通过羧基基团和氨基基团与银粒子表面键联,并以阴离子构型［ＮＨ２ＲＣＯＯ－］存在于溶液中。而在高ｐＨ值溶液中,仅有羧基基团与银表面的吸附作用较强。不同ｐＨ值条件下,低波数带２３８ｃｍ－１～２２６ｃｍ－１的出现,均表明ＤｐＮＰＶ－ＰＰ与银表面产生明显的化学吸附。ＤｐＮＰＶ－ＰＰ在银胶中的增强属于分子增强机制,具有短程作用特性。银胶溶液ｐＨ值的改变,引起被吸附基团与银表面之间的吸附方式、相对距离、相对几何状态等因素发生改变,导致了不同ｐＨ值条件下拉曼散射增强效果的不同。     

新型生长抑肽对成纤维细胞的DNA合成及某些癌基因表达的影响

从细胞水平和基因水平研究了新型生长抑肽（ＥＰＰ）的生物学作用,研究表明：ＥＰＰ对ＮＣ３Ｈ１０及ＴＣ３Ｈ１０细胞的ＤＮＡ合成均有抑制作用,当ＥＰＰ与ｃＡＭＰ的位点选择性类似物８－Ｂｒ－ｃＡＭＰ共同作用时,其对ＮＣ３Ｈ１０细胞的ＤＮＡ合成的抑制作用消失,而对ＴＣ３Ｈ１０仍具有抑制作用;核酸杂交分析表明,ＥＰＰ可以抑制ｃ－ｆｏｓ、ｎｅｕ、ｋｉ－ｒａｓ三类癌基因在转化细胞中的表达。证明了ＥＰＰ对转化细胞的生长具有一定的抑制效应,且与８－Ｂｒ－ｃＡＭＰ联合使用时其效果更佳。     

牛胰多肽与CL／PC脂质体作用后二级结构的变化

用傅立叶变换红外光谱研究了ＢＰＰ与膜作用后其二级结构的变化,通过对红外光谱中酰胺Ｉ谱带进行解卷积、微分及曲线拟合等处理,结果表明,ＢＰＰ与脂膜作用后,其二级结构中α－螺旋成分增多,无规卷曲成分减少。     

加压对茶叶加工中酶活力影响的研究

本试验验采用调控大气压力的物理方法,研究了在红茶制作过程中加压与多酚氧化酶、α—淀粉酶、转化酶、蛋白水解酶活力强弱的关系。结果发现：加压能提高这四种酶活力,且在一定范围内随压力增加和加压时间延长,其活力均提高。同时,又研究了压力对多酚氧化酶（ＰＰＯ）同工酶活力的影响。结果发现：ＰＰＯ１、ＰＰＯ２的活力有较小幅度的提高,ＰＰＯ３基本没有变化,ＰＰＯ４、ＰＰＯ５、ＰＰＯ６随加压时间延长,活力呈大幅度提高。     

单克隆抗体ELISA测定UVB诱导的DNA损伤

本文采用单克隆抗体酶联免疫吸附分析法测定了ＵＶ－Ｂ诱导ＤＮＡ产生的ＣＰＤ和６－４ＰＰ。经０．５ｍＷ／ｃｍ＾２ＵＶ－Ｂ处理１５ｍｉｎ的小牛胸物鲱鱼精ＤＮＡ,ＣＰＤ和６－４ＰＰ含量显著增加,而未经ＵＶ－Ｂ处理的对照ＤＮＡ则没有二聚体形成。     

肺炎链球菌培养研究

从５种肺炎链球菌液体培养基中,选择出ＢＹＧＰＰ－ｇｌｕ培养基,与国外常用的ＢＨＩ培养基相比,细菌生长良好,便于规模生产。并对肺炎链球菌生长特性作了探讨,表明维持一定的糖浓度、ｐＨ值、ＣＯ２供应量以及适宜的培养时间,是肺炎链球菌培养成功与否的主要影响因素。本文还对肺炎链球菌工作菌种的实验室保存方法进行了研究。     

人肺癌细胞CPP32基因的克隆及表达

蛋白酶尤其是ＩＣＥ家族的蛋白酶是细胞死亡机制的核心成分．ＩＣＥ蛋白酶家族中,ＣＰＰ３２（又称Ｙａｍａ,ａｐｏｐａｉｎ）在不同形式的凋亡途径中起核心作用．为深入研究ＣＰＰ３２的结构与功能,克隆了ＣＰＰ３２基因,并在大肠杆菌中进行了表达．采用ＲＴ－ＰＣＲ技术从人肺癌细胞株中获得了ＣＰＰ３２蛋白酶基因．ＤＮＡ序列分析表明,该基因由已报道的编码ＣＰＰ３２αｐ２０亚单位和ＣＰＰ３２βｐ１０亚单位的核苷酸组成,提示ＩＣＥ家族蛋白酶寡聚化可能受ＤＮＡ水平调控．将获得的ＣＰＰ３２基因分别重组到ｐＢＶ３２１和ｐＥＸ３１Ｂ载体上,并分别转化到大肠杆菌中,均获得了ＣＰＰ３２基因的较高表达,表达产物主要以包涵体形式存在．     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.     

肝癌中HBV和HCV基因和抗原的分布及意义

采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细     

Selection with two alleles and complete dominance

For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.