肺表面活性蛋白C基因异常与婴幼儿肺间质性疾病

肺表面活性蛋白C（surfactant protein C,SP-C）基因是目前被发现的唯一仅在肺泡Ⅱ型上皮细胞中表达的肺表面活性蛋白基因,其蛋白表达产物SP-C是构成肺表面活性物质的小分子疏水性蛋白之一,具有调节肺泡液.气界表面张力、维持肺表面活性膜的稳定及参与肺器官局部防御体系等重要的生理功能.SP-C基因异常可造成SP-C结构变化和功能丧失,从而导致各种婴幼儿肺疾病,其中,肺间质性疾病（interstitial lung disease,ILD）的发病与SP-C基因突变的关系尤为密切.     

表面活性物质有细胞保护作用

表面活性物质(surfactant)是一类磷脂化合物,能降低表面张力,是维持正常呼吸功能不可少的物质。既往认为,只有肺泡Ⅱ型细胞才能分泌这类磷脂;但近年来发现,它们也存在于胃粘膜上皮的表面。胃内的表面活性物质究竟有什么功用呢?这是近来很多学者想了解的问题。最近,美国Texas大学医学院Lich-tenberger等发现,胃内的表面活性物质具有细胞保护作用。作者等用1ml 0.6molHCl灌入结扎幽门的大鼠以造成胃粘膜损伤模型,并作了下列观察:(1)如果预先用1ml表面活性物质混悬液注入胃,30min后再注入HCl,可明显减轻HCl引起的胃粘膜坏死和出血;(2)如果在表面活性物质灌胃之前45min于皮下注射消炎痛(5mg/kg)阻断前列腺素(PG)合成,虽然能加重对照组的胃粘膜损伤,但不能阻断表面     

疏水性肺表面活性物质蛋白的结构研究进展

疏水性肺表面活性物质蛋白（ＳＰ）包括ＳＰ－Ｂ和ＳＰ－Ｃ,它们在决定肺表面活性物质的结构、代谢及功能等方面有重要作用。ＳＰ－Ｂ和ＳＰ－Ｃ功能的多样性可能与其结构的特殊性有关,在表达及合成的过程中,二的结构均经过了复杂的加工,使之能与脂质系统相互作用以发挥其生理功能。     

肺表面活性物质相关蛋白的特性研究

肺表面活性物质相关蛋白的特性研究谢尔凡（第三军医大学烧伤研究所,重庆６３００３８）关键词肺表面活性物质,表面活性物质相关蛋白肺表面活性物质是由脂质和蛋白质组成的复合物,其主要生理功能是降低肺泡表面张力,维持肺泡结构相对稳定。近年来,特异性的肺表面活性...     

生物表面活性剂——表面活性素

生物表面活性剂是由微生物在一定条件下合成的具有表面活性的物质,具有对环境无毒、生物降解性能好等特性,广泛应用于洗涤剂、化妆品、食品、医药、石油等工业领域及农业和环境保护方面。该文对表面活性素的生产、结构、性质及应用方面进行了综述。     

肺表面活性物质及其在肺感染作用中的研究进展

肺表面活性物质是位于肺泡上皮细胞表面的由关键性脂质蛋白质组成的具有多种功能的复合物。肺表面活性物质中各组成部分的联合效应是肺保持稳定性和宿主防御传染病病原体的基础。在此,就肺表面活性物质的主要成分、结构、功能及其与肺感染的关系做一简要综述。     

生物表面活性剂发酵液的组成及表面活性

假单胞菌（Pseudomonas sp.)生长在正烷烃或植物油中,能生产出表面活性物质,分析其发酵液,类脂物和多糖是主要代谢产物,发酵液中表面活性物质主要是糖脂化合物及甘油单脂,发酵液稀释到5%,能将表面张力降到27mN/m,表面性能在广泛pH(2-12),高矿化度溶液中和高温下都非常稳定,发酵液的良好表面性能显示了它在三次采油,土壤处理等领域中应用潜力。     

肺表面活性物质相关蛋白A与肺部免疫防御研究进展

肺表面活性物质相关蛋白A（SP—A）是一种高度保守的亲水性糖蛋白,属于C-型凝素家族成员,相对分子质量为29～36kDa。SP—A是肺部重要的天然免疫防御分子,在肺的局部防御和天然免疫反应中起着十分重要的作用。它不仅可调节局部免疫和炎症反应、调理吞噬作用,还可凝集病原微生物、影响趋化作用及促进杀菌作用等。     

大鼠冷暴露后肺表面活性物质的变化

大鼠冷暴露后肺表面活性物质的变化张秀琳王月燕刘改香刘明远（济南军区医学高等专科学校生理教研室,济南２５００２２）肺表面活性物质（ＰＳ）除具有降低肺泡表面张力的作用外,还在下呼吸道防御机制中起重要作用。急性冷暴露后易患呼吸系统感染及加重诱发某些呼吸系统...     

合成生物活性物质的生物安全风险和应对策略研究

生物代谢工程以微生物为载体,以生命系统各个阶段形成的代谢产物为天然模板和设计蓝图,采用合成生物技术合成活性物质。这些活性物质中部分有害或具有潜在安全威胁,如毒素和蛋白质复合物、可用于临床治疗也可危害健康的药物分子及其衍生物、国际公约限制使用的化学制剂等,可能对生物安全产生不利影响。通过对采取天然代谢通路与非天然代谢通路生物合成的活性物质、化学合成的活性物质和活性物质递送技术相关的合成生物学安全风险的梳理分析,为促进活性物质的合成生物创新发展和应用提出科学应对策略。     

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.