氦氖激光对大鼠心肌超微结构、SOD和MDA影响的观察

为了解低强度氦氖激光对心肌细胞超微结构、超氧化物歧化酶（SOD）和丙二醛（MDA）的影响,采用2．87J／cm^2,7.17J/cm^2和28.66J/cm^2三种剂量氦氖激光照射大鼠心前区,电镜观察心肌超微结构,测定心肌组织SOD和MDA的含量。结果发现心肌线粒体有轻微损伤,心肌组织SOD含量在7．17J／cm^2剂量显著下降（P＜0．05）,而在28．66J／cm^2剂量显著升高（P＜0．05）,心肌组织MDA含量在7．17J／cm^2和28．66J／cm^2两种剂量下降有显著升高（P＜0．01）,在2．87J／cm^2剂量,心肌组织SOD和MDA含量均无显著变化（P＜0．05）。结果提示心肌SOD含量和脂质过氧化随不同的激光剂量而变化。     

低能量激光照射对小鼠脾脏NK细胞活性影响的试验研究

目的：研究能量激光照射对小鼠NK细胞活性的影响,以便从NK细胞活性的角度阐明其免疫调节效应。方法：以BALB／c小鼠为研究对象,应用7.337J/cm^2,11．00J/cm^2,14．67J/cm^2,22．00J/cm^2和36．67J/cm^2五种剂量的氦氖激光作小鼠内眼角照射,连续照射8d,并于照射开始后第3d,6d,9d,13d和第17d,动脉监测实验鼠脾脏NK细胞活性。结果：以日剂量为7.33J/cm^2,11.00J/cm^2,14.67J/cm^2和22.00J/cm^2LELI照射小鼠四个剂量组均可增强NL细胞的活性（P＜0．01或P＜0．05）,但其峰值的出现随着LELI剂量的增大而加快,22．00J/cm^2剂量组在第3d就达到峰值,而其余三组则分别在第9d或第13d时达到峰值,与相相反,大剂量36.6J/cm^2ELEI组NK活性则表现出明显的抑制效应。结论：适当剂量的低能量激光照射剂可对小鼠脾脏NK细胞活性产生增强效应,而过大剂是LELI则产生抑制效应。     

盐生隐杆藻胞外多糖(EPAH)抗衰老的实验研究

通过检测实验小鼠血清中的SOD、CAT、MDA、GSH的活性,同时检测肝、脑中脂褐素(Lf)的量以及胸腺系数和脾系数等多项指标,研究了盐生隐杆藻胞外多糖抗衰老活性,并通过耐力实验研究了盐生隐杆藻胞外多糖对小鼠增强耐力的作用.结果显示EPAH能明显降低老龄小鼠肝、脑脂褐素的含量,降低老龄小鼠血清中MDA的含量,增强老龄小鼠血浆中SOD、GSH、CAT的生物学活性,同时增强抗应激能力,提示EPAH有提高小鼠抗衰老的作用.     

镉长期暴露对黑斑蛙的氧化胁迫和抗氧化能力的影响

在实验条件下,将黑斑蛙暴露于12．5mg／L和25．0mg／L浓度的镉溶液中30d,分别测定了黑斑蛙在暴露10、20和30d时肝、肾组织中镉（Cd）含量、过氧化产物丙二醛（MDA）的含量、还原型谷胱甘肽（GSH）含量和超氧化物歧化酶（SOD）活性,以探讨镉对机体的脂质过氧化作用及机体的抗氧化损伤机制。实验结果表明,不同剂量组黑斑蛙肝、肾镉含量、MDA含量均随着镉暴露时间的延长而升高,且肝MDA含量与镉在肝中的蓄积量呈显著正相关（R^2=0．8643,n=9）。肝脏GSH含量随镉暴露时间的延长而被显著诱导,且与MDA含量呈显著正相关（R^2=0．5933,n=9）;肾GSH含量则随暴露时间的延长而显著下降,与MDA含量呈显著负相关（R^2=0．8609,n=9）。不同剂量组肝SOD活性随镉暴露时间的延长而升高,肾SOD活性在高剂量组随镉暴露时间的延长表现为先升高后回落下降的趋势。可见,在镉的长期暴露下,细胞膜过氧化增强是镉伤害机体的主要原因,而GSH含量、SOD活性的升高则可能是机体抗过氧化的机理之一。     

蜂胶黄酮对小鼠脑so D 、 GsH 一Px 、 MDA 的影响

目的：研究蜂胶黄酮对小鼠脑组织的抗氧化系统的作用,以期探讨蜂胶黄酮的抗衰老作用机制。方法：以小鼠为实验对象,以其脑SOD、GSH—Px、MDA为指标,考察蜂胶黄酮的抗衰老作用。结果：蜂胶乙醇提取物（EEP）可使脑组织中SOD、GSH—Px活性明显增高,和空白组相比具有显著差异（P〈0、01）;使脑组织MDA明显降低,和空白组相比具有显著差异（P〈0．01）。结论：EEP可有效地提高脑组织中抗氧化酶的活性,降低脑MBA的含量,抑制和／或减轻脂质过氧化反应,从而防止了自由基过氧化对脑组织的损伤,可能是有效的脑组织保护荆。     

大豆卵磷脂对小鼠的抗疲劳和抗氧化作用研究

目的：研究大豆卵磷脂的抗疲劳及抗氧化作用。方法：小鼠经口给予大豆卵磷脂30天后,采用负重游泳实验,观察记录小鼠游泳死亡时间;检测血清尿素氮、肝糖原;测定血清和肝匀浆超氧化物歧化酶（SOD）活性、谷胱甘肽过氧化物酶（GSH—Px）活力、丙二醛（MDA）含量。结果：给予大豆卵磷脂后,与对照组相比,实验组小鼠负重游泳时间明显延长,肝糖原消耗量减少,降低运动后血清尿素氮水平（P〈0．05）;升高小鼠血清和肝匀浆SOD活性及GSH-Px活力,降低MDA的含量（P〈0．05）。结论：大豆卵磷脂具有抗疲劳和抗氧化作用。     

辐射所致小鼠肾脏氧化损伤及川芎嗪的保护作用

目的:研究川芎嗪对辐射所致小鼠肾脏氧化损伤的预防和治疗作用。方法:采用60Co-γ射线5 Gy全身单次照射小鼠造模,在照射前和照射后分别于每天腹腔注射川芎嗪130 mg/kg,连续给药10 d,进行预防和治疗,并设对照组,观察肾组织中丙二醛(MDA)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、还原型谷胱甘肽(GSH)、谷胱甘肽过氧化物酶(GSH-Px)及总抗氧化力(T-AOC)的变化。结果:与阴性对照组比较,照射可显著增加肾组织中MDA的含量(P<0.05),降低SOD、CAT的活性(P<0.05),升高GSH-Px活性(P<0.05),降低GSH含量(P<0.05),使肾组织T-AOC下降(P<0.05),。与照射组比较,给予川芎嗪预防和治疗后,均可降低肾组织MDA含量(P<0.05),升高肾组织T-AOC(P<0.05),且治疗组优于预防组,与阴性对照组无显著性差异。同时,预防组可使SOD活性和GSH含量升高(P<0.05),治疗组可使SOD和CAT活性增高(P<0.05),但均对GSH-Px活性无显著影响(P>0.05)。结论:川芎嗪具有很好的抗氧化作用,无论预防和治疗均可降低辐射所致小鼠肾脏的氧化应激损伤,并且治疗效果优于预防效果。     

脉冲Nd:YAG激光对单层KB细胞损伤效应的研究

目的：观察脉冲Nd：YAG激光照射体外单层培养KB细胞后的形态改变及损伤后HSP70,c-Fos的表达情况,初步探讨较强脉冲激光对细胞的损伤效应及损伤修复机制。方法：建立单层培养细胞的脉冲Nd：YAG激光损伤模型,每个脉冲能量密度为160J／cm^2～186J／cm^2或220J／cm^2～257J／cm^2,分别于照后即刻、2h和6h,用台盼蓝染色、TUNEL检测分析该激光对KB细胞的损伤特点,免疫组化法检测HSP70,c-Fos的表达水平。结果：当照射剂量为220J／ecm^2～257J／cm^2时,照后即刻,光斑中央细胞形态严重破坏,直接坏死;周围细胞形态未发生明显改变。2h后周围细胞TUNEL。着色也增强,呈强阳性。照后6h光斑中央及周围细胞着色均减弱。TUNEL着色区直径随时间先扩大后缩小。当照射剂量为160J／cm^2～186J／cm^2时,细胞内HSP70、c-Fos表达随时问先显著增强,而后减弱至正常。结论：脉冲Nd：YAG激光在所选剂量下,可以引起单层KB细胞的损伤,包括即刻坏死、延迟性死亡及可逆性损伤。HSP70、c-Fos的高表达说明它们在保护受损细胞、修复激光所致损伤中发挥重要作用。     

低强度HeNe激光辐照人体外周血对淋巴细胞染色体影响的研究

本文通过低强度Ｈｅ－Ｎｅ激光以能量密度分别为１４．３１Ｊ／ｃｍ＾２（辐照５’）、２８．６２Ｊ／ｃｍ＾２（辐照１０）、５７．２４Ｊ／ｃｍ＾２（辐照２０）１１４．５２Ｊ／ｃｍ＾２（辐照４０）燠夫体外周血后,检测其淋染色畸变率（ＣＡ）,激光照射血样（能量密度由低到高）未照射血样ＣＡ分别平均为４．２９‰、３．９６‰、３．８１‰、３．５９０‰、４．１９‰、Ｘ＾检测无显著差异,说明低强度的Ｈｅ－Ｎｅ激光辐照人     

蝮蛇粉不同配伍方对老龄小鼠体内抗氧化的影响

目的研究蝮蛇粉不同配伍方对老龄小鼠体内抗氧化酶活性的影响。方法将10月龄ICR雄性小鼠按4%溶血液中丙二醛(MDA)水平随机分为蝮蛇粉(78mg/kg)组、蝮蛇粉+姜黄提取物(52+15.6mg/kg)组、蝮蛇粉+姜黄提取物+茶多酚(52+15.6+65mg/kg)组、阴性对照组,每组10只。各组灌胃给予相应药物,阴性对照组给予相应溶剂,每天1次,连续给药30天。采用试剂盒法检测4%溶血液中MDA水平、全血中谷胱甘肽(GSH)含量、血清中总抗氧化能力(T-AOC)和蛋白质羰基含量以及超氧化物歧化酶(SOD)的活力变化。结果与阴性对照组比较,其余各组小鼠4%溶血液中MDA水平显著降低,全血中GSH含量增加,血清蛋白质羰基含量明显降低、T-AOC含量和SOD活力显著提升(P0.05,P0.01);与蝮蛇粉组比较,蝮蛇粉+姜黄提取物组小鼠4%溶血液中MDA水平显著降低,全血中GSH含量增加,血清蛋白质羰基含量明显降低、T-AOC含量和SOD活力显著提升(P0.05,P0.01);与蝮蛇粉+姜黄提取物+茶多酚组比较,蝮蛇粉+姜黄提取物组小鼠各指标变化无明显差异。结论蝮蛇粉与姜黄提取物合用可有效改善老龄小鼠体内抗氧化能力,可起到延缓衰老作用。     

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.