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1.
石汉平  缪明永 《生理学报》1997,49(2):173-177
本文观察了失血性休克条件下大鼠白细胞介素1(IL-1)与内毒素的关系。结果表明:失血性休克早期血浆IL-1及ET均明显升高,前者升高在先;无菌大鼠失血性休克后IL-1活性也升高,但ET无明显变化;预先给大鼠口服乳果糖以清洁肠道,或静注内毒素抗体,休克后血浆IL-1活性仍然明显升高,而血浆ET无明显升高;大鼠失血后1h将失血回输再灌注后5d血浆IL-1与ET呈平行性变化,乳果糖或抗内毒素抗体治疗后,  相似文献   

2.
双歧杆菌对失血后肠源性感染的预防作用   总被引:2,自引:0,他引:2  
本文观察双歧杆菌对失血后肠源性感染的预防作用,将大鼠分为假处理、失血、双歧杆菌+失血,新霉素+失血4组。后两组实验前分别灌注双歧杆菌或新霉素,假处理动物麻醉插管不放血,后3组动物放血2o%,6h后每组10只动物活杀取样。发现:失血组大鼠10h存活率降低,血浆ET、IL—1升高,细菌培养阳性标本增多,小肠杆/球菌比值增大,与假处理组相比差异显著。双歧杆菌治疗组大鼠时间存活率增加,血浆ET、IL—1无明显升高,细菌培养阳性标本减少,杆/球菌比例正常,与失血组相比差异显著。新霉素治疗组上述各项指标与失血组相比无显著改善。提示双歧杆菌能有效地预防失血后肠源性感染。  相似文献   

3.
研究观察失血性休克复合内毒素血症时血和组织髓过氧化物酶的变化规律。将雄性wistar大白鼠随机分为对照组、缺血组、缺血再灌流组和缺血再灌流复合内毒素组。用改良的髓过氧化物酶 (MPO)测定方法 ,测定血、肺和小肠组织MPO及相关指标的变化。结果显示肺组织MPO活性从失血性休克末开始升高 ,致内毒素血症时出现峰值 ;小肠组织MPO的活性在失血再灌流后显著升高 ,但在失血性休克复合内毒素血症后显著降低 ;血MPO活性于失血性休克和失血再灌流后均无显著性变化 ,复合内毒素后显著降低。结果表明失血再灌流后肺组织PMN扣留、聚集显著增加 ,内毒素血症促进PMN在肺中的扣留 ,这些变化与PMN上CD11b和CD18表达上调有关 ,提示失血再灌注复合内毒素时组织细胞损伤与PMN的粘附、扣留、激活有关。  相似文献   

4.
内皮素-1 mRNA反义寡核苷酸预防大鼠急性缺血性心律失常   总被引:3,自引:1,他引:2  
Lin L  Yuan WJ  Chu XL  Xu H  Li L  Ren AJ 《生理学报》1999,51(5):533-540
本实验夹闭雄性SD大鼠冠状动脉左前降支(LAD)造成急性心肌缺血,观察LAD闭塞后1h内缺血性心律失常的发生。在LAD夹闭前2h,静脉注射本室设计的人内皮素-1mRNA反义寡核苷酸(AS-ODN)以阻断ET-1mRNA表达,观察AS-ODN对血浆ET-1浓度和急性缺血性心律失常的影响。  相似文献   

5.
本实验从体内、体外两个方面初步探讨β内啡肽(βEP)刺激IL1释放的机制。给正常大鼠静注不同浓度的βEP,血浆IL1活性显著升高,呈剂量效应关系;给正常大鼠静注βEP及LPS,血浆IL1活性显著高于二者的单独作用;将不同浓度的βEP与巨噬细胞一起培养(不加LPS),培养液中呈现IL1活性,并在一定范围内与βEP浓度有剂量效应关系;以低浓度的βEP与巨噬细胞孵育1h后去除βEP,再加入LPS,发现βEP预处理组上清液IL1活性显著高于未加βEP的对照组。结果提示:βEP既能直接刺激巨噬细胞产生IL1,又能提高巨噬细胞对IL1诱生物LPS的敏感性。  相似文献   

6.
利用大鼠颅骨开窗观察软脑膜微循环的方法研究了内皮素(ET-1)10-10-10-7mol/L对软脑膜微循环的影响以及失血性休克时软脑膜对ET-1的反应性。并用10-7mol/L造成失血性休克后脑血管痉挛的模型,观察尼莫地平、川芎嗪、654-2对内皮素引起血管痉挛的治疗作用。10-9、10-8和10-7mol/L3种浓度ET-1可使软脑膜小动脉、细动脉强烈收缩,收缩率分别为27.7%、46.8%、78.5%,其收缩强度与ET-1的浓度有关。对静脉的作用不明显。10-10mol/LET-1可使细动脉轻度扩张。出血性休克时,软脑膜血流明显减慢,小动脉、细动脉管径对ET-1的收缩作用更敏感,脑组织血流明显减少。尼莫地平具有较好的拮抗ET-1引起软脑膜动脉的收缩和改善局部微循环的作用。川芎嗪也能拮抗ET-1引起软脑膜动脉的收缩,但作用较尼莫地平弱。654-2不能缓解ET-1对软脑膜动脉的收缩作用。  相似文献   

7.
利用大鼠颅骨开窗观察软脑膜微循环的方法研究了内皮素(ET-1)10^-10-10^-7mol/L对软脑膜微循环的影响以及失血性体克时软脑膜对ET-1的反应性。并用10^-7mol/L造成失血性休克后脑血管痉挛的模型,观察尼莫地平、川芎嗪、654-2对内皮素引起血管痉挛的治疗作用。10^-9,10^-8和10^-7mol/L3种浓度ET-1可使脑膜小动脉、细动脉强烈收缩,收缩率分别为27.7%、46  相似文献   

8.
雄性SD大鼠33只,体重180—250g,随机分成四组。正常对照组6只;哌唑嗪组8只,于实验第1、2、3日上午用哌唑嗪灌胃(1mg/kg体重)共3次,第2日下午腹腔注射半乳糖胺(600mg/kg体重)1次,第4日上午处死动物,取肝脏及血清作有关检查;普萘洛尔组及N.S对照组分别用普萘洛尔(2mg/kg体重)及N.S(10ml/kg体重)代替哌唑嗪灌胃,处理程序同哌唑嗪组。结果表明:一、哌唑嗪能显著减轻肝脏病变及血清ALT的升高。二、哌唑嗪对肝损害后肝组织SDH、Mg2+-AT-Pase、ChE、ACP、CCo等酶活性的恢复有显著效果。三、哌唑嗪组LPO明显低于N.S对照组(P<0.01)而SOD活性明显高于N.S对照组(P<0.01)。普萘洛尔组各项指标同对照组比较均无显著差异(P>0.05)。提示:哌唑嗪对大鼠实验性肝损害有一定的保护作用。  相似文献   

9.
两个品种的大豆叶圆片经10-4mol/L和10-3mol/L的H2O2处理12h后,超氧物歧化酶(SOD)、过氧化氢酶(CAT)与谷胱甘肽还原酶(GR)活性明显增加,但10-2mol/L的H2O2处理却使这些酶活性降低。抗旱性较强的大豆品种小粒豆1号较抗旱性较弱的鲁豆4号能维持较高的叶绿素含量和较高的SOD、CAT及GR活性,对H2O2的抗性较强。50μmol/L的亚胺环已酮(CHM)能消除H2O2对SOD、CAT与GR活性的刺激作用,而同样浓度的放线菌素D(AMD)则不能。  相似文献   

10.
研究了超氧化物歧化酶(SOD)对创伤小鼠淋巴细胞膜流动性及功能的影响。结果显示,SOD体内应用(10000U/kgd,伤后0-3d)可明显降低创伤小鼠血清、脾脏、胸腺、肠系膜淋巴结组织及T细胞中丙二醛(MDA)含量,提高淋巴细胞膜及T细胞质膜、线粒体膜、微粒体膜的流动性,对创伤后T细胞转化活性降低、白细胞介素2(IL-2)生成减少、IL-2受体(IL-2R)表达受抑、IL-2介导的淋巴细胞增殖反应(IL-2MLPR)降低均具有不同程度的恢复作用。表明SOD可保护创伤后淋巴细胞免受氧自由基的损害,并提高淋巴细胞的功能。  相似文献   

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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.  相似文献   

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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.  相似文献   

17.
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.  相似文献   

18.
肝癌中HBV和HCV基因和抗原的分布及意义   总被引:1,自引:0,他引:1  
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  相似文献   

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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.  相似文献   

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