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1.
p38 MAPK参与LPS诱导RAW细胞TNF—α基因表达的调控   总被引:3,自引:0,他引:3  
构建TNF-α启动子驱动的荧光酶报告基因系统,研究p38MAPK信号转导系统对TNF-α基因表达的影响,RAW264.7细胞共转染实验发现,LPS对p38的激活作用与其诱导TNF-α转录活性的作用显著相关,虽然单纯转染p38未见明显诱导TNF-α报告基因系统的转录活性。  相似文献   

2.
双歧杆菌及其表面分子的免疫增强作用   总被引:23,自引:6,他引:17  
研究双歧杆菌及其脂磷壁酸、细胞壁肽聚糖、培养乏液对小鼠腹腔渗出细胞、脾细胞IL-1、IL-2、IL-6、TNF、IFN-γ活性和脾NK、LAK细胞活性的影响。结果发现双歧杆菌全菌、脂磷壁酸、肽聚糖多次注入小鼠腹腔一段时间后,小鼠脾NK细胞、LAK细胞活性和IFN-γ活性增强,腹腔渗出细胞产生IL-1、IL-6、TNF活性增强,其中以脂磷壁酸作用最强,肽聚糖次之,培养乏液也有一定作用。双歧杆菌及其表面分子对小鼠脾细胞、腹腔渗出细胞IL-2活性无显著影响。双歧杆菌的免疫增强作用在抗感染、抗肿瘤机理中占有十分重要的地位。  相似文献   

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以25μg/ml的丝裂霉素C处理巨噬细胞30min,可阻断巨噬细胞白介素1(IL-1)、白介素6(IL-6)、肿瘤坏死因子(TNF)及前列腺素E2(PGE2)的合成与分泌。创伤小鼠巨噬细胞经丝裂霉素C处理后,可明显抑制正常T细胞白介素2(IL-2)mRNA及IL-2受体(IL-2R)α mRNA水平,并增强Ts细胞的抑制活性。去除T细胞中Ts细胞可使巨噬细胞的抑制作用消失。表明创伤后巨噬细胞可通过  相似文献   

4.
本实验应用加热处死的青春双歧杆菌DM8504菌株皮下注射荷瘤HCa-F25/16A3-F肿瘤的BALB/c小鼠,酶联法测定小鼠体内TNF-α、IL-6的含量,TUNEL法及电镜观察肿瘤组织中是否有凋亡细胞的存在。实验结果指出:双歧杆菌能提高荷瘤小鼠体内TNF-2的含量,较对照组明显升高,但IL-6的含量处理组与对照组之间无显著性差异。TUNEL法除观察到不同程度的坏死组织外,未见到散在凋亡的肿瘤细  相似文献   

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本实验应用加热处死的青春双歧杆菌DM8504菌株皮下注射荷瘤HCa-F25/16A3-F肿瘤的BALB/c小鼠,酶联法测定小鼠体内TNF-α、IL-6的含量,TUNEL法及电镜观察肿瘤组织中是否有凋亡细胞的存在。实验结果指出:双歧杆菌能提高荷瘤小鼠体内TNF-2的含量,较对照组明显升高,但IL-6的含量处理组与对照组之间无显著性差异。TUNEL法除观察到不同程度的坏死组织外,未见到散在的凋亡的肿瘤细胞,电镜观察与TUNEL结果相一致,肿瘤细胞呈现坏死细胞的超微结构,未见凋亡细胞所具有的典型的形态特征。结果提示:双歧杆菌通过调节机体的免疫系统发挥抗肿瘤的作用,其对HCa-F25/16A3-F肿瘤细胞的杀伤是通过坏死的方式实现的。  相似文献   

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在应用双歧杆菌活菌制剂治疗慢乙肝期间,重点观察了T细胞亚群(CD3,CD4,CD8)、NK细胞(CD(16))、白细胞介素Ⅱ(IL-2)分泌细胞、肿瘤坏死因子(TNF)等细胞免疫指标治疗前后的动态变化,同时观察了病人血内毒素水平的动态变化和乙肝病毒标志物(HBVM)的改变。结果表明:(1)与对照组比较,双歧杆菌活菌制剂可使慢乙肝病人CD3+,CD4+数目明显增多,而对CD8+细胞数目无明显影响;(2)双歧杆菌活菌制剂可使CAH组的CD16+细胞显著增多(p<0.05);使CAH组和CPH组的IL-2分泌细胞均有非常显著和显著增加(分别p<0.01和p<0.05);(3)CAH组病人血中内毒素和TNF水平在双歧杆菌活菌制剂治疗后,匀出现非常显著降低(p<0.01);CPH组TNF水平较对照组无显著变化,但内毒素水平较对照组显著降低(p<0.05);(4)满疗程后(60天)CAH组有6例,CPH组有5例HBeAg阴转(分别为26.06%和25.0%),而对照组仅2例阴转(13.33%),两治疗组与对照组比较有显著性差异(p<0.05)。  相似文献   

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通过RNA印迹分析和亚硝酸盐含量测定检查TNF-α、IL-1β和LPS对大鼠血管平滑肌细胞(VSMC)诱导型一氧化氮合酶(iNOS)基因表达及NO生成的影响.结果表明,TNF-α、IL-1β和LPS均能显著诱导VSMCiNOS基因表达和促进NO生成,其作用强度与浓度和作用时间有关;双因素(TNF-α+LPS,LPS+IL-1β)对诱导iNOS基因表达及NO生成产生协同作用.PolymyxinB和地塞米松可部分抑制TNF-α对iNOS基因表达的诱导作用及NO生成  相似文献   

8.
耐氧双歧杆菌及其B-CW对荷瘤鼠TNF-α的体内诱导   总被引:4,自引:3,他引:4  
本文采用放射免疫方法(RIA),检测荷S180肿瘤小鼠外周血中TNF-α的含量,观察双歧杆菌(Bifidobacterium)及其细菌壁(CelWalsofBifidobacterium,B-CW)的免疫调节作用,探讨其抗肿瘤机制。结果表明该菌及其B-CW均可明显地促进机体产生TNF-α,发挥抗肿瘤作用  相似文献   

9.
地塞米松(Dex)、噻庚啶(Cyp) 和山莨菪碱(Ani) 对脂多糖(LPS) 诱导的大鼠肝脏TNFα表达的影响。Wistar大鼠40 只, 静脉注射LPS(EcoliO111B4 5m g/kg) 后, 立即静脉给予Dex 5m g/kg、Cyp5m g/kg 或Am i10m g/kg,于LPS攻击后2h 取动物的肝脏,APAAP法进行TNFα免疫组织化学研究,North-ern 杂交分析TNFαm RNA 表达水平。结果发现LPS攻击后2h, 肝脏TNFαm RNA 表达水平显著增高, 肝脏枯否氏细胞胞浆内有大量的TNFα红染颗粒。Dex、Cyp 或Ani均能显著降低大鼠肝脏TNFαm RNA 水平和TNFα含量。结果表明Dex、Cyp 和Ani均显著抑制LPS诱导的TNFα基因表达, 可能有抗感染性休克作用。  相似文献   

10.
大球母贝精子介导外源基因转移研究   总被引:9,自引:0,他引:9  
将大球母贝(Pinctada maxima Jameson)精子与“全鱼”GH基因重组体pCAgcGH和pCAgcGHc的线性DNA混合,温育30min,经6次、2^7、10kV脉冲电处理后,与卵子受精,得到若干贝苗。从贝苗中提取DNA,经PCR扩增和Southern blot分子杂交表明,部分受体带有外源基因,当与精子温育的外源基因浓度分别为2μg/mL,6μg/mL及18μg/mL时,相应贝苗  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   

18.
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   

19.
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   

20.
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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