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1.
目的甲型H1N1流感病毒A/California/7/2009与A/California/4/2009病毒序列比较同源性在99%以上,本实验旨在比较两株病毒感染BALB/c小鼠研究感染力强弱。方法分别将A/California/7/2009(CA7)与A/California/4/2009(CA4)两株病毒分别连续10倍稀释后,对4~6周龄雌性BALB/c小鼠经乙醚麻醉后进行滴鼻攻毒,每个稀释度接种10只实验小鼠,测定CA7 MLD50为101.24/0.05 mL,检测小鼠感染、致病的多项指标,观察期为14 d。结果相同TCID50的CA7和CA4病毒感染小鼠,CA4感染小鼠后14 d内死亡率为20%,而CA7感染小鼠后8 d内死亡率为100%。CA7 106TCID50感染的小鼠病理表现为重度弥漫性间质性肺炎,CA4 106TCID50感染的小鼠病理表现为中度-重度间质性肺炎。结论在相同条件下,CA7感染力明显强于CA4。  相似文献   

2.
金粉蕨属(Onychium Kaulfuss)隶属广义凤尾蕨科中的凤尾蕨亚科。迄今为止,该属属下分组及种间界定等仍有诸多问题亟待解决。本研究选取5个叶绿体DNA 序列片段 (rbcL/atpA/matK/trnL-trnF/trnG-trnR),采用最大似然法(ML)和贝叶斯法(BI)构建金粉蕨属的系统发育树。结果表明:(1)金粉蕨属的9个成员被分置于两大支上。其中野雉尾金粉蕨(Onychium japonicum(Thunberg) Kunze)、西藏金粉蕨(O.tibeticum Ching & S.K.Wu)、木坪金粉蕨(O.moupinense Ching)、湖北金粉蕨(O.moupinense var. ipii(Ching) K.H.Shing)、栗柄金粉蕨(O.japonicum var. lucidum(D.Don) Christ)、黑足金粉蕨(O.cryptogrammoides Christ)、繁羽金粉蕨(O.plumosum Ching)聚为一支;而金粉蕨(O.siliculosum(Desvaux) C.Christensen)和蚀盖金粉蕨(O.tenuifrons Ching)则聚为另一支,可为该属的属下分组提供分子系统学证据;(2)野雉尾金粉蕨与栗柄金粉蕨在系统树中并没有聚在一起,而是被其它类群分割开来,不支持将后者作为野雉尾金粉蕨的变种,建议将栗柄金粉蕨提升为种的等级;(3)系统树上木坪金粉蕨与湖北金粉蕨的样本聚在一个细支上,支持《中国植物志》将湖北金粉蕨作为木坪金粉蕨变种的分类处理;(4)西藏金粉蕨与野雉尾金粉蕨聚在一起,并得到较高的支持,说明两者的关系近缘。  相似文献   

3.
目的甲型H1N1流感病毒A/California/7/2009感染BALB/c小鼠,研究甲型H1N1流感病毒病毒性肺炎发病机制。方法 4~6周龄雌性BALB/c小鼠60只,随机分为2组,实验组和对照组,每组30只。CA7流感病毒滴鼻制备甲流病毒感染小鼠模型。攻毒后第5天解剖实验和对照组小鼠,取肺组织,测定肺组织中IL-2,IL-6,TNF-α含量。结果结果实验组肺组织中IL-6,TNF-α,水平明显高于对照组,IL-2水平明显低于对照组,差异均有显著性(P〈0.05)。结论 IL-6、TNF-α、IL-2这3种细胞因子在感染甲流病毒后的显著性变化与病毒感染后的肺组织病理损伤有密切的关系。  相似文献   

4.
阿尔茨海默病(Alzheimer's disease,AD)是一种重要的痴呆类型,AD是一种变性痴呆,特点是65岁以上的老年人易患.AD起病侵袭,主要表现是记忆力下降,神经生化改变参与其中,许多神经递质缺陷.AD的病因至今未明.丝裂原激活的蛋白激酶(Mitogen-activated protein kinase,MAPK)和蛋白激酶C(protein kinase C,PKC)信号传导通路在细胞增殖、分化、生长、凋亡和恶性转化中起重要作用.本文综述了信号传导通路在阿尔茨海默病中的作用.  相似文献   

5.
探讨利用视网膜色素上皮 (retinalpigmentepithelium ,RPE)细胞移植介导目的基因转移至视网膜的可行性。人的RPE细胞在体外经携带绿色荧光蛋白 (greenfluorescentprotein ,GFP)基因的逆转录病毒感染及G4 1 8筛选后 ,手术显微镜直视下经睫状体平坦部注射到兔眼视网膜下间隙。术后通过活体荧光眼底照相 ,荧光显微镜、共聚焦显微镜及透射电镜等观察眼球铺片及切片 ,发现经 gfp基因修饰的人RPE细胞在兔眼视网膜下间隙可存活一年以上。移植的RPE gfp细胞不仅仅局限于移植部位 ,大多扩散到超过 2~ 3个象限的眼底 ,镶嵌于宿主RPE细胞之间或呈单层排列在宿主色素上皮与神经视网膜之间 ,并持续高水平表达GFP。移植后早期玻璃体内每周注射免疫抑制剂普乐可复 (FK5 0 6 )可明显改善移植细胞的存活状态  相似文献   

6.
李长龙  潘玉春  孟和  王子林  黄雪根 《遗传》2006,28(2):159-164
具有不同遗传特性的猪种具有不同的肉质性状。尤其是地方品种和引进品种间在肉质性状存在极大的差异。在已有的研究中H-FABP,MC4R,ADD1基因同肌内脂肪或背膘相关。利用梅山猪、苏太猪和杜×长×大猪为试验动物,研究上述3个基因的多态性分布和多态性同肌内脂肪和背膘的相关性。结果表明:3个基因的多态性分布在不同猪种间存在极显著的差异,这种差异可能是肌内脂肪(IMF)或背膘(BF)不同的主要原因之一。连锁分析表明:H-FABPADD1基因多态性同IMF有显著的相关,但是同BF没有显著的相关;MC4R基因的多态性同IMF和BF都有显著相关性。说明:H-FABPADD1基因多态性有可能应用到提高IMF,同时不影响BF的育种实践中。   相似文献   

7.
目的 探讨臭氧消融术联合射频热凝术治疗腰椎间盘突出症的临床治疗.方法 对延边大学附属医院采用射频热凝联合臭氧消融术治疗腰椎间盘突出症的56例进行分析.结果 所有患者治疗后不同时期VAS评级、MacNab标准评定;术后1周与术后24 h的VAS评级差异均有统计学意义.结论 射频热凝联合臭氧消融术治疗腰椎间盘突出症是治疗腰椎间盘突出症的一种新兴手段.  相似文献   

8.
本研究在完成FMDVO/QYYS/s/06株全基因组序列测定的基础上,分3段对全基因组进行克隆,其后将各片段克隆到载体P43中,从而获得携带O/QYYS/s/06株基因组全长cDNA的重组质粒P43C。将重组质粒P43C与表达RNA聚合酶的质粒T7共转染BHK-21细胞,48h后收获培养液接种2~3d乳鼠,取经乳鼠传代后的第4代病毒液,经反向间接血凝、中和试验和测序等方法证明拯救的病毒为O型FMDV。以上结果表明,O/QYYS/s/06株全长cDNA分子克隆的构建成功。  相似文献   

9.
卵巢癌是女性生殖系统常见的恶性肿瘤,发病率居于妇科恶性肿瘤第三位,死亡率居于妇科恶性肿瘤之首。目前对卵巢癌的标准治疗包括肿瘤细胞减灭术及卡铂和紫杉醇的联合化疗。PI3K/AKT/mTOR信号通路在卵巢癌的细胞增殖、侵袭、细胞周期进展、血管生成及耐药中发挥重要作用,是卵巢癌中最常发生改变的细胞内途径。本文对PI3K/AKT/mTOR信号通路及其在卵巢癌增殖和进展中的影响、PI3K/AKT/mTOR信号通路抑制剂在卵巢癌中的治疗应用做简要综述。  相似文献   

10.
Li HY  Yang L  Liu W  Zuo J 《生理学报》2011,63(1):69-74
本文旨在探讨促存活信号通路Raf/Mek/Erk1/2是否参与了葡萄糖调节蛋白75(glucose-regulated protein75,GRP75)对缺糖诱导的细胞凋亡的抑制作用。GRP75过表达的PC12细胞给予Raf/Mek/Erk1/2通路抑制剂U0126预处理之后,无糖培养6、12和24h,同时以DMSO预处理的GRP75过表达PC12细胞组为对照。Western blot检测Erk1/2的磷酸化和表达水平,MTT实验检测细胞存活率,Hoechst 33258染色观察凋亡细胞核的形态学改变,流式细胞仪检测细胞亚二倍体峰,免疫荧光检测细胞色素c(cytochrome c,Cytc)向胞浆的弥散情况。结果显示:U0126在没有影响Erk1/2表达水平的前提下,阻断了GRP75对Erk1/2磷酸化水平的维持;U0126处理组的凋亡率明显高于对照组;U0126处理组Cytc从线粒体向胞浆释放的时间明显早于对照组,同时Cytc向胞浆的弥散程度大于对照组。以上结果提示,U0126通过抑制Erk1/2磷酸化,阻断了缺糖状态下GRP75对Cytc释放和细胞凋亡的抑制作用,这表明GRP75是通过Raf/Mek/Er...  相似文献   

11.
钙调素对细胞周期的调节   总被引:1,自引:0,他引:1  
RC3细胞是一种用真核表达载体1~(CaM)转染NIH 3T3细胞建成的可调钙凋素(Calmodulin,CaM)高表达细胞模型。通过分子杂交及蛋白免疫印迹方法证实在地塞米松(Dexamethasome,DXM)作用下,RC3细胞可高表达CaM。CaM的过表达使G_1期细胞减少,S期细胞增加;CaM拮抗剂三氟拉嗪(trifluoperazine,TFP)则使G_1期细胞增加,S期细胞减少。高表达CaM使细胞分裂指数提高,G_2期细胞减少,有丝分裂前期细胞增加,M中期细胞比例下降。而TFP处理则使分裂指数下降,G_2期细胞增加,M前期细胞减少,M中期细胞增加。实验结果表明CaM在G_1/S、G_2/M和M中期/M后期3个位点上对细胞周期进行调控;通过加速G_1至S期,G_2至M期和M中期至M后期的进程,使细胞倍增时间缩短,促进细胞增殖。本工作表明,RC3细胞作为CaM表达可调细胞模型,是研究细胞周期调控的有力工具。  相似文献   

12.
本实验调查了武汉东湖浮游植物水华的各种成份以及水柱沉淀物内叶绿素α含量,根据碳与叶绿素α关系,给定了一回归方程,并计算出沉淀物中藻类活体相应的碳、氮、磷含量。从平均数值看,武汉东湖浮游植物水华的C,N,P含量分别为39.30,7.98及0.94(%);其干湿比为0.20,碳、氮比为5.10,碳、磷比为46.54,碳与叶绿素α之比则为133.32。 1983年东湖水柱沉淀物中浮游植物活体叶绿素α下沉量平均每天每平方米为43.8675微克(Ⅰ站)及35.5881微克(Ⅱ站)。利用东湖浮游植物水华各种成份含量及其各种比率计算出的东湖水柱沉淀物中浮游植物活体碳、氮、磷量,按顺序每天每平方米分别为2.53,0.50,0.05毫克(Ⅰ站)及2.09,0.41,0.04毫克(Ⅱ站)。  相似文献   

13.
环孢素A对人早孕期滋养细胞MMP-9与MMP-2表达的调控作用   总被引:1,自引:0,他引:1  
本研究的目的是探讨环孢素A对人早孕期滋养细胞侵袭能力及基质金属蛋白酶9与2 (matrix metalloproteinase 9 and 2,简称MMP-9与MMP-2)表达的调节作用,为治疗反复自然流产等妊娠疾患提供新的线索。侵袭试验观察CsA对人早孕期滋养细胞侵袭能力的调节作用;RT-PCR与明胶酶谱分析CsA对滋养细胞MMP-9与MMP-2 mRNA及蛋白水平表达的影响;In-cell West- ern检测CsA作用后滋养细胞ERK1/2磷酸化水平。结果发现,1.0μmol/L CsA明显增强滋养细胞侵袭能力,MEK激酶抑制剂U0126可抑制CsA对滋养细胞的促侵袭作用;1.0μmol/L CsA可诱导MMP- 9与MMP-2基因的转录与蛋白分泌;该诱导效应同样可被U0126所阻滞;1.0μmol/L CsA以时间依赖方式促进ERK1/2的磷酸化。结果表明,CsA可激活ERK1/2,通过MAPK/ERK1/2途径促进滋养细胞MMP-9与MMP-2基因的转录与蛋白分泌,从而增强滋养细胞的侵袭能力,对滋养细胞生物学功能具有良性调节作用。  相似文献   

14.
城市内河水体有机浓集物的致突变性试验研究   总被引:4,自引:0,他引:4  
吴伟  奚新伟 《生物技术》1998,8(4):32-37
采用GC/MS法对W市内河水体有机浓集物进行了鉴定,共检出有机物114种,其中主要为烷基苯、多环芳烃等。Ames和鱼类微核试验结果表明这些有机物中含有致突变性的物质,对TA-98辅株表现出明显的致突变活性,为移码型直接致突变物。研究表明该城市内河已遭受工业废水和其它污水的严重污染,且水质有特殊毒性。  相似文献   

15.
The authors have previously reported that the soluble serum form of the alpha subunit of the IL-2 receptor (sIL-2Rα), whose natural half-life is approximately 40 min, survived much longer in the circulation when bound by a specific antibody. In the present study, the authors evaluated the extent to which sIL-2Rα protected IL-2 in freshly collected serum using biochemical analyses, and a functional CTLL-2 assay. In particular, sIL-2Rα protected IL-2 from forming complexes with α2-macroglobulin and from inactivation in vitro. In addition, the authors demonstrated that the anti-IL-2Rα monoclonal antibody 7G7/B6, which does not inhibit the binding of IL-2 to its binding site on sIL-2Rα, protected IL-2 from degradation and inactivation in vivo in the presence of sIL-2Rα. Both125I-labelled and unlabelled IL-2 were injected into mice preinjected with humanized anti-Tac (hTac) or 7G7/B6 and sIL-2Rα, or sIL-2Rα alone. Using size-exclusion HPLC, ELISA, and CTLL-2 cell proliferation assays, we observed that the presence of 7G7/B6 led to formation of complexes with sIL-2Rα and increased the serum levels of IL-2 more than 3- to 40-fold those of groups receiving IL-2 alone, sIL-2Rα, or hTac. Taken as a whole, these results suggest that the complex of 7G7/B6 and sIL-2Rα not only prolongs the survival of IL-2 in vivo, but also maintains the bioactivity of IL-2. The use of antibodies against endogenous soluble receptors could increase the in vivo survival of cytokines, protect their bioactivity and thereby facilitate their clinical use in the treatment of various malignancies and AIDS.  相似文献   

16.
Recombinant human interleukin 11 (rhIL-11) is a multifunctional cytokine with immunomodulatory activity on both T cells and macrophages. The effects of rhIL-11 in a murine model of contact hypersensitivity (CHS) response have been studied. The CHS response is a T cell-mediated response directed against chemically modified self-proteins following epidermal exposure to haptens. CHS is generated in two phases. The sensitization phase involves dermal dendritic cell recognition of haptenized proteins and antigen presentation. The effector phase involves T cell recognition and activation. In mice sensitized with oxazolone, CHS was induced by secondary challenge to the right ear and measured by ear swelling 24 h later. rhIL-11 significantly suppressed CHS as measured by ear swelling and tissue myeloperoxidase activity when injected subcutaneously for 5 days from the day of sensitization or when administered only on the day before and the day of challenge, but was not effective when administered prior to or on the day of sensitization. These results indicate that subcutaneously administered rhIL-11 may modulate the effector phase of CHS. Administration of rhIL-11 as an oral gavage prior to sensitization also reduced CHS. However oral administration of rhIL-11 after sensitization had no effect. These results suggest that orally and subcutaneously administered rhIL-11 may act through different mechanisms to affect CHS.  相似文献   

17.
双歧杆菌的抗癌效应及其机制的初步研究   总被引:4,自引:1,他引:3  
双歧杆菌是一种重要的革兰氏阳性无芽胞厌氧杆菌,是人类肠道正常菌群中的优势菌种。本文观察了在改变栖生环境的情况下,双歧杆菌作为生物反应调节剂发挥抗肿瘤作用及其对单核巨噬细胞的激活作用。615小鼠在腹腔或皮下接种肝癌H22/F23后,从第1天起每隔3天腹腔或皮下两种途径注射双歧杆菌进行治疗,结果表明在瘤内注射给药时显示显著的抑瘤作用。双歧杆菌激活的腹腔渗出细胞(PEC)在形态学上表现为细胞表面积增大,细胞皱褶增多;在功能上则表现为杀瘤活性增强,激活的PEC经Winnassay证明对肿瘤生长的早期或中期有明显的抑制作用,用MTT比色法测定细胞毒进一步证实激活的PEC在体外具有直接杀瘤作用。实验结果提示双歧杆菌激活单核一巨噬细胞是其发挥抗肿瘤作用的重要机制。由于该菌为生理性细菌,对宿主无致病性,所以其较目前已在临床上广泛应用的其它非特异性生物反应调节剂如OK432、卡介苗等可能更具优越性,值得深入研究。  相似文献   

18.
Nucleobases are important compounds that constitute nucleosides and nucleic acids. Although it has long been suggested that specific transporters are involved in their intestinal absorption and uptake in other tissues, none of their molecular entities have been identified in mammals to date. Here we describe identification of rat Slc23a4 as the first sodium-dependent nucleobase transporter (rSNBT1). The mRNA of rSNBT1 was expressed highly and only in the small intestine. When transiently expressed in HEK293 cells, rSNBT1 could transport uracil most efficiently. The transport of uracil mediated by rSNBT1 was sodium-dependent and saturable with a Michaelis constant of 21.2 μm. Thymine, guanine, hypoxanthine, and xanthine were also transported, but adenine was not. It was also suggested by studies of the inhibitory effect on rSNBT1-mediated uracil transport that several nucleobase analogs such as 5-fluorouracil are recognized by rSNBT1, but cytosine and nucleosides are not or only poorly recognized. Furthermore, rSNBT1 fused with green fluorescent protein was mainly localized at the apical membrane, when stably expressed in polarized Madin-Darby canine kidney II cells. These characteristics of rSNBT1 were almost fully in agreement with those of the carrier-mediated transport system involved in intestinal uracil uptake. Therefore, it is likely that rSNBT1 is its molecular entity or at least in part responsible for that. It was also found that the gene orthologous to the rSNBT1 gene is genetically defective in humans. This may have a biological and evolutional meaning in the transport and metabolism of nucleobases. The present study provides novel insights into the specific transport and metabolism of nucleobases and their analogs for therapeutic use.  相似文献   

19.
天然紫杉烷类二萜化合物的核磁共振氢谱规律   总被引:7,自引:0,他引:7  
紫极醇是一种结构新颖、抗肿瘤作用机理独特的新型抗肿瘤药,已成为当前全世界研究的热点。  相似文献   

20.
互叶白千层油化学成分的研究   总被引:4,自引:0,他引:4  
贾芬  黄宇翔  丁舒敏  李青   《广西植物》1995,15(4):368-370
采用水蒸汽蒸馏收集互叶白千层芳香油,对该油进行GC/MS/DS定性分析及其总离于流图的面积归一化定量分析,鉴定出25种化合物,其中含氧化合物6种,碳氢化合物19种。直接影响该油商品价值的化学成分4-萜品醇含量约为17%,桧樟脑含量约为2.4%。  相似文献   

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