143 resultados para 364.22[82]


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 目的 探讨大蹼铃蟾抗菌肽22 (Maximin22) 对膀胱癌 细胞株HLA2DR 及HLA2ABC 表达的影响, 并与TNF2α、 IFN2α进行比较。方法 采用肿瘤细胞培养方法,流式细胞 仪检测各实验样品对膀胱癌细胞株T24 、BIU287 、SCaBER 的HLA2DR 及HLA2ABC 表达的影响。结果 Maximin22 对 不同的膀胱癌细胞株在小剂量下即有抑制作用,并呈剂量相 关性,各实验样品未见对各膀胱癌细胞株的HLA2DR 表达 有影响,Maximin22 、TNF2α对HLA2ABC 的表达均无影响; IFN2α则对HLA2ABC 的表达有上调作用。结论 Maximin2 2 、TNF2α抗癌机制与提高肿瘤细胞HLA2DR、ABC 的表达无 关, IFN2α可通过提高肿瘤细胞HLA2ABC 的表达提高T 细 胞对膀胱肿瘤的识别杀伤能力。

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Although spermatozoa from several species of nonhuman primates have been cryopreserved, there has been no report of success with rhesus macaque spermatozoa as judged by functional assays. Two Tris-egg yolk freezing media. TEST and TTE. which have: been successfully used for cynomolgus macaque (Macaca fascicularis) spermatozoa, were compared for cryopreservation of spermatozoa From four rhesus macaques (Macaca mulatta). The postthaw motility (percentage and duration) of spermatozoa cryopreserved in TTE was much higher than that for spermatozoa cryopreserved in TEST. The function of sperm cryopreserved in TTE was evaluated by in vitro fertilization or oocytes collected from gonadotropin-stimulated prepubertal rhesus macaques. Of the inseminated oocytes. 82 +/- 13% were fertilized and 63 +/- 22 and 39 +/- 21% of the resulting zygotes developed into morulae and blastocysts. respectively. These results indicate that rhesus macaque spermatozoa can be effectively cryopreserved in TTE medium. This finding will facilitate the application of in vivo and in vitro assisted reproductive technologies in this species. (C) 2001 Academic Press.

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A novel trypsin inhibitor termed BATI was purified to homogeneity from the skin extracts of toad Bufo andrewsi by successive ion-exchange, gel-filtration and reverse-phase chromatography. BATI is basic single chain glycoprotein, with apparent molecular weight of 22 kDa in SDS-PAGE. BATI is a thermal stable competitive inhibitor and effectively inhibits trypsin's catalytic activity on peptide substrate with the inhibitor constant (K-i) value of 14 nM and shows no inhibitory effect on chymotrypsin, thrombin and elastase. The N-terminal sequence of BATI is EKDSITD, which shows no similarity with other known trypsin inhibitors. (c) 2005 Elsevier Ltd. All rights reserved.

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 目的 观察单核细胞、NK细胞和T 细胞在猪2猕猴延迟性异种移植排斥反应(DXR) 中的作用。方法 建立湖北白猪2云南猕猴的腹腔异位心脏移植模型,实验分为2 组:对照组( n = 5) ,不使用中华眼睛蛇毒因( Y2CVF) ;实验组( n = 4) 应用Y2CVF 完全清除受者体内补体。2 组受 体猴均采用环孢素A(CsA) ,环磷酰胺(CTX) 和甲基强的松龙(MP) 三联免疫抑制治疗。免疫组织 化学方法检测移植心组织中细胞间黏附分子( ICAM)21 、肿瘤坏死因子( TNF)2α、单核细胞、NK 细 胞和T 细胞的表达。结果 对照组3 个移植心在15~60 min 内发生超急性排斥反应(HAR) ,另2 个分别存活22 h 及6 d ,移植心均未见明显的炎性细胞浸润及ICAM21 和TNF2α的表达。实验组 移植心存活时间分别为8 、10 、13 和13 d ,移植物浸润细胞中可见大量的单核细胞(50 %) ,少量的 NK细胞(8 %~10 %) ,CD4 + T 细胞(15 %) 和CD8 + T 细胞(25 %) 。移植物血管内皮细胞表面出现 ICAM21 的表达上调,移植物间质中出现TNF2α的表达增加。结论 单核细胞、NK细胞和T 细胞 介导的移植物损伤,在应用Y2CVF 处理的猪2猕猴DXR 发生中发挥重要作用 

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下载PDF阅读器2008年3月-2009年3月,把35 000尾滇池金线鲃(Sinocyclocheilus grahami)仔稚鱼分别饲养于3个池塘进行对比饲养研究.密度分别是:P1为208尾/m3;P2为167尾/m3;P3为41尾/m3.饲养期间采用相同的管理措施.每天数据收集采用:在仔鱼孵化后的5~16d的每天8:00和18:00从每个育苗池中捞取5~8尾仔鱼进行测量分析.仔鱼开口30d后,每月从培育池各捞取15尾,测量全长和体重.研究发现,滇池金线鲃仔鱼的开口时间为孵化后的5 d,混合营养期3~5d,这与初孵的演池金线鲃仔鱼的全长和卵黄囊较大有关.在容易造成仔鱼大量死亡的混合营养期,通过采用浆状物-轮虫-人工混合饲料的方式,大幅度提高了滇池金线鲃仔稚鱼的存活率,孵化一年后的滇池会线鲃稚鱼存活率可达82.7%.经过一周年的饲养,滇池金线鲃稚鱼的体重由(0.027±0.01)g(0.003~1.22)增长到(8.83±0.54)g (3.7~16.7),月均增重为0.73 g;全长由(15.8±0.30)mm (11.5~20.0)增长到(91.6±1.67)mm (75.0~16.0),全长月均增长6.32 mm.滇池金线鲃稚鱼全年全长的增长呈线性相关,y=9.82+7.05month(R2=0.9891);全年体重的增长呈指数关系,y=0.0158month2.54(R2=0.9939).

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探讨蛇毒因子(CW)消耗补体对大鼠同种心脏移植急性排斥反应的影响。方法建立Wistar至sD大 鼠同种异位心脏移植模型,实验组经静脉注射CVF以消耗受体血清中补体,观察移植心存活时间,并从实验组和对照组中分别 抽取5只大鼠于术后1、3、5、6、7 d定时活杀,对比观察移植心急性排斥反应程度,血清补体活性以及CIM+、CD8+T细胞浸润程 度。结果使用CVF的实验组,其移植一fi,存活时间显著延长,平均达(32.39±23.82)d,部分移植心甚至达到长期存活,而对照 组为(6.60±0.65)d(P<0.01),病理检查及免疫组化证实实验组急性排斥反应程度、组织内C3沉积情况和CD4+、CD8+T细胞 浸润程度均较同期对照组明显减轻。结论CVF清除补体可抑制大鼠同种心脏移植急性排斥反应,显著延长移植心存活 时间。

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田间释放烟蚜茧蜂能很好地抑制烟蚜种群数量的增长。以常规施药烟田、不施药烟田作对照 ,在前期其对烟蚜的相对防效分别为 8.4%和 5 2 .8% ,中期为 6 4.0 %~ 79.0 %和 6 8.6 %~ 82 .3% ,后期为 93.0 %和 93.5 %。放蜂田烟蚜茧蜂成虫喜欢在烟株中下部叶片活动 ,1 3∶0 0~ 1 4∶0 0是其在烟株中下部活动的高峰期。烟蚜茧蜂对烟株下部叶片上烟蚜的较强选择性与烟蚜密度无关 ,下部叶片上的僵蚜数量均显著高于中、上和顶部。 1 3∶0 0~ 1 4∶0 0利用生物农药对烟株上部叶片上的烟蚜进行防治 ,既是烟蚜茧蜂与生物农药集成组装的切合点 ,又是保护利用田间烟蚜茧蜂的有效措施。

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:细胞核的起源是真核细胞进化形成的关键。回顾了过去几十年国内外对细胞核起源问题的探索历 程。通过多年的摸索找到了一条切实可行的探索细胞核起源问题的途径。其要点是:在一系列的进化环节中首 先抓住原始性的细胞核这一重要环节,探明原始性细胞核的特性,解决了从原始核到典型细胞核的进化问题, 原始性细胞核自身的起源问题也就有了基础。为探察原始性细胞核的特性,需要在现存的原生生物中间寻找最 原始的类群,然后对它们的细胞核进行尽可能深入地和多方面地研究,对所得结果作进化地分析,以期提出一 个原始性细胞核的模型。依据这个模型也就可以对典型细胞核的进化形成和原始核自身的起源作出推论。而这 些推论是可以设法加以检验的。不仅可以检验这些推论的正确性,而且对原始核模型的建立也是重要的,可以 据之加以发展,修正,甚至否定。沿此途径已经否定了原始性细胞核的涡鞭毛虫核模型,进而提出了双滴虫核 模型。

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报道了美姑脊蛇Achalinus meiguensis线粒体基因组全序列.美姑脊蛇线粒体全序列长17239bp,由22个tRNA,2个rRNA和13个蛋白质基因及2个非编码的控制区或D-loop组成,存在着基因重排现象.对已报道蛇类线粒体基因组全序列进行比对分析后,发现一些蛇类线粒体基因组进化规律:双控制区现象在爬行动物进化历史中独立地发生,有不同的演化历史;tRNA假基因是在真蛇下目(Caenophidia)中进化形成的;TΨC臂的相对较短(一般少于5bp)和缺失"DHU"臂造成蛇类tRNA较短.通过M

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在2006年5月和2006年12月至2007年5月期间,通过使用三层定置刺网捕捉棒花鱼,我们研究了金沙江中游攀枝花江段棒花鱼的生物学。棒花鱼在三层定置刺网中的平均出现率为93.1%,在总渔获物中的平均重量百分比为7.68%;雄性个体的平均体长显著大于雌性个体,体长和体重的回归方程为:W=4×10-5L2.8499(W为体重,L为体长,R2=0.8614);根据鳞片年轮对82尾标本进行了年龄鉴定,其中0龄个体1尾,占1.22%;1龄个体68尾,占82.93%;2龄个体13尾,占15.85%。鳞径与体长显著相

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该研究首次将复合垂直流人工湿地同池塘养殖结合,通过构建养殖-湿地生态系统,验证人工湿地对水产养殖用水和废水净化与回用的可行性。近9个月的新建人工湿地运行结果表明,水力负荷从313、469、625 mm/d增加到781mm/d,人工湿地对TSS、CODC r和BOD5去除率的变动范围分别为80.5%~82.9%、45.2%~64.2%和61.0%~77.0%,对NH4+-N、NO3--N、TN去除率的变动范围分别为51.5%~67.8%-、90.6%~40.0%和29.1%~68.6%,对TP和IP的去除率

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研究了长江上游特有鱼类厚颌鲂的含肉率及其肌肉生化成分和能值。结果表明 :厚颌鲂的含肉率为72 72 % ;其肌肉生化成分 (鲜重百分比 ) :水分含量为 79 2 6%、蛋白质 16 82 %、脂肪 2 10 %、灰分 1 0 8%、无氮浸出物 0 73 %、比能值 4 93KJ/g及E/P2 9 3 3KJ/g。肌肉生化成分含量与体长变化无明显关系。经单因素方差分析 5— 6月份样品与 10月份样品在脂肪和无氮浸出物含量上有显著差异 (P <0 0 5)。肌肉中含有 17种氨基酸 ,总量为69 54%

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目的 从基因水平探讨食管鳞癌HLA DRB1 , DQB1等位基因的遗传易感性 ,以阐述其免疫遗传学特征。方法 运用序列特异性引物聚合酶链反应技术 ,检测无亲缘关系湖北汉族健康人 1 36例、食管鳞癌患者 42例的HLA DRB1 , DQB1等位基因。结果 湖北汉族人食管鳞癌患者与正常人比较 ,HLA DRB1 0 90 1等位基因分布频率显著增高 (0 .2 50 0比 0 .1 397,P =0 .0 2 8,OR =2 .0 53 ,病因分数 =0 .1 2 82 ) ,HLA DQB1 0 30

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Samples from stone surfaces were collected in pools within four unpolluted hillstreams (two shaded and two unshaded) in monsoonal Hong Kong (lat. 23 degrees N) to elucidate the extent of spatial (within and among streams) and temporal (seasonal) variations in algal biomass and assemblage composition. Sampling continued for over 12 months, incorporating the dry season when streams were at baseflow, and the wet season when spates were frequent. We anticipated that algal biomass would be lower in shaded streams and during the wet season, with associated seasonal differences in assemblage composition or relative abundance of different growth forms (e. g. erect versus prostrate). Benthic chlorophyll a (a proxy for algal biomass) varied among streams from an annual mean of 11.0-22.3 mg m(-2). Dry-season standing stocks were 18% higher than during the wet season when spate-induced disturbance reduced algal standing stocks. Algal biomass varied significantly at the stream scale, but not at the pool scale, and was lower in unshaded streams, where standing stocks may have been limited by high densities of algivorous balitorid loaches (mainly Pseudogastromyzon myersi). An overriding effect of grazers on algal biomass could also have reduced variations resulting from spate-induced disturbance. Significant differences in assemblage composition among streams, which were dominated by diatoms and cyanobacteria (totally 82 taxa) were not systematically related to shading conditions. Seasonal variations in algal assemblages were statistically significant but rather minor, and did not involve major shifts in composition or growth form caused by spate-induced disturbance. The abundance of filamentous cyanobacteria in all the streams may have been due to 'gardening' by balitorid loaches that removed erect or stalked diatoms and favoured cyanobacteria that persist through basal regeneration of filaments. This explanation requires validation through manipulative experiments.