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外源性五羟色胺大鼠肺出血模型及其与浓度关系 总被引:1,自引:0,他引:1
目的 通过外源性五羟色胺 (5 -HT)气管滴入建立新生大鼠肺出血模型及其与浓度关系 .方法 模型制作 :日龄 4~ 5天Wistar二级大鼠 5 0只 ,随机分为 4组 :生理盐水对照组 (A组 )及 3种不同浓度外源性 5 -HT实验组(B、C、D组 ) :经气管导管分别滴入生理盐水和不同浓度 5 -HT ,4小时后处死 ,观察肺大体及组织病理改变 ,将肺出血程度分为 5级 :Ⅰ正常 ;Ⅱ肺水肿 ;Ⅲ点状肺出血 ;Ⅳ局灶性肺出血 ;Ⅴ弥漫性肺出血 ,选择出制作肺出血模型的最佳的浓度 .结果 不同浓度 5 -HT气管内滴入均能引起不同程度肺出血 ,但随着浓度增加 ,B、C、D三组间的肺出血程度无差异 (p >0 .0 5 ) ,其中D组死亡率 30 % ,对照组及B组和C组均无死亡 ,死亡鼠肺为弥漫性出血 .结论 5 -HT可致大鼠肺出血 ,以 1× 10 -5mol/ml浓度为宜 ,随着 5 -HT浓度增加 ,大鼠死亡率增加 ,但肺出血发生率无差异 相似文献
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Ribasés M Gratacòs M Fernández-Aranda F Bellodi L Boni C Anderluh M Cavallini MC Cellini E Di Bella D Erzegovesi S Foulon C Gabrovsek M Gorwood P Hebebrand J Hinney A Holliday J Hu X Karwautz A Kipman A Komel R Nacmias B Remschmidt H Ricca V Sorbi S Wagner G Treasure J Collier DA Estivill X 《Human molecular genetics》2004,13(12):1205-1212
Several genes with an essential role in the regulation of eating behavior and body weight are considered candidates involved in the etiology of eating disorders (ED), but no relevant susceptibility genes with a major effect on anorexia nervosa (AN) or bulimia nervosa (BN) have been identified. Brain-derived neurotrophic factor (BDNF) has been implicated in the regulation of food intake and body weight in rodents. We previously reported a strong association of the Met66 allele of the Val66Met BDNF variant with restricting AN (ANR) and low minimum body mass index in Spanish patients. Another single nucleotide polymorphism located in the promoter region of the BDNF gene (-270C>T) showed lack of association with any ED phenotype. In order to replicate these findings in a larger sample, we performed a case-control study in 1142 Caucasian patients with ED consecutively recruited in six different centers from five European countries (France, Germany, Italy, Spain and UK) participating in the 'Factors in Healthy Eating' project. We have found that the Met66 variant is strongly associated to all ED subtypes (AN, ANR, binge-eating/purging AN and BN), and that the -270C BDNF variant has an effect on BN and late age at onset of weight loss. These are the first two variants associated with the pathophysiology of ED in different populations and support a role for BDNF in the susceptibility to aberrant eating behaviors. 相似文献
45.
选用免32只,手术截除桡骨2cm。缺损区充填DGB,手术后2、3、6、9周分别杀死动物作光镜及电镜观察。结果在电镜下发现有三类细胞,即成骨系、破基质系细胞和血管内皮细胞,并见到非成骨性结缔组织的间充质细胞分化为前成骨细胞→成骨细胞→骨细胞以及其同时分化为血管内皮细胞的全部过程。表实验从组织学和细胞学二方面证实DGB确有诱导成骨的作用。 相似文献
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Xun Wang Rongzuo Xu Grant Abernathey Jordan Taylor M B Alzghoul Kevin Hannon Gregory H Hockerman Amber L Pond 《Developmental dynamics》2008,237(9):2430-2437
The Kv11.1 (also ERG1) K(+) channel underlies cardiac I(Kr), a current that contributes to repolarization in mammalian heart. In mice, I(Kr) current density decreases with development and studies suggest that changes in the structure and/or properties of the heteromultimeric I(Kr)/Kv11.1 channel are responsible. Here, using immunohistochemistry, we report that total Kv11.1 alpha subunit protein is more abundant in neonatal heart and is distributed throughout both adult and neonatal ventricles with greater abundance in epicardia. Immunoblots reveal that the alpha subunit alternative splice variant, Kv11.1a, is more abundant in adult heart while the Kv11.1b variant is more abundant in neonatal heart. Additionally, MinK channel subunit protein is shown to co-assemble with Kv11.1 protein and is more abundant in neonatal heart. In summary, Kv11.1/I(Kr) channel composition varies developmentally and the higher I(Kr) current density in neonatal heart is likely attributable to higher abundance of Kv11.1/I(Kr) channels, more specifically, the Kv11.1b splice variant. 相似文献
48.
目的:构建细胞核定位的抗CydinD1胞内抗体基因的真核表达载体并分析其对乳腺癌细胞增殖的抑制效应。方法:利用PCR技术和分子克隆技术,构建编码细胞核定位的抗CydinD1胞内抗体基因(AD5N)的真核表达载体pcDNA3.1-ADSN,利用脂质体介导法转染MCF-7细胞,RT-PCR、间接免疫荧光、Westernblot和流式细胞术分析该胞内抗体基因ADSN在MCF-7细胞中的表达、定位及抑瘤效应。结果:经限制性内切酶分析及序列分析发现,成功构建编码细胞核定位的抗CyclinD1胞内抗体(AD5N)基因的真核表达载体pcDNA3.1-ADSN,基因片段为855bp,编码285个氨基酸,分子量约为30kD。RT-PCR、免疫荧光及Westernblot实验结果显示,仅在转染胞内抗体基因的MCF-7细胞中存在该胞内抗体的表达,并且主要分布在细胞核区域。与野生型MCF-7细胞和转染空质粒的细胞相比,在MCF-7/pcDNA3.1-ADSN细胞中ADSN的表达可明显抑制MCF-7细胞增殖,显著诱导细胞凋亡(P〈0.01),使G0-G1期细胞周期指数增高12.64%,S期指数下降15.22%,凋亡细胞指数上升9.15%。结论:细胞核定位的抗CyclinD1胞内抗体ADSN基因的表达,可有效抑制乳腺癌细胞的增殖,阻滞细胞周期进展,并诱导细胞凋亡。 相似文献
49.
Xun Shen J Michael Collier Myint Hlaing Leanne Zhang Elizabeth H Delshad James Bristow Harold S Bernstein 《Developmental dynamics》2003,226(1):128-138
Skeletal and cardiac myocytes cease division within weeks of birth. Although skeletal muscle retains limited capacity for regeneration through recruitment of satellite cells, resident populations of adult myocardial stem cells have not been identified. Because cell cycle withdrawal accompanies myocyte differentiation, we hypothesized that C2C12 cells, a mouse myoblast cell line previously used to characterize myocyte differentiation, also would provide a model for studying cell cycle withdrawal during differentiation. C2C12 cells were differentiated in culture medium containing horse serum and harvested at various time points to characterize the expression profiles of known cell cycle and myogenic regulatory factors by immunoblot analysis. BrdU incorporation decreased dramatically in confluent cultures 48 hr after addition of horse serum, as cells started to form myotubes. This finding was preceded by up-regulation of MyoD, followed by myogenin, and activation of Bcl-2. Cyclin D1 was expressed in proliferating cultures and became undetectable in cultures containing 40% fused myotubes, as levels of p21(WAF1/Cip1) increased and alpha-actin became detectable. Because C2C12 myoblasts withdraw from the cell cycle during myocyte differentiation following a course that recapitulates this process in vivo, we performed a genome-wide screen to identify other gene products involved in this process. Using microarrays containing approximately 10,000 minimally redundant mouse sequences that map to the UniGene database of the National Center for Biotechnology Information, we compared gene expression profiles between proliferating, differentiating, and differentiated C2C12 cells and verified candidate genes demonstrating differential expression by RT-PCR. Cluster analysis of differentially expressed genes revealed groups of gene products involved in cell cycle withdrawal, muscle differentiation, and apoptosis. In addition, we identified several genes, including DDAH2 and Ly-6A, whose expression specifically was up-regulated during cell cycle withdrawal coincident with early myoblast differentiation. 相似文献
50.
目的:利用黄金数比例规律找出环境物理因子对人体的最佳条件:方法:人体的相当一部分内容与黄金数有着密切的联系,为此把复杂的人体可以简化为比例加破缺的比例实体;环境物理因子:如环境温度、湿度、环境光波和声波以及环境气压和氧分压,当它们处在黄金数比例附近时,会在人体产生和谐合柏作用。结果:环境物理因子选择在黄金数比例附近时,在心理上产生美和舒适感。已经发现,当精神愉快时,人脑电波频率下限(8Hz)和上限(12.9Hz)之比恰为黄金数。结论:环境物理因子的最佳条件是可以选择的。 相似文献