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排序方式: 共有853条查询结果,搜索用时 15 毫秒
81.
ABSTRACT: BACKGROUND: Vertebral artery dissection (VAD) is often associated with trauma or occurs spontaneously, inevitably causing some neurological deficits. Even though acute infection can be related to the development of spontaneous VAD (sVAD), VAD associated with viral meningitis has never been reported in the literature. CASE PRESENTATION: A 42-year-old man with fever, sore throat, and runny nose developed sudden onset of occipital headache, vertigo, transient confusion, diplopia, and ataxia. Brain stem encephalitis was diagnosed initially because the cerebrospinal fluid (CSF) study showed inflammatory changes. However, subsequent diffusion-weighted (DWI) magnetic resonance imaging of his brain demonstrated left lateral medullary infarction, and the digital subtraction angiography (DSA) confirmed VAD involving left V4 segment of the artery. Consequently, the patient was diagnosed as VAD accompanied by viral meningitis. CONCLUSION: This case suggests that viral meningitis might lead to inflammatory injury of the vertebral arterial wall, even sVAD with multiple neurological symptoms. 相似文献
82.
Stable silencing of β-lactoglobulin (BLG) gene by lentivirus-mediated RNAi in goat fetal fibroblasts
Shumin Zhang Kai Xiong Zhourui Xie Wenting Nan Honglin Liu Jie Chen 《Genetics and molecular biology》2012,35(3):680-685
β-lactoglobulin (BLG), a dominant allergen in goat milk, is difficult to remove by traditional biochemical methods. Its elimination from goat milk by genetic modification therefore poses a major challenge for modern goat breeders. A shRNA targeting BLG mRNA with high interference efficiency was identified, with which lentiviral vectors were used for mediating stable shRNA interference in goat-fetal fibroblast cells. Apart from high efficiency in the knockdown of BLG expression in these cells, lentivector-mediated RNAi manifested stable integration into the goat genome itself. Consequently, an in vitro model for goat BLG-content control was compiled, and a goat-cell line for accompanying transgenetic goat production created. 相似文献
83.
Chemokines are potent proinflammatory cytokines that are implicated in numerous inflammatory diseases. Monocyte chemoattractant protein-1 (MCP-1) and its receptor CC chemokine receptor-2 (CCR2) play a major role in the recruitment of inflammatory cells to the lungs of patients with chronic obstructive pulmonary disease (COPD). We investigated a possible association between polymorphisms in MCP-1 and CCR2 genes (MCP-1 -2518 A/G and CCR2 190G/A or V64I) and the development of COPD. Genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism in 386 COPD cases and 398 age-matched healthy controls. Frequency of MCP-1 2518GG genotype for cases and controls was 0.396 and 0.324, respectively; individuals who had the GG genotype had a 1.59-fold increased risk of COPD (p=0.036). Frequency of CCR2 190AA (64I/64I) genotype for cases and controls was 0.285 and 0.21, respectively; subjects carrying the 64I/64I genotype had a 2.04-fold increased risk of COPD compared with the wild-type genotype (p=0.001). When analyzing the allele combination of these two polymorphisms, the combinations MCP-1-A/CCR2-A and MCP-1-G/CCR2-A were detected in significantly higher numbers in COPD cases than in healthy controls (odds ratio [OR]=1.50, 95% confidence interval [CI]: 1.04-2.17, p=0.032; and OR=1.89, 95% CI: 1.38-2.60, p=7.38×10(-5)). These data suggest that MCP-1 -2518 A/G and CCR2 190G/A polymorphisms are new risk factors for COPD. 相似文献
84.
JH Lin MJ Gunter JE Manson KM Rexrode NR Cook P Kraft BB Cochrane RT Chlebowski GY Ho SM Zhang 《PloS one》2012,7(7):e42079
Background
Estrogen and androgen have been linked to the regulation of circulating hepatocyte growth factor (HGF), an adipose tissue-derived cytokine. It is possible that the CYP19A1 gene which alters sex hormones production may influence HGF levels. We examined the association between the CYP19A1 gene variants and plasma HGF concentrations.Design
We evaluated 45 common and putative functional variants of CYP19A1 and circulating levels of HGF among 260 postmenopausal women who later developed colorectal cancer from the Women''s Health Initiative Observational Cohort. As the distribution of HGF levels was highly skewed, we transformed HGF concentrations for all women into a log-, ranked-, or normal score-scale value. Multiple linear regression with adjustment for age was used to evaluate the associations.Results
We observed an association between the rs7172156, rs1008805, rs6493494, rs749292, and rs11636639 variants and HGF levels in ranked and normal score scales (corrected p values ≤0.02), although the association of these 5 SNPs with log-scale HGF was not significant (corrected p values ≥0.16). The associations remained unchanged after additional adjustment for hormone therapy use and estradiol levels. These 5 SNPs, which were in linkage disequilibrium (pairwise D′≥97%, r2≥56%), constituted a block with 2 common haplotypes accounting for 82% frequency. The most common haplotype, TCCCA, was associated with lower ranked- or normal score-transformed HGF levels (corrected p values ≤0.001), whereas the second most common haplotype, CTTCA, was associated with higher ranked- or normal score-transformed HGF levels (corrected p values ≤0.02).Conclusion
Our findings of a potential association between the CYP19A1 variants and circulating HGF levels warrant confirmation in studies with larger sample size. 相似文献85.
中国畜禽粪便污染现状及产沼气潜力 总被引:38,自引:0,他引:38
为弄清中国畜禽粪便排放总量、污染现状及其资源化潜力,通过查阅文献确定了主要估算参数,并结合畜牧业统计数据估算了2009年中国畜禽粪便排放量及其污染物含量、粪便农用地负荷并对畜禽粪便中氮、磷农用地负荷进行预警分级;同时估算了粪便资源沼气潜力。结果表明:2009年中国畜禽养殖业粪便排放总量为32.64亿t鲜重,其中BOD、COD含量分别为7273.95和8039.96万t。全国单位面积农用地畜禽粪便负荷为26.8t·hm-2,氮、磷素负荷分别为158.42和47.92kg·hm-2。预警分级显示:牧区畜禽养殖业对环境不构成威胁;农区除山西、黑龙江外,其他地区均出现不同程度的氮素污染,而磷素的影响在农区普遍存在。2009年畜禽粪便资源沼气潜力约1200亿m3,其中,大中型畜禽养殖场沼气潜力为240亿m3,约合天然气135亿m3。目前沼气工程已成为环境保护和能源结构调整的一种重要手段。 相似文献
86.
目的构建含有不同长度EphA3基因启动子片段的报告基因载体,研究其在293T细胞和MEF细胞中的转录活性。方法以Balb/C小鼠基因组DNA为模板,扩增不同长度的EphA3基因启动子片段,并克隆进入荧光素酶报告基因质粒pGL3-Basic真核表达载体内。酶切鉴定及基因测序无误后,将重组质粒和pRL—CMV内对照质粒共转染293T和MEF细胞,分析不同长度的OhA3基因启动子片段的转录活性。结果酶切和测序鉴定表明表达载体构建成功,EphA3基因的核心启动子区域位于-279bp~+110bp之间,在293T细胞和MEF细胞中其转录活性相似。结论成功构建了荧光素报告基因重组质粒,并确定了BphA3基因的核心启动子区域。 相似文献
87.
研究欧洲和中国的标本后发现,室翅长蝽科Heterogastridae的小异腹长蝽Heterogaster minimusZou&Zheng,1981是地长蝽科Rhyparochromidae的红足点胸长蝽Acompus rufipes(Wolff,1804)的新异名。文中还提供了红足点胸长蝽Acompus rufipes的整体图和雄性生殖器特征图。 相似文献
88.
记载中国网蝽科1新记录属:海氏网蝽属Heissiella Péricart,1984(国外分布:印度,不丹;国内分布:海南),及1新种:华海氏网蝽Heissiella sinica sp.nov.。文中提供了新种成虫背面观照片、雌雄性生殖器特征图及该属种检索表。 相似文献
89.
90.
在昆虫纲中,生命树计划正在以目级阶元中的分类单元为单位逐步推进.针对这一大的背景,以及高级阶元和种级阶元分子系统学研究间脱节现状,提出以rDNA簇为一组分子标记、并且在未来高级阶元系统发育研究中将目前选取少量代表类群的做法改为将尽量多的物种包含到一棵系统发育树中的建议.其中首先简要介绍了rDNA簇的结构及其中各分子标记在分子系统学研究中的应用价值,随后以蝽类昆虫为例,有针对性地总结了rDNA簇中不同基因序列已有数据的丰富程度及其在分子系统学研究中的应用情况.首次给出了蝽类昆虫28S rRNA近全长序列的二级结构模型.基于对18S rRNA和28S rRNA二级结构研究所积累的认识,强调了18S rDNA和28S rDNA内部不同区段之间变异模式和应用价值的差异,论证了未来在生命树构建中深化对rDNA簇中各基因进行联合应用的合理性和可行性. 相似文献