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The incidence of tuberculosis (TB) and its risk factors in China remains unclear. This study examined TB incidence and relative risk factors in rural areas of China. Participants (n = 177,529) were recruited in Xiangtan County (in the central area of China) and in Danyang County (in the eastern area of China) in 2009 and a followed-up study was conducted for one year. The incidence density of pulmonary TB and smear-positive TB were 91.6 (95% CI: 78.7, 106.0) per 100,000 person-year and 36.7 (95% CI: 33.1, 52.4) per 100,000 person-year respectively in Xiangtan, and 47.3 (95% CI: 38.2, 57.5) per 100,000 person-year and 22.7 (95% CI: 16.5, 30.8) per 100,000 person-year in Danyang. The medical history of TB was associated with TB, with the relative risk (RR) of 7.00 (95% CI: 2.76, 17.18) in Xiangtan and that of 31.08 (95% CI: 13.22, 73.10) in Danyang. The association between TB and per capita living space over median was found in Xiangtan, with the RR of 1.86 (95% CI: 1.15, 3.01). No association was found between TB and the insurance status, the contact history with TB, the history of diabetes, smoking, or per capita annual income. The host genetic susceptibility, and social factors such as education and income could be considered in future studies.  相似文献   
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以克山病病区粮配成基础饲料,另在基础饲料中分别补充Se或VE,或Se+VE喂养大鼠,在细胞及亚细胞水平上以Ca代谢为主研究并比较了Se和VE在克山病病因中的作用。测量了心肌细胞和心肌线粒体的Ca代谢及有关指标、心肌线粒体能量转换功能及心肌组织自由基含量。结果表明,在低Se病区粮中补充Se或VE均能在一定程度上预防病区粮中致病因素对心肌细胞及线粒体的损伤;并且补充Se或VE均能使心肌组织中自由基含量减少。提示Se和VE是通过清除体内过量自由基预防细胞和线粒体的损伤的。但值得注意的是,实验中所用病区粮VE含量不低于甚至高于非病区对照粮,在低Se情况下,所补VE的量需要相当大(如本实验中补充200μg/g)才能较明显地预防心肌细胞和心肌线粒体的损伤。通过对这些结果的分析,进一步肯定低Se是克山病形成的重要因素之一。  相似文献   
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An alkalitolerant, thermotolerant and Gram-stain negative bacterium, designated strain YIM 78007T, was isolated from an alkaline geothermal soil sample from Hehua hot spring, Tengchong, Yunnan province, south-west China. Cells of strain YIM 78007T were observed to be aerobic and short rod-shaped. The colonies were observed to be orange-red, convex and circular. 16S rRNA gene sequence-based phylogenetic analysis showed that strain YIM 78007T clustered with members of the genus Roseomonas (with similarities from 97.2 to 92.2 %). Optimal growth of strain YIM 78007 occurs at 40–50 °C and pH 8.0–10.0. The predominant ubiquinone was identified as Q-10 and the major fatty acids were identified as C18:1 ω7c and C16:0. The polar lipids were identified as diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, two unidentified aminolipids and one unknown phospholipid. The G + C content of the genomic DNA was determined to be 63 mol %. The levels of DNA–DNA hybridization relatedness between strain YIM 78007T and its closet neighbours (Roseomonas lacus JCM 13283T and Roseomonas terrae JCM 14592T) were well below the threshold required for the proposal of a novel species. The results of physiological and biochemical characteristics, the phylogenetic analysis, as well as low DNA–DNA hybridization values, allowed the phenotypic and genotypic differentiation of strain YIM 78007T from its closest phylogenetic neighbours. Therefore, strain YIM 78007T is considered to represent a novel species of the genus Roseomonas, for which the name Roseomonas alkaliterrae sp. nov. is proposed. The type strain is YIM 78007T (=BCRC 80644T = JCM 19656T).  相似文献   
26.
Established populations of Pseudodacrylogyrus anguillae are reported from eels in England for the first time. Prevalence and abundance peak in late summer in all three localities and the parasite overwinters at low levels on eels.  相似文献   
27.
蹄蝠科的核型进化:比较染色体涂色、G带和C带分析(英文)   总被引:1,自引:0,他引:1  
Mao XG  Wang JH  Su WT  Wang YX  Yang FT  Nie WH 《动物学研究》2010,31(5):453-460
与其姐妹科(菊头蝠科)相比,蹄蝠科的细胞遗传学研究较少。迄今为止,仅少数蹄蝠科几个物种有高分辨率的G带核型报道,且有关该科核型进化的大多数结论都是基于常规Giemsa染色研究而得。该研究利用三叶小蹄蝠的染色体特异探针,通过比较染色体涂色、G和C显带,建立了5种蹄蝠的染色体同源性图谱,并探讨了它们同源染色体间的G和C带异同。结果表明:罗伯逊易位、臂内倒位以及异染色质的扩增可能是蹄蝠科物种核型进化的主要机制。通过对这5种蹄蝠物种及其外群物种之间的同源染色体片段的比较分析,作者推测蹄蝠科的祖先核型并不像先前认为的全由端着丝粒染色体组成,而应该含有中着丝粒染色体。  相似文献   
28.
The zebrafish has become an important vertebrate animal model for the study of developmental biology, functional genomics, and disease mechanisms. It is also being used for drug discovery. Computerized detection of blob objects has been one of the important tasks in quantitative phenotyping of zebrafish. We present a new automated method that is able to detect blob objects, such as nuclei or cells in microscopic zebrafish images. This method is composed of three key steps. The first step is to produce a diffused gradient vector field by a physical elastic deformable model. In the second step, the flux image is computed on the diffused gradient vector field. The third step performs thresholding and nonmaximum suppression based on the flux image. We report the validation and experimental results of this method using zebrafish image datasets from three independent research labs. Both sensitivity and specificity of this method are over 90%. This method is able to differentiate closely juxtaposed or connected blob objects, with high sensitivity and specificity in different situations. It is characterized by a good, consistent performance in blob object detection.  相似文献   
29.
Chemically sulfated polysaccharide (S-GAP-P) was derived from water-insoluble polysaccharide of Grifola frondosa mycelia. In this research, we investigated the anticancer effects of S-GAP-P and its combination with 5-fluorouracil (5-FU) on human gastric carcinoma SGC-7901 cells. Results showed that S-GAP-P distinctly inhibited SGC-7901 cells growth in a dose-dependent manner and induced cell apoptosis evidenced by characteristic DNA ladder and sub-G0/G1 peak. Furthermore, the combination of S-GAP-P (10–50 μg/ml) with 1 μg/ml 5-FU resulted in a significant inhibition on SGC-7901 cells growth, meaning the beneficial interaction between the two drugs. All these results suggested that S-GAP-P has evident anticancer activity through apoptotic induction and could significantly accelerate the anticancer activity of 5-FU.  相似文献   
30.
Yi L  Li Z  Yuan K  Qu X  Chen J  Wang G  Zhang H  Luo H  Zhu L  Jiang P  Chen L  Shen Y  Luo M  Zuo G  Hu J  Duan D  Nie Y  Shi X  Wang W  Han Y  Li T  Liu Y  Ding M  Deng H  Xu X 《Journal of virology》2004,78(20):11334-11339
Severe acute respiratory syndrome coronavirus (SARS-CoV) is the pathogen of SARS, which caused a global panic in 2003. We describe here the screening of Chinese herbal medicine-based, novel small molecules that bind avidly with the surface spike protein of SARS-CoV and thus can interfere with the entry of the virus to its host cells. We achieved this by using a two-step screening method consisting of frontal affinity chromatography-mass spectrometry coupled with a viral infection assay based on a human immunodeficiency virus (HIV)-luc/SARS pseudotyped virus. Two small molecules, tetra-O-galloyl-beta-D-glucose (TGG) and luteolin, were identified, whose anti-SARS-CoV activities were confirmed by using a wild-type SARS-CoV infection system. TGG exhibits prominent anti-SARS-CoV activity with a 50% effective concentration of 4.5 microM and a selective index of 240.0. The two-step screening method described here yielded several small molecules that can be used for developing new classes of anti-SARS-CoV drugs and is potentially useful for the high-throughput screening of drugs inhibiting the entry of HIV, hepatitis C virus, and other insidious viruses into their host cells.  相似文献   
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