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61.
Qian Q Chen Z Ma G Jiang Y Feng Y Shen C Yao Y Ding J Dai Q Li Y 《Molecular biology reports》2009,36(6):1257-1261
Background Inflammation plays an important role in coronary artery disease (CAD). Complement Factor H (CFH) gene has been analyzed in
relation to CAD in several studies with conflicting results. The aim of the present study was to investigate the association
between the CFH Y402H polymorphism and CAD in Chinese. Methods and results About 336 patients were enrolled, included 166 patients with CAD and 170 controls. The SNP at CFH Y402H was genotyped by
ligase detection reaction and plasma levels of CFH were assayed by enzyme-linked immunosorbent assay. Analysis of genotype
frequencies did not reveal any significant difference between CAD patients and controls. There were significant differences
in the frequencies of C allele and C allele carriers between early-onset CAD and controls. After adjustment of clinical parameters,
significant association was identified for CFH Y402H polymorphism, with C allele carriers having a higher risk of early-onset
CAD than carriers of TT genotype (odds ratio [OR] 4.66, 95% CI: 1.23–17.62, P = 0.02). There was no difference of plasma CFH levels between CAD group and controls. Conclusions CFH Y402H polymorphism is associated with early-onset CAD in Chinese.
Qi Qian and Zhong Chen have contributed equally to this paper. 相似文献
62.
Junhao Liu Kai Sun Yongyi Bai Weili Zhang Xiaojian Wang Yibo Wang Hu Wang Jingzhou Chen Xiaodong Song Ying Xin Zhe Liu Rutai Hui 《Human genetics》2009,125(5-6):649-656
Stroke is a common complex trait and does not follow Mendelian pattern of inheritance. Gene–gene or gene–environment interactions may be responsible for the complex trait. How the interactions contribute to stroke is still under research. This study aimed to explore the association between gene–gene interactions and stroke in Chinese in a large case–control study. Nearly 4,000 participants were recruited from seven clinical centers. Eight variants in five candidate genes were examined for stroke risk. Gene–gene interactions were explored by using Generalized Multifactor Dimensionality Reduction (GMDR). A significant gene–gene interaction was found by GMDR. The best model including MTHFR C677T, ALOX5AP T2354A and NOTCH3 C381T scored 10 for Cross-Validation Consistency and 9 for Sign Test (P = 0.0107). The individuals with combination of MTHFR 677TT, ALOX5AP 2354AA and NOTCH3 381TT/TC had a significantly higher risk of thrombotic stroke (OR 3.165, 95% CI 1.461–6.858, P = 0.003). Our results show that combination of these alleles conferred higher risk for stroke than single risk allele. The gene–gene interaction may serve as a novel area for stroke research. The three-locus combination may change the susceptibility of particular subjects to the disease. 相似文献
63.
64.
Jianfeng Sun Yibo Tan Jingyue Su Herasimenka Mikhail Volotovski Pavel Zhenhan Deng Yusheng Li 《Journal of cellular and molecular medicine》2023,27(23):3681-3691
Ghrelin is a brain-gut peptide, and the first 28-peptide that was found in the gastric mucosa. It has a growth hormone (GH)-releasing hormone-like effect and can potently promote the release of GH from pituitary GH cells; however, it is unable to stimulate GH synthesis. Therefore, ghrelin is believed to play a role in promoting bone growth and development. The correlation between ghrelin and some degenerative diseases of the musculoskeletal system has been reported recently, and ghrelin may be one of the factors influencing degenerative pathologies, such as osteoporosis, osteoarthritis, sarcopenia and intervertebral disc degeneration. With population ageing, the risk of health problems caused by degenerative diseases of the musculoskeletal system gradually increases. In this article, the roles of ghrelin in musculoskeletal disorders are summarized to reveal the potential effects of ghrelin as a key target in the treatment of related bone and muscle diseases and the need for further research. 相似文献
65.
66.
三亚岩相潮间带底栖海藻群落结构及其季节变化 总被引:5,自引:0,他引:5
为了解三亚潮间带大型海藻生态现状,布设6条岩相断面,于2008年1—11月进行了四季野外的调查,并使用物种多样性指数与聚类分析研究了潮间带大型海藻四季的群落结构和多样性变化。调查共鉴定出大型底栖藻类130种,隶属于4门75属,其中红藻门41属67种、褐藻门16属31种、绿藻门15属29种、蓝藻门3属3种。潮间带海藻种类数季节变化不大,并呈低潮带>中潮带>高潮带的垂直分布特征,且中低潮带有共同分布种,夏季尤为普遍。潮间带海藻夏冬两季平均生物量高于春秋两季,但并无显著差异。优势种季节变化明显:春季有波利团扇藻Padina boryana、日本仙菜Ceramium japonicum、半叶马尾藻Sargassum hemiphyllum、海柏Polyopes polyideoides,夏季有波状软凹藻Chondrophycus undulates、冠叶马尾藻Sargassum cristaefolium、宽扁叉节藻Amphiroa dilatata、石花菜Gelidium amansii,秋季有冠叶马尾藻、波状软凹藻、叶状铁钉菜Ishige foliacea,冬季有瓦氏马尾藻Sargassum vachellianum、苔状鸭毛藻Symphyocladia marchantioides、珊瑚藻Corallina officinalis、波利团扇藻、日本仙菜。群落多样性冬高夏低:Shannon多样性和Margalef丰富度指数最大值出现在冬季,Shannon多样性和Pielou均匀度指数最低值出现在夏季。区域底栖藻类以暖水性热带-亚热带种为主,其次为温水性的暖温带种类,基本符合南海南区暖水区系特点。研究表明,尽管三亚潮间带底栖海藻种类数与生物量上并无显著的季节差异,但群落结构与多样性均显示出一定的季节变化。 相似文献
67.
Zhibing Jiang Yijun Huang Xiaoqun Xu Yibo Liao Lu Shou Jingjing Liu Quanzhen Chen Jiangning Zeng 《生态学报》2010,30(1):8-15
Recently, the impact of petroleum pollution on marine plankton has been complemented by a great concern. This review summarizes the reports about toxic effects of oil water accommodated fraction (WAF) on marine phytoplankton, zooplankton and early life stage of animal. For the oil WAF, toxicants are mainly composed of the aromatic hydrocarbons, such as the benzene hydrocarbons and polycyclic aromatic hydrocarbons (PAHs) with 2–5 rings. The oil WAF, especially the PAHs, can be accumulated in plankton due to their great lipophilic abilities, and thus elicites various deleterious effects. Toxicological tests show that marine plankton is very sensitive to the petroleum WAF, as the order of median effective/lethal concentration is merely μg/L or mg/L. There are species and developmental stages differences of plankton tolerance to petroleum WAF, and the toxicity of different oil WAF is various. Generally, its toxicity enhances with increasing carbonic chain length and benzene ring number. Many studies on the acute and sub-acute toxic effects of oil WAF have been done, however few researches on its chronic toxic effects has been carried out till now. Besides, most reports focused on the levels from molecule to individual, though very little work of petroleum toxic effects has ever been performed on the marine plankton population or community levels. Therefore, it is necessary to continue these studies in future. 相似文献
68.
Wei Y Huan Y Shi Y Liu Z Bou G Luo Y Zhang L Yang C Kong Q Tian J Xia P Sun QY Liu Z 《PloS one》2011,6(5):e20154
The low success rate of somatic cell nuclear transfer (SCNT) in mammalian cloning is largely due to imprinting problems. However, little is known about the mechanisms of reprogramming imprinted genes during SCNT. Parental origin-specific DNA methylation regulates the monoallelic expression of imprinted genes. In natural fertilization, methylation imprints are established in the parental germline and maintained throughout embryonic development. However, it is unclear whether methylation imprints are protected from global changes of DNA methylation in cloned preimplantation embryos. Here, we demonstrate that cloned porcine preimplantation embryos exhibit demethylation at differentially methylated regions (DMRs) of imprinted genes; in particular, demethylation occurs during the first two cell cycles. By RNAi-mediated knockdown, we found that Dnmt1 is required for the maintenance of methylation imprints in porcine preimplantation embryos. However, no clear signals were detected in the nuclei of oocytes and preimplantation embryos by immunofluorescence. Thus, Dnmt1 is present at very low levels in the nuclei of porcine oocytes and preimplantation embryos and maintains methylation imprints. We further showed that methylation imprints were rescued in nonenucleated metaphase II (MII) oocytes. Our results indicate that loss of Dnmt1 in the maternal nucleus during SCNT significantly contributes to the unfaithful maintenance of methylation imprints in cloned embryos. 相似文献
69.
黄龙沟钙化滩流地由于溪流的作用,在滩流地之间形成面积大小不一的植物群落斑块。这些小尺度斑块面积的大小对植物物种数量的影响尚不清楚。应用回归分析法和幂函数方程对黄龙沟钙化滩流地内的物种-面积关系进行了研究。结果表明黄龙沟钙化滩流地中斑块的大小对物种数(含兰科植物)具有强烈的影响,而调查的其他因子对总的植物物种数量的影响不显著。在所调查的环境因子中,斑块面积对物种数量的影响达到79.5%,即斑块越大,所包含的物种数量越多。兰科植物种类数量除了受斑块面积的影响外,还与距离林缘的距离有关(负相关)。物种-面积关系符合幂函数方程S=cAZ的规律。不同的尺度下,z值略有差异,在中等尺度下 (1-10 m2)最大,为0.2616,较大尺度下(10-100 m2)的最小,z值为0.2050,小尺度下(<1 m2),z值为0.2382。表明中等尺度的斑块(1-10 m2)包含的物种数(含兰科植物)的增长速度最快,而在斑块面积大于10 m2时,物种数增长速度最小。 相似文献
70.
Dunwu Qi Shanning Zhang Zejun Zhang Yibo Hu Xuyu Yang Hongjia Wang Fuwen Wei 《The Journal of wildlife management》2012,76(5):1092-1100
Examining ecological processes across spatial scales is crucial as animals select and use resources at different scales. We carried out field surveys in September 2005, March–September 2006, and April 2007, and used ecological niche factor analysis to determine habitat preferences for the giant panda (Ailuropoda melanoleuca) across 4 spatial scales: daily movement, core range, home range, and seasonal elevational migration. We found that giant pandas prefer conifer forest and mixed forest at higher than average elevation (2,157 m) of study area in the 4 scale models. However, we also observed significant scale differences in habitat selection. The strength of habitat preference increased with scale for the 2 disturbed forests (sparse forest and fragmented forest), and decreased with scale for 0–30° gentle slope and south- and north-facing aspect. Furthermore, habitat suitability patterns were scale-dependent. These findings highlight the need to determine species–environment associations across multiple scales for habitat management and species conservation. © 2012 The Wildlife Society. 相似文献