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排序方式: 共有343条查询结果,搜索用时 271 毫秒
281.
Gudmundsson J Sulem P Rafnar T Bergthorsson JT Manolescu A Gudbjartsson D Agnarsson BA Sigurdsson A Benediktsdottir KR Blondal T Jakobsdottir M Stacey SN Kostic J Kristinsson KT Birgisdottir B Ghosh S Magnusdottir DN Thorlacius S Thorleifsson G Zheng SL Sun J Chang BL Elmore JB Breyer JP McReynolds KM Bradley KM Yaspan BL Wiklund F Stattin P Lindström S Adami HO McDonnell SK Schaid DJ Cunningham JM Wang L Cerhan JR St Sauver JL Isaacs SD Wiley KE Partin AW Walsh PC Polo S Ruiz-Echarri M 《Nature genetics》2008,40(3):281-283
We conducted a genome-wide SNP association study on prostate cancer on over 23,000 Icelanders, followed by a replication study including over 15,500 individuals from Europe and the United States. Two newly identified variants were shown to be associated with prostate cancer: rs5945572 on Xp11.22 and rs721048 on 2p15 (odds ratios (OR) = 1.23 and 1.15; P = 3.9 x 10(-13) and 7.7 x 10(-9), respectively). The 2p15 variant shows a significantly stronger association with more aggressive, rather than less aggressive, forms of the disease. 相似文献
282.
二分图模型是一种全局优化算法,本文将二分图模型应用于直接推荐众筹项目,使用PersonalRank算法迭代计算网络节点的全局关联度,从而推荐那些基于余弦相似度的协同过滤不能有效推荐的项目,适用性更加广泛.更进一步,提出将二分图模型与协同过滤算法相结合,首先把网络结构划分为二分图,采用二分图算法得到的两类节点(用户节点,项目节点)之间的全局相似度,再结合协同过滤算法,得到基于二分图模型的协同过滤算法.实验表明,在众筹项目推荐中,由于数据极端稀疏,适宜采用二分图模型来进行相似度计算并进行推荐. 相似文献
283.
During an investigation of species diversity in the Lengshuihe Nature Preserve, Jinsha County, Guizhou Province, China, in August of 2015, a new species of the rare genus Gibbotettix was discovered. Gibbotettix vallis Zha and Wen sp. nov. is introduced, described and photographed, and compared with other species. A taxonomic review of the genus Gibbotettix is provided and a key to all known species of the genus is given.
http://zoobank.org/urn:lsid:zoobank.org:pub:74D8DCB9-A31E-4E4D-A2E8-692A54A81317 相似文献
284.
Jacobs KB Yeager M Zhou W Wacholder S Wang Z Rodriguez-Santiago B Hutchinson A Deng X Liu C Horner MJ Cullen M Epstein CG Burdett L Dean MC Chatterjee N Sampson J Chung CC Kovaks J Gapstur SM Stevens VL Teras LT Gaudet MM Albanes D Weinstein SJ Virtamo J Taylor PR Freedman ND Abnet CC Goldstein AM Hu N Yu K Yuan JM Liao L Ding T Qiao YL Gao YT Koh WP Xiang YB Tang ZZ Fan JH Aldrich MC Amos C Blot WJ Bock CH Gillanders EM Harris CC Haiman CA Henderson BE Kolonel LN Le Marchand L McNeill LH 《Nature genetics》2012,44(6):651-658
In an analysis of 31,717 cancer cases and 26,136 cancer-free controls from 13 genome-wide association studies, we observed large chromosomal abnormalities in a subset of clones in DNA obtained from blood or buccal samples. We observed mosaic abnormalities, either aneuploidy or copy-neutral loss of heterozygosity, of >2 Mb in size in autosomes of 517 individuals (0.89%), with abnormal cell proportions of between 7% and 95%. In cancer-free individuals, frequency increased with age, from 0.23% under 50 years to 1.91% between 75 and 79 years (P = 4.8 × 10(-8)). Mosaic abnormalities were more frequent in individuals with solid tumors (0.97% versus 0.74% in cancer-free individuals; odds ratio (OR) = 1.25; P = 0.016), with stronger association with cases who had DNA collected before diagnosis or treatment (OR = 1.45; P = 0.0005). Detectable mosaicism was also more common in individuals for whom DNA was collected at least 1 year before diagnosis with leukemia compared to cancer-free individuals (OR = 35.4; P = 3.8 × 10(-11)). These findings underscore the time-dependent nature of somatic events in the etiology of cancer and potentially other late-onset diseases. 相似文献
285.
286.
Variation in factor B (BF) and complement component 2 (C2) genes is associated with age-related macular degeneration 总被引:1,自引:0,他引:1
Gold B Merriam JE Zernant J Hancox LS Taiber AJ Gehrs K Cramer K Neel J Bergeron J Barile GR Smith RT;AMD Genetics Clinical Study Group Hageman GS Dean M Allikmets R 《Nature genetics》2006,38(4):458-462
Age-related macular degeneration (AMD) is the most common form of irreversible blindness in developed countries. Variants in the factor H gene (CFH, also known as HF1), which encodes a major inhibitor of the alternative complement pathway, are associated with the risk for developing AMD. Here we test the hypothesis that variation in genes encoding other regulatory proteins of the same pathway is associated with AMD. We screened factor B (BF) and complement component 2 (C2) genes, located in the major histocompatibility complex class III region, for genetic variation in two independent cohorts comprising approximately 900 individuals with AMD and approximately 400 matched controls. Haplotype analyses identify a statistically significant common risk haplotype (H1) and two protective haplotypes. The L9H variant of BF and the E318D variant of C2 (H10), as well as a variant in intron 10 of C2 and the R32Q variant of BF (H7), confer a significantly reduced risk of AMD (odds ratio = 0.45 and 0.36, respectively). Combined analysis of the C2 and BF haplotypes and CFH variants shows that variation in the two loci can predict the clinical outcome in 74% of the affected individuals and 56% of the controls. These data expand and refine our understanding of the genetic risk for AMD. 相似文献
287.
288.
Kevin Fergusson 《Journal of forecasting》2020,39(1):37-46
In this paper we investigate the applicability of several continuous-time stochastic models to forecasting inflation rates with horizons out to 20 years. While the models are well known, new methods of parameter estimation and forecasts are supplied, leading to rigorous testing of out-of-sample inflation forecasting at short and long time horizons. Using US consumer price index data we find that over longer forecasting horizons—that is, those beyond 5 years—the log-normal index model having Ornstein–Uhlenbeck drift rate provides the best forecasts. 相似文献
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290.
Spinal cord injuries often occur at the cervical level above the phrenic motor pools, which innervate the diaphragm. The effects of impaired breathing are a leading cause of death from spinal cord injuries, underscoring the importance of developing strategies to restore respiratory activity. Here we show that, after cervical spinal cord injury, the expression of chondroitin sulphate proteoglycans (CSPGs) associated with the perineuronal net (PNN) is upregulated around the phrenic motor neurons. Digestion of these potently inhibitory extracellular matrix molecules with chondroitinase ABC (denoted ChABC) could, by itself, promote the plasticity of tracts that were spared and restore limited activity to the paralysed diaphragm. However, when combined with a peripheral nerve autograft, ChABC treatment resulted in lengthy regeneration of serotonin-containing axons and other bulbospinal fibres and remarkable recovery of diaphragmatic function. After recovery and initial transection of the graft bridge, there was an unusual, overall increase in tonic electromyographic activity of the diaphragm, suggesting that considerable remodelling of the spinal cord circuitry occurs after regeneration. This increase was followed by complete elimination of the restored activity, proving that regeneration is crucial for the return of function. Overall, these experiments present a way to markedly restore the function of a single muscle after debilitating trauma to the central nervous system, through both promoting the plasticity of spared tracts and regenerating essential pathways. 相似文献