全文获取类型
收费全文 | 9814篇 |
免费 | 717篇 |
国内免费 | 36篇 |
专业分类
耳鼻咽喉 | 101篇 |
儿科学 | 357篇 |
妇产科学 | 149篇 |
基础医学 | 1410篇 |
口腔科学 | 151篇 |
临床医学 | 867篇 |
内科学 | 1836篇 |
皮肤病学 | 204篇 |
神经病学 | 1144篇 |
特种医学 | 403篇 |
外国民族医学 | 5篇 |
外科学 | 1491篇 |
综合类 | 68篇 |
一般理论 | 6篇 |
预防医学 | 512篇 |
眼科学 | 232篇 |
药学 | 947篇 |
中国医学 | 5篇 |
肿瘤学 | 679篇 |
出版年
2021年 | 117篇 |
2019年 | 97篇 |
2018年 | 146篇 |
2017年 | 105篇 |
2016年 | 154篇 |
2015年 | 178篇 |
2014年 | 194篇 |
2013年 | 286篇 |
2012年 | 381篇 |
2011年 | 434篇 |
2010年 | 221篇 |
2009年 | 215篇 |
2008年 | 353篇 |
2007年 | 402篇 |
2006年 | 405篇 |
2005年 | 364篇 |
2004年 | 422篇 |
2003年 | 402篇 |
2002年 | 322篇 |
2001年 | 343篇 |
2000年 | 335篇 |
1999年 | 267篇 |
1998年 | 113篇 |
1997年 | 117篇 |
1996年 | 109篇 |
1995年 | 82篇 |
1993年 | 80篇 |
1992年 | 218篇 |
1991年 | 219篇 |
1990年 | 215篇 |
1989年 | 246篇 |
1988年 | 222篇 |
1987年 | 198篇 |
1986年 | 193篇 |
1985年 | 211篇 |
1984年 | 136篇 |
1983年 | 96篇 |
1982年 | 86篇 |
1981年 | 80篇 |
1980年 | 84篇 |
1979年 | 140篇 |
1978年 | 96篇 |
1977年 | 83篇 |
1976年 | 111篇 |
1975年 | 102篇 |
1974年 | 96篇 |
1973年 | 74篇 |
1972年 | 74篇 |
1971年 | 87篇 |
1970年 | 83篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
91.
Predicting protein complex membership using probabilistic network reliability 总被引:8,自引:1,他引:8 下载免费PDF全文
Evidence for specific protein-protein interactions is increasingly available from both small- and large-scale studies, and can be viewed as a network. It has previously been noted that errors are frequent among large-scale studies, and that error frequency depends on the large-scale method used. Despite knowledge of the error-prone nature of interaction evidence, edges (connections) in this network are typically viewed as either present or absent. However, use of a probabilistic network that considers quantity and quality of supporting evidence should improve inference derived from protein networks. Here we demonstrate inference of membership in a partially known protein complex by using a probabilistic network model and an algorithm previously used to evaluate reliability in communication networks. 相似文献
92.
The PDZ-binding domain is essential for the dendritic targeting of 5-HT2A serotonin receptors in cortical pyramidal neurons in vitro 总被引:1,自引:0,他引:1
The 5-HT(2A) serotonin receptor represents an important molecular target for atypical antipsychotic drugs and for most hallucinogens. In the mammalian cerebral cortex, 5-HT(2A) receptors are enriched in pyramidal neurons, within which 5-HT(2A) receptors are preferentially sorted to the apical dendrites. In primary cortical cultures, 5-HT(2A) receptors are sorted to dendrites and not found in the axons of pyramidal neurons. We identified a sorting motif that mediates the preferential targeting of 5-HT(2A) receptors to the dendrites of cortical pyramidal neurons in vitro. We constructed green fluorescent protein-tagged 5-HT(2A) receptors wherein potential sorting motifs were disrupted, and subsequently employed either the Semliki Forest virus or calcium phosphate for the transient expression of recombinant 5-HT(2A) receptors in cultured cortical pyramidal neurons. Using dual-labeling immunofluorescent confocal microscopy, we quantified the axonal and dendritic sorting patterns of endogenous and recombinant 5-HT(2A) receptors. We discovered that disruption of the PDZ-binding domain of the 5-HT(2A) receptor greatly attenuates the dendritic targeting of 5-HT(2A) receptors without inappropriately sorting 5-HT(2A) receptors to axons. The PDZ-binding domain is therefore a necessary signal for the preferential targeting of the 5-HT(2A) receptor to the dendritic compartment of cultured cortical pyramidal neurons, the first such role ascribed to this protein-protein interaction motif of any G protein-coupled receptor. 相似文献
93.
94.
Endometriosis with perineural involvement 总被引:1,自引:0,他引:1
L M Roth 《American journal of clinical pathology》1973,59(6):807-809
95.
Rabon-Stith KM Hagberg JM Phares DA Kostek MC Delmonico MJ Roth SM Ferrell RE Conway JM Ryan AS Hurley BF 《Experimental physiology》2005,90(4):653-661
To determine the influence of the vitamin D receptor (VDR) gene FokI and BsmI genotype on bone mineral density response to two exercise training modalities, 206 healthy men and women (50-81 years old) were studied before and after approximately 5-6 months of either aerobic exercise training (AT) or strength training (ST). A totla of 123 subjects completed AT (51 men, 72 women) and 83 subjects completed ST (40 men, 43 women). DNA was extracted from blood samples of all subjects and genotyping was performed at the VDR FokI and BsmI locus to determine its association to training response. Total body, greater trochanter and femoral neck bone mineral density (BMD) were measured before and after both training programmes using dual-energy X-ray absorptiometry. VDR BsmI genotype was not significantly related to BMD at baseline or after ST or AT. However, VDR FokI genotype was significantly related to ST- but not AT-induced changes in femoral neck BMD (P < 0.05). The heterozygotes (Ff) in the ST group approached a significantly greater increase in femoral neck BMD (P = 0.058) compared to f homozygotes. There were no significant genotype relationships in the AT group. These data indicate that VDR FokI genotype may influence femoral neck BMD response to ST, but not AT. 相似文献
96.
Elahé T Crockett James J Galligan Bruce D Uhal Jack Harkema Robert Roth Kinnari Pandya 《BMC clinical pathology》2006,6(1):3-13
Background
Cytokine production is critical in ischemia/reperfusion (IR) injury. Acetylcholine binds to macrophages and inhibits cytokine synthesis, through the cholinergic anti-inflammatory pathway. This study examined the role of the cholinergic pathway in cytokine production and hepatic IR- injury. 相似文献97.
Ciancio G Burke GW Roth D Miller J 《BioDrugs : clinical immunotherapeutics, biopharmaceuticals and gene therapy》1999,11(6):395-407
Immunosuppression, although necessary to enable the graft to escape the consequences of immune surveillance, carries some risks for the patient. There is an associated increase in neoplasms, opportunistic infections and end-organ toxicity. In addition, even with excellent patient compliance, rejection (acute and chronic) remains a major limitation that contributes to the loss or decrease in the function of the allograft. New drugs have been added to the armamentarium of immunosuppressive agents to suppress allograft rejection and to rescue grafts from cyclosporin-resistant rejection. With the availability of these immunosuppressive agents, it has become increasingly difficult to choose the appropriate combination of immunosuppressants with a beneficial effect for the patient and for the allograft. We describe 2 new immunosuppressive agents and some of their different uses in solid organ transplantation. 相似文献
98.
The honeybee syndrome - implications of the teratogenicity of mannose in rat-embryo culture 总被引:6,自引:0,他引:6
N Freinkel N J Lewis S Akazawa S I Roth L Gorman 《The New England journal of medicine》1984,310(4):223-230
Lethal effects of D-mannose in the honeybee have been recognized for more than a half a century. We observed another toxic effect of D- mannose during culture of rat embryos from the early head-fold stage to the 26-to-29-somite stage (Days 9-1/2 through 11-1 of gestation). The addition to culture mediums of 1.5 mg of D-mannose per milliliter caused growth retardation and faulty neural-tube closure in approximately two thirds of the embryos. Mannose effects occurred during the first 24 hours of culture and were attended by modes inhibition of the glycolysis that constitutes the principal energy pathway at this stage of development. Adding more glucose to preserve glycolytic flux or increasing atmospheric oxygen to promote oxidative metabolism offset the mannose teratogenesis. Our findings highlight the metabolic vulnerabilities that exist during early organogenesis, before oxidative flexibility is established. They may serve as a model to explain the teratogenicity of many other seemingly unrelated agents that could act by perturbing glycolysis at this vulnerable stage. 相似文献
99.
Coppin H Ribouchon MT Bausero P Pessac B Fontaine B Semana G Clanet M Roth MP;French Multiple Sclerosis Genetics Group 《Genes and immunity》2000,1(8):478-482
The myelin basic protein (MBP) gene is a candidate locus for susceptibility to multiple sclerosis. Several groups have tested a complex (TGGA)n repeat in the 5' region of this gene for association/linkage with multiple sclerosis, with divergent results. This region of tandem repetitive sequence has been subjected to complex rearrangements, and there is a possibility that alleles of the same size have different internal structures, which reduces the interest of this marker for linkage disequilibrium studies and may at least partly explain the conflicting results obtained so far. To overcome this problem, we isolated a new polymorphic (CA)n repeat within the Golli-MBP locus. The limited number of alleles identified makes this other marker suitable for transmission disequilibrium studies. We tested this marker for linkage with multiple sclerosis, using the transmission-disequilibrium test (TDT) on a sample of 196 nuclear families in which the genotypes of both parents could be unambiguously defined. We found no evidence of transmission disequilibrium between multiple sclerosis and any of the three alleles of this marker, even when the patients were subdivided according to their HLA-DRB1*1501 status. The present data thus provide no evidence for a contribution of the MBP gene to multiple sclerosis susceptibility in French patients. 相似文献
100.
Possible changes in membrane lipid assemetry may result in altered function with aging. Membrane proteolysis is an additional factor which must be considered, both with respect to modulation of membrane function and also as a methodological problem in analyses of membrane dynamics. 相似文献