全文获取类型
收费全文 | 3755篇 |
免费 | 200篇 |
国内免费 | 17篇 |
专业分类
耳鼻咽喉 | 73篇 |
儿科学 | 242篇 |
妇产科学 | 40篇 |
基础医学 | 415篇 |
口腔科学 | 54篇 |
临床医学 | 277篇 |
内科学 | 755篇 |
皮肤病学 | 60篇 |
神经病学 | 309篇 |
特种医学 | 96篇 |
外科学 | 357篇 |
综合类 | 122篇 |
一般理论 | 1篇 |
预防医学 | 188篇 |
眼科学 | 326篇 |
药学 | 384篇 |
中国医学 | 21篇 |
肿瘤学 | 252篇 |
出版年
2024年 | 3篇 |
2023年 | 28篇 |
2022年 | 81篇 |
2021年 | 155篇 |
2020年 | 86篇 |
2019年 | 115篇 |
2018年 | 127篇 |
2017年 | 98篇 |
2016年 | 147篇 |
2015年 | 128篇 |
2014年 | 200篇 |
2013年 | 265篇 |
2012年 | 335篇 |
2011年 | 303篇 |
2010年 | 165篇 |
2009年 | 122篇 |
2008年 | 213篇 |
2007年 | 229篇 |
2006年 | 248篇 |
2005年 | 191篇 |
2004年 | 177篇 |
2003年 | 145篇 |
2002年 | 125篇 |
2001年 | 35篇 |
2000年 | 33篇 |
1999年 | 21篇 |
1998年 | 11篇 |
1997年 | 16篇 |
1996年 | 9篇 |
1995年 | 12篇 |
1994年 | 6篇 |
1993年 | 7篇 |
1992年 | 12篇 |
1991年 | 13篇 |
1990年 | 15篇 |
1989年 | 14篇 |
1988年 | 9篇 |
1987年 | 6篇 |
1986年 | 10篇 |
1985年 | 4篇 |
1983年 | 4篇 |
1982年 | 4篇 |
1979年 | 5篇 |
1977年 | 3篇 |
1975年 | 4篇 |
1974年 | 3篇 |
1973年 | 3篇 |
1970年 | 11篇 |
1968年 | 2篇 |
1967年 | 2篇 |
排序方式: 共有3972条查询结果,搜索用时 341 毫秒
61.
62.
63.
64.
Dinesh Bisht M.D. Surjit Singh M.D. Ranjana W. Minz M.D. Veena Dhawan Ph.D. 《Pediatric dermatology》2013,30(6):695-699
Henoch‐Schönlein purpura (HSP) is an acute systemic vasculitis with unknown etiology, although several studies have found HSP to be related to cytokines such as tumor necrosis factor α, interleukin (IL)‐1, and adhesion molecules. In the present study we determined the levels of cytokines such as IL‐18 and endothelin‐1 (ET‐1) in children with HSP. Subjects were divided into three groups (group 1, 20 subjects with HSP; group 2, 10 subjects belonging to group 1 during their follow‐up 4 to 6 months later; and group 3, 16 controls who were healthy siblings of the subjects). IL‐18 and ET‐1 levels were determined using enzyme immunoassay and expressed as mean ± standard deviation. We observed higher IL‐18 levels in children with HSP (767.6 ± 145.1 pg/mL) than in controls (614.6 ± 66.54 pg/mL, p > 0.05), but IL‐18 levels were found to be significantly lower in subjects with HSP in remission (502.7 ± 60.81 pg/mL) than in those who were in an active phase (1,050 ± 244.5 pg/mL, p < 0.05, n = 10). ET‐1 levels were found to be significantly higher in subjects with HSP (1.93 ± 0.19 pg/mL) than in controls (1.10 ± 0.13 pg/mL, p < 0.05), although no significant difference was observed in ET‐1 levels between subjects in group 1 (1.88 ± 0.30 pg/mL) and group 2 (1.91 ± 0.120, p > 0.05, n = 10). A positive correlation was observed between IL‐18 and ET‐1 levels in subjects with HSP (correlation coefficient [r] = 0.5254, p < 0.01). These results suggest that levels of IL‐18 and ET‐1 are worth monitoring during the clinical course of the disease, but caution must be exercised in extrapolating data based on small study samples. 相似文献
65.
Disrupted in schizophrenia 1 (DISC1) is well established as a genetic risk factor across a spectrum of psychiatric disorders, a role supported by a growing body of biological studies, making the DISC1 protein interaction network an attractive therapeutic target. By contrast, there is a relative deficit of structural information to relate to the myriad biological functions of DISC1. Here, we critically appraise the available bioinformatics and biochemical analyses on DISC1 and key interacting proteins, and integrate this with the genetic and biological data. We review, analyze, and make predictions regarding the secondary structure and propensity for disordered regions within DISC1, its protein-interaction domains, subcellular localization motifs, and the structural and functional implications of common and ultrarare DISC1 variants associated with major mental illness. We discuss signaling pathways of high pharmacological potential wherein DISC1 participates, including those involving phosphodiesterase 4 (PDE4) and glycogen synthase kinase 3 (GSK3). These predictions and priority areas can inform future research in the translational and potentially guide the therapeutic processes. 相似文献
66.
Dinesh Bhugra MB BS Mrcpsych Christine Cordle MSC Dippsychol 《Sexual and Relationship Therapy》2013,28(1):71-76
Thirty-one Asian clients referred to a well-established sexual dysfunction clinic between 1981 and 1985 were matched for age and sex with 31 non-Asian clients referred in the same period. These two groups were compared on a number of characteristics including type of presenting problem, marital status, referral source and therapy outcome. The findings are discussed in the light of differing sexual mores between the two cultures. 相似文献
67.
68.
69.
Duggal P Haque R Roy S Mondal D Sack RB Farr BM Beaty TH Petri WA 《The Journal of infectious diseases》2004,189(3):520-526
BACKGROUND: The association of antibody responses with both innate and acquired immunity to amebiasis indicate that CD4+ T cells play a role in protection against Entamoeba histolytica infection. To test this hypothesis, we compared the genotype frequencies of human leukocyte antigen (HLA) class II alleles in a cohort of Bangladeshi children intensively monitored for E. histolytica infection for a 3-year period. METHODS: Using logistic regression, we calculated the odds of disease by genotype and by haplotype. RESULTS: The DQB1*0601 heterozygous and homozygous genotypes were found in 55% of E. histolytica-negative children but in only 34% of E. histolytica-positive children (overall odds ratio, 2.39; 95% confidence interval [CI], 1.26-4.54). Children who were heterozygous for the DQB1*0601/DRB1*1501 haplotype were 10.1 times (95% CI, 2.02-50.6) more likely to be both E. histolytica negative and serum anti-lectin immunoglobulin G negative at baseline. Other DQB1 and DRB1 alleles (DQB1*0202, DQB1*0301, and DRB1*0701) were not associated with any of the clinical outcomes related to amebiasis. CONCLUSION: A potential protective association was observed with the HLA class II allele DQB1*0601 and the heterozygous haplotype DQB1*0601/DRB1*1501. This association may explain why amebiasis does not occur in some children who are exposed to the parasite and implicates HLA class II-restricted immune responses in protection against E. histolytica infection. 相似文献
70.
Regulation of 25-hydroxyvitamin D3-1 alpha-hydroxylase and production of 1 alpha,25-dihydroxyvitamin D3 by human dendritic cells 下载免费PDF全文
25-Hydroxyvitamin D3-1 alpha-hydroxylase (25(OH)D3-1 alpha-hydroxylase), the key enzyme of 1 alpha,25-dihydroxyvitamin D3 (1,25(OH)2D3) production, is expressed in monocyte-derived macrophages (MACs). Here we show for the first time constitutive expression of 25(OH)D3-1 alpha-hydroxylase in monocyte-derived dendritic cells (DCs), which was increased after stimulation with lipopolysaccharide (LPS). Accordingly, DCs showed low constitutive production of 1,25(OH)2D3, but activation by LPS increased 1,25(OH)2D3 synthesis. In addition, 25(OH)D3-1 alpha-hydroxylase expression was found in blood DCs but not in CD34+-derived DCs. Next we analyzed the functional consequences of these results. Addition of 1,25(OH)2D3 at concentrations comparable with those produced by DCs inhibited the allostimulatory potential of DCs during the early phase of DC differentiation. However, terminal differentiation decreased the responsiveness of DCs to 1,25(OH)2D3. In conclusion, DCs are able to produce 1,25(OH)2D3 especially following stimulation with LPS. Terminal maturation renders DCs unresponsive to the effects of 1,25(OH)2D3, but those cells are able to suppress the differentiation of their own precursor cells in a paracrine way through the production of 1,25(OH)2D3. 相似文献