全文获取类型
收费全文 | 19417篇 |
免费 | 974篇 |
国内免费 | 55篇 |
专业分类
耳鼻咽喉 | 264篇 |
儿科学 | 520篇 |
妇产科学 | 271篇 |
基础医学 | 2802篇 |
口腔科学 | 881篇 |
临床医学 | 1416篇 |
内科学 | 4180篇 |
皮肤病学 | 369篇 |
神经病学 | 1787篇 |
特种医学 | 537篇 |
外国民族医学 | 2篇 |
外科学 | 2609篇 |
综合类 | 62篇 |
一般理论 | 4篇 |
预防医学 | 1714篇 |
眼科学 | 410篇 |
药学 | 1281篇 |
中国医学 | 62篇 |
肿瘤学 | 1275篇 |
出版年
2023年 | 147篇 |
2022年 | 108篇 |
2021年 | 312篇 |
2020年 | 224篇 |
2019年 | 298篇 |
2018年 | 725篇 |
2017年 | 475篇 |
2016年 | 478篇 |
2015年 | 620篇 |
2014年 | 614篇 |
2013年 | 911篇 |
2012年 | 1580篇 |
2011年 | 1625篇 |
2010年 | 816篇 |
2009年 | 561篇 |
2008年 | 1459篇 |
2007年 | 1430篇 |
2006年 | 1370篇 |
2005年 | 1298篇 |
2004年 | 1233篇 |
2003年 | 1092篇 |
2002年 | 1007篇 |
2001年 | 212篇 |
2000年 | 218篇 |
1999年 | 180篇 |
1998年 | 73篇 |
1997年 | 61篇 |
1996年 | 49篇 |
1995年 | 50篇 |
1994年 | 32篇 |
1993年 | 40篇 |
1992年 | 102篇 |
1991年 | 89篇 |
1990年 | 80篇 |
1989年 | 65篇 |
1988年 | 46篇 |
1987年 | 51篇 |
1986年 | 54篇 |
1985年 | 54篇 |
1984年 | 63篇 |
1983年 | 43篇 |
1982年 | 53篇 |
1981年 | 32篇 |
1980年 | 43篇 |
1979年 | 37篇 |
1978年 | 31篇 |
1977年 | 22篇 |
1976年 | 31篇 |
1973年 | 30篇 |
1971年 | 21篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
Jose M. Morales Jose Angel Martinez-Flores Manuel Serrano Maria José Castro Francisco Javier Alfaro Florencio García Miguel Angel Martínez Amado Andrés Esther González Manuel Praga Estela Paz-Artal Antonio Serrano 《Journal of the American Society of Nephrology : JASN》2015,26(3):735-745
In the current immunosuppressive therapy era, vessel thrombosis is the most common cause of early graft loss after renal transplantation. The prevalence of IgA anti–β2-glycoprotein I antibodies (IgA-aB2GPI-ab) in patients on dialysis is elevated (>30%), and these antibodies correlate with mortality and cardiovascular morbidity. To evaluate the effect of IgA-aB2GPI-ab in patients with transplants, we followed all patients transplanted from 2000 to 2002 in the Hospital 12 de Octubre prospectively for 10 years. Presence of IgA-aB2GPI-ab in pretransplant serum was examined retrospectively. Of 269 patients, 89 patients were positive for IgA-aB2GPI-ab (33%; group 1), and the remaining patients were negative (67%; group 2). Graft loss at 6 months post-transplant was significantly higher in group 1 (10 of 89 versus 3 of 180 patients in group 2; P=0.002). The most frequent cause of graft loss was thrombosis of the vessels, which was observed only in group 1 (8 of 10 versus 0 of 3 patients in group 2; P=0.04). Multivariate analysis showed that the presence of IgA-aB2GPI-ab was an independent risk factor for early graft loss (P=0.04) and delayed graft function (P=0.04). There were no significant differences regarding patient survival between the two groups. Graft survival was similar in both groups after 6 months. In conclusion, patients with pretransplant IgA-aB2GPI-ab have a high risk of early graft loss caused by thrombosis and a high risk of delayed graft function. Therefore, pretransplant IgA-aB2GPI-ab may have a detrimental effect on early clinical outcomes after renal transplantation. 相似文献
2.
3.
Talita da Silva Mendes de Farias Ariclécio Cunha de Oliveira Sandra Andreotti Fernanda Gaspar do Amaral Patrícia Chimin André Ricardo Alves de Proença Francisco Leonardo Torres Leal Rogério Antonio Laurato Sertié Amanda Baron Campana Andressa Bolsoni Lopes Arnaldo Henrique de Souza José Cipolla‐Neto Fabio Bessa Lima 《Journal of pineal research》2015,58(3):251-261
Melatonin, the main hormone produced by the pineal gland, is secreted in a circadian manner (24‐hr period), and its oscillation influences several circadian biological rhythms, such as the regulation of clock genes expression (chronobiotic effect) and the modulation of several endocrine functions in peripheral tissues. Assuming that the circadian synchronization of clock genes can play a role in the regulation of energy metabolism and it is influenced by melatonin, our study was designed to assess possible alterations as a consequence of melatonin absence on the circadian expression of clock genes in the epididymal adipose tissue of male Wistar rats and the possible metabolic repercussions to this tissue. Our data show that pinealectomy indeed has impacts on molecular events: it abolishes the daily pattern of the expression of Clock, Per2, and Cry1 clock genes and Pparγ expression, significantly increases the amplitude of daily expression of Rev‐erbα, and affects the pattern of and impairs adipokine production, leading to a decrease in leptin levels. However, regarding some metabolic aspects of adipocyte functions, such as its ability to synthesize triacylglycerols from glucose along 24 hr, was not compromised by pinealectomy, although the daily profile of the lipogenic enzymes expression (ATP‐citrate lyase, malic enzyme, fatty acid synthase, and glucose‐6‐phosphate dehydrogenase) was abolished in pinealectomized animals. 相似文献
4.
José A. Lorente Pablo Cardinal-Fernández Diego Muñoz Fernando Frutos-Vivar Arnaud W. Thille Carlos Jaramillo Aida Ballén-Barragán José M. Rodríguez Oscar Peñuelas Guillermo Ortiz José Blanco Bruno Valle Pinheiro Nicolás Nin María del Carmen Marin Andrés Esteban Taylor B. Thompson 《Intensive care medicine》2015,41(11):1921-1930
5.
BMP-2 gene polymorphisms and osteoporosis: the Rotterdam Study. 总被引:7,自引:0,他引:7
Marco Medici Joyce Bj van Meurs Fernando Rivadeneira HongYan Zhao Pascal P Arp Albert Hofman Huibert Ap Pols André G Uitterlinden 《Journal of bone and mineral research》2006,21(6):845-854
After reported associations of variations in the BMP-2 gene with osteoporosis in small populations, we studied the association of the BMP-2 gene polymorphisms Ser37Ala and Arg190Ser with osteoporosis in 6353 men and women from the Rotterdam Study. We did not observe an association of these variants with BMD, bone loss, hip structural analysis parameters, and fracture risk. INTRODUCTION: Bone morphogenetic protein 2 (BMP-2) plays a role in osteoblast differentiation. BMP-2 gene variation has previously been associated with osteoporosis in various small populations, but current evidence remains inconclusive about the exact association with osteoporosis. Therefore, we studied the association of two polymorphisms located in the BMP-2 gene (Ser37Ala and Arg190Ser) and haplotypes defined by these polymorphisms with BMD, rates of bone loss, parameters of hip structural analysis (HSA), and fractures in the Rotterdam Study, a large prospective cohort study of diseases in the elderly. MATERIALS AND METHODS: Databases were searched for polymorphisms and haplotype blocks in the BMP-2 gene region. Allele frequencies for Ser37Ala and Arg190Ser were determined in 60 blacks and 110 Chinese from Coriell panels. Genotype data on Ser37Ala and Arg190Ser were available for 6353 individuals from the Rotterdam Study population. Haplotype alleles defined by Ser37Ala and Arg190Ser were inferred using PHASE software. Genotype and haplotype analyses for BMD (measured at the lumbar spine and femoral neck), bone loss per year (measured at the femoral neck), and HSA were performed using AN(C)OVA. Fractures were analyzed using a Cox proportional-hazards model and logistic regression. All outcomes were adjusted for age, height, and weight. RESULTS: Allele frequencies were 2.5% for Ala37 and 40.2% for Ser190, whereas haplotype allele frequencies were 57.28% (Ser37Arg190), 40.19% (Ser37Ser190), 2.50% (Ala37Arg190), and 0.02% (Ala37Ser190). For BMD, bone loss, HSA outcomes, and (incident) fractures, no differences could be seen between genotype and haplotype groups. Conclusions: In this large population-based cohort of Dutch whites, we conclude that the BMP-2 Ser37Ala and Arg190Ser polymorphisms or haplotypes thereof are not associated with parameters of osteoporosis. 相似文献
6.
7.
8.
9.
Long-term effects of physical exercise on working capacity and pulmonary function in cystic fibrosis 总被引:1,自引:0,他引:1
B Andréasson B Jonson R Kornf?lt E Nordmark S Sandstr?m 《Acta paediatrica Scandinavica》1987,76(1):70-75
Seven patients with cystic fibrosis aged 6 to 20 were enrolled for 30 months in a daily exercise program. After 12 months conventional chest physiotherapy was withdrawn. Patients with low initial Shwachman scores improved as regards maximal working capacity. Spirometric data and volume of trapped gas indicated opening of closed airways. We suggest that physical exercise in general should be the basis of pulmonary therapy in cystic fibrosis. Other forms of physiotherapy are advisable when hard physical exercise is not feasible. 相似文献
10.