首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   356439篇
  免费   33036篇
  国内免费   24033篇
耳鼻咽喉   3307篇
儿科学   4056篇
妇产科学   5427篇
基础医学   42896篇
口腔科学   6154篇
临床医学   49221篇
内科学   54347篇
皮肤病学   3619篇
神经病学   20185篇
特种医学   12931篇
外国民族医学   215篇
外科学   36285篇
综合类   55066篇
现状与发展   91篇
一般理论   44篇
预防医学   23005篇
眼科学   10416篇
药学   36377篇
  384篇
中国医学   19674篇
肿瘤学   29808篇
  2024年   1105篇
  2023年   5419篇
  2022年   14179篇
  2021年   17779篇
  2020年   13294篇
  2019年   11812篇
  2018年   12548篇
  2017年   11072篇
  2016年   10377篇
  2015年   15741篇
  2014年   19470篇
  2013年   17220篇
  2012年   25628篇
  2011年   28706篇
  2010年   18062篇
  2009年   14089篇
  2008年   19289篇
  2007年   19165篇
  2006年   18935篇
  2005年   18460篇
  2004年   11948篇
  2003年   10946篇
  2002年   9416篇
  2001年   7835篇
  2000年   8586篇
  1999年   9238篇
  1998年   5705篇
  1997年   5680篇
  1996年   4458篇
  1995年   4028篇
  1994年   3326篇
  1993年   2179篇
  1992年   2918篇
  1991年   2510篇
  1990年   2190篇
  1989年   1916篇
  1988年   1613篇
  1987年   1352篇
  1986年   1150篇
  1985年   963篇
  1984年   583篇
  1983年   433篇
  1982年   311篇
  1981年   284篇
  1980年   226篇
  1979年   244篇
  1978年   114篇
  1977年   120篇
  1974年   120篇
  1973年   98篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
Caring for patients with end-stage kidney disease (ESKD) in the United States is challenging, due in part to the complex epidemiology of the disease's progression as well as the ways in which care is delivered. As CKD progresses toward ESKD, the number of comorbidities increases and care involves multiple healthcare providers from multiple subspecialties. This occurs in the context of a fragmented US healthcare delivery system that is traditionally siloed by provider specialty, organization, as well as systems of payment and administration. This article describes the role of care fragmentation in the delivery of optimal ESKD care and identifies research gaps in the evidence across the continuum of care. We then consider the impact of care fragmentation on ESKD care from the patient and health system perspectives and explore opportunities for system-level interventions aimed at improving care for patients with ESKD.  相似文献   
42.
AimsWe previously showed that the protective effects of endothelial progenitor cells (EPCs)‐released exosomes (EPC‐EXs) on endothelium in diabetes. However, whether EPC‐EXs are protective in diabetic ischemic stroke is unknown. Here, we investigated the effects of EPC‐EXs on diabetic stroke mice and tested whether miR‐126 enriched EPC‐EXs (EPC‐EXsmiR126) have enhanced efficacy.MethodsThe db/db mice subjected to ischemic stroke were intravenously administrated with EPC‐EXs 2 hours after ischemic stroke. The infarct volume, cerebral microvascular density (MVD), cerebral blood flow (CBF), neurological function, angiogenesis and neurogenesis, and levels of cleaved caspase‐3, miR‐126, and VEGFR2 were measured on day 2 and 14.ResultsWe found that (a) injected EPC‐EXs merged with brain endothelial cells, neurons, astrocytes, and microglia in the peri‐infarct area; (b) EPC‐EXsmiR126 were more effective than EPC‐EXs in decreasing infarct size and increasing CBF and MVD, and in promoting angiogenesis and neurogenesis as well as neurological functional recovery; (c) These effects were accompanied with downregulated cleaved caspase‐3 on day 2 and vascular endothelial growth factor receptor 2 (VEGFR2) upregulation till day 14.ConclusionOur results indicate that enrichment of miR126 enhanced the therapeutic efficacy of EPC‐EXs on diabetic ischemic stroke by attenuating acute injury and promoting neurological function recovery.  相似文献   
43.
44.
利用空间频域成像技术搭建的成像系统检测多种皮肤病组织的光学参数和生理参数信息,并对比分析讨论不同类型的皮肤病与光学参数、生理参数之间的关系。实验结果表明,病变皮肤组织与正常皮肤组织之间在光学参数、生理参数上存在较大差异,这将为临床医生对皮肤病诊治提供一种新颖、可靠、科学的评估方法。  相似文献   
45.
46.
47.
48.
The objective of this study was to investigate short segment decompression of degenerative lumbar scoliosis (DLS) and the efficiency of fusion treatment.After DLS surgery, the patients were retrospectively reviewed using the VAS (visual analog scale) and ODI (Oswestry Disability Index) to assess clinical outcomes. All patients underwent posterior lumbar decompressive laminectomy, pedicle screw internal fixation, and posterolateral bone graft fusion surgery. Radiographic measurements included the scoliotic Cobb angle, the fused Cobb angle, the anterior intervertebral angle (AIA), the sagittal intervertebral angle (SIA), and lumbar lordosis angle. The relationships between these parameters were examined by bivariate Pearson analysis and linear regression analysis.Preoperatively, the Cobb angle at the scoliotic segment was 15.4°, which decreased to 10.2° immediately following surgery (P < 0.05). The AIA significantly increased by the last follow-up (4.4 ± 3.4) compared with pre- and postoperative values (2.5 ± 2.8 and 2.2 ± 2.4, respectively; P < 0.05). However, the scoliotic Cobb angle and the AIA did not correlate with the VAS or ODI scores. At the final follow-up, no patients had pseudoarthrosis or internal instrumentation-related complications.Short fusion surgical treatment results in limited DLS correction, with correction loss over time. The AIA between the upper adjacent segment and proximal fused vertebra continues to increase postoperatively, which does not exacerbate clinical symptoms, as reflected by the low reoperation rates for repairing degeneration at adjacent levels.  相似文献   
49.
50.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号