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   3242篇
  免费   206篇
  国内免费   80篇
耳鼻咽喉   5篇
儿科学   193篇
妇产科学   50篇
基础医学   360篇
口腔科学   72篇
临床医学   359篇
内科学   733篇
皮肤病学   82篇
神经病学   167篇
特种医学   411篇
外科学   433篇
综合类   47篇
预防医学   221篇
眼科学   27篇
药学   216篇
  2篇
肿瘤学   150篇
  2022年   21篇
  2021年   39篇
  2020年   30篇
  2019年   32篇
  2018年   47篇
  2017年   47篇
  2016年   37篇
  2015年   59篇
  2014年   88篇
  2013年   99篇
  2012年   99篇
  2011年   89篇
  2010年   117篇
  2009年   125篇
  2008年   103篇
  2007年   124篇
  2006年   85篇
  2005年   108篇
  2004年   54篇
  2003年   86篇
  2002年   60篇
  2001年   71篇
  2000年   84篇
  1999年   66篇
  1998年   141篇
  1997年   169篇
  1996年   143篇
  1995年   119篇
  1994年   125篇
  1993年   104篇
  1992年   44篇
  1991年   64篇
  1990年   59篇
  1989年   79篇
  1988年   67篇
  1987年   69篇
  1986年   77篇
  1985年   63篇
  1984年   49篇
  1983年   27篇
  1982年   37篇
  1981年   36篇
  1980年   42篇
  1979年   13篇
  1978年   17篇
  1977年   27篇
  1976年   33篇
  1975年   24篇
  1971年   16篇
  1967年   11篇
排序方式: 共有3528条查询结果,搜索用时 15 毫秒
1.
Cutaneous plasmacytosis is a rare disorder characterized by a benign proliferation of mature plasma cells that appears as multiple dark-brown to purplish skin lesions, often associated with polyclonal hypergammaglobulinaemia. We present the case of a 55-year-old Caucasian man who suffered from a cutaneous plasmacytosis associated with two different carcinomas. Cutaneous plasmacytosis seems to be a reactive process because most cases reported are not associated with any apparent underlying disease. Nevertheless, because few reported cases were associated with malignancies, screening of additional neoplasms would be justified.  相似文献   
2.
Two patients with a history of glaucoma and a propensity for uveitis developed ciliochoroidal effusions following Nd:YAG laser posterior capsulotomy. Both patients experienced a waxing and waning course with eventual resolution of symptoms after a steroid regimen. The ciliochoroidal effusions were presumed to be secondary to uveitis induced by the YAG laser surgery. The role of glaucoma, previous surgeries, and an open posterior capsule is uncertain but may have predisposed these patients to ciliochoroidal detachment. We advise caution in performing YAG posterior capsulotomy in patients with glaucoma and a known propensity for uveitis.  相似文献   
3.
The aim of this study was to evaluate the cerebral synthesis of eicosanoids in the asphyctic newborn and to investigate the relation between the prostanoid profiles in cerebrospinal fluid (CSF) and the appearance and severity of hypoxic-ischaemic encephalopathy (HIE). Levels of 6-keto-PGF 1-α, TXB2, PGE2 and PGF2-α in CSF were measured in 40 full term newborns during the first day of life. Thirty of these newborns had birth asphyxia and were divided into three groups: 10 without HIE, 12 with mild HIE and 8 with moderate-severe HIE. They were compared to a control group of 10 non-hypoxic newborns. Determinations of the metabolites in CSF were performed by RIA and expressed as pg/ml (mean ± SD). The CSF TXB2 (thromboxane A2 metabolite) in asphyxiated newborns was always higher than in the control group (28.12 ± 10.6), and related to the severity of HIE ( p = 0:005): without HIE (50.84 ± 16.4; p = 0:02), mild HIE (80.65 ± 12.64; p ± 0:01) and moderate-severe HIE (178.14 ± 20.5; p < 0:01). The CSF 6-keto-PGF 1-α (prostacyclin metabolite) in asphyxiated newborns was always higher than in the control group (80.55 ± 12.56), but indirectly related to the severity of HIE: without HIE (240.95 ± 28.12; p < 0:01), mild HIE (183.65 ± 30.1; p < 0:01) and moderate-severe HIE (140.55 ± 25.12; p < 0:01). In the moderate-severe HIE group, the increase in TXB2 was higher than the rise in 6-keto-PGF 1-α.  相似文献   
4.
5.
6.
7.
8.
9.
10.
FM sonography - a signal-processing technique that uses frequency and phase information as well as amplitude data - shows promise in evaluation of patients with diffuse liver disease. In a prospective blinded review of 37 patients with biopsy-proved liver disease and 42 healthy volunteers, FM sonography was clearly superior to traditional amplitude-based (AM) sonography in distinguishing healthy from diseased subjects. Statistically significant differences were seen in accuracy (FM, 98.7%; AM, 84.8%), sensitivity (FM, 97.3%; AM, 70.3%), and negative predictive value (FM, 97.7%; AM, 78.8%). Our data also suggest that current FM sonographic techniques cannot differentiate among histologic findings associated with different hepatic parenchymal abnormalities. It is unclear, therefore, whether FM imaging can reduce the numbers of patients who require biopsy for diagnosis or the frequency of biopsy procedures in patients with known disease.  相似文献   
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