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   13308篇
  免费   764篇
  国内免费   21篇
耳鼻咽喉   151篇
儿科学   405篇
妇产科学   367篇
基础医学   1557篇
口腔科学   154篇
临床医学   2232篇
内科学   2040篇
皮肤病学   203篇
神经病学   1229篇
特种医学   279篇
外科学   1248篇
综合类   230篇
一般理论   24篇
预防医学   1518篇
眼科学   629篇
药学   836篇
  2篇
中国医学   7篇
肿瘤学   982篇
  2023年   58篇
  2022年   127篇
  2021年   216篇
  2020年   145篇
  2019年   238篇
  2018年   261篇
  2017年   206篇
  2016年   204篇
  2015年   233篇
  2014年   320篇
  2013年   582篇
  2012年   775篇
  2011年   926篇
  2010年   496篇
  2009年   455篇
  2008年   817篇
  2007年   817篇
  2006年   885篇
  2005年   871篇
  2004年   972篇
  2003年   969篇
  2002年   808篇
  2001年   243篇
  2000年   114篇
  1999年   140篇
  1998年   180篇
  1997年   171篇
  1996年   99篇
  1995年   109篇
  1994年   75篇
  1993年   80篇
  1992年   106篇
  1991年   79篇
  1990年   85篇
  1989年   75篇
  1988年   64篇
  1987年   69篇
  1986年   80篇
  1985年   67篇
  1984年   68篇
  1983年   72篇
  1982年   58篇
  1981年   67篇
  1980年   76篇
  1979年   44篇
  1978年   47篇
  1977年   38篇
  1975年   36篇
  1973年   41篇
  1972年   35篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
12.
13.
14.
15.
The anaesthetic management of children with glycogen-storage disease type lia (Pompe’s disease) presents a variety of challenges. A modification of a femoral nerve block, the inguinal paravascular block, as described by Winnie, was used in conjunction with intravenous ketamine to provide anaesthesia for a diagnostic muscle biopsy in a 5.5-month-old infant with Pompe’s disease. A peripheral nerve stimulator was used to locate the femoral nerve in lieu of eliciting a paraesthesia.  相似文献   
16.
Median nerves of rats were reconstructed with conventional or vascular nerve grafts. After 2, 3 and 4 weeks, Allen Video-Enhanced Contrast, Differential Interference Contrast (AVEC-DIC) microscopy revealed axonal transport in most preparations, with varying degrees of myelination. Radio-isotope tracer was measured in the nerve. Two and 4 week measurements revealed no difference between the graft types. At 3 weeks the vascular graft group exhibited transport along the entire length of the nerve in contrast to a relatively abbreviated path length in the conventional graft group. Nerve conduction velocities (NCV) were measured proximal to, within and distal to the grafts. Three week NCV showed no difference between the graft types. The 4 week NCV revealed normal values in the vascular graft group at points distal to and within the graft. Significant slowing was seen in the conventional grafts at both points.  相似文献   
17.
OBJECTIVE: Non-steroidal anti-inflammatory drugs (NSAIDs) are routinely used after coronary artery bypass surgery (CABG), yet their effects have seldom been evaluated in randomized controlled settings. The aim of this study was to examine the efficacy and safety of a commonly used NSAID, naproxen. We hypothesized that naproxen would reduce postoperative pain following CABG without increasing complications. METHODS: Patients (N=98) undergoing primary CABG were randomized to receive naproxen (500 mg q12hX5 doses via suppository started 1h after operation, followed by oral 250 mg q8hX6 doses) or placebo. Standard analgesic and anti-emetic regimens were available to both patient groups. Interventions were double-blinded. Primary end-points were postoperative pain measured before and after chest physiotherapy by visual analog scale and pulmonary slow vital capacity (SVC). RESULTS: Baseline characteristics were equivalent between the two groups. Over the first 4 postoperative days, naproxen decreased pain by 47+/-17% on average before chest physiotherapy (P=0.034), and 44+/-13% after chest physiotherapy (P=0.0092). Patients who received naproxen also had better preservation of SVC over the first 4 postoperative days (mean loss of SVC from baseline: 2.1+/-0.1 vs. 2.5+/-0.1l, naproxen vs. placebo, P=0.0032). This was concomitant with a lower white blood cell count observed in naproxen patients (9.2+/-0.3 vs. 12.7+/-1.5x10(9)/l, naproxen vs. placebo, P=0.03). Patients who received naproxen had more chest tube drainage after 4h postoperatively, but there was no difference in the incidence or amount of transfusions. There was no difference in medication use, length of stay, or in the incidence of atrial fibrillation, azotemia, and other complications. CONCLUSIONS: Naproxen is an effective and low-cost adjunct for optimization of pain control and lung recovery after CABG. Its use may result in increased chest tube drainage, but no apparent increase in other complications.  相似文献   
18.
Recurrent pleural effusions are common complications of hospitalized patients with human immunodeficiency virus (HIV) infection and may pose difficult diagnostic dilemmas. A common cause of recurrent pleural effusions in up to 30% of HIV-seropositive patients is pulmonary involvement by Kaposi's sarcoma, a human herpesvirus 8 (HHV 8)-related neoplasm. The pathogenesis of these effusions is unclear. These recurrent effusions, although benign, have shown significant mesothelial atypia/reactive changes of uncertain etiology. We attempted to evaluate these effusions morphologically and molecularly for the presence of HHV 8, with particular attention to mesothelial cells. All recurrent pleural effusions, as defined by any effusion tapped for cytological examination on more than two occasions, in HIV-positive patients at the National Institutes of Health were examined from 1998 to the present. Cases were stratified according to patients with and without histologically confirmed HHV 8 disease manifestations. Five patients with HHV 8 diseases (four with disseminated Kaposi's sarcoma and one with Castleman's disease) were identified. As a control group, five effusions from HIV-seropositive patients without known HHV 8-related diseases were identified. Cytological examination of effusions in patients with HHV 8-related diseases demonstrated atypical/markedly reactive mesothelial cells accompanied by a polymorphous background of lymphocytes. Molecular studies for B- and T-cell clonality in microdissected whole samples showed no definitive clones in these cases. Conversely, polymerase chain reaction (PCR) studies for the HHV 8 virus was positive in these samples. PCR studies on pure populations of microdissected mesothelial cells from the HHV 8-related effusions were positive for HHV 8 sequences, whereas those from HIV patients with non-HHV 8 related diseases were negative. Immunohistochemistry for HHV 8 (monoclonal antibody to latent nuclear antigen (LNA-1; ORF-73) on cellblock material demonstrated scattered positive mesothelial cells in three of the five cases of HHV 8-associated effusions. HHV 8 has been recently implicated in the pathogenesis of Kaposi's sarcoma and primary effusion lymphoma. Mesothelial cells in recurrent pleural effusions from patients with Kaposi's sarcoma and Castleman's disease appear to be infected with HHV 8. Additional studies need to be done to define the role of mesothelial cell infection in the pathogenesis of these HHV 8-associated effusions and define the prognostic significance.  相似文献   
19.
20.
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