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   222405篇
  免费   4521篇
  国内免费   175篇
耳鼻咽喉   1500篇
儿科学   8405篇
妇产科学   4451篇
基础医学   23037篇
口腔科学   2212篇
临床医学   18324篇
内科学   39741篇
皮肤病学   1746篇
神经病学   21356篇
特种医学   10006篇
外科学   33448篇
综合类   2755篇
一般理论   39篇
预防医学   23431篇
眼科学   3671篇
药学   12238篇
  1篇
中国医学   698篇
肿瘤学   20042篇
  2024年   48篇
  2023年   448篇
  2022年   669篇
  2021年   1595篇
  2020年   1034篇
  2019年   1533篇
  2018年   23420篇
  2017年   18376篇
  2016年   20698篇
  2015年   2383篇
  2014年   2781篇
  2013年   3593篇
  2012年   11070篇
  2011年   24976篇
  2010年   20861篇
  2009年   13362篇
  2008年   22524篇
  2007年   24887篇
  2006年   3724篇
  2005年   5146篇
  2004年   5992篇
  2003年   6752篇
  2002年   4790篇
  2001年   562篇
  2000年   614篇
  1999年   442篇
  1998年   613篇
  1997年   580篇
  1996年   360篇
  1995年   335篇
  1994年   293篇
  1993年   297篇
  1992年   181篇
  1991年   195篇
  1990年   208篇
  1989年   157篇
  1988年   134篇
  1987年   84篇
  1986年   84篇
  1985年   84篇
  1984年   89篇
  1983年   88篇
  1982年   99篇
  1981年   56篇
  1980年   100篇
  1979年   43篇
  1978年   54篇
  1938年   62篇
  1932年   57篇
  1930年   46篇
排序方式: 共有10000条查询结果,搜索用时 453 毫秒
41.
The use of livers from anti-hepatitis B core (HBc) positive donors can alleviate donor shortage. Nineteen of 367 (6%) adults receiving anti-HBc positive allografts [three were hepatitis B antigen (HBsAg) negative, hepatitis B antibody (HBsAb) positive; four were HBsAg positive and 12 were not exposed to hepatitis B viral (HBV) infection] were retrospectively reviewed. In HBsAg negative recipients, immunoprophylaxis (IP) was guided by viral serology and immunohistochemistry (IH) of day 0 and day 7 liver biopsies. If IH was negative, IP was stopped. None of three HBsAg negative, HBsAb positive recipients infected; one (replicating) of four HBsAg positive recipients reinfected and seven of eight (87.5%) HBsAg, HBsAb negative recipients, who did not receive long-term IP, infected after a median time of 2 years (range 1-5); one patient died of liver failure. Four HBsAg, HBsAb negative recipients, receiving life-long IP, remained infection free. Anti-HBc positive donor livers must be directed selectively first to HBsAg positive recipients, next to recipients having HBV antibodies and finally to HBV-naive recipients. Identification of both donor and recipient risk factors for HBV infection before transplantation allows indiscriminate use of antiviral prophylaxis. The necessity for IP therapy should be guided by HBV-DNA testing of donor liver tissue and serum. IH of early liver biopsies is an unreliable marker for predicting antiviral treatment requirements.  相似文献   
42.
43.
44.
45.
46.
47.
OBJECTIVE: Respiratory muscle endurance of able-bodied persons, assessed by normocapnic hyperpnoea at 70% of their maximal voluntary ventilation, usually ranges from 10 to 20 minutes. The aim of this study was to determine the level of ventilation that patients with paraplegia and tetraplegia can sustain for 10-20 minutes to later be used as the guideline for respiratory muscle endurance training. DESIGN: Pilot study; cross-over setting. SUBJECTS: Two groups, 8 patients with paraplegia and 6 with tetraplegia. METHODS: Respiratory muscle endurance tests were performed at 3 different intensities of normocapnic hyperpnoea, i.e. 20%, 40% and 60% maximal voluntary ventilation. Subjects performed partial re-breathing from a bag to assure normocapnia. Respiratory endurance was separately analysed for patients with paraplegia and tetraplegia. RESULTS: Mean respiratory endurance times were 46.0, 18.9 and 4.2 minutes at 20%, 40% and 60% maximal voluntary ventilation in patients with tetraplegia and 51.8, 38.8 and 12.2 minutes in patients with paraplegia. The duration differed significantly at 60% maximal voluntary ventilation between the groups. CONCLUSION: Minute ventilation to perform respiratory muscle endurance training can be set at around 40% of maximal voluntary ventilation for patients with tetraplegia and around 60% of maximal voluntary ventilation for patients with paraplegia, as these levels can be sustained for 10-20 minutes.  相似文献   
48.
Campath-1H (alemtuzumab) induction was used for renal transplantation in combination with sirolimus as immunosuppression. We previously reported a high (28%) rate of early rejection with this regimen, and now report 3-year outcomes. Twenty-nine patients were recipients of either deceased donor or non-HLA (Human Leukocyte Antigen) identical living donor primary renal allografts. Clinical parameters including infection, malignancy, kidney function, and kidney histology were followed prospectively for 3 years. Three-year cumulative graft and patient survival were 96% and 100%, respectively. Twenty patients were maintained on steroid-free immunosuppressive regimens, and 15 patients were maintained on monotherapy for immunosuppression (12 on sirolimus). No serious infectious complications were observed and two patients developed basal cell skin cancer. The 3-year results of our initial pilot study demonstrate good graft (96%) and patient (100%) outcomes. Campath-1H induction has yielded a high proportion of patients maintained on immunosuppressive monotherapy (57%) without serious infectious- and no malignancy-related complications. The reported regimen yielded novel insights into both Campath-1H and sirolimus therapy in renal transplantation. Because of the higher incidence of early rejection, we recommend a modified strategy of immunosuppression including a brief course of a calcineurin inhibitor.  相似文献   
49.
Anliegen dieses Artikels ist, die besondere Qualit?t und Chance von Psychodramatischer Supervision zu beschreiben, und gleichzeitig die Kompatibilit?t und fruchtbare Erg?nzung des Moreno’schen Ansatzes innerhalb des Formats Supervision innerhalb der Sozialen Arbeit auf zuzeigen. Dies wird anhand von 2 ausgew?hlten Praxisbeispielen dargestellt. Die Handlungskompetenz von Supervisandinnen und Supervisanden kann durch einfache psychodramatische Interventionen erweitert werden. Handlungshemmung wird überwunden, Spontaneit?t und Kreativit?t kommen ins Laufen und er?ffnen Perspektiven.  相似文献   
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