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   12872篇
  免费   572篇
  国内免费   22篇
耳鼻咽喉   364篇
儿科学   398篇
妇产科学   452篇
基础医学   1021篇
口腔科学   207篇
临床医学   1070篇
内科学   2693篇
皮肤病学   449篇
神经病学   681篇
特种医学   692篇
外科学   2815篇
综合类   59篇
一般理论   1篇
预防医学   673篇
眼科学   430篇
药学   648篇
中国医学   53篇
肿瘤学   760篇
  2024年   13篇
  2023年   92篇
  2022年   219篇
  2021年   348篇
  2020年   200篇
  2019年   236篇
  2018年   286篇
  2017年   194篇
  2016年   207篇
  2015年   698篇
  2014年   818篇
  2013年   874篇
  2012年   998篇
  2011年   923篇
  2010年   796篇
  2009年   755篇
  2008年   888篇
  2007年   826篇
  2006年   766篇
  2005年   702篇
  2004年   506篇
  2003年   298篇
  2002年   227篇
  2001年   170篇
  2000年   157篇
  1999年   162篇
  1998年   82篇
  1997年   101篇
  1996年   80篇
  1995年   48篇
  1994年   44篇
  1993年   43篇
  1992年   63篇
  1991年   62篇
  1990年   70篇
  1989年   54篇
  1988年   40篇
  1987年   41篇
  1986年   36篇
  1985年   31篇
  1984年   34篇
  1983年   39篇
  1982年   33篇
  1981年   32篇
  1980年   26篇
  1979年   27篇
  1978年   14篇
  1977年   14篇
  1976年   14篇
  1973年   13篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
5.
Chronic transplant dysfunction is a complex dynamic pathogenic process. Clinically, a decrease in glomerular filtration rate (GFR) becomes apparent leading to chronic renal insufficiency and dialysis or death from cardiovascular events. Chronic transplant dysfunction can develop into a chronic alIograft nephropathy (CAN) as a specific entity with dynamic progression. CAN includes a collection of immunologic and non-immunologic factors, rejection, ischemia time, donor and recipient characteristics and toxicity of calcineurin inhibitors. Despite improvements in immunosuppression, the long-range prognosis of renal allografts has not improved. Whether modern immunosuppressive concepts with reduction or avoidance of calcineurin inhibitors and a therapy based on antimetabolites, such as mycophenolate or mTOR-inhibitors could lead to a prolongation of transplant survival, remains to be seen.  相似文献   
6.
7.
8.
Choledochojejunostomy (CJS) is commonly used for biliary reconstruction in liver transplantation for primary sclerosing cholangitis (PSC). We alternatively performed choledochoduodenostomy (CDS) and side-to-side choledochodocholedochstomy in a large cohort of patients. Fifty-one patients with PSC, transplanted between 1988 and 2000, were analyzed retrospectively. Biliary reconstruction was CDS in 25 (49%), CJS in 20 (39%) and CC in 6 transplantations (12%). Biliary leaks occurred in the early follow-up (< or =41 days) only in CDS patients (20%). However, in the late follow-up (>4 months), stricturing of anastomosis was found once in CDS (4%) and CJS (5%). Later (>9 months), intrahepatic bile duct strictures were diagnosed in four CDS (16%), one CJS (5%) and one CC (17%) patient(s). In 48% of CDS (12/25), 60% of CJS (12/20) and 17% of CC (1/6) at least one incidence of cholangitis was observed. Overall, biliary complication rates were significantly higher in CDS (40%) than CJS (10%) and CC (17%); of those none in CC and 12% in CDS were anastomosis-related. Graft/patient survival showed no significant differences among groups. Based on our results we consider CJS the standard method for biliary reconstruction in PSC; however, in selected cases where CJS is difficult to accomplish because of previous surgery or for retransplantation, CDS may present an alternative technique.  相似文献   
9.
BACKGROUND & AIMS: Many patients with chronic hepatitis C virus (HCV) have persistently normal serum alanine transaminase (ALT) levels. We compared characteristics of chronic hepatitis C patients with patients with normal and elevated ALT levels using data from 3 randomized phase III trials of peginterferon alfa-2a (40 kDa). METHODS: The characteristics of 480 patients with normal ALT values (on >or=3 occasions without any increases in ALT level over a 6- to 18-month period) and 1993 patients with elevated ALT levels were compared. Sixty-eight of the 480 patients with normal ALT levels were randomized to no treatment and monitored for 72 weeks. RESULTS: More patients with normal ALT levels than patients with elevated ALT levels were women (59% vs 32%; P<.01). The serum HCV RNA titer was significantly lower in patients with normal ALT levels (P<.01 vs in patients with elevated ALT levels). Patients with normal ALT levels had significantly lower inflammation and fibrosis scores on liver biopsy examination than patients with elevated ALT levels, but almost two-thirds had portal fibrosis and 10% had bridging fibrosis. No correlation between baseline ALT activity, HCV RNA level, and liver histology was observed in patients with normal ALT levels. During the 72-week follow-up period, ALT activity elevated above the upper limit of normal in 53% of the untreated patients with normal levels of ALT. None became HCV RNA undetectable. CONCLUSIONS: Chronic hepatitis C patients with normal ALT levels should be evaluated in a similar manner as patients with elevated ALT levels because they are at risk for developing significant liver disease. The decision to treat with peginterferon alfa and ribavirin should be based on multiple factors, rather than on ALT levels alone.  相似文献   
10.
In chronic pain syndromes multimodal treatment has proved its efficacy. However, multimodal treatment does not mean randomly combining different interventions in a potpourri of methods. Multimodal treatment must closely follow a well-proved conceptual framework. Those concepts may be well illustrated by therapy of back pain. The most elaborate model for understanding the transition from acute to chronic pain is fear avoidance. Based on this model chronic pain status is understood as a learned consequence, which resulted from patients’ anxious avoidance of body movements. In these cases, treatment of a physical pathology is not the main aim of therapy but rather functional restoration. Those multimodal programs meanwhile have demonstrated their effectiveness. However, good results not only depend on recognition of imperative elements in therapy but also on adhering to essential principles (avoidance of negative anticipation, adequate information with assurance techniques, no training of avoidance, recognition of elements of fear therapy).  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