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   1864篇
  免费   103篇
  国内免费   6篇
耳鼻咽喉   8篇
儿科学   48篇
妇产科学   61篇
基础医学   260篇
口腔科学   30篇
临床医学   165篇
内科学   400篇
皮肤病学   22篇
神经病学   179篇
特种医学   130篇
外科学   289篇
综合类   3篇
预防医学   112篇
眼科学   18篇
药学   124篇
中国医学   1篇
肿瘤学   123篇
  2023年   14篇
  2022年   24篇
  2021年   54篇
  2020年   20篇
  2019年   36篇
  2018年   51篇
  2017年   41篇
  2016年   31篇
  2015年   46篇
  2014年   74篇
  2013年   100篇
  2012年   108篇
  2011年   103篇
  2010年   89篇
  2009年   80篇
  2008年   96篇
  2007年   93篇
  2006年   113篇
  2005年   97篇
  2004年   85篇
  2003年   69篇
  2002年   73篇
  2001年   64篇
  2000年   52篇
  1999年   39篇
  1998年   11篇
  1997年   14篇
  1996年   8篇
  1995年   14篇
  1994年   15篇
  1993年   6篇
  1992年   25篇
  1991年   37篇
  1990年   26篇
  1989年   25篇
  1988年   10篇
  1987年   16篇
  1986年   11篇
  1985年   15篇
  1984年   8篇
  1983年   4篇
  1982年   4篇
  1980年   5篇
  1979年   14篇
  1978年   5篇
  1977年   6篇
  1974年   7篇
  1973年   8篇
  1970年   5篇
  1967年   3篇
排序方式: 共有1973条查询结果,搜索用时 0 毫秒
21.

Background

Although used as criterion for early drain removal, postoperative day (POD) 1 drain fluid amylase (DFA) ≤ 5000 U/L has low negative predictive value for clinically relevant postoperative pancreatic fistula (CR-POPF). It was hypothesized that POD3 DFA ≤ 350 could provide further information to guide early drain removal.

Methods

Data from a pancreas surgery consortium database for pancreatoduodenectomy and distal pancreatectomy patients were analyzed retrospectively. Those patients without drains or POD 1 and 3 DFA data were excluded. Patients with POD1 DFA ≤ 5000 were divided into groups based on POD3 DFA: Group A (≤350) and Group B (>350). Operative characteristics and 60-day outcomes were compared using chi-square test.

Results

Among 687 patients in the database, all data were available for 380. Fifty-five (14.5%) had a POD1 DFA > 5000. Among 325 with POD1 DFA ≤ 5000, 254 (78.2%) were in Group A and 71 (21.8%) in Group B. Complications (35 (49.3%) vs 87 (34.4%); p = 0.021) and CR-POPF (13 (18.3%) vs 10 (3.9%); p < 0.001) were more frequent in Group B.

Conclusions

In patients with POD1 DFA ≤ 5000, POD3 DFA ≤ 350 may be a practical test to guide safe early drain removal. Further prospective testing may be useful.  相似文献   
22.
23.
24.
Interleukin-1 (IL-1) is increased in lung lavages obtained from patients with acute lung injury (ALI) and administering recombinant human IL-1alpha (rhIL-1alpha) (50 ng) intratracheally causes an acute, neutrophil-dependent, oxidative lung leak in rats that closely resembles human ALI. In the present work, the authors tested the hypothesis that transforming growth factor beta (TGFbeta) contributes to the lung inflammation and injury that develops in rats given IL-1 intratracheally. They found that intravenous administration of a monoclonal antibody to TGFbeta (1.D.11.16, 0.5 mg/kg) attenuated lung injury responses, specifically lung leak index, lung lavage protein concentrations, and blood oxygenation abnormalities, that are observed 5 hours after intratracheal instillation of IL-1 in rats, but did not decrease indices of lung inflammation, specifically myeloperoxidase (MPO) activity in lung tissue, neutrophil counts in lung lavage, and cytokine-induced neutrophil chemoattractant (CINC) levels in lung lavage, in rats given IL-1 intratracheally. The results suggest that TGFbeta contributes to lung leak, but not lung inflammation, following intratracheal administration of IL-1 in rats.  相似文献   
25.
BACKGROUND: The authors have previously reported a possible increased risk of the familial occurrence of Crohn's disease in patients with celiac disease. AIM: The aim of the current study was to evaluate in a case-control study the familial occurrence of inflammatory bowel disease (IBD) in first-degree relatives of patients with celiac disease. METHODS: One hundred eleven consecutive patients with biopsy-proven celiac disease were interviewed to ascertain whether IBD was present in first-degree relatives. The number of relatives, their ages, and possible IBD status were collected in a questionnaire. When a diagnosis of familial IBD was reported, the diagnosis was checked in the hospital records. Two hundred twenty-two controls matched for age and sex (111 from the general population and 111 from orthopedic wards) were also interviewed regarding the possible occurrence of IBD in first-degree relatives. The chi2 test was used to evaluate the difference in proportion of familial occurrence of IBD among individuals with celiac disease and controls. RESULTS: Among 600 first-degree relatives of patients with celiac disease, 10 cases of IBD were identified among first-degree relatives (7 cases of ulcerative colitis and 3 cases of Crohn's disease), whereas only 1 case of IBD was identified among the 1,196 first-degree relatives of control patients (p < 0.01). When ulcerative colitis and Crohn's disease were analyzed separately, only the prevalence of ulcerative colitis was statistically significant (p 相似文献   
26.
27.
European Child & Adolescent Psychiatry - Attention-Deficit/Hyperactivity Disorder (ADHD) comprises disturbances in attention, emotional regulation, and reward-related processes. In spite of the...  相似文献   
28.
Growth factors exert their cellular effects through signal transduction pathways that are initiated by the ligation of growth factors to their cell surface receptors. One of the well-established effectors of growth factor receptors is protein kinase C (PKC), a family of serine-threonine kinases that have been known for years as the main target of the phorbol ester tumor promoters. While there is abundant information regarding downstream PKC effectors and partners, how individual PKC isozymes become activated by growth factors and the regulation of receptor function by PKCs is only partially understood. Moreover, the identification of novel “non-kinase” DAG-binding proteins has added a new level of complexity to the field of DAG signaling.  相似文献   
29.
During the last few years, the number of patients receiving anticoagulant and antiplatelet therapy has increased worldwide. Since this is a chronic treatment, patients receiving it can be expected to need some kind of surgery or intervention during their lifetime that may require treatment discontinuation. The decision to withdraw antithrombotic therapy depends on the patient's thrombotic risk versus hemorrhagic risk. Assessment of both factors will show the precise management of anticoagulant and antiplatelet therapy in these scenarios. The aim of this consensus document, coordinated by the Cardiovascular Thrombosis Working Group of the Spanish Society of Cardiology, and endorsed by most of the Spanish scientific societies of clinical specialities that may play a role in the patient-health care process during the perioperative or periprocedural period, is to recommend some simple and practical guidelines with a view to homogenizing daily clinical practice.Full English text available from: www.revespcardiol.org/en  相似文献   
30.
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