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   695674篇
  免费   64231篇
  国内免费   23146篇
耳鼻咽喉   5638篇
儿科学   10445篇
妇产科学   13392篇
基础医学   84448篇
口腔科学   11468篇
临床医学   57377篇
内科学   91880篇
皮肤病学   8682篇
神经病学   33756篇
特种医学   16466篇
外国民族医学   462篇
外科学   65712篇
综合类   99331篇
现状与发展   71篇
一般理论   34篇
预防医学   44343篇
眼科学   7543篇
药学   84052篇
  218篇
中国医学   30721篇
肿瘤学   117012篇
  2024年   1354篇
  2023年   10411篇
  2022年   20405篇
  2021年   29373篇
  2020年   25347篇
  2019年   25022篇
  2018年   24320篇
  2017年   24086篇
  2016年   24880篇
  2015年   27500篇
  2014年   46451篇
  2013年   48628篇
  2012年   40504篇
  2011年   44305篇
  2010年   37033篇
  2009年   37372篇
  2008年   35632篇
  2007年   35264篇
  2006年   31707篇
  2005年   27777篇
  2004年   22994篇
  2003年   20395篇
  2002年   16159篇
  2001年   14804篇
  2000年   12542篇
  1999年   11070篇
  1998年   9333篇
  1997年   8411篇
  1996年   7705篇
  1995年   7187篇
  1994年   6346篇
  1993年   5379篇
  1992年   4728篇
  1991年   4271篇
  1990年   3618篇
  1989年   3261篇
  1988年   3038篇
  1987年   2543篇
  1986年   2195篇
  1985年   3205篇
  1984年   3069篇
  1983年   2052篇
  1982年   2178篇
  1981年   1872篇
  1980年   1672篇
  1979年   1277篇
  1978年   944篇
  1977年   750篇
  1976年   747篇
  1975年   498篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
41.
42.
43.
Acute Coma     
《Neurologic Clinics》2021,39(2):257-272
  相似文献   
44.
《Cancer cell》2021,39(9):1214-1226.e10
  1. Download : Download high-res image (204KB)
  2. Download : Download full-size image
  相似文献   
45.
46.
Abstract

Purpose

Financial hardship can be a major cause of distress among persons with cancer, resulting in chronic stress and impacting physical and emotional health. This paper provides an analysis of the lived experience of cancer patients’ financial hardship from diagnosis to post-treatment.  相似文献   
47.
48.
ObjectivesMap regional lymph node metastases for lateralized oral cavity squamous cell carcinoma (OCSCC) and evaluate factors associated with regional metastases and recurrence.Materials and methodsRetrospective cohort study of 715 patients with lateralized OCSCC surgically treated in 1997–2011. Analysis was performed using log-rank, Kaplan-Meier, and multivariable logistic and Cox regression.ResultsRegional metastases were identified in ipsilateral levels IIA (24%), IB (18%), III (13%), V (9%), IV (7%), IA (2%) and IIB (1%) and the contralateral neck (3%). Lymphovascular invasion (LVI) (Hazard Ratio [HR] 2.2, 95% Confidence Interval [CI] 1.2–3.9) and T category (T3 vs. T1: HR 4.1, 95% CI 1.9–9.3; T4 vs. T1: HR 2.3, 95% CI 1.2–4.3) were associated with regional metastases. Most (71%) isolated regional metastatic recurrences were in undissected levels of the neck, including 58% in levels IV and V. Tumors of the hard palate (HR 4.3, 95% CI 1.2–16.1), upper alveolus (HR 3.2, 95% CI 1.0–4.7) or with LVI (HR 2.0, 95% CI 1.0–3.9) were associated with isolated regional recurrence. For upper alveolar/hard palate tumors, depth of invasion (DOI) ≥4 mm (P = .003) and LVI (P = .04) were associated with regional metastases.ConclusionsFor lateralized OCSCC, elective neck dissection of level IIB or the contralateral neck may rarely be needed, but additional surgical or radiation treatment of levels IV and V may be considered based on patient risk factors, including T category 3–4 or LVI. For upper alveolar/hard palate tumors, DOI ≥4 mm is an appropriate threshold for elective neck dissection.  相似文献   
49.
《Immunity》2022,55(9):1725-1731.e4
  1. Download : Download high-res image (182KB)
  2. Download : Download full-size image
  相似文献   
50.
《Digestive and liver disease》2022,54(11):1486-1493
BackgroundCold snare polypectomy (CSP) is a promising technique for the removal of sessile serrated polyps (SSPs) ≥ 10 mm. However, the efficacy and safety of this technique remain undetermined.AimsWe aimed to comprehensively evaluate the efficacy and safety of CSP for SSPs ≥ 10 mm.MethodsPubMed, EMBASE, Web of Science and Cochrane Library were searched up to January 2021.ResultsA total of 10 studies consisting of 1727 SSPs (range, 10–40 mm) from 1021 patients were included. The overall rates of technical success, adverse events (AEs) and residual SSPs were 100%, 0.7% and 2.9%, respectively. Subgroup analysis showed that the rates of technical success and AEs were comparable between CSP and cold endoscopic mucosal resection (EMR) (99.9% vs. 100% and 1.3% vs. 0.5%, respectively), between the proximal and distal colon (100% vs. 99.9% and 0.3% vs. 0, respectively), and between polyps of 10–19 mm and ≥20 mm (99.8% vs. 100% and 0.9% vs. 0, respectively). However, subgroup analysis showed that the rate of residual SSPs was slightly lower in CSP compared with cold EMR (1.3% vs. 3.9%), as well as in polyps of 10–19 mm compared with those ≥20 mm (3.1% vs. 4.7%).ConclusionCSP was an effective and safe technique for removing SSPs ≥ 10 mm.  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