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   1418341篇
  免费   116872篇
  国内免费   3345篇
耳鼻咽喉   18568篇
儿科学   47085篇
妇产科学   41474篇
基础医学   201392篇
口腔科学   38204篇
临床医学   127572篇
内科学   284746篇
皮肤病学   33603篇
神经病学   117730篇
特种医学   54359篇
外国民族医学   465篇
外科学   213014篇
综合类   33055篇
现状与发展   3篇
一般理论   500篇
预防医学   111085篇
眼科学   31803篇
药学   99162篇
  1篇
中国医学   3269篇
肿瘤学   81468篇
  2021年   10194篇
  2019年   11954篇
  2018年   16946篇
  2017年   12925篇
  2016年   14500篇
  2015年   16305篇
  2014年   23074篇
  2013年   34118篇
  2012年   46359篇
  2011年   48972篇
  2010年   28777篇
  2009年   27594篇
  2008年   45205篇
  2007年   47842篇
  2006年   48355篇
  2005年   46831篇
  2004年   44666篇
  2003年   42436篇
  2002年   40899篇
  2001年   73240篇
  2000年   74724篇
  1999年   61503篇
  1998年   16228篇
  1997年   14516篇
  1996年   14685篇
  1995年   14838篇
  1994年   13486篇
  1993年   12651篇
  1992年   46103篇
  1991年   43737篇
  1990年   41714篇
  1989年   39774篇
  1988年   36369篇
  1987年   35544篇
  1986年   33060篇
  1985年   31483篇
  1984年   23953篇
  1983年   20151篇
  1982年   12322篇
  1981年   10882篇
  1979年   20875篇
  1978年   14707篇
  1977年   12172篇
  1976年   11438篇
  1975年   11712篇
  1974年   14113篇
  1973年   13680篇
  1972年   12741篇
  1971年   11577篇
  1970年   11000篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
Modified-release opioids are often prescribed for the management of moderate to severe acute pain following total hip and knee arthroplasty, despite recommendations against their use due to increasing concerns regarding harm. The primary objective of this multicentre study was to examine the impact of modified-release opioid use on the incidence of opioid-related adverse events compared with immediate-release opioid use, among adult inpatients following total hip or knee arthroplasty. Data for total hip and knee arthroplasty inpatients receiving an opioid analgesic for postoperative analgesia during hospitalisation were collected from electronic medical records of three tertiary metropolitan hospitals in Australia. The primary outcome was the incidence of opioid-related adverse events during hospital admission. Patients who received modified with or without immediate-release opioids were matched to those receiving immediate-release opioids only (1:1) using nearest neighbour propensity score matching with patient and clinical characteristics as covariates. This included total opioid dose received. In the matched cohorts, patients given modified-release opioids (n = 347) experienced a higher incidence of opioid-related adverse events overall, compared with those given immediate-release opioids only (20.5%, 71/347 vs. 12.7%, 44/347; difference in proportions 7.8% [95%CI 2.3–13.3%]). Modified-release opioid use was associated with an increased risk of harm when used for acute pain during hospitalisation after total hip or knee arthroplasty.  相似文献   
2.
Post-induction hypotension is common and associated with postoperative complications. We hypothesised that pneumatic leg compression reduces post-induction hypotension in elderly patients undergoing robot-assisted laparoscopic prostatectomy. In this double-blind randomised study, patients were allocated randomly to the pneumatic leg compression group (n = 50) or control (n = 50). In the intervention group, pneumatic leg compression was initiated before induction of anaesthesia. In the control group, pneumatic leg compression was initiated 20 min after anaesthesia induction. The primary outcome was the incidence of post-induction hypotension in these groups. Post-induction hypotension was defined as systolic blood pressure < 90 mmHg during the first 20 min after induction. Haemodynamic variables and area under the curve of post-induction systolic blood pressure over time were assessed. Complications associated with pneumatic leg compression were recorded, including: peripheral neuropathy; compartment syndrome; extensive bullae beneath the leg sleeves; and pulmonary thromboembolism. The incidence of post-induction hypotension decreased in the pneumatic leg compression group compared with that in the control group; 5 (10%) vs. 29 (58%), respectively, p < 0.001. In the pneumatic leg compression group, the lowest systolic, diastolic and mean blood pressures 20 min after induction of anaesthesia were significantly greater than the control group. Pneumatic leg compression resulted in an increased area under the curve of systolic blood pressure in the first 20 min after induction, p = 0.001. There were no pneumatic leg compression-related complications. Pneumatic leg compression reduced post-induction hypotension in elderly patients undergoing robot-assisted laparoscopic prostatectomy, suggesting that it is an effective and safe intervention to prevent post-induction hypotension among elderly patients undergoing general anaesthesia.  相似文献   
3.
4.
5.
6.
7.
Journal of Molecular Medicine - Chronic exposure to high levels of particulate matter (PM) is correlated to a higher prevalence of cardio-metabolic disturbances. Adipose tissue represents a pivotal...  相似文献   
8.
9.
10.
Postbariatric loss of muscle tissue could negatively affect long-term health due to its role in various bodily processes, such as metabolism and functional capacity. This meta-analysis aimed to unravel time-dependent changes in the magnitude and progress of lean body mass (LBM), fat-free mass (FFM), and skeletal muscle mass (SMM) loss following bariatric surgery. A systematic literature search was conducted in Pubmed, Embase, and Web of Science. Fifty-nine studies assessed LBM (n = 37), FFM (n = 20), or SMM (n = 3) preoperatively and ≥1 time points postsurgery. Random-effects meta-analyses were performed to determine pooled loss per outcome parameter and follow-up time point. At 12-month postsurgery, pooled LBM loss was ?8.13 kg [95%CI ?9.01; ?7.26]. FFM loss and SMM loss were ?8.23 kg [95%CI ?10.74; ?5.73] and ?3.18 kg [95%CI ?5.64; ?0.71], respectively. About 55% of 12-month LBM loss occurred within 3-month postsurgery, followed by a more gradual decrease up to 12 months. Similar patterns were seen for FFM and SMM. In conclusion, >8 kg of LBM and FFM loss was observed within 1-year postsurgery. LBM, FFM, and SMM were predominantly lost within 3-month postsurgery, highlighting that interventions to mitigate such losses should be implemented perioperatively.  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