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   4039354篇
  免费   307591篇
  国内免费   10138篇
耳鼻咽喉   57416篇
儿科学   129951篇
妇产科学   111103篇
基础医学   563620篇
口腔科学   116786篇
临床医学   372675篇
内科学   781513篇
皮肤病学   91162篇
神经病学   335423篇
特种医学   158342篇
外国民族医学   1438篇
外科学   608031篇
综合类   90971篇
现状与发展   6篇
一般理论   1721篇
预防医学   322429篇
眼科学   94393篇
药学   300298篇
  11篇
中国医学   7746篇
肿瘤学   212048篇
  2018年   43650篇
  2017年   33581篇
  2016年   38150篇
  2015年   43062篇
  2014年   60631篇
  2013年   92053篇
  2012年   122324篇
  2011年   129808篇
  2010年   77836篇
  2009年   74426篇
  2008年   121826篇
  2007年   129406篇
  2006年   131157篇
  2005年   126802篇
  2004年   122143篇
  2003年   117536篇
  2002年   114365篇
  2001年   186727篇
  2000年   192016篇
  1999年   162163篇
  1998年   45690篇
  1997年   40412篇
  1996年   40033篇
  1995年   41343篇
  1994年   38408篇
  1993年   35936篇
  1992年   129560篇
  1991年   125489篇
  1990年   121265篇
  1989年   117157篇
  1988年   108248篇
  1987年   106665篇
  1986年   100745篇
  1985年   96515篇
  1984年   72525篇
  1983年   61851篇
  1982年   37197篇
  1981年   33449篇
  1979年   66621篇
  1978年   47111篇
  1977年   39857篇
  1976年   37360篇
  1975年   39484篇
  1974年   47906篇
  1973年   45755篇
  1972年   43075篇
  1971年   39899篇
  1970年   37258篇
  1969年   35227篇
  1968年   32421篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
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   
3.
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   
4.
5.
Inflammopharmacology - The inflammatory process is a biological response of the organism to remove injurious stimuli and initiate homeostasis. It has been recognized as a key player in the most...  相似文献   
6.
7.
Neuroscience and Behavioral Physiology - We present here results from analysis of the formation of brain bioelectrical activity in children and adolescents living in the northern region of Russia...  相似文献   
8.
9.
Oral squamous cell carcinomas (OSCCs) develop in genetically altered epithelium in the mucosal lining, also coined as fields, which are mostly not visible but occasionally present as white oral leukoplakia (OL) lesions. We developed a noninvasive genetic assay using next-generation sequencing (NGS) on brushed cells to detect the presence of genetically altered fields, including those that are not macroscopically visible. The assay demonstrated high accuracy in OL patients when brush samples were compared with biopsies as gold standard. In a cohort of Fanconi anemia patients, detection of mutations in prospectively collected oral brushes predicted oral cancer also when visible abnormalities were absent. We further provide insight in the molecular landscape of OL with frequent changes of TP53, FAT1 and NOTCH1. NGS analysis of noninvasively collected samples offers a highly accurate method to detect genetically altered fields in the oral cavity, and predicts development of OSCC in high-risk individuals. Noninvasive genetic screening can be employed to screen high-risk populations for cancer and precancer, map the extension of OL lesions beyond what is visible, map the oral cavity for precancerous changes even when visible abnormalities are absent, test accuracy of promising imaging modalities, monitor interventions and determine genetic progression as well as the natural history of the disease in the human patient.  相似文献   
10.
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