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   3420739篇
  免费   257417篇
  国内免费   10455篇
耳鼻咽喉   46587篇
儿科学   113016篇
妇产科学   95883篇
基础医学   479487篇
口腔科学   94916篇
临床医学   314656篇
内科学   669601篇
皮肤病学   81432篇
神经病学   281053篇
特种医学   131133篇
外国民族医学   1127篇
外科学   512428篇
综合类   77084篇
现状与发展   12篇
一般理论   1338篇
预防医学   266264篇
眼科学   77820篇
药学   249279篇
  12篇
中国医学   7921篇
肿瘤学   187562篇
  2019年   27995篇
  2018年   39063篇
  2017年   30110篇
  2016年   34476篇
  2015年   39041篇
  2014年   54246篇
  2013年   80776篇
  2012年   107907篇
  2011年   114658篇
  2010年   68752篇
  2009年   65430篇
  2008年   106057篇
  2007年   112553篇
  2006年   114376篇
  2005年   110083篇
  2004年   105330篇
  2003年   101417篇
  2002年   97845篇
  2001年   165512篇
  2000年   169378篇
  1999年   141922篇
  1998年   39221篇
  1997年   34595篇
  1996年   34479篇
  1995年   35487篇
  1994年   32404篇
  1993年   30270篇
  1992年   109962篇
  1991年   105656篇
  1990年   102330篇
  1989年   98558篇
  1988年   90387篇
  1987年   88560篇
  1986年   82937篇
  1985年   79359篇
  1984年   59458篇
  1983年   50333篇
  1982年   30058篇
  1981年   26779篇
  1979年   52528篇
  1978年   37150篇
  1977年   31258篇
  1976年   29124篇
  1975年   30747篇
  1974年   36645篇
  1973年   35035篇
  1972年   32955篇
  1971年   30472篇
  1970年   28305篇
  1969年   26952篇
排序方式: 共有10000条查询结果,搜索用时 46 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.
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   
6.
7.
目的 探讨血液肿瘤患者接受化疗后发生肛周感染的危险因素。方法 采用回顾性病例对照研究的方法,对四川省某三级甲等医院血液内科2020年12月—2021年5月收治的进行化疗的348例血液肿瘤住院患者相关资料(人口学特征、疾病特征、医疗及护理病例记录、实验室检查结果)予以回顾性分析,根据出院诊断发生肛周感染的病例作为病例组,其余病例作为对照组,统计血液肿瘤患者接受化疗后肛周感染的发生率,采用单因素分析和二元Logistic回归分析肛周感染的危险因素。结果 348例血液肿瘤化疗患者,发生肛周感染35例,感染率为10.1%;Logistic回归分析显示,年龄<60岁(OR=8.776,P=0.039)、痔疮史(OR=7.733,P<0.001)、肛周感染史(OR=14.981,P<0.001)、腹泻(OR=3.893,P=0.019)及白细胞计数<1×109/L(OR=6.851,P=0.002)是血液肿瘤患者接受化疗后发生肛周感染的独立危险因素。结论 血液肿瘤患者接受化疗后肛周感染的发生率较高,年龄<60岁、痔疮史、肛周感染史、腹泻、白细胞计数<1×109/L导致血液肿瘤化疗患者肛周感染率增加,在护理化疗期的血液肿瘤患者过程中,应该结合肛周感染的危险因素,采取针对性干预措施,降低肛周感染发生率。  相似文献   
8.
9.
10.
In 2019, the scientists who discovered how cells sense and adapt to oxygen availability were awarded the Nobel Prize. This elegant sensing pathway is conserved throughout evolution, and it underpins the physiology and pathology that we, as clinicians in anaesthesia and critical care, encounter on a daily basis. The purpose of this review is to bring hypoxia-inducible factor, and the oxygen-sensing pathway as a whole, to the wider clinical community. We describe how this unifying mechanism was discovered, and how it orchestrates diverse changes such as erythropoiesis, ventilatory acclimatisation, pulmonary vascular remodelling and altered metabolism. We explore the lessons learnt from genetic disorders of oxygen sensing, and the wider implications in evolution of all animal species, including our own. Finally, we explain how this pathway is relevant to our clinical practice, and how it is being manipulated in new treatments for conditions such as cancer, anaemia and pulmonary hypertension.  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