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   3298088篇
  免费   278711篇
  国内免费   13474篇
耳鼻咽喉   44927篇
儿科学   102590篇
妇产科学   84019篇
基础医学   529669篇
口腔科学   89175篇
临床医学   296937篇
内科学   575091篇
皮肤病学   90546篇
神经病学   280874篇
特种医学   131187篇
外国民族医学   225篇
外科学   512877篇
综合类   100219篇
现状与发展   23篇
一般理论   2191篇
预防医学   271084篇
眼科学   75874篇
药学   232665篇
  24篇
中国医学   10014篇
肿瘤学   160062篇
  2021年   55037篇
  2020年   35097篇
  2019年   57975篇
  2018年   70894篇
  2017年   53704篇
  2016年   59442篇
  2015年   73662篇
  2014年   107955篇
  2013年   173093篇
  2012年   88372篇
  2011年   87564篇
  2010年   115691篇
  2009年   120440篇
  2008年   74444篇
  2007年   76903篇
  2006年   88021篇
  2005年   83014篇
  2004年   84837篇
  2003年   75891篇
  2002年   65581篇
  2001年   107149篇
  2000年   99968篇
  1999年   98926篇
  1998年   65014篇
  1997年   62846篇
  1996年   60600篇
  1995年   56166篇
  1994年   50059篇
  1993年   46807篇
  1992年   68048篇
  1991年   64418篇
  1990年   61458篇
  1989年   60549篇
  1988年   55538篇
  1987年   54023篇
  1986年   51225篇
  1985年   50952篇
  1984年   46675篇
  1983年   42697篇
  1982年   40784篇
  1981年   38384篇
  1980年   36322篇
  1979年   37681篇
  1978年   33373篇
  1977年   31346篇
  1976年   28146篇
  1975年   27044篇
  1974年   27217篇
  1973年   26185篇
  1972年   24582篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
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   
82.
83.
Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - Heavy metal concentrations in surface soils of Reserved Forests (RFs) have a significant impact on...  相似文献   
84.
85.
86.
目的了解老年人生命晚期获知疾病相关信息意向及影响因素。方法2016年10月至2017年6月,采用生命晚期疾病信息意向问卷,利用方便抽样法对福州市中心城区7所养老机构及15个社区的414例年龄≥60岁的老年人进行横断面调查,采用单因素分析、多元线性回归与有序多分类logistic回归分析老年人对疾病相关信息的需求水平、获知程度意向及其影响因素。结果414例老年人疾病相关信息需求得分为(17.1±4.9)分;48.8%(202/414)希望详尽知晓,30.7%(127/414)希望选择性了解,20.5%(85/414)不想知道任何信息;多元线性回归分析显示,年龄、文化程度、是否接受/见过其他生命维持治疗(LSTs)是影响老年人疾病相关信息需求水平的主要因素(标准化回归系数分别为-0.141、0.116、0.115,均P<0.05);有序多分类logistic分析显示,年龄(以60~69岁为参照,70~79岁:OR=0.544,95%CI:0.310~0.957;80~89岁:OR=0.526,95%CI:0.289~0.956)、文化程度(以小学及以下为参照,大专及以上:OR=2.166,95%CI:1.093~4.290)、主要生活费来源(以其他补贴为参照,家人支持:OR=7.303,95%CI:1.157~46.108;退休金:OR=9.288,95%CI:1.502~57.415;公积金/储蓄:OR=15.676,95%CI:2.122~115.793)、是否接受/见过其他LSTs(以是为参照,OR=1.985,95%CI:1.150~3.425)是影响老年人疾病相关信息获知程度意向的主要因素。结论老年人生命晚期获知疾病相关信息的意向程度较高,年龄、文化程度、主要生活费来源、是否接受/见过其他生命维持治疗等是其主要影响因素。  相似文献   
87.
88.
Journal of Neuro-Oncology - Adjuvant radiation is often used in patients with low grade gliomas with high-risk characteristics with a recommended dose of 45–54&nbsp;Gy. We used the...  相似文献   
89.
Colorectal cancer (CRC) is the third most diagnosed cancer and the second leading cause of cancer-related mortality in the United States. Across the globe, people in the age group older than 50 are at a higher risk of CRC. Genetic and environmental risk factors play a significant role in the development of CRC. If detected early, CRC is preventable and treatable. Currently, available screening methods and therapies for CRC treatment reduce the incidence rate among the population, but the micrometastasis of cancer may lead to recurrence. Therefore, the challenge is to develop an alternative therapy to overcome this complication. Nanotechnology plays a vital role in cancer treatment and offers targeted chemotherapies directly and selectively to cancer cells, with enhanced therapeutic efficacy. Additionally, nanotechnology elevates the chances of patient survival in comparison to traditional chemotherapies. The potential of nanoparticles includes that they may be used simultaneously for diagnosis and treatment. These exciting properties of nanoparticles have enticed researchers worldwide to unveil their use in early CRC detection and as effective treatment. This review discusses contemporary methods of CRC screening and therapies for CRC treatment, while the primary focus is on the theranostic approach of nanotechnology in CRC treatment and its prospects. In addition, this review aims to provide knowledge on the advancement of nanotechnology in CRC and as a starting point for researchers to think about new therapeutic approaches using nanotechnology.  相似文献   
90.
Maternal and Child Health Journal - Early life exposures can have an impact on a child’s developmental trajectory and children born late preterm (34–36&nbsp;weeks gestational age)...  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