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   1602956篇
  免费   131295篇
  国内免费   2578篇
耳鼻咽喉   21655篇
儿科学   52953篇
妇产科学   46245篇
基础医学   227877篇
口腔科学   47198篇
临床医学   140963篇
内科学   314974篇
皮肤病学   34098篇
神经病学   130242篇
特种医学   64746篇
外国民族医学   474篇
外科学   243895篇
综合类   39714篇
现状与发展   3篇
一般理论   544篇
预防医学   122898篇
眼科学   36699篇
药学   121337篇
  3篇
中国医学   2974篇
肿瘤学   87337篇
  2018年   14777篇
  2016年   12912篇
  2015年   15040篇
  2014年   20664篇
  2013年   31385篇
  2012年   42603篇
  2011年   44813篇
  2010年   26374篇
  2009年   25334篇
  2008年   43039篇
  2007年   45282篇
  2006年   46097篇
  2005年   44723篇
  2004年   44138篇
  2003年   42226篇
  2002年   41348篇
  2001年   75743篇
  2000年   78370篇
  1999年   66430篇
  1998年   17742篇
  1997年   16342篇
  1996年   16322篇
  1995年   16027篇
  1994年   15077篇
  1993年   14222篇
  1992年   55448篇
  1991年   53789篇
  1990年   52577篇
  1989年   50843篇
  1988年   47236篇
  1987年   46570篇
  1986年   44296篇
  1985年   42857篇
  1984年   32040篇
  1983年   27574篇
  1982年   16147篇
  1981年   14439篇
  1980年   13567篇
  1979年   30469篇
  1978年   21075篇
  1977年   17769篇
  1976年   16706篇
  1975年   17580篇
  1974年   21495篇
  1973年   20678篇
  1972年   18854篇
  1971年   17771篇
  1970年   16291篇
  1969年   15270篇
  1968年   13951篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
72.
The first COVID-19 vaccination was given in December 2020 and there is an effort to vaccinate the international population on a massive scale. Common side effects from the vaccine include headache and tiredness. Regional lymphadenopathy has been described in relation to other vaccines. We describe two cases of supraclavicular reactive lymphadenopathy presenting in patients who had the COVID vaccination in the ipsilateral arm. Awareness of this diagnosis is important for patients presenting to the neck lump clinic.  相似文献   
73.
74.
Journal of Behavioral Medicine - Understanding associations between mothers’ and children’s physical activity and sedentary behavior on more fine-grained timescales can provide insights...  相似文献   
75.
76.
The aim of this study was to analyse the effect of body mass index (BMI), both low and high values, on the perioperative complication rate in patients with oral squamous cell carcinoma (OSCC). The medical records of 259 patients operated between 2014 and 2017 for OSCC were reviewed. Univariate and multivariate analyses were performed. Sixty of the 259 patients developed 87 complications. Low or high BMI was not associated with the perioperative complication rate. A longer operating time and increased blood loss were associated with a higher perioperative complication rate and higher Clavien–Dindo grade. Low BMI, American Society of Anesthesiologists score 2 and 3, a longer operating time, and increased blood loss were associated with a longer hospital stay. Low BMI was associated with a longer hospital stay. Neither low nor high BMI was associated with the perioperative complication rate. A longer operating time and increased blood loss were associated with a higher perioperative complication rate and higher Clavien–Dindo grade.  相似文献   
77.
78.
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Gefahrstoffe sind in der Arbeitswelt allgegenwärtig. Beschäftigte aus allen Branchen sind bei ihrer Arbeit mit...  相似文献   
79.
80.

Objectives

To investigate whether functional overreaching affects locomotor system behaviour when running at fixed relative intensities and if any effects were associated with changes in running performance.

Design

Prospective intervention study.

Methods

Ten trained male runners completed three training blocks in a fixed order. Training consisted of one week of light training (baseline), two weeks of heavy training designed to induce functional overreaching, and ten days of light taper training designed to allow athletes to recover from, and adapt to, the heavy training. Locomotor behaviour, 5-km time trial performance, and subjective reports of training status (Daily Analysis of Life Demands for Athletes (DALDA) questionnaire) were assessed at the completion of each training block. Locomotor behaviour was assessed using detrended fluctuation analysis of stride intervals during running at speeds corresponding to 65% and 85% of maximum heart rate (HRmax) at baseline.

Results

Time trial performance (effect size ±95% confidence interval (ES): 0.16 ± 0.06; p < 0.001), locomotor behaviour at 65% HRmax (ES: ?1.12 ± 0.95; p = 0.026), and DALDA (ES: 2.55 ± 0.80; p < 0.001) were all detrimentally affected by the heavy training. Time trial performance improved relative to baseline after the taper (ES: ?0.16 ± 0.10; p = 0.003) but locomotor behaviour at 65% HRmax (ES: ?1.18 ± 1.17; p = 0.048) and DALDA (ES: 0.92 ± 0.90; p = 0.045) remained impaired.

Conclusions

Locomotor behaviour during running at 65% HRmax was impaired by functional overreaching and remained impaired after a 10-day taper, despite improved running performance. Locomotor changes may increase injury risk and should be considered within athlete monitoring programs independently of performance changes.  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