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   5637篇
  免费   337篇
  国内免费   34篇
耳鼻咽喉   84篇
儿科学   141篇
妇产科学   127篇
基础医学   812篇
口腔科学   367篇
临床医学   498篇
内科学   1312篇
皮肤病学   129篇
神经病学   573篇
特种医学   72篇
外科学   544篇
综合类   21篇
一般理论   2篇
预防医学   503篇
眼科学   71篇
药学   385篇
中国医学   38篇
肿瘤学   329篇
  2023年   60篇
  2022年   67篇
  2021年   261篇
  2020年   155篇
  2019年   258篇
  2018年   297篇
  2017年   150篇
  2016年   167篇
  2015年   213篇
  2014年   291篇
  2013年   319篇
  2012年   549篇
  2011年   596篇
  2010年   291篇
  2009年   266篇
  2008年   390篇
  2007年   344篇
  2006年   326篇
  2005年   247篇
  2004年   224篇
  2003年   205篇
  2002年   179篇
  2001年   21篇
  2000年   12篇
  1999年   21篇
  1998年   13篇
  1997年   9篇
  1996年   8篇
  1995年   14篇
  1994年   5篇
  1993年   6篇
  1992年   8篇
  1991年   5篇
  1990年   4篇
  1989年   1篇
  1988年   3篇
  1987年   4篇
  1985年   2篇
  1983年   2篇
  1982年   2篇
  1979年   1篇
  1978年   1篇
  1977年   1篇
  1975年   1篇
  1974年   1篇
  1973年   1篇
  1972年   2篇
  1971年   2篇
  1970年   1篇
  1966年   1篇
排序方式: 共有6008条查询结果,搜索用时 22 毫秒
1.
Journal of Digital Imaging - Vertebral Compression Fracture (VCF) occurs when the vertebral body partially collapses under the action of compressive forces. Non-traumatic VCFs can be secondary to...  相似文献   
2.
Objective:The present study evaluates a training program for fitting different hearing protection devices (HPDs) based on personal attenuation rating (PAR) before, immediately after, and six months after training.Methods:A total of 67 workers from a public university in the city of São Paulo, Brazil, were invited to participate in the measurement of PARs for foam and silicone protectors through the 3M™ E-A-Rfit Validation System. Two evaluations were performed for each protector at each sampling date: one after reading printed material (the package instructions) and another after being trained by an audiologist. The same procedures were repeated after six months. The final sample consisted of 30 individuals. ANOVA was used for statistical analysis.Results:Larger PAR values were observed after training by the audiologist, and smaller values were observed after six months. Then, after re-training, the values increased again. There were no statistically significant differences in PAR among the HPDs tested. Even after the two training sessions, 23 to 27% of the subjects did not obtain adequate PAR values.Conclusion:These findings emphasize the need for continual worker training in the correct fit of earplug HPDs and the importance of longitudinal PAR monitoring. In addition, some workers, despite the training provided, did not adapt to the HPDs used. Therefore, it is essential that other protection methods and/or other HPD types are made available to these individuals.Key words: Hearing, noise-induced hearing loss, occupational health, personal protective equipment, hearing protection devices  相似文献   
3.
4.
5.
ABSTRACT

Prior studies on substance use in Brazil have not focused on opioid misuse, previously thought to be nearly non-existent. This paper presents new findings on heroin and non-medical use of opioid analgesics. Data come from the 2015 Brazilian Household Survey on Substance Use (BHSU-3), a nationally representative survey estimating epidemiological parameters related to substance use by residents across Brazil. BHSU-3 used stratified multi-stage probability sampling across multiple geographic domains of interest, resulting in 16,273 interviews with household residents. Lifetime heroin use among Brazilians was 0.3 (95% C.I:0.2–0.4). Lifetime, past-year, and past-month non-medical use of opioid analgesics were respectively 2.9 (95%C.I.:2.3–3.4), 1.4 (95%C.I.:1.1–1.7) and 0.6 (95%C.I.:0.4–0.8). Past-year prevalence of non-medical opioid analgesics use was lower among males [Prevalence Ratio (PR): 0.54 (95% C.I.:0.36–0.78)], those aged 12–24 [0.56 (95% C.I.:0.34–0.92)], persons with monthly family incomes between R$1,501–3,000 [0.59 (95% C.I.:0.38–0.92)] or greater than R$3,000 [0.64 (95% C.I.:0.42–0.98)], and persons who were unemployed [0.65 (95% C.I.:0.46–0.92)]. Non-medical use of opioids in Brazil may be more prevalent than previously recognised. Proper measurement and evaluation of opioid misuse across Brazil and other Latin American countries is critical to understand and prevent opioid-related harms.  相似文献   
6.
7.
8.
9.
Lasers in Medical Science - Using light sources in phototherapy has presented promising results regarding several types of facial and body skin affections for centuries. The neodymium-doped yttrium...  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