全文获取类型
收费全文 | 21234篇 |
免费 | 1325篇 |
国内免费 | 90篇 |
专业分类
耳鼻咽喉 | 229篇 |
儿科学 | 466篇 |
妇产科学 | 468篇 |
基础医学 | 3321篇 |
口腔科学 | 2354篇 |
临床医学 | 1551篇 |
内科学 | 4266篇 |
皮肤病学 | 582篇 |
神经病学 | 1775篇 |
特种医学 | 443篇 |
外科学 | 2276篇 |
综合类 | 97篇 |
一般理论 | 13篇 |
预防医学 | 2239篇 |
眼科学 | 374篇 |
药学 | 1330篇 |
中国医学 | 178篇 |
肿瘤学 | 687篇 |
出版年
2023年 | 182篇 |
2022年 | 443篇 |
2021年 | 755篇 |
2020年 | 540篇 |
2019年 | 656篇 |
2018年 | 816篇 |
2017年 | 552篇 |
2016年 | 580篇 |
2015年 | 735篇 |
2014年 | 921篇 |
2013年 | 1165篇 |
2012年 | 1676篇 |
2011年 | 1815篇 |
2010年 | 948篇 |
2009年 | 838篇 |
2008年 | 1268篇 |
2007年 | 1270篇 |
2006年 | 1090篇 |
2005年 | 896篇 |
2004年 | 778篇 |
2003年 | 651篇 |
2002年 | 600篇 |
2001年 | 440篇 |
2000年 | 387篇 |
1999年 | 340篇 |
1998年 | 116篇 |
1997年 | 78篇 |
1996年 | 76篇 |
1995年 | 51篇 |
1994年 | 74篇 |
1993年 | 56篇 |
1992年 | 142篇 |
1991年 | 137篇 |
1990年 | 114篇 |
1989年 | 107篇 |
1988年 | 107篇 |
1987年 | 102篇 |
1986年 | 94篇 |
1985年 | 95篇 |
1984年 | 79篇 |
1983年 | 67篇 |
1982年 | 53篇 |
1980年 | 44篇 |
1979年 | 47篇 |
1977年 | 40篇 |
1975年 | 57篇 |
1973年 | 43篇 |
1971年 | 44篇 |
1970年 | 63篇 |
1968年 | 46篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
2.
3.
4.
5.
Caio Henrique de Carvalho Assuno Júlio Csar Trabanco Raquel Fornaziero Gomes Renata Rodrigues Moreira Alessandra Giannella Samelli 《La Medicina del lavoro》2019,110(4):304
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
6.
7.
8.
9.
10.
Joseane Balan Da Silva Gleison Daion Piovezana Bossolani Camila Piva Greicy Brisa Malaquias Dias Jancarlo Gomes Ferreira Diogo Francisco Rossoni 《International journal of environmental health research》2016,26(5-6):578-588
The spatial distribution of enteroparasitosis in an indigenous village from Paraná was evaluated to identify areas of risk for these infections. A cross-sectional study (from November 2010 to June 2011) was performed using Three Faecal Test® and Kato &; Katz method and a questionnaire on housing and hygiene conditions was administered. Local geostatistical analyses were performed to determine the spatial distribution of intestinal parasitic infections. The overall prevalence of enteroparasites was 67.2?% (457/680), and the most prevalent taxa were Ascaris lumbricoides (48.8?%) and Trichuris trichiura (44.7?%). The prevalence of heavy infection by soil-transmitted helminths was 3.6?% and the families lived in houses with an average of 5.1 residents and < 2 bedrooms per household. The average number of species per individual present spatial heterogeneity with the highest values (≥0.8) in areas with high clustering of residences. The visualization of the spatial distribution of intestinal parasites in this indigenous village is an important contribution to determining health risk areas and planning decisions and services. 相似文献