全文获取类型
收费全文 | 19089篇 |
免费 | 1168篇 |
国内免费 | 71篇 |
专业分类
耳鼻咽喉 | 333篇 |
儿科学 | 407篇 |
妇产科学 | 329篇 |
基础医学 | 2565篇 |
口腔科学 | 1859篇 |
临床医学 | 1393篇 |
内科学 | 4224篇 |
皮肤病学 | 454篇 |
神经病学 | 1380篇 |
特种医学 | 423篇 |
外科学 | 2410篇 |
综合类 | 116篇 |
一般理论 | 6篇 |
预防医学 | 1772篇 |
眼科学 | 483篇 |
药学 | 1301篇 |
中国医学 | 140篇 |
肿瘤学 | 733篇 |
出版年
2023年 | 158篇 |
2022年 | 338篇 |
2021年 | 793篇 |
2020年 | 466篇 |
2019年 | 721篇 |
2018年 | 840篇 |
2017年 | 524篇 |
2016年 | 598篇 |
2015年 | 695篇 |
2014年 | 957篇 |
2013年 | 1053篇 |
2012年 | 1739篇 |
2011年 | 1750篇 |
2010年 | 894篇 |
2009年 | 741篇 |
2008年 | 1136篇 |
2007年 | 1159篇 |
2006年 | 956篇 |
2005年 | 847篇 |
2004年 | 807篇 |
2003年 | 593篇 |
2002年 | 525篇 |
2001年 | 278篇 |
2000年 | 239篇 |
1999年 | 233篇 |
1998年 | 104篇 |
1997年 | 69篇 |
1996年 | 44篇 |
1995年 | 45篇 |
1994年 | 32篇 |
1993年 | 36篇 |
1992年 | 86篇 |
1991年 | 89篇 |
1990年 | 86篇 |
1989年 | 75篇 |
1988年 | 72篇 |
1987年 | 70篇 |
1986年 | 59篇 |
1985年 | 55篇 |
1984年 | 25篇 |
1983年 | 35篇 |
1982年 | 17篇 |
1979年 | 18篇 |
1978年 | 20篇 |
1976年 | 18篇 |
1975年 | 22篇 |
1974年 | 23篇 |
1973年 | 25篇 |
1969年 | 22篇 |
1967年 | 17篇 |
排序方式: 共有10000条查询结果,搜索用时 15 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.
Phenotypic and genetic features of enteropathogenic Escherichia coli isolates from diarrheal children in the Ribeirão Preto metropolitan area,São Paulo State,Brazil
下载免费PDF全文
![点击此处可从《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》网站下载免费的PDF全文](/ch/ext_images/free.gif)
André Pitondo‐Silva Gerson Nakazato Juliana P. Falcão Kinue Irino Roberto Martinez Ana Lúcia C. Darini Rodrigo Tavanelli Hernandes 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2015,123(2):128-135
This study was designed to characterize a collection of 60 enteropathogenic Escherichia coli (EPEC) isolates from diarrheic feces of patients in the Ribeirão Preto metropolitan area regarding different phenotypic and molecular features. We examined antibiotic resistance profiles, occurrence of virulence factors‐encoding genes, intimin subtypes and the correlation of serotypes among typical (tEPEC) and atypical (aEPEC) EPEC isolates. The results demonstrated that atypical EPEC was more heterogeneous than typical EPEC concerning the characteristics investigated and 45.2% do not belong to classical EPEC serogroups. Intimin subtype β was the most frequent among the EPEC isolates (46.7%), being detected in both tEPEC and aEPEC. The majority of aEPEC isolates presented localized adherence‐like (LAL) pattern to HEp‐2 cells, although aEPEC isolates displaying diffuse adherence (DA) or non‐adherent were also detected. High prevalence of antimicrobial resistance was found for ampicillin, cephalothin, sulfonamide and tetracycline. In general, tEPEC isolates were more resistant to the antimicrobials tested than aEPEC isolates. 相似文献
8.
9.
10.
Spread of an Enterococcus faecalis sequence type 6 (CC2) clone in patients undergoing selective decontamination of the digestive tract
下载免费PDF全文
![点击此处可从《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Izaskun Muruzábal‐Lecumberri Cecilia Girbau Andrés Canut Rodrigo Alonso Aurora Fernández‐Astorga 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2015,123(3):245-251
Enterococcus faecalis (E. faecalis) is a common cause of nosocomial infection in immunocompromised patients. The presence and dissemination of high‐risk clonal complexes, such as CC2, is an ongoing problem in hospitals. The aim of this work was to characterize 24 E. faecalis isolates from ICU patients undergoing selective decontamination of the digestive tract (SDD) by phenotypical (antimicrobial susceptibility) and genotypical (presence of virulence genes, RAPD‐PCR and MLST) methods. Our results showed high prevalence of the ST6 E. faecalis clone (91.6%), especially adapted to the hospital environment, with a multidrug resistance pattern and a multitude of putative virulence genes. In addition, ST179 (4.2%) and ST191 (4.2%) were detected. By RAPD–PCR analysis, the 22 isolates identified as ST6 showed six different DNA patterns, while the two remaining isolates, ST179 and ST191, showed two additional profiles. CC2 is a known clonal complex with high adaptability to hospital environment and worldwide distribution. The high prevalence of the ST6 clone in the studied population could be related to the presence of gentamicin in the SDD mixture since most strains were gentamicin resistant. Consequently, strict surveillance should be applied for rapid detection and control of this clone to prevent future spread outside the ICU. 相似文献