全文获取类型
收费全文 | 17376篇 |
免费 | 1326篇 |
国内免费 | 74篇 |
专业分类
耳鼻咽喉 | 363篇 |
儿科学 | 603篇 |
妇产科学 | 404篇 |
基础医学 | 2528篇 |
口腔科学 | 559篇 |
临床医学 | 1584篇 |
内科学 | 3620篇 |
皮肤病学 | 254篇 |
神经病学 | 1797篇 |
特种医学 | 454篇 |
外科学 | 2082篇 |
综合类 | 144篇 |
一般理论 | 9篇 |
预防医学 | 1344篇 |
眼科学 | 225篇 |
药学 | 1076篇 |
中国医学 | 44篇 |
肿瘤学 | 1686篇 |
出版年
2023年 | 141篇 |
2022年 | 235篇 |
2021年 | 518篇 |
2020年 | 326篇 |
2019年 | 429篇 |
2018年 | 459篇 |
2017年 | 384篇 |
2016年 | 422篇 |
2015年 | 467篇 |
2014年 | 632篇 |
2013年 | 810篇 |
2012年 | 1207篇 |
2011年 | 1344篇 |
2010年 | 668篇 |
2009年 | 592篇 |
2008年 | 1040篇 |
2007年 | 965篇 |
2006年 | 913篇 |
2005年 | 919篇 |
2004年 | 892篇 |
2003年 | 799篇 |
2002年 | 733篇 |
2001年 | 258篇 |
2000年 | 253篇 |
1999年 | 239篇 |
1998年 | 166篇 |
1997年 | 129篇 |
1996年 | 98篇 |
1995年 | 115篇 |
1994年 | 97篇 |
1993年 | 89篇 |
1992年 | 184篇 |
1991年 | 165篇 |
1990年 | 126篇 |
1989年 | 138篇 |
1988年 | 159篇 |
1987年 | 135篇 |
1986年 | 157篇 |
1985年 | 124篇 |
1984年 | 77篇 |
1983年 | 96篇 |
1982年 | 67篇 |
1980年 | 63篇 |
1979年 | 71篇 |
1978年 | 66篇 |
1976年 | 52篇 |
1974年 | 61篇 |
1973年 | 69篇 |
1972年 | 62篇 |
1971年 | 60篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
Alessia Scarselli Silvia Di Cesare Claudia Capponi Simona Cascioli Maria L. Romiti Gigliola Di Matteo Alessandra Simonetti Paolo Palma Andrea Finocchi Barbarella Lucarelli Rita M. Pinto Ippolita Rana Giuseppe Palumbo Maurizio Caniglia Paolo Rossi Rita Carsetti Caterina Cancrini Alessandro Aiuti 《Journal of clinical immunology》2015,35(4):373-383
2.
3.
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
4.
5.
Katherine M. Duszynski Nicole L. Pratt John W. Lynch Jesia G. Berry Michael S. Gold 《Vaccine》2019,37(2):280-288
Objective
To determine whether differences in combination DTaP vaccine types at 2, 4 and 6?months of age were associated with mortality (all-cause or non-specific), within 30?days of vaccination.Design
Observational nationwide cohort study.Setting
Linked population data from the Australian Childhood Immunisation Register and National Death Index.Participants
Australian infants administered a combination trivalent, quadrivalent or hexavalent DTaP vaccine (DTaP types) between January 1999 and December 2010 at 2, 4 and 6?months as part of the primary vaccination series. The study population included 2.9, 2.6, & 2.3?million children in the 2, 4 and 6?month vaccine cohorts, respectively.Main outcome measures
Infants were evaluated for the primary outcome of all-cause mortality within 30?days. A secondary outcome was non-specific mortality (unknown cause of death) within 30?days of vaccination. Non-specific mortality was defined as underlying or other cause of death codes, R95 ‘Sudden infant death syndrome’, R96 ‘Other sudden death, cause unknown’, R98 ‘Unattended death’, R99 ‘Other ill-defined and unspecified cause of mortality’ or where no cause of death was recorded.Results
The rate of 30?day all-cause mortality was low and declined from 127.4 to 59.3 deaths per 100,000 person-years between 2 and 6?month cohorts. When compared with trivalent DTaP vaccines, no elevated risk in all-cause or non-specific mortality was seen with any quadrivalent or hexavalent DTaP vaccines, for any cohort.Conclusion
Use of routine DTaP combination vaccines with differing disease antigens administered during the first six months of life is not associated with infant mortality. 相似文献6.
Flavia Temperilli Aldona Rina Isabella Massimi Anna Lisa Montemari Maria Luisa Guarino Alessandra Zicari 《Platelets》2015,26(8):783-787
Serum thromboxane-B2 (TxB2), together with arachidonic acid (AA)-induced platelet aggregation, are, at the moment, the most used tests to identify patients displaying high on-aspirin treatment platelet reactivity (HAPR). Both tests are specific for aspirin action on cyclooxygenase-1. While the correlation between serum TxB2 assay and clinical outcome is established, data are conflicting with regard to aspirin treatment and a possible association with AA-stimulated platelet markers and clinical outcome. To understand such discrepancy, we performed a retrospective study to compare both assays. We collected data from 132 patients receiving a daily dose of aspirin (100?mg/day) and data from 48 patients receiving aspirin on alternate days. All Patients who received a daily dose of aspirin were studied for AA-induced platelet aggregation together with serum TxB2 levels and AA-induced TxB2 formation was also studied in 71 patients out of entire population. Consistent with recommendations in the literature, we defined HAPR by setting a cut-off point at 3.1?ng/ml for serum levels of thromboxane B2 and 20% for AA-induced platelet aggregation. According to this cut-off point, we divided our overall population into two groups: (1) TxB2?<?3.1?ng/ml and (2) TxB2?>?3.1?ng/ml. We found low agreement between such tests to identify patients displaying HAPR. Our results show that AA-induced platelet aggregation >20% identify a smaller number of HAPR patients in comparison with TxB2. A good correlation between serum TxB2 and arachidonic acid-induced TxB2 production was found (r?=?0.76619). 相似文献
7.
Amanda Leal Rocha Alessandra Figueiredo De Souza Laiz Fernandes Mendes Nunes Nayara Dias de Souza Cunha Clia Regina Moreira Lanza Denise Vieira Travassos Tarcília Aparecida da Silva 《Pediatric dermatology》2019,36(1):e27-e30
Drug‐induced reactions are complications associated with high mortality and significant morbidity. Stevens–Johnson Syndrome (SJS) and toxic epidermal necrolysis (TEN) are examples of these conditions, which are characterized by skin and mucous lesions. Here, we report a case of a 9‐year‐old girl who presented with blisters associated with an extensive vesicular rash and multiple ulcerations on the lips and oral cavity. A drug‐induced hypersensitivity reaction to antibiotics was suspected, and a diagnosis of TEN was made. The patient was managed with withdrawal of the suspected causative agent, and the oral lesions were treated with low‐level laser therapy (LLLT) and oral hygiene. This case highlights that TEN requires interdisciplinary intervention with dental assistance and follow‐up to improve symptoms, nutrition, systemic condition, and quality of life. 相似文献
8.
9.
10.
Enantiomeric interaction of flurbiprofen in the rat 总被引:2,自引:0,他引:2
Flurbiprofen [FL, (+/-)-2-(2-fluoro-4-biphenylyl)propionic acid] is a 2-arylpropionic acid nonsteroidal anti-inflammatory drug which is commercially available as a racemate. The anti-inflammatory activity of FL, however, appears to be mainly due to the S enantiomer. Recently, it has been postulated that, in both humans and rats, the two enantiomers of FL may interact when racemic doses are given. This study examines the above postulate in the rat by administration of single iv doses of racemic FL (10 mg/kg), and R- and S-FL (5 mg/kg of each). Plasma concentrations (0-12 h) of the enantiomers were measured using a stereospecific HPLC assay. A significant interaction was noticed between the enantiomers: mean AUC +/- SD of R-FL was reduced from 115.3 +/- 21.3 to 49.0 +/- 10.4 mg/L.h as a result of S-FL coadministration. A trend towards reduced S-FL plasma concentration was also evident when the enantiomer was given as the racemate [mean AUC +/- SD; 176.8 +/- 37.7 racemate versus 241.4 +/- 86.2 mg/L.h alone]. The reduction in S-FL, however, was not significant due perhaps to the observed interanimal variation. While the enantiomeric interaction caused a significant enlargement of the volume of distribution of R-FL, it failed to alter the terminal half-life of the enantiomer. It is suggested that the interaction is a result of displacement from plasma protein binding sites of one enantiomer by the other. 相似文献