全文获取类型
收费全文 | 2386536篇 |
免费 | 167824篇 |
国内免费 | 4468篇 |
专业分类
耳鼻咽喉 | 35194篇 |
儿科学 | 75476篇 |
妇产科学 | 69705篇 |
基础医学 | 340628篇 |
口腔科学 | 69883篇 |
临床医学 | 202598篇 |
内科学 | 464628篇 |
皮肤病学 | 52069篇 |
神经病学 | 187818篇 |
特种医学 | 93768篇 |
外国民族医学 | 778篇 |
外科学 | 369809篇 |
综合类 | 53048篇 |
现状与发展 | 7篇 |
一般理论 | 711篇 |
预防医学 | 170891篇 |
眼科学 | 56286篇 |
药学 | 181166篇 |
5篇 | |
中国医学 | 4988篇 |
肿瘤学 | 129372篇 |
出版年
2018年 | 21627篇 |
2015年 | 21449篇 |
2014年 | 29838篇 |
2013年 | 45700篇 |
2012年 | 60929篇 |
2011年 | 65047篇 |
2010年 | 38643篇 |
2009年 | 36830篇 |
2008年 | 62870篇 |
2007年 | 68398篇 |
2006年 | 69375篇 |
2005年 | 67742篇 |
2004年 | 65487篇 |
2003年 | 63578篇 |
2002年 | 62720篇 |
2001年 | 109034篇 |
2000年 | 112204篇 |
1999年 | 95297篇 |
1998年 | 26300篇 |
1997年 | 23796篇 |
1996年 | 23459篇 |
1995年 | 22161篇 |
1994年 | 20985篇 |
1993年 | 19310篇 |
1992年 | 75675篇 |
1991年 | 73974篇 |
1990年 | 72862篇 |
1989年 | 71105篇 |
1988年 | 66260篇 |
1987年 | 65108篇 |
1986年 | 62210篇 |
1985年 | 59248篇 |
1984年 | 44374篇 |
1983年 | 38103篇 |
1982年 | 22755篇 |
1981年 | 20434篇 |
1979年 | 42372篇 |
1978年 | 30087篇 |
1977年 | 26040篇 |
1976年 | 24083篇 |
1975年 | 26946篇 |
1974年 | 31897篇 |
1973年 | 30879篇 |
1972年 | 29563篇 |
1971年 | 27544篇 |
1970年 | 25859篇 |
1969年 | 24979篇 |
1968年 | 23483篇 |
1967年 | 20798篇 |
1966年 | 19437篇 |
排序方式: 共有10000条查询结果,搜索用时 9 毫秒
91.
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92.
93.
94.
95.
C. M. de Bont N. Eerden W. C. Boelens G. J. M. Pruijn 《Clinical and experimental immunology》2020,199(1):1-8
Neutrophils can form neutrophil extracellular traps (NETs) to capture microbes and facilitate their clearance. NETs consist of decondensed chromatin decorated with anti-microbial proteins. Here, we describe the effect of neutrophil proteases on the protein content of NETs. We show that the neutrophil serine proteases degrade several neutrophil proteins associated with NETs. Interestingly, the anti-bacterial proteins associated with NETs, such as myeloperoxidase, calgranulin B and neutrophil elastase (NE), seem to be less susceptible to proteolytic degradation than other NET proteins, such as actin and MNDA. NETs have been proposed to play a role in autoimmune reactions. Our data demonstrate that a large number of the autoepitopes of NET proteins that are recognized by autoantibodies produced by systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) patients are also removed by the proteases. In conclusion, neutrophil serine proteases have a major impact on the NET proteome and the proteolytic changes of NET-associated proteins may counteract autoimmune reactions to NET components. 相似文献
96.
Nicola Flaum Emma J. Crosbie Richard J. Edmondson Miriam J. Smith Dafydd G. Evans 《Clinical genetics》2020,97(1):54-63
Ovarian cancer is the fourth most common cause of cancer-related death in women in the developed world, and one of the most heritable cancers. One of the most significant risk factors for epithelial ovarian cancer (EOC) is a family history of breast and/or ovarian cancer. Combined risk factors can be used in models to stratify risk of EOC, and aid in decisions regarding risk-reduction strategies. Germline pathogenic variants in EOC susceptibility genes including those involved in homologous recombination and mismatch repair pathways are present in approximately 22% to 25% of EOC. These genes are associated with an estimated lifetime risk of EOC of 13% to 60% for BRCA1 variants and 10% to 25% for BRCA2 variants, with lower risks associated with remaining genes. Genome-wide association studies have identified single nucleotide polymorphisms (SNPs) thought to explain an additional 6.4% of the familial risk of ovarian cancer, with 34 susceptibility loci identified to date. However, an unknown proportion of the genetic component of EOC risk remains unexplained. This review comprises an overview of individual genes and SNPs suspected to contribute to risk of EOC, and discusses use of a polygenic risk score to predict individual cancer risk more accurately. 相似文献
97.
Increased arterial stiffness in young normotensive patients with Turner syndrome: associations with vascular biomarkers 下载免费PDF全文
98.
More than just crushing: a prospective pre‐post intervention study to reduce drug preparation errors in patients with feeding tubes 下载免费PDF全文
99.
100.
Adilson Cunha Ferreira Edward Araujo Júnior Wellington P. Martins João Francisco Jordão Antônio Hélio Oliani Simon E. Meagher 《The journal of maternal-fetal & neonatal medicine》2015,28(14):1706-1710
Objective: To assess the quality of images and video clips of fetal central nervous (CNS) structures obtained by ultrasound and transmitted via tele-ultrasound from Brazil to Australia.Methods: In this cross-sectional study, 15 normal singleton pregnant women between 20 and 26 weeks were selected. Fetal CNS structures were obtained by images and video clips. The exams were transmitted in real-time using a broadband internet and an inexpensive video streaming device. Four blinded examiners evaluated the quality of the exams using the Likert scale. We calculated the mean, standard deviation, mean difference, and p values were obtained from paired t tests.Results: The quality of the original video clips was slightly better than that observed by the transmitted video clips; mean difference considering all observers = 0.23 points. In 47/60 comparisons (78.3%; 95% CI?=?66.4–86.9%) the quality of the video clips were judged to be the same. In 182/240 still images (75.8%; 95% CI?=?70.0–80.8%) the scores of transmitted image were considered the same as the original.Conclusion: We demonstrated that long distance tele-ultrasound transmission of fetal CNS structures using an inexpensive video streaming device provided images of subjective good quality. 相似文献