全文获取类型
收费全文 | 21842篇 |
免费 | 1795篇 |
国内免费 | 38篇 |
专业分类
耳鼻咽喉 | 166篇 |
儿科学 | 817篇 |
妇产科学 | 589篇 |
基础医学 | 2732篇 |
口腔科学 | 293篇 |
临床医学 | 2417篇 |
内科学 | 3935篇 |
皮肤病学 | 368篇 |
神经病学 | 2240篇 |
特种医学 | 416篇 |
外国民族医学 | 5篇 |
外科学 | 2605篇 |
综合类 | 259篇 |
一般理论 | 71篇 |
预防医学 | 3132篇 |
眼科学 | 572篇 |
药学 | 1467篇 |
1篇 | |
中国医学 | 40篇 |
肿瘤学 | 1550篇 |
出版年
2024年 | 36篇 |
2023年 | 271篇 |
2022年 | 404篇 |
2021年 | 963篇 |
2020年 | 585篇 |
2019年 | 814篇 |
2018年 | 921篇 |
2017年 | 656篇 |
2016年 | 677篇 |
2015年 | 744篇 |
2014年 | 975篇 |
2013年 | 1270篇 |
2012年 | 1780篇 |
2011年 | 1821篇 |
2010年 | 935篇 |
2009年 | 762篇 |
2008年 | 1322篇 |
2007年 | 1368篇 |
2006年 | 1138篇 |
2005年 | 1076篇 |
2004年 | 977篇 |
2003年 | 899篇 |
2002年 | 660篇 |
2001年 | 204篇 |
2000年 | 205篇 |
1999年 | 209篇 |
1998年 | 149篇 |
1997年 | 109篇 |
1996年 | 73篇 |
1995年 | 89篇 |
1994年 | 74篇 |
1993年 | 80篇 |
1992年 | 122篇 |
1991年 | 122篇 |
1990年 | 100篇 |
1989年 | 97篇 |
1988年 | 87篇 |
1987年 | 84篇 |
1986年 | 76篇 |
1985年 | 73篇 |
1984年 | 58篇 |
1983年 | 41篇 |
1982年 | 36篇 |
1981年 | 49篇 |
1980年 | 30篇 |
1979年 | 51篇 |
1978年 | 41篇 |
1977年 | 40篇 |
1974年 | 35篇 |
1972年 | 42篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
Kevin G Becker Insong J Lee James W Nagle Rachel D Canning Ameer M Gado Rosarelis Torres Mihael H Polymeropoulos Paul T Massa WilliamE Biddison Paul D Drew 《International journal of developmental neuroscience》1997,15(7):73
We describe a novel human zinc finger cNDA, C2H2-171. This cDNA represents an mRNA which encodes a protein of 484 amino acids and a calculated molecular weight of 54 kD. Four zinc finger-like domains are found in the C-terminal end of the protein. At the N-terminus, C2H2-171 contains a POZ/tramtrack-like domain similar to that found in the tumor associated zinc finger proteins LAZ-3/BCL-6 and PLZ-F, as well as in non-zinc finger proteins. C2H2-171 RNA is preferentially expressed in the brain, and increases during the course of murine development, with maximal expression in the adult. C2H2-171 RNA is differentially expressed in brain regions, with the highest level of expression in the cerebellum. C2H2-171 RNA was expressed at high levels in primary cerebellar granule cell neurons compared to astrocytes. The gene encoding C2H2-171 is highly conserved in vertebrates, and maps to the terminus of human chromosome 1 (1q44-ter). This chromosomal location is associated with a number of cytogenetic aberrations including those involving brain developmental anomalies and tumorigenesis. These data suggest that C2H2-171 may play an important role in vertebrate brain development and function. 相似文献
42.
Ladenstein Ruth; Pearce Rachel; Hartmann Olivier; Patte Catherine; Goldstone Tony; Philip Thierry 《Blood》1997,90(8):2921-2930
43.
44.
45.
Bile acid receptors in colorectal cancer 总被引:4,自引:0,他引:4
Bile acids are thought to be involved in both the aetiology and development of colorectal cancer. In this study the existence of specific bile acid receptor proteins has been postulated. A receptor assay which involved labelling with 14C-deoxycholic acid was performed as well as autoradiography using 3H-deoxycholic acid. In an initial study resected colorectal cancer and adjacent histologically normal colorectal mucosa from 39 patients were studied, as were samples of normal gastric mucosa, cancers and benign colorectal tumours. Specific receptors to deoxycholic acid were detected in 12 (30.8 per cent) of the colorectal cancers, but in only 1 (2.6 per cent) of the samples from normal colorectal mucosa (X2 = 11.16, P less than 0.005). No deoxycholic acid receptors were detected in any other tissue studied. Autoradiographs of colorectal cancers showed binding of 3H-deoxycholic acid in receptor-positive tumour tissue. These findings might provide some explanation for the evidence linking bile acids with the disease. 相似文献
46.
Gordon Grant Paul Ramcharan Margaret Flynn 《Journal of Applied Research in Intellectual Disabilities》2007,20(6):563-575
Aim This paper seeks to illumine how families with children and adult members with intellectual disabilities manage to manifest a buoyant and durable capacity over time. It is therefore concerned centrally with the idea of resilience. Method Drawing from diverse theoretical literatures from child development and protection and gerontology, the paper begins with a review of constructions of resilience. In an attempt to assess where there seems to be support for resilience in families, the core of the paper tests empirical evidence about positive experiences of families supporting children and adults with intellectual disabilities against the theoretical literature on resilience. Result and Conclusions The findings are used to suggest conditions under which resilience is produced and maintained, and to identify emergent elements of a psycho‐social model of resilience in families with children and adult members with intellectual disabilities. 相似文献
47.
Rony Gelman Lei Jiang Yunling E Du M Elena Martinez-Perez John T Flynn Michael F Chiang 《Journal of AAPOS》2007,11(6):532-540
PURPOSE: To measure accuracy of plus disease diagnosis by recognized experts in retinopathy of prematurity (ROP), and to conduct a pilot study examining performance of a computer-based image analysis system, Retinal Image multiScale Analysis (RISA). METHODS: Twenty-two ROP experts independently interpreted a set of 34 wide-angle retinal images for presence of plus disease. A reference standard diagnosis based on expert consensus was defined for each image. Images were analyzed by the computer-based system using individual and linear combinations of system parameters for arterioles and venules: integrated curvature (IC), diameter, and tortuosity index (TI). Sensitivity, specificity, and receiver operating characteristic areas under the curve (AUC) for plus disease diagnosis compared with the reference standard were determined for each expert, as well as for the computer-based system. RESULTS: Expert sensitivity ranged from 0.308 to 1.000, specificity ranged from 0.571 to 1.000, and AUC ranged from 0.784 to 1.000. Among individual computer system parameters, venular IC had highest AUC (0.853). Among all computer system parameters, the linear combination of arteriolar IC, arteriolar TI, venular IC, venular diameter, and venular TI had highest AUC (0.967), which was greater than that of 18 (81.8%) of 22 experts. CONCLUSIONS: Accuracy of ROP experts for plus disease diagnosis is imperfect. A computer-based image analysis system has potential to diagnose plus disease with high accuracy. Further research involving RISA system parameter cut-off values from this study are required to fully validate performance of this computer-based system compared with that of human experts. 相似文献
48.
Suresh Kumar Masilamani Annamalai Rachel Buckingham John Cashman 《Journal of children's orthopaedics》2007,1(2):107-113
The treatment of Legg-Calvé-Perthes disease remains controversial. The aim of this survey was to ascertain the current management
strategies of this condition amongst UK paediatric orthopaedic surgeons, with particular regard to containment procedures
in the fragmentation phase. Questionnaires were distributed at the January 2006 meeting of the British Society for Children’s
Orthopaedic Surgery (BSCOS) and was posted to all absent members. The results showed a great deal of variability not only
in the treatment of Perthes disease, but also in the decision-making processes. Consideration must now be given to a carefully
constructed national multi-centre prospective randomised controlled study into the optimum management of this disease 相似文献
49.
Rachel M Massey Oliver J Warren Michal Szczeklik Sophie Wallace Daniel R Leff John Kokotsakis Ara Darzi Thanos Athanasiou 《Journal of cardiothoracic surgery》2007,2(1):26-9
The use of a skeletonized internal thoracic artery in coronary artery bypass graft surgery has been shown to confer certain
advantages over a traditional pedicled technique, particularly in certain patient groups. Recent reports indicate that radial
and gastroepiploic arteries can also be harvested using a skeletonized technique. The aim of this study is to systematically
review the available evidence regarding the use of skeletonized radial and gastroepiploic arteries within coronary artery
bypass surgery, focusing specifically on it's effect on conduit length and flow, levels of endothelial damage, graft patency
and clinical outcome. Four electronic databases were systematically searched for studies reporting the utilisation of the
skeletonization technique within coronary revascularisation surgery in humans. Reference lists of all identified studies were
checked for any missing publications. There appears to be some evidence that skeletonization may improve angiographic patency,
when compared with pedicled vessels in the short to mid-term. We have found no suggestion of increased complication rates
or increased operating time. Skeletonization may increase the length of the conduit, and the number of sequential graft sites,
but no clear clinical benefits are apparent. Our study suggests that there is not enough high quality or consistent evidence
to currently advocate the application of this technique to radial or gastroepiploic conduits ahead of a traditional pedicled
technique. 相似文献
50.