全文获取类型
收费全文 | 1999篇 |
免费 | 162篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 56篇 |
儿科学 | 60篇 |
妇产科学 | 27篇 |
基础医学 | 371篇 |
口腔科学 | 50篇 |
临床医学 | 228篇 |
内科学 | 366篇 |
皮肤病学 | 65篇 |
神经病学 | 106篇 |
特种医学 | 39篇 |
外科学 | 343篇 |
综合类 | 13篇 |
一般理论 | 1篇 |
预防医学 | 166篇 |
眼科学 | 22篇 |
药学 | 120篇 |
中国医学 | 3篇 |
肿瘤学 | 126篇 |
出版年
2022年 | 16篇 |
2021年 | 28篇 |
2020年 | 23篇 |
2019年 | 25篇 |
2018年 | 43篇 |
2017年 | 28篇 |
2016年 | 51篇 |
2015年 | 41篇 |
2014年 | 44篇 |
2013年 | 82篇 |
2012年 | 94篇 |
2011年 | 69篇 |
2010年 | 52篇 |
2009年 | 44篇 |
2008年 | 62篇 |
2007年 | 88篇 |
2006年 | 75篇 |
2005年 | 77篇 |
2004年 | 72篇 |
2003年 | 66篇 |
2002年 | 73篇 |
2001年 | 53篇 |
2000年 | 45篇 |
1999年 | 61篇 |
1998年 | 40篇 |
1997年 | 17篇 |
1996年 | 25篇 |
1995年 | 25篇 |
1994年 | 17篇 |
1993年 | 17篇 |
1992年 | 43篇 |
1991年 | 38篇 |
1990年 | 40篇 |
1989年 | 37篇 |
1988年 | 47篇 |
1987年 | 35篇 |
1986年 | 33篇 |
1985年 | 25篇 |
1984年 | 27篇 |
1983年 | 31篇 |
1982年 | 17篇 |
1981年 | 19篇 |
1979年 | 23篇 |
1978年 | 20篇 |
1976年 | 17篇 |
1973年 | 15篇 |
1971年 | 17篇 |
1970年 | 19篇 |
1969年 | 16篇 |
1967年 | 17篇 |
排序方式: 共有2162条查询结果,搜索用时 31 毫秒
1.
2.
L. Misery E. Weisshaar E. Brenaut A.W.M. Evers F. Huet S. Ständer A. Reich E. Berardesca E. Serra-Baldrich J. Wallengren D. Linder J.W. Fluhr J.C. Szepietowski H. Maibach for the Special Interest Group on sensitive skin of the International Forum for the Study of Itch 《Journal of the European Academy of Dermatology and Venereology》2020,34(2):222-229
The special interest group on sensitive skin of the International Forum for the Study of Itch previously defined sensitive skin as a syndrome defined by the occurrence of unpleasant sensations (stinging, burning, pain, pruritus and tingling sensations) in response to stimuli that normally should not provoke such sensations. This additional paper focuses on the pathophysiology and the management of sensitive skin. Sensitive skin is not an immunological disorder but is related to alterations of the skin nervous system. Skin barrier abnormalities are frequently associated, but there is no cause and direct relationship. Further studies are needed to better understand the pathophysiology of sensitive skin – as well as the inducing factors. Avoidance of possible triggering factors and the use of well-tolerated cosmetics, especially those containing inhibitors of unpleasant sensations, might be suggested for patients with sensitive skin. The role of psychosocial factors, such as stress or negative expectations, might be relevant for subgroups of patients. To date, there is no clinical trial supporting the use of topical or systemic drugs in sensitive skin. The published data are not sufficient to reach a consensus on sensitive skin management. In general, patients with sensitive skin require a personalized approach, taking into account various biomedical, neural and psychosocial factors affecting sensitive skin. 相似文献
3.
4.
Archie L. Overmann DesRaj M. Clark Panagiotis Tsagkozis Rikard Wedin Jonathan A. Forsberg 《Journal of orthopaedic research》2020,38(10):2149-2156
Treatment decisions in patients with metastatic bone disease rely on accurate survival estimation. We developed the original PATHFx models using expensive, proprietary software and now seek to provide a more cost-effective solution. Using open-source machine learning software to create PATHFx version 2.0, we asked whether PATHFx 2.0 could be created using open-source methods and externally validated in two unique patient populations. The training set of a well-characterized, database records of 189 patients and the bnlearn package within R Version 3.5.1 (R Foundation for Statistical Computing), was used to establish a series of Bayesian belief network models designed to predict survival at 1, 3, 6, 12, 18, and 24 months. Each was externally validated in both a Scandinavian (n = 815 patients) and a Japanese (n = 261 patients) data set. Brier scores and receiver operating characteristic curves to assessed discriminatory ability. Decision curve analysis (DCA) evaluated whether models should be used clinically. DCA showed that the model should be used clinically at all time points in the Scandinavian data set. For the 1-month time point, DCA of the Japanese data set suggested to expect better outcomes assuming all patients will survive greater than 1 month. Brier scores for each curve demonstrate that the models are accurate at each time point. Statement of Clinical Significance: we successfully transitioned to PATHFx 2.0 using open-source software and externally validated it in two unique patient populations, which can be used as a cost-effective option to guide surgical decisions in patients with metastatic bone disease. 相似文献
5.
6.
7.
8.
A new approach to the analysis of tissue-implant interaction is presented using rat gluteal muscle as implantation site and using monoclonal antibodies to identify and quantify cells around the implant. The method can be used for comparative studies on biocompatibility. In this methodological investigation, pure titanium (Ti) was studied, revealing an initial response of macrophages, followed by the formation of a fibrous membrane, in which, even at 50 and 70 d, la-expressing cells and suppressor T-lymphocytes were present. 相似文献
9.
The cellulose-binding domain of the major cellobiohydrolase of Trichoderma reesei exhibits true reversibility and a high exchange rate on crystalline cellulose. 总被引:1,自引:0,他引:1 下载免费PDF全文
M Linder T T Teeri 《Proceedings of the National Academy of Sciences of the United States of America》1996,93(22):12251-12255
Cellulose-binding domains (CBDs) bind specifically to cellulose, and form distinct domains of most cellulose degrading enzymes. The CBD-mediated binding of the enzyme has a fundamental role in the hydrolysis of the solid cellulose substrate. In this work we have investigated the reversibility and kinetics of the binding of the CBD from Trichoderma reesei cellobiohydrolase I on microcrystalline cellulose. The CBD was produced in Escherichia coli, purified, and radioactively labeled by reductive alkylation with 3H. Sensitive detection of the labeled CBD allowed more detailed analysis of its behavior than has been possible before, and important novel features were resolved. Binding of the CBD was found to be temperature sensitive, with an increased affinity at lower temperatures. The interaction of the CBD with cellulose was shown to be fully reversible and the CBD could be eluted from cellulose by simple dilution. The rate of exchange measured for the CBD-cellulose interaction compares well with the hydrolysis rate of cellobiohydrolase I, which is consistent with its proposed mode of action as a processive exoglucanase. 相似文献
10.
James W. Geyer Frank Hancock Charles Carrico Marilyn Kirkpatrick James Linder 《Diagnostic cytopathology》1993,9(4):417-422
A new cervical cytology monolayer preparation system called Cyto-Rich was evaluated. Using samples from 557 patients, Cyto-Rich monolayers were compared to matched conventional smears. After conventional smears were prepared and spray fixed, residual exfoliated cells were transferred to preservative fluid. The cell suspensions were gently disaggregated and the epithelial component enriched with gradient centrifugal sedimentation. The batched samples were then placed on the Cyto-Rich work station where slides are automatically prepared and stained. The results demonstrate that Cyto-Rich prepared monolayers are vastly superior to the conventional smears for cell presentation. While the study showed 99% overall concordance, Cyto-Rich improved the detection of low-grade cervical intraepithelial lesions. 相似文献