全文获取类型
收费全文 | 5015篇 |
免费 | 360篇 |
国内免费 | 19篇 |
专业分类
耳鼻咽喉 | 16篇 |
儿科学 | 155篇 |
妇产科学 | 101篇 |
基础医学 | 838篇 |
口腔科学 | 75篇 |
临床医学 | 529篇 |
内科学 | 1138篇 |
皮肤病学 | 101篇 |
神经病学 | 506篇 |
特种医学 | 90篇 |
外科学 | 466篇 |
综合类 | 53篇 |
一般理论 | 1篇 |
预防医学 | 415篇 |
眼科学 | 81篇 |
药学 | 297篇 |
中国医学 | 3篇 |
肿瘤学 | 529篇 |
出版年
2023年 | 31篇 |
2022年 | 58篇 |
2021年 | 114篇 |
2020年 | 71篇 |
2019年 | 120篇 |
2018年 | 113篇 |
2017年 | 72篇 |
2016年 | 91篇 |
2015年 | 124篇 |
2014年 | 152篇 |
2013年 | 226篇 |
2012年 | 370篇 |
2011年 | 391篇 |
2010年 | 201篇 |
2009年 | 181篇 |
2008年 | 310篇 |
2007年 | 326篇 |
2006年 | 327篇 |
2005年 | 314篇 |
2004年 | 306篇 |
2003年 | 323篇 |
2002年 | 261篇 |
2001年 | 72篇 |
2000年 | 73篇 |
1999年 | 80篇 |
1998年 | 68篇 |
1997年 | 54篇 |
1996年 | 47篇 |
1995年 | 44篇 |
1994年 | 30篇 |
1993年 | 27篇 |
1992年 | 44篇 |
1991年 | 44篇 |
1990年 | 36篇 |
1989年 | 33篇 |
1988年 | 23篇 |
1987年 | 25篇 |
1986年 | 20篇 |
1985年 | 22篇 |
1984年 | 20篇 |
1983年 | 10篇 |
1982年 | 10篇 |
1981年 | 11篇 |
1980年 | 10篇 |
1979年 | 15篇 |
1978年 | 10篇 |
1977年 | 8篇 |
1974年 | 9篇 |
1972年 | 9篇 |
1970年 | 10篇 |
排序方式: 共有5394条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
5.
Stanford''s two decades of success in linking medical informatics and health services research in both training and investigational activities reflects advantageous geography and history as well as natural synergies in the two areas. Health services research and medical informatics at Stanford have long shared a quantitative, analytic orientation, along with linked administration, curriculum, and clinical activities. Both the medical informatics and the health services research curricula draw on diverse course offerings throughout the university, and both the training and research overlap in such areas as outcomes research, large database analysis, and decision analysis/decision support. The Stanford experience suggests that successful integration of programs in medical informatics and health services research requires areas of overlapping or synergistic interest and activity among the involved faculty and, hence, in time, among the students. This is enhanced by a mixture of casual and structured contact among students from both disciplines, including social interactions. The challenges to integration are how to overcome any geographic separation that may exist in a given institution; the proper management of relationships with those sub-areas of medical informatics that have less overlap with health services research; and the need to determine how best to exploit opportunities for collaboration that naturally occur.Training in medical informatics and health services research has been closely linked at Stanford University for almost two decades. Although the close linkage was deliberate, it was facilitated by historical circumstances, in particular the common academic structures in which both programs arose. In this paper, we describe some of that rationale and history, identifying the areas of overlap that we have pursued in coordinating the training opportunities for graduate students and fellows in both areas of study. As we shall note, the synergies have been great, and in some cases trainees have collaborated closely on research while also taking some of the same courses. We believe that these interactions can be a model for the design of training programs that encourage scholarly interactions between medical informatics and health services research. Although our initial charge was to describe both the successes and failures in integrating the programs, we found that we could not identify any outright failures and that it would be better to delineate the complexities and challenges that we have faced in bringing together these two disciplines. 相似文献
6.
Alessia Pascale Marialaura Amadio Stefano Govoni Fiorenzo Battaini 《Pharmacological research》2007,55(6):560-569
The brain represents the primary centre for the regulation and control of all our body activities, receiving and interpreting sensory impulses and transmitting information to the periphery. Most importantly, it is also the seat of consciousness, thought, emotion and especially memory, being in fact able to encode, store and recall any information. Memory is really what makes possible so many of our complex cognitive functions, including communication and learning, and surely without memory, life would lose all of its glamour and purpose. Age-associated mental impairment can range in severity from forgetfulness at the border with pathology to dementia, such as in Alzheimer's disease. In recent years, one of the most relevant observations of research on brain aging relates to data indicating that age-related cognitive decline is not only due to neuronal loss, as previously thought; instead, scientists now believe that age-associated functional changes have more to do with the dysfunctions occurring over time. Within this context a prominent role is certainly played by signal transduction cascades which guarantee neuronal cell to elaborate coordinated responses to the multiple signals coming from the outside and to adapt itself to the environmental changes and requests. This review will focus the attention on protein kinase C pathway, with a particular interest on its activation process, and on the role of protein-lipid and protein-protein interactions to selectively localize the cellular responses. Furthermore, information is emerging and will be discussed on the possibility of mRNA stabilization through PKC activation. This review will also approach the issue on how alterations of these molecular cascades may have implications in physiological and pathological brain aging, such as Alzheimer's disease. 相似文献
7.
Pascale Jolliet Stéphane Nion Gwena?lle Allain-Veyrac L Tilloy-Fenart Dorothée Vanuxeem Vincent Berezowski Roméo Cecchelli 《Pharmacological research》2007,56(1):11-17
PURPOSE: The objective of the current study was to determine the ability of some antiemetic compounds to cross the blood-brain barrier (BBB) and thereby to determine possible side effects of compounds for the central nervous system (CNS). METHODS: We compared the brain penetration of some antiemetic compounds using an in vitro BBB model consisting in brain capillary endothelial cells co-cultured with primary rat glial cells. RESULTS: This study clearly demonstrated that the metopimazine metabolite, metopimazine acid, has a very low brain penetration, lower than metopimazine and even less than the other antiemetic compounds tested in this study. CONCLUSIONS: The poor brain penetration of metopimazine acid, metopimazine biodisponible form, seems very likely related to the clinically observed difference in therapeutic and safety profile. 相似文献
8.
外科医生和手术室人员经常接触手术设备产生的烟气,病人也会暴露于烟气中,特别是腹腔镜手术中产生的烟气滞留于腹腔内这一密闭空间并被吸收.这些烟气是一种与香烟烟气相似的毒性物质,然而对这种毒性物质的影响还未引起足够重视.应该采取必要措施尽可能减少手术中烟气的不良影响. 相似文献
9.
Roland D Chapurlat Monique Arlot Brigitte Burt-Pichat Pascale Chavassieux Jean Paul Roux Nathalie Portero-Muzy Pierre D Delmas 《Journal of bone and mineral research》2007,22(10):1502-1509
We sought whether microdamage could rise in postmenopausal osteoporotic women on long-term bisphosphonates, as suggested by recent animal studies. We found few microcracks in iliac bone biopsies, despite a marked reduction in bone turnover. INTRODUCTION: Animal studies suggest that bisphosphonates (BPs) could increase microdamage frequency in a dose-dependent manner, caused by excessively suppressed bone turnover. However, there is limited data in humans receiving BP therapeutic doses for >3 yr. MATERIALS AND METHODS: We measured microcrack frequency and histomorphometry parameters on transiliac bone biopsies in 50 postmenopausal osteoporotic women (mean age = 68 yr) who had received BP therapy (3 on intravenous pamidronate, 37 on oral alendronate, and 10 on oral risedronate) for at least 3 yr (mean treatment duration = 6.5 yr). We compared these results with transiliac bone biopsies obtained from 12 cadavers. We used bulk staining with green calcein as a fluorochrome. The microcracks were quantified in three 100-microm-thick sections using optic microscopy and were confirmed by laser confocal microscopy. Microcrack frequency (number of microcracks/mm2 of bone tissue) was compared between treated women and controls using nonparametric tests. We also explored predictors of microcrack frequency, including age, duration of BP therapy, and activation frequency. RESULTS: Among treated women, cancellous bone microcrack frequency was low (mean, 0.13 microcracks/mm2) and did not differ significantly from that observed in controls (0.05 microcracks/mm2; p = 0.59). Of note, 54% of the treated women and 58% of the controls had no observable microcracks. There was no association between microcrack frequency and the duration of BP therapy (for microcracks/mm2 and duration, Spearman r = 0.04, p = 0.80) and between patients' ages and the number of microcracks (Spearman r = -0.09, p = 0.61). Although bone remodeling parameters were suppressed in treated women, we found no relationship between microcrack density and activation frequency (Spearman r = -0.003, p = 0.99). Also, microcrack frequency was not increased in women with prevalent vertebral fracture compared with those without fractures. CONCLUSIONS: Among postmenopausal osteoporotic women on long-term BPs, microcrack frequency in the iliac bone is low, despite a marked reduction of bone turnover. 相似文献
10.
Patrizio Pascale Martin Fromer 《Journal of the American College of Cardiology》2007,49(1):124-5; author reply 125