全文获取类型
收费全文 | 2650495篇 |
免费 | 192344篇 |
国内免费 | 4987篇 |
专业分类
耳鼻咽喉 | 34928篇 |
儿科学 | 87226篇 |
妇产科学 | 72860篇 |
基础医学 | 382181篇 |
口腔科学 | 76549篇 |
临床医学 | 242349篇 |
内科学 | 514245篇 |
皮肤病学 | 59325篇 |
神经病学 | 208367篇 |
特种医学 | 98809篇 |
外国民族医学 | 496篇 |
外科学 | 390045篇 |
综合类 | 59843篇 |
现状与发展 | 6篇 |
一般理论 | 1041篇 |
预防医学 | 208124篇 |
眼科学 | 62292篇 |
药学 | 194387篇 |
13篇 | |
中国医学 | 5872篇 |
肿瘤学 | 148868篇 |
出版年
2019年 | 20906篇 |
2018年 | 29554篇 |
2017年 | 22414篇 |
2016年 | 24646篇 |
2015年 | 28248篇 |
2014年 | 39231篇 |
2013年 | 58472篇 |
2012年 | 80562篇 |
2011年 | 85249篇 |
2010年 | 50116篇 |
2009年 | 47302篇 |
2008年 | 79794篇 |
2007年 | 84920篇 |
2006年 | 85206篇 |
2005年 | 82025篇 |
2004年 | 79128篇 |
2003年 | 75500篇 |
2002年 | 73041篇 |
2001年 | 128304篇 |
2000年 | 131246篇 |
1999年 | 109505篇 |
1998年 | 29808篇 |
1997年 | 26418篇 |
1996年 | 26707篇 |
1995年 | 25437篇 |
1994年 | 23502篇 |
1993年 | 21838篇 |
1992年 | 84317篇 |
1991年 | 82083篇 |
1990年 | 79167篇 |
1989年 | 76543篇 |
1988年 | 70165篇 |
1987年 | 68707篇 |
1986年 | 65053篇 |
1985年 | 61520篇 |
1984年 | 45979篇 |
1983年 | 39607篇 |
1982年 | 22835篇 |
1979年 | 42071篇 |
1978年 | 29843篇 |
1977年 | 25244篇 |
1976年 | 23515篇 |
1975年 | 25006篇 |
1974年 | 30412篇 |
1973年 | 29660篇 |
1972年 | 27685篇 |
1971年 | 25761篇 |
1970年 | 24186篇 |
1969年 | 22722篇 |
1968年 | 21168篇 |
排序方式: 共有10000条查询结果,搜索用时 11 毫秒
141.
Edward R. Westrick MS Allan P. Shapiro PhD Peter E. Nathan PhD John Brick PhD 《Alcoholism, clinical and experimental research》1988,12(4):531-533
The present study demonstrates that alcohol-induced memory impairment can be attenuated by pretreatment with an oral tryptophan supplementation. These results provide support for the role of a brain serotonin deficit in this impairment and highlight the impact a dietary manipulation can have on a complex behavioral process. 相似文献
142.
143.
Summary. In this study, we have examined our records for the isolation of Candida tropicalis from clinical specimens of patients with heterogeneous clinical presentations during the past 5 years. We have found that this species ranks third among all yeasts in frequency of isolation from clinical specimens and that the trend of recovery from the specimens is rising over the years. The isolation rate of C. tropicalis was highest from urine specimens (36%) followed by respiratory specimens (22%). The frequency of isolation of C. tropicalis from vaginal specimens was relatively high (14%), however the trend was declining over the years. In general, the high recovery of Candida tropicalis from clinical specimens of patients with variable disease supports the views of this organism being a major pathogen.
Zusammenfassung. Die Studie basiert auf einer Durchsicht der Patientenarchive der letzten fünf Jahre auf die Isolationshäufigkeit von Candida tropicalis aus klinischen Untersuchungsmaterialien von Patienten mit unterschiedlichen klinischen Krankheitsbildern. Diese Hefeart war die dritthäufigste mit steigender Tendenz über die Jahre. Die Isolierungsrate von C. tropicalis war am höchsten aus Urin (36%), gefolgt von Respirationstrakt-Materialien (22%). Die Isolationshäufigkeit aus dem hinteren Scheidengewölbe war relativ hoch (14%), nahm jedoch mit den jahren ab. Allgemein unterstreicht die hohe Isolationsrate von C. tropicalis aus klinischen Untersuchungsmaterialien die ätiologische Bedeutung dieses Erregers. 相似文献
Zusammenfassung. Die Studie basiert auf einer Durchsicht der Patientenarchive der letzten fünf Jahre auf die Isolationshäufigkeit von Candida tropicalis aus klinischen Untersuchungsmaterialien von Patienten mit unterschiedlichen klinischen Krankheitsbildern. Diese Hefeart war die dritthäufigste mit steigender Tendenz über die Jahre. Die Isolierungsrate von C. tropicalis war am höchsten aus Urin (36%), gefolgt von Respirationstrakt-Materialien (22%). Die Isolationshäufigkeit aus dem hinteren Scheidengewölbe war relativ hoch (14%), nahm jedoch mit den jahren ab. Allgemein unterstreicht die hohe Isolationsrate von C. tropicalis aus klinischen Untersuchungsmaterialien die ätiologische Bedeutung dieses Erregers. 相似文献
144.
P. THOMPSON F. INGLIS D. FINDLAY J. GILCHRIST M. E. T. MCMURDO 《Aging & mental health》1997,1(2):181-183
The Dundee Memory Clinic was established in 1991. This paper reviews the diagnosis of the first 150 attenders and compares the findings with those of other memory clinics. 相似文献
145.
146.
C. R. Irwin T. Myrillas M. Smyth J. Doogan C. Rice S. L. Schor 《Journal of oral pathology & medicine》1998,27(6):255-259
Fibroblasts incorporated within collagen gels induce a cell-mediated contraction of the gel to form a three-dimensional, tissue-like structure by a mechanism thought to mimic wound contraction in vivo . In this study a gel contraction model was used to investigate the ability of fibroblasts derived from adult gingiva, adult skin and fetal skin to organise a collagen matrix. In addition the effects of interleukin-1β (IL-1β) on the contraction process was also investigated. Over the concentration range 5-50 U/ml, IL-1β induced a statistically significant inhibition of gel contraction in all fibroblast cell types ( P <0.05), although fetal fibroblasts appeared least responsive and gingival fibroblasts most responsive to the inhibitory effects of this cytokine. Comparison of gel contraction by the different fibroblast strains indicated that fetal and gingival fibroblasts shared similar contraction kinetics. For the adult skin fibroblasts, three of five strains studied showed significantly diminished levels of gel contraction compared to fetal and gingival cells. This apparent difference in fibroblast phenotype may, at least in part, explain the fetal-like wound healing pattern seen in the oral mucosa. 相似文献
147.
A. HAZIOT I. KATZ G. W. RONG X. Y. LIN J. SILVER & S. M. GOYERT 《Scandinavian journal of immunology》1997,46(3):242-245
Membrane-bound CD14 acts as a receptor for lipopolysaccharide (LPS) on monocytes/macrophages and neutrophils. Studies have suggested that the activation of monocytes/macrophages by the binding of LPS to membrane-bound CD14 may require the association of a signal-transducing molecule with membrane-bound CD14. The observation that non-CD14 expressing cells, such as endothelial cells, can nevertheless be activated by a complex of LPS and a soluble form of CD14 (sCD14) suggests that the receptor for this complex may be identical to the signal transducing molecule associated with membrane-bound CD14. The studies described show that two CD14-specific MoAb are able to block the LPS-induced activation of endothelial cells but do not affect the response of monocytes to LPS. This suggests that the interaction of the sCD14:LPS complex with endothelial cells is distinct from the interaction of membrane-bound CD14 with its putative signal-transducing molecule. 相似文献
148.
This study examines the relationships between patient characteristics and surrogate decision maker characteristics on surrogates' preferences for life-sustaining treatments. Caucasian and African-American caregivers and noncaregivers (n=110) responded to a vignette involving a medical crisis in a hospitalized older man who suffered cardiac arrest, one of the most common causes of death among older Americans. This man was described as either a cognitively intact or moderately demented family member. Participants made decisions regarding cardiopulmonary resuscitation (CPR), CPR and ventilation, and CPR and tube feeding. Analyses followed a 2 (cognitive status) 2 (caregiving status) 2 (racial background) analysis of covariance design, with education and income used as covariates. In general, participants were less likely to initiate life-sustaining treatments in demented patients. Caucasian caregivers were less likely to initiate CPR and ventilation and CPR and tube feeding. Results indicate that characteristics of the patient and the interplay between cultural issues and experience with caregiving affect surrogate judgements regarding life-sustaining treatments. 相似文献
149.
M M Smith J E Thompson D Thomas M Castillo D Carrier S K Mukherji D Gilliam 《AJNR. American journal of neuroradiology》1997,18(2):327
Choristomas, masses of normal tissues in aberrant locations, contain smooth muscle fibers and fibrous tissues. We describe the MR imaging features of two choristomas located in the internal auditory canals and arising from the facial and vestibulocochlear nerves. Both lesions enhanced with contrast material. In one case, enhancement was seen in the geniculate ganglion and greater superficial petrosal nerve. In the other, a medial component enhanced less than the lateral component did. 相似文献
150.
summary The aetiology of denture stomatitis is not clear from the literature. Some studies show its aetiology as Candida albicans, while other reports point out the significance of microorganisms. In this study the existence of C. albicans and microorganisms was investigated in subjects with and without denture stomatitis. The results showed that a combination of C. albicans and microorganisms is more likely to be responsible for denture stomatitis. 相似文献