全文获取类型
收费全文 | 613篇 |
免费 | 45篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 7篇 |
儿科学 | 9篇 |
妇产科学 | 13篇 |
基础医学 | 79篇 |
口腔科学 | 5篇 |
临床医学 | 63篇 |
内科学 | 121篇 |
皮肤病学 | 18篇 |
神经病学 | 52篇 |
特种医学 | 41篇 |
外科学 | 51篇 |
综合类 | 4篇 |
一般理论 | 1篇 |
预防医学 | 107篇 |
药学 | 36篇 |
肿瘤学 | 52篇 |
出版年
2023年 | 3篇 |
2022年 | 3篇 |
2021年 | 12篇 |
2020年 | 5篇 |
2019年 | 5篇 |
2018年 | 15篇 |
2017年 | 8篇 |
2016年 | 16篇 |
2015年 | 14篇 |
2014年 | 12篇 |
2013年 | 20篇 |
2012年 | 42篇 |
2011年 | 54篇 |
2010年 | 20篇 |
2009年 | 10篇 |
2008年 | 33篇 |
2007年 | 30篇 |
2006年 | 43篇 |
2005年 | 42篇 |
2004年 | 53篇 |
2003年 | 59篇 |
2002年 | 52篇 |
2001年 | 8篇 |
2000年 | 8篇 |
1999年 | 12篇 |
1998年 | 9篇 |
1997年 | 10篇 |
1996年 | 2篇 |
1994年 | 3篇 |
1993年 | 3篇 |
1992年 | 3篇 |
1990年 | 4篇 |
1988年 | 3篇 |
1987年 | 3篇 |
1986年 | 3篇 |
1983年 | 4篇 |
1982年 | 4篇 |
1974年 | 2篇 |
1964年 | 1篇 |
1963年 | 1篇 |
1962年 | 1篇 |
1960年 | 1篇 |
1954年 | 1篇 |
1945年 | 1篇 |
1931年 | 2篇 |
1930年 | 2篇 |
1928年 | 2篇 |
1925年 | 1篇 |
1923年 | 2篇 |
1918年 | 1篇 |
排序方式: 共有659条查询结果,搜索用时 15 毫秒
11.
Au R Seshadri S Wolf PA Elias M Elias P Sullivan L Beiser A D'Agostino RB 《Experimental aging research》2004,30(4):333-358
A previous publication presented normative data on neuropsychological tests stratified by age, gender, and education based on the Original Cohort of the Framingham Heart Study. Many contemporary investigations include subject samples with higher levels of education, a factor known to affect cognitive performance. Secular change in education prompted the reexamination of norms in the children of the Original Cohort. The study population consisted of 853 men and 988 women from the Offspring Study, free of clinical neurological disease, who underwent a neuropsychological examination, which included tests given to their parents in 1974 to 1976 as well as additional newer tests to provide a more comprehensive battery. The Offspring population overall was more evenly distributed by gender and better educated. Their performance on cognitive tests was superior to that of the Original Cohort. Multivariable analyses revealed that more years of education explained only a part of the cohort differences. These findings suggest that continued surveillance of each generation is necessary to document the impact that unique social and economic variables have on cognitive function. Here, the authors provide updated normative data. 相似文献
12.
Cobin RH 《Metabolic syndrome and related disorders》2005,3(3):259-269
Polycystic ovarian syndrome (PCOS) is the most frequent endocrine disorder of reproductive age women, affecting an estimated 8-10% of all women in this age group or approximately six million women. Further, women with PCOS continue to manifest the metabolic alterations inherent in the insulin resistance syndrome after menopause, rendering them more susceptible to type 2 diabetes and cardiovascular disease. Aging and obesity further contribute to these risks. Since estrogen-containing therapy is commonly used for menstrual regulation in premenopausal women with PCOS, it is important to evaluate the possible consequences of hormonal therapy on subsequent metabolic and cardiovascular risk. In postmenopausal women, a consensus regarding the appropriate role of estrogen replacement therapy is currently in evolution. By examining the effects of estrogen with or without progesterone on insulin resistance, insight may be gained about the risk/benefit ratio of this therapy in the subset of women with insulin resistance, PCOS, and type 2 diabetes. The goal of this review, then, is to examine the known effects of estrogen on insulin sensitivity and its implications for cardiovascular and metabolic risk. 相似文献
13.
Herpes simplex virus type 2 infection as a risk factor for human immunodeficiency virus acquisition in men who have sex with men 总被引:4,自引:0,他引:4
Renzi C Douglas JM Foster M Critchlow CW Ashley-Morrow R Buchbinder SP Koblin BA McKirnan DJ Mayer KH Celum CL 《The Journal of infectious diseases》2003,187(1):19-25
The association of human immunodeficiency virus (HIV) acquisition with herpes simplex virus type 2 (HSV-2) was assessed among men who have sex with men (MSM) in a nested case-control study of 116 case subjects who seroconverted to HIV during follow-up and 342 control subjects who remained HIV seronegative, frequency-matched by follow-up duration and report of HIV-infected sex partner and unprotected anal sex. The baseline HSV-2 seroprevalence was higher among case (46%) than control (34%) subjects (P=.03); the HSV-2 seroincidence was 7% versus 4% (P=.3). Only 15% of HSV-2-infected MSM reported herpes outbreaks in the past year. HIV acquisition was associated with prior HSV-2 infection (odds ratio [OR], 1.8; 95% confidence interval [CI], 1.1-2.9), reporting >12 sex partners (OR, 2.9; 95% CI, 1.4-6.3), and reporting fewer herpes outbreaks in the past year (OR, 0.3; 95% CI, 0.1-0.8). HSV-2 increases the risk of HIV acquisition, independent of recognized herpes lesions and behaviors reflecting potential HIV exposure. HSV-2 suppression with antiviral therapy should be evaluated as an HIV prevention strategy among MSM. 相似文献
14.
Management of recurrent and persistent metastatic lymph nodes in well‐differentiated thyroid cancer: A multifactorial decision‐making guide for the thyroid cancer care collaborative
下载免费PDF全文
![点击此处可从《Head & neck》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Mark L. Urken MD Mira Milas MD Gregory W. Randolph MD Ralph Tufano MD Donald Bergman MD Victor Bernet MD Elise M. Brett MD James D. Brierley MD Rhoda Cobin MD Gerard Doherty MD Joshua Klopper MD Stephanie Lee MD PhD Josef Machac MD Jeffrey I. Mechanick MD Lisa A. Orloff MD Douglas Ross MD Robert C. Smallridge MD David J Terris MD Jason B Clain BS Michael Tuttle MD 《Head & neck》2015,37(4):605-614
15.
16.
17.
18.
19.
A large body of behavioural research has used the cued task‐switching paradigm to characterize the nature of trial‐by‐trial preparatory adjustments that enable fluent task implementation when demands on cognitive flexibility are high. This work reviews the growing number of fMRI studies on the same topic, mostly focusing on the central hypothesis that preparatory adjustments should be indicated by enhanced prefrontal and parietal BOLD activation in task switch when compared with task repeat trials under conditions that enable advance task preparation. The evaluation of this straight‐forward hypothesis reveals surprisingly heterogeneous results regarding both the precise localization and the very existence of switch‐related preparatory activation. Explanations for these inconsistencies are considered on two levels. First, we discuss methodological issues regarding (i) the possible impact of different fMRI‐specific experimental design modifications and (ii) statistical uncertainty in the context of massively multivariate imaging data. Second, we discuss explanations related to the multidimensional nature of task preparation itself. Specifically, the precise localization and the size of switch‐related preparatory activation might depend on the differential interplay of hierarchical control via abstract task goals and attentional versus action‐directed preparatory processes. We argue that different preparatory modes can be adopted relying either on advance goal activation alone or on the advance resolution of competition within action sets or attentional sets. Importantly, while either mode can result in a reduction of behavioral switch cost, only the latter two are supposed to be associated with enhanced switch versus repeat BOLD activation in prepared trial conditions. Hum Brain Mapp, 2013. © 2011 Wiley Periodicals, Inc. 相似文献
20.