全文获取类型
收费全文 | 1091686篇 |
免费 | 75456篇 |
国内免费 | 1915篇 |
专业分类
耳鼻咽喉 | 14460篇 |
儿科学 | 33426篇 |
妇产科学 | 29647篇 |
基础医学 | 150408篇 |
口腔科学 | 27505篇 |
临床医学 | 92788篇 |
内科学 | 205175篇 |
皮肤病学 | 18418篇 |
神经病学 | 91793篇 |
特种医学 | 45352篇 |
外国民族医学 | 171篇 |
外科学 | 172842篇 |
综合类 | 27726篇 |
现状与发展 | 3篇 |
一般理论 | 333篇 |
预防医学 | 90567篇 |
眼科学 | 23896篇 |
药学 | 77644篇 |
中国医学 | 2249篇 |
肿瘤学 | 64654篇 |
出版年
2018年 | 32095篇 |
2017年 | 25472篇 |
2016年 | 29399篇 |
2015年 | 10105篇 |
2014年 | 13765篇 |
2013年 | 19868篇 |
2012年 | 32979篇 |
2011年 | 48904篇 |
2010年 | 34685篇 |
2009年 | 26730篇 |
2008年 | 46205篇 |
2007年 | 51771篇 |
2006年 | 26892篇 |
2005年 | 28764篇 |
2004年 | 29605篇 |
2003年 | 30217篇 |
2002年 | 26823篇 |
2001年 | 36428篇 |
2000年 | 37339篇 |
1999年 | 31347篇 |
1998年 | 9723篇 |
1997年 | 9035篇 |
1996年 | 8761篇 |
1995年 | 8297篇 |
1994年 | 8030篇 |
1992年 | 26856篇 |
1991年 | 26330篇 |
1990年 | 25857篇 |
1989年 | 24870篇 |
1988年 | 23386篇 |
1987年 | 23045篇 |
1986年 | 21892篇 |
1985年 | 21260篇 |
1984年 | 16511篇 |
1983年 | 14107篇 |
1982年 | 8977篇 |
1981年 | 8248篇 |
1979年 | 16854篇 |
1978年 | 12194篇 |
1977年 | 10217篇 |
1976年 | 9406篇 |
1975年 | 10170篇 |
1974年 | 12694篇 |
1973年 | 12166篇 |
1972年 | 11564篇 |
1971年 | 10698篇 |
1970年 | 10268篇 |
1969年 | 9963篇 |
1968年 | 8939篇 |
1967年 | 8243篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
82.
Michael W. Manning Yi-Ju Li Dean Linder John C. Haney Yi-Hung Wu Mihai V. Podgoreanu Madhav Swaminathan Jacob N. Schroder Carmelo A. Milano Ian J. Welsby Mark Stafford-Smith Kamrouz Ghadimi 《Journal of cardiothoracic and vascular anesthesia》2021,35(5):1310-1318
- Download : Download high-res image (215KB)
- Download : Download full-size image
83.
Erik de Bakker Mirthe A. M. van der Putten Martijn W. Heymans Sander W. Spiekstra Taco Waaijman Liselotte Butzelaar Vera L. Negenborn Vivian K. Beekman Erman O. Akpinar Thomas Rustemeyer Frank B. Niessen Susan Gibbs 《Experimental dermatology》2021,30(1):169-178
Unpredictable hypertrophic scarring (HS) occurs after approximately 35% of all surgical procedures and causes significant physical and psychological complaints. Parallel to the need to understanding the mechanisms underlying HS formation, a prognostic tool is needed. The objective was to determine whether (systemic) immunological differences exist between patients who develop HS and those who develop normotrophic scars (NS) and to assess whether those differences can be used to identify patients prone to developing HS. A prospective cohort study with NS and HS groups in which (a) cytokine release by peripheral blood mononuclear cells (PBMC) and (b) the irritation threshold (IT) after an irritant (sodium lauryl sulphate) patch test was evaluated. Univariate regression analysis of PBMC cytokine secretion showed that low MCP‐1, IL‐8, IL‐18 and IL‐23 levels have a strong correlation with HS (P < .010‐0.004; AUC = 0.790‐0.883). Notably, combinations of two or three cytokines (TNF‐a, MCP‐1 and IL‐23; AUC: 0.942, Nagelkerke R2: 0.727) showed an improved AUC indicating a better correlation with HS than single cytokine analysis. These combination models produce good prognostic results over a broad probability range (sensitivity: 93.8%, specificity 86.7%, accuracy 90,25% between probability 0.3 and 0.7). Furthermore, the HS group had a lower IT than the NS group and an accuracy of 68%. In conclusion, very fundamental immunological differences exist between individuals who develop HS and those who do not, whereas the cytokine assay forms the basis of a predictive prognostic test for HS formation, the less invasive, easily performed irritant skin patch test is more accessible for daily practice. 相似文献
84.
85.
Many studies identify the risk factors for joining street gangs, but few explore disengagement. This article provides a systematic review of the factors which contribute to disengagement from gangs. Understanding this area is of paramount importance to developing policy and guiding practitioners working with this population, given the impact this lifestyle has on gang members and society as a whole. Seven academic databases, reference lists of relevant publications, an online search engine and a government database were used to identify relevant studies. Inclusion and exclusion criteria and quality assessment methods were employed. Data were then extracted and synthesised. Of 2515 citations, seven were found to have methodological rigour. The findings suggest there is not one definitive reason for gang exit but rather that multiple factors contribute. Variability was found in the quality scores. The limitations of this review are discussed, along with clinical implications and suggestions for future research. 相似文献
86.
87.
Sarah E. Henderson Shana A. Hall Jessica M. Callegari James A. Desjardins Sidney J. Segalowitz Karen L. Campbell 《Psychophysiology》2022,59(1):e13947
Recent work suggests that while voluntary episodic memory declines with age, involuntary episodic memory, which comes to mind spontaneously without intention, remains relatively intact. However, the neurophysiology underlying these differences has yet to be established. The current study used electroencephalography (EEG) to investigate voluntary and involuntary retrieval in older and younger adults. Participants first encoded sounds, half of which were paired with pictures, the other half unpaired. EEG was then recorded as they listened to the sounds, with participants in the involuntary group performing a sound localization cover task, and those in the voluntary group additionally attempting to recall the associated pictures. Participants later reported which sounds brought the paired picture to mind during the localization task. Reaction times on the localization task were slower for voluntary than involuntary retrieval and for paired than unpaired sounds, possibly reflecting increased attentional demands of voluntary retrieval and interference from reactivation of the associated pictures respectively. For the EEG analyses, young adults showed greater alpha event-related desynchronization (ERD) during voluntary than involuntary retrieval at frontal and occipital sites, while older adults showed pronounced alpha ERD regardless of intention. Additionally, older adults showed greater ERD for paired than unpaired sounds at occipital sites, likely reflecting visual reactivation of the associated pictures. Young adults did not show this alpha ERD memory effect. Taken together, these data suggest that involuntary memory is largely preserved with age, but this may be due to older adults' greater recruitment of top-down control even when demand for such control is limited. 相似文献
88.
van der Heijden Amber A. W. A. de Bruijne Martine C. Nijpels Giel Hugtenburg Jacqueline G. 《International journal of clinical pharmacy》2019,41(4):963-971
International Journal of Clinical Pharmacy - Background Drug-related problems (DRP) following hospital discharge may cause morbidity, mortality and hospital re-admissions. It is unclear whether a... 相似文献
89.
90.