全文获取类型
收费全文 | 4466928篇 |
免费 | 356606篇 |
国内免费 | 14928篇 |
专业分类
耳鼻咽喉 | 61574篇 |
儿科学 | 142800篇 |
妇产科学 | 116531篇 |
基础医学 | 682251篇 |
口腔科学 | 120475篇 |
临床医学 | 409375篇 |
内科学 | 813125篇 |
皮肤病学 | 109433篇 |
神经病学 | 379911篇 |
特种医学 | 173237篇 |
外国民族医学 | 761篇 |
外科学 | 673625篇 |
综合类 | 123393篇 |
现状与发展 | 24篇 |
一般理论 | 2839篇 |
预防医学 | 369729篇 |
眼科学 | 104439篇 |
药学 | 316712篇 |
26篇 | |
中国医学 | 12160篇 |
肿瘤学 | 226042篇 |
出版年
2021年 | 57552篇 |
2020年 | 36682篇 |
2019年 | 60065篇 |
2018年 | 76202篇 |
2017年 | 58012篇 |
2016年 | 64307篇 |
2015年 | 77150篇 |
2014年 | 112013篇 |
2013年 | 178284篇 |
2012年 | 135267篇 |
2011年 | 141407篇 |
2010年 | 129945篇 |
2009年 | 130496篇 |
2008年 | 126329篇 |
2007年 | 134755篇 |
2006年 | 143185篇 |
2005年 | 137198篇 |
2004年 | 137770篇 |
2003年 | 127366篇 |
2002年 | 116058篇 |
2001年 | 167593篇 |
2000年 | 162537篇 |
1999年 | 149253篇 |
1998年 | 72328篇 |
1997年 | 68112篇 |
1996年 | 66047篇 |
1995年 | 61395篇 |
1994年 | 55319篇 |
1993年 | 51297篇 |
1992年 | 106925篇 |
1991年 | 101630篇 |
1990年 | 97480篇 |
1989年 | 95049篇 |
1988年 | 87365篇 |
1987年 | 85567篇 |
1986年 | 80440篇 |
1985年 | 78602篇 |
1984年 | 65670篇 |
1983年 | 58438篇 |
1982年 | 47437篇 |
1981年 | 44100篇 |
1980年 | 41289篇 |
1979年 | 55269篇 |
1978年 | 44918篇 |
1977年 | 40107篇 |
1976年 | 36967篇 |
1975年 | 36910篇 |
1974年 | 39728篇 |
1973年 | 37868篇 |
1972年 | 35475篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
891.
892.
893.
Adilson Cunha Ferreira Edward Araujo Júnior Wellington P. Martins João Francisco Jordão Antônio Hélio Oliani Simon E. Meagher 《The journal of maternal-fetal & neonatal medicine》2015,28(14):1706-1710
Objective: To assess the quality of images and video clips of fetal central nervous (CNS) structures obtained by ultrasound and transmitted via tele-ultrasound from Brazil to Australia.Methods: In this cross-sectional study, 15 normal singleton pregnant women between 20 and 26 weeks were selected. Fetal CNS structures were obtained by images and video clips. The exams were transmitted in real-time using a broadband internet and an inexpensive video streaming device. Four blinded examiners evaluated the quality of the exams using the Likert scale. We calculated the mean, standard deviation, mean difference, and p values were obtained from paired t tests.Results: The quality of the original video clips was slightly better than that observed by the transmitted video clips; mean difference considering all observers = 0.23 points. In 47/60 comparisons (78.3%; 95% CI?=?66.4–86.9%) the quality of the video clips were judged to be the same. In 182/240 still images (75.8%; 95% CI?=?70.0–80.8%) the scores of transmitted image were considered the same as the original.Conclusion: We demonstrated that long distance tele-ultrasound transmission of fetal CNS structures using an inexpensive video streaming device provided images of subjective good quality. 相似文献
894.
895.
896.
897.
898.
899.
Clinical Spectrum of Capillary Malformation–Arteriovenous Malformation Syndrome Presenting to a Pediatric Dermatology Practice: A Retrospective Study 下载免费PDF全文
Nicole A. Weitz M.D. Christine T. Lauren M.D. Gerald G. Behr M.D. June K. Wu M.D. Jessica J. Kandel M.D. Philip M. Meyers M.D. Sally Sultan M.D. Kwame Anyane‐Yeboa M.D. Kimberly D. Morel M.D. Maria C. Garzon M.D. 《Pediatric dermatology》2015,32(1):76-84
Capillary malformation–arteriovenous malformation syndrome (CM‐AVM) is an autosomal dominant disorder caused by RASA1 mutations. The prevalence and phenotypic spectrum are unknown. Evaluation of patients with multiple CMs is challenging because associated AVMs can be life threatening. The objective of this study was to describe the clinical characteristics of children presenting with features of CM‐AVM to an academic pediatric dermatology practice. After institutional review board approval was received, a retrospective chart review was performed of patients presenting between 2009 and 2012 with features of CM‐AVM. We report nine cases. Presenting symptoms ranged from extensive vascular stains and cardiac failure to CMs noted incidentally during routine skin examination. All demonstrated multiple CMs, two had Parkes Weber syndrome, and two had multiple infantile hemangiomas. Seven patients had family histories of multiple CMs; three had family histories of large, atypical CMs. Six had personal or family histories of AVMs. Genetic evaluation was recommended for all and was pursued by six families; four RASA1 mutations were identified, including one de novo. Consultations with neurology, cardiology, and orthopedics were recommended. Most patients (89%) have not required treatment to date. CM‐AVM is an underrecognized condition with a wide clinical spectrum that often presents in childhood. Further evaluation may be indicated in patients with multiple CMs. This study is limited by its small and retrospective nature. 相似文献
900.