全文获取类型
收费全文 | 3222541篇 |
免费 | 254978篇 |
国内免费 | 7549篇 |
专业分类
耳鼻咽喉 | 45468篇 |
儿科学 | 101499篇 |
妇产科学 | 86693篇 |
基础医学 | 460697篇 |
口腔科学 | 92475篇 |
临床医学 | 303044篇 |
内科学 | 621245篇 |
皮肤病学 | 64959篇 |
神经病学 | 271000篇 |
特种医学 | 125154篇 |
外国民族医学 | 1128篇 |
外科学 | 471937篇 |
综合类 | 76382篇 |
现状与发展 | 2篇 |
一般理论 | 1361篇 |
预防医学 | 269547篇 |
眼科学 | 74987篇 |
药学 | 240875篇 |
10篇 | |
中国医学 | 6506篇 |
肿瘤学 | 170099篇 |
出版年
2018年 | 34772篇 |
2017年 | 26570篇 |
2016年 | 29074篇 |
2015年 | 33108篇 |
2014年 | 47035篇 |
2013年 | 72384篇 |
2012年 | 98259篇 |
2011年 | 103940篇 |
2010年 | 60985篇 |
2009年 | 57634篇 |
2008年 | 97451篇 |
2007年 | 103595篇 |
2006年 | 104434篇 |
2005年 | 101429篇 |
2004年 | 97149篇 |
2003年 | 93426篇 |
2002年 | 91599篇 |
2001年 | 144608篇 |
2000年 | 149464篇 |
1999年 | 126442篇 |
1998年 | 37237篇 |
1997年 | 33786篇 |
1996年 | 33216篇 |
1995年 | 32102篇 |
1994年 | 30138篇 |
1993年 | 28215篇 |
1992年 | 102226篇 |
1991年 | 99306篇 |
1990年 | 96199篇 |
1989年 | 92258篇 |
1988年 | 85731篇 |
1987年 | 84298篇 |
1986年 | 80191篇 |
1985年 | 76631篇 |
1984年 | 58251篇 |
1983年 | 49714篇 |
1982年 | 30261篇 |
1981年 | 26934篇 |
1979年 | 54332篇 |
1978年 | 38435篇 |
1977年 | 32133篇 |
1976年 | 30613篇 |
1975年 | 32086篇 |
1974年 | 39423篇 |
1973年 | 37948篇 |
1972年 | 35356篇 |
1971年 | 32798篇 |
1970年 | 30681篇 |
1969年 | 28388篇 |
1968年 | 26267篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
41.
42.
43.
44.
45.
Platelets are needed to prevent or arrest bleeding and aggregate at the site of injury upon vascular damage. Platelets express receptors for estrogens which might affect the function of the platelets and their hemostatic ability. The aim was to identify possible differences in platelet function related to age, gender, and phases of the menstrual cycle by use of impedance aggregometry with Multiplate. In the first part of the study, platelet function was assessed in 60 healthy individuals (30 men and 30 women) in each of three age groups (20–25, 40–45, and 60–65 years). In the second part of the study, the platelet function was analyzed on four occasions during the menstrual cycle in women without oral contraceptives (OCs) (n = 17) and compared to 19 women on OCs and 18 men of similar age (20–40 years). For the women on OCs, aggregation was analyzed once during the tablet-free week and once late during the period with OCs. The men were sampled once. Women of younger age (<45 years) had significantly higher agonist-induced aggregation response than both men and post-menopausal women (60–65 years). The agonist-induced aggregation response did not differ between phases of the menstrual cycle or OC use. The results suggest that estradiol and/or progesterone affect spontaneous aggregation since it was found to be lowest in the mid-luteal phase. Spontaneous aggregation was significantly lower in women on OCs than in both men and women without OCs. Our findings indicate that fertile age is associated with higher aggregation response capacity of the platelets, possibly to prevent excessive bleeding during menstruation, but this response capacity is not altered during the menstrual cycle or by use of OCs. 相似文献
46.
47.
48.
49.
50.
Alexander E. J. Trevatt David R. Thomson Robert Miller Matthew Colquhoun Akinyemi I. Idowu Shakeel Rahman 《Journal of plastic surgery and hand surgery》2019,53(2):97-104
Academic output is just one aspect of a successful career as a plastic surgeon. However, for those with a strong interest in academia, the academic output of a department will likely be a key factor when deciding how to rank jobs. The aim of this study was to quantify and rank the academic output of plastic surgery units across the UK and Ireland. The Institute for Scientific Information (ISI) Web of Science Bibliometric analysis tool was used to collate cumulative (1950–2016), 10 year (2006–2016) and 3 years (2013–2015) research output data for plastic surgery units in the UK and Ireland. Sixty-six plastic surgery units were identified. Departments were ranked for each time period according to the number of papers produced, number of citations (Nc) and h-index (a measure of the impact of scientific output). The top 3 departments for number of papers in the last 10 years were The Royal Free Hospital, London (226) Broomfield Hospital, Chelmsford (218), and Morriston Hospital and Swansea (188). The top 3 for h-number were The Royal Free Hospital (21) Wythenshawe Hospital, Manchester (18) and Morriston Hospital (17). Academic output varies across plastic surgery units in the UK and Ireland. A number of departments have consistently maintained high academic outputs across the years and will be of interest to surgeons hoping to pursue a career in academia. 相似文献