全文获取类型
收费全文 | 311232篇 |
免费 | 279296篇 |
国内免费 | 39773篇 |
专业分类
耳鼻咽喉 | 2739篇 |
儿科学 | 5380篇 |
妇产科学 | 3199篇 |
基础医学 | 92924篇 |
口腔科学 | 4336篇 |
临床医学 | 65747篇 |
内科学 | 102103篇 |
皮肤病学 | 5108篇 |
神经病学 | 23609篇 |
特种医学 | 11980篇 |
外科学 | 45151篇 |
综合类 | 65963篇 |
一般理论 | 11篇 |
预防医学 | 49757篇 |
眼科学 | 20117篇 |
药学 | 63397篇 |
5篇 | |
中国医学 | 51593篇 |
肿瘤学 | 17182篇 |
出版年
2020年 | 6180篇 |
2019年 | 13406篇 |
2018年 | 14002篇 |
2017年 | 14662篇 |
2016年 | 13298篇 |
2015年 | 13181篇 |
2014年 | 13105篇 |
2013年 | 13349篇 |
2012年 | 13649篇 |
2011年 | 19542篇 |
2010年 | 19900篇 |
2009年 | 26551篇 |
2008年 | 14124篇 |
2007年 | 10324篇 |
2006年 | 9997篇 |
2005年 | 11006篇 |
2004年 | 17878篇 |
2003年 | 16431篇 |
2002年 | 15154篇 |
2001年 | 15675篇 |
2000年 | 9658篇 |
1999年 | 15207篇 |
1998年 | 15736篇 |
1997年 | 15423篇 |
1996年 | 15838篇 |
1995年 | 15955篇 |
1994年 | 15664篇 |
1993年 | 14970篇 |
1992年 | 14115篇 |
1991年 | 13309篇 |
1990年 | 12051篇 |
1989年 | 11742篇 |
1988年 | 11138篇 |
1987年 | 10446篇 |
1986年 | 9949篇 |
1985年 | 8766篇 |
1984年 | 6757篇 |
1983年 | 6699篇 |
1982年 | 7710篇 |
1981年 | 7241篇 |
1980年 | 6884篇 |
1979年 | 6784篇 |
1978年 | 5921篇 |
1977年 | 6221篇 |
1976年 | 5840篇 |
1975年 | 5582篇 |
1974年 | 5129篇 |
1973年 | 4837篇 |
1972年 | 4815篇 |
1971年 | 4155篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
11.
Abstract It is well established that thrombolytic therapy increases the risk of secondary intracerebral hemorrhage in ischemic stroke
patients. However, the term “intracerebral hemorrhage” (ICH) covers a wide spectrum from tiny spots of blood to massive space-occupying
hematoma. We will review the etiology and clinical consequences of secondary hemorrhage after thrombolysis in ischemic stroke
patients and discuss the ability of magnetic resonance imaging (MRI) to predict this phenomenon. MRI is a highly sensitive
tool for detection of hemorrhagic transformation after ischemic stroke. The definitions of a so-called symptomatic hemorrhage
after ischemic infarction differ considerably and will also be described. Attributing a causal relationship of a clinical
deterioration to a secondary hemorrhage is not easy and should be only addressed when it exceeds at least 30% of the infarct
volume. In other patients, secondary hemorrhage might be regarded as side effect of reperfusion within the region with the
most severe perfusion deficit. Cerebral microbleeds (CMBs) are a frequent finding in patients with leukoaraiosis and appear
to be a general marker of various types of bleeding- prone small vessel disease and a predictor of recurrent vascular events.
Current data do not support the hypothesis that the detection of CMBs is a useful diagnostic criterion for the exclusion of
patients with CMBs from thrombolytic therapy. However, an increased risk for the rare patients with numerous CMBs can not
be ruled out.
相似文献
12.
Access to good-quality health services is crucial for the improvement of many health outcomes, such as those targeted by the
Millennium Development Goals (MDGs) adopted by the international community in 2000. The health-related MDGs cannot be achieved
if vulnerable populations do not have access to skilled personnel and to other necessary inputs. This paper focuses on the
geographical dimension of access and on one of its critical determinants: the availability of qualified personnel. The objective
of this paper is to offer a better understanding of the determinants of geographical imbalances in the distribution of health
personnel, and to identify and assess the strategies developed to correct them. It reviews the recent literature on determinants,
barriers and the effects of strategies that attempted to correct geographical imbalances, with a focus on empirical studies
from developing and developed countries. An analysis of determinants of success and failures of strategies implemented, and
a summary of lessons learnt, is included. 相似文献
13.
14.
15.
Jean-Sébastien Fallu Jürgen Rehm Emmanuel N. Kuntsche Esther Grichting Neerav Monga Edward M. Adlaf Susan J Bondy Gerhard Gmel 《Sozial- und Pr?ventivmedizin》2006,8(1):363-372
Volume and profile of alcohol consumption among students and classmates as predictors of aggression and victimization: a multilevel
analysis among Swiss adolescents
Objective:
To test the effects of the volume of alcohol consumption and drinking patterns on alcohol-related aggression and victimization, both at the individual and class levels. 相似文献16.
17.
Tetsuro Sano Munetaka Masuda Shigeki Morita Hisataka Yasui 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2006,54(4):149-154
OBJECTIVE: It is well documented that cardiopulmonary bypass (CPB) severely impairs cellular immunity. The objective of this study was to investigate the effect of prostaglandin E1 (PGE1) on cellular immunity after CPB. METHODS: Patients who underwent elective cardiac surgery were randomly divided into the PGE1 group (n=12) and the control group (n=12). In the PGE1 group, PGE1 was administered at 20 ng/kg/min from just after the induction of anesthesia to the end of surgery. Peripheral blood mononuclear cells (PBMCs) were taken before anesthesia and on postoperative days 1, 3 and 7 (POD 1, POD 3 and POD 7). Proliferation responses of T cells to phytohemagglutinin (PHA) and pure protein derivative (PPD) antigen were measured as indicators of cellular immunity. RESULTS: PGE1 significantly attenuated the impairment of both PHA and PPD response after cardiac surgery on POD 1 (PHA response, 30 +/- 21% vs. 53 +/- 32%, control vs. PGE, p=0.048; PPD response, 18 +/- 21% vs. 39 +/- 27%, control vs. PGE, p=0.046). The reduced glutathione content of PBMCs in the control group was significantly decreased on POD 1. CONCLUSION: PGE1 attenuated the impairment of cellular immunity after cardiac surgery with CPB by reducing oxidative stress on PBMCs. 相似文献
18.
19.
20.