全文获取类型
收费全文 | 2791篇 |
免费 | 237篇 |
国内免费 | 2篇 |
专业分类
耳鼻咽喉 | 41篇 |
儿科学 | 66篇 |
妇产科学 | 82篇 |
基础医学 | 304篇 |
口腔科学 | 73篇 |
临床医学 | 396篇 |
内科学 | 545篇 |
皮肤病学 | 26篇 |
神经病学 | 224篇 |
特种医学 | 144篇 |
外科学 | 363篇 |
综合类 | 83篇 |
一般理论 | 1篇 |
预防医学 | 247篇 |
眼科学 | 64篇 |
药学 | 216篇 |
中国医学 | 10篇 |
肿瘤学 | 145篇 |
出版年
2022年 | 21篇 |
2021年 | 49篇 |
2020年 | 23篇 |
2019年 | 42篇 |
2018年 | 63篇 |
2017年 | 41篇 |
2016年 | 42篇 |
2015年 | 55篇 |
2014年 | 76篇 |
2013年 | 119篇 |
2012年 | 141篇 |
2011年 | 157篇 |
2010年 | 87篇 |
2009年 | 86篇 |
2008年 | 154篇 |
2007年 | 147篇 |
2006年 | 135篇 |
2005年 | 155篇 |
2004年 | 136篇 |
2003年 | 139篇 |
2002年 | 122篇 |
2001年 | 54篇 |
2000年 | 53篇 |
1999年 | 45篇 |
1998年 | 28篇 |
1997年 | 22篇 |
1996年 | 22篇 |
1995年 | 32篇 |
1992年 | 49篇 |
1991年 | 44篇 |
1990年 | 49篇 |
1989年 | 48篇 |
1988年 | 33篇 |
1987年 | 40篇 |
1986年 | 29篇 |
1985年 | 35篇 |
1984年 | 43篇 |
1983年 | 15篇 |
1982年 | 24篇 |
1981年 | 17篇 |
1980年 | 15篇 |
1979年 | 22篇 |
1978年 | 22篇 |
1977年 | 16篇 |
1976年 | 15篇 |
1974年 | 21篇 |
1973年 | 16篇 |
1972年 | 17篇 |
1971年 | 16篇 |
1970年 | 20篇 |
排序方式: 共有3030条查询结果,搜索用时 0 毫秒
1.
2.
We thank Coceani and L'Abbate for their comments on our paper.We concur that pathophysiology cannot be inferred fromcoronary lumenography alone, and this was one of thekey motivations in conducting the present study. 相似文献
3.
A systematic review of the ultrasound estimation of fetal weight. 总被引:10,自引:0,他引:10
N J Dudley 《Ultrasound in obstetrics & gynecology》2005,25(1):80-89
OBJECTIVES: The range and use of ultrasound fetal measurements have gradually been extended. Measurements have been combined to estimate fetal weight by mathematically based non-linear regression analysis or physically based volumetric methods. Fetal weight estimation is inaccurate, with poor sensitivity for prediction of fetal compromise. Several authors have shown the unacceptable level of intra- and interobserver variability in fetal measurement and the impact of errors on growth assessment. The aims of this study were to review the available methods and possible sources of inaccuracy. METHODS: Four databases were searched for studies comparing ultrasound estimated fetal weight (EFW) with birth weight. Studies meeting the inclusion criteria evaluated 11 different methods. Errors were graphically summarized. RESULTS: No consistently superior method has emerged. Volumetric methods provide some theoretical advantages. Random errors are large and must be reduced if clinical errors are to be avoided. CONCLUSIONS: The accuracy of EFW is compromised by large intra- and interobserver variability. Efforts must be made to minimize this variability if EFW is to be clinically useful. This may be achieved through averaging of multiple measurements, improvements in image quality, uniform calibration of equipment, careful design and refinement of measurement methods, acknowledgment that there is a long learning curve, and regular audit of measurement quality. Further work to improve the universal validity and accuracy of fetal weight estimation formulae is also required. 相似文献
4.
5.
Oestrogens and the lower urinary tract 总被引:1,自引:0,他引:1
6.
7.
Beth Hoskins Dudley F. Peeler Kathia Lawson Angie M. Barnes Ing K. Ho 《Brain research bulletin》1991,27(2):279-281
The effects of haloperidol on motor and functioning and cognitive functioning were studied in young (3-5 months old) and aged (20-22 months old) male mice by examining haloperidol-induced catalepsy and haloperidol-induced decrements in performance on a radial arm maze. The aged mice were much more sensitive to these adverse effects of haloperidol than were the young mice. Studies of the distribution of radioactivity from [3H]haloperidol to the brain indicated that the differences in sensitivity to this drug were not due to pharmacokinetic differences. The results demonstrate that mice are suitable for studies of aging-induced changes in the behavioral effects of neuroleptic agents. 相似文献
8.
T Shimizu D K Dudley P Borodchack J Belcher S L Perkins W Gibb 《Gynecologic and obstetric investigation》1992,34(3):142-145
Fibronectin production from amnion and placental tissues was evaluated in pregnant woman smokers and nonsmokers in order to examine if there were alterations of fibronectin metabolism in intrauterine tissues. In both amnion and placental tissues, cycloheximide inhibited the fibronectin output indicating that it was being synthesized. Mean fibronectin output by amnion in pregnant woman smokers was significantly lower than that in pregnant woman nonsmokers. In contrast, in the placenta from pregnant woman smokers, the output was significantly higher than that in pregnant woman nonsmokers. The present observations indicate that smoking alters an important biochemical constituent in amnion and placenta, possible leading to some complications. 相似文献
9.
10.