全文获取类型
收费全文 | 2030篇 |
免费 | 148篇 |
国内免费 | 42篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 64篇 |
妇产科学 | 32篇 |
基础医学 | 266篇 |
口腔科学 | 25篇 |
临床医学 | 212篇 |
内科学 | 515篇 |
皮肤病学 | 46篇 |
神经病学 | 129篇 |
特种医学 | 236篇 |
外科学 | 165篇 |
综合类 | 18篇 |
预防医学 | 131篇 |
眼科学 | 9篇 |
药学 | 154篇 |
中国医学 | 1篇 |
肿瘤学 | 215篇 |
出版年
2023年 | 9篇 |
2022年 | 8篇 |
2021年 | 22篇 |
2020年 | 16篇 |
2019年 | 29篇 |
2018年 | 48篇 |
2017年 | 38篇 |
2016年 | 30篇 |
2015年 | 49篇 |
2014年 | 57篇 |
2013年 | 80篇 |
2012年 | 108篇 |
2011年 | 97篇 |
2010年 | 77篇 |
2009年 | 77篇 |
2008年 | 87篇 |
2007年 | 102篇 |
2006年 | 84篇 |
2005年 | 71篇 |
2004年 | 56篇 |
2003年 | 68篇 |
2002年 | 49篇 |
2001年 | 58篇 |
2000年 | 65篇 |
1999年 | 49篇 |
1998年 | 75篇 |
1997年 | 55篇 |
1996年 | 49篇 |
1995年 | 52篇 |
1994年 | 34篇 |
1993年 | 45篇 |
1992年 | 25篇 |
1991年 | 38篇 |
1990年 | 32篇 |
1989年 | 52篇 |
1988年 | 34篇 |
1987年 | 45篇 |
1986年 | 30篇 |
1985年 | 27篇 |
1984年 | 22篇 |
1983年 | 23篇 |
1982年 | 19篇 |
1981年 | 21篇 |
1980年 | 22篇 |
1979年 | 13篇 |
1978年 | 14篇 |
1977年 | 13篇 |
1976年 | 10篇 |
1975年 | 11篇 |
1972年 | 5篇 |
排序方式: 共有2220条查询结果,搜索用时 15 毫秒
1.
O Schouten J H H van Laanen E Boersma R Vidakovic H H H Feringa M Dunkelgrün J J Bax J Koning H van Urk D Poldermans 《European journal of vascular and endovascular surgery》2006,32(1):21-26
OBJECTIVE: To evaluate the effect of statins on aneurysm growth in a group of consecutive patients under surveillance for infrarenal aortic aneurysms (AAA). MATERIALS AND METHODS: All patients (59 statin users, 91 non-users) under surveillance between January 2002 and August 2005 with a follow-up for aneurysm growth of at least 12 months and a minimum of three diameter evaluations were retrospectively included in the analysis. Multiple regression analysis, weighted with the number of observations, was performed to test the influence of statins on AAA growth rate. RESULTS: During a median period of 3.1 (1.1-13.1) years the overall mean aneurysm growth rate was 2.95+/-2.8 mm/year. Statin users had a 1.16 mm/year lower AAA growth rate compared to non-users (95% CI 0.33-1.99 mm/year). Increased age was associated with a slower growth (-0.09 mm/year per year, p = 0.003). Female gender (+1.82 mm/year, p = 0.008) and aneurysm diameter (+0.06 mm/year per mm, p = 0.049) were associated with increased AAA growth. The use of non-steroidal anti-inflammatory drugs, chronic lung disease, or other cardiovascular risk factors were not independently associated with AAA growth. CONCLUSIONS: Statins appear to be associated with attenuation of AAA growth, irrespective of other known factors influencing aneurysm growth. 相似文献
2.
3.
Accuracy of an anthropometric estimate of the muscle and bone area in a transversal cross-section of the arm 总被引:3,自引:0,他引:3
F L de Koning R A Binkhorst J M Kauer H O Thijssen 《International journal of sports medicine》1986,7(5):246-249
To standardize the maximal static force (Fo) of the arm flexors, the accuracy of an anthropometric method for estimating the mid-arm cross-sectional muscle and bone area (MBA) was investigated. This was done by comparing the anthropometrically determined area (MBA.A) with the area measured by means of computerized tomography (MBA.S). In the same way, the accuracy of Heymsfield's equations (Heymsfield et al., 1982) for predicting MBA (MBA.H) from anthropometric measures was tested. MBA.A was significantly larger than MBA.S, the relative difference increasing with the thickness of the subcutaneous fat layer. This difference was attributed to a 27% underestimation of the fat layer thickness as measured with the skinfold caliper. Women being fatter than men, this caused the standardized maximal static force (Fo/MBA) to be lower in women than in men. MBA.H was 12% smaller than MBA.S. This may have been due to a difference in the way of measuring the arm circumference between the present authors and Heymsfield et al. 相似文献
4.
A patient known with acute intermittent porphyria who developed primary liver-cell carcinoma is described. No other risk factors were found. A possible association of acute intermittent porphyria with the development of primary liver-cell carcinoma has been suggested in recent, mainly Scandinavian literature. So far this association has never been described in The Netherlands. 相似文献
5.
6.
7.
8.
9.
10.
The effects of co-culture with human fibroblasts on human embryo development in vitro and implantation 总被引:5,自引:0,他引:5
Wetzels AM; Bastiaans BA; Hendriks JC; Goverde HJ; Punt-van der Zalm AP; Verbeet JG; Braat DD 《Human reproduction (Oxford, England)》1998,13(5):1325-1330
In a human in-vitro fertilization (IVF) programme, the effect of co-
culture of embryos with human fibroblasts was evaluated with respect to
pregnancy rate and embryo development. Patients were included in the study
after giving informed written consent. The IVF treatments were randomly
assigned by stratification of both age (<36 versus > or =36 years)
and previous IVF attempts (yes versus no). After fertilization was
established, the zygotes were transferred to a 4-well dish with or without
fibroblasts and cultured for 2 days. On the third day after ovum pick-up
(OPU), cell number and quality [5 (good) to 1 (poor)] of the embryos were
scored and a maximum of three embryos was transferred. Supernumerary
embryos of good quality were cryopreserved. The design of this study was a
group sequential trial with the objective of detecting differences between
pregnancy rates following IVF with conventional incubation or incubation in
co-culture with fibroblasts. This design included one evaluation at
half-way data collection. In the study, 148 patients had an OPU, of whom 77
were allocated to the co-culture group. There was no statistically
significant difference in pregnancy rate, cell number and embryo quality
between the two groups. The ongoing pregnancy rate per embryo transfer was
27% in co-culture and 30% in the conventional culture group. The
implantation rates per transferred embryo were 17 and 18% respectively.
Using a multivariate logistic regression model for the probability of
ongoing pregnancies, the odds ratio of co-culture, adjusted for age and
previous IVF attempts, was not statistically significant. In conclusion,
co-culture with human fibroblasts does not contribute to an improvement of
embryo quality nor to a higher pregnancy rate after IVF in an unselected
group of patients.
相似文献