全文获取类型
收费全文 | 992篇 |
免费 | 58篇 |
国内免费 | 3篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 79篇 |
妇产科学 | 13篇 |
基础医学 | 70篇 |
口腔科学 | 13篇 |
临床医学 | 39篇 |
内科学 | 118篇 |
皮肤病学 | 5篇 |
神经病学 | 37篇 |
特种医学 | 47篇 |
外科学 | 40篇 |
综合类 | 54篇 |
预防医学 | 213篇 |
眼科学 | 3篇 |
药学 | 12篇 |
中国医学 | 1篇 |
肿瘤学 | 308篇 |
出版年
2022年 | 2篇 |
2021年 | 7篇 |
2020年 | 6篇 |
2019年 | 9篇 |
2018年 | 17篇 |
2017年 | 8篇 |
2016年 | 11篇 |
2015年 | 22篇 |
2014年 | 18篇 |
2013年 | 29篇 |
2012年 | 26篇 |
2011年 | 36篇 |
2010年 | 20篇 |
2009年 | 14篇 |
2008年 | 40篇 |
2007年 | 40篇 |
2006年 | 51篇 |
2005年 | 57篇 |
2004年 | 72篇 |
2003年 | 39篇 |
2002年 | 55篇 |
2001年 | 45篇 |
2000年 | 54篇 |
1999年 | 69篇 |
1998年 | 19篇 |
1997年 | 24篇 |
1996年 | 23篇 |
1995年 | 22篇 |
1994年 | 12篇 |
1993年 | 13篇 |
1992年 | 24篇 |
1991年 | 19篇 |
1990年 | 26篇 |
1989年 | 23篇 |
1988年 | 18篇 |
1987年 | 18篇 |
1986年 | 10篇 |
1985年 | 7篇 |
1984年 | 7篇 |
1983年 | 5篇 |
1982年 | 5篇 |
1981年 | 8篇 |
1980年 | 5篇 |
1979年 | 5篇 |
1978年 | 2篇 |
1977年 | 3篇 |
1976年 | 3篇 |
1975年 | 2篇 |
1970年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有1053条查询结果,搜索用时 15 毫秒
1.
2.
Christine E. East Fung Yee Chan Shaun P. Brennecke James F. King Paul B. Colditz 《分娩》2006,33(2):101-109
Abstract: Background: Fetal pulse oximetry improves the assessment of fetal well‐being during labor. The objective of this study was to evaluate women's satisfaction with their experience with this additional technology. Methods: We surveyed women participating in the FOREMOST trial, a randomized controlled trial comparing the addition of fetal pulse oximetry (FPO) to conventional cardiotocograph (CTG) monitoring (intervention group), versus CTG‐only (control group), in the presence of nonreassuring fetal status during labor. Our survey evaluated 3 aspects of women's experience: labor, fetal monitoring, and participation in the research. The survey was administered within a few days of giving birth and repeated 3 months later. Results: No differences were found between the intervention and control groups for women's evaluations of their labor, fetal monitoring, research, or overall experiences when surveyed on both occasions. Within each study group, a small but statistically significant decline occurred in women's scores for their experience of labor and overall experience from the initial survey close to the time of giving birth, to 3 months later. The magnitude of differences in responses over time was similar for the both groups. Women were more satisfied after a spontaneous or assisted vaginal birth than after cesarean section. Length of time the research midwife was present had a significant positive effect on women's ratings of their experience several days after giving birth (p = 0.006), but no effect at 3 months. Conclusions: The addition of fetal pulse oximetry for the assessment of fetal well‐being during labor did not affect childbearing women's perceptions of fetal monitoring or their labor. Women evaluated their experience in the research process positively overall. Small changes occurred in women's perception of their satisfaction over time. (BIRTH 33:2 June 2006) 相似文献
3.
4.
5.
6.
Inhibition of PAF-induced eosinophil accumulation in pulmonary airways of guinea pigs by anti-asthma drugs 总被引:3,自引:0,他引:3
S Sanjar S Aoki K Boubekeur L Burrows I Colditz I Chapman J Morley 《Japanese journal of pharmacology》1989,51(2):167-172
Intraperitoneal (i.p.) injection of platelet activating factor (PAF) in guinea pigs caused a dose-related increase in the number of eosinophils recovered from bronchoalveolar lavage fluid (BALF). The prevalence of eosinophils in BALF had significantly increased within 1 hr of i.p. injection of PAF (10 micrograms/animal) and was maximal after 24 hr. Subcutaneous osmotic mini-pumps were used to administer drugs for 5 days prior to i.p. injection of PAF (10 micrograms/animal) and for the subsequent 24 hr. The percentage increase of eosinophils in BALF, due to PAF, was inhibited in animals treated with dexamethasone, aminophylline, cromoglycate, tranilast or ketotifen, but not in animals treated with oxatomide, azelastine, amlexanox, ibudilast or AA-861. These results suggest that inhibition of pulmonary eosinophilia may be a necessary property of prophylactic anti-asthma drugs and provide indirect evidence favoring a role for PAF in eosinophilia of asthma. 相似文献
7.
Heather J Baer Graham A Colditz Walter C Willett Joanne F Dorgan 《Cancer epidemiology, biomarkers & prevention》2007,16(9):1880-1888
Greater body fatness during childhood is associated with reduced risk of premenopausal breast cancer, but few studies have addressed the relation of adiposity with sex hormones in girls. We prospectively examined associations between adiposity and circulating levels of sex hormones and sex hormone-binding globulin (SHBG) among 286 girls in the Dietary Intervention Study in Children. Participants were 8 to 10 years old at baseline and were followed for an average of 7 years. Anthropometric measurements were taken at baseline and at subsequent annual visits, and blood samples were collected every 2 years. Concentrations of dehydroepiandrosterone sulfate (DHEAS) during follow-up were higher among girls with greater body mass index (BMI) at baseline. The mean for the lowest BMI quartile was 63.0 microg/dL compared with 78.8 microg/dL for the highest quartile, and each kg/m(2) increment in baseline BMI was associated with a 4.3% increase (95% confidence interval, 1.6-7.0%) in DHEAS levels during follow-up (P(trend) = 0.002). Concentrations of SHBG during follow-up were lower among girls with greater BMI at baseline. The mean for the lowest BMI quartile was 94.8 nmol compared with 57.5 nmol for the highest quartile, and each kg/m(2) increment in baseline BMI was associated with an 8.8% decrease (95% confidence interval, 7.0-10.6%) in SHBG levels during follow-up (P(trend) < 0.0001). Estrogen and progesterone concentrations were similar across BMI quartiles. These findings suggest that adiposity may alter DHEAS and SHBG levels in girls. Whether and how these differences affect breast development and carcinogenesis requires further research. 相似文献
8.
9.
10.
We examined relative weight and height in relation to subsequent breast cancer risk among 115,534 women 30 to 55 years of age and free from cancer in 1976. By 1984, six hundred fifty-eight premenopausal and 420 postmenopausal breast cancers were documented during 734,716 person-years. Among premenopausal women, risk of breast cancer decreased significantly with increasing relative weight (relative risk for the highest category was 0.6). A similar inverse association was seen for recalled relative weight at 18 years of age. Postmenopausal breast cancer was not associated with relative weight, either recent or at age 18. Height was not associated with breast cancer risk among premenopausal women and only weakly related among postmenopausal women. These data suggest that obesity among premenopausal and early postmenopausal women does not increase breast cancer risk substantially. 相似文献