全文获取类型
收费全文 | 176篇 |
免费 | 9篇 |
国内免费 | 10篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 17篇 |
妇产科学 | 3篇 |
基础医学 | 19篇 |
口腔科学 | 4篇 |
临床医学 | 24篇 |
内科学 | 35篇 |
皮肤病学 | 2篇 |
神经病学 | 1篇 |
特种医学 | 32篇 |
外科学 | 5篇 |
综合类 | 5篇 |
预防医学 | 16篇 |
眼科学 | 1篇 |
药学 | 16篇 |
中国医学 | 1篇 |
肿瘤学 | 12篇 |
出版年
2021年 | 1篇 |
2019年 | 2篇 |
2018年 | 2篇 |
2017年 | 2篇 |
2016年 | 3篇 |
2014年 | 1篇 |
2013年 | 6篇 |
2012年 | 3篇 |
2011年 | 2篇 |
2010年 | 5篇 |
2009年 | 9篇 |
2008年 | 4篇 |
2007年 | 9篇 |
2006年 | 4篇 |
2005年 | 6篇 |
2004年 | 6篇 |
2003年 | 3篇 |
2002年 | 9篇 |
2001年 | 5篇 |
2000年 | 12篇 |
1999年 | 5篇 |
1998年 | 12篇 |
1997年 | 8篇 |
1996年 | 6篇 |
1995年 | 6篇 |
1994年 | 10篇 |
1993年 | 11篇 |
1992年 | 6篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 7篇 |
1988年 | 2篇 |
1987年 | 3篇 |
1986年 | 4篇 |
1985年 | 1篇 |
1984年 | 2篇 |
1983年 | 2篇 |
1980年 | 3篇 |
1979年 | 1篇 |
1977年 | 1篇 |
1976年 | 5篇 |
1975年 | 2篇 |
1875年 | 1篇 |
排序方式: 共有195条查询结果,搜索用时 15 毫秒
131.
132.
133.
Successful percutaneous replacement of the venous limb of a LeVeen peritoneovenous shunt with the use of angioplastic technique is reported. This method may be a first line of treatment in patients with intractable ascites and a failing shunt caused by chronic occlusion of the superior vena cava. 相似文献
134.
135.
136.
137.
AO Laiyemo G Murphy LB Sansbury Z Wang PS Albert PM Marcus RE Schoen AJ Cross A Schatzkin E Lanza 《Clinical gastroenterology and hepatology》2009,7(2):192-197
BACKGROUND AND AIMS: Recent studies have suggested that some hyperplastic polyps may be associated with an increased risk of colorectal cancer. Prospective information on the risk of adenoma recurrence associated with hyperplastic polyps is limited. We sought to investigate whether the coexistence of hyperplastic polyps with adenomas increases the risk of adenoma recurrence. METHODS: We used unconditional logistic regression models to examine the association between baseline hyperplastic polyps and subsequent adenoma recurrence during a 3-year follow-up evaluation, among 1637 participants in the Polyp Prevention Trial. RESULTS: A total of 437 participants (26.7%) had hyperplastic polyps coexisting with adenomas at baseline. Of these, 132 (30.2%) had at least one hyperplastic polyp in the proximal colon, whereas 305 (69.8%) had only distal hyperplastic polyps. When compared with subjects without any hyperplastic polyps at baseline, there was no statistically significant association between the presence of baseline hyperplastic polyps and recurrence of any adenoma (odds ratio [OR], 1.19; 95% confidence interval [CI], 0.94-1.51) or advanced adenoma (OR, 1.25; 95% CI, 0.78-2.03). Also, there was no association between hyperplastic polyp location and adenoma recurrence (OR, 1.01; 95% CI, 0.69-1.48) for any proximal hyperplastic polyp (OR, 1.26; 95% CI, 0.96-1.65) and for distal hyperplastic polyps. CONCLUSIONS: The coexistence of hyperplastic polyps with adenomas, irrespective of location, does not confer an increased risk of adenoma recurrence beyond that of adenomas alone within 3 years of follow-up evaluation. Prospective long-term studies on adenoma recurrence risk associated with hyperplastic polyps in screening populations are needed. 相似文献
138.
L Aires LB Andersen D Mendonça C Martins G Silva J Mota 《Acta paediatrica (Oslo, Norway : 1992)》2010,99(1):140-144
Aim: To analyse whether changes in physical activity index (PAI), screen time (ST: television, computer) and body mass index (BMI) made a contribution to longitudinal changes in fitness of children and adolescents. Additionally, we analysed the interaction between baseline fitness level and changes in fitness.
Methods: This is a 3-year longitudinal study of 345 high school students aged 11–19 years. Students performed curl-ups, push-ups and 20-m shuttle run tests from Fitnessgram. PA and ST were evaluated using a standard questionnaire. Standardized scores of fitness tests were summed. Changes over time were calculated as Δ1 (2007 minus 2006), Δ2 (2008 minus 2007) and Δ3 (2008 minus 2006).
Results: Changes in PAI were positively and independently associated with changes in fitness in Δ1 , Δ2 and Δ3 . Changes in BMI were negatively associated with changes in fitness in Δ3 . Participants highly fit at baseline were those who showed positive changes in PAI over Δ3 , decreased changes in ST and had the lowest increase in BMI over 3 years compared with those low-fit at baseline.
Conclusions: Changes in BMI were associated with changes in fitness over 3 years. However, changes in PAI were the best predictor for changes in fitness in each year and over the 3 years of evaluation in youth. 相似文献
Methods: This is a 3-year longitudinal study of 345 high school students aged 11–19 years. Students performed curl-ups, push-ups and 20-m shuttle run tests from Fitnessgram. PA and ST were evaluated using a standard questionnaire. Standardized scores of fitness tests were summed. Changes over time were calculated as Δ
Results: Changes in PAI were positively and independently associated with changes in fitness in Δ
Conclusions: Changes in BMI were associated with changes in fitness over 3 years. However, changes in PAI were the best predictor for changes in fitness in each year and over the 3 years of evaluation in youth. 相似文献
139.
140.
Ciria HC Quevedo MS Cabrales LB Bruzón RP Salas MF Pena OG González TR López DS Flores JM 《BMC cancer》2004,4(1):1-10