全文获取类型
收费全文 | 1962篇 |
免费 | 311篇 |
国内免费 | 41篇 |
专业分类
耳鼻咽喉 | 14篇 |
儿科学 | 108篇 |
妇产科学 | 20篇 |
基础医学 | 97篇 |
口腔科学 | 26篇 |
临床医学 | 346篇 |
内科学 | 610篇 |
皮肤病学 | 62篇 |
神经病学 | 172篇 |
特种医学 | 280篇 |
外科学 | 320篇 |
综合类 | 34篇 |
预防医学 | 62篇 |
眼科学 | 16篇 |
药学 | 88篇 |
中国医学 | 1篇 |
肿瘤学 | 58篇 |
出版年
2024年 | 9篇 |
2023年 | 52篇 |
2022年 | 15篇 |
2021年 | 34篇 |
2020年 | 92篇 |
2019年 | 16篇 |
2018年 | 93篇 |
2017年 | 75篇 |
2016年 | 74篇 |
2015年 | 64篇 |
2014年 | 97篇 |
2013年 | 115篇 |
2012年 | 58篇 |
2011年 | 47篇 |
2010年 | 86篇 |
2009年 | 114篇 |
2008年 | 53篇 |
2007年 | 49篇 |
2006年 | 52篇 |
2005年 | 37篇 |
2004年 | 24篇 |
2003年 | 26篇 |
2002年 | 25篇 |
2001年 | 35篇 |
2000年 | 28篇 |
1999年 | 36篇 |
1998年 | 82篇 |
1997年 | 100篇 |
1996年 | 78篇 |
1995年 | 70篇 |
1994年 | 50篇 |
1993年 | 52篇 |
1992年 | 33篇 |
1991年 | 19篇 |
1990年 | 31篇 |
1989年 | 57篇 |
1988年 | 57篇 |
1987年 | 40篇 |
1986年 | 29篇 |
1985年 | 28篇 |
1984年 | 17篇 |
1983年 | 11篇 |
1982年 | 15篇 |
1981年 | 16篇 |
1980年 | 16篇 |
1979年 | 12篇 |
1978年 | 11篇 |
1977年 | 9篇 |
1976年 | 11篇 |
1971年 | 11篇 |
排序方式: 共有2314条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
5.
6.
7.
8.
筛检对肝癌死亡率影响的研究 总被引:5,自引:0,他引:5
5581名HBsAg阳性的男性随机分入周期性筛检组(A组,3712人)及对照组(B组,1869人)。A组(19155.4人年)共发生肝癌257例,B组(9785.5人年)为117例,两组的肝癌发生率分别为1342/10万与1196/10万;两组肝癌死亡分别为218与109例,肝癌死亡率分别为1138/10万与1114/10万。两组中Ⅰ期肝癌病例分别为29.6%与6.0%,差异有非常显著性意义。1、3、5年相对生存率A组为23.7%、7.0%、4.0%,B组为9.7%、4.0%、4.1%。用Poisson回归模型拟合显示,在调正年龄、初筛AFP及入列年份后,筛检对于肝癌的相对危险度为0.83,95%CI为0.68~1.03,有较弱的“保护”作用,Cox回归模型拟合结果显示当临床分期未引入模型时,筛检对于肝癌有显著的“保护”作用:危险率为0.6617,95%CI为0.5234~0.8365;而模型经调整后,危险率即接近“1”,95%CI为0.74~1.26。 相似文献
9.
Ralls PW; Johnson MB; Kanel G; Dobalian DM; Colletti PM; Boswell WD Jr; Radin DR; Halls JM 《Radiology》1986,161(2):451-454
FM sonography - a signal-processing technique that uses frequency and phase information as well as amplitude data - shows promise in evaluation of patients with diffuse liver disease. In a prospective blinded review of 37 patients with biopsy-proved liver disease and 42 healthy volunteers, FM sonography was clearly superior to traditional amplitude-based (AM) sonography in distinguishing healthy from diseased subjects. Statistically significant differences were seen in accuracy (FM, 98.7%; AM, 84.8%), sensitivity (FM, 97.3%; AM, 70.3%), and negative predictive value (FM, 97.7%; AM, 78.8%). Our data also suggest that current FM sonographic techniques cannot differentiate among histologic findings associated with different hepatic parenchymal abnormalities. It is unclear, therefore, whether FM imaging can reduce the numbers of patients who require biopsy for diagnosis or the frequency of biopsy procedures in patients with known disease. 相似文献
10.
Artificial dermis for major burns. A multi-center randomized clinical trial. 总被引:12,自引:0,他引:12 下载免费PDF全文
D Heimbach A Luterman J Burke A Cram D Herndon J Hunt M Jordan W McManus L Solem G Warden et al. 《Annals of surgery》1988,208(3):313-320
This communication presents an 11-center prospective randomized trial using the artificial dermis invented by Burke and Yannas. Patients with life-threatening burns who underwent primary excision and grafting within 7 days of injury had comparable sites randomized to receive either the artificial dermis (study site) or the investigator's usual skin grafting material (control site). Control materials were autograft, allograft, xenograft, or a synthetic dressing. Epidermal grafts were applied to the study site during a second operation, and surviving patients were followed for 1 year after grafting. One hundred thirty-nine sites on 106 patients were studied. Mean burn size was 46.5 +/- 15% mean total body surface (TBSA). Overall mortality was 13%, and mean hospital stay was 68 +/- 45 days. Median artificial dermis take was 80% compared with 95% for all comparative sites, but the take was equivalent to that of all nonautograft control materials. Results with the artificial dermis improved slightly as the investigators became more familiar with the material. Donor site thickness for the study site averaged .006' +/- .002' compared to .013' +/- .018' for control (p less than .0001) and the epidermal donor site healed an average of 4 days sooner (10 +/- 6 vs. 14 +/- 8 days) (p less than .0001). As the wounds matured during the first year, both patients and surgeons felt that both sites became more comparable in appearance and function. At the completion of the study, there was less hypertrophic scarring of the artificial dermis, and more patients preferred the artificial dermis to the control graft. Artificial dermis with an epidermal graft provides a permanent cover that is at least as satisfactory as currently available skin grafting techniques, and uses donor grafts that are thinner and donor sites that heal faster. 相似文献