全文获取类型
收费全文 | 1297篇 |
免费 | 104篇 |
国内免费 | 15篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 55篇 |
妇产科学 | 21篇 |
基础医学 | 157篇 |
口腔科学 | 56篇 |
临床医学 | 160篇 |
内科学 | 229篇 |
皮肤病学 | 7篇 |
神经病学 | 64篇 |
特种医学 | 154篇 |
外科学 | 181篇 |
综合类 | 52篇 |
预防医学 | 97篇 |
眼科学 | 7篇 |
药学 | 110篇 |
肿瘤学 | 65篇 |
出版年
2021年 | 19篇 |
2020年 | 15篇 |
2019年 | 16篇 |
2018年 | 26篇 |
2017年 | 10篇 |
2016年 | 13篇 |
2015年 | 14篇 |
2014年 | 18篇 |
2013年 | 37篇 |
2012年 | 31篇 |
2011年 | 36篇 |
2010年 | 37篇 |
2009年 | 51篇 |
2008年 | 48篇 |
2007年 | 38篇 |
2006年 | 49篇 |
2005年 | 44篇 |
2004年 | 28篇 |
2003年 | 41篇 |
2002年 | 31篇 |
2001年 | 28篇 |
2000年 | 32篇 |
1999年 | 36篇 |
1998年 | 35篇 |
1997年 | 44篇 |
1996年 | 51篇 |
1995年 | 27篇 |
1994年 | 29篇 |
1993年 | 33篇 |
1992年 | 27篇 |
1991年 | 31篇 |
1990年 | 28篇 |
1989年 | 38篇 |
1988年 | 48篇 |
1987年 | 33篇 |
1986年 | 38篇 |
1985年 | 29篇 |
1984年 | 15篇 |
1983年 | 13篇 |
1982年 | 18篇 |
1981年 | 12篇 |
1980年 | 18篇 |
1979年 | 20篇 |
1978年 | 14篇 |
1977年 | 12篇 |
1976年 | 17篇 |
1975年 | 12篇 |
1973年 | 7篇 |
1972年 | 9篇 |
1969年 | 7篇 |
排序方式: 共有1416条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
5.
6.
7.
8.
Emergency airway management in patients with cervical spine injuries 总被引:10,自引:0,他引:10
9.
G R Parr D E Steflik A L Sisk F T Lake L K Gardner R A Sanchez 《The Journal of oral implantology》1992,18(4):372-378
The objectives of this study were: (a) to observe and describe the variability of bone healing in implant receptor sites which were prepared in rabbit femurs by use of different surgical methods; and (b) to determine if the animal model which was used was suitable for the detection of differences in healing reactions in implant receptor sites which were prepared by different surgical methods. Three 3-mm-wide implant receptor sites were prepared in the right and left femurs of four large New Zealand white rabbits. The surgical parameters used in preparation of the different sites included: low speed with no irrigation (LSO); low speed with internal irrigation only (LSI); low speed with external irrigation only (LSE); high speed with no irrigation (HSO); or high speed with external irrigation only (HSE). The sites were randomized so that each animal had one of each type of site in either the right or left femur. A non-treated control site was located in each animal for comparison with experimental sites. The animals were killed at 7, 14, 21, and 28 days post-operatively. The resultant samples were fixed, embedded, sectioned, and stained with basic fuchsin and toluidine blue. The results indicated that this was probably not a suitable animal model, since no discernible differences were detected in the various healed sites. 相似文献
10.
Abstract Mathematical models and computer-based engineering tools were used to evaluate the effect of a patent or closed apical foramen on stresses that are produced within gutta-percha during condensation. We examined a mathematical model of a tapered canal with a definite constriction and compared the results when the apical foramen was closed or open. When the canal was closed an almost constant stress was seen throughout the gutta-percha. When the foramen was open a sharp increase in lateral stress was observed in the apical portions of the canal. The constriction near the foramen caused the gutta-percha to be squeezed together and the stress was increased. This increases the likelihood that the gutta-percha is well adapted to the apical constriction. However, the stresses are also transferred to the surrounding dentin, resulting in a stress concentration near the apical foramen where the bulk of dentin is minimal. 相似文献