全文获取类型
收费全文 | 63571篇 |
免费 | 4680篇 |
国内免费 | 333篇 |
专业分类
耳鼻咽喉 | 644篇 |
儿科学 | 1608篇 |
妇产科学 | 1543篇 |
基础医学 | 7850篇 |
口腔科学 | 1537篇 |
临床医学 | 6396篇 |
内科学 | 14443篇 |
皮肤病学 | 809篇 |
神经病学 | 5015篇 |
特种医学 | 1932篇 |
外国民族医学 | 2篇 |
外科学 | 9865篇 |
综合类 | 1016篇 |
现状与发展 | 1篇 |
一般理论 | 103篇 |
预防医学 | 5273篇 |
眼科学 | 1858篇 |
药学 | 4445篇 |
中国医学 | 139篇 |
肿瘤学 | 4105篇 |
出版年
2023年 | 293篇 |
2022年 | 463篇 |
2021年 | 1155篇 |
2020年 | 729篇 |
2019年 | 1013篇 |
2018年 | 1247篇 |
2017年 | 849篇 |
2016年 | 975篇 |
2015年 | 1138篇 |
2014年 | 1779篇 |
2013年 | 2816篇 |
2012年 | 3782篇 |
2011年 | 4127篇 |
2010年 | 2349篇 |
2009年 | 2196篇 |
2008年 | 4016篇 |
2007年 | 4212篇 |
2006年 | 4041篇 |
2005年 | 4121篇 |
2004年 | 3848篇 |
2003年 | 3460篇 |
2002年 | 3429篇 |
2001年 | 741篇 |
2000年 | 634篇 |
1999年 | 724篇 |
1998年 | 741篇 |
1997年 | 611篇 |
1996年 | 494篇 |
1995年 | 493篇 |
1994年 | 466篇 |
1993年 | 442篇 |
1992年 | 544篇 |
1991年 | 521篇 |
1990年 | 422篇 |
1989年 | 443篇 |
1988年 | 402篇 |
1987年 | 378篇 |
1986年 | 360篇 |
1985年 | 426篇 |
1984年 | 439篇 |
1983年 | 397篇 |
1982年 | 533篇 |
1981年 | 448篇 |
1980年 | 493篇 |
1979年 | 308篇 |
1978年 | 333篇 |
1977年 | 330篇 |
1976年 | 272篇 |
1975年 | 296篇 |
1974年 | 254篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
221.
222.
585-nm Pulsed Dye Laser in the Treatment of Surgical Scars Starting on the Suture Removal Day 总被引:2,自引:0,他引:2
Keyvan Nouri MD Gloria P. Jimenez MD Catherine Harrison-Balestra BA George W. Elgart MD 《Dermatologic surgery》2003,29(1):65-73
BACKGROUND: The optimal time frame to improve the quality and cosmetic appearance of scars by laser therapy has not been clearly elucidated by prior controlled clinical trials. OBJECTIVE: To determine the efficacy of the 585-nm pulsed dye laser (PDL) in the treatment of surgical scars starting on the day of suture removal. METHODS: Eleven patients (skin types I-IV) with 12 postoperative linear scars that were greater than 2 cm were treated three times on monthly intervals with the 585-nm PDL (450 micro s, 10-mm spot size, 3.5 J/cm2 with 10% overlap) on one scar half, whereas the other half received no treatment. Scars were later evaluated by a blinded examiner using the Vancouver Scar Scale (VSS) for pigmentation, vascularity, pliability, and height. Scars were then blindly examined for cosmetic appearance using a visual analog scale. RESULTS: One month after the last treatment, final scar analysis by the blinded examiner revealed a significant difference between treated and untreated sites, with the treated halves scoring better in all scar parameters in the VSS and in cosmetic appearance. The treated halves demonstrated an overall average improvement in the VSS between the first treatment score and the final score of 54% versus 10% in the controls (P=0.0002). The cosmetic appearance score (0=worst; 10=best) at final assessment was significantly better for the treated scars, scoring 7.3 versus the averaged control score of 5.2 (P=0.016). CONCLUSION: The 585-nm PDL is effective and safe in improving the quality and cosmetic appearance of surgical scars in skin types I-IV starting on the day of suture removal. 相似文献
223.
224.
Lorraine V. Klerman Dr.P.H. Beth A. Baker M.S. George Howard Dr.P.H. 《The Journal of adolescent health》2003,32(6):452-455
This paper uses survival analysis to examine three large-scale, multi-site, randomized, controlled programs that attempted to prevent or delay second births to teenagers. Statistically significant differences in the hypothesized direction were found between the intervention and the control groups in the Elmira and Memphis Home Visitation sites. No statistically significant differences in the hypothesized direction were found in the Teen Parent Welfare Demonstration overall or in any of its three sites or in all New Chance sites combined. Delaying second pregnancies among teenagers requires intensive efforts. Survival analysis is a more accurate and useful way of presenting program results than simple analysis of the proportion of women with a second birth. 相似文献
225.
226.
227.
Hugh E. Criswell Darin J. Knapp David H. Overstreet George R. Breese 《Alcoholism, clinical and experimental research》1994,18(3):596-601
The effects of ethanol, chlordiazepoxide, and MK-801 on performance in the elevated-plus maze and on activity measured in a circular activity monitor were compared in Sprague-Dawley rats to determine whether these effects of ethanol could be explained by its action on either GABAA or NMDA receptors. Both ethanol and chlordiarepoxide produced an increase in the time spent in the open arms of the elevated-plus maze and in the ratio of open arm to total arm entries, indicative of an anxiolytic action of these drugs. MK-801 did not alter either the time spent in the open arms or the ratio of open to total arm entries. Chlordiazepoxide and MK-801 produced an increase in total arm entries that suggested that these compounds were increasing locomotor activity. Ethanol also increased total arm entries, but the effect was not statistically reliable. Following habituation to an activity monitor, neither ethanol nor chlordiazepoxide increased activity in this task, whereas MK-801 produced a robust increase in locomotion. Additionally, neither ethanol nor chlordiazepoxide blocked the MK-801-induced locomotor stimulation. The latter finding suggests that the effects of ethanol on GABAA receptors was not Mocking an increased activity level produced by its antagonism of NMDA. Additionally, these results indicate that the anxiolytic and locomotor action of ethanol in rats parallel the effects of a benzodiazepine and not those of an NMDA antagonist. Finally, these results suggest that the consequence of ethanol's antagonism of NMDA receptor function is more restricted than that produced by MK-801. 相似文献
228.
229.
The postoperative necrotizing sclerokeratitis is a rare condition occurring shortly after surgical procedures, mainly following cataract extractions. After several exacerbations and remissions spontaneous scleral perforation may occur. In the described case the conservative treatment/topical antibiotics, corticosteroids/failed, therefore the damaged scleral surface was covered with lyophilized dura and the condition came to a standstill. 相似文献
230.