首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   141421篇
  免费   11951篇
  国内免费   8414篇
耳鼻咽喉   1428篇
儿科学   1966篇
妇产科学   1126篇
基础医学   13843篇
口腔科学   2449篇
临床医学   16099篇
内科学   20562篇
皮肤病学   1606篇
神经病学   6899篇
特种医学   5955篇
外国民族医学   36篇
外科学   16244篇
综合类   26070篇
现状与发展   33篇
一般理论   13篇
预防医学   11300篇
眼科学   2672篇
药学   14155篇
  164篇
中国医学   8085篇
肿瘤学   11081篇
  2024年   1481篇
  2023年   2074篇
  2022年   4253篇
  2021年   5895篇
  2020年   4630篇
  2019年   3966篇
  2018年   3862篇
  2017年   4031篇
  2016年   4018篇
  2015年   5991篇
  2014年   7595篇
  2013年   7749篇
  2012年   11306篇
  2011年   12319篇
  2010年   9333篇
  2009年   7846篇
  2008年   9192篇
  2007年   9259篇
  2006年   8382篇
  2005年   7642篇
  2004年   5723篇
  2003年   5452篇
  2002年   4674篇
  2001年   3097篇
  2000年   2506篇
  1999年   1842篇
  1998年   1144篇
  1997年   1217篇
  1996年   818篇
  1995年   727篇
  1994年   598篇
  1993年   421篇
  1992年   423篇
  1991年   381篇
  1990年   303篇
  1989年   263篇
  1988年   211篇
  1987年   204篇
  1986年   191篇
  1985年   114篇
  1984年   96篇
  1983年   53篇
  1982年   42篇
  1981年   36篇
  1980年   46篇
  1979年   57篇
  1978年   41篇
  1975年   34篇
  1974年   32篇
  1973年   27篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
22.
23.
24.
25.
The beta-adrenoceptor (beta-AR)-stimulatory guanine nucleotide-binding (Gs) protein system has been shown to play important roles in the cardiovascular system. The gene encoding the alpha-subunit of Gs proteins (GNAS1) is a candidate genetic determinant for hypertension. Because alcohol consumption is known to affect blood pressure partly through the beta-AR-Gs protein system, we examined the possible interaction between GNAS1 T393C polymorphism and drinking status in the association with hypertension in the present study. As a result, a non-significant but reasonable trend supporting the presence of an interaction was shown (p = 0.076). In line with this trend, the T393C polymorphism significantly interacted with drinking status in the association with systolic blood pressure (p = 0.028). Moreover, supporting the presence of an interaction, T allele carriers consistently had a higher probability of hypertension, higher systolic blood pressure, and higher diastolic blood pressure than CC homozygotes in non-drinkers and light drinkers. In contrast, CC homozygotes consistently had a higher probability of hypertension, higher systolic blood pressure, and higher diastolic blood pressure than T allele carriers in moderate to heavy drinkers. The present study also showed a significant interaction between the T393C polymorphism and drinking status in the association with pulse pressure (p = 0.026), reflected by a significant association between the T393C polymorphism and pulse pressure in moderate to heavy drinkers (p = 0.026). These findings may be helpful in conducting further molecular and biological studies on the relationship among the effects of alcohol, the beta-AR-Gs protein system, and hypertension.  相似文献   
26.
27.
Amyloidosis is a systemic disease that usually occurs in the gastrointestinal tract or in muscular or adipose tissue. Primary amyloidosis of the urinary bladder is a rare disease that can mimic bladder cancer on cystoscopic examination as well as in its clinical presentation of painless gross hematuria. This report describes a 49-year-old male with repeated painless gross hematuria, who underwent transurethral resection of a suspected bladder tumor. Pathologic examination revealed papillary urothelial hyperplasia with vascular ectasia and no signs of malignancy. Massive gross hematuria occurred 2.5 years later. Cystoscopy showed multiple papillary lesions with yellowish-brown submucosal plaques on the posterior bladder wall. A second transurethral tumor resection was performed and histologic examination revealed plasma cell infiltration and eosinophilic amorphous deposits in the subepithelial stroma and vascular wall. The deposits were positive for Congo red and apple-green birefringence under polarized light examination but negative for Masson's trichrome stain, indicating that they were not fibrotic in nature. Hence, the diagnosis of amyloidosis of the urinary bladder was confirmed. Screening for amyloidosis was negative in other organ systems and the patient has remained disease-free up to the last follow-up 4 years after the second transurethral resection. Amyloidosis should be considered in the differential diagnosis of patients with recurrent hematuria who have symptoms characteristic of bladder cancer but negative pathologic study for malignancy. Correct diagnosis relies on clinical alertness and the use of a special staining technique during pathologic examination.  相似文献   
28.
处女膜修补手术及麻醉方法的改进   总被引:9,自引:7,他引:2  
目的;增大处女膜粘膜瓣的接触面,减少因麻醉造成的处女膜粘膜水肿,提高修复手术的成功率。方法:手术全部采用1%的卡因行粘膜表面麻醉。53例采用瓦合粘膜瓣法,3例用瓦合粘膜瓣联合阴道粘膜瓣修复法。结果:56例术后一月随访,53例处女膜孔径为一指,成功率94.64%。结论:采用1%的卡因粘膜表面麻醉,瓦合粘膜瓣法及瓦合粘膜联合阴道粘膜瓣修复法对处女膜修复是行之有效的。  相似文献   
29.
M K Fu 《中华口腔医学杂志》1992,27(6):354-5, 385
This system is composed of: (1) a perspective table, (2) TV camera, (3) a high-resolution image displayer, (4) a computer, (5) a laser printer The functions of this system are as follows: (1) It can perform cephalometries directly from image of X-ray film, (2) it can diagnose and analyse the deformity and provide treatment plan. This system is valuable for orthodontics and surgical orthodontics.  相似文献   
30.
李钧  张泺 《眼科研究》1990,8(3):156-158
应用神经组织化学技术观察了兔角膜NA能神经及AchE阳性神经在角膜损伤后的再生,证实术后1月,两种神经均有再生轴突进入植片;术后3月可见交界区和植床内神经密度明显增加;同时,对术后两种神经再生的功能意义进行了讨论。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号