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   8319篇
  免费   716篇
  国内免费   70篇
耳鼻咽喉   102篇
儿科学   163篇
妇产科学   237篇
基础医学   1163篇
口腔科学   195篇
临床医学   848篇
内科学   1534篇
皮肤病学   198篇
神经病学   708篇
特种医学   310篇
外科学   1222篇
综合类   391篇
一般理论   2篇
预防医学   585篇
眼科学   217篇
药学   714篇
  2篇
中国医学   91篇
肿瘤学   423篇
  2023年   53篇
  2022年   79篇
  2021年   163篇
  2020年   117篇
  2019年   136篇
  2018年   174篇
  2017年   147篇
  2016年   131篇
  2015年   195篇
  2014年   221篇
  2013年   388篇
  2012年   441篇
  2011年   437篇
  2010年   300篇
  2009年   256篇
  2008年   339篇
  2007年   382篇
  2006年   348篇
  2005年   331篇
  2004年   306篇
  2003年   292篇
  2002年   287篇
  2001年   257篇
  2000年   262篇
  1999年   210篇
  1998年   101篇
  1997年   83篇
  1996年   52篇
  1995年   82篇
  1994年   73篇
  1993年   70篇
  1992年   174篇
  1991年   196篇
  1990年   157篇
  1989年   155篇
  1988年   147篇
  1987年   159篇
  1986年   147篇
  1985年   143篇
  1984年   115篇
  1983年   98篇
  1982年   71篇
  1981年   49篇
  1980年   59篇
  1979年   111篇
  1978年   77篇
  1977年   63篇
  1976年   60篇
  1975年   50篇
  1973年   46篇
排序方式: 共有9105条查询结果,搜索用时 15 毫秒
1.
目的 建立蒙药绿松石的质量标准。方法 收集不同产地绿松石,共10批。观察绿松石样品和粉末的性状并进行理化鉴别;按2020年版《中国药典》(四部)通则方法测定绿松石样品中水分、浸出物含量;采用原子吸收光谱法测定绿松石样品铜元素含量。结果 绿松石为不规则、周围带有黑石的块状物,表面蓝绿色,体重,质硬脆,难砸碎,断面呈贝壳状,蜡样光泽,粉末呈灰绿色,无臭,味淡;理化鉴别结果显示,呈铜盐反应;10批次样品中水分含量为0.41%-3.94%(SD=1.37%),浸出物含量为0.21%-0.81%(SD=0.21%),铜元素含量为3.03%-4.63%(SD=0.63%)。结论 初步拟定绿松石中水分含量不得超多5.0%、浸出物含量不得低于0.10%,铜元素含量应为2.60%-4.84%,制定的标准可用于蒙药材绿松石的质量控制。  相似文献   
2.
3.
Transplanting the Highly Sensitized Patient: The Emory Algorithm   总被引:4,自引:0,他引:4  
Renal transplant patients sensitized to HLA antigens comprise nearly one-third of the UNOS wait-list and receive 14% of deceased donor (DD) transplants, a rate half that of unsensitized patients. Between 1999 and 2003, we performed 492 adult renal transplants from DD; 120 patients (approximately 25%) had a panel reactive antibody (PRA) of >30%, with nearly half (n = 58) having a PRA of >80%. Our approach is based upon high-resolution solid-phase HLA antibody analysis to identify class I/II antibodies and a 'virtual crossmatch' to predict compatible donor/recipient combinations. Recipients are excluded from the United Network for Organ Sharing match run if donors possess unacceptable antigens. Thus, when sensitized patients appear on the match run, they have a high probability of a negative final crossmatch. Here, we describe our 5-year experience with this approach. Five-year graft survival ranged from 66% to 70% among unsensitized (n = 272), moderately sensitized (PRA < 30%, n = 100) and highly sensitized (>30% PRA; n = 120) patients, equal to the average national graft survival (65.7%). The application of this approach (the Emory Algorithm) provides a logical and systematic approach to improve the access of sensitized patients to DD organs and promote more equitable allocation to a highly disadvantaged group of patients awaiting renal transplantation.  相似文献   
4.
5.
目的 观察优克龙 (Urocalun )治疗输尿管结石的疗效和安全性。 方法 对 6 0例输尿管结石直径 <1cm的患者予口服优克龙治疗 ,4 5 0mg/次 ,3次 /d ,服药 5周。 结果  6 0例患者中结石排出 4 5例 (75 % ) ;10例 (17% )结石位置下降 ;5例 (8% )位置无变化。 4例患者服药后有轻度胃部不适、恶心或口干。 结论 优克龙治疗输尿管结石效果良好。  相似文献   
6.
Clinical versus ultrasonographic evaluation of scrotal disorders   总被引:1,自引:0,他引:1  
Clinical and ultrasonographic examinations of scrotal disorders were compared in 166 patients in order to determine their ability to distinguish between those diseases requiring surgery and those requiring clinical follow-up only. Ultrasound examinations were efficient in discriminating between normal and pathological findings. Extra-testicular lesions were readily differentiated from testicular ones. Although both clinical and ultrasonographic examinations had high sensitivity (90%) in detecting testicular cancer, the number of false positive findings was smaller after ultrasound examination. This gave a predictive value of a positive test of 53% after ultrasound examination but only 33% after clinical examination. Ultrasound examination may, therefore, reduce the number of surgical explorations in the scrotum and should be performed in patients with suspected testicular pathology based on history and palpatory findings.  相似文献   
7.
To measure prefrontal and subcortical activity during a cognitive task, we examined 19 newly diagnosed schizophrenics and patients with schizophreniform psychosis. Seven healthy volunteers served as controls. The patients were drug naive or had received neuroleptics for a few days only. Cerebral blood flow distribution was depicted by single photon emission computed tomography at rest and during activation with the Wisconsin Card Sorting Test. A significant relative activation deficit in the left inferior-prefrontal region was revealed during the Wisconsin Card Sorting Test in the patient group. Furthermore, the patients had impaired striatal suppression on the left side during the cognitive task. The test performance was significantly impaired in the patients. The inability to reduce striatal activity may be due to a lack of corticostriatal feedback during prefrontal activation.  相似文献   
8.
9.
Recurrent hip dislocation in intermediate spinal atrophy   总被引:1,自引:0,他引:1  
Recurrent hip dislocation after corrective orthopaedic surgery in children and teenagers with intermediate spinal atrophy has not been reported in the literature. Four cases with long-term follow-up are presented. These represent the only cases surgically treated in 30 years of following spinal atrophy patients. Thus, it seems significant that all hips redislocated after the surgical procedure. In addition, two patients had second operations with subsequent dislocation. Pelvic obliquity should not be the basis for the surgery, as spinal fusion is generally necessary for wheelchair users. The sagacity of performing surgery for hip dislocations is raised.  相似文献   
10.
The time aspects of daily use of a clinical database system in an endoscopy department were studied. The SADE database system for endoscopic procedures was introduced for daily use at Ullev?l Hospital on 1 January 1989. The average weekly programme of the endoscopy unit includes 57 gastroduodenoscopies, 23 colonoscopies and 12 ERCP/EPTs. During three consecutive weeks of the study the mean physician input time was 4 min 17 sec per patient (range 57 sec to 15 min), individual variation depending mainly on the extent of the report. Assistants spent a mean time of 4 min 23 sec for each patient. Thus, a total of 8 min 40 sec was spent for every patient seen. Endoscopic units should analyze their routines and needs before introducing an electronic data base manager.  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