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   174篇
  免费   10篇
儿科学   27篇
妇产科学   2篇
基础医学   18篇
口腔科学   1篇
临床医学   9篇
内科学   45篇
皮肤病学   8篇
神经病学   3篇
特种医学   21篇
外科学   20篇
综合类   4篇
预防医学   4篇
眼科学   3篇
药学   7篇
中国医学   1篇
肿瘤学   11篇
  2023年   1篇
  2022年   1篇
  2021年   4篇
  2018年   1篇
  2017年   2篇
  2016年   3篇
  2015年   2篇
  2014年   2篇
  2013年   7篇
  2012年   5篇
  2011年   3篇
  2010年   11篇
  2009年   13篇
  2008年   2篇
  2007年   5篇
  2006年   6篇
  2005年   3篇
  2004年   1篇
  2003年   2篇
  2002年   1篇
  2000年   4篇
  1999年   3篇
  1998年   12篇
  1997年   6篇
  1996年   14篇
  1995年   6篇
  1994年   13篇
  1993年   11篇
  1992年   1篇
  1991年   1篇
  1990年   3篇
  1989年   4篇
  1988年   4篇
  1987年   2篇
  1986年   1篇
  1985年   3篇
  1984年   1篇
  1983年   3篇
  1982年   3篇
  1981年   2篇
  1980年   1篇
  1978年   1篇
  1977年   1篇
  1976年   4篇
  1975年   2篇
  1974年   2篇
  1955年   1篇
排序方式: 共有184条查询结果,搜索用时 15 毫秒
131.
Ectopic pregnancy: duplex Doppler evaluation   总被引:3,自引:0,他引:3  
Of 398 patients in whom there was a clinical suspicion of ectopic pregnancy, 96 (24%) were found to have the condition. Of the 96, 70 underwent duplex Doppler imaging. A viable ectopic fetus was seen in 10 of 70 (14%), and an extrauterine sac without an identifiable fetus was seen in an additional 27, giving a sensitivity for imaging alone of 53%. Fetal heart activity was detected with Doppler in 13 (19%). High-velocity flow, which suggested the presence of an ectopic pregnancy, was detected in 38 of 70 (54%) patients (total preoperative sensitivity, 73%). In the 91 patients who did not have an ectopic pregnancy, duplex Doppler imaging of the intrauterine contents alone allowed an ectopic pregnancy to be excluded in 29 (32%) on the first examination and in a further 21 on the second scan (specificity, 55%). Nine vascular adnexal masses were falsely considered to be ectopic pregnancies (specificity, 90%). The positive predictive values were 47% for imaging alone and 85% for Doppler. The negative predictive values were 60% for imaging alone and 81% for Doppler.  相似文献   
132.
133.
134.
Haug  PJ; Tocino  IM; Clayton  PD; Bair  TL 《Radiology》1987,164(3):747-752
We designed an automated system for managing large-scale screening and diagnostic mammography. The system collects coded mammographic findings from the radiologist and records a history directly from the patient. This information is stored in an integrated clinical data base to which the results of subsequent examinations or surgery are added. In addition, the system generates letters to the patient and her physician that describe mammographic findings and letters reminding them of routine screening visits. For patients who have positive results on examinations, it checks for records of biopsy or repeat mammography and generates follow-up letters if appropriate intervention is not found. While this system is part of a comprehensive computerized hospital information system, mammography management tools with most of the features described can be designed for relatively inexpensive microcomputers.  相似文献   
135.
136.
Adnexal and cul-de-sac abnormalities: transvaginal sonography   总被引:1,自引:0,他引:1  
Lande  IM; Hill  MC; Cosco  FE; Kator  NN 《Radiology》1988,166(2):325-332
Sixty-seven patients selectively chosen from 354 undergoing conventional transabdominal (TA) sonography for evaluation of a clinically suspected adnexal mass subsequently underwent transvaginal (TV) sonography either because the TA sonograms were technically suboptimal or because it was not possible to characterize with certainty an abnormality identified with TA sonography. TV sonography added diagnostically useful information in 25 of 28 patients with cystic pathologic changes in the adnexa uteri. Eight of 12 patients with tuboovarian abscess and nonspecific adnexal masses visualized with TA sonography had tube-shaped fluid collections characteristic of pyosalpinx identified with TV sonography. TV sonography added diagnostically useful information in all seven patients with diseases of the cul-de-sac (rectouterine fossa) and allowed differentiation of adnexal from primary uterine disease in three patients with TA sonograms on which findings were equivocal. It also expedited the diagnosis of a tubal pregnancy in ten of 14 patients and was useful in the detection of adhesions and perforated intrauterine devices. These results indicate that adjunctive TV sonography can provide important diagnostic information.  相似文献   
137.
Self‐expanding metallic stents for the treatment of acute colonic obstruction is a recent technique showing promising results. Traditionally metallic stents have used a colonoscope as the portal for stent insertion. Our rectal guiding tube has been devised to enable continuous opacification of the colon without contrast or colonic content leakage and provide a rigid portal through which to insert the metallic stent safely. In many situations concomitant use of a colonoscope is not necessary, especially in left‐sided or more distal colonic lesions.  相似文献   
138.
139.
BACKGROUND: Controlling lung inflammation may be the key to improving morbidity and mortality in cystic fibrosis. OBJECTIVE: To assess the effects of inhaled corticosteroids on lung inflammation in cystic fibrosis. DESIGN: Double blind placebo controlled randomised sequence crossover trial. Fluticasone propionate (400 micrograms/day) was given as a dry powder inhaler for six weeks with a four week washout period before crossover. OUTCOME MEASURES: Sputum inflammatory markers (interleukin-8, tumour necrosis factor-alpha (TNF-alpha) and neutrophil elastase-both free and bound to alpha 1-antiprotease), sputum interleukin-10, lung function, and symptomatology. SUBJECTS: Twenty three children from a regional cystic fibrosis centre were enrolled into the study, with mean age 10.3 years (range 7 to 17 years) and mean baseline forced expiratory volume in one second (FEV1) of 64% (range 21% to 102%) predicted for sex and height. One patient was excluded for non-compliance to the study protocol. RESULTS: No significant benefit was shown for the use of fluticasone propionate in any of the outcomes. For sputum interleukin-8 there was an estimated true treatment median difference of 142 pg/ml (95% confidence interval (CI) 8 to 2866 pg/ml) in favour of placebo; while for maximal expiratory flow at 25% (MEF25%) remaining forced vital capacity predicted for sex and height there was a 15 percentage points (pp) (95% CI 4 to 26 pp) mean treatment difference in favour of placebo. Sputum interleukin-10 was undetected in any samples and unaffected by fluticasone propionate. Neither atopic status, baseline FEV1, nor concomitant DNase therapy had any effect on response to treatment. CONCLUSIONS: Lack of benefit from fluticasone propionate was most likely due to failure of the drug to penetrate the viscid mucus lining the airways. It is suggested a large multicentre trial with higher doses given for a longer time by a different delivery system is required to assess efficacy.  相似文献   
140.
Collecting complete, timed stool samples for the estimation of faecal fat from infants wearing nappies is difficult. A gravimetric method has been adapted by applying a chloroform/methanol homophasic solvent system to extract lipids from whole soiled nappies. In a study of 22 collections in six infants, no stools were lost and the recovery of lipids was 96%, with results similar to a reference titrimetric method. In addition to total fat, individual lipids were measured using gas-liquid chromatography. The method simplifies stool collection and analysis, is aesthetically more acceptable, and leads to reduced microbial hazards. It also allows the detailed study of excreted lipid species enabling the coefficient of absorption of dietary lipids of various chain lengths to be determined individually.  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