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   757篇
  免费   54篇
  国内免费   13篇
耳鼻咽喉   1篇
儿科学   44篇
妇产科学   9篇
基础医学   85篇
口腔科学   15篇
临床医学   123篇
内科学   143篇
皮肤病学   4篇
神经病学   13篇
特种医学   182篇
外科学   96篇
综合类   44篇
预防医学   18篇
眼科学   6篇
药学   11篇
  1篇
肿瘤学   29篇
  2021年   9篇
  2019年   3篇
  2018年   11篇
  2017年   2篇
  2016年   5篇
  2015年   10篇
  2014年   8篇
  2013年   3篇
  2012年   16篇
  2011年   22篇
  2010年   15篇
  2009年   14篇
  2008年   9篇
  2007年   27篇
  2006年   23篇
  2005年   30篇
  2004年   25篇
  2003年   37篇
  2002年   39篇
  2001年   21篇
  2000年   31篇
  1999年   28篇
  1998年   37篇
  1997年   27篇
  1996年   25篇
  1995年   31篇
  1994年   25篇
  1993年   34篇
  1992年   13篇
  1991年   13篇
  1990年   14篇
  1989年   21篇
  1988年   27篇
  1987年   36篇
  1986年   22篇
  1985年   24篇
  1984年   11篇
  1983年   14篇
  1982年   8篇
  1981年   12篇
  1980年   12篇
  1979年   1篇
  1978年   9篇
  1977年   5篇
  1976年   2篇
  1975年   6篇
  1974年   2篇
  1971年   1篇
  1947年   1篇
  1903年   1篇
排序方式: 共有824条查询结果,搜索用时 15 毫秒
1.
2.
Ten thrombocytopenic patients (platelets < 10–24 × 10(9)/L) who were refractory to platelet transfusion were investigated for their responsiveness to staphylococcal protein A column therapy. Nine patients had previously been treated with steroids, intravenous immune globulin, and/or other forms of immunosuppressive therapy without improvement in their transfusion response. All patients were receiving multiple platelet transfusions without achieving 1-hour corrected count increments (CCIs) > or = 7500. Eight patients had antibodies that reacted with platelets and were directed against HLA class I antigens, ABO antigens, and/or platelet-specific alloantigens. Plasma (500-2000 mL) from each patient was passed over a protein A silica gel column and then returned to the patient. Patients received from 1 to 14 treatments. A positive response to protein A therapy was defined as at least a doubling of the pretreatment platelet count and/or two successive 10- to 120-minute posttransfusion CCIs > or = 7500. Following plasma treatments, 6 of 10 patients responded with daily platelet counts that averaged 48 +/− 11 × 10(9) per L as compared with counts of 16 +/− 7 × 10(9) per L (p < 0.0005) before treatment. Posttransfusion CCI values determined in four of these patients averaged 2480 +/− 810 and 10,010 +/− 3540 (p < 0.005) before and after treatment, respectively. In contrast, among the four unresponsive patients, platelet counts averaged 10 +/− 9 and 13 +/− 10 × 10(9) per L (p = NS), respectively, while posttransfusion CCIs were 700 +/− 1410 and 1520 +/− 2460 (p = NS), respectively.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
3.
Results of clinical, contrast enema (CE), and computed tomographic (CT) examinations in 39 patients with perforated colorectal neoplasms were retrospectively reviewed. Twenty patients were toxemic at initial presentation, but in only four patients was the diagnosis of perforated colorectal neoplasm initially suspected clinically. CE study was performed in 22 patients and enabled the diagnosis of perforated neoplasm in 11 cases, neoplasm alone in eight, and neither neoplasm nor perforation in three. CT was performed in 38 patients and enabled the diagnosis of perforated neoplasm in 36; pericolic phlegmon but no mass lesion was evident in two. In 16 patients, CT also demonstrated metastatic disease. Because of its reliability in establishing the diagnosis and staging the extent of the inflammatory and neoplastic disease, CT is indicated in cases of suspected or proved perforated colorectal neoplasm and in cases in which CE study findings are indeterminate or suggestive of perforated neoplasm.  相似文献   
4.
We assessed in 1662 consecutive diabetic patients systolic arm-ankle indexes by a Doppler ultrasonic method. In those patients with indexes greater than or equal to 1.3 directional Doppler sonometry and mercury strain gauge plethysmography were performed. In some instancies electronic oscillography, duplex sonography and vital microscopy were additionally done. In 4.45% of the patients functional findings of a mediasclerosis could be encountered. Location of arterial mediacalcinosis was documented by x-ray examinations. Sensitivity of none invasive methods was merely 100%, specificity ranged from 96% (Dopplersonometry) to 80% (Duplexsonometry). In 18.9% an occlusive arterial disease could additionally be found. Mediasclerosis preferentially was encountered in Type II diabetics of older age. In this group painful distal neuropathy in many instances existed mimicking claudication, retinopathy and nephropathy was as frequent as in other diabetics. Normal or elevated Doppler indexes did not exclude occlusive arterial disease whereas diabetics with mediasclerosis and ulcero-gangreneous lesions or amputations in most of the cases did not have occlusive arterial disease.  相似文献   
5.
6.
7.
8.
9.
Intestinal obstruction proximal to a transition zone without an interposed physical barrier usually indicates Hirschsprung disease. The authors report one case of focal small bowel muscular thinning just distal to a transition zone that produced clinical and radiographic findings that simulated long-segment Hirschsprung disease in a 2-day-old infant.  相似文献   
10.
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