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   499篇
  免费   33篇
  国内免费   13篇
耳鼻咽喉   1篇
儿科学   34篇
妇产科学   8篇
基础医学   54篇
口腔科学   11篇
临床医学   35篇
内科学   72篇
皮肤病学   20篇
神经病学   11篇
特种医学   138篇
外科学   55篇
综合类   21篇
预防医学   21篇
眼科学   6篇
药学   28篇
中国医学   1篇
肿瘤学   29篇
  2022年   2篇
  2021年   8篇
  2020年   4篇
  2019年   6篇
  2018年   7篇
  2017年   3篇
  2016年   5篇
  2015年   15篇
  2014年   8篇
  2013年   13篇
  2012年   4篇
  2011年   16篇
  2010年   24篇
  2009年   31篇
  2008年   14篇
  2007年   24篇
  2006年   18篇
  2005年   20篇
  2004年   20篇
  2003年   10篇
  2002年   9篇
  2001年   16篇
  2000年   6篇
  1999年   2篇
  1998年   20篇
  1997年   36篇
  1996年   21篇
  1995年   22篇
  1994年   16篇
  1993年   6篇
  1992年   4篇
  1991年   1篇
  1990年   8篇
  1989年   13篇
  1988年   9篇
  1987年   16篇
  1986年   9篇
  1985年   11篇
  1984年   5篇
  1983年   9篇
  1982年   7篇
  1981年   9篇
  1980年   12篇
  1979年   1篇
  1978年   4篇
  1977年   7篇
  1976年   8篇
  1975年   5篇
  1974年   1篇
排序方式: 共有545条查询结果,搜索用时 0 毫秒
41.
42.

Background

To correlate the metabolic changes with size changes for tumor response by concomitant PET-CT evaluation of lung cancers after radiotherapy.

Methods

36 patients were studied pre- and post-radiotherapy with18FDG PET-CT scans at a median interval of 71 days. All of the patients were followed clinically and radiographically after a mean period of 342 days for assessment of local control or failure rates. Change in size (sum of maximum orthogonal diameters) was correlated with that of maximum standard uptake value (SUV) of the primary lung cancer before and after conventional radiotherapy.

Results

There was a significant reduction in both SUV and size of the primary cancer after radiotherapy (p < 0.00005). Among the 20 surviving patients, the sensitivity, specificity, and accuracy using PET (SUV) were 94%, 50%, 90% respectively and the corresponding values using and CT (size criteria) were 67%, 50%, and 65% respectively. The metabolic change (SUV) was highly correlated with the change in size by a quadratic function. In addition, the mean percentage metabolic change was significantly larger than that of size change (62.3 ± 32.7% vs 47.1 ± 26.1% respectively, p = 0.03)

Conclusion

Correlating and incorporating metabolic change by PET into size change by concomitant CT is more sensitive in assessing therapeutic response than CT alone.  相似文献   
43.
44.
45.
In a case-control study to understand the risk factors for development of life-threatening dehydration, a total of 379 children comprising 243 cases (moderate or severe dehydration) and 136 controls (non or mild dehydration) up to 2 years of age suffering from acute watery diarrhoea were studied. By univariate analysis, the presence of vibrios in stool, withdrawal of breast feeding during diarrhoea, not giving fluids, including oral rehydration solution (ORS), during diarrhoea, frequent purging (> 8/ day), vomiting (> 2/day) and undernutrition were identified as risk factors. However, by multivariate analysis after controlling for confounders, withdrawal of breast feeding during diarrhoea (odds ratio (OR) = 6.8, p < 0.00001) and not giving ORS during diarrhoea (OR = 2.1, p < 0.006) were identified as significant risk factors. The confounding variables which also contributed significantly to increasing the risk were age (≤ 12 months; OR = 2.7, p = 0.001), frequent purging (> 8/day; OR = 4.1, p < 0.00001), vomiting (> 2/day; OR = 2.4, p = 0.001) and severe undernutrition (%median <60 weight-for-age of Indian Academy of Paediatrics classification; OR = 3.1, p = 0.001). We feel that these findings will be useful for Global and National Diarrhoeal Diseases Control Programmes for formulating intervention strategies for preventing death due to diarrhoeal dehydration.  相似文献   
46.
47.
Background  Bacterial overgrowth may cause cobalamin deficiency through competition for dietary cobalamin in the small intestine. The objective of this study was to prospectively determine the prevalence of small bowel bacterial overgrowth in patients with documented cobalamin deficiency in a tertiary referral centre.
Methods  Patients identified with cobalamin deficiency underwent diagnostic investigations including: Endoscopy (with gastric antrum, gastric body and duodenal biopsies and duodenal aspirate), 14C-D-Xylose breath test, intrinsic factor antibody, anti-endomysial antibody and red cell folate level. 'Definite' small bowel bacterial overgrowth was defined as either a positive 14C-D-Xylose breath test or > 100 000 CFU/mL of culture of duodenal aspirate. 'Suspected' small bowel bacterial overgrowth was defined as an elevated red cell folate in the absence of supplemental folate therapy.
Results  Over a 2-year period, 62 patients with cobalamin deficiency were identified, of whom, 26 (42%) had 'definite' small bowel bacterial overgrowth, whilst a further nine (15%) had 'suspected' small bowel bacterial overgrowth. Nineteen (31%) had pernicious anaemia, and no cause for cobalamin deficiency could be found in eight (13%) patients. The diagnosis found in the remaining patients included coeliac disease (4), Crohn's Disease (1), gastric resection (2), vegan (2), homozygotes of the MTHFR gene (C677T) mutation (2), and one had enteropathy associated with common variable immunodeficiency (CVID). 'Definite' small bowel bacterial overgrowth was found to coexist with nine of the 19 cases of pernicious anaemia, two coeliac subjects, one CVID enteropathy and one patient with the MTHFR gene mutation.
Conclusion  Small bowel bacterial overgrowth is commonly associated with cobalamin deficiency.  相似文献   
48.
Ohne Zusammenfassung  相似文献   
49.
Abstrakt 1. Hinsichtlich der Frage der Anerkennung einer Heilmethode kommt es nicht darauf an, ob eine Methode von der überwiegenden Mehrheit der sogenannten Schulmediziner anerkannt wird, aber auch nicht, ob die betreffende Methode „therapieimmanent“, also von denjenigen, die diese Methode entwickelt haben oder sie anwenden, als wirksam eingesch?tzt wird. Entscheidend ist vielmehr auf die Anerkennung derjenigen Personen abzustellen, die sich von dritter Seite als Wissenschaftler in einem wissenschaftlichen Verfahren mit der Frage der Wirksamkeit der betreffenden Methode auseinandergesetzt haben. 2. Der Wirkmechanismus der Bioresonanztherapie ist nach strengen naturwissenschaftlichen Untersuchungen nicht zu erkl?ren. Diese Methode ist jedoch von der Hufelandgesellschaft, die sich aus 25 ?rztegesellschaften zusammensetzt, die allesamt auch Naturheilverfahren betreiben, anerkannt. (Leits?tze des Bearbeiters)  相似文献   
50.
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