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   2071篇
  免费   68篇
  国内免费   1篇
耳鼻咽喉   24篇
儿科学   63篇
妇产科学   81篇
基础医学   200篇
口腔科学   24篇
临床医学   258篇
内科学   525篇
皮肤病学   42篇
神经病学   81篇
特种医学   38篇
外科学   274篇
综合类   144篇
一般理论   3篇
预防医学   170篇
眼科学   22篇
药学   159篇
肿瘤学   32篇
  2013年   15篇
  2011年   9篇
  2010年   26篇
  2009年   27篇
  2008年   12篇
  2006年   9篇
  2002年   9篇
  1999年   20篇
  1998年   29篇
  1997年   41篇
  1996年   60篇
  1995年   40篇
  1994年   37篇
  1993年   39篇
  1992年   35篇
  1991年   29篇
  1990年   31篇
  1989年   42篇
  1988年   35篇
  1987年   23篇
  1986年   40篇
  1985年   30篇
  1984年   19篇
  1983年   26篇
  1982年   18篇
  1981年   23篇
  1980年   16篇
  1979年   18篇
  1978年   14篇
  1976年   22篇
  1975年   12篇
  1974年   9篇
  1970年   8篇
  1969年   8篇
  1968年   16篇
  1965年   12篇
  1963年   31篇
  1962年   9篇
  1961年   11篇
  1960年   9篇
  1959年   112篇
  1958年   184篇
  1957年   173篇
  1956年   175篇
  1955年   155篇
  1954年   132篇
  1949年   66篇
  1948年   105篇
  1947年   10篇
  1946年   8篇
排序方式: 共有2140条查询结果,搜索用时 15 毫秒
1.
2.
3.
Objectives Compare the effect of high doses of inhaled corticosteroids on bone loss in subjects with moderate to severe asthma or mild asthma, and examine the influence of dietary intake on bone metabolism. Design A survey on the effects of corticotherapy and nutrition on bone density was conducted in 74 subjects currently being treated for asthma in the asthma clinic of Hospital Laval (Sainte-Foy, Quebec, Canada). Fifty-eight subjects completed the study (attrition RATE=15%).

Main outcome measures In all subjects expiratory volumes were determined and urinary analysis was conducted for hydroxyproline, calcium, phosphorus, and cortisol levels. Osteocalcin, calcium, phosphorus, cortisol, alkaline phosphatase, and γ-glutamyltransferase levels were measured in blood samples. Bone density of the lumbar spine was determined by means of dual-energy x-ray absorptiometry. Nutrition evaluation was based on a 3-day food diary analyzed using progiciel Nutri 91. The nutritional parameters examined were calcium; phosphorus; magnesium; zinc; vitamins A, C, and D; protein; total fiber; oxalates; energy; caffeine; and alcohol in relation to bone density.

Subjects Thirty-one patients with moderate to severe asthma who had been taking more than 1,000 μg beclomethasone per day or the equivalent for more than 2 years and 27 patients with mild asthma who were taking less than 500 μg beclomethasone per day or the equivalent.

Statistical analyses performed Four factor analysis of variance with hierarchized interactions of four levels, Duncan's test, Pearson correlation coefficients.

Results Blood levels of osteocalcin and protein intake were lower in patients with moderate to severe asthma than in those with mild asthma (P<.05). Significant correlations (P<.02) were observed between bone density and calcium intake (r=.40), phosphorus intake (r=.35), protein intake (r=.30), and serum alkaline phosphatase level (r=−.30). Bone density was not significantly different between the two groups of patients with asthma.

Applications A follow-up of patients with asthma who are taking inhaled corticosteroids is needed to assess bone density, osteocalcin levels, and dietary intakes of calcium. Verify if osteocalcin level decreases over time in patients with moderate to severe asthma, monitor possible modifications in bone density, and verify if the correlation between dietary calcium and bone density is maintained. J Am Diet Assoc. 1997;97:1401–1406.  相似文献   

4.
The distribution in renal tumours of 3-fucosyl-N-acetyl lactosamine has been studied by using the monoclonal antibodies AGF 4.36 and AGF 4.48 and immunoperoxidase methods on tissue sections. Seven of 19 nephroblastomas and 12 of 30 renal cell carcinomas contained the epitope. In nephroblastomas the epitope was found on the terminals of type B tubules in six cases and in one case on the type A or neoplastic tubules. In renal carcinoma the antigen was found on the surface of tumour cells. The results suggest that in kidneys bearing nephroblastomas ureteric bud elements may grow into the tumour from the adjacent kidney.  相似文献   
5.
6.
7.
8.
9.
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