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   477篇
  免费   57篇
  国内免费   2篇
儿科学   18篇
妇产科学   7篇
基础医学   27篇
口腔科学   19篇
临床医学   30篇
内科学   162篇
皮肤病学   25篇
神经病学   19篇
特种医学   46篇
外科学   53篇
综合类   4篇
预防医学   15篇
眼科学   10篇
药学   49篇
肿瘤学   52篇
  2022年   2篇
  2021年   4篇
  2020年   4篇
  2019年   3篇
  2018年   7篇
  2017年   10篇
  2016年   5篇
  2015年   5篇
  2014年   17篇
  2013年   20篇
  2012年   28篇
  2011年   29篇
  2010年   10篇
  2009年   18篇
  2008年   24篇
  2007年   20篇
  2006年   17篇
  2005年   19篇
  2004年   23篇
  2003年   33篇
  2002年   18篇
  2001年   27篇
  2000年   29篇
  1999年   28篇
  1998年   5篇
  1997年   8篇
  1996年   15篇
  1995年   9篇
  1994年   6篇
  1993年   9篇
  1992年   9篇
  1991年   11篇
  1990年   6篇
  1989年   4篇
  1988年   7篇
  1987年   5篇
  1986年   5篇
  1985年   3篇
  1984年   4篇
  1983年   2篇
  1982年   6篇
  1978年   3篇
  1975年   2篇
  1974年   1篇
  1973年   3篇
  1972年   4篇
  1970年   2篇
  1969年   2篇
  1968年   1篇
  1946年   2篇
排序方式: 共有536条查询结果,搜索用时 31 毫秒
1.
2.
3.
Although the use of methotrexate (MTX) is gaining acceptance in the treatment of several connective tissue diseases, there is little evidence of its therapeutic value in systemic lupus erythematosus (SLE). We examined the response to MTX in patients with steroid-resistant SLE in an open, unblinded study. Of 10 SLE patients treated with MTX (7.5 mg/weekly), 7 showed improvement. The other 3 stopped therapy because of lack of response or because of side effects. Improvements were noted within 3 months in responding patients. These promising observations suggest that controlled studies of MTX for the treatment of SLE are justified.  相似文献   
4.
5.
Abstract – In order to evaluate trends in caries experience, a 20% random sample of 12-yr-old residents of Reykjavik, Iceland (252 children) was examined clinically and radiographically in 1991 under conditions consistent with those of the survey conducted in 1984. In addition to caries data, frequency of toothbrushing and use of fluoride dentifrice were recorded. The mean DFT and DPS were 3.0 and 4.1, respectively. The decrease in caries experience reached 60% with an annual fall in DPS of nearly 10%. During the 7-yr period between examinations the decline in DFT and DFS scores averaged 5.2 and 8, respectively, the annual reduction amounting to 0.7 DF teeth or 1.1 DF surfaces per child. The ratio of approximal/occlusal caries and the proportion of approximal caries were similar in both surveys. Fourteen percent of the children were free from manifest caries in 1991, but only 2% in 1984. Polarization between low and high prevalence individuals had intensified. Ninety-five percent of the children brushed their teeth regularly and 97% reported using a fluoride dentifrice.  相似文献   
6.
The radiological findings are described in four patients who developed strictures of the small bowel, and who had received non-steroidal, anti-inflammatory drugs (NSAIDs) for 1.5-15 years. Clinical presentation was that of subacute small bowel obstruction. Small bowel barium studies showed multiple discrete strictures. Some strictures were indistinguishable from those of regional enteritis. Others however were narrow "diaphragm-like" septae encroaching on and markedly narrowing the ileal lumen, and shown histologically to be due to submucosal fibrosis. It is suggested that these strictures are likely to be consequent on NSAIDs administration and that radiologists and surgeons need to be aware of these "diaphragms" which can be very difficult to detect on barium examination, either small bowel follow-through or enteroclysis, and at laparotomy.  相似文献   
7.
COX-inhibiting nitric oxide donators (CINODs) are a new class of drugs in development for the treatment of acute and chronic pain. They comprise a COX-inhibiting moiety linked to a nitric-oxide-donating component and are designed to provide an innovative mechanism of action of balanced COX inhibition and controlled nitric oxide donation. Through these pathways, CINODs should provide analgesic and anti-inflammatory efficacy, while offering gastrointestinal safety through the tissue-protective effects of nitric oxide donation. AZD3582 [4-(nitrooxy)butyl-(2S)-2-(6-methoxy-2-naphthyl)propanoate] is the first agent in the CINOD class to enter extensive clinical development. Pre-clinical studies demonstrate that AZD3582 has a superior gastrointestinal safety profile to naproxen, while demonstrating analgesic and anti-inflammatory efficacy. In healthy human volunteers, AZD3582 caused little gastrointestinal damage compared with equimolar doses of naproxen. Studies to evaluate the longer-term gastrointestinal safety of AZD3582, alongside its efficacy in alleviating chronic and acute pain, are ongoing.  相似文献   
8.
OBJECTIVE: Obesity is frequently reported in patients treated for childhood leukaemia. Obesity, particularly abdominal obesity, is one of the main characteristics of the metabolic syndrome and a risk factor for cardiovascular disease and non-insulin-dependent diabetes mellitus (NIDDM). DESIGN: All patients treated for acute lymphoblastic leukaemia (ALL) before the onset of puberty in the region of western Sweden, between 1973 and 1985, and in first remission, were included. 35 out of 47 patients aged 20-32 years participated. 19 patients had received cranial radiotherapy, and the median follow-up time was 20 years. The focus of this report was to study body composition and signs of the metabolic syndrome and correlate the findings to spontaneous growth hormone (GH) secretion. METHODS: Body composition was assessed using dual-energy X-ray absorbtiometry (DEXA). We analyzed serum concentrations of insulin, glucose, leptin and lipids. RESULTS: No patient was obese according to World Health Organization criteria (body mass index, BMI > or = 30 kg/m2) but one-third were overweight (BMI 25-29.9 kg/m2). The maximal GH peak during 24 h (GHmax) was correlated to percentage of total body fat (r = -0.42; P = 0.017), trunk fat (r = -0.5; P = 0.005) and fat-free mass (r = 0.42; P = 0.017). GHmax was also correlated to s-triglycerides (r = -0.54; P = 0.001), low-density lipoprotein-cholesterol (r = -0.382; P = 0.024) and high-density lipoprotein-cholesterol (r = 0.45; P = 0.007). CONCLUSIONS: We found little effect on BMI but an increased percentage of total body fat, especially trunk fat, and a tendency for an unfavourable lipid profile in adult survivors of childhood leukaemia. These findings were related to low endogenous GH secretion due to cranial irradiation.  相似文献   
9.
OBJECTIVE: The large intestine has been reported to have a capacity for iron absorption and expresses genes for iron absorption normally found in the duodenum. The importance and function of these genes in the large intestine are not understood. We therefore investigated the cellular localization and regulation of expression of these genes in mouse caecum and colon. MATERIAL AND METHODS: Gene expression was measured by real-time PCR using RNA extracted from iron-deficient and hypoxic mouse large intestine, compared to controls. Protein localization and regulation were measured by immunohistochemistry using frozen sections of the large intestine from the same mice. RESULTS: Dcytb (duodenal ferric reductase) was expressed at very low levels in the large intestine, compared to the duodenum, while Ireg1 and DMT1 were expressed at significant levels in the large intestine and were increased in iron-deficient caecum, proximal and distal colon, with the most significant increases seen in the distal colon. Hypoxia increased Ireg1 expression in the proximal colon. Immunohistochemistry detected significant levels of only IREG1, which was localized to the basolateral membrane of colonic epithelial cells. CONCLUSIONS: Iron absorption genes were expressed at lower levels in mouse caecum and colon than in the duodenum. They are regulated by body iron requirements. Colonic epithelial cells express basolateral IREG1in the same fashion as in the duodenum and this protein could regulate colonic epithelial cell iron levels.  相似文献   
10.
K Teahon  P Smethurst  A J Levi  I S Menzies    I Bjarnason 《Gut》1992,33(3):320-323
It has been reported that intestinal permeability to polyethylene glycol 400 is increased in patients with Crohn's disease and their apparently unaffected first degree relatives. Because of the implications that these findings have for the aetiology of Crohn's disease these studies were repeated. Patients with Crohn's disease (n = 28) and 32 first degree relatives from 11 families underwent a polyethylene glycol 400 (PEG400) intestinal permeability test and a hyperosmotic (1500 mosmol/l) absorption/permeability test using 3-0-methyl-D-glucose, D-xylose, L-rhamnose, lactulose, and 51chromium labelled ethylenediamine-tetraacetate. The five hour urine excretion of polyethylene glycol 400 did not differ significantly between controls (n = 25) and first degree relatives, 25.5 (3.3)% v 24.6% (4)% (mean(SD)) p greater than 0.1, respectively. Patients with small bowel involvement excreted significantly less (p less than 0.01) polyethylene glycol 400 (16.3 (4.6)% than controls while those with Crohn's colitis did not (26.4 (3.9)% p greater than 0.1). The permeation of the monosaccharides in patients with Crohn's disease and their first degree relatives did not differ from normal subjects. The permeation of lactulose and 51chromium ethylenediaminetetraacetate was not significantly altered in first degree relatives but was significantly increased in the patients, as was the lactulose/L-rhamnose urine excretion ratio which is a specific measure of small intestinal permeability. These studies show normal absorption and permeability in first degree relatives of patients with Crohn's disease. A genetically determined abnormality of intestinal permeability is not likely to be an important aetiological factor in Crohn's disease.  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