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   433篇
  免费   23篇
  国内免费   19篇
儿科学   38篇
妇产科学   11篇
基础医学   46篇
口腔科学   8篇
临床医学   49篇
内科学   78篇
皮肤病学   14篇
神经病学   11篇
特种医学   111篇
外科学   35篇
综合类   10篇
预防医学   19篇
眼科学   9篇
药学   14篇
中国医学   2篇
肿瘤学   20篇
  2021年   1篇
  2020年   5篇
  2019年   4篇
  2018年   10篇
  2017年   4篇
  2016年   6篇
  2015年   7篇
  2014年   10篇
  2013年   12篇
  2012年   6篇
  2011年   12篇
  2010年   15篇
  2009年   21篇
  2008年   11篇
  2007年   18篇
  2006年   7篇
  2005年   9篇
  2004年   5篇
  2003年   3篇
  2002年   4篇
  2001年   7篇
  2000年   3篇
  1999年   10篇
  1998年   31篇
  1997年   38篇
  1996年   28篇
  1995年   18篇
  1994年   17篇
  1993年   18篇
  1992年   2篇
  1991年   7篇
  1990年   11篇
  1989年   20篇
  1988年   12篇
  1987年   9篇
  1986年   8篇
  1985年   10篇
  1984年   4篇
  1983年   8篇
  1982年   6篇
  1981年   2篇
  1980年   11篇
  1979年   1篇
  1978年   1篇
  1977年   6篇
  1976年   7篇
  1975年   5篇
  1974年   2篇
  1970年   1篇
  1968年   1篇
排序方式: 共有475条查询结果,搜索用时 0 毫秒
31.

BACKGROUND:

The fecal occult blood test (FOBT), widely used as a colorectal cancer screening tool, continues to be used in hospitalized patients. However, the utility of this test for hospitalized patients is unclear.

OBJECTIVE:

To assess FOBT use in a large urban regional health authority.

METHODS:

Reports of all FOBTs performed between April 1, 2011 and March 30, 2012 from two academic and four community hospitals in Winnipeg (Manitoba) were extracted. Of 650 hospitalizations with a positive FOBT result and 1254 with a negative FOBT result, random samples of 230 and 97 charts, respectively, were reviewed. Information including demographics, admission diagnos(es), indication(s) for ordering the FOBT and clinical management was extracted.

RESULTS:

Thirty-four percent (650 of 1904) of hospitalizations with an FOBT had a positive FOBT result. Family medicine physicians ordered approximately one-half of the reviewed FOBTs. The most common indication for ordering an FOBT was anemia. Of those with a positive FOBT, 66% did not undergo further gastrointestinal investigations. Of those with a positive FOBT and overt gastrointestinal bleeding and/or melena who underwent endoscopy, 60% had their endoscopy performed before the FOBT result being reported while 38% underwent their endoscopy ≥3 days after the stool sample was collected. There were minimal differences in clinical practices between academic and community hospitals.

CONCLUSIONS:

The present study suggests that FOBT results in hospitalized patients may have little beneficial impact on clinical management. Hospital laboratories may be better served in directing resources to other tests.  相似文献   
32.
Human myeloperoxidase gene expression in acute leukemia   总被引:2,自引:0,他引:2  
Zaki  SR; Austin  GE; Swan  D; Srinivasan  A; Ragab  AH; Chan  WC 《Blood》1989,74(6):2096-2102
  相似文献   
33.
BACKGROUND: There are many advantages of breast milk for infants. Many factors can affect the volume and composition of breast milk. One of them is the maternal diet. The objective of this study is to determine the effect of Ramadan fasting on maternal nutrition and breast milk composition. METHODS: A total of 21 breast-feeding mothers aged between 17 and 38 years who fasted during Ramadan month and volunteered to give milk samples were surveyed. The ages of the infants were between 2 and 5 months. The study was performed during Ramadan and 2 weeks after the end of Ramadan. RESULTS: The results showed that during Ramadan, zinc, magnesium and potassium levels in breast milk decreased significantly (P<0.05). The mother's weight increased approximately 1 kg after Ramadan. Changes in body mass index of the mother were not statistically significant. A significant decrease in vitamin A intake was observed after Ramadan (P < 0.05). During Ramadan, energy and most nutrient intakes except protein and vitamins A and C were found below daily recommended dietary allowances necessary for lactating women. CONCLUSIONS: Ramadan fasting had no significant effect on the macronutrient composition of the breast milk and consequently the growth of the infants. There were significant differences in some of the micronutrients such as zinc, magnesium and potassium. The nutritional status of lactating women was affected by Ramadan fasting. All of the nutrient intakes (except vitamins A, E and C) decreased during Ramadan. For these reasons, it would seem prudent to excuse lactating women from fasting during Ramadan.  相似文献   
34.
35.
Speech-controlled generation of radiology reports   总被引:1,自引:0,他引:1  
Voice entry has been successfully employed to generate radiology reports with a word recognizer with a 1,000-word lexicon capacity. About 50% of reports were able to be dictated with a single 900-word lexicon. This was split into five sections by anatomic or subspecialty application. Each was augmented to 900 words. By switching from one lexicon to another, it was possible to dictate more than 70% of reports. With exclusive use of three lexicons in subspecialty areas (gastrointestinal radiology, neuroradiology, and mammography), and with further modification of the respective vocabulary, it has been possible to employ the system 88% of the time. Twelve percent of cases included wording that was beyond the scope of the lexicon. Computer subsets that allow different translations of some words when used in different contexts have been used. Some of these are used as triggers that will print whole lines, sentences, or even complete reports. Dictation times with voice entry take about 20% longer. Recognition reliability has been greater than 95%.  相似文献   
36.
It is common to encounter patients with coexisting aortic arch aneurysm and abdominal aortic lesions. We conducted simultaneous total arch replacement and abdominal aortic surgery in 3 patients having such lesions. Mean operative time was 511 minutes and no in-hospital mortality occurred. Postoperative respiratory failure was observed in an 80-year-old patient who recovered and all three patients were discharged in good condition. No other postoperative complication was seen. Simultaneous total arch replacement and abdominal aortic surgery may thus offer advantages to patients with such double aortic lesions if it can be conducted safely.  相似文献   
37.
Securinega virosa is used traditionally as sedative in children and in mental illnesses. In this study, the behavioral effects of methanolic root bark extract of S. virosa were investigated in mice. The results revealed that the extract significantly (P<0.05) and dose-dependently reduced the onset and prolonged the duration of sleep. The extract significantly (P<0.05) decreased exploratory activity and reduced the rate of apomorphine-induced stereotyped climbing at the doses tested (6.25–25mg/kg). It also produced a significant and dose-dependent motor coordination deficit in mice at the doses tested (P<0.01). The intraperitoneal median lethal dose in mice was 774.6mg/kg while the preliminary phytochemical screening revealed the presence of alkaloids, tannins, saponins and flavonoids. These results suggest that methanolic root bark extract of S. virosa contains biologically active principles that are sedative in nature and lend pharmacological credence to the ethnomedical use of the plant.  相似文献   
38.
Background Many therapeutic modalities have been suggested for treatment of the chronic hand eczema. Despite good immediate efficacy of some of these treatments, there is high recurrence of the dermatitis following cessation of the treatment. Aim Regarding the beneficial effects of the zinc sulfate on the skin, we designed a double blind study to evaluate the efficacy of the ‘0.05% Clobetasol + 2.5% zinc sulphate’ cream versus ‘0.05% Clobetasol alone’ cream in the treatment of the chronic hand eczema. Subjects and Methods This study was a double‐blind, right to left, prospective, clinical trial. In total, 47 patients with chronic hand eczema admitted to dermatology center of Isfahan University of Medical Sciences were selected and their right hand or left hand were selected at random to be treated with either the ‘0.05% Clobetasol + 2.5% zinc sulphate’ cream or ‘0.05% Clobetasol alone’ cream twice daily for 2 weeks. All of the patients were treated for 2 weeks and were followed up at weeks 2, 4, 6 and 8 after starting the treatment. For determining the severity of chronic hand eczema, we assessed and scored 4 different characteristics of the lesions including redness; scaling; lichenification and pruritus. The data were analyzed using SPSS program (release 13) and statistical tests including Mann‐Whitney test. Results Overall, 47 patients (94 samples) were evaluated. All of these patients had similar and symmetrical lesions on their right and left hands. Out of them, 35 patients were females and 12 patients were male. In all of the evaluated characterisitics, the ‘0.05% Clobetasol + 2.5% zinc sulphate’ cream was more effective than ‘0.05% Clobetasol alone’ cream (P < 0.05). The recurrence rate of eczema was significantly lower in the group treated with this combination treatment (P < 0.05). Conclusion With regard to the encouraging results of the combination treatment with Clobetasol + zinc sulphate, we suggest that in a more extensive clinical trial, the efficacy of this treatment against chronic hand dermatitis be evaluated. In addition, evaluation of this combination therapy against other inflammatory dermatosis seems to be logical.  相似文献   
39.
40.
Smith  TP; Cragg  AH; Berbaum  KS 《Radiology》1989,170(3):941
  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