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   2250篇
  免费   101篇
  国内免费   13篇
耳鼻咽喉   47篇
儿科学   198篇
妇产科学   89篇
基础医学   179篇
口腔科学   176篇
临床医学   190篇
内科学   338篇
皮肤病学   106篇
神经病学   216篇
特种医学   60篇
外科学   378篇
综合类   32篇
预防医学   93篇
眼科学   63篇
药学   126篇
中国医学   3篇
肿瘤学   70篇
  2024年   1篇
  2023年   15篇
  2022年   20篇
  2021年   48篇
  2020年   41篇
  2019年   51篇
  2018年   53篇
  2017年   46篇
  2016年   88篇
  2015年   72篇
  2014年   120篇
  2013年   115篇
  2012年   184篇
  2011年   180篇
  2010年   107篇
  2009年   82篇
  2008年   143篇
  2007年   159篇
  2006年   170篇
  2005年   160篇
  2004年   126篇
  2003年   94篇
  2002年   81篇
  2001年   42篇
  2000年   36篇
  1999年   33篇
  1998年   15篇
  1997年   19篇
  1996年   7篇
  1995年   4篇
  1994年   5篇
  1993年   4篇
  1992年   2篇
  1991年   7篇
  1990年   6篇
  1989年   7篇
  1988年   5篇
  1987年   1篇
  1986年   6篇
  1985年   5篇
  1976年   2篇
  1975年   1篇
  1970年   1篇
排序方式: 共有2364条查询结果,搜索用时 15 毫秒
1.
Abstract

We have investigated communication preferences of mammography results in 90 patients through a structured interview approach. About 81% of patients expressed that they wanted to get the results, and 18% expressed that getting the results does not help if they are incomprehensible. In patients who want to get the results, 80% preferred face-to-face interaction with physicians, whereas the others preferred other modes of communication to prevent loss of time. Majority of patients infavor of face-to-face interaction (57%) preferred both the referring physician and the radiologist. Comprehensibility and fast delivery of reports, plus direct communication with radiologists are the requirements in mammography patients while implementing patient-centered radiology.  相似文献   
2.
Dermatophytid reactions are secondary eruptions in response to dermatophytosis. Only a few cases demonstrating an association between dermatophytid reactions and tinea capitis have been reported. Dermatophytid reactions were evaluated in patients diagnosed with kerion celsi. Patients admitted to the dermatology clinic of Van Regional Training and Research Hospital between November 22, 2012, and July 1, 2013, diagnosed with kerion celsi were evaluated for dermatophytid reactions. Six girls (32%) and 13 boys (68%) were included in this study. Dermatophytid reactions were detected in 13 of the 19 patients (68%). Seven patients (36.84%) had eczematous patches or plaques and three (15.8%) had papules. Eczematous lesions, papules, and pustules were noted in two patients (10.5%) and one (5.3%) had signs of an angioedema‐like reaction. Dermatophytid reactions in all patients were observed before the initiation of therapy. According to our clinical experiences, dermatophytid reactions in patients with kerion celsi were more common than reported. Eczematous scaly patches or plaques were the most frequently seen forms of dermatophytid in patients with kerion celsi. Dermatophytid reactions may occur before or after initiation of systemic antifungal therapy. Recognition of this reaction is important so that dermatophytids can be distinguished from drug reactions and the decision can be made whether to continue or to stop the systemic antifungal treatment.  相似文献   
3.
OBJECTIVE: To evaluate the possible effects of sex and age on strength-duration time constant (SDTC). METHODS: The SDTC of 126 healthy volunteers was measured following stimulation of right median nerve at the wrist. Variations in values were evaluated according to sex and age. RESULTS: The SDTC was 438.6+/-114.5 micros in women and 396.2+/-90.3 in men (P=.023). In men, as age increased, so did SDTC. However, this was not true in women. Comparing the values of women and men, aged below 40, demonstrated a difference in excitability, confined to younger patients. CONCLUSIONS: As SDTC depends on the biophysical properties of the axonal membrane and can provide some information about Na(+) channel function, these data raise the possibility of a difference in Na(+) channel function between men and women and a difference in the conductance with age. SIGNIFICANCE: The age- and sex-related differences shown in this study suggest a possible biochemical or hormonal influence on axonal excitability.  相似文献   
4.
5.
There is a large body of literature describing the causative role of oxidative stress mediated by increased levels of reactive oxygen species in the pathogenesis of cardiovascular disease such as atherosclerosis, hypertension, and restenosis after angioplasty. The positioning of a soft silicone collar around the rabbit carotid artery elicits intimal thickening. The findings from recent studies demonstrated that both intimal thickening and atherosclerosis lead to synthesis of inducible nitric oxide synthase, resulting in abundant amounts of nitric oxide. We investigated the effects of collaring and nicardipine treatment on the activities of antioxidant enzymes, superoxide dismutase and catalase, and total nitrite/nitrate levels, stable products of nitric oxide. Placing the collar increased the total nitrite/ nitrate levels and decreased superoxide dismutase activity in collared arteries. Treatment with nicardipine (20 mg/kg/day, s.c.) prevented enhanced nitric oxide degradation without affecting superoxide dismutase and catalase activities. Our results suggest that enhanced nitric oxide production and superoxide anion are generated in response to the collaring, resulting in oxidative stress within the segment in this model.  相似文献   
6.
OBJECTIVE: Hyperventilation and ischaemia increase axonal excitability by changing Na+ conductance in healthy subjects. However, the changes in excitability during and after ischaemia in diabetic patients are less than in healthy controls. This is known as ischaemic resistance. In this study, we investigated the effects of hyperventilation for 20 min on strength-duration time constant (SDTC) of motor axons of the median nerve of diabetic patients with polyneuropathy to determine whether diabetics are less affected by hyperventilation, a form of resistance similar to the ischaemic resistance of diabetics. METHODS: The SDTC of 14 diabetic patients with polyneuropathy and 10 healthy volunteers were measured following stimulation of right median nerve at the wrist prior to and after hyperventilation for 20 min. RESULTS: There was a significant increase in the SDTC in control subjects, but no significant change in the SDTC for patients with diabetic polyneuropathy. The score of the clinical response (paraesthesiae and carpopedal spasm) to hyperventilation of controls was also significantly greater in the controls than the patients. CONCLUSION: Hyperventilation for 20 min has little influence on SDTC in patients with diabetic polyneuropathy. SIGNIFICANCE: The 'resistance' of diabetic nerve is not confined to ischaemia but involves other manoeuvres that can alter axonal excitability.  相似文献   
7.
OBJECTIVES: Deep hypothermic circulatory arrest (DHCA) is commonly used during thoracic aortic surgery, and is initiated only after a sufficient degree of cerebral hypothermia is induced. The criteria for initiating DHCA vary among institutions: most centers use temperature criteria, some use electroencephalography, and a minority use jugular bulb oxyhemoglobin saturation SjO(2) criteria. The purpose of this study was to determine whether the use of SjO(2) monitoring to guide the onset of DHCA was associated with better post-operative neuropsychological outcome. METHODS: Sixty-one thoracic aortic surgical patients underwent both pre- and post-operative neuropsychological testing. Patients were divided into three groups: (1) those with SjO(2)> or =95% at DHCA onset; (2) those with SjO(2)<95% at DHCA onset; and (3) those without SjO(2) monitoring. RESULTS: There were no statistically significant differences in the incidence of post-operative decline in neuropsychological function among the three groups of patients. Patients in whom SjO(2) data were used to guide onset of DHCA had lower esophageal and bladder temperatures at that time compared with patients without SjO(2) monitoring. CONCLUSIONS: Monitoring of SjO(2) had no apparent effect upon post-operative neuropsychological outcome, and there were no trends in our small patient cohort suggesting differences that our study was not adequately powered to detect. Use of SjO(2) monitoring was associated with more profound hypothermia prior to DHCA due to more prolonged cooling in attempts to bring the SjO(2) above the 95% threshold. Using our institutional cooling protocol, SjO(2) monitoring does not appear to increase neuroprotection in patients undergoing DHCA for thoracic aortic repairs.  相似文献   
8.
9.
10.
Discontinuation of medication is the treatment of choice for patients with chronic daily headache (CDH) who overuse their medications. This treatment may be difficult due to increased headache severity observed in patients immediately after withdrawal. We retrospectively evaluated the efficacy of valproic acid therapy in 66 patients with overuse of CDH medication during withdrawal therapy. Patients were all withdrawn from medications and valproic acid started at 250 mg or 500 mg daily. Forty-two (63.6%) patients had decreased headache severity, including 27.3% objective responses in the first week. At the last visit in the 12th week, 50 patients were headache-free and only one patient had persistent headache. Fifteen patients withdrew from therapy due to side effects and lost to follow-up within this timeframe. Thus, low dose valproic acid appears to be safe and effective in the management of withdrawal therapy.  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