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   1696篇
  免费   129篇
  国内免费   159篇
耳鼻咽喉   15篇
儿科学   50篇
妇产科学   54篇
基础医学   190篇
口腔科学   29篇
临床医学   221篇
内科学   306篇
皮肤病学   16篇
神经病学   197篇
特种医学   33篇
外科学   332篇
综合类   19篇
一般理论   2篇
预防医学   282篇
眼科学   7篇
药学   81篇
肿瘤学   150篇
  2023年   12篇
  2022年   21篇
  2021年   64篇
  2020年   40篇
  2019年   69篇
  2018年   55篇
  2017年   28篇
  2016年   55篇
  2015年   55篇
  2014年   80篇
  2013年   85篇
  2012年   141篇
  2011年   141篇
  2010年   70篇
  2009年   67篇
  2008年   101篇
  2007年   132篇
  2006年   103篇
  2005年   101篇
  2004年   107篇
  2003年   91篇
  2002年   97篇
  2001年   50篇
  2000年   43篇
  1999年   33篇
  1998年   27篇
  1997年   17篇
  1996年   4篇
  1995年   11篇
  1994年   6篇
  1993年   4篇
  1992年   5篇
  1991年   2篇
  1990年   2篇
  1989年   3篇
  1988年   5篇
  1987年   2篇
  1986年   3篇
  1985年   9篇
  1984年   5篇
  1983年   7篇
  1982年   4篇
  1981年   6篇
  1980年   2篇
  1979年   3篇
  1977年   5篇
  1975年   2篇
  1961年   1篇
  1945年   1篇
  1932年   1篇
排序方式: 共有1984条查询结果,搜索用时 31 毫秒
31.
In a cross-sectional study of 641 Schistosoma japonicum-infected individuals in Leyte, Philippines, who were 7-30 years old, we determined the grade of hepatic fibrosis (HF) by ultrasound and used anthropometric measurements and hemoglobin levels to assess nutritional status. Serum levels of interleukin (IL)-1, IL-6, and IL-10; tumor-necrosis factor (TNF)-alpha; soluble TNF- alpha receptor I; and C-reactive protein (CRP) were measured to examine the association between these markers of inflammation and HF grade. HF was present in 8.9% of the cohort; the majority of cases were mild (grade I), and severe (grade II or grade III) cases occurred only in male individuals. Compared with individuals without HF, those with severe HF--and, to a lesser degree, those with mild HF--had a significantly lower body-mass index (BMI) and BMI z-score, a higher prevalence of anemia, and a higher level of CRP and were more likely to produce IL-6; furthermore, those with severe HF had a significantly higher level of IL-1, compared with those either without HF or with mild HF. These findings suggest that even mild HF is associated with nutritional morbidity and underscore the importance of early recognition and treatment. In addition, our data are consistent with the hypothesis that, by systemically increasing the levels of the proinflammatory cytokines IL-1 and IL-6, HF causes undernutrition and anemia.  相似文献   
32.
33.
34.
BACKGROUND: Delirium and pain are common following hip fracture. Untreated pain has been shown to increase the risk of delirium in older adults undergoing elective surgery. This study was performed to examine the relationship among pain, analgesics, and other factors on delirium in hip fracture patients. METHODS: We conducted a prospective cohort study at four New York hospitals that enrolled 541 patients with hip fracture and without delirium. Delirium was identified prospectively by patient interview supplemented by medical record review. Multiple logistic regression was used to identify risk factors. RESULTS: Eighty-seven of 541 patients (16%) became delirious. Among all subjects, risk factors for delirium were cognitive impairment (relative risk, or RR, 3.6; 95% confidence interval, or CI, 1.8-7.2), abnormal blood pressure (RR 2.3, 95% CI 1.2-4.7), and heart failure (RR 2.9, 95% CI 1.6-5.3). Patients who received less than 10 mg of parenteral morphine sulfate equivalents per day were more likely to develop delirium than patients who received more analgesia (RR 5.4, 95% CI 2.4-12.3). Patients who received meperidine were at increased risk of developing delirium as compared with patients who received other opioid analgesics (RR 2.4, 95% CI 1.3-4.5). In cognitively intact patients, severe pain significantly increased the risk of delirium (RR 9.0, 95% CI 1.8-45.2). CONCLUSIONS: Using admission data, clinicians can identify patients at high risk for delirium following hip fracture. Avoiding opioids or using very low doses of opioids increased the risk of delirium. Cognitively intact patients with undertreated pain were nine times more likely to develop delirium than patients whose pain was adequately treated. Undertreated pain and inadequate analgesia appear to be risk factors for delirium in frail older adults.  相似文献   
35.

Objective

To identify important sources of distress among burn survivors at discharge and 6, 12, and 24 months postinjury, and to examine if the distress related to these sources changed over time.

Design

Exploratory.

Setting

Outpatient burn clinics in 4 sites across the country.

Participants

Participants who met preestablished criteria for having a major burn injury (N=1009) were enrolled in this multisite study.

Interventions

Participants were given a previously developed list of 12 sources of distress among burn survivors and asked to rate on a 10-point Likert-type scale (0=no distress to 10=high distress) how much distress each of the 12 issues was causing them at the time of each follow-up.

Main Outcomes Measures

The Medical Outcomes Study 12-Item Short-Form Health Survey was administered at each time point as a measure of health-related quality of life. The Satisfaction With Appearance Scale was used to understand the relation between sources of distress and body image. Finally, whether a person returned to work was used to determine the effect of sources of distress on returning to employment.

Results

It was encouraging that no symptoms were worsening at 2 years. However, financial concerns and long recovery time are 2 of the highest means at all time points. Pain and sleep disturbance had the biggest effect on ability to return to work.

Conclusions

These findings can be used to inform burn-specific interventions and to give survivors an understanding of the temporal trajectory for various causes of distress. In particular, it appears that interventions targeted at sleep disturbance and high pain levels can potentially effect distress over financial concerns by allowing a person to return to work more quickly.  相似文献   
36.
37.
38.
39.
40.
OBJECTIVES: To examine the relationship between early physical therapy (PT), later therapy, and mobility 2 and 6 months after hip fracture. DESIGN: Prospective, multisite observational study. SETTING: Four hospitals in the New York City area. PARTICIPANTS: Four hundred forty-three hospitalized older patients discharged after surgery for hip fracture in 1997-98. MEASUREMENTS: Patient demographics, fracture type, comorbidities, dementia, number of new impairments at discharge, amount of PT between day of surgery and postoperative day (POD) 3, amount of therapy between POD4 and 8 weeks later, and prefracture, 2-, and 6-month mobility measured using the Functional Independence Measure. RESULTS: More PT immediately after hip fracture surgery was associated with significantly better locomotion 2 months later. Each additional session from the day of surgery through POD3 was associated with an increase of 0.4 points (P=.032) on the 14-point locomotion scale, but the positive relationship between early PT and mobility was attenuated by 6 months postfracture. There was no association between later therapy and 2- or 6-month mobility. CONCLUSION: PT immediately after hip fracture surgery is beneficial. The effects of later therapy on mobility were difficult to assess because of limitations of the data. Well-designed randomized, controlled trials of the effect of varying schedules and amounts of therapy on functional status after hip fracture would be informative.  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