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   802篇
  免费   67篇
  国内免费   2篇
耳鼻咽喉   2篇
儿科学   17篇
妇产科学   3篇
基础医学   102篇
口腔科学   6篇
临床医学   67篇
内科学   205篇
皮肤病学   11篇
神经病学   54篇
特种医学   13篇
外科学   60篇
综合类   11篇
现状与发展   1篇
预防医学   135篇
药学   130篇
中国医学   5篇
肿瘤学   49篇
  2024年   2篇
  2023年   6篇
  2022年   22篇
  2021年   40篇
  2020年   18篇
  2019年   33篇
  2018年   37篇
  2017年   26篇
  2016年   21篇
  2015年   31篇
  2014年   33篇
  2013年   30篇
  2012年   66篇
  2011年   64篇
  2010年   31篇
  2009年   28篇
  2008年   50篇
  2007年   39篇
  2006年   46篇
  2005年   51篇
  2004年   40篇
  2003年   37篇
  2002年   19篇
  2001年   13篇
  2000年   15篇
  1999年   10篇
  1998年   13篇
  1997年   5篇
  1996年   3篇
  1995年   4篇
  1994年   2篇
  1993年   6篇
  1992年   8篇
  1991年   3篇
  1990年   1篇
  1989年   5篇
  1987年   2篇
  1986年   2篇
  1985年   1篇
  1984年   2篇
  1981年   1篇
  1977年   1篇
  1975年   1篇
  1942年   1篇
  1937年   2篇
排序方式: 共有871条查询结果,搜索用时 15 毫秒
71.
72.
Lipoid proteinosis is a rare hereditary disease which often results in bilateral calcifications in the medial temporal region. Thirty-four adults living with lipoid proteinosis (>10% of the world population) were extensively assessed with standardized neuropsychiatric and neuropsychological measures. Of these, 27 patients representing a homogenous group living in the Northern Cape were matched with 47 controls. Subjects with lipoid proteinosis had a high incidence of neuropsychiatric disorders and performed poorly on facial recognition of positive and negative emotions and on many neuropsychological measures. These findings are consistent with involvement of the medial temporal areas in cognitive and emotive processing.  相似文献   
73.

Background

Dialysis patients are confronted with numerous, complex problems, which make it difficult to identify individual patient's most prominent problems. The objectives of this study were to (1) identify dialysis patients' most prominent problems from a patient perspective and (2) to calculate disease-specific norms for questionnaires measuring these problems.

Methods

One hundred seventy-five patients treated with hemodialysis or peritoneal dialysis completed a priority list on several domains of functioning (e.g., physical health, mental health, social functioning, and daily activities) and a set of matching questionnaires assessing patient functioning on these domains. Patient priorities were assessed by calculating the importance ranking of each domain on the priority list. Subsequently, disease-specific norm scores were calculated for all questionnaires, both for the overall sample and stratified by patient characteristics.

Results

Fatigue was listed as patients' most prominent problem. Priorities differed between male and female patients, younger and older patients, and home and center dialysis patients, which was also reflected in their scores on the corresponding domains of functioning. Therefore, next to general norm scores, we calculated corrections to the general norms to take account of patient characteristics (i.e., sex, age, and dialysis type).

Conclusions

Results highlight the importance of having attention for the specific priorities and needs of each individual patient. Adequate disease-specific, norm-based assessment is not only necessary for diagnostic procedures but is an essential element of patient-centered care: It will help to better understand and respect individual patient needs and tailor treatment accordingly.  相似文献   
74.
Acknowledgments     
Sexual Abuse: A Journal of Research and Treatment -  相似文献   
75.
The single gene mutation tau in the Syrian hamster—apart from its effect on the circadian organization of locomotor activity—has a pronounced influence on body weight. In this study we investigate the impact of maternal and pup genotypes at the tau-locus on the growth rate of pups. Homozygous tau mutant hamsters (circadian period of 20 hours) had lower growth rates and adult body weights than wild-type hamsters, whereas heterozygous tau mutants (circadian period of 22 hours) were intermediate. In addition, heterozygous pups from heterozygous dams grew heavier than those from wild-type and homozygous dams. The effect of maternal genotype was further evaluated in a cross-foster design, where wild-type and homozygous mutant pups were fostered at birth to either wild-type or homozygous mutant dams. At all ages, the maternal tau genotype had a negative effect on body weight, whereas the pup tau genotype had a positive effect during the preweaning period and a negative effect afterward.  相似文献   
76.
77.
Food-based dietary guidelines (FBDG) have primarily been designed for the consumer to encourage healthy, habitual food choices, decrease chronic disease risk and improve public health. However, minimal research has been conducted to evaluate whether FBDG are utilised by the public. The present review used a framework of three concepts, awareness, understanding and use, to summarise consumer evidence related to national FBDG and food guides. Searches of nine electronic databases, reference lists and Internet grey literature elicited 939 articles. Predetermined exclusion criteria selected twenty-eight studies for review. These consisted of qualitative, quantitative and mixed study designs, non-clinical participants, related to official FBDG for the general public, and involved measures of consumer awareness, understanding or use of FBDG. The three concepts of awareness, understanding and use were often discussed interchangeably. Nevertheless, a greater amount of evidence for consumer awareness and understanding was reported than consumer use of FBDG. The twenty-eight studies varied in terms of aim, design and method. Study quality also varied with raw qualitative data, and quantitative method details were often omitted. Thus, the reliability and validity of these review findings may be limited. Further research is required to evaluate the efficacy of FBDG as a public health promotion tool. If the purpose of FBDG is to evoke consumer behaviour change, then the framework of consumer awareness, understanding and use of FBDG may be useful to categorise consumer behaviour studies and complement the dietary survey and health outcome data in the process of FBDG evaluation and revision.  相似文献   
78.
BACKGROUND: Filamentous haemagglutinin (FHA) of Bordetella pertussis subverts host immune responses by inhibiting interleukin (IL)12 and enhancing IL10 production by macrophages and dendritic cells, and promoting the induction of regulatory T cells. Hypothesis: Injection of FHA would ameliorate disease in a T cell-dependent model of colitis via the induction of anti-inflammatory cytokines and regulatory T cells. METHODS: Colitis was induced by injection of CD4CD45RB(high) naive T cells into severe combined immunodeficient (SCID) mice. Mice were treated with four subcutaneous injections of FHA or buffer alone. RESULTS: Parenteral injection of FHA stimulated IL10 and/or transforming growth factor beta production in local and mesenteric lymph nodes and Peyer's patches of mice 2-6 h after administration. Compared with phosphate-buffered saline-treated mice, FHA-treated SCID mice had significantly (p<0.01) less weight loss, lower colon weight, less colon shrinkage and reduced inflammatory lesions. The therapeutic effect of FHA was associated with enhanced IL10 and reduced type 1 and type 2 T helper cytokine production by spleen cells. Finally, FHA also attenuated the symptoms of colitis in SCID mice transferred with CD4CD45RB(high) T cells from IL10-deficient mice. CONCLUSIONS: Our finding shows that FHA suppresses type 1 T helper and pro-inflammatory cytokines, and ameliorates disease activity in a chronic T cell-dependent model of colitis, an effect that was not dependent on IL10 production by T cells, but was associated with induction of anti-inflammatory cytokines in vivo. Having already been used as a pertussis vaccine component in children, FHA is a promising candidate for clinical testing in patients with Crohn's disease.  相似文献   
79.

Background and objectives

Kidney function gradually decreases with age, and myocardial infarction accelerates this deterioration. Omega-3 (n-3) fatty acids may slow down the decline of kidney function. The effect of marine and plant-derived n-3 fatty acids on kidney function in patients after myocardial infarction was examined.

Design, setting, participants, & measurements

In the Alpha Omega Trial, 2344 patients with history of myocardial infarction ages 60–80 years old (81% men) were randomized to one of four trial margarines. The patients received an additional targeted amount of 400 mg/d eicosapentaenoic acid and docosahexaenoic acid, 2 g/d α-linolenic acid, eicosapentaenoic acid–docosahexaenoic acid plus α-linolenic acid, or placebo for 40 months. Serum cystatin C and serum creatinine were assessed at baseline and after 40 months. Creatinine–cystatin C-based GFR was estimated with the Chronic Kidney Disease Epidemiology Collaboration equation.

Results

Patients consumed 19.9 g margarine/d, providing an additional 239 mg/d eicosapentaenoic acid with 159 mg/d docosahexaenoic acid, 1.99 g/d α-linolenic acid, or both in the active treatment groups. After 40 months, compared with baseline, mean (±SD) creatinine–cystatin C-based GFR was −6.9 (±12.6), −4.8 (±13.4), −6.2 (±12.8), and −6.0 (±13.0) ml/min per 1.73 m2 in the placebo, eicosapentaenoic acid–docosahexaenoic acid, α-linolenic acid, and eicosapentaenoic acid–docosahexaenoic acid plus α-linolenic acid groups, respectively. After 40 months, in patients receiving eicosapentaenoic acid–docosahexaenoic acid compared with placebo, the decline in creatinine–cystatin C-based GFR was 2.1 less (95% confidence interval, 0.6 to 3.6; P<0.01) ml/min per 1.73 m2; other comparisons were not statistical significant. Odds ratios (95% confidence intervals) of incident CKD (<60 ml/min per 1.73 m2) and rapid decline of kidney function (≥3 ml/min per year) for eicosapentaenoic acid–docosahexaenoic acid compared with placebo were 0.83 (0.58 to 1.18) and 0.85 (0.67 to 1.08), respectively.

Conclusions

Long-term supplementation with 400 mg/d eicosapentaenoic acid–docosahexaenoic acid provides a small beneficial effect on kidney function in patients with a history of myocardial infarction.  相似文献   
80.
PURPOSE: To investigate the relationship between duration and intensity of physical activity and disability 10 years later, and to investigate the possible effect of selective mortality. METHOD: Longitudinal data of 560 men aged 70?-?89 years, without disability at baseline from the Finland, Italy and The Netherlands Elderly (FINE) Study was used. Physical activity in 1990 was based on activities like walking, bicycling and gardening. Disability severity (three categories) in 1990 and 2000 was based on instrumental activities, mobility and basic activities of daily living. RESULTS: Men in the highest tertile of total physical activity had a lower risk of disability than men in the lowest tertile (odds ratio (OR) 0.46; 95% confidence interval (CI): 0.26-0.84). This was due to duration of physical activity (OR highest tertile 0.42; 95% CI: 0.23-0.78 compared to the lowest tertile). Intensity of physical activity was not associated with disability. Addition of deceased men as fourth category leaded to weaker associations between physical activity and disability (OR highest tertile 0.67; 95% CI: 0.44-1.02). CONCLUSIONS: Even in old age among relatively healthy men, a physically active lifestyle was inversely related to disability. To prevent disability duration of physical activity seems to be more important than intensity.  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