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   341篇
  免费   14篇
  国内免费   16篇
耳鼻咽喉   4篇
儿科学   70篇
妇产科学   16篇
基础医学   56篇
临床医学   27篇
内科学   84篇
皮肤病学   2篇
神经病学   8篇
特种医学   3篇
外科学   13篇
综合类   1篇
预防医学   41篇
眼科学   1篇
药学   37篇
肿瘤学   8篇
  2022年   2篇
  2021年   3篇
  2020年   7篇
  2019年   7篇
  2018年   10篇
  2017年   8篇
  2016年   18篇
  2015年   15篇
  2014年   11篇
  2013年   28篇
  2012年   27篇
  2011年   30篇
  2010年   11篇
  2009年   5篇
  2008年   14篇
  2007年   16篇
  2006年   10篇
  2005年   11篇
  2004年   13篇
  2003年   9篇
  2002年   11篇
  2001年   14篇
  2000年   9篇
  1999年   10篇
  1998年   3篇
  1996年   2篇
  1995年   2篇
  1994年   3篇
  1992年   5篇
  1991年   8篇
  1990年   3篇
  1989年   3篇
  1988年   3篇
  1987年   4篇
  1986年   6篇
  1985年   1篇
  1984年   2篇
  1983年   2篇
  1982年   1篇
  1981年   1篇
  1979年   2篇
  1977年   1篇
  1975年   1篇
  1973年   4篇
  1972年   1篇
  1971年   2篇
  1969年   6篇
  1968年   1篇
  1967年   2篇
  1966年   2篇
排序方式: 共有371条查询结果,搜索用时 15 毫秒
1.
2.
3.
OBJECTIVE: A prospective, multicentre study was conducted to evaluate the burden of laboratory confirmed influenza in healthy children and their household contacts. METHODS: The patients were enrolled in four emergency departments (EDs) and by five primary care paediatricians (PCPs) in different Italian municipalities 2 days a week between November 1, 2001 and April 30, 2002. The study involved 3771 children less than 14 years of age with no chronic medical conditions who presented with a respiratory tract infection in EDs or PCP outpatient clinics during the study period. Nasopharyngeal swabs were collected for the isolation of influenza viruses and RNA detection. Information was also collected concerning respiratory illnesses and related morbidities among the study children and their household contacts. RESULTS: Influenza virus was demonstrated in 352 cases (9.3%). In comparison with the influenza negative children, those who were influenza positive had an older mean age, were more often attending day care centres or schools, more frequently experienced fever and croup, received more antipyretics, and had a longer duration of fever and school absence. Furthermore, their parents and siblings had more respiratory illnesses, received more antipyretics and antibiotics, needed more medical visits, missed more work or school days, and needed help at home to care for the ill children for a longer period of time. CONCLUSIONS: Influenza has a significant clinical and socioeconomic impact on healthy children and their families. Prevention strategies should also focus on healthy children regardless of their age because of their role in disease transmission.  相似文献   
4.
In the last 20 years, gut microbiota in patients with cystic fibrosis (CF) has become an object of interest. It was shown that these patients had gut dysbiosis and this could explain not only the intestinal manifestations of the disease but also part of those involving the respiratory tract. The acquisition of previously unknown information about the importance of some bacteria, i.e., those partially or totally disappeared in the gut of CF patients, in the regulation of the activity and function of the gut and the lung was the base to suggest the use of probiotics in CF patients. The main aim of this paper is to discuss the biological basis for probiotic administration to CF patients and which results could be expected. Literature analysis showed that CF intestinal dysbiosis depends on the same genetic mutations that condition the clinical picture of the diseases and is aggravated by a series of therapeutic interventions, such as dietary modifications, the use of antibiotics, and the administration of antacids. All this translates into a significant worsening of the structure and function of organs, including the lung and intestine, already deeply penalized by the genetic alterations of CF. Probiotics can intervene on dysbiosis, reducing the negative effects derived from it. However, the available data cannot be considered sufficient to indicate that these bacteria are essential elements of CF therapy. Further studies that take into account the still unsolved aspects on how to use probiotics are absolutely necessary.  相似文献   
5.
6.
Introduction: Patients with end-stage renal disease (ESRD) are considered at higher risk of influenza-related complications and are listed worldwide among the subjects for whom yearly influenza vaccination is strongly recommended. However, influenza vaccination coverage of patients with ESRD is significantly lower than desired.

Areas covered: This paper explores why compliance with official recommendations for influenza vaccination is poor in patients with ESRD and analyzes the true risk of infection as well as the immunogenicity, the effectiveness and the safety of influenza vaccination in these patients.

Expert opinion: Epidemiological and clinical data support the importance of influenza in conditioning clinical deterioration of patients with ESRD, particularly in relation to their level of immunosuppression. However, the variable levels of immunodeficiency detected in patients with ESRD may reduce the immune response to influenza vaccination, which appears to be lower than that usually found in healthy subjects. However, few studies are available, and they are difficult to compare for several reasons. Additionally, limited data have been collected on influenza vaccine effectiveness, although the available studies support positive results of vaccination on outcomes of severe disease. Despite such limitations, it is important to highlight that all the available studies have confirmed the good safety and tolerability of inactivated influenza vaccines. These findings, together with the risks associated with influenza in these patients, support annual influenza vaccination in patients with ESRD as well as vaccination of their close contacts and should be presented in educational programs organized for nephrologists and patient associations.  相似文献   

7.
BACKGROUND: A pivotal role of oestrogen receptor-beta has been suggested in colon carcinogenesis in humans. However, few data are available on oestrogen receptor-beta in colorectal pre-cancerous lesions. AIM: In the present study, we evaluated oestrogen receptor-beta expression and its possible correlation with proliferative activity and apoptosis in colorectal adenomas and normal colon tissue. PATIENTS/METHODS: Adenomatous tissue from 25 patients with colonic polyps, and normal tissue from 25 controls were used. Oestrogen receptor-beta expression, colonocyte proliferation (expressed as PCNA positivity) and apoptosis were evaluated. RESULTS: In adenomatous tissue, a significant reduction of oestrogen receptor-beta was observed compared to normal mucosa (10.1+/-5.5% vs. 44.2+/-13.7; p<0.03), while the expression of oestrogen receptor-alpha remained unvaried. Cell proliferative activity significantly increased in adenomatous tissue compared to normal mucosa (59.3+/-7.1 vs. 18.5+/-8.8; p<0.0001), doubling the PCNA/apoptosis ratio. An inverse correlation was found between oestrogen receptor-beta and PCNA expression in adenomas (r=-0.81), a datum confirmed by confocal microscopy evaluation. CONCLUSIONS: Our data demonstrate, for the first time, a significant reduction of oestrogen receptor-beta expression already in the pre-cancerous phase of colon carcinogenesis. This suggests a role of selective oestrogen receptor-beta agonists in the prevention of colorectal cancer.  相似文献   
8.
Tumor necrosis factor alpha (TNFα) in intestinal mucosa plays a key role in the inflammation characterizing Crohn’s disease (CD). Moreover, adhesion molecule syndecan-1 mediates the maintenance of mucosal integrity and supports tissue repair. Therefore, our aim in this study was to correlate simultaneous expression of TNFα and syndecan-1 in patients affected by CD. Biopsies from 10 patients with CD of large bowel and 10 subjects with irritable bowel syndrome (controls) were studied by immunohistochemical detection of both TNFα and syndecan-1 on successive serial sections. Overall labeling index (OLI) was indicated by the percentage of positive stromal (i.e., nonepithelial) cells/1000 counted in randomized fields, whereas selected labeling index (SLI) was represented by the simultaneous evaluation of both molecules in a same single selected field of each specimen. TNFα and syndecan-1 OLI were significantly higher in CD compared with controls, while SLI showed an inverse relationship between the molecules in CD which was not observed in controls. Epithelial syndecan-1 cytoplasmatic staining of superficial epithelium was associated with loss of basolateral staining in the crypts and high stromal TNFα in CD. In conclusion, TNFα and syndecan-1 expression is increased in the intestinal mucosa of patients with CD. However, the expression of the two molecules is inversely related when a single field is considered, these data supporting the possibility of a downregulation exerted by TNFα.  相似文献   
9.
Millions of people throughout the world are bitten by animals each year. About 90 % of the bites are caused by dogs and cats, and infections are the most common complications. As children are the most frequently bitten subjects, pediatricians should provide parents with everything they need to know in order to confront the problem. However, this does not seem to be case and, as the treatment of bite wounds is frequently inappropriate and delayed, the risk of acute infection and sequelae is increased. The main aim of this review is to discuss the epidemiology, microbiology, and clinical characteristics of infections due to dog and cat bites in children, and suggest the best approach to their management. Analysis of the published literature shows that prompt treatment is necessary in order to reduce the risk of infection. The therapeutic measures include wound washing, specific prophylaxis (i.e., tetanus and/or rabies), and antibiotics in the case of immunocompromised patients or deep wounds (particularly if there is evidence of edema or crushing), facial bites, or any wound over a tendon or bone.  相似文献   
10.
Intestinal microbiota is a “dynamic organ” influencing host metabolism, nutrition, physiology and immune system. Among its several interactions, the role of a phosphatidylcholine metabolite derived by gut flora activity, i.e., trimethylamine-N-oxide (TMAO), allows perceiving a novel insight in the cardiovascular risk scenario, being a strong predictor of this condition. Based on current reports, including the paper of Tang et al., we describe here: the possible role of intestinal microbiota in cardiovascular risk as well as potential interventions to reduce gut flora TMAO production by diet, probiotics and antibiotics. Finally, we highlight the possibility of evaluating, monitoring and modulating TMAO in order to use its serum levels as a marker of cardiovascular risk in the next future, when the need of controlled studies on large series will be satisfied.  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