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   250篇
  免费   24篇
儿科学   4篇
妇产科学   3篇
基础医学   26篇
口腔科学   12篇
临床医学   47篇
内科学   45篇
神经病学   9篇
特种医学   6篇
外科学   28篇
综合类   5篇
预防医学   26篇
眼科学   27篇
药学   23篇
中国医学   5篇
肿瘤学   8篇
  2023年   5篇
  2022年   15篇
  2021年   11篇
  2020年   11篇
  2019年   13篇
  2018年   16篇
  2017年   16篇
  2016年   17篇
  2015年   9篇
  2014年   18篇
  2013年   12篇
  2012年   33篇
  2011年   26篇
  2010年   12篇
  2009年   11篇
  2008年   9篇
  2007年   13篇
  2006年   4篇
  2005年   7篇
  2004年   1篇
  2003年   3篇
  2002年   2篇
  2000年   2篇
  1999年   2篇
  1997年   1篇
  1996年   1篇
  1995年   1篇
  1981年   2篇
  1979年   1篇
排序方式: 共有274条查询结果,搜索用时 15 毫秒
21.
22.
Direct current cardioversion, which produces electrical energy, is highly effective for the termination of cardiac arrhythmia and sometimes is indicated in patients with coronary artery stents due to arrhythmias. Only a few reports have been published describing the potential adverse interactions between foreign bodies and electrical cardioversion. The aim of this animal study was to investigate the acute effect of repeated external defibrillation on coronary artery tissue and adjacent myocardium at the implantation site of coronary stents. Custom-made stainless steel stents were implanted in the coronary arteries of 7 dogs. Rapid ventricular pacing was performed to induce ventricular fibrillation. Defibrillation was achieved [5 J/kg; n=2 and 8 J/kg; n=3]. In 2 animals, coronary stent was implanted but defibrillation was not performed [control group]. The animal’s heart were excised and sent for microscopic examination. The light and electron micrographs of heart muscles showed no histological and ultrastructural changes in defibrillated and control dogs. It is concluded that nickel coating provides good resistance to heat in coronary stents and repeated defibrillation does not cause histopathological changes typical of thermal injury at the implantation site of coronary stent.  相似文献   
23.
There are an increasing number of neuroimaging studies that allow a better understanding of symptoms, neural correlates and associated conditions of fibromyalgia. However, the results of these studies are difficult to compare, as they include a heterogeneous group of patients, use different stimulation paradigms, tasks, and the statistical evaluation of neuroimaging data shows high variability. Therefore, this meta‐analytic approach aimed at evaluating potential alterations in neuronal brain activity or structure related to pain processing in fibromyalgia syndrome (FMS) patients, using quantitative coordinate‐based “activation likelihood estimation” (ALE) meta‐analysis. 37 FMS papers met the inclusion criteria for an ALE analysis (1,264 subjects, 274 activation foci). A pooled ALE analysis of different modalities of neuroimaging and additional analyses according functional and structural changes indicated differences between FMS patients and controls in the insula, amygdala, anterior/mid cingulate cortex, superior temporal gyrus, the primary and secondary somatosensory cortex, and lingual gyrus. Our analysis showed consistent results across FMS studies with potential abnormalities especially in pain‐related brain areas. Given that similar alterations have already been demonstrated in patients with other chronic pain conditions and the lack of adequate control groups of chronic pain subjects in most FMS studies, it is not clear however, whether these findings are associated with chronic pain in general or are unique features of patients with FMS. Hum Brain Mapp 37:1749–1758, 2016. © 2016 Wiley Periodicals, Inc .  相似文献   
24.
Human adenovirus C (HAdV-C) species are a common cause of respiratory infections and can occasionally produce severe clinical manifestations. A deeper understanding of the variation and evolution in species HAdV-C is especially important since these viruses, including HAdV-C6, are used as gene delivery vectors for human gene therapy and in other biotechnological applications. Here, the full-genome analysis of the prototype HAdV-C6 and a recently identified virus provisionally termed HAdV-C57 are reported. Although the genomes of all species HAdV-C members are very similar to each other, the E3 region, hexon and fiber (ten proteins total) present a wide range of identity values at the amino acid level. Studies of these viruses in comparison to the other three HAdV-C prototypes (1, 2, and 5) comprise a comprehensive analysis of the diversity and conservation within HAdV-C species. HAdV-C6 contains a recombination event within the constant region of the hexon gene. HAdV-C57 is a recombinant virus with a fiber gene nearly identical to HAdV-C6 and a unique hexon distinguished by its loop 2 motif.  相似文献   
25.
Genetic variation, C-reactive protein levels, and incidence of diabetes   总被引:7,自引:0,他引:7  
C-reactive protein (CRP) has been shown to be associated with type 2 diabetes, but whether CRP has a causal role is not yet clear. We examined the association in the Rotterdam Study, a population-based prospective cohort study. The association of baseline serum CRP and incident diabetes during follow-up was investigated, and a meta-analysis was conducted on the BMI-adjusted relation of CRP and diabetes. Furthermore, the association of CRP haplotypes with serum CRP and risk of diabetes was assessed. The age- and sex-adjusted hazard ratio for diabetes was 1.41 (95% CI 1.29-1.54) per 1 SD increase in natural logarithm of CRP, and it was 1.88, 2.16, and 2.83 for the second, third, and fourth quartiles of CRP, respectively, compared with the first quartile. The risk estimates attenuated but remained statistically significant after additional adjustment for obesity indexes, which agreed with the results of the meta-analysis. The most common genetic haplotype was associated with a significantly lower CRP level compared with the three other haplotypes. The risk of diabetes was significantly higher in the haplotype with the highest serum CRP level compared with the most common haplotype (OR 1.45, 95% CI 1.08-1.96). These findings support the hypothesis that serum CRP enhances the development of diabetes.  相似文献   
26.

Background  

Information about web-based education outcomes in comparison with a face-to-face format can help researchers and tutors prepare and deliver future web-based or face-to-face courses more efficiently. The aim of this study was to compare the effectiveness of web-based and face-to-face continuing education methods in improving nurses' knowledge about AIDS.  相似文献   
27.
Background: The higher consumption of fruit and vegetables is considered to be an indicator of healthy eating and the protective effects of fruit and vegetable (FV) consumption for noncommunicable diseases have been investigated extensively. The present study aimed to investigate the association between fruit and vegetable intake (FVI), health behaviours and socio‐demographic factors among adult Canadians. Methods: This analysis was based on the information from the Canadian Community Health Survey, Cycle 3.1. Daily intake of fruit and vegetables from a total number of 15 512 apparently healthy individuals, aged 18–64 years, were assessed using a structured questionnaire, which included 20 questions on the frequency of consumption of different types of fruit and vegetables. Multiple logistic regression models were used to determine the association between FVI and some socio‐economic factors and lifestyle behaviour among adult Canadians. Results: In total 77% of Canadian adults consumed fruit and vegetables less than five times per day. Females were more likely to consume more fruit [odds ratio (OR) 2.05; 95% confidence interval (CI) 1.75–2.4], vegetables (OR 1.95; 95% CI 1.65–2.29) and FV (OR 2.52; 95% CI 2.20–2.90) than males. Single/never married individuals, individuals with higher levels of education, never smokers, former drinkers and older people reported more consumption of fruit and vegetables than others. Conclusions: The results obtained in the present study indicate an association between FVI and some socio‐economic and healthy lifestyle behaviours, and that a substantial gap exists between the recommended level and the actual intake of the FV among the Canadian population. Because a higher intake of FV improves public health, it is imperative to tailor nutrition education at the individual and community levels in Canadian populations.  相似文献   
28.
29.
30.
This study aimed to assess the relationship between shift working and occupational exposure to noise with blood pressure (BP). The study was carried out in a rubber manufacturing company in 2010. Demographic, medical and occupational information for carrying out the study were collected through direct interview. All 331 under study workers were divided into four groups according to work shift and noise exposure severity, from non-noise exposed day time workers (Group 1) to noise exposed shift workers (Group 4). Finally, systolic and diastolic blood pressure levels were compared among these four groups. The results of this study showed that there was a significant difference between average systolic and diastolic BP and hypertension (HTN) frequency in the four groups (p<0.05). The highest rate of HTN and mean systolic and diastolic BP were observed among shift workers who were exposed to noise higher than permissible limit (Group 4). Also the results of logistic regression analysis showed that there was a significant relationship between simultaneous exposures to noise more than the permitted limit and shift work with HTN (p<0.05). The results of our study showed that shift working and simultaneous exposure to noise have an additive effect on occurrence of HTN. It is recommended that during periodic physical examinations of noise exposed shift workers, assessment of the cardiovascular system and BP should be done as well as the auditory system.  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