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   2599篇
  免费   97篇
  国内免费   11篇
耳鼻咽喉   83篇
儿科学   91篇
妇产科学   127篇
基础医学   328篇
口腔科学   34篇
临床医学   154篇
内科学   655篇
皮肤病学   44篇
神经病学   267篇
特种医学   46篇
外科学   170篇
综合类   17篇
预防医学   207篇
眼科学   59篇
药学   277篇
中国医学   2篇
肿瘤学   146篇
  2023年   14篇
  2022年   104篇
  2021年   125篇
  2020年   40篇
  2019年   70篇
  2018年   62篇
  2017年   62篇
  2016年   65篇
  2015年   82篇
  2014年   118篇
  2013年   137篇
  2012年   226篇
  2011年   225篇
  2010年   110篇
  2009年   94篇
  2008年   146篇
  2007年   186篇
  2006年   181篇
  2005年   180篇
  2004年   150篇
  2003年   150篇
  2002年   122篇
  2001年   5篇
  2000年   2篇
  1999年   4篇
  1998年   8篇
  1997年   4篇
  1996年   6篇
  1995年   8篇
  1994年   2篇
  1992年   1篇
  1991年   2篇
  1990年   7篇
  1988年   2篇
  1987年   1篇
  1984年   1篇
  1981年   1篇
  1974年   1篇
  1972年   1篇
  1967年   1篇
  1925年   1篇
排序方式: 共有2707条查询结果,搜索用时 15 毫秒
991.
992.
993.
AIM:To evaluate the clinical significance of-765G/C and-1195G/A cyclooxygenase-2 (COX-2) gene polymorphisms in patients with pancreatic cancer (PC).METHODS:The study included 201 patients:85 with PC and 116 healthy controls.-765G/C and-1195G/A COX-2 gene polymorphisms were studied in DNA isolated from blood samples.The associations of the analyzed genotypes and clinical data at diagnosis were evaluated.RESULTS:We found an increased frequency of the homozygous-1195AA COX-2 genotype in patients with PC (53.7%...  相似文献   
994.
995.
Aim The aim of the study was to estimate the influence of percutaneous endoscopic gastrostomy (PEG) placement on gastro‐oesophageal reflux (GOR) by using multiple intraluminal impedance (MII/pH) measurements in children with neurological impairments. Method Fifteen children with neurological impairments (cerebral palsy, n=10; cerebroidolipofuscinosis, n=2; Aicardi syndrome, n=1; and secondary encephalopathy, n=2) were investigated (interquartile range [IQR] 6y 4mo–14y 8mo; median age 10y 2mo; eight male, seven female). Individuals with nutritional disorders that could not be corrected by physiological means or with swallowing disorders that either caused chronic respiratory symptoms or prevented food intake were included in the study. The exclusion criteria included previous major abdominal surgery and a lack of consent for PEG. Participants underwent MII/pH for a 24‐hour period and had an oesophagogastroduodenoscopy before PEG placement, which was repeated 6 to 8 months later. Results At baseline, GOR was detected in 6 of the 15 participants, and the second MII/pH session revealed GOR in 2 of the 15 children. Differences between quantitative GOR indices obtained before and after PEG were not statistically significant, except for the proportion of the acidic/weakly acidic reflux events – among all participants in the first examination, 159 reflux episodes were acidic and 244 were weakly acidic, while in the follow‐up recordings the proportion was inverted (244 acidic, 136 weakly acidic; χ2=47.0; p<0.001). Baseline endoscopy did not reveal any macroscopic changes in any of the examined individuals, but the follow‐up examination revealed oesophagitis in two participants. The median body weight gain after 6 months as 22.0% (IQR 14.4–29.2%). All participants tolerated PEG feeding well, regardless of MII/pH results. Interpretation Identification of GOR based on MII/pH in children with neurological impairments does not exclude a good clinical response to PEG feeding.  相似文献   
996.

Purpose

Use of concomitant medicines (CMs) is a common practice in people with epilepsy, as comorbidity in this group is frequent. Comedication, especially if it is self-administered, may pose significant hazards due to potential interactions. Some attention has been given to use of CMs in older patients with epilepsy but the CM habits of younger patients are much less known. The purpose of this study was to determine annual frequency of use, kind and cost of CMs in patients with epilepsy.

Material and methods

The 12-month prospective multicentre study included 772 patients with a mean age of 27.4 yrs and a mean epilepsy duration of 12.5 yrs. Data on patient characteristics and treatment were collected during consecutive five visits. All CMs were classified according to the ATC system.

Results

Of the 772 patients, 472 (61.1%) used at least one CM (3.4 drug/patient). OTC drugs constituted nearly 2/3 of all CMs. More women then men took CMs (p < 0.002). The patients taking CMs were significantly older, had longer duration of epilepsy, more frequent comorbidities, and more seizures than patients not receiving any CM. Alimentary tract and metabolism drugs (28.9%), nervous system drugs (19.8%) and cardiovascular system drugs (11%) were the ones most commonly used. The annual cost of CMs was 76011.9 € PPP (mean cost/patient – 161.0 € PPP).

Conclusions

The results confirm that patients with epilepsy, regardless of age, take commonly CMs. Physicians should be more aware of this practice.  相似文献   
997.
998.
999.
Background and purposeThe influence of sex hormones on immune system activity in multiple sclerosis (MS) has been suggested by clinical evidence. The aim of the study was to analyse the pattern of sex hormones in MS women and to correlate the hormone pattern abnormalities to the disease course as well as to the magnetic resonance imaging (MRI) results.Material and methodsWe studied the serum level of the progesterone, β-oestradiol and prolactin in 46 women with clinical definite MS aged from 19 to 65; mean disease duration was 11.80 ± 9.86 years. The evaluation of the intensity of hormonal changes was done using a scoring system (0–3). On the brain MRI, the presence of brain atrophy, of hypothalamic demyelination as well as demyelination intensity (or degree) were analysed. The evaluation of the degree of demyelination and brain atrophy was done using a scoring system (0–4).ResultsThe main hormonal abnormalities consisted of decreased progesterone level, increased oestradiol level or both. The sex hormone pattern was abnormal in 56% of patients. Hypothalamic lesions were found on MRI in 53% of cases. The abnormal hormonal pattern correlated with intensity of MR changes (p < 0.05, Fisher's exact test), but neither with presence of hypothalamic changes nor with disease parameters (Expanded Disability Status Scale, relapse rate, disease duration).ConclusionsIt is important to check the hormonal pattern in MS women because according to our results it may be related to the disease activity and probably affects the type of therapeutic intervention. This pilot study will be extended in a larger population.  相似文献   
1000.
Heath related quality of life has been an important object of interest in the clinical practice, focused on assessment of treatment effects from patient's point of view, with particular emphasis placed on effect of treatment on daily patient functioning. Concept of health-related quality of life needs valid and reliable instruments.The aim of the study was to present the process of validation of a new version of EORTC QLQ-CR29 module in Polish patients suffering from rectal cancer.Material and methods. EORTC QLQ-CR29 module comprises 29 questions, and was adapted to Polish cultural conditions based on EORTC procedure. Data collected from 20 patients were analyzed, their agreement with theoretical and empirical structure was assessed. Convergent and discriminant validity were analyzed with multi trait scaling.Reliability was assessed with Cronbach alpha coefficient. Known group validity was assessed in terms of differences between men and women, and between stoma and non-stoma patients. Exact Mann-Whitney test was used. P values lower than 0.05 were considered significant.Results. Scales built on bases of empirical model of module had higher validity and reliability than those based on theoretical model.There were no significant differences between men and women in health-related quality of life. Significantly higher values were observed in non-stoma patients on body image scale and for leakage of stool item. Reversed relationship was observed in case of abdominal and buttocks pain, as well as embarrassment because of bowel movements.Conclusions. Module CR29 is a valid and reliable tool, which enables standardized measurement of treatment effects, suggested for use as main tool measuring impact of disease itself and applied treatment on health-related quality of life of rectal cancer patients.  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