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   8473篇
  免费   540篇
  国内免费   105篇
耳鼻咽喉   101篇
儿科学   130篇
妇产科学   152篇
基础医学   888篇
口腔科学   292篇
临床医学   694篇
内科学   2550篇
皮肤病学   115篇
神经病学   752篇
特种医学   295篇
外国民族医学   1篇
外科学   1538篇
综合类   23篇
一般理论   1篇
预防医学   362篇
眼科学   111篇
药学   404篇
中国医学   8篇
肿瘤学   701篇
  2023年   140篇
  2022年   237篇
  2021年   502篇
  2020年   291篇
  2019年   340篇
  2018年   391篇
  2017年   276篇
  2016年   317篇
  2015年   328篇
  2014年   435篇
  2013年   496篇
  2012年   693篇
  2011年   630篇
  2010年   342篇
  2009年   329篇
  2008年   456篇
  2007年   425篇
  2006年   412篇
  2005年   347篇
  2004年   262篇
  2003年   240篇
  2002年   168篇
  2001年   86篇
  2000年   88篇
  1999年   85篇
  1998年   46篇
  1997年   35篇
  1996年   33篇
  1995年   35篇
  1994年   27篇
  1992年   56篇
  1991年   36篇
  1990年   32篇
  1989年   51篇
  1988年   37篇
  1987年   41篇
  1986年   40篇
  1985年   28篇
  1984年   20篇
  1983年   17篇
  1982年   12篇
  1979年   29篇
  1978年   19篇
  1976年   13篇
  1974年   21篇
  1973年   20篇
  1972年   16篇
  1969年   21篇
  1967年   14篇
  1966年   12篇
排序方式: 共有9118条查询结果,搜索用时 421 毫秒
91.
Respiratory complications are common in the patient with muscular dystrophy. The periodic clinical and instrumental respiratory evaluation is extremely important. Despite the presence in the literature of updated guidelines, patient associations often report lack of knowledge of these pathologies, particularly in peripheral hospitals. The purpose of this work, inspired by the Italian Muscular Dystrophy Association (UILDM) is to improve management of respiratory problems necessary for the management of these patients complex. To this end, the main items that the specialist can meet in the follow-up of these pathologies have been analyzed and discussed, among which the respiratory basal evaluation, the criteria of adaptation to non-invasive ventilation, management of bronchial secretions, situations of respiratory emergency, indications for tracheostomy and the subject of advance directives of treatment (DAT).Key words: respiratory failure, muscular dystrophy, cough efficacy, spirometry, polygraphy, non-invasive ventilation, arterial blood gases, cough machine, invasive ventilation, tracheostomy, mechanical ventilation  相似文献   
92.
This research aims at supporting hospital management in making prompt Operating Room (OR) planning decisions, when either unpredicted events occur or alternative scenarios or configurations need to be rapidly evaluated. We design and test a planning tool enabling managers to efficiently analyse several alternatives to the current OR planning and scheduling. To this aim, we propose a decomposition approach. More specifically, we first focus on determining the Master Surgical Schedule (MSS) on a weekly basis, by assigning the different surgical disciplines to the available sessions. Next, we allocate surgeries to each session, focusing on elective patients only. Patients are selected from the waiting lists according to several parameters, including surgery duration, waiting time and priority class of the operations. We performed computational experiments to compare the performance of our decomposition approach with an (exact) integrated approach. The case study selected for our simulations is based on the characteristics of the operating theatre (OT) of a medium-size public Italian hospital. Scalability of the method is tested for different OT sizes. A pilot example is also proposed to highlight the usefulness of our approach for decision support. The proposed decomposition approach finds satisfactory solutions with significant savings in computation time.  相似文献   
93.
94.
The use of percutaneous renal tumour biopsy (RTB) as a diagnostic tool for the histological characterization of renal masses has increased dramatically within the last 30 years. This increased utilization has paralleled advances in imaging techniques and an evolving knowledge of the clinical value of nephron sparing surgery. Improved biopsy techniques using image guidance, coupled with the use of smaller gauge needles has led to a decrease in complication rates. Reports from series containing a large number of cases have shown the non‐diagnostic rate of RTB to range from 4% to 21%. Re‐biopsy has been shown to reduce this rate, while the use of molecular markers further improves diagnostic sensitivity. In parallel with refinements of the biopsy procedure, there has been a rapid expansion in our understanding of the complexity of renal cell neoplasia. The 2013 Vancouver Classification is the current classification for renal tumours, and contains five additional entities recognized as novel forms of renal malignancy. The diagnosis of tumour morphotype on RTB is usually achievable on routine histology; however, immunohistochemical studies may be of assistance in difficult cases. The morphology of the main tumour subtypes, based upon the Vancouver Classification, is described and differentiating features are discussed.  相似文献   
95.
The rotator cuff tear is one of the most frequent musculoskeletal disorders, but the real incidence is not clearly known because it’s usually asymptomatic, even if it’s more common in patients with shoulder pain (36 %). The prevalence of the complete tear among general population is estimated approximately around 20.7 % and it is more usual with the increasing of the age. The aim of this study is to evaluate a group of patients with any size of full-thickness cuff tear treated by arthroscopic technique, comparing the clinical and functional recovery (isokinetic, isotonic and isometric strength) with the un-operated side. Between October 2009 and June 2011, 74 patients, mean age 59 (20–72) years old, underwent arthroscopic treatment for rotator cuff tear. Forty-two patients were finally included in the study, 20 men and 22 women, mean age of 55 (20–68) years old. The mean follow-up was 12 months (6–23 months). The strength of each patient’s shoulder, both operated and un-operated, was evaluated using isokinetic, isotonic and isometric tests (BIODEX Medical System). The functional outcome showed no significant differences between operated and un-operated shoulder, confirmed by Constant–Murley score and DASH score. The isokinetic, isotonic and isometric tests are valid support to clinical evaluation in order to obtain an objective data on shoulder recovery.  相似文献   
96.
Observing models displaying facial expressions of pain elicits neural activity in onlookers’ neural structures involved in first-hand experience of pain and in monitoring conflicting information. We investigated whether the purported conflict between the pain and its emotional expression in a model modulates cortical responses elicited by nociceptive laser stimuli in an onlooker. Seeing happy facial expressions, incongruent with the perceptual status attributed to the model, determined a significant reduction in the laser-evoked N2 potential. One of the main sources of this response is the anterior cingulate cortex, an area involved in pain perception, empathy for pain and conflict detection. A pre-activation of the anterior cingulate cortex due to the detection of the emotional conflict may, therefore, be responsible for the reduction of nociceptive-related response in the same brain area. Thus, top–down variables, like the appraisal of the others’ emotional status, modulate onlookers’ nociceptive-related neural activity.  相似文献   
97.
Objective: The first goal of our study was to investigate major determinants of aortic stiffness in postmenopausal women using an echocardiographic method to calculate global pulse wave velocity (PWVg) rather than the less accurate carotid–femoral pulse wave velocity (PWVc). The second goal was to relate PWVg to the absolute risk of major cardiovascular (CV) events estimated by CV risk factors. Patients and methods: Two hundred forty‐four consecutive women who presented to our heart station were screened. One hundred twenty‐two were postmenopausal, either natural or surgical, whereas 122 were premenopausal. The mean age of the patients was 54 ± 13 years. Individuals were categorized as current smokers, former smokers, or nonsmokers and hypertensive or not. Hypercholesterolemia and diabetes mellitus were defined. Aortic stiffness was assessed by PWVg measured with pulsed Doppler, the interval between the beginning of QRS complex and the foot of the systolic upstroke in the Doppler spectral envelope was calculated at the aortic valve site and at the right common femoral artery. PWVg was calculated between the aortic valve and right common femoral artery by dividing the straight line distance between the two by the transit time. Results: There was a highly significant statistical difference (P < 0.0012) in PWVg between menstruating women and postmenopausal women. Similarly, this difference in PWVg was also noted among the menstruating population (P < 0.0014) when comparing normotensive women and hypertensive women. In postmenopausal women, PWVg was 6.8 m/sec in normotensive women and 7.56 m/sec in hypertensive women (P < 0.007). Conclusion: PWVg was increased in postmenopausal women compared with menstruating women. Systemic hypertension has an independent, but additive effect on aortic stiffness assessed by PWVg. Our study supports the usefulness of the assessment of aortic stiffness as a marker of CV disease and to identify subjects at risk at an early age.  相似文献   
98.
An overview on children's wheelchair positioning in France. A French team working in a special center has made a clinical approach and gives their conclusions.  相似文献   
99.
100.
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