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   3050篇
  免费   168篇
  国内免费   32篇
耳鼻咽喉   31篇
儿科学   57篇
妇产科学   46篇
基础医学   448篇
口腔科学   37篇
临床医学   318篇
内科学   488篇
皮肤病学   109篇
神经病学   211篇
特种医学   258篇
外科学   257篇
综合类   9篇
预防医学   146篇
眼科学   47篇
药学   295篇
中国医学   56篇
肿瘤学   437篇
  2023年   23篇
  2022年   81篇
  2021年   84篇
  2020年   62篇
  2019年   59篇
  2018年   60篇
  2017年   77篇
  2016年   102篇
  2015年   129篇
  2014年   149篇
  2013年   182篇
  2012年   281篇
  2011年   250篇
  2010年   160篇
  2009年   138篇
  2008年   196篇
  2007年   176篇
  2006年   139篇
  2005年   154篇
  2004年   123篇
  2003年   99篇
  2002年   79篇
  2001年   67篇
  2000年   68篇
  1999年   62篇
  1998年   19篇
  1997年   18篇
  1996年   7篇
  1995年   11篇
  1994年   4篇
  1993年   10篇
  1992年   23篇
  1991年   25篇
  1990年   15篇
  1989年   22篇
  1988年   11篇
  1987年   11篇
  1986年   8篇
  1985年   5篇
  1984年   8篇
  1983年   6篇
  1978年   5篇
  1972年   4篇
  1971年   4篇
  1970年   3篇
  1969年   3篇
  1968年   5篇
  1966年   2篇
  1965年   2篇
  1962年   2篇
排序方式: 共有3250条查询结果,搜索用时 15 毫秒
61.
For comminuted shaft fracture of clavicle, the operative goal, aside from sound bone healing without complications of direct reduction, is maintenance of the original length in order to maintain the normal biomechanics of adjacent joint. Our bridge plating technique utilizing distraction through a lumbar spreader was expected to be effective for restoring clavicular length with soft tissue preservation. However, there are two disadvantages. First, there is more exposure to radiation compared to conventional plating; and second, it is difficult to control the rotational alignment. Despite these disadvantages, our technique has important benefits, in particular, the ability to preserve clavicular length without soft tissue injury around the fracture site.  相似文献   
62.
Park J‐C, Kim J.C, Kim B‐K, Cho K‐S, Im G‐I, Kim B‐S, Kim C‐S. Dose‐ and time‐dependent effects of recombinant human bone morphogenetic protein‐2 on the osteogenic and adipogenic potentials of alveolar bone‐derived stromal cells. J Periodont Res 2012; 47: 645–654. © 2012 John Wiley & Sons A/S Background and Objective: Recombinant human bone morphogenetic protein‐2 (rhBMP‐2) is a well‐known growth factor that can induce robust bone formation, and recent studies have shown that rhBMP‐2‐induced osteogenesis is closely related to adipogenesis. The aim of the present study was to determine the dose‐ and time‐dependent effects of rhBMP‐2 on the osteogenic and adipogenic differentiation of human alveolar bone‐derived stromal cells (hABCs) in vivo and in vitro. Material and Methods: hABCs were isolated and cultured, and then transplanted using a carrier treated either with or without rhBMP‐2 (100 μg/mL) into an ectopic subcutaneous mouse model. Comprehensive histologic and histometric analyses were performed after an 8‐wk healing period. To further understand the dose‐dependent (0, 10, 50, 200, 500 and 1000 ng/mL) and time‐dependent (0, 3, 5, 7 and 14 d) effects of rhBMP‐2 on osteogenic and adipogenic differentiation, in vitro osteogenic and adipogenic differentiation of hABCs were evaluated, and the expression of related mRNAs, including those for alkaline phosphatase, osteocalcin, bone sialoprotein, peroxisome‐proliferator‐activated receptor gamma‐2 and lipoprotein lipase, were assessed using quantitative RT‐PCR. Results: rhBMP‐2 significantly promoted the osteogenic and adipogenic differentiation of hABCs in vivo, and gradually increased both the osteogenic and adipogenic potential in a dose‐ and time‐dependent manner with minimal deviation in vitro. The expression of osteogenesis‐ and adipogenesis‐associated mRNAs were concomitantly up‐regulated by rhBMP‐2. Conclusion: The findings of the present study showed that rhBMP‐2 significantly enhanced the adipogenic as well as the osteogenic potential of hABCs in dose‐ and time‐dependent manner. The control of adipogenic differentiation of hABCs should be considered when regenerating the alveolar bone using rhBMP‐2.  相似文献   
63.
64.

Somali refugee youth present with a heightened risk for common mental disorders (CMDs), and yet few studies have discussed factors influencing mental health outcomes after psychosocial interventions. This study aimed to identify key factors that contribute to the improvement of CMD symptoms among Somali youth displaced in urban Kenya. Logistic regression analyses revealed that trauma exposure and emotional coping predict overall symptom improvement, pointing to a differential intervention effect on those with differing levels of religious belief and attitudes toward violence. This study provides insights into how psychosocial factors likely contribute to positive intervention outcomes in Somali refugee youth.

  相似文献   
65.

Introduction:

Infantile hemangiomas of the airway are diagnosed at bronchoscopy as part of the investigation of stridor or other respiratory symptoms. Here, we present three-dimensional computed tomography (3D-CT)/bronchoscopy findings of submucosal subglottic hemangioma missed at bronchoscopy.

Case Presentation:

We report on the clinical usefulness of 3D-CT/bronchoscopy as the primary diagnostic tool and follow-up method in the evaluation of suspected airway infantile hemangiomas, especially when the hemangioma is the submucosal type.

Conclusions:

3D-CT/bronchoscopy will reduce the need for invasive laryngoscopic studies and help to diagnose submucosal hemangiomas undetected on laryngoscope. Additionally, 3D-CT/bronchoscopy will help evaluating the extent of the lesion, degree of airway narrowing, and treatment response.  相似文献   
66.
67.
68.
69.
PURPOSE: To investigate the general characteristics of glucose metabolism distribution and the functional deficit in the brain of children with developmental language delay (DLD), we compared functional neuroradiological studies such as positron emission tomography (PET) of a patient group of DLD children and a control group of attention- deficit hyperactivity disorder (ADHD) children. PATIENTS AND METHODS: Seventeen DLD children and 10 ADHD children under 10 years of age were recruited and divided into separate groups consisting of children less than 5 years of age or between 5 and 10 years of age. The PET findings of 4 DLD children and 6 control children whose ages ranged from 5 to 10 years were compared by Statistical Parametric Mapping (SPM) analysis. RESULTS: All of the DLD children revealed grossly normal findings in brain MRIs, however, 87.5% of them showed grossly abnormal findings in their PET studies. Abnormal findings were most frequent in the thalamus. The patient group showed significantly decreased glucose metabolism in both frontal, temporal and right parietal areas (p < 0.005) and significantly increased metabolism in both occipital areas (p < 0.05) as compared to the control group. CONCLUSION: This study reveals that DLD children may show abnormal findings on functional neuroradiological studies, even though structural neuroradiological studies such as a brain MRI do not show any abnormal findings. Frequent abnormal findings on functional neuroradiological studies of DLD children, especially in the subcortical area, suggests that further research with quantitative assessments of functional neuroradiological studies recruiting more DLD children and age-matched normal controls could be helpful for understanding the pathophysiology of DLD and other disorders confined to the developmental disorder spectrum.  相似文献   
70.
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