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   302篇
  免费   19篇
  国内免费   4篇
儿科学   8篇
妇产科学   1篇
基础医学   23篇
口腔科学   5篇
临床医学   22篇
内科学   65篇
皮肤病学   8篇
神经病学   2篇
特种医学   92篇
外科学   15篇
综合类   7篇
预防医学   29篇
眼科学   2篇
药学   17篇
中国医学   1篇
肿瘤学   28篇
  2023年   1篇
  2022年   1篇
  2021年   5篇
  2020年   4篇
  2019年   6篇
  2018年   6篇
  2017年   1篇
  2016年   1篇
  2015年   1篇
  2014年   6篇
  2013年   8篇
  2012年   15篇
  2011年   10篇
  2010年   17篇
  2009年   4篇
  2008年   7篇
  2007年   18篇
  2006年   23篇
  2005年   10篇
  2004年   12篇
  2003年   14篇
  2002年   7篇
  2001年   7篇
  2000年   11篇
  1999年   6篇
  1998年   7篇
  1997年   10篇
  1996年   8篇
  1995年   6篇
  1994年   6篇
  1993年   3篇
  1992年   2篇
  1990年   3篇
  1989年   3篇
  1988年   6篇
  1987年   14篇
  1986年   8篇
  1985年   6篇
  1984年   5篇
  1983年   2篇
  1982年   5篇
  1981年   5篇
  1980年   4篇
  1979年   3篇
  1978年   4篇
  1977年   5篇
  1976年   5篇
  1975年   4篇
排序方式: 共有325条查询结果,搜索用时 187 毫秒
1.
Background:  Previous studies into leisure have employed methodologies that may understate the significance of experiential components. This exploratory study investigated the leisure experiences of retired Australians over 65 years of age.
Methods:  Five semistructured interviews were used to explore the leisure experience of older people from metropolitan Adelaide. Data were coded and analysed thematically.
Results:  Relaxation and engrossment emerged as commonly expressed experiences, yet were found to emerge as a result of engagement in occupations predefined as leisure. Experiences of freedom from both necessary duties and a sense of obligation were discussed as potential determinants of leisure consciousness.
Practice implications:  This study highlights a need for therapists to actively access clients' subjective leisure experiences to enable engagement in personally meaningful leisure occupations.  相似文献   
2.
目的:明确集中的电话干预能否降低慢性心衰门诊患者死亡或因心衰加重而住院的发生率。设计:多中心、随机对照试验。地点:阿根廷的51个中心(包括公立、私立的医院及流动设施)。参与者:1518例患有稳定的慢性心衰且已接受最佳药物治疗方案治疗的门诊患者,由心脏科主治医师分层后随机分为电话干预组和常规治疗组。干预:在常规治疗的基础上,由一个中心通过护士频繁的电话随访对患者进行教育、辅导和监督。主要观察指标:全因死亡或由于心衰加重而住院。结果:99.5%的患者完成了全部随访。常规治疗组758例患者中由于心衰加重而住院或死亡的比例(235…  相似文献   
3.
4.
AIMS: Stenting has become an established interventional cardiology procedure for congenital heart disease. Although most stent procedures are completed successfully, complications may occur. This multicentre study evaluated early complications after stenting in patients with congenital heart disease, including potential risk factors. METHODS AND RESULTS: In this combined Dutch-Belgian retrospective study, 309 consecutive patients had undergone 366 catheterizations and received 464 stents in 13 different anatomical positions (418 sites). Seventy-two stenting-related complications (19%) occurred, of which 24 (5.7%) were major. Seven procedure-related deaths were documented (2.3%). Stent malpositioning and embolization were most common (7.7%). The use of non-premounted stents tended to be associated with higher complication rates. Centre inexperience with stenting and stenting of native vs. post-surgical stenosis tended to be associated with increased major complication rates. CONCLUSION: After stenting, complications are common for congenital heart disease. The vast diversity of stenotic sites combined with relatively small patient populations makes these procedures sensitive to complications. Combining operator experience may reduce the risks of stenting in congenital heart disease. The availability of premounted stents for greater vessel diameters will likely reduce incidences of stent migration and embolization.  相似文献   
5.
Kaposi's sarcoma-associated herpesvirus or human herpesvirus type8 (HHV-8) is present in all forms of Kaposi's sarcoma (KS) aswell as in primary effusion lymphomas and some cases of Castleman'sdisease. In KS tissues, HHV-8 is present in endothelial andspindle cells. Current serologic tests suggest that HHV-8 ispredominantly found in those at risk of KS and is not as widespreadas most other human herpesviruses. HHV-8 encodes various proteinsthat may play a role in promotion of cellular growth, includingcyclin- and G-coupled protein receptor homologues, and anti-apoptoticproteins, including Bcl-2, IL-6 (i.e., interleukin 6), and FLIP(i.e., FLICE inhibitory protein) homologues. In addition, HHV-8encodes two macrophage inflammatory-like proteins with anti-humanimmunodeficiency virus and angiogenic potential.  相似文献   
6.
Human herpesvirus 8 (HHV-8, also called KSHV) is linked to the etiopathogenesis of Kaposi's sarcoma (KS), multicentric Castleman's disease (MCD), and primary effusion lymphoma (PEL). The universal presence of HHV-8 in early KS has not yet been shown. We used a mAb (LN53) against latent nuclear antigen-1 (LNA-1) of HHV-8 encoded by ORF73 to study the distribution of the cell types latently infected by HHV-8 in patch, plaque, and nodular KS, MCD, and PEL. In early KS, HHV-8 is present in <10% of cells forming the walls of ectatic vessels. In nodular KS, HHV-8 is present in cells surrounding slit-like vessels and in >90% of spindle cells, but not in normal vascular endothelium. In addition, HHV-8 colocalizes with vascular endothelial growth factor receptor-3 (VEGFR-3), a marker of lymphatic and precursor endothelium. In early KS lesions, VEGFR-3 is more extensively expressed than LNA-1, indicating that HHV-8 is not inducing the proliferation of VEGFR-3-positive endothelium directly. In MCD, HHV-8 is present in mantle zone large immunoblastic B cells. No staining for LNA-1 is seen in samples from multiple myeloma, prostate cancer, and angiosarcoma, supporting the absence of any etiological link between these diseases and HHV-8.  相似文献   
7.
8.
Reported prevalences of human herpesvirus 8 (HHV-8) (Kaposi's sarcoma-associated herpesvirus) in semen have ranged widely. This is possibly due to differences in assay sensitivity, geographic or population-based differences in the true presence of the virus in semen, and PCR contamination. This study assessed interlaboratory sensitivity and reproducibility in the analysis of blinded experimental panels, each consisting of 48 specimens and being composed of semen specimens from different healthy artificial-insemination donors (n = 30) and human immunodeficiency virus (HIV)-infected patients (n = 7) plus positive (n = 4) and negative (n = 7) controls. The experimental panels analyzed in each laboratory were identical except for being independently coded. Of 10 experiments done in five laboratories, 5 experiments from three laboratories had evidence of PCR contamination; all instances of contamination were in the context of nested PCR procedures. In the experiments with no false-positive results, HHV-8 DNA was detected in three (8%) of the 37 semen specimens (two from artificial-insemination donors and one from an HIV-positive patient) but in only 3 (1.6%) of the 184 PCRs in which these specimens were analyzed. This suggests that HHV-8 DNA is present in semen at concentrations that can be too low to allow its consistent detection. This study emphasizes the importance of performing blinded, multi-institution experiments to provide a coherent basis for comparing results and to motivate standardization of methods.  相似文献   
9.
Multiple sclerosis: serial study of gadolinium-enhanced MR imaging   总被引:4,自引:0,他引:4  
Thirteen patients with definite multiple sclerosis (MS), studied 16-24 months previously with magnetic resonance (MR) imaging with and without enhancement by intravenously administered gadolinium diethylenetriaminepentaacetic acid (DTPA) dimeglumine, were reexamined with a similar protocol. Assessment of enhancement and clinical activity in both studies revealed that enhancement was observed in 13 of 14 cases in which clinical activity had changed within 4 weeks of the study and thus appeared more sensitive than clinical examination in determining active disease. The 3-minute postinjection, short repetition time image (TR) was the most efficient for depicting enhancement. Enhancing lesions (active plaques) arose from previously hyper- or isointense regions on long TR images. Previously active lesions reverted to areas of iso- or hyperintensity on long TR images. Serial comparison of long TR images in this population reveals a decrease in high-intensity lesions on long TR images in some cases and an increase in others. The findings of high-intensity regions on long TR images and previously enhancing lesions both becoming isointense suggests that transient inflammatory changes with concomitant edema without demyelination and/or with significant remyelination may occur in some MS lesions. MS lesions are dynamic; both active and inactive lesions may show dramatic change on longitudinal MR imaging studies.  相似文献   
10.
Corticosteroids are a mainstay of topical therapy for psoriasis. While efficacious and relatively safe when used carefully, the potential for side effects, notably skin atrophy and adrenal suppression, have been associated with excesses in potency, prolonged or widespread use. The International Psoriasis Council Working Group on Topical Therapy has reviewed the efficacy and safety of topical corticosteroids and recommends strategies for safe, long‐term use of these agents.  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