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   249篇
  免费   13篇
  国内免费   4篇
耳鼻咽喉   3篇
儿科学   25篇
妇产科学   3篇
基础医学   26篇
口腔科学   9篇
临床医学   37篇
内科学   45篇
皮肤病学   7篇
神经病学   3篇
特种医学   54篇
外科学   26篇
综合类   2篇
预防医学   8篇
眼科学   2篇
药学   9篇
中国医学   1篇
肿瘤学   6篇
  2022年   2篇
  2021年   3篇
  2018年   2篇
  2017年   3篇
  2016年   3篇
  2014年   5篇
  2013年   8篇
  2012年   4篇
  2011年   2篇
  2010年   2篇
  2009年   8篇
  2008年   2篇
  2007年   4篇
  2006年   4篇
  2005年   9篇
  2004年   5篇
  2003年   2篇
  2001年   5篇
  2000年   3篇
  1999年   3篇
  1998年   14篇
  1997年   14篇
  1996年   10篇
  1995年   13篇
  1994年   13篇
  1993年   13篇
  1992年   5篇
  1991年   9篇
  1990年   6篇
  1989年   4篇
  1987年   8篇
  1986年   7篇
  1985年   5篇
  1984年   5篇
  1983年   4篇
  1982年   5篇
  1981年   4篇
  1980年   5篇
  1979年   4篇
  1978年   6篇
  1976年   2篇
  1975年   3篇
  1973年   2篇
  1964年   1篇
  1962年   2篇
  1960年   1篇
  1958年   2篇
  1957年   5篇
  1945年   2篇
  1944年   1篇
排序方式: 共有266条查询结果,搜索用时 15 毫秒
21.
Occult cerebral vascular malformations: high-field MR imaging   总被引:4,自引:0,他引:4  
Occult cerebral vascular malformations (OCVMs) have characteristic appearances on high-field magnetic resonance (MR) images. These consist of circumscribed regions of low intensity, most prominent on T2-weighted images and representing hemosiderin deposits. Interspersed within most of these lesions are multiple areas of various signal intensity patterns, which correspond to hematomas in different stages of evolution and to fibrous regions containing calcium as well as hemosiderin. Forty-six lesions were found in 19 patients (34 supratentorial and 12 infratentorial). The supratentorial lesions tended to be subcortical or periventricular. Computed tomography depicted 24 of the 46 lesions demonstrated by high-field MR. Comparison of images obtained with both low-field MR (0.12 T and 0.35 T) and high-field MR (1.5 T) revealed that high-field MR imaging was superior in depicting OCVMs. High-field MR appears to be both sensitive and specific for OCVMs and may obviate the need for possible biopsy of these lesions.  相似文献   
22.
23.
24.
25.
26.
Sixty percent of newly diagnosed cancers occur in older adults and more complex planning is required to sustain quality care for older populations. Individualized care incorporating geriatric assessment can predict early mortality and treatment toxicity for older cancer patients. We mapped and summarized the available evidence on the integration of geriatric assessment into clinical oncology practice, and ascertained which domains have been implemented. We systematically searched bibliographic databases and trial registries for reports of clinical studies, clinical practice guidelines, systematic and non-systematic reviews, and grey literature published in English. We gathered data on study characteristics, geriatric domains and strategies evaluated, and relevant study objectives and findings. From a total of 10,124 identified citations, 38 articles met our eligibility criteria, 3 of which were clinical practice guidelines. Nearly half of these articles came from the United States. Domains of the geriatric assessment implemented in studies ranged from 1 to 12, with varied combinations. We identified 27 studies on strategies for implementing geriatric assessment and 24 studies on feasibility of implementing geriatric assessment, into clinical oncology practice. We also identified 3 main geriatric assessment models: 2 from the United States and 1 from Australia. Furthermore, we identified 2 reviews that reported varied components of geriatric assessment models. There is increasingly robust evidence to implement formal geriatric assessment in oncology practice. There remains a great deal of variation in the tools recommended to address each of the domains in a geriatric assessment, with only 1 guideline (American Society of Clinical Oncology guideline) settling on a specific best practice.Protocol registration: Open Science Framework osf.io/mec93.  相似文献   
27.
We report the first observation of successful kidney transplantation under pre‐emptive eculizumab treatment in a 7‐year‐old boy with atypical hemolytic uremic syndrome (aHUS) and a known hybrid CFH/CFHR1 gene, who was dependent on plasma therapy during the 3‐year dialysis period. The hybrid CFH/CFHR1 protein has an altered C3b/C3d binding, is incapable to protect cells from complement attack and is directly implicated in aHUS pathogenesis. There was no evidence of recurrence during the first 16‐month follow‐up period. We conclude that eculizumab alone, without plasma therapy (plasma infusion and/or plasma exchange), is sufficient to prevent recurrence of aHUS and to maintain long‐term graft function.  相似文献   
28.
Agenesis of the corpus callosum is a complex malformation of the brain that has been associated with varying degrees of limbic system maldevelopment. We retrospectively reviewed the records of 11 patients with callosal agenesis (seven total, four partial) who underwent magnetic resonance (MR) imaging, with particular attention to the associated malformations of the limbic system. Comparison was made with selected images from MR examinations of healthy volunteers and with necropsy specimens from other patients with callosal agenesis. Ten of 11 patients demonstrated limbic anomalies (severe motion artifact precluded evaluation of these structures in one patient). MR depicted not only the abnormalities intrinsic to callosal agenesis but also the frequently associated malformations of the limbic system.  相似文献   
29.
The resection of the columella and nasal depressor muscles is a simple operation to perform and one which allows an improvement in the facial physiognomy of many patients. This operation can be done alone or in conjunction with the classic rhinoplasty, thus achieving an improvement in the aesthetics of the smile. It has also been proved, contrary to common belief, that the action of these muscles has no connection with physiological breathing mechanisms.  相似文献   
30.
The purpose of this study was to investigate any influence of maternal and/or paternal age on gamete characteristics and pregnancy outcomes in intracytoplasmic sperm injection (ICSI) cycles. In all, 821 consecutive ICSI cases were analysed retrospectively. While a significant linear decline in semen volume was detected, no significant differences in the concentration, motility or morphology of the spermatozoa were found with paternal ageing. A significant decline in the number of oocytes retrieved and the number of mature oocytes obtained was found with advancing maternal age. An increase in the occurrence of digyny was noted with parental ageing, while no difference in single or bipronuclear fertilization was found. Older women had a decreased incidence of single pronucleus formation and an increase in digyny, but no significant difference in the percentage of oocytes that underwent two-pronuclear fertilization was detected with regard to maternal ageing. Pregnancy outcomes were not influenced by the age of the male partner, while a strong negative correlation was found with maternal ageing. To better analyse male partner ageing as a factor affecting pregnancy outcome, we analysed a subgroup of patients with a female partner aged <35 years who underwent ICSI. No paternal influence on ICSI pregnancy outcome was found in this subgroup of patients. We conclude that the influence on pregnancy outcome after ICSI is related mostly to maternal and not paternal age.   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