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   2073篇
  免费   178篇
  国内免费   7篇
耳鼻咽喉   32篇
儿科学   91篇
妇产科学   58篇
基础医学   247篇
口腔科学   47篇
临床医学   172篇
内科学   408篇
皮肤病学   29篇
神经病学   103篇
特种医学   474篇
外科学   160篇
综合类   76篇
预防医学   106篇
眼科学   30篇
药学   127篇
  1篇
中国医学   3篇
肿瘤学   94篇
  2023年   8篇
  2022年   10篇
  2021年   18篇
  2020年   19篇
  2019年   21篇
  2018年   27篇
  2017年   36篇
  2016年   31篇
  2015年   36篇
  2014年   51篇
  2013年   56篇
  2012年   55篇
  2011年   54篇
  2010年   58篇
  2009年   73篇
  2008年   51篇
  2007年   74篇
  2006年   65篇
  2005年   58篇
  2004年   46篇
  2003年   57篇
  2002年   36篇
  2001年   47篇
  2000年   47篇
  1999年   45篇
  1998年   95篇
  1997年   91篇
  1996年   90篇
  1995年   76篇
  1994年   51篇
  1993年   66篇
  1992年   16篇
  1991年   33篇
  1990年   35篇
  1989年   60篇
  1988年   48篇
  1987年   51篇
  1986年   56篇
  1985年   71篇
  1984年   40篇
  1983年   29篇
  1982年   33篇
  1981年   34篇
  1980年   37篇
  1979年   7篇
  1978年   19篇
  1977年   26篇
  1976年   23篇
  1975年   24篇
  1974年   10篇
排序方式: 共有2258条查询结果,搜索用时 15 毫秒
131.
132.
133.
134.
Multiple myeloma: evaluation by CT   总被引:3,自引:0,他引:3  
Schreiman  JS; McLeod  RA; Kyle  RA; Beabout  JW 《Radiology》1985,154(2):483-486
Although patients who have multiple myeloma usually have straightforward clinical symptoms and corroborative radiographs, in some instances, these patients will present atypically, with symptoms suggesting active disease but radiographs that are normal or nonspecific. We reviewed the records of 32 patients who had documented multiple myeloma and had undergone CT examinations, assessing the value of those examinations. Although CT is not indicated in all patients who have multiple myeloma, it is especially useful in patients who have bone pain and normal or nonspecific radiographs. CT provided confirmatory information in all cases in which lesions were seen on radiographs. CT also frequently demonstrated a greater extent of disease than could be appreciated on the radiographs.  相似文献   
135.
Cooper  KL; Beabout  JW; McLeod  RA 《Radiology》1985,157(1):15-17
Insufficiency fractures in the supraacetabular region were identified in five women, aged 55-83 years. Factors contributing to the diminished resistance of their bones included postmenopausal osteoporosis, steroid therapy, radiation therapy, and rheumatoid arthritis. The supraacetabular fractures were seen on routine radiographs as hazy bands of sclerosis located immediately above and parallel to the acetabular roof. All five patients had additional fractures in the spine or pelvis. Supraacetabular insufficiency fractures may be an unsuspected cause of hip pain, especially in older women.  相似文献   
136.
137.
138.
139.
140.
OBJECTIVE: Prospective trials have shown that 1-cm and 2-cm margins are safe for melanomas <1 mm thick and > or =1 mm thick, respectively. It is unknown whether narrower margins increase the risk of LR or mortality. SUMMARY BACKGROUND DATA: To determine the relationship between histopathologic excision margin, local recurrence (LR) and survival for patients with melanomas < or =2 mm thick. METHODS: Data were extracted from the Sydney Melanoma Unit database for all patients with cutaneous melanoma < or =2 mm thick, diagnosed up to 1996. Patients with positive excision margins or follow-up <12 months were excluded, leaving 2681 for analysis. Outcome measures were LR (recurrence <5 cm from the excision scar), in-transit recurrence, and disease-specific survival. Factors predicting LR and overall survival were tested with Cox proportional hazards analysis. RESULTS: Median follow-up was 83.8 months. LR was identified in 55 patients (median time to recurrence, 37 months). At 120 months, the actuarial LR rate was 2.9%. Five-year survival after LR was 52.8%. In multivariate analysis, only margin of excision and tumor thickness were predictive of LR (both P = 0.003). When all patients with a margin <0.8 cm in fixed tissue (corresponding to a margin of <1 cm in vivo) were excluded from analysis, margin was no longer significant in predicting LR. Thickness, ulceration, and site were predictive of survival, but margin was not (P = 0.49). CONCLUSIONS: Histopathologic margin affects the risk of LR. However, if the in vivo margin is > or =1 cm, it no longer predicts risk of LR. Patient survival is not affected by margin.  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