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   2083篇
  免费   117篇
  国内免费   21篇
耳鼻咽喉   4篇
儿科学   87篇
妇产科学   24篇
基础医学   164篇
口腔科学   73篇
临床医学   248篇
内科学   477篇
皮肤病学   7篇
神经病学   101篇
特种医学   174篇
外科学   232篇
综合类   100篇
一般理论   4篇
预防医学   238篇
眼科学   31篇
药学   80篇
肿瘤学   177篇
  2023年   9篇
  2022年   11篇
  2021年   29篇
  2020年   13篇
  2019年   20篇
  2018年   21篇
  2017年   16篇
  2016年   30篇
  2015年   22篇
  2014年   45篇
  2013年   58篇
  2012年   96篇
  2011年   81篇
  2010年   52篇
  2009年   70篇
  2008年   87篇
  2007年   111篇
  2006年   109篇
  2005年   101篇
  2004年   94篇
  2003年   76篇
  2002年   54篇
  2001年   75篇
  2000年   76篇
  1999年   64篇
  1998年   55篇
  1997年   50篇
  1996年   41篇
  1995年   49篇
  1994年   34篇
  1993年   39篇
  1992年   40篇
  1991年   30篇
  1990年   31篇
  1989年   53篇
  1988年   46篇
  1987年   36篇
  1986年   21篇
  1985年   35篇
  1984年   26篇
  1983年   21篇
  1982年   27篇
  1981年   17篇
  1980年   22篇
  1979年   14篇
  1978年   15篇
  1977年   16篇
  1976年   13篇
  1974年   10篇
  1971年   7篇
排序方式: 共有2221条查询结果,搜索用时 15 毫秒
1.
2.
3.
Coronary artery bypass grafts: visualization with MR imaging   总被引:1,自引:0,他引:1  
Gomes  AS; Lois  JF; Drinkwater  DC  Jr; Corday  SR 《Radiology》1987,162(1):175
  相似文献   
4.
Hysterosalpingography was performed in 31 patients by means of a low-dose scanning-beam digital radiographic system. The technique permits adequate evaluation of gynecologic abnormalities while allowing significant reduction in radiation: 2.4-mR (6.1 X 10(-7) C/kg) exposure to the skin and 0.7-mrad (7 X 10(-6) Gy) mean dose to the ovaries per image obtained. Sixteen patients demonstrated readily recognizable and documented abnormalities, corroborated by laparoscopy, laparotomy, or other supportive evidence.  相似文献   
5.
6.
7.
BACKGROUND: Merkel cell carcinoma is a rare malignant neuroendocrine neoplasm characteristically arising from the dermis of sunlight-exposed skin. It rarely arises outside the skin. OBJECTIVE: We present a patient with primary Merkel cell carcinoma arising from subcutaneous fat, with no involvement of the overlying skin. We describe the clinical manifestations and magnetic resonance imaging (MRI) findings. METHODS: We report a 63-year-old woman with a primary lesion of Merkel cell carcinoma that arose from the subcutaneous fat layer of the left arm. The lesion presented as a subcutaneous nodule with intact overlying skin. MRI showed that the nodular lesion was located entirely in the subcutaneous fat layer, with no involvement of the dermis. Peritumoral infiltration around the lesion and enlarged lymph nodes deep to the lesion were noted. The patient received wide excision of the lesion with dissection of the regional lymph nodes and adjuvant radiotherapy and chemotherapy. RESULTS: Histopathologic examination confirmed the diagnosis of Merkel cell carcinoma with local lymphatic metastasis, and the lesion was completely located in the subcutaneous fat, with no involvement of the dermis. These findings were well correlated with MRI findings. CONCLUSION: Primary Merkel cell carcinoma may arise from the subcutaneous fat and present as an entirely subcutaneous lesion with intact skin. MRI is helpful to evaluate the local extension of the lesion and regional lymphatic metastasis.  相似文献   
8.
Mumps orchitis   总被引:3,自引:0,他引:3  
A L Manson 《Urology》1990,36(4):355-358
  相似文献   
9.
表小檗碱对α受体的作用   总被引:2,自引:0,他引:2  
王嘉陵  方达超 《药学学报》1990,25(4):289-292
表小檗碱(epiberberine,EB)是从湖北产黄连(Coptis chinensis Franch)中提取的一种生物碱,属苯喹嗪类原小檗碱,对其药理作用的研究资料甚少,未见其对α肾上腺素体作用的报道。资料表明,许多原小檗碱类化合物有α受体阻滞作用,为从该类化合物中选择  相似文献   
10.
We report the results of intensive therapy and autologous bone marrow transplantation (BMT) in 23 patients with malignant lymphoma (eight Hodgkin's disease and 15 non-Hodgkin's lymphoma) who failed primary therapy. All patients had evidence of disease prior to transplant therapy: 10 had never achieved a complete remission and 13 were in relapse. The preparative regimen included involved field radiation followed by fractionated total body irradiation and high dose cyclophosphamide. A complete remission was achieved in 15 patients, 11 of whom continue in unmaintained complete remission from 27 to 72 months after BMT (median follow-up of 52 months). Of the remaining patients, five did not achieve a complete remission and three died of early toxicity. The event-free survival of the entire group is 47%. Disease status at the time of BMT was significantly correlated with patient outcome. The event-free survival of 13 patients in whom there was no objective evidence of tumor growth on conventional dose therapy was 77% compared with only 10% in patients with tumors progressing on conventional dose therapy (p less than 0.002). All six patients transplanted in untreated relapse continue in unmaintained remission, suggesting that debulking chemotherapy may not be necessary before BMT. Alternative approaches are needed in patients whose tumors progress on conventional dose therapy.  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