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   1879篇
  免费   143篇
  国内免费   11篇
耳鼻咽喉   35篇
儿科学   46篇
妇产科学   23篇
基础医学   294篇
口腔科学   40篇
临床医学   146篇
内科学   475篇
皮肤病学   36篇
神经病学   86篇
特种医学   25篇
外科学   329篇
综合类   43篇
一般理论   9篇
预防医学   125篇
眼科学   49篇
药学   123篇
中国医学   36篇
肿瘤学   113篇
  2023年   20篇
  2022年   52篇
  2021年   76篇
  2020年   44篇
  2019年   90篇
  2018年   86篇
  2017年   43篇
  2016年   63篇
  2015年   51篇
  2014年   66篇
  2013年   120篇
  2012年   149篇
  2011年   168篇
  2010年   66篇
  2009年   78篇
  2008年   105篇
  2007年   116篇
  2006年   78篇
  2005年   76篇
  2004年   77篇
  2003年   75篇
  2002年   67篇
  2001年   28篇
  2000年   33篇
  1999年   24篇
  1998年   14篇
  1997年   3篇
  1996年   3篇
  1995年   5篇
  1994年   8篇
  1992年   12篇
  1991年   12篇
  1990年   6篇
  1989年   13篇
  1988年   11篇
  1987年   9篇
  1986年   11篇
  1985年   6篇
  1984年   3篇
  1983年   5篇
  1979年   8篇
  1977年   3篇
  1975年   5篇
  1974年   8篇
  1972年   3篇
  1971年   2篇
  1970年   4篇
  1969年   5篇
  1968年   5篇
  1967年   4篇
排序方式: 共有2033条查询结果,搜索用时 15 毫秒
101.
102.
Esmat AY  Refaie FM  Shaheen MH  Said MM 《Tumori》2002,88(6):513-521
In the present study the chemopreventive activities of DFMO, the irreversible inhibitor of ornithine decarboxylase, and finasteride, the inhibitor of prostatic 5a-reductase, against the development of chemically induced prostate adenocarcinoma by methylnitrosourea/testosterone propionate in male Wistar rats were investigated. According to histological examination, oral administration of DFMO and finasteride, either alone or combined, for two months to MNU/TP-inoculated rats reduced the tumor incidence to 11.11%, 10% and 10%, respectively, compared to tumored controls (64.3%). DFMO and/or finasteride treatment resulted in significant reductions in the wet weight of the prostate gland and seminal vesicles and its ratio relative to the total body weight, as well as the levels of prostate total protein, DNA, RNA and DNA/RNA ratio, compared to tumored controls. However, the effect of the combined treatment was of no statistical significance compared to single DFMO or finasteride treatment, as demonstrated by the non-significant differences between the mean values of most of the studied parameters. The tumor chemopreventive activity and the prostate growth inhibitory effect of DFMO and finasteride were due to suppression of prostate polyamine synthesis. ANOVA test revealed that the relative weight of the prostate as well as blood and tissue polyamine levels could be used as significant endpoint biomarkers for DFMO and finasteride as cancer chemopreventive agents.  相似文献   
103.
PURPOSE: To assess the outcome of papillary lesions, radial scars, or lobular carcinoma in situ (LCIS) diagnosed at stereotactic core-needle biopsy (SCNB). MATERIALS AND METHODS: Retrospective review of 1,236 lesions sampled with SCNB yielded 22 papillary lesions, nine radial scars, and five LCIS lesions. Diffuse lesions such as papillomatosis, papillary ductal hyperplasia, papillary ductal carcinoma in situ (DCIS), and atypical lobular hyperplasia were not included. The mammographic findings, associated histologic features, and outcome were assessed for each case. RESULTS: Sixteen papillary lesions were diagnosed as benign at SCNB. Of these, five were benign at excision, and 10 were unremarkable at mammographic follow-up. At excision of an unusual lesion containing a microscopic papillary lesion, DCIS was found. Three of four papillary lesions suspicious at SCNB proved to be papillary carcinomas; the fourth had no residual carcinoma at excision. Eight of nine radial scars were excised, which revealed atypical hyperplasia in four scars but no malignancies. One LCIS lesion was found at excision to contain DCIS. CONCLUSION: Benign or malignant papillary lesions were accurately diagnosed with SCNB in the majority of cases. Cases diagnosed as suspicious for malignancy or with atypia or unusual associated histologic findings should be excised. No malignancies were found at excision of radial scars diagnosed at SCNB. Surgical removal of these lesions following SCNB may not be routinely necessary. DCIS was found in one lesion diagnosed as LCIS at SCNB, which suggests that removal of these lesions may be prudent.  相似文献   
104.
105.
A bstract Since 1980, the automatic implantable cardioverter defibrillator (ICD) has evolved as effective therapy for prevention of sudden cardiac death following documented sustained ventricular tachycardia or fibrillation. During a 5-year period, 412 ICD devices were implanted at the University of Michigan Hospitals with a wound complication rate of 4.1%. In this group, there were 13 infections, 3 erosions of the generator pocket, and 1 wound hematoma. Of the 16 patients with infection or erosion, 12 patients were treated with a rectus abdominis muscle flap closure and 4 with ICD generator removal. In 83% (n = 12) of the muscle flap patients, the wound healed uneventfully. Preoperative chest CT scanning was found to be helpful in identifying probable infection of the epicardial leads. In these cases, all hardware had to be removed to achieve resolution of the infection. We concluded that rectus abdominis muscle flaps were helpful in salvaging infected or exposed ICD generators in the absence of infected epicardial leads.  相似文献   
106.
107.
108.
We outline a proposal for the use of living unrelated kidney donors for transplantation. This proposal, although recommended by the Saudi National Committee on Renal Transplantation, is still under discussion and has not been implemented yet. We feel that this proposal is ethical with airtight safeguards against commercialization and for the protection of the well-being of the donor with assurance that he or she has not been coerced into donation.  相似文献   
109.
110.
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