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   7624篇
  免费   446篇
  国内免费   28篇
耳鼻咽喉   54篇
儿科学   164篇
妇产科学   127篇
基础医学   975篇
口腔科学   186篇
临床医学   617篇
内科学   2317篇
皮肤病学   155篇
神经病学   632篇
特种医学   168篇
外科学   1090篇
综合类   71篇
一般理论   1篇
预防医学   556篇
眼科学   206篇
药学   448篇
中国医学   16篇
肿瘤学   315篇
  2023年   48篇
  2022年   95篇
  2021年   264篇
  2020年   131篇
  2019年   199篇
  2018年   264篇
  2017年   140篇
  2016年   215篇
  2015年   210篇
  2014年   315篇
  2013年   375篇
  2012年   561篇
  2011年   598篇
  2010年   361篇
  2009年   306篇
  2008年   481篇
  2007年   545篇
  2006年   515篇
  2005年   425篇
  2004年   430篇
  2003年   370篇
  2002年   350篇
  2001年   74篇
  2000年   66篇
  1999年   55篇
  1998年   65篇
  1997年   53篇
  1996年   39篇
  1995年   33篇
  1994年   33篇
  1993年   42篇
  1992年   39篇
  1991年   27篇
  1990年   23篇
  1989年   24篇
  1988年   28篇
  1987年   19篇
  1986年   16篇
  1985年   15篇
  1984年   25篇
  1983年   29篇
  1982年   20篇
  1981年   22篇
  1980年   16篇
  1979年   10篇
  1978年   12篇
  1977年   20篇
  1976年   12篇
  1975年   10篇
  1974年   13篇
排序方式: 共有8098条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
5.
6.
7.
OBJECTIVES: To determine whether aromatase expression in the eutopic endometrium and adenomyotic foci is affected by previous use of oral contraceptives containing gestodene, and to determine whether changes in cyclooxygenase-2 (COX-2) expression occur in adenomyosis during the menstrual cycle. PATIENT AND METHODS: This was a retrospective cohort study carried out in paraffin-embedded endometrial tissue obtained from patients with a histological diagnosis of adenomyosis obtained during the proliferative (n = 25) and luteal (n = 10) phases of the menstrual cycle and following the use of continuous oral contraception with gestodene/ethinyl estradiol (n = 7). COX-2 and aromatase expression were measured in both eutopic endometrium and adenomyotic foci using immunohistochemical methods. RESULTS: Aromatase expression was detected in 80% of the endometrial slices by immunohistochemistry. In positive cases, aromatase was mainly detected in the stromal cells of the eutopic endometrium, whereas in the adenomyotic foci this expression was negative in the majority of the cases. Oral contraceptives containing gestodene, on the other hand, were effective in suppressing aromatase expression in both eutopic and ectopic endometrium. COX-2 expression was detected by immunohistochemistry in the glandular epithelium of both eutopic endometrium and adenomyotic foci and there were no significant changes in its intensity throughout the menstrual cycle. CONCLUSION: Aromatase expression in the eutopic endometrium and adenomyotic foci is suppressed by oral contraceptives containing gestodene. Increased aromatase activity may be responsible for the persistent COX-2 expression during the luteal phase.  相似文献   
8.
9.
Ureteral herniation is a rare entity. We report the first case of extraperitoneal ureteral herniation in a pediatric en bloc renal graft causing obstructive uropathy. A 70-year-old, obese patient with an en bloc renal transplant was found to have ureterohydronephrosis in the right renal graft on magnetic resonance imaging. Nephrostomy with insertion of a double-J catheter confirmed the presence of a ureteral loop within the inguinal tract. Surgery confirmed herniation of the ureter through the internal inguinal ring, crossing over the spermatic cord. We performed release, resection, ureteral reimplantation and hernioplasty. Four months later, renal function was normal and urinary tract dilation had diminished. This case illustrates an unusual cause of obstructive uropathy in a transplanted kidney. Apart from obesity, two other factors may have contributed to its development: presence of a redundant ureter, and the fact that the ureter had been placed over, rather than under, the spermatic cord.  相似文献   
10.
Background contextLarge, prominent osteophytes along the anterior aspect of the cervical spine have been reported as a cause of dysphagia. Improvement of swallowing after surgical resection has been reported in a few case reports with short-term follow-up. The current report describes outcomes of a series of five patients with surgical treatment for this rare disorder, with a long-term follow-up.PurposeTo study the clinical and radiographic outcomes of a case series of patients surgically treated for dysphagia secondary to cervical diffuse idiopathic skeletal hyperostosis (DISH).Study designRetrospective review of a case series.Patient sampleFive cases from a University Hospital.Outcome measuresClinical and imagenological follow-up.MethodsThe records of five patients with dysphagia who had undergone anterior surgical resection of prominent osteophytes secondary to DISH were reviewed. Extrinsic esophageal compression secondary to anterior cervical osteophytes was radiographically confirmed via preoperative barium esophagogram swallowing study. All patients underwent anterior cervical osteophytes resection without fusion. Postoperatively, patients were followed-up clinically and radiographically with routine lateral cervical radiographs.ResultsPreoperative esophagogram showed that the esophageal obstruction was present at one level in three cases and two levels in two cases. The C3–C4 level was involved in three cases, C4–C5 in three cases, and C5–C6 in one case. There were no postoperative complications, including recurrent laryngeal nerve palsy, wound infection, or hematomas. All patients had resolution of dyphagia soon after surgery (within 2 weeks). Postoperative radiographs demonstrated complete removal of osteophytes. At final follow-up, ranging from 1 to 9 years (average 59.8 months, median 53 months), no patients reported recurrence of dysphagia. Final radiographic examination demonstrated minimal regrowth of the osteophytes.ConclusionsAlthough rarely indicated, surgical resection of anterior cervical osteophytes from DISH causing dyphagia produces good clinical and radiographical outcomes. After thorough evaluation to rule out other intrinsic or extrinsic causes of swallowing difficulty, surgical treatment of this uncommon condition might be considered.  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