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   49341篇
  免费   2992篇
  国内免费   245篇
耳鼻咽喉   501篇
儿科学   925篇
妇产科学   628篇
基础医学   6451篇
口腔科学   1095篇
临床医学   5177篇
内科学   10830篇
皮肤病学   986篇
神经病学   5638篇
特种医学   2503篇
外科学   8343篇
综合类   297篇
一般理论   14篇
预防医学   2263篇
眼科学   658篇
药学   2943篇
中国医学   73篇
肿瘤学   3253篇
  2024年   49篇
  2023年   438篇
  2022年   703篇
  2021年   1419篇
  2020年   850篇
  2019年   1279篇
  2018年   1439篇
  2017年   1132篇
  2016年   1349篇
  2015年   1560篇
  2014年   1980篇
  2013年   2434篇
  2012年   3912篇
  2011年   3945篇
  2010年   2346篇
  2009年   2119篇
  2008年   3351篇
  2007年   3441篇
  2006年   3179篇
  2005年   3133篇
  2004年   2768篇
  2003年   2644篇
  2002年   2389篇
  2001年   441篇
  2000年   335篇
  1999年   401篇
  1998年   479篇
  1997年   370篇
  1996年   286篇
  1995年   222篇
  1994年   219篇
  1993年   164篇
  1992年   141篇
  1991年   130篇
  1990年   97篇
  1989年   89篇
  1988年   94篇
  1987年   60篇
  1986年   72篇
  1985年   69篇
  1984年   102篇
  1983年   80篇
  1982年   75篇
  1981年   57篇
  1980年   56篇
  1979年   52篇
  1978年   48篇
  1977年   50篇
  1975年   48篇
  1974年   50篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.

Purpose

The purpose of this study was to evaluate the clinical and radiological outcome following compression plate fixation in combination with autologous bone grafting, with and without additional application of recombinant human bone morphogenetic protein (rhBMP) for treatment of aseptic clavicle non-union.

Methods

Between April 2004 and April 2015, 82 patients were treated for clavicle fracture and had developed aseptic clavicle non-union. Seventy-three out of 82 patients were available for follow-up at least one year after revision surgery; among them, 27 women and 46 men, with a median age of 49 (range, 19–86) years. Forty-five patients received compression plate osteosynthesis with autologous bone grafting, and 28 patients obtained compression plate fixation with autologous bone grafting and additional application of rhBMP-2 (3/28 patients) or rhBMP-7 (25/28 patients).

Results

Seventy out of 73 non-unions (96 %) healed within 12 months after revision surgery. Functional outcome according to the DASH Outcome Measure (with rhBMP, 33.16 ± 1.17 points; without rhBMP, 30.58 ± 2.12 points [mean ± SEM]; p?=?0.81), non-union healing (p?=?0.86), time interval between revision surgery and bone healing (p?=?0.37), as well as post-operative complications, did not demonstrate relevant differences between the treatment groups and were not age-dependent.

Discussion

Functional and radiological results demonstrate that successful healing of aseptic clavicle non-union is dependent on radical resection of non-union tissue, restoration of length of the shoulder girdle and application of stable locking-plate osteosynthesis in combination with autologous bone grafting, but not dependent on application of additional rhBMP.
  相似文献   
992.

Background

Excision repair cross-complementing 1 (ERCC1) has been associated with outcomes of urothelial carcinoma of the bladder, but was not yet studied in upper tract urothelial carcinoma (UTUC). The aim of this study was to assess the prognostic role of ERCC1 expression in a large international cohort of UTUC patients.

Methods

Immunohistochemical ERCC1 expression was evaluated in 716 UTUC patients who underwent radical nephroureterectomy with curative intent. ERCC1 was considered positive when the H-score was >1.0. Associations with overall survival and cancer-specific survival were assessed using univariable and multivariable Cox models.

Results

ERCC1 was expressed in 303 tumors (42.3 %) and linked with the presence of tumor necrosis (16.2 vs. 10.4 %, p = 0.023), but not with any other clinical or pathological variable. ERCC1 status did not predict cancer-specific survival and overall survival on both univariable (p = 0.70 and 0.32, respectively) and multivariable analyses (p = 0.48 and 0.33, respectively).

Conclusions

ERCC1 is expressed in a significant proportion of UTUC and is linked with tumor necrosis, but its expression appears not to be associated with prognosis following radical nephroureterectomy.
  相似文献   
993.
994.
995.
996.
997.
998.

Purpose

Hirschsprung’s disease-associated enterocolitis (HAEC) is the most common cause of morbidity and mortality in Hirschsprung’s disease (HSCR). Altered intestinal epithelial barrier function is implicated in the pathogenesis of HAEC. IL-17 is a proinflammatory cytokine that plays a crucial role in host defense against microbial organisms in the development of inflammatory diseases. Act1 is an essential adaptor molecule required for the IL-17-mediated inflammatory responses via interaction with IL-17 receptor (IL-17R). We designed this study to investigate the hypothesis that Act1/Il-17R expression is upregulated in HSCR.

Methods

We investigated Act1 and IL17R expression in ganglionic andaganglionic bowel of HD patients (n = 10) and controls (n = 10). qPCR, Western blotting and confocal immunofluorescence were performed.

Main results

qPCR and Western blot analysis revealed that Act1 and IL17R are strongly expressed in the aganglionic and ganglionic colon of patients with HSCR. Act1 and IL17R expression was significantly increased in HSCR specimens compared to controls (p < 0.05). Confocal microscopy revealed a markedly increased expression of Act1 and IL17R in the colonic epithelium of patients with HSCR compared to controls.

Conclusion

To our knowledge, we report, for the first time, the expression of Act1 in the human colon. The increased expression of Act1 and Il-17 in the aganglionic and ganglionic bowel in HSCR may result in IL-17-mediated increased inflammatory response leading to the development of HAEC
  相似文献   
999.
Conclusions The recurrence rate of IP in the current study is comparable to international and national studies. When the primary tumour was located in the frontal or the sphenoid sinus, the tumour seemed more likely to recur. Some recurrences were more than 2 years after primary surgery, suggesting continued need for long-term follow-up. The rate of malignant transformation in inverted papilloma cases has not changed in Denmark.

Objectives Inverted papillomas are benign tumours located in the nasal cavity and paranasal sinuses. They are known for their tendency to recur after surgery and show invasive growth, causing bone remodulation and the association with malignant transformation. The introduction of endoscopic sinus surgery and computer aided sinus surgery over the last decades has made this tumour more approachable with less cosmetic and functional damage. The objective of this study is to establish whether the recurrence rate and the rate of malignant transformation of IP have changed with the application of these new techniques.

Method A retrospective study between 1998–2008 including 88 cases with inverted papilloma.

Results In total, 25.3% had recurrence. Combined surgical approach with endoscope/open approach had the lowest rate of recurrence. A malignant transformation in the postoperative histological examination was found in 8.9%.  相似文献   

1000.
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