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   6979篇
  免费   482篇
  国内免费   31篇
耳鼻咽喉   56篇
儿科学   198篇
妇产科学   99篇
基础医学   1017篇
口腔科学   128篇
临床医学   595篇
内科学   1339篇
皮肤病学   216篇
神经病学   723篇
特种医学   341篇
外国民族医学   1篇
外科学   1135篇
综合类   33篇
一般理论   5篇
预防医学   485篇
眼科学   90篇
药学   502篇
中国医学   7篇
肿瘤学   522篇
  2023年   75篇
  2022年   137篇
  2021年   226篇
  2020年   160篇
  2019年   208篇
  2018年   242篇
  2017年   197篇
  2016年   210篇
  2015年   244篇
  2014年   278篇
  2013年   357篇
  2012年   552篇
  2011年   534篇
  2010年   332篇
  2009年   300篇
  2008年   428篇
  2007年   387篇
  2006年   399篇
  2005年   333篇
  2004年   260篇
  2003年   266篇
  2002年   218篇
  2001年   125篇
  2000年   100篇
  1999年   96篇
  1998年   73篇
  1997年   54篇
  1996年   41篇
  1995年   25篇
  1994年   21篇
  1993年   16篇
  1992年   52篇
  1991年   52篇
  1990年   30篇
  1989年   46篇
  1988年   29篇
  1987年   29篇
  1986年   29篇
  1985年   30篇
  1984年   14篇
  1983年   16篇
  1982年   15篇
  1980年   11篇
  1979年   24篇
  1978年   16篇
  1977年   18篇
  1976年   19篇
  1974年   11篇
  1971年   12篇
  1967年   11篇
排序方式: 共有7492条查询结果,搜索用时 15 毫秒
1.
2.
Tauchunfälle     
Notfall + Rettungsmedizin - Tauchunfälle sind vergleichsweise selten und stellen (Erst‑)Helfer vor besondere Herausforderungen. Sie müssen schnell und kompetent behandelt werden, da...  相似文献   
3.
Die Gynäkologie - Frauen im Erwachsenenalter mit einem angeborenen Herzfehler (EMAH) werden in Zukunft aufgrund des medizinischen Fortschritts eine immer größere Patientinnengruppe...  相似文献   
4.
BACKGROUND: The problems associated with rectal surgery are frequently discussed with no reference being made to the distance of the tumor from the anal verge. This study examined the effect of the location of the tumor on early postoperative results. PATIENTS AND METHODS: This was a multicenter study involving 75 German hospitals and 3756 patients, of whom 1463 had rectal carcinoma. On the basis of the location of the tumor (distance from the anal verge), four groups were distinguished: <4, 4-7.9, 8-11.9, and 12-16 cm. RESULTS: Resection and abdominoperineal resection rates and the incidence of postoperative complications depended on the location of the tumor. Significantly higher resection rates and fewer specific complications, and a significant reduction in overall postoperative morbidity were found with tumor locations more than 8 cm from the anal verge. The highest anastomotic leak rate was observed with anastomoses less than 7 cm from the anal verge. The logistic regression showed that the distance of the tumor from the anal verge is an independent variable for the development of an anastomotic leak. CONCLUSIONS: Early results are greatly affected by the location of the rectal carcinoma. This applies to both abdominoperineal resection rates and specific postoperative complications, such as anastomotic leak rate and operation morbidity in general.  相似文献   
5.
A novel assay for factor XIII is described that utilizes exclusively small synthetic peptides as substrates for the cross-linking reaction catalyzed by activated factor XIII (FXIIIa). The acyl donor substrate (selection peptide) is immobilized on a microplate via biotin while the acyl acceptor substrate (detection peptide) is labeled with the fluorochrome Oregon green to allow sensitive detection without the need for secondary enzyme systems for signal amplification. Starting with an amino acid sequence from the fibrin gamma-chain (GQQHHLGGAKQAGDV) as a prototype peptide, the influence of amino acid exchanges were investigated with respect to their impact on the FXIIIa-catalyzed reaction. It was found that FXIIIa readily accepts a broad range of substrate peptides, with a proline neighboring the essential lysine having the most detrimental effect. The assay appears to be valuable for the molecular characterization of factor XIII and may be used for a deeper investigation into the substrate requirements of this final enzyme of wound repair, and eventually also for the characterization of other transglutaminases.  相似文献   
6.
It obviously escaped the notion of Egeland and Brinchman thatthe protocols additionally differ with regard to the washingsteps and buffer components used in the  相似文献   
7.
8.
OBJECTIVE: To analyse the image quality and diagnostic effectiveness of a new C-arm-based 3D imaging method (C-arm-CT) for intraoperative evaluation of screw osteosyntheses adjacent to a peripheral joint. MATERIALS AND METHODS: Insertion of screws into four cadaveric specimens simulated the surgical treatment of talus neck fractures. Ten orthopedic surgeons and 10 radiologists evaluated X-ray, C-arm fluoroscopy, C-arm-CT and CT images. RESULTS: The best image quality was obtained with X-rays (p < 0.001), followed by C-arm fluoroscopy (2D) and CT, with the C-arm-CT (3D) being rated lowest (p < 0.001). The most correct diagnoses were obtained with CT and C-arm-CT (with no statistical difference between them), while C-arm-fluoroscopy was inferior (p < 0.001) and X-rays were the worst (p < 0.05). CONCLUSIONS: Even if the image quality of C-arm-CT is definitely inferior to that of CT, screw misplacements can be reliably detected using C-arm-CT. As compared to the current standard procedures (intraoperative fluoroscopy and postoperative radiography), C-arm-CT performed better. C-arm-CT is ideally suited to the intraoperative diagnosis of high-contrast inquiries like bone fragments and OS material, especially at the extremities. Coupling of the new 3D imaging to existing navigation systems is possible. C-arm-CT will support the further development and implementation of open and minimally invasive surgical procedures.  相似文献   
9.
OBJECTIVE: Prospectively to compare lymphatic drainage after ultrasonic dissection, an electrocoagulation technique and sharp dissection in the groin during surgery for recurrent sapheno-femoral incompetence. DESIGN: Prospective, randomised study comparing three surgical techniques. METHODS: Thirty-six consecutive patients undergoing surgery for recurrent sapheno-femoral incompetence were randomised. Twelve patients underwent dissection with ultrasound, 12 with electrocoagulation and 12 controls had sharp dissection with ligation of scar and lymphatic tissue using absorbable suture material. RESULTS: The mean drain output per patient was 13.5 ml in the ultrasonic group, 15.4 ml in the electrocoagulation group and 8.3 ml in the suture ligation group. Six minor cases of lymphatic leakage occurred in the ultrasonic group. This resulted in no clinical problem. There were no other significant differences between the three groups. CONCLUSIONS: There is no detectable advantage for the use of ultrasound or electrocoagulation in recurrent saphenous high ligation compared to sharp dissection.  相似文献   
10.
An operative technique modified after Viernstein and Kelly for the treatment of chronic, recurrent peronal tendon dislocation is presented, which has been performed successfully in 15 cases. Principal elements of this technique are an improvement of the bony containment of the tendons within the shallowed, malleolar sulcus and the use of the outer layer of the dislocation pouch as superior retinaculum. This is achieved by inserting the outer layer underneath a dorsally displaced, bony lamella of the outer malleolus.  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