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   1067篇
  免费   43篇
  国内免费   54篇
耳鼻咽喉   12篇
儿科学   13篇
妇产科学   2篇
基础医学   17篇
口腔科学   2篇
临床医学   74篇
内科学   253篇
皮肤病学   3篇
神经病学   4篇
特种医学   27篇
外科学   419篇
综合类   126篇
预防医学   31篇
眼科学   1篇
药学   69篇
  1篇
中国医学   2篇
肿瘤学   108篇
  2024年   3篇
  2023年   20篇
  2022年   49篇
  2021年   49篇
  2020年   56篇
  2019年   38篇
  2018年   46篇
  2017年   26篇
  2016年   34篇
  2015年   44篇
  2014年   79篇
  2013年   66篇
  2012年   50篇
  2011年   69篇
  2010年   55篇
  2009年   59篇
  2008年   71篇
  2007年   65篇
  2006年   32篇
  2005年   37篇
  2004年   23篇
  2003年   20篇
  2002年   16篇
  2001年   23篇
  2000年   15篇
  1999年   16篇
  1998年   13篇
  1997年   13篇
  1996年   8篇
  1995年   9篇
  1994年   6篇
  1993年   11篇
  1992年   11篇
  1991年   7篇
  1990年   5篇
  1989年   4篇
  1988年   4篇
  1987年   3篇
  1986年   2篇
  1985年   2篇
  1984年   4篇
  1981年   1篇
排序方式: 共有1164条查询结果,搜索用时 0 毫秒
21.
IntroductionParavalvular leak (PVL) is a common serious complication associated with prosthetic valve implantation.ObjectiveThe aim of this study was to report our single-center experience in a retrospective review and to analyze possible predictors of success.MethodsWe performed 33 percutaneous PVL closures in 26 patients (54% female, mean age 65±13 years). All mitral prostheses were studied previously with 3D transesophageal echocardiography (TEE), and aortic prostheses with 2D/3D TEE. 3D TEE and fluoroscopy were used for the assessment, planning, and guidance of the interventions. Twelve patients also underwent computed tomography angiography for better characterization of anatomic details.ResultsEighteen patients (69.2%) were admitted due to heart failure (New York Heart Association [NYHA] III or IV, seven (26.9%) because of heart failure and hemolysis, and one (3.8%) due to hemolysis only. Regarding the leaks, 46.2% were in aortic and 53.8% in mitral prostheses, 88.5% in mechanical and 7.7% in biological prostheses, and 3.8% in transcatheter aortic valve implants. All the aortic patients had severe aortic regurgitation. Furthermore, all mitral patients but one had moderate to severe or severe mitral regurgitation. Closure was successful in 17 patients (65.4%), partially successful in four (15.4%) and unsuccessful in five (19.2%). After the procedure, 69% were in NYHA I-II. Hemolysis worsened in three patients despite successful closure; all required further valvular surgery and two died. Regarding angiographic and echocardiographic procedural success, we analyzed age, gender, type of prosthesis (mechanical or biological), location (aortic or mitral), clinical data, maximum leak diameter, anatomic regurgitant orifice, leak location (anterior, posterior, inferior and lateral for mitral leaks and left, right and non-coronary sinus for aortic leaks), and number of devices (plugs) used for closure. No parameters presented a significant relationship with success excepting previous hemolysis. There was a relationship between clinical improvement and reduction of PVL (p=0.0001). In follow-up, cardiac-related events (new hospital admissions, cardiac valvular surgery, need for transfusion) were more frequent in patients with partially successful or unsuccessful closure (p=0.012). There was a relationship between cardiac-related events and death (p=0.029).ConclusionPercutaneous PVL closure has emerged as an alternative treatment for PVL. Predictors of procedural success are difficult to establish. Survival is related to reduction of regurgitation and improvement in NYHA functional class.  相似文献   
22.
目的探讨原位肝脏移植术后胆瘘的类型、方法选择及不同方式的治疗结果。方法回顾性分析2000年1月—2019年3月于西安交通大学第一附属医院住院治疗的24例肝移植术后胆瘘患者资料。根据是否合并狭窄将胆瘘分为4型。患者均接受内镜或介入治疗,包括经内镜鼻胆管引流术(endoscopic nasobiliary drainage,ENBD)、经内镜胆道内支架放置术(endoscopic retrograde biliary drainage,ERBD)或经皮经肝胆道引流术(percuteneous transhepatic cholangial drainage,PTCD)。观察指标为胆瘘发现时间、胆瘘位置、 经内镜逆行胰胆管造影术(endoscopic retrograde cholangiopancreatography,ERCP)及PTCD并发症、腹腔或胆道引流管拔出时间、新发胆道狭窄等。结果24例胆瘘于肝移植术后(46.5±36.6) d(6~122 d)发现。Ⅰ~Ⅳ型胆瘘分别有6例、14例、2例和2例。22例胆瘘治愈,总体治愈率91.7%。24例均首先接受ERCP,技术成功率及治愈率分别为87.5%(21/24)和85.7%(18/21)。Ⅰ~Ⅳ型胆瘘ERCP的治愈率分别为6/6、84.6%(11/13)、1/2和0,ENBD与ERBD的胆瘘治愈比列分别为8/10和6/8。5例ERCP未成功者接受PTCD治疗,成功及临床治愈比例分别为4/5和3/4。术后胆道感染发生率为33.3%(8/24),Ⅱ型胆瘘胆管炎发生率高于Ⅰ型 [35.7%(5/14)比16.7%(1/6)],合并非吻合口狭窄者比合并吻合口狭窄者更易发生胆管炎[83.3%(5/6)比16.7%(3/18)]。结论原位肝移植术后胆瘘首选ERCP,次选PTCD。Ⅰ~Ⅳ型胆瘘分别优选ENBD、ENBD联合ERBD、ENBD及PTCD治疗。  相似文献   
23.
24.
Anastomotic recurrence after sphincter-saving resection for rectal cancer   总被引:8,自引:0,他引:8  
A retrospective study of anastomotic recurrence after sphincter-saving resection for rectal cancer is presented. During the 21 years from 1962 to 1982, 273 patients with rectal cancer underwent sphincter-saving resection and 30 (11 percent) of them had anastomotic recurrences. Computer analysis of 69 variables was undertaken to identify factors contributing to the anastomotic recurrence, with special reference to the length of distal clearance of the bowel. There was no significant correlation between the incidence of recurrence and the length of distal clearance of the bowel, if the latter was over 2 cm. There appears to be justification for carrying out a curative sphincter-saving operation for cases in which more than a 2-cm distal margin can be afforded. However, for cancers of the infiltrating type, annular growths, invasion to adjacent organs or mucinous features, a more extensive distal clearance of the bowel is necessary, and the Miles operation should be performed.  相似文献   
25.
Purpose  After restorative proctocolectomy, 7 to 8 percent of patients may have a pouch leak. Concern exists that pouch leak may be associated with impaired functional outcome. We evaluated patients who underwent restorative proctocolectomy to determine whether pouch leak adversely affected long-term functional outcome and quality of life. Methods  We queried our prospectively maintained database of patients who underwent restorative proctocolectomy for demographic and clinical data. We sent a long-term outcome questionnaire to patients, including the validated Fecal Incontinence Severity Index and Cleveland Global Quality of Life scores. Pouch leak was identified by clinical or radiographic evidence of leak. Patients with leak were compared with those without to determine the impact on long-term functional outcome or quality of life. Results  A total of 817 patients were available for follow-up and 374 patients (46 percent) completed questionnaires. The group with (n = 60; 16 percent) and without (n = 314; 84 percent) leak had similar demographics. The median Fecal Incontinence Severity Index score (15.3 vs. 14.7, P = 0.77), Cleveland Global Quality of Life score (0.79 vs. 0.81, P = 0.48), and bowel movements per 24 hours (7.92 vs. 7.88, P = 0.92) were similar. The pouch loss/permanent ileostomy rate was higher in those who leaked (13.3 vs. 0.9 percent, P < 0.001). Conclusions  Anastomotic leak after restorative proctocolectomy does not adversely affect long-term quality of life or functional outcome. However, pouch loss/permanent ileostomy is significantly more likely in patients who have had an anastomotic leak. Read at the meeting of The American Society of Colon and Rectal Surgeons, Boston, Massachusetts, June 7 to 11, 2008. Reprints are not available.  相似文献   
26.
BACKGROUND: Experimental studies on healing of colonic anastomosis have been thoroughly investigated. However, clinical parameters of the healing process of anastomosis in the inflamed colon has not yet been reported. METHODS: In the present study, healing of anastomosis in trinitrobenzene-sulfonic acid-induced colitis in rats was assessed by measuring the bursting pressure and bursting wall tension. RESULTS: On postoperative day 4, bursting pressure and bursting wall tension were significantly lower (P<0.001) in rats with colitis with or without anastomosis and normal colon with anastomosis, compared with normal colon without anastomosis. On postoperative day 7, bursting pressure and bursting wall tension of normal colon with anastomosis approached that of normal colon without anastomosis. However, bursting pressure and bursting wall tension of rats with colitis with or without anastomosis remained significantly lower (P<0.001) than the latter. Furthermore, unlike rats without colitis in which perforation occurred mostly at the anastomotic line, the bursting site in colitic rats was predominantly away from the anastomotic line. CONCLUSIONS: These results suggest that in surgery for inflammatory bowel disease, it is the adjoining inflamed bowel wall that is vulnerable to be perforated in response to increasing intraluminal pressure rather than the anastomosis that is braced by the sutures.  相似文献   
27.
Animal studies have demonstrated the value of the proteolytic enzyme inhibitor, aprotinin, in reducing collagen breakdown and improving the healing of experimental colonic anastomoses. A double-blind, multicenter, prospective trial has evaluated the use of aprotinin in the prevention of anastomic leakage in patients. Two hundred sixteen patients undergoing colonic resection and anastomosis were studied. Patients were randomized to receive either aprotinin or placebo intravenously, peroperatively, and for the first three postoperative days. Anastomotic integrity was assessed clinically and by Hypaque® enema on the tenth postoperative day. Although the use of aprotinin was not associated with a significant overall decrease in anastomotic leakage rates, in 95 patients undergoing anterior resection, leakage rates in those receiving aprotinin (clinical 10.8 percent; radiologic 32.4 percent) were lower than in those receiving placebo (17.2 percent and 43.1 percent, respectively). An apparent adverse association was noted, however, in patients undergoing left hemicolectomy or sigmoid colectomy who received aprotinin.  相似文献   
28.

Background:

Anastomotic leak is a serious complication after major gastrointestinal surgery and majority of deaths occur due to septic shock. Therefore, the early identification of risk factors of septic shock may help reduce the adverse outcomes.

Objective:

The aim of this audit was to determine the predictors of septic shock in patients with anastomotic leak after major gastrointestinal surgery.

Design:

Retrospective, audit.

Materials and Methods:

The patients admitted in the gastrosurgical intensive care unit ICU) of our institute between September 2009 and April 2012 with anastomotic leakage after surgery were identified. The ICU charts were retrieved from the database to identify the patients progressing to septic shock. A comparison of risk factors was made between the patients who developed septic shock (septic shock group) against the patients who did not (non-septic shock group).

Results:

The study sample comprised of 103 patients with anastomotic leak, of which 72 patients developed septic shock. The septic shock group had a higher APACHE II score, lower MAP, and higher HR at the time of ICU admission. They received greater transfusion of packed red blood cells during their ICU stay. Septic shock was more common after pancreaticojejunostomy and hepaticojejunostomy leaks.

Conclusion:

Presence of malignancy, chronic obstructive pulmonary disease (COPD), packed red blood cell transfusion, bacteremia, and hepaticojejunostomy or pancreaticojejunostomy leaks were independent predictors of mortality and length of ICU stay. To the best of our knowledge there are no available studies in the literature on the predictors of risk factors of septic shock in patients with anastomotic leakage.  相似文献   
29.
Purpose Because of the relatively high morbidity and mortality of anastomotic leakage in patients with low rectal cancer who receive an anterior resection, many fecal diverting methods have been introduced. This study was designed to assess the efficacy and safety of the Valtrac™-secured intracolonic bypass in protecting low rectal anastomosis and to compare the efficacy and complications of Valtrac™-secured intracolonic bypass with those of loop ileostomy. Methods From January 2002 to April 2006, 83 patients with rectal cancer who underwent elective low anterior resection received intracolonic bypass or ileostomy. Demographics, clinical features, and operative data were recorded. Results Forty-four patients (53 percent) received a Valtrac™-secured intracolonic bypass and 39 patients (47 percent) a loop ileostomy. The demographics and clinical features of the groups were similar. None of the patients developed clinical anastomotic leakage. Longer overall postoperative hospital stay (21.3 ± 5.8 days) and higher costs incurred (3.1 ± 0.9 × $1,000 U.S. dollars) were observed in the ileostomy group than in the intracolonic bypass group (12.5 ± 6.3 days, 4.4 ± 1.2 × $1,000 U.S. dollars; P < 0.05). Stoma-related complications in the ileostomy group included dermatitis (12.8 percent), bleeding (2.6 percent), and intestinal obstruction after stoma closure (5.1 percent). No complications were observed in the intracolonic bypass group except for the Valtrac™ ring discharging en bloc, which compromised fecal evacuation in two cases (4.5 percent). Conclusions The Valtrac™-secured intracolonic bypass procedure is a safe, effective, but time-limited, diverting technique to protect an elective low colorectal anastomosis. Valtrac™-secured intracolonic bypass, in contrast to loop ileostomy, avoids stoma-related complications or readmission for closure and is associated with decreased hospital time and cost. Presented at the First National Conference on Colorectal Surgery, Zhu Hai, Guang Dong, China, November 2 to 5, 2006. Reprints are not available.  相似文献   
30.
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