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   7409篇
  免费   372篇
  国内免费   91篇
耳鼻咽喉   57篇
儿科学   190篇
妇产科学   164篇
基础医学   884篇
口腔科学   143篇
临床医学   544篇
内科学   2022篇
皮肤病学   218篇
神经病学   746篇
特种医学   281篇
外科学   1222篇
综合类   21篇
预防医学   335篇
眼科学   68篇
药学   393篇
中国医学   7篇
肿瘤学   577篇
  2024年   10篇
  2023年   74篇
  2022年   153篇
  2021年   255篇
  2020年   140篇
  2019年   176篇
  2018年   214篇
  2017年   156篇
  2016年   206篇
  2015年   234篇
  2014年   290篇
  2013年   380篇
  2012年   555篇
  2011年   586篇
  2010年   331篇
  2009年   308篇
  2008年   472篇
  2007年   464篇
  2006年   469篇
  2005年   471篇
  2004年   428篇
  2003年   376篇
  2002年   316篇
  2001年   54篇
  2000年   44篇
  1999年   51篇
  1998年   55篇
  1997年   57篇
  1996年   42篇
  1995年   42篇
  1994年   37篇
  1993年   33篇
  1992年   23篇
  1991年   24篇
  1990年   28篇
  1989年   23篇
  1988年   25篇
  1987年   28篇
  1986年   24篇
  1985年   28篇
  1984年   22篇
  1983年   17篇
  1982年   16篇
  1981年   11篇
  1980年   9篇
  1979年   14篇
  1977年   6篇
  1976年   8篇
  1974年   9篇
  1964年   6篇
排序方式: 共有7872条查询结果,搜索用时 15 毫秒
51.
52.
Arterial-venous extracorporeal membrane oxygenation (ECMO) is more and more used as first line mechanical support in acute cardiopulmonary failure. Important pitfall of this technique is the inappropriate unloading of left ventricle (LV) in case of myocardial insufficiency, leading to pulmonary stasis and inadequate myocardial recovery. We report our experience of left side unloading by a 7-F pigtail, introduced in the LV through the aortic valve, connected to the venous drainage. Echographic guidance is sufficient to pigtail positioning and follow-up monitoring avoiding catheterization laboratory transport. With this approach we were able to support three different patients, resolving LV distension and preventing lung congestion, without major complication.  相似文献   
53.

Background  

While laparoscopic Roux-en-Y gastric bypass is one of the most commonly performed procedures for morbid obesity in the USA, robotic application has been viewed as a valid option. However, the technique is not firmly established with single robotic docking. The objective of this video is to demonstrate the technical details of performing a standardized monoquadrant robotic Roux-en-Y gastric bypass (RRYGB).  相似文献   
54.

INTRODUCTION

Small bowel injuries after blunt abdominal trauma represent both a diagnostic and a therapeutic challenge. Early diagnosis and prompt treatment are necessary in order to avoid a dangerous diagnostic delay. Laparoscopy can represent a diagnostic and therapeutic tool in patients with uncertain clinical symptoms.

PRESENTATION OF THE CASE

We report the case of a 25-year-old man, haemodynamically stable, admitted for acute abdominal pain a few hours after a physical assault. Giving the persistence of the abdominal pain and the presence of free fluids at the computed tomography examination, an exploratory laparoscopy was performed.

DISCUSSION

At the laparoscopic exploration, an isolated small bowel perforation was found, 60 cm distal from the ligament of Treitz. The injury was repaired by laparoscopic suturing and the patient was discharged home at postoperative day 3 after an uneventful postoperative course.

CONCLUSIONS

Laparoscopy represents a valuable tool for patients with small bowel blunt injuries allowing a timely diagnosis and a prompt treatment.  相似文献   
55.
Background Although the feasibility of laparoscopic resection of gastric gastrointestinal stromal tumors (GISTs) has been established, various aspects are debated. This paper describes the problems of minimally invasive resection of gastric GISTs and compares this experience with an extensive literature review. Study Design Between August 2001 and December 2006, 21 consecutive patients undergoing laparoscopic resection of gastric GISTs were enrolled in a prospective study. A literature review of laparoscopic treatment was performed on Pubmed using keywords GIST and surgery. A comparison with authors’ experience with open wedge-segmental resection of GISTs (25 cases from November 1995 to December 2000) was also carried out. Statistical analysis was based on chi-squared test and t Student evaluation. Results Twenty-one patients, mean age 50.1 years (range, 34–68 years), were submitted to laparoscopic wedge- segmental gastric resections. Mean tumor size was 4.5 cm (range, 2.0–8.5 cm). Mean operative time was 151 min (range, 52–310 min), the mean blood loss was 101 mL (range, 10–250 mL), and the mean hospital stay was 4.8 days (range 3–7 days). There were no major operative complications or mortalities. All lesions had negative resection margins. At a mean follow-up of 35 months, all patients were disease-free. Morbidity, mortality, length of stay, and oncologic outcomes were comparable to the open surgery retrospective evaluation (p = not significant). Conclusions As found also in the literature review, the laparoscopic resection is safe and effective in treating gastric GISTs. Given these findings as well as the advantages afforded by laparoscopic surgery, a minimally invasive approach should be the preferred surgical treatment in patients with small- and medium-sized gastric GISTs.  相似文献   
56.
The gold standard procedure for the evaluation of vesicoureteral reflux (VUR) is the radiographic voiding cystourethrography (VCUG); direct radionuclide voiding cystography (DRVC) is an alternative method for detecting VUR. A new imaging procedure, voiding urosonography (VUS) with contrast medium, has recently been introduced. We have carried out a comparative study of these three techniques in 157 patients (aged 6 weeks–4.7 years). VUS showed the presence of VUR in 91 of 311 renal units; VCUG detected reflux in 64 of 233 renal units, and the DRVC in 23 of 78 renal units. VCUG and VUS were compared in 118 patients, and both procedures showed the same grade of reflux in 56 refluxing units (kappa value 0.92); in six cases the reflux grade was greater at VUS than at VCUG. Seven cases of reflux detected by VUS were not identified on VCUG. VCUG did not show a grade of VUR that was higher than in VUS in any patient. In the identification of 4°–5° grade reflux, the sensitivity of VUS reached 100%. VUS and DRVC were found to be equally effective in the detection of VUR (kappa value 0.85). In conclusion, we found that VUS is a useful method for the diagnosis and grading of patients with VUR.  相似文献   
57.
A 16-year-old girl complained of 2-year history of right facial pain, episodic vertigo and progressive hearing loss in the right ear. The facial pain was described as an episodic lancinating event confined to the second and third branch of the right trigeminal nerve. Computed tomography and magnetic resonance imaging revealed a 2 cm lesion in the right cerebellopontine-angle. At surgery, a soft, yellowish mass was found incorporating the 7th and 8th cranial nerves. The anterior-inferior cerebellar artery (AICA) was displaced medially and pushed into the sensory portion of the trigeminal nerve root, causing vascular compression. The hearing loss remained unchanged. The trigeminal pain disappeared over a period of several weeks. Patients can be harmed in an attempt to remove these neurovascular nonmalignant, generally non growing, fatty vascular lumps. Only a partial, meticulous removal should be performed with a maximum effort to decompress the affected nerve.  相似文献   
58.
In 10 patients having deep infection after total hip replacement, we used a two-stage revision procedure involving implantation of a preformed spacer with a cylindrical rod coated with acrylic cement containing antibiotics (Spacer-G). This device, which remained in situ for an average of 5 months, permitted healing of the infection in 8 cases and reimplantation of a new prosthesis (mean follow-up 35 months). During treatment, 1 dislocation occurred. The spacer maintained the gap between both bone segments and allowed a certain degree of joint mobility. Use of Spacer-G improved the quality of life of the patients during treatment and accelerated recovery of function after reimplantation.  相似文献   
59.
PURPOSE: The aim of this study was to analyze the results from laparotomic and laparoscopic Duhamel pull-through in the treatment of Hirschsprung disease. MATERIALS AND METHODS: In our department, the Duhamel pull-through technique was adopted in most patients and the laparoscopic technique used since 1999 follows the original Duhamel procedure. Patients were identified retrospectively and followed up in our outpatient clinic. Preoperative, operative, and postoperative data were collected and analyzed. RESULTS: Between January 1992 and March 1999, 21 children with Hirschsprung disease underwent primary surgical correction using the classic open Duhamel pull-through. The mean age at operation was 14 months, the median operating time was 297 minutes, and the average postoperative stay was 10 days. From April 1999 to December 2003, 22 children underwent laparoscopic Duhamel pull-through. The mean age at operation was 14.6 months, the mean operative time was 253 minutes, and the mean postoperative stay was 6.8 days. The rates of early (4.7% vs. 4.7%) and late (19% vs. 23.8%) complications were similar in the two groups, but in the laparoscopic group the mean operative time and postoperative hospital stay were lower. CONCLUSION: With these encouraging results, laparoscopic Duhamel pull-through has become our procedure of choice in the surgical management of Hirschsprung's disease.  相似文献   
60.
Faecal incontinence caused by a weak or disrupted internal anal sphincter is common and the efficacy of current treatments for this condition is poor. This study evaluated the short- and long-term effects of injections of silicone biomaterials (PTQ) commonly used to increase anal internal sphincter resistance. A total of 16 patients with a mean age of 66 years affected by faecal incontinence with a low anal resistance to the pressure due to previous surgery of the pelvic region were submitted to intra-sphincteric PTQ injections. The effects of the treatment on the symptoms associated with faecal incontinence and on quality of life were evaluated with the American Medical System Score and with anal ultrasound at 3 months and one year after the procedures in comparison with the scores calculated at entry. At 3 months from the procedure, anal ultrasound confirmed that PTQ injections had been correctly performed without material migration to other regions. Faecal continence was significantly improved but more efficacy was found one year after the injections. The American Medical System Score calculated one year after the procedures was significantly improved in comparison with the scores calculated at entry. During the follow-up the Authors did not observe any significant complications. PTQ injections significantly improved faecal continence and consequently the quality of life of patients with sphincter dysfunctions.  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