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   170407篇
  免费   6694篇
  国内免费   376篇
耳鼻咽喉   2290篇
儿科学   4929篇
妇产科学   3940篇
基础医学   24567篇
口腔科学   5523篇
临床医学   9861篇
内科学   37302篇
皮肤病学   4812篇
神经病学   13735篇
特种医学   4236篇
外国民族医学   1篇
外科学   19743篇
综合类   817篇
一般理论   29篇
预防医学   20112篇
眼科学   4503篇
药学   13419篇
中国医学   695篇
肿瘤学   6963篇
  2023年   889篇
  2022年   660篇
  2021年   2636篇
  2020年   1511篇
  2019年   3002篇
  2018年   5228篇
  2017年   3268篇
  2016年   3314篇
  2015年   3659篇
  2014年   4106篇
  2013年   6180篇
  2012年   10656篇
  2011年   11278篇
  2010年   5599篇
  2009年   4013篇
  2008年   8952篇
  2007年   9563篇
  2006年   9182篇
  2005年   8797篇
  2004年   8142篇
  2003年   7635篇
  2002年   7257篇
  2001年   4972篇
  2000年   5513篇
  1999年   4197篇
  1998年   771篇
  1992年   2262篇
  1991年   2020篇
  1990年   2009篇
  1989年   1710篇
  1988年   1633篇
  1987年   1530篇
  1986年   1575篇
  1985年   1493篇
  1984年   1069篇
  1983年   923篇
  1979年   1237篇
  1978年   825篇
  1977年   806篇
  1976年   760篇
  1975年   903篇
  1974年   1133篇
  1973年   1192篇
  1972年   1129篇
  1971年   1087篇
  1970年   1018篇
  1969年   1095篇
  1968年   1112篇
  1967年   993篇
  1966年   886篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
981.
1. Authors present an "old-new" main bronchus closure procedure, which combines the Sweet's and Overholt's methods, recommended by Asamura-Naruke. 2. The A-N procedure decreased the prevalence of BPF from 2.8% to 0.09% in case of thoracotomy and from 9.5% to 2.4% in case of pneumonectomy compared 2 different stump-closing types. 3. There was not BPF in the "covered subgroup" (0%/92 PN) recommended by us, independent of the closing types. 4. All bronchial stumps closed like A-N and covered by our method (0% BPF/62 PN) healed.  相似文献   
982.
Gastro-esophageal reflux disease is regarded as the single most common foregut disorder mainly in Western countries. The pathophysiological background of the disease is multifactorial. The primary aim of the management of gastro-esophageal reflux disease is relieving heartburn and healing esophagitis. The therapeutic objectives are alleviating symptoms, preventing complications and avoiding recurrence. Besides the effective medical treatment nowadays we possess the minimal invasive anti-reflux surgery which gives comparable, even better results than medical therapy does, in cases of patients who are suitable for anti-reflux surgery. The key question is the appropriate patient selection. In order to achieve the most adequate patient selection, diagnostic tools like endoscopy, radiotherapy, esophageal body and sphincter manometry, 24-hour esophageal pH monitoring and occasionally 24-hour bile exposure monitoring and gastric emptying studies are mandatory to carry out preoperatively. On the basis of the results of these tests the tailored concept of anti-reflux surgery can be applied. The importance of experienced surgeon should be pointed out, too.  相似文献   
983.
INTRODUCTION: By the introduction of the laparoscopy for the management of gastric pathology many techniques are applied by now. In these techniques the collaboration of the endoscopist and the laparoscopic surgeon is mandatory. AIMS OF THE STUDY: To emphasise the necessity of the collaboration of the endoscopist and the laparoscopic surgeon for the management of the gastric pathology using the double lifting and wedge resection technique. METHOD: A case of a female with 2 x 2.5 cm submucosal tumour is presented. The tumour was located in the antrum. After the onset of the general anaesthesia the gastroscope was introduced to locate the position of the tumour, the free edges of the tumour were elevated by a double lifting method and the tumour was resected by a laparoscopic linear stapler. The process of the proper resection was all through observed and directed by the view of the gastroscope. CONCLUSION: Correct wedge resection of the gastric wall can be safely performed, if the correct gastroscopic control is present. The collaboration of the endoscopist and the laparoscopic surgeon seems to be mandatory, thus avoiding the hazards arising from the use of tattooing.  相似文献   
984.
Authors report elective diagnostic laparoscopy, and the role of this method in evaluating operability of pancreatic cancer. At their department 11 diagnostic laparoscopic procedures of pancreatic cancer were performed during the last 5 years. In 3 cases tumor proved to be resectable despite preoperative imaging results of unresectable condition. On the basis of international literature authors give brief summary of indications, cost and benefit of diagnostic laparoscopy, and its place in the diagnostic algorythm of pancreatic cancer.  相似文献   
985.
Synchronically performed laparoscopic cholecystectomy and hernioplasty   总被引:2,自引:0,他引:2  
Cholecystectomies and hernioplasties are the two most frequently performed surgical interventions. The laparoscopic technique can be offered for the simultaneous treatment with both operating indications. The synchronical operation can give all the advantages of the minimally invasive technique. Authors had performed laparoscopic cholecystectomy with laparoscopic hernioplasty in five cases. Two inguinal and three postoperative hernias were reconstructed. The cholecystectomy was performed with a "three punction method", and the hernioplasty by using the same approach, completed by inserting a fourth assisting trocar as required. The hernial ring was covered with an intraperitoneally placed mesh, which was fixed by staplers (the so-called "IPOM-method": intraperitoneal on-lay mesh). There was no intra-, nor postoperative complication. The hernioplasty combined with laparoscopic cholecystectomy did not have effect on postoperative pain and nursing time. The return to the normal physical activity was short, similar to laparoscopic hernioplasty (in 1-2 weeks). Authors conclude that the simultaneous, synchronous laparoscopic cholecystectomy and hernioplasty is recommended and should be the method of choice because it is more advantageous for patients.  相似文献   
986.
In inguinal hernia repair, different laparoscopic and open techniques of tension-free repair using synthetic meshes have been reported to result in better patient comfort and lower recurrence rates compared with conventional procedures like Shouldice's or Bassini's operation. In comparison with the laparoscopic procedure, open tension-free repair can be performed under local anaesthesia and is less expensive. For these reasons, the recent trend in inguinal hernia surgery, has been towards using an open, mesh-based tensionless repair (Lichtenstein technique). To evaluate and support the widespread use of this technique in Hungary a large, prospective multicentre trial was initiated at 15 March 1999. Prospective registration of 1500 hernia operation using Lichtenstein technique is undertaken that is carried out in 15 hospitals. Postoperative outcome, complications and recurrence is recorded through a five years period. The case presentation and data collection is internet based. Each center participating in the study is connected by internet to the coordinating center and all information concerning this study is sent by this way. This system is able to generate actual statistical data in every moment of the study.  相似文献   
987.
PURPOSE: This is a retrospective study comparing the clinical data and morbidity of transperitoneal radical nephrectomy (TRN) and simple nephrectomy. MATERIAL AND METHODS: From 1st January, 1989 to 1st January, 1996 a total of 90 simple nephrectomies and from 1st January, 1996 to 1st August, 1999 a number of 85 TRN were performed at the Department of Urology of the Saint Stephen Hospital. The analysis of clinical data included operative time, length of analgesics, postoperative hospital stay and blood loss, as well as morbidity. RESULTS: The mean operative time for TRN was 170 min., being 95 min. for simple nephrectomy. The mean blood loss for TRN was 250 ml, and 400 ml for simple nephrectomy. There were different types of morbidity for TRN and simple nephrectomy. The complications of TRN mean minimal risk and easy correctibility. CONCLUSION: Our results demonstrate an overall clear advantage of TRN when compared to simple nephrectomy.  相似文献   
988.
A concise account of formation mechanisms of attached (papillary) and unattached renal stones is presented. Urinary conditions prevailing at least during the stone forming period are indicated. Ten main categories of renal stones, covering over 95% of all conceivable calculi, are distinguished based on their composition and structure. Aetiologic factors leading to stone formation of every category are specified and general outlines of recommended treatment procedures indicated.  相似文献   
989.
Studies using roentgen stereophotogrammetric analysis (RSA) have shown that the femoral components of cemented total hip replacements (THR) migrate distally relative to the bone, but it is not clear whether this occurs at the cement-implant or the cement-bone interface or within the cement mantle. Our aim was to determine where this migration occurred, since this has important implications for the way in which implants function and fail. Using RSA we compared for two years the migration of the tip of the stem with that of the cement restrictor for two different designs of THR, the Exeter and Charnley Elite. We have assumed that if the cement restrictor migrates, then at least part of the cement mantle also migrates. Our results have shown that the Exeter migrates distally three times faster than the Charnley Elite and at different interfaces. With the Exeter migration was at the cement-implant interface whereas with the Charnley Elite there was migration at both the cement-bone and the cement-implant interfaces.  相似文献   
990.
OBJECTIVES: To determine conventional computed tomography (CT) signs in the diagnosis and staging of upper urinary tract tumors (UUTTs). METHODS: Retrospective study was made of the CTs of 82 patients diagnosed with UUTTs. Nine CT signs were defined and compared with the pathology of the surgical specimen. A chi2 test was used for statistical analyses. RESULTS: We reviewed the CTs of 93 UUTTs in 82 patients, of which 36% were invasive and 12% had positive lymph nodes. Renal parenchymal invasion was found in 82% of high-grade and in 18% of low-grade tumors (p = 0.001). 94% of the tumors with signs of renal parenchymal invasion were invasive (p < 0.001), as well as 88% of those appearing as renal masses (p = 0.005), with a global sensitivity of 64% and specificity of 97%. The CT sensitivity and specificity of detecting infiltration of the ureter was 67 and 77%, respectively, and no sign was statistically significant. The detection of lymph node involvement had a sensitivity of 87.5% and a specificity of 98%. CONCLUSIONS: CT offers good sensitivity (87.5%) and specificity (98%) in the detection of lymph node involvement, and 64% sensitivity and 97% specificity for the detection of renal tumor invasion.  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