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   159710篇
  免费   10315篇
  国内免费   2070篇
耳鼻咽喉   3257篇
儿科学   1583篇
妇产科学   2047篇
基础医学   3877篇
口腔科学   3632篇
临床医学   44817篇
内科学   11717篇
皮肤病学   1054篇
神经病学   3972篇
特种医学   2273篇
外国民族医学   21篇
外科学   31358篇
综合类   23233篇
现状与发展   6篇
一般理论   7篇
预防医学   11316篇
眼科学   4912篇
药学   8799篇
  591篇
中国医学   7155篇
肿瘤学   6468篇
  2024年   541篇
  2023年   3424篇
  2022年   5106篇
  2021年   6885篇
  2020年   7833篇
  2019年   6299篇
  2018年   5595篇
  2017年   5711篇
  2016年   6238篇
  2015年   6146篇
  2014年   13186篇
  2013年   11302篇
  2012年   10635篇
  2011年   11401篇
  2010年   9592篇
  2009年   7823篇
  2008年   7062篇
  2007年   7261篇
  2006年   6250篇
  2005年   5324篇
  2004年   4214篇
  2003年   3388篇
  2002年   2501篇
  2001年   2389篇
  2000年   2019篇
  1999年   1749篇
  1998年   1384篇
  1997年   1208篇
  1996年   887篇
  1995年   719篇
  1994年   620篇
  1993年   479篇
  1992年   420篇
  1991年   376篇
  1990年   272篇
  1989年   233篇
  1988年   247篇
  1987年   226篇
  1985年   564篇
  1984年   624篇
  1983年   426篇
  1982年   467篇
  1981年   492篇
  1980年   421篇
  1979年   399篇
  1978年   354篇
  1977年   225篇
  1976年   285篇
  1975年   263篇
  1973年   219篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
Early experience with laparoscopic abdominoperineal resection   总被引:4,自引:0,他引:4  
Background: Laparoscopic abdominoperineal resection (LAPR) has not been fully evaluated as a technique in the treatment of rectal and anal cancer or inflammatory bowel disease. The purpose of our study was to evaluate the early experience with laparoscopic abdominoperineal resection at Washington University Medical Center. Methods: A prospective analysis was performed on the first 21 patients undergoing the procedure at Washington University Medical Center. Indications for surgery included rectal cancer (14 patients), anal squamous cell cancer (four patients), inflammatory bowel disease (two patients), and anal melanoma (one patient). Results: The procedure was converted to open procedure in four patients (19%). The mean (±SEM) operative time and blood loss for completed and converted LAPR were 239 ± 11 min and 424 ± 43 ml, respectively. Postoperative hematocrit dropped a mean of 8.3% ± 1.2% SEM; five patients required blood transfusion (24%). Wound complication occurred in four patients (19%; three perineal, one trocar site). Bowel function returned after a mean of 3 days, and mean postoperative hospital stay for the completed LAPR group was 5 days. Mild pain was experienced by 81% of patients (17/21) while 19% (4/21) noted moderate pain, usually of the perineal wound. The mean duration of patient-controlled analgesia use was 2 days. During the 1–44-month follow-up, six patients (29%) died from cancer (stage III or IV at operation) and only one patient developed local recurrence in the pelvis (5%). There were no trocar-site implants of cancer. Furthermore, there was no relationship between prior abdominal operations, the amount of blood loss, postoperative drop of hematocrit, or blood transfusion requirement and the length of hospitalization or complication rates. Conclusion: Laparoscopic abdominoperineal resection is a feasible alternative to the conventional open technique in both cancer and colitis patients. Received: 23 April 1996/Accepted: 8 July 1996  相似文献   
62.
Background: Increasingly larger series of laparoscopic fundoplications (LF) are being reported. A well-documented advantage of the laparoscopic approach is shortened hospital stay. Most centers report typical lengths of stay (LOS) for LF of 2–3 days. Our success with LF with a LOS of 1 day led to an attempt at performing LF on an ambulatory basis. Methods: Sixty-one consecutive patients with appropriate criteria for LF underwent surgery at our institution. Patients were counseled by the authors as to the usual postop course and progression of diet. All patients received preemptive analgesia (PEA) consisting of perioperative ketorolac and preincisional local infiltration with bupivicaine. Anesthetic management included induction with propofol, high-dose inhalational anesthetics, minimizing administration of parenteral narcotics, and avoidance of reversal of neuromuscular blockade. Immediate postop pain management included parenteral ketorolac and oral hydro- or oxycodone. All patients were given oral fluids and soft solids after transfer from the recovery room to the postoperative observation unit. Two patients were excluded from ambulatory consideration due to excessive driving distance from our hospital. Another two were hospitalized for observation after experiencing intraoperative technical problems. Results: Of 57 patients in whom same-day discharge was attempted, there were three failures requiring overnight hospitalization: All were due to pain and nausea; one patient also suffered transient urinary retention. There were no adverse outcomes related to early discharge, and there were no readmissions. One patient returned to the emergency room after delayed development of urinary retention. Median time from conclusion of operation to discharge was less than 5 h. No patients expressed dissatisfaction with early discharge on follow-up interview. Conclusions: LF can be safely performed as an ambulatory procedure. Analgesic and anesthetic management should be tailored to minimize nausea and provide adequate pain control. Received: 1 April 1996/Accepted: 29 May 1997  相似文献   
63.
64.
65.
The purpose of this paper is to detail the contraindications for surgery, with curative intent for those patients who suffer from a head and neck malignancy that invades the intracranial space. This is based on a 30-year experience of over 250 patients. The most important contraindications are anatomical. Surgery is not done if the following structures are invaded: brain stem, eloquent portions of the cerebrum, superior sagittal sinus, both internal carotid arteries, both cavernous sinuses and certain vital bridging veins. Certain tumor factors are absolute but are occasionally relative contraindications: such as distant metastatic disease especially if multiple and at multiple anatomic sites. Some tumors that behave in a particularly virulent fashion that defy complete resection but are often difficult to predict preoperatively. Lack of patient medical fitness or absence of patient commitment to the operative procedure is make-up two serious contraindications to surgery. Presented at the 77th Annual Meeting of the German Society for Oto-Rhino-Laryngology, Head and Neck Surgery, 24–28 May 2006, Mannheim, Germany.  相似文献   
66.
Intra-articular fractures of the proximal tibia present a wide spectrum of injury patterns with associated soft tissue injury. The last two decades have seen the techniques of management evolve from extensive open reduction and rigid internal fixation to arthroscopy-assisted minimal invasive surgery (MIS) and biologically benign internal fixation. The ultimate aim is to prevent the occurrence of late degenerative arthritis. This could be achieved in selected patients using minimal invasive surgery, which offers the advantages of better visualisation and management of intra-articular soft tissue injuries, confirmation of fracture reduction viewed from the joint surface, faster rehabilitation and fewer wound complications.  相似文献   
67.
The use of mechanical ventilation in the Emergency Department requires adequate resources in order to maintain patient safety and avoid potential risks. Moreover, developments in technology require increased knowledge of mechanical ventilation techniques to address the complexity of decision-making involved. Organisational issues and system factors have the potential to negatively impact on the ability of the emergency service to provide optimum care to patients receiving mechanical ventilation. These issues include staffing and skill-mix, demand on emergency services, role-delineation, scope of practice, and current mechanisms for monitoring of quality and safety. Furthermore, in response to advances in ventilator technology, current education programs for both nursing and medical staff require review to ensure that they provide comprehensive information about the types of ventilation techniques now available and the relative risks and benefits associated with their application.This article is the second in a two-part series and explores the educational and organisational factors that impact upon safety and quality of care delivered to patients receiving mechanical ventilation in the emergency department. Recommendations for future policy development, curriculum review and reporting mechanisms to support further research in the application of mechanical ventilation in the emergency department are made.  相似文献   
68.
BACKGROUND: The aim of this study was to determine the effect of laser refractive surgery on the offensive performance of professional baseball players. METHODS: Extensive search of the public media was conducted to determine which major league baseball players had undergone laser refractive surgery and when the procedure was performed. Baseball performance data were then used to determine presurgery and postsurgery baseball performance averages. A total of 17 position players were identified; however, 5 of these players were not considered in the analysis owing to insufficient playing experience either before or after the laser procedure. RESULTS: No statistically significant or practically significant difference was found between the presurgery and postsurgery means on either on-base percentage (P = 0.31), batting average (P = 0.39), slugging percentage (P = 0.66) or on-base plus slugging (OPS; P = 0.997) of major league baseball players. CONCLUSIONS: These preliminary findings suggest that professional baseball players should not expect a laser refractive surgical procedure to significantly improve their offensive baseball performance, despite the elimination of glasses or contact lens wear.  相似文献   
69.
Summary The clinical features and histological appearance of desmoplastic malignant melanoma are presented. Aggressive surgical management and close follow-up are mandatory if this highly aggressive tumor is to be controlled. Despite this, the prognosis is poor.  相似文献   
70.
Abstract: The development of a teaching package for nurse educators on drug and alcohol problems is described and the contents of its 16 modules outlined.  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