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   900620篇
  免费   62502篇
  国内免费   2341篇
耳鼻咽喉   12495篇
儿科学   28714篇
妇产科学   26254篇
基础医学   126712篇
口腔科学   24737篇
临床医学   74842篇
内科学   183339篇
皮肤病学   19008篇
神经病学   71466篇
特种医学   36459篇
外国民族医学   336篇
外科学   142207篇
综合类   19040篇
一般理论   247篇
预防医学   64640篇
眼科学   20131篇
药学   63857篇
中国医学   1798篇
肿瘤学   49181篇
  2018年   9113篇
  2017年   7199篇
  2016年   7707篇
  2015年   8760篇
  2014年   12397篇
  2013年   19284篇
  2012年   25737篇
  2011年   27323篇
  2010年   16632篇
  2009年   15819篇
  2008年   26192篇
  2007年   27795篇
  2006年   27976篇
  2005年   27482篇
  2004年   26325篇
  2003年   25489篇
  2002年   25079篇
  2001年   41363篇
  2000年   42562篇
  1999年   36272篇
  1998年   9973篇
  1997年   9152篇
  1996年   9085篇
  1995年   8447篇
  1994年   8084篇
  1993年   7586篇
  1992年   28202篇
  1991年   26982篇
  1990年   26415篇
  1989年   25348篇
  1988年   23554篇
  1987年   23172篇
  1986年   22251篇
  1985年   21152篇
  1984年   15806篇
  1983年   13479篇
  1982年   8088篇
  1979年   14592篇
  1978年   10208篇
  1977年   8628篇
  1976年   8147篇
  1975年   8960篇
  1974年   10699篇
  1973年   10183篇
  1972年   9661篇
  1971年   8918篇
  1970年   8584篇
  1969年   8026篇
  1968年   7684篇
  1967年   7086篇
排序方式: 共有10000条查询结果,搜索用时 8 毫秒
961.
Type IIIC tibial fractures are complex injuries involving extensive bone and soft-tissue devascularization that result in a high percentage of complications and ultimate amputation. An emergency free flap transfer not only may salvage the limb but also may improve the aesthetic and functional results of reconstruction by placing the injured structures in a well-vascularized bed. Two cases of type IIIC tibial fracture were treated in this manner, and we present our experience with a 30-month follow-up of one patient and a 6-month follow-up of another patient.  相似文献   
962.
In the experiment on dogs and in patients with duodenal ulcer disease, it was established that the regulation of acid production besides the vagal nerves was mediated by the intragastric gastrin transport with the blood flow. A method of preoperative diagnosis of the intensity of intragastric blood flow permitting to define more accurately the indications for the choice of a method for surgical treatment has been developed. Supplementation of the selective proximal vagotomy with circular mucosectomy at the boundary between the antrum and body of a stomach enhances the effectiveness of operation due to reduction of the antral gastrin influence on the acid-producing zones of the stomach.  相似文献   
963.
Reports of a dramatic decrease in tumor recurrence and regression of muscle invasive disease with oral bacillus Calmette-Guerin prompted us to conduct a randomized prospective comparison of oral bacillus Calmette-Guerin with the standard intravesical plus percutaneous therapy. Oral therapy consisted of 200 mg. Tice bacillus Calmette-Guerin 3 times each week. Intravesical and percutaneous Tice bacillus Calmette-Guerin at a dose of 50 mg. was given weekly for 6 weeks, at 8, 10 and 12 weeks, then at 6 months and every 6 months thereafter. Minimal side effects confirmed the safety of oral bacillus Calmette-Guerin. Tumor recurrence was documented in 21 of 33 oral bacillus Calmette-Guerin patients (64%) and 18 of 55 (33%) who received intravesical plus percutaneous therapy (p less than 0.002, chi-square test). We were unable to demonstrate any antitumor activity of oral bacillus Calmette-Guerin in this study.  相似文献   
964.
M A Levison  D D Thomas  R G Wiencek  R F Wilson 《The Journal of trauma》1990,30(3):247-51; discussion 251-3
The records of 239 patients surviving more than 24 hours with full-thickness intraperitoneal colonic injuries over a 7-year period were reviewed. During the first 3 years, 29% (31/106) of the patients were managed by primary repair without colostomy. In the next 4 years, almost twice as many patients, 56% (75/133), with similar colonic trauma were treated without fecal diversion (p less than 0.05). Although there was no difference in the mean Trauma Score in the patients with primary repair in the two time periods, the Injury Severity Score (mean +/- sd) in the patients without colostomy in the later periods was significantly higher (17.8 +/- 2.1 vs. 20.2 +/- 5.1) (p less than 0.001). No patient suffered because of the increased incidence of primary repairs. These patients had five abdominal abscesses and only one leak, whereas the patients with colostomy had 15 intraperitoneal abscesses. Because of the safety when primary repair is performed, more liberal use of primary colonic repair following penetrating trauma is warranted.  相似文献   
965.
966.
Patients with morbid obesity present a series of functional and morphologic alterations and require a careful planning for anesthetic management. We report a case of a woman weighing 260 kg who was operated on twice for the treatment of her base condition. In the first operation, general anesthesia was carried out and in the second one, epidural anesthesia was conducted. Main complications included hypoxemia and hypercapnia which persisted during the first week after operation carried out under general anesthesia.  相似文献   
967.
Total parenteral nutrition is now a broadly used method whose efficacy is confirmed, even if it is still not free from risk of complications. The Authors report their own clinical experience on 130 cases in the period 1981-1988. Complications were registered in 4.6% of the observed cases. They underline the problems relating to this subject.  相似文献   
968.
969.
A method of graphic representation of time factors in cancer mortality is presented, based on different tonalities of grey applied to the surface of the matrix defined by various age-specific rates. It is illustrated using mortality data from cancers of the mouth or pharynx, oesophagus, larynx and lung in Italian and Swiss males. Progressively more complex regression surface equations are defined, on the basis of two independent variables (age and cohort) and a dependent one (each age-specific rate). General patterns of trends were thus identified, showing important similarities in cohort and period effects, but also noticeable differences in time-related factors in mortality from various neoplasms of the upper digestive and respiratory tract. For instance, there were declines in mortality from cancers of the mouth or pharynx in the oldest age groups, whereas rates were appreciably upwards at younger and middle age, particularly in Italy. Likewise, cancers of the oesophagus and, chiefly, of the larynx were substantially increasing, on a cohort basis, in oldest Italian males. Temporal pattern for laryngeal cancer in Italy was similar to that of lung cancer, thus suggesting that (cigarette) smoking has a greater impact on this cancer site as compared with alcohol. However, it is difficult to explain, on this basis alone, the totally diverging pattern for cancer of the larynx (downwards) and of the lung (upwards) observed among older Swiss males. These examples indicate that trend surface models are a useful summary guide to illustrate and understand the general patterns of age, period and cohort effects in cancer mortality.  相似文献   
970.
Alternative techniques were introduced in the last 20 years for the treatment of gallstones. Among these the extracorporeal shock wave lithotripsy followed by a systemic litholytic therapy represents undoubtedly the most attractive one. A group of two surgeons and two gastroenterologists has started to evaluate this treatment in April 1988, using a piezoceramic lithotryptic system (Piezolith 2300). From April 1988 to May 1989 we have treated 32 patients who fulfilled the selection criteria-symptomatic gallstone disease, 1-3 radiolucent concrements of less than 30 mm of diameter, functioning gallbladder. We noted only one pancreatitis as a complication of this treatment. The overall stonefree rate is 16% after two months, 32% after four months and 56% after six months, depending on the size and number of stones. A definitive evaluation and final conclusion will only be possible when the rate of late recurrences after this treatment will be known.  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