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   982篇
  免费   67篇
  国内免费   10篇
耳鼻咽喉   9篇
儿科学   18篇
妇产科学   50篇
基础医学   113篇
口腔科学   27篇
临床医学   123篇
内科学   297篇
皮肤病学   9篇
神经病学   79篇
特种医学   51篇
外科学   130篇
综合类   4篇
一般理论   1篇
预防医学   44篇
眼科学   6篇
药学   48篇
中国医学   2篇
肿瘤学   48篇
  2023年   4篇
  2022年   9篇
  2021年   25篇
  2020年   7篇
  2019年   21篇
  2018年   23篇
  2017年   20篇
  2016年   22篇
  2015年   20篇
  2014年   36篇
  2013年   51篇
  2012年   58篇
  2011年   69篇
  2010年   47篇
  2009年   51篇
  2008年   77篇
  2007年   84篇
  2006年   82篇
  2005年   93篇
  2004年   56篇
  2003年   53篇
  2002年   57篇
  2001年   14篇
  2000年   6篇
  1999年   3篇
  1998年   10篇
  1997年   5篇
  1994年   8篇
  1991年   7篇
  1990年   2篇
  1989年   5篇
  1988年   3篇
  1987年   2篇
  1983年   1篇
  1982年   2篇
  1981年   1篇
  1980年   1篇
  1979年   1篇
  1978年   1篇
  1974年   1篇
  1973年   1篇
  1970年   1篇
  1969年   1篇
  1965年   3篇
  1964年   1篇
  1963年   1篇
  1962年   3篇
  1961年   2篇
  1960年   1篇
  1959年   1篇
排序方式: 共有1059条查询结果,搜索用时 15 毫秒
31.
32.
Vassilakopoulos T  Roussos C  Zakynthinos S 《Respiratory care》2007,52(1):64-5; author reply 64-5
  相似文献   
33.
Gastrointestinal stromal tumors (GISTs) represent a rare group of neoplasms of the digestive tract deriving from the mesenchyme. Giant GISTs (over 10 cm in diameter) represent only 20 % of all cases and are associated with a high risk of malignancy. We present the case of a giant GIST of the jejunum successfully treated by surgical resection and adjuvant therapy with imatinib.  相似文献   
34.
35.
Retained surgical sponges (RSS) are an avoidable complication following surgical operations. RSS can elicit either an early exudative-type reaction or a late aseptic fibrous tissue reaction. They may remain asymptomatic for long time; when present, symptomatology varies substantially and includes septic complications (abscess formation, peritonitis) or fibrous reaction resulting in adhesion formation or fistulation into adjacent hollow organs or externally. Plain radiograph may be useful for the diagnosis; however, computed tomography is the method of choice to establish correct diagnosis preoperatively. Removal of RSS is always indicated to prevent further complications. This is usually accomplished by open surgery; rarely, endoscopic or laparoscopic removal may be successful. Prevention is of key importance to avoid not only morbidity and even mortality but also medicolegal consequences. Preventive measures include careful counting, use of sponges marked with a radiopaque marker, avoidance of use of small sponges during abdominal procedures, careful examination of the abdomen by the operating surgeon before closure, radiograph in the operating theater (either routinely or selectively), and recently, usage of barcode and radiofrequency identification technology.  相似文献   
36.
Aim: Τo determine the prevalence of impacted teeth in an adult Greek population, according to type, sex, and age. Methods: The major source of data for this study was the orthopantomographic films and the physical examinations of 425 patients (202 males and 223 females) with impacted teeth. The elements that were examined and processed were relevant to the age, sex, total number of impacted teeth, and the type and frequency of impaction of each tooth. Moreover, the associated pathology, if any, of the impacted tooth was recorded. Results: A total of 152 patients (35.8%) had one impacted tooth, 134 patients (31.5%) had two impacted teeth, and 139 patients (32.7%) had three or more impacted teeth; 777 (82.7%) impacted teeth revealed associated pathology. Conclusions: The third molars revealed the highest frequency of impaction (P < 0.001); the number of impacted teeth of the mandible was larger than that of the maxilla (P < 0.001), and the number of impacted anterior teeth in the maxilla was larger than that in the mandible (P < 0.001). Cases of impacted posterior teeth were more numerous than anterior teeth (P < 0.001). The majority of patients revealed pathological signs, which dictated the surgical removal of the impacted tooth/teeth.  相似文献   
37.
Tracheostomy is frequently required for the treatment of critically ill patients to prevent the complications with prolonged translaryngeal intubation. It may facilitate airway suctioning and improve patient comfort during the process of weaning. The purpose of the study was to introduce a new modified technique for percutaneous dilational tracheostomy (MPDT) and assess its advantages. From November 1997 through December 2000, a series of 600 patients (350 men, 250 women; mean age 44.5 years) underwent MPDT in our department. The technique we used is a combination of the Seldinger and Schachner techniques with an incision of 2 to 3 cm between the cricoid cartilage and the notch. Using a small automatic retractor, the thyroid muscles were dissected with the help of a curved mosquito clamp. This gave us the opportunity to control the isthmus and offered the possibility of ligation when the thyroid was large, providing a good operative field directly on the trachea. Hence we avoided traumatizing the isthmus, which is the main source of hemorrhage during this procedure. The mean operating time was 4.5 minutes. The morbidity rate was 0.04%. One patient developed a subcutaneous emphysema and in three cases we had to ligate the external jugular vein. The surgical incision was completely healed within 3 to 4 days after removing the tracheostoma. No tracheal stenoses were observed during the follow-up. MPDT is a safe, applicable technique that can be performed quickly even by a nonsurgeon in the intensive care unit and emergency department, with a low risk of complications because there is a direct view of the trachea and minimal trauma.  相似文献   
38.
39.
40.
Ventricular volume change in childhood   总被引:3,自引:0,他引:3  
OBJECT: The aim of this study was to construct a model of age-related changes in ventricular volume in a group of normal children ages 1 month to 15 years, which could be used for comparative studies of cerebrospinal fluid circulation disorders and cerebral atrophy developmental syndromes. METHODS: A magnetic resonance imaging-based segmentation technique was used to measure ventricular volumes in normal children; each volume was then plotted against the child's age. In addition, intracranial volumes were measured and the ratio of ventricular to intracranial volume was calculated and plotted against age. The study group included 71 normal children, 39 boys and 32 girls, whose ages ranged from 1 month to 15.3 years (mean 84.9 months, median 79 months). The mean ventricular volume was 21.3 cm3 for the whole group, 22.7 cm3 in boys and 19.6 cm3 in girls (p = 0.062, according to t-tests). The mean ventricular volume at 12 months for the whole group was 17 cm3 (20 cm3 in boys and 15 cm3 in girls), representing 65% of the volume achieved by 15 years of age (87% in boys and 53% in girls). The volume increased by a factor of 1.53, to 26 cm3 (23 cm3 in males and 28 cm3 in females, increase factors of 1.15 and 1.86, respectively) at 15 years of age. The change in ventricular volume with age is not linear, but follows a segmental pattern. These age periods were defined as: 0 to 3, 4 to 6, 7 to 10, and 11 to 16 years. A statistical difference based on sex was only demonstrated in the first 6 years of life. The mean ventricular volume for the first 6-year period was 22.4 cm3 in boys and 15.7 cm3 in girls, and the difference was significant for the two sexes (linear regression analysis for age and sex, significant according to analysis of variance regression at 0.007, p = 0.108 for age, p = 0.012 for sex). Thereafter, there was no significant difference in ventricular volume between boys and girls with further growth. The ratio of ventricular volume to intracranial volume was 0.0175 for the whole group, 0.017 in boys and 0.018 in girls (p = 0.272, according to t-tests). At 12 months of age the ratio was 0.019; it stabilized to 0.015 at 8 years of age, and increased to 0.018 at 15 years of age. No statistical difference based on sex was demonstrated with growth. CONCLUSIONS: The ventricular volume in normal children increases with age by a factor of 1.5; the increase is in a nonlinear segmental pattern. Boys have significantly higher ventricular volumes only in the first 6 years of life. The ventricular/intracranial volume ratio remains stable throughout childhood.  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