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   933265篇
  免费   65493篇
  国内免费   4841篇
耳鼻咽喉   12863篇
儿科学   29067篇
妇产科学   26494篇
基础医学   130499篇
口腔科学   25246篇
临床医学   79435篇
内科学   187951篇
皮肤病学   19335篇
神经病学   73329篇
特种医学   37687篇
外国民族医学   360篇
外科学   145216篇
综合类   25417篇
现状与发展   11篇
一般理论   247篇
预防医学   66649篇
眼科学   21182篇
药学   67220篇
  26篇
中国医学   3666篇
肿瘤学   51699篇
  2021年   7668篇
  2018年   10269篇
  2017年   8334篇
  2016年   8680篇
  2015年   10272篇
  2014年   14283篇
  2013年   20865篇
  2012年   28249篇
  2011年   29956篇
  2010年   18171篇
  2009年   17073篇
  2008年   27652篇
  2007年   29341篇
  2006年   29559篇
  2005年   29117篇
  2004年   27331篇
  2003年   26458篇
  2002年   25915篇
  2001年   42093篇
  2000年   43307篇
  1999年   37156篇
  1998年   10543篇
  1997年   9803篇
  1996年   9568篇
  1995年   8852篇
  1994年   8422篇
  1993年   7786篇
  1992年   28455篇
  1991年   27204篇
  1990年   26592篇
  1989年   25515篇
  1988年   23704篇
  1987年   23281篇
  1986年   22342篇
  1985年   21218篇
  1984年   15835篇
  1983年   13493篇
  1982年   8109篇
  1979年   14597篇
  1978年   10208篇
  1977年   8627篇
  1976年   8147篇
  1975年   8959篇
  1974年   10697篇
  1973年   10182篇
  1972年   9661篇
  1971年   8917篇
  1970年   8584篇
  1969年   8025篇
  1968年   7685篇
排序方式: 共有10000条查询结果,搜索用时 17 毫秒
991.
Sarcoglycanopathies (SGpathies) are highly frequent among severely affected limb-girdle muscular dystrophy patients. On the basis of the findings of 5 common mutations in the 4 sarcoglycan (SG) genes in the Brazilian population, we standardized a multiplex polymerase chain reaction-single-strand conformation polymorphism methodology for their concomitant analysis in DNA samples. The test was able to confirm the diagnosis in about 63% of new patients with a suspected SGpathy and was particularly important in patients in advanced stages of the disease, when obtaining a muscle biopsy for analysis may be very difficult. As common mutations have been described in several countries, this multiplex analysis could be useful for the diagnosis of SGpathies if established according to the most prevalent mutations in each population. Besides, even though the disorder studied is rare, the technique could be broadly applicable to other genes and disorders.  相似文献   
992.
Due to recent public debate and newly imposed resident work hour restrictions, we decided to investigate the relationship of resident call status to their ambulatory patients' satisfaction. Resident continuity clinic patients were asked to rate their level of satisfaction on a 10-point Likert-type scale. Using multiple regression approaches, these data were then assessed as a function of resident call status. We found that in 646 patient encounters, patient satisfaction scores were significantly less when the resident was postcall, 8.99 ± 1.8, than when not postcall, 9.31 ± 1.3. We herein discuss etiologies and implications of these findings for both patient care and medical education.  相似文献   
993.
• There are several causes for failure of appropriate position of the electrode array of the nucleus cochlear implant, e.g. incomplete insertion, extrusion, luxation, curling of the device, deviation, or false route. • If the position of the electrode array in relation to the modiolus is unsatisfactory, in order to salvage the cochlear implant one can reload the cochlear implant array with its stylet. • In order to reload the electrode array, primarily it needs to be removed from the cochlea and inserted into a small size suction tube (lubricated with just water). Then the stylet needs to be carefully straightened and inserted into the lumen of the array. • This technique is a relatively simple solution for unsatisfactory placement of the electrode array and can prevent discarding the precious cochlear implant.  相似文献   
994.
Ultrafiltration and solute transport during 60-min peritoneal dialyses of normal rabbits with intraperitoneal administration of phosphatidylcholine were compared to control values. The ultrafiltration rate of 0.27 mL/Kg/min did not increase when phosphatidylcholine was added. This agent had no effect on the ultrafiltration coefficient, sodium mass transport or solute clearances. Previously reported beneficial results with this agent could be due to repletion of a deficiency or an effect of the organic solvent. More studies of safety and efficacy of phosphatidylcholine are warranted before widespread clinical use.  相似文献   
995.
996.
997.
With the aim of defining a program of prevention for preneoplastic and neoplastic endometrial pathology which guarantees a valid, accurate and cost-contained diagnosis, 476 women considered at risk were examined. All the patients were first submitted to cytologic endocavitary withdrawal and subsequently to aspirated curettage. The cytologic and the histologic diagnoses proved concordant in 72.3% of cases of non-pathologic endometrium, in only 68.7% of preneoplastic pathology, and in 72.7% of neoplastic pathology. The non-interpretable pictures had a notable incidence (21.7%). The AA., while recognising the validity of cytology in cases of carcinoma, underline the difficulties in the diagnosis of preneoplastic lesions, and conclude that in doubtful or positive cases and subjects at risk a histologic enquiry is always necessary.  相似文献   
998.
The Istituto Rizzoli-Beretta experience with osteosarcoma of the jaw   总被引:2,自引:0,他引:2  
Twenty-eight osteosarcomas (OS) of the jaw were reported. There were 15 male and 13 female patients (age range, 9 to 68 years; mean, 36.9 years); 57.1% of the patients were older than 30 years of age. Swelling was the most frequent symptom; it was reported on an average of 6 months before diagnosis. Most of the tumors of the maxilla (eight patients) occurred in the alveolar ridge (six of eight). In the mandible (20 patients), the body was the preferred site (11 of 20). Radiographically most of the lesions were either lytic and sclerotic or only lytic. Histologically, 12 cases (42.9%) were osteoblastic osteosarcoma, ten (35.8%) were chondroblastic, four (14.3%) were fibroblastic, and two (7%) were round cell OS. Of the 28 cases, three (10.7%) were low grade, and 25 (89.3%) were high grade. Thirteen patients had intralesional surgery, and 13 had marginal surgery as their initial treatment. Recurrence was the rule in the first group, and it was 69% in the second group. Twenty patients (71%) died, and eight are alive. Of these, two are alive with disease. In the six patients who are alive and disease-free, all but one had marginal to wide surgical margins at the time of the first procedure or wide margins at the time of the recurrences along with chemotherapy or radiation therapy. In the patient in which the surgical margins were marginal, the lesion was small 2.5 X 2 cm. This patient was alive without evidence of disease after 9 years of follow-up.  相似文献   
999.
1000.
Personality of patients with pseudoseizures   总被引:7,自引:0,他引:7  
We studied personality features of 19 patients with pseudoseizures (PS) only. Scores on a personality inventory (MMPI) were compared with those of adults with generalized seizures and correlated to cognitive measures (Halstead-Reitan). Mean MMPI scores did not differ significantly, and no profile distinguished PS and epilepsy patients. MMPI abnormalities of PS patients were diverse and seldom characteristic of hysteria. Eight PS patients had cognitive impairment, two without MMPI evidence of personality disorder. These findings suggest that the etiology of pseudoseizures is multifactorial, involving different psychopathologies and sometimes cerebral dysfunction.  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