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   1976篇
  免费   114篇
  国内免费   9篇
耳鼻咽喉   26篇
儿科学   15篇
妇产科学   16篇
基础医学   231篇
口腔科学   80篇
临床医学   126篇
内科学   605篇
皮肤病学   13篇
神经病学   138篇
特种医学   31篇
外科学   460篇
综合类   8篇
预防医学   70篇
眼科学   47篇
药学   95篇
中国医学   1篇
肿瘤学   137篇
  2022年   12篇
  2021年   19篇
  2020年   13篇
  2019年   21篇
  2018年   31篇
  2017年   15篇
  2016年   26篇
  2015年   24篇
  2014年   28篇
  2013年   32篇
  2012年   65篇
  2011年   59篇
  2010年   35篇
  2009年   34篇
  2008年   56篇
  2007年   60篇
  2006年   69篇
  2005年   78篇
  2004年   82篇
  2003年   76篇
  2002年   101篇
  2001年   77篇
  2000年   96篇
  1999年   83篇
  1998年   40篇
  1997年   29篇
  1996年   23篇
  1995年   13篇
  1994年   10篇
  1993年   18篇
  1992年   83篇
  1991年   67篇
  1990年   68篇
  1989年   50篇
  1988年   56篇
  1987年   46篇
  1986年   52篇
  1985年   53篇
  1984年   41篇
  1983年   32篇
  1982年   16篇
  1981年   29篇
  1979年   35篇
  1977年   11篇
  1974年   13篇
  1972年   11篇
  1971年   12篇
  1969年   10篇
  1968年   14篇
  1966年   10篇
排序方式: 共有2099条查询结果,搜索用时 0 毫秒
991.
A diabetic patient was admitted to our hospital for infective endocarditis with acute purulent pericarditis and diabetic ketoacidosis. Echocardiography revealed attachment of vegetation to the chordae tendineae in the left ventricle and pericaridial effusion. The vegetation was enlarged and pendulated for a few days despite maximal antimicrobial therapy. Surgical resection was desirable to decrease the risk of embolic complications and cardiovascular collapse. We could not open the heart because of accumulation of purulent pericardial fluid, and right renal infarction was complicated. We believe that the immunocompromised and hypercoagulable state due to diabetes caused these conditions.  相似文献   
992.
Abstract: An oral adsorbent (AST‐120) that removes uremic toxin has attenuated the progression of renal dysfunction. Although there were decreased serum creatinine (Scr) levels observed during administration, it is expected that the action of an oral adsorbent is different according to the patient. In the present study, the difference in the background was clarified. Methods: A total of 842 patients whose Scr had increased from 3.8 to 4.8 mg/dL during the prior 5.2 months were investigated. Antihypertensive medications and dietary protein intake were unmodified during 6 months administration. The patients were divided into three efficacy groups based on the changes in Scr level; those who had a decrease in Scr were grouped as Group A (N = 290), while those with a <1.5‐fold increase were defined as Group B (N = 428) and those with a ≥1.5‐fold increase were defined as Group C (N = 124). Results: Before administration, these three groups were indistinguishable by the Scr level. No Group A patient went onto dialysis, whereas 12% and 40% of Group B and C patients, respectively, required dialysis. In Group A, the slopes of 1/Scr over time, serum urea nitrogen, uric acid, phosphate, total protein, and diastolic blood pressure were all improved. Group B improved moderately and Group C showed less improvement. Conclusions: In this study, a fairly large number of patients (29% of the population) were believed to be the first case to report the reversibility of severe chronic renal failure. Except in patients with hypoproteinemia, hypercholesterolemia, anemia or hypertension, AST‐120 either attenuates or arrests the progression in patients with severe chronic glomerulonephritis.  相似文献   
993.
Summary Experimental hyperthyroidism induced in rats by daily injections of 3,3,5,5-tetraiode-l-thyroxine (0.5 mg/kg i.p.) for 14 days resulted in a significant increase in heart weight and heart weight/body weight ratio. Hemodynamic and morphological studies were performed in one group. Thyroxine-treated rats showed a characteristic cardiovascular hyperdynamic state, such as tachycardia and augmented rate of contraction, but no evidence of heart failure such as elevated end-diastolic pressures. The cardiac cells in hyperthyroid rats had a significantly larger diameter and more mitochondria than did those of the control rats. In another group the activities of cardiac enzymes involved in energy utilization and liberation were measured biochemically and compared with those of normal controls. Hyperthyroidism resulted in increased specific activity of cytochrome C oxidase and actomyosin ATPase in the myocardium. The specific activity of long-chain acyl-CoA synthetase, carnitine palmityltransferase, carnitine acetyltransferase, malate dehydrogenase and citrate synthase showed a moderate to marked increment, whereas the specific activity of lactate dehydrogenase and pyruvate kinase remained at the control values. These results suggest that in hyperthyroid rat hearts the functions of both energy liberation and utilization systems are enhanced to meet the added workload. Moreover, the increased activity of the enzymes participating in fatty acid metabolism suggest that in thyroxine-induced hypertrophic and hyperdynamic rat hearts, fatty acids contribute more to the energy supply than do carbohydrates.This study was supported in part by a grant-in-aid for scientific research from the Ministry of Education, Science and Culture of the Japanese Government.  相似文献   
994.
A 50-year-old man was admitted to hospital for dysphagia. The upper gastrointestinal series revealed esophageal stricture, pyloric stenosis, and hypomotile small intestine. He was diagnosed with systemic sclerosis sine scleroderma with gastrointestinal involvement. After subtotal gastrectomy with Billroth 2 anastomosis, he had recurrent intestinal pseudo-obstruction and perforation of the afferent loop. Our experience indicates that surgical procedures in bowel scleroderma, in which an afferent loop is reconstructed, could easily cause perforation of the afferent loop.  相似文献   
995.
Paraduodenal hernia is a rare condition in which the small bowel loops are herniated into an unusual fossa in the periduodenal area. We treated a patient with paraduodenal hernia diagnosed pre-operatively. A 28-year-old woman was admitted to our hospital because of intermittent abdominal pain. Abdominal ultrasonography revealed a large tumor adjacent to the pancreas. Provisional diagnosis made according to computed tomography (CT) findings was tumor of the pancreas tail. However, on a CT scan performed after the administration of diatrizoate meglumine/diatrizoate sodium (Gastrografin, Schering, Berlin, Germany) the mass was shown as a jejunum loop located between the stomach and the pancreas body. Subsequent laparotomy revealed that the jejunum loop was herniated into an unusually large mesocolic fossa and that the hernial orifice was covered by the adhesion between the transverse and descending colons. It seemed that the small intestine within the mesocolic fossa was strangulated by this adhesion. The patient's abdominal pain resolved postoperatively. These observations suggest that paraduodenal hernia should be suspected in patients with chronic, atypical abdominal pain, regardless of the findings for small bowel obstruction. (Received Oct. 6, 1997; accepted Jan. 23, 1998)  相似文献   
996.
Minimally invasive transanal surgery for localized rectal carcinoid tumors   总被引:2,自引:0,他引:2  
Local excision is often fully justified for rectal carcinoid tumors. However insufficient surgical field and difficult access to proximal tumors have been drawbacks in performing pre-existing local excision procedures. A novel local excisional technique called minimally invasive transanal surgery (MITAS) has been experimented for local removal of carcinoid tumors in the rectum. A specially designed anal retractor connected to the Octopus retractor holder was used and an ENDO-stapler allowed the simultaneous excision and anastomosis to be performed. Eight patients with carcinoid tumors in the rectum (4 tumors in the upper rectum) underwent MITAS. Median distance from anal verge to proximal tumor was 6.5 cm (range, 5–12 cm). The median diameter of the tumor was 9 mm. Median operative time was 18.5 minutes and blood loss was minimal. No analgesics were needed postoperatively, and there was no morbidity or mortality. Full-thickness excision of the rectum was accomplished and the tumors confined in the submucosa were demonstrated histologically to be with free surgical margins. No recurrences have been observed with a median follow-up period of 39 months. The technique facilitates total excisional biopsy for rectal carcinoid tumors and reduces operative time, blood loss and complications. Received: 10 January 2002 / Accepted in revised form: 28 January 2002  相似文献   
997.
998.
999.
Cavernous hemangioma of the liver with cyst formation is a very rare condition. A case of cavernous hemangioma of the liver with unilocular giant cyst formation undergoing surgical removal is reported. Notably, the patient also had Budd-Chiari syndrome with an obstructing lesion in the inferior vena cava. The cystic degeneration of the hemangioma implied a relationship with apoptosis. This is the first reported case of Budd-Chiari syndrome caused by advanced cystic degeneration of hepatic cavernous hemangioma.  相似文献   
1000.
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