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   16826篇
  免费   767篇
  国内免费   137篇
耳鼻咽喉   169篇
儿科学   360篇
妇产科学   123篇
基础医学   2139篇
口腔科学   303篇
临床医学   1072篇
内科学   4486篇
皮肤病学   445篇
神经病学   1399篇
特种医学   535篇
外科学   2690篇
综合类   46篇
一般理论   4篇
预防医学   361篇
眼科学   618篇
药学   1120篇
中国医学   28篇
肿瘤学   1832篇
  2023年   94篇
  2022年   175篇
  2021年   444篇
  2020年   215篇
  2019年   274篇
  2018年   346篇
  2017年   274篇
  2016年   368篇
  2015年   412篇
  2014年   500篇
  2013年   610篇
  2012年   1088篇
  2011年   1149篇
  2010年   683篇
  2009年   575篇
  2008年   1001篇
  2007年   1143篇
  2006年   1068篇
  2005年   1217篇
  2004年   1196篇
  2003年   1058篇
  2002年   1099篇
  2001年   189篇
  2000年   137篇
  1999年   222篇
  1998年   286篇
  1997年   209篇
  1996年   215篇
  1995年   187篇
  1994年   160篇
  1993年   171篇
  1992年   101篇
  1991年   88篇
  1990年   92篇
  1989年   82篇
  1988年   58篇
  1987年   42篇
  1986年   43篇
  1985年   41篇
  1984年   44篇
  1983年   36篇
  1982年   42篇
  1981年   40篇
  1980年   32篇
  1979年   31篇
  1978年   36篇
  1977年   26篇
  1976年   13篇
  1975年   11篇
  1974年   13篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
A 54-year-old male who experienced a syncopal episode underwent aortic valve replacement for aortic stenosis and regurgitation. The aortic valve was incompetent as a result of thickening of the left coronary cusp and noncoronary cusp. In addition a saccular aneurysm was indicated on the left coronary cusp. A shelf of tissue protruding at right angles from the ventricular septum was particularly prominent below the right coronary cusp, resulting in subvalvular stenosis. The cause of the saccular aneurysm was most likely caused by the long-term effects of the jet stream instigated by discrete subaortic stenosis.  相似文献   
992.
This study aims to estimate the tolerable lactose intake which can be utilized in the digestion by lactase and in the fermentation by intestinal microbes in Japanese female adults. The first, the maximum permissive dosage of lactose not to induce transitory diarrhea was estimated based on the oral ingestion of lactose at several dose levels in all the subjects, and compared with that of lactitol which is not hydrolyzed by digestive enzymes. A second lactose tolerance test involving 10 g and 30 g of lactose was carried out in 10 subjects showing resistance to diarrhea, and serum glucose and insulin levels and the amount of hydrogen excreted in the breath were measured for comparison with those of glucose and lactitol. Subjects were 43 Japanese female adults (average: age 20.5+/-2.1 y, weight 51.3+/-5.1 kg) who had not been diagnosed as having either hypolactasia or being lactose intolerant. Serum glucose and insulin levels were scarcely elevated following the ingestion of both 10 g and 30 g of lactose, while the amount of hydrogen excreted in the breath was greatly increased following the ingestion of 30 g of lactose, but these levels were less following the ingestion of 10 g of lactose. In contrast, the ingestion of 15 g of glucose significantly increased blood glucose and insulin levels, while no hydrogen was detected in the breath. The maximum permissive dosage of lactose not to induce transitory diarrhea was 0.72 g/kg of body weight and that of lactitol was 0.36 g/kg of body weight in Japanese adults. The digestive capacity of lactase is less than 10 g of lactose by single ingestion, while intestinal microflora are able to ferment approximately 20-30 g of lactose. In addition, the ingestion of more than 10 g of lactose might be contributed as prebiotics.  相似文献   
993.
It has been reported that ingested magnets can cause intestinal fistula formation or perforation, leading to intestinal obstruction. However, there are no previous case reports that magnet ingestion additionally caused an intestinal volvulus. We report herein the case of a 1-year-old boy in whom the ingested magnets caused a volvulus of part of the small intestine leading to the resection of the necrotic portion. We think that if more than one magnet is found as a foreign body in the intestine, they should be removed immediately by laparotomy. Clinicians who care for children should be aware of this unexpected risk.  相似文献   
994.
995.
The treatment of massive osteolysis with lymphangioma and/or hemangioma (Gorham-Stout syndrome) has been controversial. The authors report on a patient with multiple massive osteolyses and extensive lymph-hemangiomatosis whose lesions were reduced by interferon alfa therapy.A 2-year-old girl had complained of left chylothorax. Thoracoscopy showed an increase in small lymphatic vessels in the chest wall. The chylothorax was improved by coagulation of the lymphatic vessels. Later, multiple massive osteolyses appeared in the left 11th and 12th ribs, the TH10-L3 vertebrae, and the right femur. There were also hemangiomas in the liver and spleen, a tumor lesion in the left lower chest wall, and hemangiomatous change on the skin surface of the left back. The left lung had only a minimal air content. After OK-432 was injected into the femur and chest wall lesions, the femur lesion disappeared. Then, as right chylothorax appeared, OK-432 was injected into the right pulmonary cavity. The chylothorax disappeared, but pericardial effusion appeared. After steroid pulse therapy, pericardial effusion disappeared. During these treatments, the 7th to 10th ribs disappeared from the x-ray and scoliosis developed. One month later, a cloudy fluid collection in the right lung was found on computed tomography. Interferon alfa and steroid pulse therapy were started. Interferon alfa (1,500,000 units) was subcutaneously administered daily for 2 months and was gradually reduced and maintained at 1,500,000 unit/wk. Steroids were also reduced and maintained at 5 mg/d of predonine. Later, the progress of osteolysis and the extension of lymph-hemangiomatosis stopped. Ten months later, hemangioma in the back disappeared, and the 7th to 10th ribs, which had disappeared, reappeared. The interferon alfa therapy was stopped 14 months after it was administered. The patient's condition has been stable for 10 months since then. At this time, computed tomography shows regression of the hemangiomatous lesion in the back.The authors clinically diagnosed the patient as having Gorham-Stout syndrome with extension of lymph-hemangiomatosis. Interferon alfa with or without steroid therapy should be a choice for patients with extension lesions.  相似文献   
996.
997.
998.
999.
Treatment of congenital pseudarthrosis of the tibia (CPT) remains a challenge. To clarify the current situation in treatment, a multicenter study was carried out to obtain information on the results of CPT treatment. The objective of this study was to propose appropriate treatment guidelines for CPT. Records of 73 patients with CPT who underwent surgical treatment were collected from 32 hospitals. The modality of the treatment was 26 with Ilizarov technique, 25 with free vascularized fibular graft, 7 with a combination of the two techniques, 6 with intramedullary nailing with free bone grafting, 5 plating with free bone grafting, and 4 with other treatments. Fifty-four procedures resulted in union, 7 resulted in delayed union, 7 were left un-united, 1 underwent amputation, and the results were unknown in 4. According to the results of this study, the most acceptable methods of treatment of CPT are the Ilizarov method and the vascularized fibular graft.  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