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   24784篇
  免费   1271篇
  国内免费   78篇
耳鼻咽喉   334篇
儿科学   1383篇
妇产科学   609篇
基础医学   2763篇
口腔科学   563篇
临床医学   1414篇
内科学   5239篇
皮肤病学   781篇
神经病学   1521篇
特种医学   774篇
外科学   3197篇
综合类   761篇
一般理论   15篇
预防医学   1240篇
眼科学   1384篇
药学   2257篇
中国医学   181篇
肿瘤学   1717篇
  2023年   153篇
  2022年   342篇
  2021年   894篇
  2020年   436篇
  2019年   563篇
  2018年   721篇
  2017年   494篇
  2016年   617篇
  2015年   580篇
  2014年   922篇
  2013年   1126篇
  2012年   1589篇
  2011年   1728篇
  2010年   926篇
  2009年   769篇
  2008年   1190篇
  2007年   1241篇
  2006年   1234篇
  2005年   1056篇
  2004年   972篇
  2003年   826篇
  2002年   755篇
  2001年   700篇
  2000年   704篇
  1999年   558篇
  1998年   227篇
  1997年   164篇
  1996年   144篇
  1995年   150篇
  1994年   114篇
  1993年   99篇
  1992年   367篇
  1991年   370篇
  1990年   338篇
  1989年   328篇
  1988年   284篇
  1987年   251篇
  1986年   234篇
  1985年   232篇
  1984年   171篇
  1983年   135篇
  1981年   91篇
  1979年   157篇
  1978年   97篇
  1977年   81篇
  1975年   83篇
  1974年   100篇
  1973年   92篇
  1972年   118篇
  1970年   78篇
排序方式: 共有10000条查询结果,搜索用时 859 毫秒
41.
Summary We have completed a phase I and pharmacology study of liposomally-encapsulated daunorubicin (DaunoXome). Of 32 patients entered, 30 were evaluable. No toxicity was encountered at the initial doseescalation steps from 10 to 60 mg/m2. At 80 mg/m2, two patients manifested grade 2 neutropenia. At least grade 3 neutropenia occurred in all patients receiving 120 mg/m2. Alopecia and subjective intolerance were mild. Cardiotoxicity was not observed except for an episode of arrhythmia in a patient with lung cancer and prior radiation. Only one minor objective response was observed in this population of refractory solid tumors. Pharmacokinetics differed from those of the free drug with no detection of daunorubicinol. We recommend future phase II studies with a dose of 100 mg/m2 in previously treated and 120 mg/m2 of DaunoXome in previously untreated patients with solid tumors.EDW is supported in part by ACS award 92-14-1  相似文献   
42.
Paediatric dacryocystorhinostomy   总被引:1,自引:0,他引:1  
Of 258 cases of dacryocystorhinostomy performed on children in the period September 1981 to September 1991, 130 were for simple, unresolved congenital nasolacrimal duct obstruction. Other indications for surgery included punctal agenesis, lacrimal fistula, post-traumatic and post-inflammatory canalicular obstruction. Of 177 children without canalicular pathology, 171 (96%) were relieved of symptoms with one operation, without canalicular intubation. Of 81 cases with canalicular disease, 55 of 70 (79%) who underwent DCR plus canalicular intubation, and 10 of 11 who underwent DCR plus Lester-Jones tube, were substantially improved with one operation. No child required peroperative or postoperative blood transfusion. Dacryocystorhinostomy in childhood, in experienced surgical hands, is a safe procedure, achieving relief of symptoms in most cases, particularly in the absence of canalicular disease.  相似文献   
43.
Between November 1988 and February 1992, 416 patients required coronary endarterectomy for diffuse coronary artery disease. This constitutes 16.19 per cent of all patients who underwent coronary artery bypass grafting during the same period. A total of 528 endarterectomies were performed. Four-hundred and twenty-two endarterectomies were performed on right coronary system and 106 endarterectomies were performed on left coronary system. One-hundred and twelve (26.92%) patients required more than one endarterectomies. The hospital mortality was 2.16 percent. 3.37 per cent of patients had perioperative infarction. Intraaortic balloon pump was required in 1.92 per cent of patients. 5.77 per cent of the patients had significant arrhythmias. The patients have been followed up for a mean period of 27 months. One-hundred and forty patients were evaluated by exercise multigated radionuclide angiogram. One-hundred and thirty-four (95.71%) patients showed increase in ejection fraction as compared to preoperative value. Six (4.29%) patients did not show any significant change while eight (5.71%) patients had fall in ejection fraction. Postoperative coronary angiogram was done in 44 patients at a mean of 10 months. 89.59 per cent of grafts to the endarterectomised vessels and 91.67% of grafts to nonendarterectomised vessel were patent. The difference between the two groups was not statistically significant.  相似文献   
44.
Several neurons from different nuclei give rise to descending spinal tracts and project to various levels in the spinal cord of goldfish, Carassius auratus. These were visualized by retrograde transport of horseradish peroxidase (HRP) administered to the bilaterally transected spinal cord at 6 levels, corresponding to 1st, 5th, 10th, 15th, 20th and 25gh segments of the vertebral column. As many as 16 brain nuclei or neuronal aggregations and the Mauthner cells project posteriorly up to the 20th spinal segment. Restricted neurons of the dorsolateral area in the nucleus preopticus magnocellularis and those of the ventromedial nucleus of the thalamus projected up to the 20th and 25th segments respectively. In the mesencephalon, the nucleus ruber and the nucleus of the medial longitudinal fasciculus revealed retrogradely labeled somata; the former extended up to the 20th segment, while the latter projected up to the 25th segment. The remaining descending projected neurons of the brain belonged to the rhombencephalon. The nucleus of the lateral lemniscus; anterior, magnocellular, descending and posterior divisions of the octaval nucleus: raphe nucleus; Mauthner cell and the neurons located adjacent to the trigeminal tract and those in the vicinity of the secondary gustatory tract sent their processes up to 20th segmental level. However, somata of the superior, medial and inferior divisions of the reticular nucleus and restricted neurons of the facial lobe extended up to 25th segmental level. The pattern of neuronal projections into the spinal cord suggests a topographic organization.  相似文献   
45.
The intestinal uptake of [14C]oxalate, [14C]glyoxylate, and [14C]glycolate are studied in brush border membrane vesicles (BBMV) isolated from vitamin A-deficient and pair-fed control rats. The data obtained indicate that oxalate and its precursors are transported across the BBMV by passive diffusion. The intestinal uptake of glyoxylate and glycolate remains unaltered in vitamin A deficiency, while uptake rate of oxalate was significantly increased (p less than 0.01) in vitamin A-deficient rats as compared to pair-fed controls. In conclusion, the results indicate that vitamin A deficiency leads to hyperabsorption of oxalate through the gut.  相似文献   
46.
47.
48.
Spontaneous gall bladder perforation in infants is rare. We report a 3-month-old male infant who presented with progressive abdominal distension, low-grade fever, bilateral hydrocele and acholic stools. Ultrasonography showed free fluid in the peritoneal cavity, which was bile-stained on paracentesis. Surgical exploration revealed sterile biliary peritonitis and a gangrenous gall bladder. Partial cholecystectomy with external biliary drainage resulted in satisfactory recovery.  相似文献   
49.
Gall bladder perforation is a potentially life-threatening condition. Spontaneous perforation is infrequent and rarely seen in the absence of gallstones but gall bladder perforation is an occasional complication of typhoid fever. If such perforations are not treated in time, mortality rates are very high. We report a case of gall bladder perforation complicating typhoid fever following enteric perforation of the ileum necessitating sequential laparotomies during the same admission.  相似文献   
50.
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