全文获取类型
收费全文 | 573篇 |
免费 | 73篇 |
国内免费 | 5篇 |
专业分类
耳鼻咽喉 | 16篇 |
儿科学 | 3篇 |
妇产科学 | 16篇 |
基础医学 | 62篇 |
口腔科学 | 4篇 |
临床医学 | 106篇 |
内科学 | 116篇 |
皮肤病学 | 10篇 |
神经病学 | 48篇 |
特种医学 | 23篇 |
外科学 | 126篇 |
综合类 | 7篇 |
预防医学 | 32篇 |
眼科学 | 4篇 |
药学 | 50篇 |
肿瘤学 | 28篇 |
出版年
2023年 | 6篇 |
2022年 | 13篇 |
2021年 | 18篇 |
2020年 | 14篇 |
2019年 | 7篇 |
2018年 | 23篇 |
2017年 | 18篇 |
2016年 | 24篇 |
2015年 | 39篇 |
2014年 | 66篇 |
2013年 | 62篇 |
2012年 | 18篇 |
2011年 | 26篇 |
2010年 | 36篇 |
2009年 | 51篇 |
2008年 | 16篇 |
2007年 | 14篇 |
2006年 | 9篇 |
2005年 | 11篇 |
2004年 | 7篇 |
2003年 | 11篇 |
2002年 | 10篇 |
2001年 | 13篇 |
2000年 | 8篇 |
1999年 | 3篇 |
1998年 | 10篇 |
1997年 | 6篇 |
1996年 | 4篇 |
1995年 | 7篇 |
1994年 | 8篇 |
1993年 | 5篇 |
1992年 | 7篇 |
1991年 | 6篇 |
1990年 | 6篇 |
1989年 | 4篇 |
1988年 | 10篇 |
1987年 | 5篇 |
1986年 | 3篇 |
1985年 | 3篇 |
1982年 | 4篇 |
1981年 | 3篇 |
1979年 | 3篇 |
1978年 | 2篇 |
1977年 | 5篇 |
1976年 | 2篇 |
1974年 | 5篇 |
1973年 | 4篇 |
1971年 | 2篇 |
1968年 | 2篇 |
1967年 | 2篇 |
排序方式: 共有651条查询结果,搜索用时 15 毫秒
81.
82.
Because reporting of complications by physicians is not reliable, monitoring of the hospital course of surgical patients by nurses can improve effectiveness of identifying complications. Monitoring the course of only those patients who remain in the hospital more than four postoperative days will disclose 90 per cent of complications expected in all patients undergoing operation. Twenty hours per week of a nurse's time is sufficient to monitor 1,300 such patients annually. Identification of patients with large hospital bills will include most patients with complicated hospital courses but does not discriminate them from the large number of uncomplicated courses which also generate large hospital charges. 相似文献
83.
George J. Taylor IV Willard S. Harris Morton D. Bogdonoff 《The Journal of clinical investigation》1971,50(7):1546-1550
After inhaling fluoroalkane gases, which are used as aerosol propellants, some people have died suddently and unexpectedly. Seeking an explanation, we had 14 monkeys inhale these gases. All developed ventricular premature beats, bigeminy, or tachycardia, which began at an average of 39 (SE +/-4.2) sec. Fluoroalkanes were present in blood, but arterial hypoxemia or hypercapnia was absent, and arterial pressure was reduced only slightly. In contrast, without fluoroalkanes, 3 min of asphyxia or anoxia caused arrhythmias in only one monkey whose arterial oxygen tension had fallen to 16 mm Hg. The ventricular arrhythmias caused in well oxygenated monkeys by fluoroalkane gases may either be mediated through beta adrenergic receptors, since propranolol abolished these arrhythmias, or result from a nonadrenergic, direct, toxic effect of these gases on the heart. These results suggest that some deaths after propellant inhalation may be caused by ventricular tachycardia or fibrillation. 相似文献
84.
M.S.Alice T. Gasch Ph.D.O.E. Michaelis IV Ph.D.Larry W. Douglass Ph.D.Phylis B. Moser 《Nutrition Research》1984,4(6):967-976
Twelve carbohydrate-sensitive and 12 non-carbohydrate sensitive (normal) men were studied. Carbohydrate sensitivity was identified by hyperinsulinemic and normoglycemic responses to a sucrose load. In a blocked split-plot design, fasted subjects were given 2 g/kg body weight of sucrose or invert sugar, and responses of plasma zinc, copper, insulin, and glucose were determined. Erythrocyte zinc and copper also were measured. Blood samples were taken 0, 0.5, 1, 2, and 3 hours after the sugar loads were given. Plasma zinc, copper, insulin, and glucose did not differ significantly between the two sugar loads. Neither did erythrocyte zinc and copper differ significantly between the two load doses. Also, plasma zinc, copper, and glucose, as well as erythrocyte zinc and copper, did not differ significantly between the carbohydrate-sensitive and normal men. Plasma insulin was significantly higher in the carbohydrate-sensitive than the normal men. Plasma zinc did not change significantly between sampling times. Plasma copper declined progressively over the testing period. The greater the elevation of plasma glucose above the fasting level, the greater the plasma copper was depressed. Copper appears to be withdrawn from plasma after sugar loading to facilitate glucose uptake and metabolism. 相似文献
85.
A case of congenital orbital teratoma is presented with illustrations and discussion of typical radiographic features which may facilitate preoperative diagnosis and treatment. 相似文献
86.
87.
88.
T. D. East IV N. L. Pace D. R. Westenskow K. Lund 《Acta anaesthesiologica Scandinavica》1983,27(5):356-360
Differential lung ventilation with positive end expiratory pressure (PEEP) improves pulmonary gas exchange when used in the supportive care of patients with severe unilateral or asymmetrical lung disease. Once the provision of selective PEEP to the two lungs is accomplished, the best method of partitioning the tidal volume between the two lungs is unknown. Twelve mongrel dogs were given a unilateral hydrochloric acid (HCl) aspiration injury. A computer controlled differential lung ventilation system was used to ventilate four dogs with equal volumes to each lung, four dogs with equal driving pressure (end inspiratory pressure-PEEP) to each lung, and four dogs with equal end-tidal CO2 fraction from each lung. The respiratory rate was feedback controlled to maintain Paco2 at 4.67 kPa. The dogs were kept supine and ventilated with 30% O2 . Following injury, the PEEP was set at 0 kPa for 1 h. The dogs were then given 1.36 kPa and 2.72 kPa PEEP to the injured lung for 2 h in a cross-over fashion. The assignment of the tidal volume controller, the side of injury, and the PEEP sequence was random. Oxygen tension fell and pulmonary venous admixture increased after giving the HCl injury. In all three groups considered simultaneously, unilateral PEEP improved Pao2 and venous admixture. The equal tidal volume distribution was the only group to show a significant improvement in Pao2 at both PEEP increments (0 to 1.36 kPa and 2.72 kPa). There was a significant difference in tidal volume allocation between the three groups with the equal end-tidal and equal pause pressure groups only minimally ventilating the injured lung. With differential lung ventilation and unilateral PEEP, equal partitioning of tidal volume provides the highest Pao2 , compared to the other two methods of partitioning tidal volume. 相似文献
89.
High glucose-induced endothelial cell dysfunction is considered to be the main cause of the development of vascular diabetes complications. Cultured endothelial cells exposed to high glucose in vitro demonstrate a variety of alterations, including extracellular matrix (ECM) deposition, growth inhibition, and changes in cell motility. Some of these effects were shown to be mediated by the up-regulation of endothelial transforming growth factor-beta1 (TGFbeta1) secretion and activation. We investigated the influence of high glucose on human immortalized endothelial cell line ECV304. According to our data, confluent cells exposed to 30 mM glucose for 48 h secrete the increased amount of total and active TGFbeta1 ( approximately 1.4-fold), and accumulate more chondroitin sulphate (CS) in their conditioned medium, pericellular matrix, and cell layer ( approximately 1.6- to 2.0-fold). By blocking the coupling of CS chains to the core protein with p-nitrophenyl-beta-D-xyloside and by chondroitinase ABC treatment, we demonstrated that the increased accumulation of pericellular CS is accompanied by increased cell attachment to immobilized hyaluronic acid (HA), while the expression of cell surface CD44 remains unaltered. Since the exogenous TGFbeta1 affects ECV304 cells in a similar manner, and anti-TGFbeta1-neutralizing antibody cancels the effect of high glucose, we suggest the involvement of TGFbeta1 in the development of endothelial cell response to high glucose in terms of CS accumulation and cell binding to HA. 相似文献