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   278篇
  免费   16篇
  国内免费   1篇
儿科学   4篇
妇产科学   4篇
基础医学   58篇
口腔科学   8篇
临床医学   32篇
内科学   63篇
皮肤病学   7篇
神经病学   9篇
特种医学   13篇
外国民族医学   1篇
外科学   21篇
综合类   5篇
预防医学   8篇
眼科学   6篇
药学   37篇
肿瘤学   19篇
  2023年   7篇
  2022年   9篇
  2021年   11篇
  2020年   7篇
  2019年   9篇
  2018年   11篇
  2017年   3篇
  2016年   3篇
  2015年   7篇
  2014年   6篇
  2013年   13篇
  2012年   8篇
  2011年   15篇
  2010年   13篇
  2009年   4篇
  2008年   16篇
  2007年   14篇
  2006年   12篇
  2005年   11篇
  2004年   17篇
  2003年   8篇
  2002年   16篇
  2001年   11篇
  2000年   9篇
  1999年   7篇
  1998年   3篇
  1996年   1篇
  1995年   1篇
  1994年   1篇
  1993年   1篇
  1992年   3篇
  1991年   4篇
  1990年   9篇
  1989年   2篇
  1988年   6篇
  1987年   2篇
  1986年   1篇
  1985年   1篇
  1984年   1篇
  1982年   2篇
  1979年   1篇
  1977年   1篇
  1975年   3篇
  1971年   1篇
  1970年   3篇
  1968年   1篇
排序方式: 共有295条查询结果,搜索用时 15 毫秒
41.
OBJECTIVE: Weaning predictors are often incorporated in protocols to predict weaning outcome for patients on mechanical ventilation. The predictors are used as a decision point in protocols to determine whether a patient may advance to a spontaneous breathing trial. The impact of including predictors in a weaning protocol has not been previously studied. We designed a study to determine the effect of including a weaning predictor (frequency-tidal volume ratio, or f/Vt) in a weaning protocol. DESIGN: Randomized, blinded controlled trial. SETTING: Academic teaching hospitals. PATIENTS: Three hundred and four patients admitted to intensive care units at three academic teaching hospitals. INTERVENTIONS: Patients were screened daily for measures of oxygenation, cough and secretions, adequate mental status, and hemodynamic stability. Patients were randomized to two groups; in one group the f/Vt was measured but not used in the decision to wean (n = 151), but in the other group, f/Vt was measured and used, using a threshold of 105 breaths/min/L (n = 153). Patients passing the screen received a 2-hr spontaneous breathing trial. Patients passing the spontaneous breathing trial were eligible for an extubation attempt. MEASUREMENTS AND MAIN RESULTS: Groups were similar with regard to gender, age, and Acute Physiology and Chronic Health Evaluation II score. The median duration for weaning time was significantly shorter in the group where the weaning predictor was not used (2.0 vs. 3.0 days, p = .04). There was no difference with regard to the extubation failure, in-hospital mortality rate, tracheostomy, or unplanned extubation. CONCLUSIONS: Including a weaning predictor (f/Vt) in a protocol prolonged weaning time. In addition, the predictor did not confer survival benefit or reduce the incidence of extubation failure or tracheostomy. The results of this study indicate that f/Vt should not be used routinely in weaning decision making.  相似文献   
42.
43.
44.
45.
BackgroundImmunizations have led to a decrease in the incidence of invasive meningococcal disease (IMD) in Canada, but this infection still leads to significant morbidity and mortality.ObjectivesThe purpose of this study was to determine the burden of illness and management of IMD in paediatric hospitals.MethodsData were collected on all cases of IMD in eight paediatric hospitals from 2013 to 2017.ResultsThere were 17 cases of IMD. Three of eight hospitals had no cases. Just over half of the cases were serogroup B (n=9); a quarter (n=4) were serogroup W; less than a quarter (n=3) were serogroup Y; and one was unknown. Two infected children were not started on antibiotics until day one and day five after the initial blood culture was collected, but had uneventful recoveries. Six cases required admission to intensive care units; two died. Six cases had probable or proven meningitis. Thrombocytopenia was documented in seven cases. All cases had elevated C-reactive protein levels. Seven children received more than seven days of antibiotics; of these seven, only two had complications that justified prolonged therapy (subdural empyema and septic knee). Six cases had a central line placed.ConclusionIMD is now rare in Canadian children, but about one-third of the cases in our study required treatment in the intensive care unit and two died. Clinicians appear to not always be aware that a five to seven-day course is adequate for uncomplicated cases of bacteremia or meningitis.  相似文献   
46.
A 5-year-old-boy presented with a right pleural effusion and fever. A tumorous mass was located between the right lung and the liver. The boy underwent a right thoracotomy with excision of the tumor and the adherent parts of the right hemidiaphragm. Histology and immunohistochemistry showed an inflammatory pseudotumor of the diaphragm. This is the first reported case of an inflammatory pseudotumor in this location. A brief review of the heterogeneous theories about the pathogenesis and the different therapeutic regimens for this rare neoplastic entity are discussed. Accepted: 17 June 1998  相似文献   
47.
48.
We report the control of drug release rate from Mg(2)Al-layered double hydroxides (Mg(2)Al-LDHs) intercalated with ibuprofen as a model drug. Different aggregation states in the dry powders of ibuprofen intercalated Mg(2)Al-LDHs can be obtained due to different particle interactions by changing the materials synthesis parameters including the solvent system and aging conditions. Compared with the samples prepared in water alone or aged at atmospheric conditions (70 degrees C, 3 days), the sample synthesized in the mixture of ethylene glycol and water (volume ratio of 1:1) and aged hydrothermally (150 degrees C, 18 h) exhibits a more stable suspension of regularly shaped and larger LDH platelets (ca. 450 nm). Upon drying, it forms relatively oriented dense powder through preferential face-to-face and edge-to-edge aggregation. The release rate of ibuprofen from such dense powder is considerably lower compared with those from the loose powders. This can be attributed to a less breakdown of aggregates, a longer diffusion path length and a higher diffusion resistance in the oriented solid matrix.  相似文献   
49.
Elevated levels of IL-17 in systemic lupus erythematosus (SLE) patients have been reported to be correlated to renal disorders, but the involvement of the G-197A gene polymorphism of IL 17 in lupus nephritis (LN) and the degree of renal abnormality have not been reported. Therefore, the aim of this study was to investigate these associations. This study involved 30 LN patients and 20 healthy control. Levels of uIL-17 were measured by ELISA, while the G-197A gene polymorphisms of IL-17A were examined using polymerase chain reaction (PCR) and sequence analysis. Changes in the protein structure due to G-197A gene polymorphism of IL-17A were analyzed by in silico investigation. In addition, renal biopsies were performed to determine the degree of renal abnormality (classes I–VI). A significant difference was found between LN patients and the control group in term of uIL-17 levels (p?=?0.004). However, the G-197A gene polymorphism of IL-17A between LN patients and the control group were not significantly different (p?=?0.154). There were no difference in the levels of uIL-17 between patients and control group on G-197A gene polymorphism of IL-17A (p?=?0.682). Also, there were no significant differences in G-197A gene polymorphism of IL-17A toward the degree of nephritis (p?=?0.300). In silico investigation showed that G197A gene polymorphism of IL-17A resulted in changes of the pattern of IRF-4 binding to the promoter, thereby affecting its activity. In conclusion, the levels of uIL-17 in LN patients were significantly higher than those in the control group, but G-197A gene polymorphism of IL-17A did not cause varying levels of IL-17 and did not influence the degree of renal abnormalities in LN.  相似文献   
50.
The evaluation of Safe Motherhood programmes has been hampered by difficulties in measuring the preferred outcomes of maternal mortality and morbidity. The need for adequate indicators has led researchers and programme managers alike to resort to indicators of utilization and quality of health services. In this study we assess the magnitude of four indicators of use of essential obstetric care (EOC) and one indicator of quality of care in health facilities in three districts in South Kalimantan, Indonesia. The general picture which emerges for South Kalimantan is that the use of obstetric services is low. Even in the more urban district of Banjar where facility-based coverage is highest, fewer than 14% of all deliveries take place in an EOC facility, 2% of expected births are admitted to such a facility with a major obstetric intervention (MOI), and 1% of expected births have an MOI for an absolute maternal indication. The use of facility-based EOC is consistently lower in Barito Kuala compared to the other districts, and the differences persist regardless of the indicators used. In this setting with low utilization rates, general rates of utilization of EOC facilities seem to be as satisfactory an indicator of relative access to EOC as more elaborate indicators specifying the reasons for admission. The inequalities in access to care revealed by the various indicators of use of EOC services may prove to be a more powerful stimulus for change than the widely reported and highly inaccurate accounts of the high levels of maternal mortality.  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