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Radiology conferences enable participants the opportunity to ask experts questions through question and answer (Q and A) sessions or individually. Given the time limitations and intimidating circumstances, we incorporated conference text messaging (confexting) as a method of increasing interactivity between the audience and speakers. During a 5-day radiology conference, text messaging was utilized for anonymous interactivity between the audience and speakers during Q and A sessions. There were 324 text messages; 76 of these were either follow-up statements or questions related to earlier text messages. Forty-two questions were submitted via paper notes. There was a general trend of an increasing number of text messages and a decreasing number of paper notes. The anonymous text messaging system was found to be an effective method for interactivity between the audience and the speakers. The questions and answers could be presented in a PowerPoint format at the formal Q and A sessions. Questions texted to the authors during their talks could be immediately answered or addressed in subsequent talks. Although difficult for some individuals to embrace technology, confexting allows for interactivity and prompts discussion. Confexting is an effective method for interactivity between the audience and speakers not previously utilized in a conference setting. The anonymity and asynchronous communication enable conference participants to submit more questions than in the traditional setting. The speakers may be able to explain more thoroughly difficult concepts more thoroughly with additional slides at Q and A sessions or may immediately answer texted questions during their talks.  相似文献   
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AIM: To examine blood flow in renal and intrarenal arteries and its changes in the acute pharmacological test with captopril in patients with chronic glomerulonephritis (CGN). MATERIAL AND METHODS: Renal circulation was studied in 50 patients with CGN using ultrasound dopplerography (USDG) of renal vessels on the unit GE Logiq 400 CL PRO Series. The velocity and indices of peripheral blood resistance in the major renal artery (RA) and in intrarenal arteries were estimated. In 26 patients the blood flow was studied again after intake of 50 mg captopril. RESULTS: Poor renal blood flow was registered in cortical parenchyma in 36% CGN patients (with chronic renal failure in 75%). Multifactorial regression analysis has demonstrated that only blood creatinine was independently related with slowing down of the blood flow at the level of RA and intrarenal arteries. Morphological index of activity correlated with resistance indices while a high sclerosis index correlated with blood flow slowing. Older patients had higher resistance indices. Captopril significantly accelerated blood flow and insignificantly changed indices of peripheral resistance including those in CRF patients. CONCLUSION: Poor blood flow in the cortical layer of renal parenchyma in CGN, according to USDG, occurs rather frequently and was associated with CRF and older age of the patients. Blocking of renin-angiotensin system at the level of angiotensin II formation improves renal blood flow in most of the patients.  相似文献   
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Phospholipase A2 levels in acute chest syndrome of sickle cell disease   总被引:4,自引:2,他引:4  
Acute chest syndrome (ACS) is associated with significant morbidity and is the leading cause of death in patients with sickle cell disease (SCD). Recent reports suggest that bone marrow fat embolism can be detected in many cases of severe ACS. Secretory phospholipase A2 (sPLA2) is an important inflammatory mediator and liberates free fatty acids, which are felt to be responsible for the acute lung injury of the fat embolism syndrome. We measured SPLA2 levels in 35 SCD patients during 20 admissions for ACS, 10 admissions for vaso-occlusive crisis, and during 12 clinic visits when patients were at the steady state. Eleven non-SCD patients with pneumonia were also evaluated. To determine if there was a relationship between sPLA2 and the severity of ACS we correlated SPLA2 levels with the clinical course of the patient. In comparison with normal controls (mean = 3.1 +/- 1.1 ng/mL), the non- SCD patients with pneumonia (mean = 68.6 +/- 82.9 ng/mL) and all three SCD patient groups had an elevation of SPLA2 (steady state mean = 10.0 +/- 8.4 ng/mL; vaso-occlusive crisis mean = 23.7 +/- 40.5 ng/mL; ACS mean = 336 +/- 209 ng/mL). In patients with ACS sPLA2 levels were 100- fold greater than normal control values, 35 times greater than values in SCD patients at baseline, and five times greater than non-SCD patients with pneumonia. The degree of SPLA2 elevation in ACS correlated with three different measures of clinical severity and, in patients followed sequentially, the rise in SPLA2 coincided with the onset of ACS. The dramatic elevation of SPLA2 in patients with ACS but not in patients with vaso-occlusive crisis or non-SCD patients with pneumonia and the correlation between levels of SPLA2 and clinical severity suggest a role for SPLA2 in the diagnosis and, perhaps, in the pathophysiology of patients with ACS.  相似文献   
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Cerebral malaria is thought to involve specific attachment of Plasmodium falciparum-infected knobby red cells to venular endothelium. The nature of surface ligands on host endothelial cells that may mediate cytoadherence is poorly understood. We have investigated the effects of soluble thrombospondin, rabbit antiserum raised against thrombospondin, and human immune serum on cytoadherence of parasitized erythrocytes in ex vivo mesocecum vasculature. Preincubation of infected red cells with soluble thrombospondin or human immune serum inhibits binding of infected red cells to rat venular endothelium. Infusion of the microcirculatory preparation with rabbit antithrombospondin antibodies before perfusion of parasitized erythrocytes also resulted in decreased cytoadherence. In addition, incubation of infected cells with human immune sera obtained from malaria patients significantly inhibited the observed cytoadherence. Our results indicate that thrombospondin mediates binding of infected red cells to venular endothelium and may thus be involved in the pathogenesis of cerebral malaria.  相似文献   
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A survey was undertaken to examine the impact of Medicare's Prospective Payment System (PPS) and other recent changes in the health care environment on providers' decisions regarding acquisition of high-cost technologic equipment. The survey group included 199 hospitals and freestanding imaging centers known to have acquired magnetic resonance (MR) imaging units, as well as a random sample of 400 hospitals whose acquisition decisions were unknown to the authors. Fifty-eight percent of the known adopters and 61% of the randomly selected hospitals responded to the survey. Nonadopters' decisions were dominated by economic considerations, including the high cost of MR imagers and concerns about Medicare's reimbursement policies. Competition and a desire to provide the highest quality of care are counterbalancing the retardant effects of PPS, however, and are stimulating widespread diffusion of MR imagers.  相似文献   
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Three-component (cyclosporin A, corticosteroids and azathioprine) immunosuppression has been widely introduced in the treatment of recipients of renal transplants because it allows a significant reduction of the components' doses in greater effectiveness. The analysis of the results of 83 puncture biopsies obtained in the immediate postoperative period after kidney transplantation has shown that administration of an imidazole derivative allows raising therapeutic concentration of cyclosporin up to 200-300 ng/ml, thus preventing rejection crises. However, increased blood concentration of cyclosporin does not increase its toxicity as a result of a significant fall in the overall level of the metabolites.  相似文献   
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The Brazilian Diabetes Society is starting an innovative project of quantitative assessment of medical arguments of and implementing a new way of elaborating SBD Position Statements. The final aim of this particular project is to propose a new Brazilian algorithm for the treatment of type 2 diabetes, based on the opinions of endocrinologists surveyed from a poll conducted on the Brazilian Diabetes Society website regarding the latest algorithm proposed by American Diabetes Association /European Association for the Study of Diabetes, published in January 2009.An additional source used, as a basis for the new algorithm, was to assess the acceptability of controversial arguments published in international literature, through a panel of renowned Brazilian specialists. Thirty controversial arguments in diabetes have been selected with their respective references, where each argument was assessed and scored according to its acceptability level and personal conviction of each member of the evaluation panel.This methodology was adapted using a similar approach to the one adopted in the recent position statement by the American College of Cardiology on coronary revascularization, of which not only cardiologists took part, but also specialists of other related areas.  相似文献   
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