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941.
Although teleradiology systems are available commercially, they are expensive ($30,000), and different makes are incompatible with each other, making them unusable for interhospital image transfers. Standard components were added to a personal computer (PC) to build a functional teleradiology unit capable of interhospital image transmission at a low cost ($600 upgrade). This PC teleradiology system was studied to assess its accuracy in the interpretation of soft-tissue lateral neck x-rays with epiglottitis or retropharyngeal abscesses and elbow x-rays with joint effusions, fractures, or both. A radiologist and a pediatric emergency physician were asked to read the PC teleradiology images. Both physicians read 13 of 13 soft-tissue lateral neck x-rays and 15 of 15 elbow x-rays correctly. This study supports the premise that PC teleradiology can be used to facilitate telephone consultation and patient transfers between tertiary pediatric emergency centers by transmitting pertinent radiographic information over a phone line. Although verbal communication can often suffice in a telephone consultation or transfer, there are many instances when visualizing a radiographic image such as an x-ray or computed tomography scan can provide important information that cannot be optimally described verbally. Rural hospitals can form interhospital image transmission links with tertiary center resources. Tertiary centers may elect to organize interhospital image transmission and referral networks with their rural hospital sources. 相似文献
942.
Sdo C Jorge DD Kormann P Medeiros JC Mateos MM Zamorano LM Silva MN Zambonini AS Arnoni JE Assef HM Magalh?es 《Canadian Metallurgical Quarterly》1994,62(4):243-246
Five patients who had permanent pacemaker and infective endocarditis were analyzed. Diagnose was confirmed by a positive blood cultures in all patients and 2 of them had identifiable vegetation in the echocardiogram too. The etiologic agent was Staphylococcus aureus in 3, Staphylococcus epidermidis in 1 and Staphylococcus viridans in 1. Three patients were treated with antibiotics alone: one had no clinical conditions to be operated, one died before surgery and one had good response to antimicrobial therapy alone. Two patients were submitted to antibiotic therapy and surgical removal of the pacemaker system, without complications. It was concluded that the surgical removal of the pacemaker system, as soon as possible, is the choice's therapy. 相似文献
943.
YC Patel AS Galanopoulou SN Rabbani JL Liu M Ravazzola M Amherdt 《Canadian Metallurgical Quarterly》1997,131(2):183-194
Seven neutralizing monoclonal antibodies (nMAbs) produced against serotype Asia-1 foot-and-mouth disease virus (FMDV) were used to select neutralization-resistant variants. Seven single and six multiple antibody-resistant variants were selected to identify neutralization antigenic sites on FMDV Asia-1. The variants no longer reacted with nMAbs which were used to select them when tested by microneutralization test (MNT), radioimmunoassay (RIA) and agar gel immunodiffusion (AGID) assay. Based on the binding and neutralization patterns of the variants, the nMAbs could be divided into discrete groups indicating the presence of three independent antigenic sites with evidence for occurrence of possibly a fourth site on the virus surface. Site 1 was present on 140S, 12Sps and VP1 and thus was conformation-independent. Sites 2 and 3 were restricted to the intact virion (140S) and thus were more conformation-dependent. Site 4 present on 140S virions and 12S protein subunits was less conformation-dependent. The site 3 nMAbs neutralized the infectivity of all the ten different Asia-1 virus isolates tested indicating that this site is conserved in Asia-1 virus serotype. Both cross-neutralization of different Asia-1 viruses with the nMAbs and cross-inhibition assays between MAbs demonstrated that the nMAbs recognized at least six different epitopes on Asia-1 virus. 相似文献
944.
945.
Peptides containing proline residues, except at the N-terminus, exist in cis and trans forms due to the rigidity of the peptidyl-proline bond. Computer-simulated and experimental electropherograms have been used to study the interplay of the electrophoretic migration and the kinetics of the cis-trans interconversion. The measure of the interference by the reaction is the dimensionless Damk?hler number (Da) which is the ratio of the migrant's residence time to the characteristic time of reaction in the capillary. The fraction of the trans conformer that is not separable with 90% purity is employed to quantify the extent of overlap between the concentration profiles of the two interconverting migrants and the effect of the various operational variables was examined by simulation. The deterioration of separation, as measured by the degree of overlap, is a quasi sigmoidal function of Da with the selectivity and the intrinsic efficiency of the system as the parameters. At sufficiently low temperatures the interference by reaction kinetics may vanish and the two conformers are separated. At high enough temperatures, when the rate of interconversion is very fast, the two conformers are not separated at all. A simple and rapid method is proposed for estimation of kinetic parameters for the cis-trans isomerization on the basis of data obtained with phenylalanyl-proline dipeptide. The procedure involves determination of the equilibrium constant by measuring equilibrium concentrations of the two conformers using nuclear magnetic resonance (NMR) or capillary zone electrophoresis (CZE) at very low temperature, correlation of the peak shapes in the electropherograms with the Da, and finally, evaluation of the forward rate constants from the assigned Da values in the domain: 0.01 < Da < 0.5. Separations using CZE were performed in the temperature range of 1-40 degrees C by using the Beckman P/ACE unit equipped with an auxiliary cooling system. The kinetic data thus obtained showed good agreement (average error less than 5%) with those measured by NMR. 相似文献
946.
947.
FO Fran?a LA Benvenuti HW Fan DR Dos Santos SH Hain FR Picchi-Martins JL Cardoso AS Kamiguti RD Theakston DA Warrell 《Canadian Metallurgical Quarterly》1994,87(5):269-282
In S?o Paulo State, Brazil, five males, aged between 8 and 64 years, were attacked by 'Africanized' honey bees (Apis mellifera scutellata). The estimated number of stings received by each patient ranged from > 200 to > 1000. All five were transferred to intensive care units in S?o Paulo City. Clinical features included intravascular haemolysis, respiratory distress with ARDS, hepatic dysfunction, rhabdomyolysis (with myoglobinaemia and myoglobinuria), hypertension and myocardial damage (perhaps explained by release of endogenous catecholamines by venom phospholipase A2 and mellitin), shock, coma, acute renal failure and bleeding. Laboratory findings included gross neutrophil leucocytosis, elevated serum enzymes [AST, ALT, LDH, CPK (predominantly CPK-MM)] and creatinine. Clotting times were slightly prolonged. Despite treatment with antihistamines, corticosteroids, bronchodilators, vasodilators, bicarbonate, mannitol and mechanical ventilation, three of the patients died between 22 and 71 h after the attacks, with histopathological features of ARDS, hepatocellular necrosis, acute tubular necrosis, focal subendocardial necrosis and disseminated intravascular coagulation. Whole bee venom and phospholipase A2 (PLA2) antigen concentrations were measured in serum and urine for the first time, using enzyme immunoassay. High venom and PLA2 concentrations were detected in serum and urine for more than 50 h after the stings in two fatal cases, in one of which the total circulating unbound whole venom was estimated at 27 mg, one hour after the attack. An antivenom should be developed to treat the increasing numbers of victims of mass attacks by Africanized 'killer' bees in USA, Middle and South America. 相似文献
948.
949.
Fluorescence quenching of perylene by Co2+ and Ni2+ ions has been investigated both below and above the phase transition temperature in small unilamellar DPPC vesicles. Classic F?rster type energy transfer was observed for perylene quenched by Co2+ ions below the phase transition when the effects of donor-donor energy transfer are taken into account. In the liquid crystalline phase a simple diffusion theory incorporating energy transfer was found to model the system well. For quenching by Ni2+ ions both above and below the phase transition temperature in lipid bilayers and in glycerol the data did not follow classic F?rster type energy transfer but indicated that an additional quenching mechanism was present. A mechanism other than F?rster behaviour was also observed for the quenching by Cr3+ ions in glycerol. 相似文献
950.
U Atabek L Barot M Matthews AS Brown RK Spence L Mossberg RC Camishion 《Canadian Metallurgical Quarterly》1993,90(5):379-382
The author developed a new original method of exploration and treatment of salivary glands: ultrafine fibroscopy. After having briefly described the material, as well as the method and indications, he shows how lithiases can now be extracted through natural pathways thanks to the manufacture of a miniaturized basket probe, avoiding major surgery. 相似文献