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11.
D K Carson J R Council J E Gravley 《Journal of developmental and behavioral pediatrics : JDBP》1991,12(3):141-147
Findings from a study of 47 children 4 to 12 years old who received tonsillectomies at a children's hospital indicated that adjustment before hospitalization was the strongest predictor of postsurgical adjustment. However, certain temperamental and mother-child relationship factors also were strongly related to and predictive of posthospitalization outcomes. Children who displayed the most positive reactions were temperamentally more rhythmical (i.e., had regular, predictable behavior), more approaching to new experiences and people, more adaptable to change and positive in mood, and more responsive. Although family adaptability and cohesion were not significantly associated with children's reactions to hospitalization, maternal trait anxiety and maternal overprotection, rejection, and overindulgence of the child were correlated with poorer adjustment. The findings have practical implications to helping children adjust more effectively to surgery and hospitalization, and they contribute to our understanding of resiliency and vulnerability in children. 相似文献
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Henryk J Salacinski Nigel R Tai Robert J Carson Alan Edwards George Hamilton Alexander M Seifalian 《Journal of biomedical materials research》2002,59(2):207-218
Poly(ester)urethane and poly(ether)urethane vascular grafts fail in vivo because of hydrolytic and oxidative degradative mechanisms. Studies have shown that poly(carbonate)urethanes have enhanced resistance. There is still a need for a viable, nonrigid, small-diameter, synthetic vascular graft. In this study, we sought to confirm this by exposing a novel formulation of compliant poly(carbonate-urea)urethane (CPU) manufactured by an innovative process, resulting in a stress-free. Small-diameter prosthesis, and a conventional poly(ether)urethane Pulse-Tec graft known to readily undergo oxidation in a variety of degradative solutions, and we assessed them for the development of oxidative and hydrolytic degradation, changes in elastic properties, and chemical stability. To simulate the in vivo environment, we used buffered solutions of phospholipase A(2) and cholesterol esterase; solutions of H(2)O(2)/CoCl(2), t-butyl peroxide/CoCl(2) (t-but/CoCl(2)), and glutathione/t-butyl peroxide/CoCl(2) (Glut/t-but/CoCl(2)); and plasma fractions I-IV, which were derived from fresh human plasma centrifuged in poly(ethylene glycol). To act as a negative control, both graft types were incubated in distilled water. Samples of both graft types (100 mm with a 5.0-mm inner diameter) were incubated in these solutions at 37 degrees C for 70 days before environmental scanning electron microscopy, radial tensile strength and quality control, gel permeation chromatography, and in vitro compliance assessments were performed. Oxidative degradation was ascertained from significant changes in molecular weight with respect to a control on all Pulse-Tec grafts treated with t-but/CoCl(2), Glut/t-but/CoCl(2), and plasma fractions I-III. Pulse-Tec grafts exposed to the H(2)O(2)/CoCl(2) mixture had significantly greater compliance than controls incubated in distilled water (p < 0.001 at 50 mmHg). No changes in molecular weight with respect to the control were observed for the CPU samples; only those immersed in t-but/CoCl(2) and Glut/t-but/CoCl(2) showed an 11% increase in molecular weight to 108,000. Only CPU grafts treated with the Glut/t-but/CoCl(2) mixture exhibited significantly greater compliance (p < 0.05 at 50 mmHg). Overall, results from this study indicate that CPU presents a far greater chemical stability than poly(ether)-urethane grafts do. 相似文献
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D J Doudet C A McLellan R Carson H R Adams H Miyake T G Aigner R T Finn R M Cohen 《Journal of cerebral blood flow and metabolism》1991,11(5):726-734
Most attempts to model accurately [18F]-DOPA imaging of the dopamine system are based on the assumptions that its main peripheral metabolite, 3-O-methyl-6-[18F]fluoro-L-DOPA ([18F]3-OM-DOPA), crosses the blood-brain barrier but is present as a homogenous distribution throughout the brain, in part because it is not converted into [18F]DOPA in significant quantities. These assumptions were based mainly on data in rodents. Little information is available in the primate. To verify the accuracy of the above assumptions, we administered 18F-labeled 3-OM-DOPA to normal rhesus monkeys and animals with lesions of the DA nigrostriatal system. No selective 18F regional accumulation in brain was apparent in normal or lesioned animals. The plasma metabolite analysis revealed that only the negatively charged metabolites (e.g., sulfated conjugates) that do not cross the blood-brain barrier were found in significant quantities in the plasma. A one-compartment, three-parameter model was adequate to describe the kinetics of [18F]3-OM-DOPA. In conclusion, assumptions concerning [18F]3-OM-DOPA's behavior in brain appear acceptable for [18F]DOPA modeling purposes. 相似文献
16.
J. Keith Smith M.D. Ph.D. Gordon C. Carson III M.D. Jay D. Johnson B.S. John H. Harris Jr. M.D. D.Sc. F.A.C.R. 《Emergency radiology》1994,1(2):78-80
Purpose: To describe an educational computer aided instruction program dealing with diagnosis and classification of facial
fractures.
Methods: A program was created for use on Macintosh computers using a graphic presentation package. This program allows for
the display of high resolution digitized radiographic images and illustrations, along with integrated voice and text information.
Users can interact with the program to review complex concepts or study additional cases. Case material was obtained from
selected high quality plain radiographs and computed tomography (CT) scans obtained in the trauma center of one institution,
and was scanned on a high resolution digital scanner with image parameters optimized for viewing on the Macintosh high resolution
color monitor.
Results: The program has been installed in the computer aided instructional laboratories or trauma centers at The University
of Texas Health Science Center, Houston; The University of Alabama, Birmingham; Emory University School of Medicine, Atlanta,
Georgia; and The University of North Carolina, Chapel Hill. The program is available to radiology residents and medical students
rotating on the trauma radiology services at these institutions. Completion of the program requires 30–45 minutes.
Conclusion: Based on our initial experience, the program has been used by residents in the training programs of all institutions
with favorable results. 相似文献
17.
H Yamanaka E H Willis C A Penning C L Peebles E M Tan D A Carson 《The Journal of clinical investigation》1987,80(3):900-904
The chromatin-bound enzyme poly(ADP-ribose) polymerase (ADPRP) is strongly stimulated by DNA with single- or double-stranded breaks, and transfers the ADP-ribose moiety of NAD to nuclear proteins. The activation of ADPRP is important for DNA repair and replication, and also has been postulated to play a role in the pathogenesis of lymphocyte dysfunction associated with chronic inflammatory diseases, and inborn errors of nucleoside metabolism. We have detected high titers of IgG autoantibodies to the ADPRP protein in six patients with rheumatic complaints. No other autoantibodies were detected in any of the six sera. The specificity of the anti-enzyme antibodies was established by (a) immunoprecipitation of ADPRP activity, (b) immunoprecipitation and immunoblotting of both the native 116-kD enzyme and its proteolytic digestion products. ADPRP was purified from human thymus and calf thymus. The autoantibodies reacted equivalently with both enzymes. The anti-ADPRP antibodies had a distinctive immunofluorescent pattern with HEp-2 cells, reacting intensely with nucleoli and metaphase chromosomes, and diffusely with the nucleus. Autoantibodies to ADPRP have not been described previously. The presence of a specific immune response against an enzyme that has been associated with various immunodeficiency syndromes raises intriguing possibilities concerning the relationship between DNA damage, immunodeficiency, and autoimmunity. 相似文献
18.
Pernes JM; Vitoux JF; Brenoit P; Raynaud A; Parola JL; Roth JP; Angel CY; Fiessinger JN; Roncato M; Gaux JC 《Radiology》1986,158(2):481-485
Thirty-five patients hospitalized for recent angiographically documented arterial occlusion in the legs (27 femoropopliteal arteries and eight grafts) benefited from local fibrinolytic therapy delivered at the site of the occlusion with a 4- or 5-F catheter. This therapy combined a continuous urokinase (UK) infusion of 1,000 U/kg/hour and a lysyl plasminogen (LYS-PLG) infusion of 15 microkatals every 30 minutes. Angiographically confirmed lysis was obtained in 85% of the cases. Only 3% of the patients had major and 6% had minor groin hematomas. Only two patients had concentrations of fibrinogen as low as 100 mg/dl. Intravascular infusion of UK-LYS-PLG is as effective as streptokinase. Its excellent tolerance makes it a good alternative in the treatment of acute ischemia in the lower limbs. 相似文献
19.
20.
Short-Ti inversion-recovery pulse sequence: analysis and initial experience in cancer imaging 总被引:2,自引:0,他引:2
Inversion recovery (IR), commonly considered a pulse sequence capable of producing T1-weighted images with excellent display of normal anatomy, is versatile: The null point and peak time provide a useful, succinct summary of the properties of IR and its capacity for producing both T1- and T2-weighted images. Shortening of the inversion time (TI) and creation of a short-TI inversion-recovery (STIR) pulse sequence increases sensitivity to malignancy and other abnormalities by making the effects of prolonged T1 and T2 on signal intensity additive and by nulling the signal from fat. The authors examined over 300 patients with various malignancies and compared STIR images with T1- and T2-weighted images obtained at 0.5 T. In 43 cases, signal-difference-to-noise ratios (SD/Ns) were calculated between tumor, fat, and muscle. In general, STIR images demonstrated tumor as a conspicuously high-intensity area in a background of muted, discernible anatomic detail. The good contrast achieved with STIR sequences between tumor and fat (SD/N = 18.1) and tumor and muscle (SD/N = 12.9) consolidated into a single image the information contained separately on T1- and T2-weighted images, which facilitates efficient detection and localization of malignancy. 相似文献