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11.
J. Randolph Swartz Ira M. Lesser Kyle B. Boone Bruce L. Miller Ismael Mena 《International journal of geriatric psychiatry》1995,10(6):437-446
Global and regional cerebral blood flow (CBF) were evaluated with single photon emission computerized tomography (SPECT) utilizing both 133Xenon (133Xe) (47 subjects, 47–82 years old) and 99Tc-hexamethylpropyleneamine oxime (99Tc-HMPAO) (27 subjects, 47–80 years old). The 133Xe results showed: among total subjects, no age-related decline in global CBF, but a significant regional decline in the occipital lobe (p < 0.05); among men, significant age-related declines in global, frontal, temporal, occipital and right hemisphere CBF (all p < 0.05); among women, no age-related decline in global or regional CBF. The 99Tc-HMPAO results showed no age-related decline in either global or regional perfusion among total subjects, men or women. These results suggest that age-related global and regional (including frontal lobe) CBF declines do not occur in healthy control subjects after the age of 45 years. However, gender differences in age-related CBF changes warrant further study. 相似文献
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J. M. Greally L. Y. Boone S. G. Lenkey S. L. Wenger M. W. Steele 《American journal of medical genetics. Part A》1992,44(3):334-339
A child with manifestations of acrogeria and metageria, two “premature aging” syndromes, is presented. Because of his indistinct phenotype and because the question has been previously raised as to whether these conditions are separate, we propose the designation of acrometageria to describe this phenotypic continuum. As there is much in common clinically between acrometageria and the syndrome of type III procollagen deficiency (Ehlers-Danlos type IV), it might be presumed that a similar pathogenesis for acrometageria exists. This possibility has been tested previously, without demonstrating specific quantitative or qualitative deficits, but with some indirect evidence that collagen metabolism is deranged in these patients. One such crude indicator is the elevation of urinary hyaluronic acid levels, demonstrated in our patient and also observed in the phenotypically distinct Werner and Hutchinson-Gilford premature aging syndromes. On one hand, it could be argued that this supports the concept that premature aging syndromes exist as a biological continuum. On the other hand, it is equally valid to argue that syndromes of premature aging are so described merely because they include recognizable changes of normal aging and that the demonstration of an underlying mutation in a collagen gene, for example, invalidates their study as models of accelerated normal aging. © Wiley-Liss, Inc. 相似文献
14.
Radiation levels near an imaging chain commonly used in angiography were measured with both a 100- and a 200-mm-thick scatter phantom. The scatter was measured in lines parallel in space to the central ray of the x-ray beam, at lateral distances of 300, 500, and 800 mm. The effects of fluoroscopic kilovoltage and image intensifier magnification mode were also measured. The results indicate that the highest scattered radiation levels occur near the surface of the patient where the x-ray beam enters. Exposure rates were measured in both anteroposterior (AP) and posteroanterior (PA) geometries on a U-arm system. In PA geometry, the highest radiation levels occur below the angiographer's waist, an area well protected by the lead apron. The AP geometry increases the exposure rate to the neck, head, and upper extremities, areas where apron shielding is less effective. 相似文献
15.
D E Boone 《Journal of clinical psychology》1991,47(2):271-276
The relative performance of two Wechsler Adult Intelligence Scale-Revised (WAIS-R) short forms, the Satz-Mogel item reduction technique (Adams, Smigielski, & Jenkins, 1984; Satz & Mogel, 1962) and the Silverstein (1982) subtest-reduction technique, was examined for a group of psychiatric inpatients (N = 75). The two short forms were evaluated on several criteria, including their ability to predict the Full Scale IQ (FSIQ) using regression analysis, their reliability, and their total administration time. The standard error of estimates obtained in predicting the FSIQ were comparable for both short forms and resulted in a +/- 7 confidence interval to achieve 90% accuracy. 相似文献
16.
Monte Carlo methods are used to generate line spread functions describing dose distributions at a variety of depths within a homogeneous water phantom. The line spread function data are convolved with a step function that represents the edge of a primary radiation field. The dosimetric information beyond the edge of the field is reported in the form of tissue-air ratios for three different beam spectra in the diagnostic energy range. 相似文献
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18.
Bruce Minore Margaret Boone Mary Ellen Hill 《Revue canadienne de recherche en sciences infirmières》2004,36(2):148-163
To address a recurring shortage of nurses in the aboriginal communities of Northwestern Ontario, the First Nations and Inuit Health Branch, Health Canada, commissioned a study to explore the viability of establishing a relief pool among nurses from nearby small industrial towns. An open/close-ended survey completed by a random sample of 237 nurses from the target population documented levels of awareness, willingness, and preparedness for northern practice, as well as recruitment incentives and disincentives. Findings demonstrate an awareness of the overlap between the professional and personal dimensions characteristic of such practices, and suggest support for innovative rotations that would cut across federal/provincial/community jurisdictions. Although complex, given time and willingness, a regional relief system seems viable. 相似文献
19.
Peter A. Schneider Peter W. Abcarian Darren Y. Ogawa Jean R. Leduc Philip W. Wright 《Annals of vascular surgery》1997,11(6):574-580
p < 0.01). Cumulative combined primary patency at 1 year by life-table methods was 82 ± 10% in the staged group and 83 ± 9%
in the simultaneous group (p= 0.79). Mean follow-up was 13 ± 6 months. There is a role for balloon angioplasty and stent placement in operative revascularization
of ischemic limbs in selected patients: patency was similar to that produced with the staged approach while the length of
stay was shorter. Intraoperative balloon angioplasty is safe and effective and stents permit a measure of control in assuring
an optimal intraoperative postangioplasty result. 相似文献
20.
Despite awareness that depression may affect performance on commonly used neuropsychological tests, little research has been conducted on the relative impact of severity and type of depression on higher problem-solving ability. Major depressives (n = 13), dysthymics (n = 17), and non-psychiatric comparison subjects (n = 18) were administered the Wisconsin Card Sorting Test (WCST). Although diagnostic category was related only marginally to some WCST measures after controlling for intellectual function, depressive symptom severity emerged as an independent predictor of Total Errors, Perseverative Responses, and Failure to Maintain Set. These findings lend support to the suggestion that neuropsychological test batteries should include assessment for depression and suggest that even relatively mild depression may affect WCST scores. 相似文献