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21.
JD Amsterdam F Garcia-Espana J Fawcett FM Quitkin FW Reimherr JF Rosenbaum C Beasley 《Canadian Metallurgical Quarterly》1999,19(1):9-14
PURPOSE: To evaluate the potential diagnostic role of mediastinal sonography in patients with cystic fibrosis (CF), we screened the mediastinum of adult CF patients with and without signs of infection and healthy controls. METHODS: Fifty-four consecutive adult patients with CF and 53 healthy volunteers underwent high-resolution mediastinal sonography. The paratracheal region and aorticopulmonary window of each subject were examined for lymph nodes. Each patient was screened for clinical signs of infection. RESULTS: Lymph nodes were detectable in the mediastinum of 39 of 50 CF patients (78%); the mean total lymph node volume was 1.5 +/- 1.7 cm3. Lymph nodes were detectable in the mediastinum of 31 of 50 controls (62%); the mean total lymph node volume in this group was 0.3 +/- 0.3 cm3 (p < 0.001). In the 30 CF patients with signs of infection, the mean total lymph node volume was larger (2.0 +/- 1.8 cm3) than in the 20 CF patients without signs of infection (0.7 +/- 0.9 cm3; p = 0.002). CONCLUSIONS: These results indicate that lymph node volume determination by high-resolution mediastinal sonography may help assess inflammatory activity in patients with CF. 相似文献
22.
Ciaramelli Elisa; Rosenbaum R. Shayna; Solcz Stephanie; Levine Brian; Moscovitch Morris 《Canadian Metallurgical Quarterly》2010,36(3):619
The ability to navigate in a familiar environment depends on both an intact mental representation of allocentric spatial information and the integrity of systems supporting complementary egocentric representations. Although the hippocampus has been implicated in learning new allocentric spatial information, converging evidence suggests that the posterior parietal cortex (PPC) might support egocentric representations. To date, however, few studies have examined long-standing egocentric representations of environments learned long ago. Here we tested 7 patients with focal lesions in PPC and 12 normal controls in remote spatial memory tasks, including 2 tasks reportedly reliant on allocentric representations (distance and proximity judgments) and 2 tasks reportedly reliant on egocentric representations (landmark sequencing and route navigation; see Rosenbaum, Ziegler, Winocur, Grady, & Moscovitch, 2004). Patients were unimpaired in distance and proximity judgments. In contrast, they all failed in route navigation, and left-lesioned patients also showed marginally impaired performance in landmark sequencing. Patients' subjective experience associated with navigation was impoverished and disembodied compared with that of the controls. These results suggest that PPC is crucial for accessing remote spatial memories within an egocentric reference frame that enables both navigation and reexperiencing. Additionally, PPC was found to be necessary to implement specific aspects of allocentric navigation with high demands on spontaneous retrieval. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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24.
M Fava LA Uebelacker JE Alpert AA Nierenberg JA Pava JF Rosenbaum 《Canadian Metallurgical Quarterly》1997,42(7):568-576
The purpose of this study was to investigate the relationships between depressive subtypes and response to fluoxetine treatment in a large cohort of outpatients. We studied 294 outpatients with major depressive disorder who were then treated with fluoxetine 20 mg/day for 8 weeks. Treatment outcome was evaluated with the Hamilton Depression Rating Scale (HDRS)-17, the Clinical Global Impressions-Severity, and with the HDRS-8; the latter is proposed to be a relatively more specific measure of depression severity than the HDRS-17. We assessed the relationships between degree of treatment response and several depressive subtypes (melancholic, atypical, hostile, and anxious depression, double depression, and depression with comorbid personality disorders), after adjusting for baseline depression severity. We found that nonanxious depressives (patients without any comorbid anxiety disorder) improved slightly but significantly more during treatment than anxious depressives on all outcome measures. Melancholic depression was associated with slightly less improvement on the HDRS-17 only, whereas the other subtypes of depression were not associated with differences in treatment outcome. 相似文献
25.
Kanj R. Rosenbaum E. 《Very Large Scale Integration (VLSI) Systems, IEEE Transactions on》2004,12(9):885-894
Design guidelines for static and domino silicon-on-insulator (SOI) CMOS circuits are evaluated. Restructuring the logic to eliminate gates with large fan-ins is almost as beneficial for SOI as for bulk-silicon. Most published design fixes for eliminating parasitic bipolar induced upset are shown to aggravate the charge sharing problem. A new and improved predischarge method for enhancing the noise tolerance of SOI domino circuits is thus proposed . The topic of multiple output domino logic in SOI technology is addressed for the first time. Multiple output domino logic is shown to be more prone to bipolar leakage induced upset than regular domino. Many of the design practices used to alleviate bipolar leakage in regular domino are no longer valid due to the multiple output domino logic's inherent design requirements. A novel SOI-specific multiple output domino logic, particularly suitable for adder designs, is introduced to minimize the bipolar leakage risk. 相似文献
26.
PR Rosenbaum 《Canadian Metallurgical Quarterly》1997,53(2):556-566
A generalization of Wilcoxon's signed rank test is proposed for testing a dose-response relationship with one or more outcomes. The test is useful in matched observational studies or in nonrandomized experiments that use dose-response relationships and predictions about multiple outcomes in an effort to distinguish actual treatment effects from hidden biases. A sensitivity analysis indicating whether a dose-response relationship or multiple predictions are confirmed with sufficient strength to reduce sensitivity to hidden bias is performed. Together, the test and the sensitivity analysis help to quantify the degree to which a coherent pattern of associations is present or absent, and the degree to which this strengthens or fails to strengthen evidence of cause and effect. Formal properties of tests of this kind are examined. The form of the optimal test is determined, though this test is not usable because it depends upon the values of the unknown parameters under study. Also examined are the conditions under which the proposed test resembles the optimal test, as well as the impact of various violations of those conditions on power. An example involving matched pairs exposed to varying doses of cadmium is considered in detail. 相似文献
27.
In this article I reply to a comment made by S. J. Guastello (see record 2006-00920-013) on my original article, "The Cinderella of Psychology: The Neglect of Motor Control in the Science of Mental Life and Behavior" (see record 2005-05480-002). In my article, I asked why motor control has received short shrift in psychology. I observed that it is ironic that motor control has long had the status of a Cinderella in psychological research given that the main question in motor control is, arguably, the same as the main question in psychology: How do behaviors originate? I offered seven hypotheses for psychology's neglect of motor control. Guastello suggested that these seven hypotheses should be supplanted by three others: (a) the division-of-labor hypothesis, (b) the dumb-experiment hypothesis, and (c) the critical-concepts-were-not-available-until-recently hypothesis. Here I ask, Who is right and does it matter? (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
28.
Spencer L. Tomarken Daniel M. Silevitch Gabriel Aeppli Braden A.W. Brinkman Jian Xu Karin A. Dahmen Thomas F. Rosenbaum 《Advanced functional materials》2014,24(20):2986-2992
Random magnetic fields, varying from site to site in a magnetic material, are a form of disorder that can determine the local architecture and stability of the magnetic state. In a ferromagnet, the application of an external magnetic field can amplify the effects of the internal random fields and, in principle, harden a magnetic domain, without changing temperature and only for as long as the external field is present. Here, the rare‐earth compound Nd2Fe14B, formed with a granular morphology of random‐packed, elongated grains, is an experimental realization of the Random Field Ising Model in a room temperature ferromagnet. The application of magnetic fields transverse to the easy axis tunes the coupling between the structural disorder and the magnetic pinning properties. This material both illuminates the intricacies of tunable disorder and serves as a guidepost along the way to developing increased‐density magnetic storage media. 相似文献
29.
O'Leary K. Daniel; Barling Julian; Arias Ileana; Rosenbaum Alan; Malone Jean; Tyree Andrea 《Canadian Metallurgical Quarterly》1989,57(2):263
Community couples (N?=?272) were assessed in a longitudinal study of early marriage. More women than men reported physically aggressing against their partners at premarriage (44% vs. 31%) and 18 months (36% vs. 27%). At 30 months, men and women did not report significantly different rates of aggression (32% vs. 25%). However, using either the self-report or the partner's report, the prevalence of aggression for both men and women were pushing, shoving, and slapping. Conditional probability analyses indicated that the likelihood of physically aggressing at 30 months given that one had engaged in such aggression before marriage and at 18 months after marriage was .72 for women and .59 for men. Furthermore, 25–30% of the recipients of physical aggression at all three assessment periods were seriously maritally discordant at 30 months. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
30.
BACKGROUND: Previously, we have shown that a premature stimulus can significantly modulate spatial gradients of ventricular repolarization (ie, modulated dispersion), which result from heterogeneous electrophysiological properties between cells. The role modulated dispersion may play in determining electrical instability in the heart is unknown. METHODS AND RESULTS: To determine if premature stimulus-induced changes in repolarization are a mechanism that governs susceptibility to cardiac arrhythmias, optical action potentials were recorded simultaneously from 128 ventricular sites (1 cm2) in 8 Langendorff-perfused guinea pig hearts. After baseline pacing (S1), a single premature stimulus (S2) was introduced over a range of S1S2 coupling intervals. Arrhythmia vulnerability after each premature stimulus was determined by measurement of a modified ventricular fibrillation threshold (VFT) during the T wave of each S2 beat (ie, S2-VFT). As the S1S2 interval was shortened to an intermediate value, spatial gradients of repolarization and vulnerability to fibrillation decreased by 51+/-9% (mean+/-SEM) and 73+/-45%, respectively, compared with baseline levels. As the S1S2 interval was further shortened, repolarization gradients increased above baseline levels by 54+/-30%, which was paralleled by a corresponding increase (37+/-8%) in vulnerability. CONCLUSIONS: These data demonstrate that modulation of repolarization gradients by a single premature stimulus significantly influences vulnerability to ventricular fibrillation. This may represent a novel mechanism for the formation of arrhythmogenic substrates during premature stimulation of the heart. 相似文献