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The PQ-interval was measured while resting supine before exercise testing, in the erect position on the bicycle before starting exercise, and resting supine after exercise in 68 men 6--8 weeks after acute myocardial infarction. During a 6-year follow-up period the death was non-sudden (greater than 1 hour) in 25 of these patients. In this group the PQ-time was significantly shorter (p less than 0.001) during somatomotor activation on the bicycle before exercise than resting supine. The same directional change (p less than 0.01) was seen in the sudden death (less than 1 hour) group (N = 21), but not in the patients who survived. PQ-time at supine rest before exercise testing, however, was significantly shorter (p less than 0.02) in surviving patients than in the non-sudden death group. The possible mechanisms of these, and of previously reported changes in the R-wave amplitudes and QT-times, are discussed. 相似文献
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Sellbom Martin; Ben-Porath Yossef S.; Stafford Kathleen P. 《Canadian Metallurgical Quarterly》2007,19(4):430
We examined the convergent and discriminant validity of the Minnesota Multiphasic Personality Inventory--2 (MMPI--2) measures of psychopathy, including the Clinical Scale 4, Restructured Clinical Scale 4 (RC4), Content Scale Antisocial Practices (ASP), and Personality Psychopathology Five Scale Disconstraint (DISC). Comparisons of the empirical correlates of these scales were conducted with 2 samples of participants evaluated at a criminal court clinic. The 2 samples included 59 men and 19 women and 913 men and 327 women, respectively. Two types of criteria (clinician ratings and archival record review) were utilized in the analyses. Relative to Clinical Scale 4, RC4 had significantly greater convergent validity in predicting psychopathy as measured by the Psychopathy Checklist--Screening Version (S. D. Hart, D. N. Cox, & R. D. Hare, 1995) and behavioral criteria associated with this construct. RC4 also showed substantially improved discriminant validity when compared with its Clinical Scale counterpart. Among all the MMPI-2 scales studied, RC4 was the best measure of the social deviance traits of psychopathy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
75.
J.S. Wright L. Stafford B.P. Gila D.P. Norton S.J. Pearton Hung-Ta Wang F. Ren 《Journal of Electronic Materials》2007,36(4):488-493
The effect of cryogenic temperatures during metal deposition on the contact properties of Pd, Pt, Ti, and Ni on bulk single-crystal
n-type ZnO has been investigated. Deposition at both room and low temperature produced contacts with Ohmic characteristics
for Ti and Ni metallizations. By sharp contrast, both Pd and Pt contacts showed rectifying characteristics after deposition
with barrier heights between 0.37 eV and 0.69 eV. Changes in contact behavior were measured on Pd to anneal temperatures of
∼300 °C, showing an increase in barrier height along with a decrease in ideality factor with increasing annealing temperature.
This difference with annealing temperature is in sharp contrast to previous results for Au contacts to ZnO. There were no
differences in near-surface stoichiometry for the different deposition temperatures; however, low temperature contacts demonstrated
some peeling/cracking for Pt and Pd. 相似文献
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JF Watchko MJ Daood GC Sieck JJ LaBella BT Ameredes AP Koretsky B Wieringa 《Canadian Metallurgical Quarterly》1997,82(5):1416-1423
Creatine kinase (CK) is an enzyme central to cellular high-energy phosphate metabolism in muscle. To characterize the physiological role of CK in respiratory muscle during dynamic contractions, we compared the force-velocity relationships, power, and work output characteristics of the diaphragm (Dia) from mice with combined myofibrillar and sarcomeric mitochondrial CK deficiency (CK[-/-]) with CK-sufficient controls (Ctl). Maximum velocity of shortening was significantly lower in CK[-/-] Dia (14.1 +/- 0.9 Lo/s, where Lo is optimal fiber length) compared with Ctl Dia (17.5 +/- 1.1 Lo/s) (P < 0.01). Maximum power was obtained at 0.4-0.5 tetanic force in both groups; absolute maximum power (2,293 +/- 138 W/m2) and work (201 +/- 9 J/m2) were lower in CK[-/-] Dia compared with Ctl Dia (2,744 +/- 146 W/m2 and 284 +/- 26 J/m2, respectively) (P < 0.05). The ability of CK[-/-] Dia to sustain shortening during repetitive isotonic activation (75 Hz, 330-ms duration repeated each second at 0.4 tetanic force load) was markedly impaired, with CK[-/-] Dia power and work declining to zero by 37 +/- 4 s, compared with 61 +/- 5 s in Ctl Dia. We conclude that combined myofibrillar and sarcomeric mitochondrial CK deficiency profoundly impairs Dia power and work output, underscoring the functional importance of CK during dynamic contractions in skeletal muscle. 相似文献
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