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Keenan-Miller Danielle; Hammen Constance; Brennan Patricia A. 《Canadian Metallurgical Quarterly》2010,119(4):836
The current article explores the connection between maternal depression and offspring aggression during the transition to adulthood, expanding the scope of prior research on this topic. Both family-level factors (including parent–child relationship quality and maternal romantic relationship quality) and youth factors (including depression history and social functioning in midadolescence) were tested as potential mediators in a longitudinal community sample of 710 youth at ages 15 and 20. The results suggest that maternal depression confers a risk for higher levels of aggressive behavior by offspring at age 20. Structural equation models suggested that the association between maternal depression and youth aggression is fully mediated by youth history of depression by midadolescence, even when accounting for the stability of aggression between ages 15 and 20. Parent–child relationship quality, youth social functioning, and maternal relationship quality were not unique mediators of this association. Limitations and implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Brennan Penny L.; Schutte Kathleen K.; Moos Rudolf H. 《Canadian Metallurgical Quarterly》2006,13(3):253
At 1 year, 4 years, and 10 years after baseline, late-middle-aged adults reported whether they had successfully resolved their most important stressor of the past year. Compared to individuals who never resolved focal stressors over the 10-year interval, those who always did consistently showed less negative stressor appraisal, less reliance on avoidance coping, and less use of exploratory relative to directed coping responses, independent of type and severity of focal stressor. Less use of exploratory relative to directed coping and having more social resources, fewer health problems, and fewer depressive symptoms at baseline predicted more stressor resolution over the next 10 years. These predictors are promising foci for prospective efforts to optimize ways in which aging adults manage late-life stressors. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Linda L. Brennan 《Canadian Metallurgical Quarterly》2006,22(3):98-107
While acknowledging the difficulties of managing professionals, many theorists and practitioners are critical of applying operations management practices as solutions. This study challenges these criticisms by developing a series of propositions for engineering consulting firms based on a flexible manufacturing paradigm, in particular to (1) develop a generalized skill set among employees; (2) balance the workload across the organization; (3) cultivate project managers in a deliberate manner; and (4) apply operational models to predict the impact of resource allocation schemes. These propositions are examined in the context of a case study of engineers and technicians in a consulting company. The exploratory data analysis supports the validity of the propositions and also indicates the need for other operational improvements. 相似文献
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RG Grabitz F Freudenthal M Sigler TP Le C Boosfeld S Handt G von Bernuth 《Canadian Metallurgical Quarterly》1998,31(3):677-683
Glyceraldehyde-3-phosphate dehydrogenase (G3PDH) is often used as a control gene for mRNA expression, however it has been proposed to be overexpressed in all hepatocellular carcinomas (HCC). Equal amounts of tumor and paired normal (T/N) RNA, based on OD260/280 nm, were compared using ethidium bromide staining, poly-T probing, gene-specific dot blot and Northern blots using control probes G3PDH, actin and histone H4. Using mRNA blots 13/20 surgical HCC pairs did not overexpress G3PDH. Those 7/20 intact samples which did appear to overexpress G3PDH on Northern blot could not be detected by poly-T probing of dot blots. The apparent overexpression was not specific for the control gene G3PDH nor for the malignancy HCC. It may represent partial mRNA degradation, or the presence of as yet unknown substances which interfere with absorption at 260/280 nm. We advise caution in selecting human T/N pairs for differential gene expression studies. For HCC, no clinicopathological variables, including cirrhosis, predicted whether a T/N sample pair was likely to be balanced or not. 相似文献
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MT Manley WN Capello JA D''Antonio AA Edidin RG Geesink 《Canadian Metallurgical Quarterly》1998,80(8):1175-1185
OBJECTIVE: To investigate the roles of brain angiotensin II and C-type natriuretic peptide (CNP) in the hypertensive mechanism of deoxycorticosterone acetate (DOCA)-salt hypertension. METHODS: We injected 50 microg/kg CV-11 974, an angiotensin II type-1 receptors antagonist, 30 nmol/kg CNP-22, or the vehicle (artificial cerebrospinal fluid) into the cerebral ventricle or intravenously 5 min before the intracerebroventricular infusion of 1.5 mol/I NaCl solution for 30 min into either male normotensive Wistar rats or DOCA-salt hypertensive rats anesthetized with urethane, and their arterial pressures and heart rates were continuously recorded. Blood (2 ml) was collected at the end of the infusion for the measurement of plasma concentration of arginine vasopressin. We infused 10 or 50 microg/kg per day CV-11 974, 10 or 50 nmol/kg per day CNP-22, or the vehicle (1 microl/h) into the cerebral ventricles of DOCA-salt hypertensive rats for 7 days by using osmotic minipumps, and measured their systolic arterial pressures, pulse rates, and urinary excretions of vasopressin. RESULTS: Intracerebroventricular pre-administrations of CV-11 974 and of CNP-22 inhibited increases in mean arterial pressure, heart rate, and plasma vasopressin concentration induced by intracerebroventricular infusion of 1.5 mol/l NaCl into normotensive rats; increases in hemodynamics and plasma level of vasopressin induced by intracerebroventricular infusion of 1.5 mol/l NaCl were suppressed by intracerebroventricular pre-injections of CV-11 974, but not of CNP-22, into DOCA-salt hypertensive rats. Continuous intracerebroventricular infusions of 50 microg/kg per day CV-11 974 attenuated hypertension in DOCA-salt treated rats, accompanied by a reduction in urinary excretion of vasopressin. Continuous intracerebroventricular infusions of 50 nmol/kg per day CNP-22, however, affected neither hypertension nor urinary excretion of vasopressin in DOCA-salt hypertensive rats. CONCLUSION: Brain angiotensin II could play a role in the pressor mechanism of DOCA-salt hypertension by increasing release of vasopressin via type 1 receptors. That brain CNP has an inhibitory effect on release of vasopressin in acute experiments indicates that the impairment of this inhibitory effect of brain CNP on secretion of vasopressin could be involved in the pathogenesis of DOCA-salt hypertension in rats. 相似文献
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A 54 year-old man had symptoms of acute right hemispheric cerebral ischemia. He was initially considered for participation in a trial of early thrombolysis in stroke, but an innominate artery embolus was found with no apparent arterial source. The embolus was removed by means of a combined brachial and carotid bifurcation approach to protect the cerebral vasculature from embolic fragmentation during extraction. Further investigation revealed deep venous thrombosis, evidence of pulmonary emboli, and a patent foramen ovale, supporting a diagnosis of paradoxic embolus. Additional treatment included anticoagulation and placement of an inferior vena caval filter. The unusual condition of paradoxic embolus is reviewed, and the management of this patient is discussed. 相似文献