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The functional development of cardiac and adrenal medullary responses to reflex activation of the sympathetic nervous system was studied in preweanling spontaneously hypertensive (SHR) and Wistar-Kyoto (WKY) normotensive rats. Pups of the two strains received injections of insulin or saline at 2, 4, 8, 12, or 16 days of age and were sacrificed 3 h later. Insulin administration produces a significant decrease in circulating levels of glucose which in turn results in a centrally mediated increase in sympathetic outflow. The induction of ornithine decarboxylase (ODC) in heart and the depletion of epinephrine from the adrenal medulla served as tissue markers of functional sympathetic neurotransmission. WKY and SHR pups had comparable levels of ODC activity in heart under basal conditions. In contrast, levels of catecholamines in the adrenals were greater in SHR pups at 2 and 4 days of age. Following insulin administration, SHR pups exhibited a greater induction of cardiac ODC activity at 2, 4, and 8 days of age compared to age-matched WKY controls. However, there were no differences between SHR and WKY pups in the magnitude of the adrenal medullary response to insulin-induced hypoglycemia. These alterations in sympathetic-target tissue development during the first postnatal week of life may contribute in part to the higher arterial pressures maintained by SHRs throughout the lifespan.  相似文献   
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Let S be a deductive system such that S-derivability (s) is arithmetic and sound with respect to structures of class K. From simple conditions on K and s, it follows constructively that the K-completeness of s implies MP(S), a form of Markov's Principle. If s is undecidable then MP(S) is independent of first-order Heyting arithmetic. Also, if s is undecidable and the S proof relation is decidable, then MP(S) is independent of second-order Heyting arithmetic, HAS. Lastly, when s is many-one complete, MP(S) implies the usual Markov's Principle MP.An immediate corollary is that the Tarski, Beth and Kripke weak completeness theorems for the negative fragment of intuitionistic predicate logic are unobtainable in HAS. Second, each of these: weak completeness for classical predicate logic, weak completeness for the negative fragment of intuitionistic predicate logic and strong completeness for sentential logic implics MP. Beth and Kripke completeness for intuitionistic predicate or sentential logic also entail MP.These results give extensions of the theorem of Gödel and Kreisel (in [4]) that completeness for pure intuitionistic predicate logic requires MP. The assumptions of Gödel and Kreisel's original proof included the Axiom of Dependent Choice and Herbrand's Theorem, no use of which is explicit in the present article.  相似文献   
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Spontaneously hypertensive (SHR), Wistar-Kyoto (WKY) normotensive, and Sprague-Dawley (SD) normotensive rats were either reared by their natural mothers (controls) or fostered to a mother of one of the other strains. The effects of rearing environment were assessed by measures of body weight at weaning and adult resting mean arterial blood pressure (MAP) and heart rate (HR). At weaning, SHR control rats weighed less than WKY controls which in turn weighed less than SD controls. SHR and WKY rats reared by SD mothers weighed significantly more than their respective controls, whereas SD rats reared by either SHR or WKY mothers weighed less than SD control rats. Manipulation of the maternal environment was attended by a change in adult resting MAP in only one group. SHR rats reared by SD mothers had MAPs which were significantly lower than SHRs reared by their natural mothers. No within-strain adult HR differences were observed between control and cross-fostered groups. These data indicate that the effects of cross-fostering on adult resting MAP previously reported for SHR and WKY animals are generalizable to another normotensive strain. That is, genetically hypertensive (SHR) animals exposed to a normotensive (WKY or SD) maternal environment display a reduction in adult resting MAP, whereas hypertension or an increase in adult MAP is not induced in normotensive rats (WKY or SD) as a consequence of exposure to a hypertensive maternal environment.  相似文献   
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The role of visual input during reaching and grasping was evaluated. Groups of infants (5, 7, and 9 months old) and adults reached for an illuminated object that sometimes darkened during the reach. Behavioral and kinematic measures were assessed during transport and grasp. Both infants and adults could complete a reach and grasp to a darkened object. However, vision was used during the reach when the object remained visible. Infants contacted the object more often when it remained visible, though they had longer durations and more movement units. In contrast, adults reached faster and more precisely during transport and grasp when the object remained visible. Thus, continuous sight of the object was not necessary, but when it was available, infants used it for contacting the object whereas adults used it to reach and grasp more efficiently.  相似文献   
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Many medical institutions have converted to a digital model for record keeping due to the Health Information Technology for Economic and Clinical Health Act. This Act provides incentives to health care systems to accelerate and encourage the adoption of electronic health record (EHR) systems. The pedigree as a tool in medicine provides an efficient method to assess and represent an individual’s health and family health risks that may otherwise not be apparent in the medical record in a clearly identifiable way (Schuette, J. L., & Bennett 2009). Many clinicians continue to construct pedigrees using pen and paper method despite findings of improved identification of at risk patients with similar electronic intake tools (Arar et al. in Personalized Medicine 2011 8:523–32). The goal of this study was to explore the patient and practitioner experience with electronic pedigree programs using Proband, an application developed at The Children’s Hospital of Philadelphia for genetic counselors to construct pedigrees during genetic counseling sessions directly on iPads. The first part of this study looked at the patient experience and assessed time to take the pedigree and the impact of using an electronic pedigree tool on the relationship between participant and genetic counselor. This involved 50 participants and was compared with the traditional paper method of taking a pedigree. There was no statistical significance found between the two different mediums in accuracy, speed, and rapport with provider. The second part of the study assessed the usability of Proband by ten genetic counselors. Overall, the application received a system usability score of 90/100 with a majority (7/10) of counselors agreeing that they would use this application in their clinic. The positive outcome of this study encourages future work to assess the impact and usability of programs on a larger scale as they continue to integrate into current electronic health records.  相似文献   
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Serious sequelae of youth depression, plus recent concerns over medication safety, prompt growing interest in the effects of youth psychotherapy. In previous meta-analyses, effect sizes (ESs) have averaged .99, well above conventional standards for a large effect and well above mean ES for other conditions. The authors applied rigorous analytic methods to the largest study sample to date and found a mean ES of .34, not superior but significantly inferior to mean ES for other conditions. Cognitive treatments (e.g., cognitive-behavioral therapy) fared no better than noncognitive approaches. Effects showed both generality (anxiety was reduced) and specificity (externalizing problems were not), plus short- but not long-term holding power. Youth depression treatments appear to produce effects that are significant but modest in their strength, breadth, and durability.  相似文献   
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Most studies of adolescent substance use and psychological comorbidity have examined the contributions of conduct problems and depressive symptoms measured only at particular points-in-time. Yet, during adolescence, risk factors such as conduct problems and depression exist within a developmental context, and vary over time. Though internalizing and comorbid pathways to substance use have been theorized (Hussong et al. Psychology of Addictive Behaviors 25:390-404, 2011), the degree to which developmental increases in depressive symptoms and conduct problems elevate risk for substance use impairment among adolescents, in either an additive or potentially a synergistic fashion, is unclear. Using a school-based sample of 521 adolescents, we tested additive and synergistic influences of changes in depressive symptoms and conduct problems from 6th to 9th grade using parallel process growth curve modeling with latent interactions in the prediction of late adolescent (12th grade) substance use impairment, while examining gender as a moderator. We found that the interaction between growth in depression and conduct disorder symptoms uniquely predicted later substance use problems, in addition to main effects of each, across boys and girls. Results indicated that adolescents whose parents reported increases in both depression and conduct disorder symptoms from 6th to 9th grade reported the most substance use-related impairment in 12th grade. The current study demonstrates that patterns of depression and conduct problems (e.g., growth vs. decreasing) are likely more important than the static levels at any particular point-in-time in relation to substance use risk.  相似文献   
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