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A new generic code, patterned after and compatible with the NASPE/BPEG Generic Pacemaker Code (NBG Code) was adopted by the NASPE Board of Trustees on January 23, 1993. It was developed by the NASPE Mode Code Committee, including members of the North American Society of Pacing and Electrophysiology (NASPE) and the British Pacing and Electrophysiology Group (BPEG). It is abbreviated as the NBD (for NASPE/BPEG Defibrillator) Code. It is intended for describing the capabilities and operation of implanted cardioverter defibrillators (ICDs) in conversation, record keeping, and device labeling, and incorporates four positions designating: (1) shock location; (2) antitachycardia pacing location; (3) means of tachycardia detection; and (4) antibradycardia pacing location. An additional Short Form, intended only for use in conversation, was defined as a concise means of distinguishing devices capable of shock alone, shock plus antibradycardia pacing, and shock plus antitachycardia and antibradycardia pacing.  相似文献   
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Tip growth of plant cells has been suggested to be regulated by a tip-focused gradient in cytosolic calcium concentration ([Ca2+]c). However, whether this gradient orients apical growth or follows the driving force for this process remains unknown. Using localized photoactivation of the caged calcium ionophore Br-A23187 we have been able to artificially generate an asymmetrical calcium influx across the root hair tip. This led to a change in the direction of tip growth towards the high point of the new [Ca2+]c gradient. Such reorientation of growth was transient and there was a return to the original direction within 15 min. Root hairs forced to change the direction of their growth by placing a mechanical obstacle in their path stopped, reoriented growth to the side, and grew past the mechanical blockage. However, as soon as the growing tip had cleared the obstacle, growth returned to the original direction. Confocal ratio imaging revealed that a tip-focused [Ca2+]c gradient was always centered at the site of active growth. When the root hair changed direction the gradient also reoriented, and when growth returned to the original direction, so did the [Ca2+]c gradient. This normal direction of apical growth of Arabidopsis thaliana (L.) Heynh, root hairs was found to be at a fixed angle from the root of 85 +/- 6.7 degrees. In contrast, Tradescantia virginiana (L.) pollen tubes that were induced to reorient by touch or localized activation of the caged ionophore, did not return to the original growth direction, but continued to elongate in their new orientation. These results suggest that the tip-focused [Ca2+]c gradient is an important factor in localizing growth of the elongating root hair and pollen tube to the apex. However, it is not the primary determinant of the direction of elongation in root hairs, suggesting that other information from the root is acting to continuously reset the growth direction away from the root surface.  相似文献   
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The experimental evaluation of two components of a community intervention to prevent adolescent tobacco use are described. Youth antitobacco activities (e.g., peer quizzes, sidewalk art, poster and T-shirt giveaways, etc.) and family communications activities (pamphlets to parents and student quizzes of parents) were evaluated in two time-series experiments, each of which was conducted in two experimental and one control community. Students in Grades 6 and 8 and their parents were assessed in a series of four phone surveys in the first experiment and six phone surveys in the second. Implementation of the youth antitobacco and family communications activities led to significantly greater exposure of young people to antitobacco information. They led to increases in parent and youth knowledge about tobacco use and more negative attitudes toward tobacco. In Experiment 2, youths in intervention communities had significantly lower rated intentions to smoke. The findings suggest the value of a modular approach to community interventions for influencing the social context relevant to the onset of adolescent tobacco use.  相似文献   
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