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71.
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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Bougienage was made in 625 patients with burn strictures of the esophague which made up 59.4% of all patients (1053) who have undergone treatment since 1966 to October 1977 in Research Center of Surgery. Indications and contraindications for bougienage are discussed. In patients with short strictures (146) good effect was obtained in 83.1% of cases, in long strictures (803) the bougienage was effective in 61.1% of patients, in total strictures (104) good and favourable results were obtained in 26.2% of cases. Bougienage is an important method of treatment for patients with burn strictures of the esophagus, as well as a method of preoperative preparation.  相似文献   
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BACKGROUND: Varicella infection causes substantial morbidity in young adults. Most military basic trainees are 18 to 21 years old, yet the Army has no varicella vaccination policy. We therefore determined varicella susceptibility in a population of Army basic trainees, examined variables that might predict antibody status, and developed a vaccination strategies model. METHODS: Fifteen-hundred ninety-five trainees completed a demographic and historical questionnaire. Varicella antibody status was determined on 1201 volunteers. These data plus information from the literature were used to construct a decision tree of vaccination strategies that was applied to the total population of Army basic trainees in 1995 (n = 65,298). RESULTS: Fifty (4.2 percent) of 1201 soldiers were antibody negative. Trainees who lived with no or 1 sibling while growing up were most likely to be seronegative (P < 0.01). The positive predictive value of a history of varicella was 98.5 percent, whereas the negative predictive value of a negative history of varicella was 23 percent. In the vaccination strategies model, serologically testing soldiers with a negative history of varicella and vaccinating those without protective antibodies was the most cost-effective approach. CONCLUSIONS: In young adults a positive varicella history accurately predicts immunity, but verification of a negative history with antibody testing is recommended before vaccination.  相似文献   
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