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Three-dimensional electroanatomical mapping (3D EAM) has expanded radiofrequency catheter ablation applications in humans to almost all complex arrhythmias and has drastically reduced fluoroscopy use, yet its potential in dogs is poorly investigated. The objectives of the current study were to assess the feasibility and safety of 3D EAM of all four heart chambers, 3D EAM-guided biopsies and transseptal puncture in dogs. Eight healthy purpose-bred Beagle dogs. Electroanatomical mapping was performed under general anaesthesia during sinus rhythm using a 22-electrode mapping catheter. Left heart catheterisation was achieved by either retrograde transaortic access (n = 4) or transseptal puncture (n = 4). Successful 3D EAM of the right atrium and ventricle was achieved in all dogs at a median time of 33 (13–40) min and 17 (3–52) min, respectively. Left atrial and ventricular 3D EAM was successful in six and seven dogs, at a median time of 17 (4–27) min and 8 min (4–19 min), respectively. Complications requiring intervention occurred in one dog only and were a transient third degree atrioventricular block and pericardial effusion following transseptal puncture, which was treated by pericardiocentesis. All dogs recovered uneventfully. Fluoroscopy time was limited to a median of 7 min (0–45 min) and almost exclusively associated with transseptal puncture. Three-dimensional EAM of all cardiac chambers, including mapping-guided biopsy and transseptal puncture is feasible in small dogs. Complications are similar to those reported in human patients. This suggests a potential added value of 3D EAM to conventional electrophysiology in dogs with arrhythmias. 相似文献
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为明确不同物理介质在橘小实蝇Bactrocera dorsalis幼虫入土、蛆果处理和成虫产卵阻隔等方面的效果,测定橘小实蝇3龄幼虫对果园中4种常用地面阻隔介质的透出率,研究桃果获得位置及腐烂程度、PE塑料袋颜色与幼虫死亡率之间的关系,分析常见成虫阻隔介质材质、厚度、抗穿刺力等指标与果实受害率之间的关系,并对比分析9种常用果袋的田间防控效果。结果表明,无纺布(厚0.16 mm)和PE塑料薄膜(厚0.01 mm)处理24 h均未出现透出现象,可应用于地面覆盖阻止幼虫入土化蛹; PP防草布(厚0.07 mm)和棉毛毡(厚0.27 mm)不建议在橘小实蝇发生区使用。蛆果处理效果与果实获得位置及腐烂程度、PE塑料袋颜色密切相关,以黑色综合效果最好。当纸、PO塑料薄膜和无纺布的厚度分别为≥0.16、0.12和0.20 mm时可实现有效产卵阻隔,此时对应的抗穿刺力值分别为126、86和344 kg/cm2;田间试验结果表明,桃果受害率与果袋材质、厚度、层数及颜色指标有关,双层果袋平均受害率低于单层,但单层白加蜡纸袋整体表现较好且在适当厚度范围内不影响果实着色。 相似文献
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探究四个特色小苹果品种采后生理品质及质地变化规律,为制定特色小苹果最佳贮藏货架期提供科学依据和理论参考。该研究以''龙丰''金红''塞外红''乙女''4个特色小苹果为试验材料,在常温(20±1) ℃条件下放置14 d,测定果实品质指标(硬度、可溶性固形物、可滴定酸、维生素C、乙醇和乙醛含量、乙烯释放量)以及穿刺参数(果肉硬度、果肉做功、破裂力、屈服力)和质地多面分析(Texture Profile Analysis)参数(脆裂性、内聚性、弹性、胶黏性、咀嚼性)等指标的动态变化,并对以上指标进行综合评分。结果表明不同品种小苹果果实的硬度、可滴定酸、维生素C含量随贮藏时间不断下降,可溶性固形物含量变化较小,其中''龙丰''果实硬度、维生素C含量和可滴定酸含量下降均较低,常温贮藏性能优良;''塞外红''刚采收时品质高,但在常温贮藏期间,硬度下降最大,品质下降较快,常温贮藏性能较差。''金红''和''乙女''硬度、维生素C含量下降也较大,且''金红''和''乙女''果实的乙醇、乙醛含量出现峰值,而其他小苹果的乙醇、乙醛含量均大体呈缓慢上升的趋势。不同品种小苹果果实的乙烯释放量呈现先增加后下降的趋势,均出现一个呼吸高峰,''龙丰''乙女''金红''和''塞外红''果实的呼吸高峰出现时间分别是12、6、10和8 d。小苹果果实的穿刺参数和TPA参数均呈现下降趋势,其中''塞外红''果实的穿刺参数和TPA参数在贮藏期间下降速度最快,其次是''金红''和''乙女''果实也呈现较大幅度的下降,而''龙丰''果实则下降最为缓慢。综合评分可知不同品种小苹果常温贮藏性能由高到低依次为''龙丰''金红''乙女''塞外红''。根据常温贮藏期间果实硬度等生理品质并结合果实口感变化,''塞外红''金红''品种的自然贮藏的最佳货架期应为8 d,''龙丰''为12 d,''乙女''为3 d,在以上最佳货架期间,4个品种特色小苹果果实口感保持良好且营养价值损失最低。研究结果为特色小苹果最佳贮藏货架期提供参考。 相似文献