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摘要 目的:评估电针预处理对行下肢关节置换术的老年患者术中血流动力学、术后心血管不良事件、恢复质量的影响。方法:选择择期行下肢关节置换术(膝关节置换或髋关节置换)的老年患者70例,采用随机数字表法分为试验组和对照组。试验组在全麻诱导前30 min于手术准备间予双侧内关、列缺、足三里电针治疗,对照组单纯行全身麻醉。两组全麻诱导后均采用静吸复合麻醉。记录气管插管时(T1)、手术开始后10 min(T2)、拔管后10 min(T3)时的血流动力学参数(HR、MAP、RPP),术后24 h的心血管不良事件、VAS评分、恢复质量(QoR40)的情况。结果:与对照组相比,试验组T1、T2、T3三个时间点的HR、MAP、RPP均明显降低(P<0.05);试验组术后24 h心血管不良事件发生率高于对照组(P<0.05),VAS评分以及术后QoR40比较无差异(P>0.05)。结论:麻醉前电针预处理内关、列缺、足三里可以有效的降低患者心率、血压和心肌氧耗量,降低机体对围术期应激的反应,从而降低围术期不良心血管事件的发生率,提高麻醉的安全和质量。  相似文献   
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Summary Examination of serial semithin sections of rat kidney cortex and a subsequent electron microscopic study of selected areas revealed that the characteristic epithelium of the cortical part of the thick ascending limb of Henle extends for a varying distance beyond the macula densa. The transition from the relatively thin epithelium of the thick ascending limb at this site to the three -or even four-fold thicker epithelium of the convoluted part of the distal tubule is sharply defined and occurs without the interposition of an intermediate cell type.The position of the macula densa at the end but still clearly within the ascending limb of Henle's loop is functionally interpreted to guarantee the separation of the sensor point macula densa from disturbing influences which might arise from the secretory activity of the subsequent tubular portion.Investigations supported by the Deutsche Forschungsgemeinschaft. The skillful technical assistance of Mrs. Saliha Sabanovic is gratefully acknowledged  相似文献   
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Summary Experiments were performed usingin vitro perfused medullary thick ascending limbs of Henle (MTAL) and in suspensions of MTAL tubules isolated from mouse kidney to evaluate the effects of arginine vasopressin (AVP) on the K+ dependence of the apical, furosemide-sensitive Na+:Cl cotransporter and on transport-related oxygen consumption (QO2). In isolated perfused MTAL segments, the rate of cell swelling induced by removing K+ from, and adding onemm ouabain to, the basolateral solution [ouabain(zero-K+)] provided an index to apical cotransporter activity and was used to evaluated the ionic requirements of the apical cotransporter in the presence and absence of AVP. In the absence of AVP cotransporter activity required Na+ and Cl, but not K+, while in the presence of AVP the apical cotransporter required all three ions.86Rb+ uptake into MTAL tubules in suspension was significant only after exposure of tubules to AVP. Moreover,22Na+ uptake was unaffected by extracellular K+ in the absence of AVP while after AVP exposure22Na+ uptake was strictly K+-dependent. The AVP-induced coupling of K+ to the Na+:Cl cotransporter resulted in a doubling in the rate of NaCl absorption without a parallel increase in the rate of cellular22Na+ uptake or transport-related oxygen consumption. These results indicate that arginine vasopressin alters the mode of a loop diuretic-sensitive transporter from Na+:Cl cotransport to Na+:K+:2Cl cotransport in the mouse MTAL with the latter providing a distinct metabolic advantage for sodium transport. A model for AVP action on NaCl absorption by the MTAL is presented and the physiological significance of the coupling of K+ to the apical Na+:Cl cotransporter in the MTAL and of the enhanced metabolic efficiency are discussed.  相似文献   
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Summary The ectodermal-mesenchymal interspace of the chick leg bud was studied at stages leading to the formation of the apical ectodermal ridge (A.E.R.) (stages 14 to 19 HH), using scanning and transmission electron microscopy. The main findings were: 1. a continuous basal lamina under the ectoderm; 2. extracellular fibrils interconnecting the basal lamina and mesenchymal cell processes; 3. an increase in the number of the fibrils during these stages, with the highest number under the A.E.R.; 4. branching mesenchymal cell processes that spread over the basal lamina, making contact with it in all stages. The morphology of the interspace and the changes in it suggest that extracellular material may be significant in the ectodermal-mesenchymal interactions in the limb bud.  相似文献   
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《Current biology : CB》2020,30(11):2191-2195.e3
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