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41.
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
42.
摘要 目的:探讨超声引导下隐神经联合腘动脉与膝关节后囊间隙(IPACK)阻滞对老年全膝关节置换术(TKA)患者应激反应、炎性细胞因子及膝关节活动度的影响。方法:根据随机数字表法,将无锡市中医医院2021年3月~2022年9月期间收治的102例初次行TKA的老年患者分为观察组(超声引导下隐神经联合IPACK阻滞镇痛处理)和对照组(超声引导下隐神经镇痛处理),每组各51例。对比两组疼痛情况、炎性细胞因子、应激反应指标、不良反应发生率、膝关节活动度。结果:观察组术后6 h、术后12 h、术后24 h视觉模拟评分法(VAS)评分低于对照组(P<0.05)。观察组术后48 h肿瘤坏死因子-α(TNF-α)、白细胞介素(IL)-6、IL-1β、β-淀粉样蛋白(Aβ)低于对照组(P<0.05)。观察组术后48 h血管紧张素Ⅱ(AngⅡ)、皮质醇(COR)低于对照组(P<0.05)。观察组术后24 h、术后48 h膝关节活动度大于对照组(P<0.05)。两组不良反应发生率对比无差异(P>0.05)。结论:超声引导下隐神经联合IPACK阻滞用于TKA患者,具有较好的镇痛效果,可减轻应激反应,抑制炎性细胞因子过度分泌,改善膝关节活动度,麻醉效果较好。 相似文献
43.
M. Tertuliano D.M. Olson G.C. Rains & W.J. Lewis 《Entomologia Experimentalis et Applicata》2004,110(2):165-172
Microplitis croceipes (Cresson) (Hymenoptera: Braconidae) learns odors in association with both hosts and food. The food‐associated ‘seeking’ behavior of M. croceipes was investigated under various training protocols utilizing the conditioning odor, 3‐octanone. We investigated the effects of odor training, or its lack, training duration, training frequency, time elapsed after training, wasp hunger state, and training reinforcement, on the food‐seeking responses of M. croceipes females. We found that odor‐trained females show strong food seeking responses, whereas non‐odor‐trained females do not respond to the odor, and that a single 10 s association with the odor whilst feeding on sugar water subsequently conditioned the wasps to exhibiting significant responses to it. Increases in training time to more than 10 s did not improve their responses. Repetition of the food–odor associations increased a wasp's recall, as well as its response over time, compared to a single exposure. Repeated exposure to the learned odor in the absence of a food reward decreased the responses of less hungry individuals. However, the level of response increased significantly following a single reinforcement with the food–odor association. Understanding the factors that influence learning in parasitoids can enhance our ability to predict their foraging behavior, and opens up avenues for the development of effective biological detectors. 相似文献
44.
Brassinosteroid-induced rice lamina joint inclination and its relation to indole-3-acetic acid and ethylene 总被引:1,自引:0,他引:1
Brassinosteroid (BR)-induced rice (Oriza sativa L.) lamina joint (RLJ) inclination and its relationship to indole-3-acetic acid (IAA) and ethylene were investigated using BR isolated from beeswax. The effect of BR on RLJ inclination was time- and concentration-dependent. Etiolated lamina were more sensitive to BR than green lamina. The BR-induced inclination was accompanied by increased lamina fresh weight, total water content, free-water content, proton extrusion and ethylene production, and decreased bound-water content. Lamina dry weight was not changed. The inclination was due to greater expansion of the adaxial cells relative to the dorsal cells in the lamina joint. This response was caused by BR and/or BR-induced signal(s) that were transported from the leaf sheath to the leaf blade. Both BR-induced RLJ inclination and ethylene production were inhibited by cobalt chloride (CoCl2), an inhibitor of ACC oxidase. BR-induced inclination was much higher than that of IAA, and was inhibited by high concentration of 2,3,5-triiodobenzoic acid (TIBA), an inhibitor of IAA transport. A synergistic effect was observed between BR and IAA. These results suggest that the effects of BR on RLJ inclination and pulvinus cell expansion may be resulted from BR-increased water potential and proton extrusion in the lamina. The BR-induced RLJ inclination may involve the action of ethylene but may be independent of IAA.Abbreviations BR
brassinolide or brassinosteroid(s)
- IAA
indole-3-acetic acid
- TIBA
2,3,5-triiodobenzoic acid
- RLJ
rice lamina joint 相似文献
45.
运动延缓脑衰老的实验研究 总被引:4,自引:0,他引:4
运动是延缓脑衰老的重要手段之一。以“跑转笼”方式建立运动动物模型,用行为学、形态学和生物学研究方法,研究从青年开始的长期运动(8mo,19mo)对运动相关中枢随年龄增加而出现的退行性变化的作用及作用机制。结果表明,长期适量运动能够延缓运动相关中枢随年龄增加而出现的形态结构和功能的退行性变化,通过促进神经元结构代偿而改善神经元功能。 相似文献
46.
47.
Familial phenotypic resemblance for six quantitative neuromuscular performance traits is analyzed by path analysis using data from the Mennonite community of Goessel, Kansas. Of the six traits only one, dominant hand strength, shows no evidence of parent-offspring transmission (t2 = 0.001) and only one, trunk flexibility, shows evidence of a high degree of transmissibility (t2 = 0.662). The four remaining traits display low to moderate levels of transmissibility (t2 = 0.073 to t2 = 0.245). A substantial residual sibling resemblance due to shared environmental effects is seen for all six traits. It is suggested that the high heritabilities found for many of these traits by other methods result from the inability of these methods to account for the shared nongenetic effects. 相似文献
48.
49.
The use of a partition locus to increase stability of tryptophan-operon-bearing plasmids in Escherichia coli 总被引:6,自引:0,他引:6
The stability of different derivatives of plasmid vectors pBR322 and pACYC184 carrying the tryptophan operon of Escherichia coli was monitored in various media. It was found that in the absence of any special selective pressure, all plasmids were lost from the culture. The stability varied depending both on the orientation of the inserted tryptophan fragment and the growth media used. The pBR322::trp+ plasmids were lost at an average frequency of 0.3 to 0.8% per cell generation, while the pACYC184::trp+ plasmid was lost at a rate higher than 5%. In all cases the whole plasmid was lost at a rate higher than 5%. In all cases the whole plasmid was lost, indicating a high stability of the plasmid::cloned DNA as such. To increase the stability of the cloning vectors, the partition locus of plasmid pSC101 was added to both the pBR322::trp+ and pACYC184::trp+ plasmids. The addition of this gene increased the replicon stability at least 3- to 10-fold, with the pBR322::trp+-par+ plasmids being the most stable. Also in this case, the stability was dependent on the plasmid type and on the growth medium. In no case was there a discoordinate loss of the antibiotic-resistance and tryptophan genes from the vectors. 相似文献
50.
Francis L. Marcrina R.Paul Evans Janet Ash Tobian Donna L. Hartley Don B. Clewell Kevin R. Jones 《Gene》1983,25(1):145-150
A novel plasmid vector that is able to replicate both in Escherichia coli and in Streptococcus sanguis is described. This 9.2-kb plasmid, designated pVA856, carries Cmr, Tcr and Emr determinants that are expressed in E. coli. Only the Emr determinant is expressed in S. sanguis. Both the Cmr and the Tcr of pVA856 may be insertionally inactivated. This plasmid affords several different cleavage-ligation strategies for cloning in E. coli followed by subsequent introduction of chimeras in to S. sanguis. In addition, we have modified a previously described E. coli-S. sanguis shuttle plasmid [pVA838; Macrina et al., Gene 19 (1982) 345–353], so that it is unable to replicate in S. sanguis. The utility of such a plasmid for cloning and selecting sequences enabling autonomous replication in S. sanguis is demonstrated. 相似文献