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Stellate ganglion (SG) modification has been investigated for arrhythmia treatment. In this study, transesophageal SG imaging and intervention were explored using a homemade 30F integrated focused ultrasonic catheter in healthy mongrel canines in vivo. Anatomic details of SGs were ultrasonically imaged and evaluated. SG had a heterogeneous echoic structure and characteristic profiles sketched by hyper-echoic outlines in an ultrasonogram. Left SGs in the experimental group were successfully ablated through the esophagus under ultrasonic guidance provided by the catheter itself. Two weeks after the ablation, the QT and QTc of the experimental group decreased compared with those of the sham group and at baseline (both p values < 0.001). Histologic examination revealed that left SGs were destroyed. No major complications were observed. This approach may be further explored as a method for ganglia remodeling evaluation and as a strategy of ganglia modification for arrhythmia and for other diseases.  相似文献   
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艾灸作为中医学最古老的疗法之一,作用多样,应用广泛,疗效显著。随着科技的发展,人们对灸法的认识逐渐深入,其中艾烟的相关研究也硕果累累,其安全性广受关注。通过对艾烟作用和安全性评价研究中取得的成果进行归纳分析,以期为艾灸临床安全应用提供指导。  相似文献   
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Objectives

Short successive periods of skeletal muscle disuse have been suggested to substantially contribute to the observed loss of skeletal muscle mass over the life span. Hospitalization of older individuals due to acute illness, injury, or major surgery generally results in a mean hospital stay of 5 to 7 days, during which the level of physical activity is strongly reduced. We hypothesized that hospitalization following elective total hip arthroplasty is accompanied by substantial leg muscle atrophy in older men and women.

Design and participants

Twenty-six older patients (75 ± 1 years) undergoing elective total hip arthroplasty participated in this observational study.

Measurements

On hospital admission and on the day of discharge, computed tomographic (CT) scans were performed to assess muscle cross-sectional area (CSA) of both legs. During surgery and on the day of hospital discharge, a skeletal muscle biopsy was taken from the m. vastus lateralis of the operated leg to assess muscle fiber type–specific CSA.

Results

An average of 5.6 ± 0.3 days of hospitalization resulted in a significant decline in quadriceps (?3.4% ± 1.0%) and thigh muscle CSA (?4.2% ± 1.1%) in the nonoperated leg (P < .05). Edema resulted in a 10.3% ± 1.7% increase in leg CSA in the operated leg (P < .05). At hospital admission, muscle fiber CSA was smaller in the type II vs type I fibers (3326 ± 253 μm2 vs 4075 ± 279 μm2, respectively; P < .05). During hospitalization, type I and II muscle fiber CSA tended to increase, likely due to edema in the operated leg (P = .10).

Conclusions

Six days of hospitalization following elective total hip arthroplasty leads to substantial leg muscle atrophy in older patients. Effective intervention strategies are warranted to prevent the loss of muscle mass induced by short periods of muscle disuse during hospitalization.  相似文献   
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目的:探索原肌球蛋白4(Tropomyosin4,TPM4)在胃癌细胞的迁移、侵袭和转移中的作用。方法:利用Real-time PCR、Western Blot及免疫荧光,检测原肌球蛋白4在不同胃癌细胞系及正常胃上皮细胞中的表达情况;利用免疫组化,检测原肌球蛋白4在胃癌组织及癌旁正常组织中的表达情况;利用慢病毒技术,在GC9811-P细胞中,分别转染LV-TPM4、shRNA-TPM4及对照空载体;通过Transwell和体内实验,检测胃癌细胞迁移、侵袭和转移。结果:Real-time PCR、Western Blot及免疫组化结果显示,原肌球蛋白4在胃癌细胞系及胃癌组织中的表达降低;上调原肌球蛋白4的表达后,抑制胃癌细胞的迁移、侵袭和转移;下调原肌球蛋白4的表达后,促进胃癌细胞的迁移、侵袭和转移(P<0.05)。结论:原肌球蛋白4抑制胃癌细胞的迁移、侵袭和转移。  相似文献   
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目的:系统评价沙利度胺(thalidomide,TLD)联合肝动脉化疗栓塞术(transcatheter arterial chemoembolization,TACE)治疗原发性肝癌(primary hepatic carcinomas,PHC)的疗效和安全性.方法:计算机检索Cochrane Library(2014年第3期)、Web of Science(1986/2014-03)、Pub Med(1966/2014-03)、CNKI(1917/2014-03)、维普(1989/2014-03)、万方数据库(1998/2014-03),收集所有TLD联合TACE治疗PHC的随机对照试验.由两名评价员严格按照纳入标准选择文献,提取资料,并参照Cochrane系统评价的要求,对选择纳入的随机对照试验进行方法学质量评估后,采用Cochrane协作网提供的Rev Man 5.2软件对总有效率、疾病控制率、生活质量KPS评分、不同年限生存率、甲胎蛋白的变化、血管内皮生长因子(vascular endothelial growth factor,VEGF)的变化及不良反应发生率进行Meta分析.结果:最终纳入22项随机对照试验,包括1590例PHC患者,Meta分析结果显示,TLD联合TA C E组治疗P H C的总有效率(R R合并=1.29,95%C I:1.15-1.44)、疾病控制率(R R合并=1.27,95%CI:1.16-1.39)、生活质量KPS评分(MD合并=9.23,95%CI:6.90-11.55)、半年生存率(RR合并=1.10,95%C I:1.01-1.20)、1年生存率(RR合并=1.25,95%C I:1.13-1.39)、2年生存率(RR合并=1.45,95%CI:1.18-1.78)、3年生存率(R R合并=1.7 0,9 5%C I:1.1 6-2.5 0)、V E G F水平的变化(M D合并=-123.64,95%C I:-143.72--103.55)优于单纯TACE组,差异有统计学意义(均P0.05);不良反应发生率:在药物性皮疹发生率方面,TLD联合TACE组明显高于单纯TACE组,差异有统计学意义(RR=4.50,95%CI:2.34-8.64,P0.00001);在减少消化系应发生率(RR=1.08,95%CI:0.93-1.25)、降低骨髓抑制发生率(RR=1.12,95%CI:0.82-1.52)、降低肝功能异常发生率方面(R R=1.00,95%C I:0.72-1.39),T L D联合TA C E组与单纯TA C E组相近似,差异无统计学意义(均P0.05).结论:目前研究显示,与单纯TACE疗法相比,TLD联合TACE治疗PHC在总有效率、疾病控制率、生活质量KPS评分、半年生存率、1、2、3年生存率、降低V E G F方面具有明显的优势,但在安全性方面,TLD联合TACE组在药物性皮疹发生率方面明显高于单纯TACE组,而在消化系反应、骨髓抑制率、肝功能异常方面与单纯TACE组相似.  相似文献   
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The developing CNS is exposed to physiological hypoxia, under which hypoxia-inducible factor α (HIFα) is stabilized and plays a crucial role in regulating neural development. The cellular and molecular mechanisms of HIFα in developmental myelination remain incompletely understood. A previous concept proposes that HIFα regulates CNS developmental myelination by activating the autocrine Wnt/β-catenin signaling in oligodendrocyte progenitor cells (OPCs). Here, by analyzing a battery of genetic mice of both sexes, we presented in vivo evidence supporting an alternative understanding of oligodendroglial HIFα-regulated developmental myelination. At the cellular level, we found that HIFα was required for developmental myelination by transiently controlling upstream OPC differentiation but not downstream oligodendrocyte maturation and that HIFα dysregulation in OPCs but not oligodendrocytes disturbed normal developmental myelination. We demonstrated that HIFα played a minor, if any, role in regulating canonical Wnt signaling in the oligodendroglial lineage or in the CNS. At the molecular level, blocking autocrine Wnt signaling did not affect HIFα-regulated OPC differentiation and myelination. We further identified HIFα–Sox9 regulatory axis as an underlying molecular mechanism in HIFα-regulated OPC differentiation. Our findings support a concept shift in our mechanistic understanding of HIFα-regulated CNS myelination from the previous Wnt-dependent view to a Wnt-independent one and unveil a previously unappreciated HIFα–Sox9 pathway in regulating OPC differentiation.SIGNIFICANCE STATEMENT Promoting disturbed developmental myelination is a promising option in treating diffuse white matter injury, previously called periventricular leukomalacia, a major form of brain injury affecting premature infants. In the developing CNS, hypoxia-inducible factor α (HIFα) is a key regulator that adapts neural cells to physiological and pathologic hypoxic cues. The role and mechanism of HIFα in oligodendroglial myelination, which is severely disturbed in preterm infants affected with diffuse white matter injury, is incompletely understood. Our findings presented here represent a concept shift in our mechanistic understanding of HIFα-regulated developmental myelination and suggest the potential of intervening with an oligodendroglial HIFα-mediated signaling pathway to mitigate disturbed myelination in premature white matter injury.  相似文献   
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