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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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ObjectiveThis study was performed to assess the outcomes of Asian patients who underwent conversion from metal-on-metal total hip arthroplasty (MoM-THA) to cemented THA (CTHA).MethodsOne hundred and fifty-seven consecutive patients (157 hips) who underwent CTHA following primary MoM-THA from January 2005 to February 2015 were retrospectively analysed. The primary endpoints were the clinical outcomes. Follow-ups occurred at 3 months, 6 months, 1 year, 2 years, and then every 2 years following revision of MoM-THA.ResultsThe mean follow-up after conversion was 10 years (range, 5–14 years). Statistically significant improvements in the mean Harris hip score were observed between the preoperative and final follow-up evaluations (62.71 ± 13.85 vs. 84.03 ± 16.21, respectively). The major orthopaedic complication rate was 16.5% (26/157). Six (3.8%) patients underwent revision at a mean of 3.5 ± 1.3 years after conversion, predominantly because of prosthesis loosening or recurrent dislocation. Nine (5.7%) patients developed prosthesis loosening at a mean of 2.6 ± 1.1 years following conversion, two of whom requested revision surgery. Eleven (7.0%) patients developed prosthesis dislocation, four of whom requested revision surgery.ConclusionCTHA may yield favourable functional outcomes and a reduced rate of major orthopaedic complications.  相似文献   
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目的 研究活血解毒方对缺氧/复氧(H/R)所致的心肌细胞凋亡的影响。方法 体外培养H9C2心肌细胞并分成正常对照组(Control组)、缺氧复氧组(H/R组)、H/R + 活血解毒中药组、LY294002组和活血解毒中药 + LY294002组,其中正常对照组给予DMEM培养基培养,缺氧复氧组给予缺氧4 h、复氧6 h处理,缺氧复氧 + 活血解毒中药组、LY294002组和活血解毒中药 + LY294002组分别给予活血解毒中药、LY294002、活血解毒中药配合LY294002预处理24 h,然后均给予缺氧4 h、复氧6 h处理。采用CCK8检测各组心肌细胞的存活率,流式细胞术检测各组细胞凋亡水平,电镜观察各组心肌细胞中线粒体、自噬体的变化,Western Blot检测各组细胞凋亡蛋白半胱氨酸天冬氨酸蛋白酶3(Caspase3)、半胱氨酸天冬氨酸蛋白水解酶3(Cleaved caspase3)、β-连环蛋白(β-Catenin)、p-p65、B淋巴细胞瘤-2(B-cell lymphoma-2,Bcl-2)蛋白的表达。结果 活血解毒方预处理显著增加H/R诱导的H9C2心肌细胞凋亡,降低凋亡相关蛋白Cleaved caspase3、β-Catenin、p-p65表达,增加Bcl-2表达。结论 活血解毒方可通过抑制细胞凋亡,降低缺氧/复氧所致的心肌细胞损伤,其作用机制可能与PI3K信号通路相关。  相似文献   
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Recent experimental strategies to reduce graft-versus-host disease (GVHD) have focused largely on modifying innate immunity. Toll-like receptor (TLR)-driven myeloid differentiation primary response 88 (MyD88)-dependent signalling pathways that initiate adaptive immune function are also critical for the pathogenesis of GVHD. This study aimed to delineate the role of host MyD88 in the development of acute GVHD following fully major histocompatibility complex-mismatched allogeneic bone marrow transplantation (BMT). When myeloablated BALB/c MyD88 knock-out recipients were transplanted with C57BL/6 (B6) donor cells, they developed significantly more severe GVHD than wild-type (WT) BALB/c hosts. The increased morbidity and mortality in MyD88–/– mice correlated with increased serum levels of lipopolysaccharide and elevated inflammatory cytokines in GVHD target organs. Additionally, MyD88 deficiency in BMT recipients led to increased donor T cell expansion and more donor CD11c+ cell intestinal infiltration with apoptotic cells but reduced proliferation of intestinal epithelial cells compared with that in WT BMT recipients. Decreased expression of tight junction mRNA in epithelial cells of MyD88–/– mice suggested that MyD88 contributes to intestinal integrity. Cox-2 expression in the GVHD-targeted organs of WT mice is increased upon GVHD induction, but this enhanced expression was obviously inhibited by MyD88 deficiency. The present findings demonstrate an unexpected role for host MyD88 in preventing GVHD after allogeneic BMT.  相似文献   
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摘要:目的 分析色谱柱参数对盐酸四环素有关物质HPLC分析的影响,筛选影响关键杂质分离度以及理论塔板数的主要 柱参数。方法 针对《中国药典》2020版中盐酸四环素有关物质检查的色谱条件,使用多个品牌不同型号的色谱柱进行色谱分 析,使用SPSS软件进行模型回归,得到柱参数与目标因子分离度及理论塔板数的回归方程,并用实测值进行验证。结果 色谱 柱参数C是影响杂质4-差向四环素和土霉素分离度(R12)的重要参数,利用柱参数C可快速预测不同色谱柱的相似度,进而筛选 适宜四环素分析的色谱柱;探讨了金霉素理论塔板数(R5N)与柱参数之间的关系,其中参数B2对R5N影响较大。结论 建立柱参 数与色谱分析目标因子之间的联系,为盐酸四环素有关物质测定选择合适的色谱柱提供便利与指导。  相似文献   
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