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BackgroundThe effects of bronchial thermoplasty (BT) on smooth muscle (SM) and nerves in small airways are unclear.MethodsWe recruited 15 patients with severe refractory asthma, who received BT treatment. Endobronchial optical-coherence tomography (EB-OCT) was performed at baseline, 3 weeks' follow-up and 2 years' follow-up to evaluate the effect of BT on airway structure. In addition, we divided 12 healthy beagles into a sham group and a BT group, the latter receiving BT on large airways (inner diameter >3 mm) of the lower lobe. The dogs’ lung lobes were resected to evaluate histological and neuronal changes of the treated large airways and untreated small airways 12 weeks after BT.ResultsPatients receiving BT treatment had significant improvement in Asthma Control Questionnaire (ACQ) scores and significant reduction in asthma exacerbations. EB-OCT results demonstrated a notable increase in inner-airway area (Ai) and decrease in airway wall area percentage (Aw%) in both large (3rd-to 6th-generation) and small (7th-to 9th-generation) airways. Furthermore, the animal study showed a significant reduction in the amount of SM in BT-treated large airways but not in untreated small airways. Protein gene product 9.5 (PGP9.5)–positive nerves and muscarinic receptor 3 (M3 receptor) expression in large and small airways were both markedly decreased throughout the airway wall 12 weeks after BT treatment.ConclusionsBT significantly reduced nerves, but not SM, in small airways, which might shed light on the mechanism of lung denervation by BT.  相似文献   
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陈雅洁  吴节 《新中医》2020,52(5):124-126
结合中医理论及外界影响因素分析认为,排卵障碍性不孕以"肝气郁结、疏泄失调"为病机,治则立"疏肝解郁、调畅气机"为大法,探讨治疗该病选用肝俞施用龙虎交战针法的理论依据。为针灸治疗排卵障碍性不孕提供新的思路及方法,同时也体现了古典针法创新性的运用。  相似文献   
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Perivascular epithelioid cell tumor (PEComa) is a rare mesenchymal tumor originating from perivascular epitheloid cells showing melanocytic and smooth muscle differentiation. The uterus represents the second most common site of origin. A 49 years woman presented to our Hospital for a vaginal spontaneous expulsion of a mass suggestive for malignant mesenchymal tumor. The patient underwent total hysterectomy and bilateral salpingo-oophorectomy and the histopathological report was compliant with a PEComa with aggressive behavior. Medical Literature databases about PEComa were searched. The current literature identified near 90 cases of uterine PEComas and they are categorized as uncertain malignant potential or with aggressive behavior. Primary surgical excision represents the gold-standard treatment. Recently targeted therapy with mTOR inhibitors has been introduced with an important beneficial. In this paper we review the Literature about the uPEComa with aggressive behavior reporting the first case of spontaneous vaginal expulsion.  相似文献   
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Controlling cellular alignment is critical in engineering intestines with desired structure and function. Although previous studies have examined the directional alignment of cells on the surface (x–y plane) of parallel fibers, quantitative analysis of the cellular alignment inside implanted scaffolds with oriented fibers has not been reported. This study examined the cellular alignment in the x–z and y–z planes of scaffolds made with two layers of orthogonally oriented fibers. The cellular orientation inside implanted scaffolds was evaluated with immunofluorescence. Quantitative analysis of coherency between cell orientation and fiber direction confirmed that cells aligned along the fibers not only on the surface (x–y plane) but also inside the scaffolds (x–z & y–z planes). Our study demonstrated that two layers of orthogonally aligned scaffolds can generate the histological organization of cells similar to that of intestinal circular and longitudinal smooth muscle.  相似文献   
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PurposeThoracic aortic aneurysm (TAA) is a cardiovascular disease characterized by increased aortic diameter, treated with surgery and endovascular therapy in order to avoid aortic dissection or rupture. The mechanism of TAA formation has not been thoroughly studied and many factors have been proposed to drive its progression; however strong focus is attributed to modification of smooth muscle cells (SMCs). Latest research indicates, that microRNAs (miRNAs) may play a significant role in TAA development – these are multifunctional molecules consisting of 19–24 nucleotides involved in regulation of the gene expression level related to many biological processes, i.e. cardiovascular disease pathophysiology, immunity or inflammation.Materials and methodsPrimary SMCs were isolated from aortic scraps of TAA patients and age- and sex-matched healthy controls. Purity of isolated SMCs was determined by flow cytometry using specific markers: α-SMA, CALP, MHC and VIM. Real-time polymerase chain reaction (RT-PCR) was conducted for miRNA analysis.ResultsWe established an isolation protocol and investigated the miRNA expression level in SMCs isolated from aneurysmal and non-aneurysmal aortic samples. We identified that let-7 g (0.71-fold, p = 0.01), miR-130a (0.40-fold, p = 0.04), and miR-221 (0.49-fold, p = 0.05) significantly differed between TAA patients and healthy controls.ConclusionsFurther studies are required to improve our understanding of the pathophysiology underlying TAA, which may aid the development of novel, targeted therapies. The pivotal role of miRNAs in the cardiovascular system provides a new perspective on the pathophysiology of thoracic aortic aneurysms.  相似文献   
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杨雄  詹曙  谢栋栋 《磁共振成像》2016,7(10):775-779
目的研究前列腺磁共振图像中灰度不均匀现象(偏场)的校正方法。材料与方法从几组前列腺磁共振扫描数据中截取的横断面图像。将真实图像的分段常量特性与偏移场的平滑变化特性表达到图像模型中,构造一个能量函数,通过能量函数的最小化实现偏移场评估和组织分割。利用峰值检测技术自动获得能量函数的初始化参数,并用结合三角函数与多项式函数的一组基函数实现对偏移场的平滑拟合。结果定性的实验表明笔者的方法能对前列腺磁共振图像中的偏场现象进行有效的校正。另外通过与其他方法在变化系数、均方根、Jaccard相似度等指标下的定量对比发现,笔者的方法有更好的校正结果。结论结合峰值检测的偏移场校正方法能对前列腺磁共振图像中的灰度不均匀现象有效改善。  相似文献   
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