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We previously showed cell–cell contacts of human dermal fibroblasts to induce expression of the hepatocyte growth factor/scatter factor (HGF) in a process designated as nemosis. Now we report on nemosis initiation in bone marrow mesenchymal stem cells (BMSCs). Because BMSCs are being used increasingly in cell transplantation therapy we aimed to demonstrate a functional effect and benefit of BMSC nemosis for wound healing. Nemotic and monolayer cells were used to stimulate HaCaT keratinocyte migration in a scratch-wound healing assay. Both indicators of nemosis, HGF production and cyclooxygenase-2 expression, were induced in BMSC spheroids. When compared with a similar amount of cells as monolayer, nemotic cells induced keratinocyte in vitro scratch-wound healing in a concentration-dependent manner. The HGF receptor, c-Met, was rapidly phosphorylated in the nemosis-stimulated keratinocytes. Nemosis-induced in vitro scratch-wound healing was inhibited by an HGF-neutralizing antibody as well as the small molecule c-Met inhibitor, SU11274. HGF-induced in vitro scratch-wound healing was inhibited by PI3K inhibitors, wortmannin and LY294002, while LY303511, an inactive structural analogue of LY294002, had no effect. Inhibitors of the mitogen-activated protein kinases MEK/ERK1/2 (PD98059 and U0126), and p38 (SB203580) attenuated HGF-induced keratinocyte in vitro scratch-wound healing. We conclude that nemosis of BMSCs can induce keratinocyte in vitro scratch-wound healing, and that in this effect signaling via HGF/c-Met is involved.  相似文献   
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0 引言 胃镜检查是上消化道疾病诊断的重要方法之一 .了解重复胃镜检查的原因及结果 ,有利于探讨疾病发生发展的基本规律 ,有利于发现诊断和治疗中存在的问题 ,从而提高对消化疾病的诊治水平 .1 材料和方法1.1 材料 随机抽检 1996 / 1998胃镜检查资料为调查对象7812例 ,其中行 2次以上胃镜检查者 937例 .调查内容包括性别、年龄、职业、主要症状和体征、病程、初步诊断、内镜检查时间、次数、内镜诊断、病理诊断、确诊时间 .1.2 方法 回顾性调查上述材料的临床特征 .列表统计研究对象一般情况的分布状况 ,计算各年龄段比例构成 ,各病…  相似文献   
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Pulmonary arterial hypertension is a progressive disorder that may result in right heart failure and death. Atrial level shunts in the presence of pulmonary hypertension may allow right‐to‐left mixing with maintenance of cardiac output and improved survival. However, excessive mixing at the atrial level can cause undue systemic desaturation, increased fatigue and decreased exercise tolerance even in the presence of adequate cardiac output. A 5½‐year‐old was diagnosed with pulmonary hypertension, a large atrial septal defect and right‐to‐left shunting. Medical therapy over an 18‐month period was successful in decreasing pulmonary artery pressure and pulmonary vascular resistance. However, because of the size and position of the intracardiac defect, symptoms of fatigue, and severe systemic desaturation with only minor activities persisted. Fenestrated surgical closure of the defect was thus undertaken to decrease the degree of atrial mixing, but still allow atrial decompression if necessary. Subsequent hemodynamic evaluation has demonstrated continued improvement, and all previous symptoms have resolved. Repeated echocardiography has confirmed patency of the atrial fenestration with left‐to‐right atrial flow.  相似文献   
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Healing of an arthrodesis occurs optimally when the prepared joint surfaces are held rigidly under compression [1]. We routinely use the “Chisel test” intra-operatively to determine whether we have achieved adequate compression and rigidity after fixation of our foot and ankle fusions. This previously un-reported technique uses tools already on hand when performing an arthrodesis and takes seconds to perform.  相似文献   
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The aim of this study was to determine the efficacy of long-term oral β -carotene supplementation for correcting impaired β -carotene status in cystic fibrosis patients. Thirty-five patients (2.3-30.5 years of age) with coefficients of fat absorption of 46-96% (median 88%) received β -carotene 0.5 mg/kg daily and were followed over a 16-month treatment period. Baseline plasma β -carotene concentrations in patients (meanSD, 0.090.06 μ mol/1) were significantly lower than those of age-matched controls (0.860.56 μ mol/1) ( p < 0.0001). Concentrations increased rapidly and reached a plateau at or before 3 weeks that was maintained throughout the study period. Values obtained at 3 weeks (0.890.64 μ mol/1) were significantly higher ( p < 0.0001) than those at baseline and did not differ from controls. Plasma retinol and α -tocopherol concentrations increased during the observation period, but remained within normal ranges. Plasma retinyl palmitate, which was below the detection limit in all but one patient at baseline, did not increase. Thus oral β -carotene supplementation is effective and normalizes β -carotene status of cystic fibrosis patients without evidence of significant side effects. β -Carotene, cystic fibrosis, LDL-cholesterol, oral supplementation, retinol, α-tocopherol  相似文献   
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