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81.
Accessory pathways are typically located along the left or right atrioventricular junction. Distinct ventricular pre-excitation patterns determined by surface electrocardiography can provide reasonable pathway localization prior to invasive mapping and catheter ablation. We report an accessory pathway producing an unusual electrocardiographic appearance suggestive of ventricular outflow region pre-excitation. Pacing maneuvers and standard intracardiac recordings confirmed an atrial insertion immediately adjacent to the atrioventricular (AV) node and supported a ventricular insertion at the outflow tract region well away from the AV junction. The elimination of pathway conduction was achieved with radiofrequency (RF) energy at the atrial insertion after successful ice mapping excluded AV block at the target site. This is the second such pathway observed at our institution over a 20-year period.  相似文献   
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The Wnt signaling pathway has recently been demonstrated to play an important role in regulation of bone formation. LRP5 is thought to signal through the canonical Wnt pathway. In humans, LRP5 loss-of-function mutations lead to low bone mass with fractures, while LRP5 gain-of-function mutations lead to high bone mass, thus identifying LRP5 as an important regulator of bone mass. Patients with sclerosteosis have a severe skeletal disorder with progressive bone overgrowth due to a loss of function of the SOST gene, which implicates its role as a suppressor of bone formation. Recent study revealed that SOST is a BMP antagonist with unique ligand specificity, negatively regulating bone formation by repressing BMP-induced osteoblast differentiation or function or both.  相似文献   
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To stimulate granulopoiesis, we gave recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF; 120 microgram/m2/d) to a patient with congenital neutropenia. The treatment resulted in marked increases in white blood cell counts (maximum, 17,400/microL), consisting mainly of eosinophils (maximum, 13,050/microL) and monocytes (maximum, 1305/microL), rather than neutrophils (maximum, 798/microL). Circulating phagocytes (97% eosinophils) derived after GM-CSF treatment were less effective in chemotaxis, slower but equally effective in phagocytosis, and more effective in H2O2 production compared with normal control neutrophils, but comparable in chemotaxis and H2O2 production to control eosinophils. Before GM-CSF treatment, the bone marrow showed a maturation defect in the neutrophilic series that persisted after treatment despite marked increases in mature cells of other lineages. In vitro agar culture of bone marrow cells before GM-CSF treatment showed a normal number of granulocyte colonies; however, maturation was limited to the metamyelocyte stage. Although the absolute number and cycling rates of myeloid colony forming cells (predominantly eosinophils) increased after treatment, the maturation defect in the neutrophilic series persisted. The finding that GM-CSF induced stimulation of proliferation, which was coupled with maturation in the eosinophilic and monocytic but not the neutrophilic components, suggests that this patient had an intrinsic cellular or humoral defect in neutrophil maturation.  相似文献   
84.
Oxidative challenge can compromise intestinal growth and death responses. This study examines the effect of chronic consumption of subtoxic levels of peroxidized lipids on intestinal redox balance and turnover and the effect of glutathione (GSH) supplementation. Male Sprague-Dawley rats were fed standard rat chow or 4% peroxidized menhaden oil chow (2–8 weeks). Intestinal GSH and glutathione disulfide (GSSG), GSH synthetic and redox enzymes as well as proliferative (ornithine decarboxylase, ODC) and apoptotic activities were evaluated. Chronic peroxide intake did not affect overall animal growth, but decreased intestinal GSH/GSSG ratio that directly correlated with decreased GSH and increased GSSG, and suppressed peak circadian ODC activities and postprandial mucosal apoptosis. Supplementation with GSH restored the mucosal GSH/GSSG ratio and abrogated the peroxide-induced suppression of intestinal cell turnover. Collectively, the results show that chronic lipid peroxide consumption induces intestinal GSH redox imbalance that interferes with regulation of enterocyte death and proliferation in vivo. These disruptive effects of lipid peroxides were reversed by GSH supplementation in accordance with the normalization of tissue GSH/GSSG redox balance.  相似文献   
85.
Severe cold agglutinin disease with hemodynamic compromise requires rapid stabilization of the autoimmune hemolytic anemia as a bridge to the immunosuppressive effect of rituximab. Herein, we describe eculizumab treatment of severe complement‐mediated hemolysis in a patient whose hemodynamic status deteriorated in spite of supportive blood transfusions and therapeutic plasma exchange.  相似文献   
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Objective. To characterize postgraduation placement plans of 2013 doctor of pharmacy (PharmD) graduates.Methods. A cross-sectional survey of PharmD graduates from 8 midwestern colleges of pharmacy was designed to capture a comprehensive picture of graduating students’ experiences and outcomes of their job search.Results. At graduation, 81% of 2013 respondents had postgraduate plans, with approximately 40% accepting jobs and 40% accepting residencies or fellowships. Eighty-four percent of graduates reported being pleased with offers received, and 86% received placement in their preferred practice setting. Students perceived that securing residencies was more difficult than securing jobs. Students who participated in key activities had a nearly sevenfold increase in successful residency placement.Conclusion. While the demand for pharmacists decreased in recent years, responses indicated successful placement by the majority of 2013 graduates at the time of graduation.  相似文献   
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