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Manuelle Medizin - Anhand der Beobachtung einer Manifestation des Proatlas mit Ausbildung eines zusätzlichen zervikalen Segments bei einem 8‑jährigen Jungen wird das Krankheitsbild... 相似文献
63.
Interleukin-4 (IL-4) is a potent mediator of growth and differentiation of cells of several hematopoietic lineages. Interleukin-5 (IL-5) is a lineage-specific hematopoietic growth factor that stimulates the production of eosinophils and eosinophil colonies from normal human bone marrow cells. By using somatic cell hybrids and in situ chromosomal hybridization, we localized the IL-4 and IL-5 genes to human chromosome 5 at bands q23-31, a chromosomal region that is frequently deleted [del(5q)] in patients with myeloid disorders. By in situ hybridization, the IL-4 and IL-5 genes were found to be deleted in the 5q- chromosome of four patients with refractory anemia (RA) or therapy-related acute nonlymphocytic leukemia (t-ANLL), who had a del(5q). Thus a small segment of chromosome 5 contains IL-4, IL-5, IL- 3, and GM-CSF as well as other genes such as CD14 and EGR1. Our findings that each of these genes was deleted in the 5q- chromosome suggest that loss of function of one or more of these genes may play an important role in the pathogenesis of hematologic disorders associated with a del(5q). 相似文献
64.
High-density activation mapping of fractionated electrograms in the atria of patients with paroxysmal atrial fibrillation 总被引:5,自引:0,他引:5
Thomas Rostock MD Martin Rotter MD Prashanthan Sanders MBBS PhD Yoshihide Takahashi MD Pierre Jaïs MD Mlze Hocini MD Li-Fern Hsu MBBS Frderic Sacher MD Jacques Clmenty MD Michel Haïssaguerre MD 《Heart rhythm》2006,3(1):27-34
BACKGROUND: Areas of complex fractionated atrial electrograms (CFAEs) have been implicated in the atrial substrate of atrial fibrillation (AF). The mechanisms underlying CFAE in humans are not well investigated. OBJECTIVES: The purpose of this study was to investigate the regional activation pattern associated with CFAE using a high-density contact mapping catheter. METHODS: Twenty patients with paroxysmal AF were mapped using a high-density multielectrode catheter. CFAE were mapped at 10 different sites (left atrium [LA]: inferior, posterior, roof, septum, anterior, lateral; right atrium [RA]: anterior, lateral, posterior, septum). Local atrial fibrillation cycle length (AFCL) was measured immediately before and after the occurrence of CFAE, and the longest electrogram duration (CFAEmax) was assessed. RESULTS: Longer electrogram durations were recorded in the LA compared with the RA (CFAEmax 118 +/- 21 ms vs 104 +/- 23 ms, P = .001). AFCL significantly shortened before the occurrence of CFAEmax compared with baseline (LA: 174 +/- 32 ms vs 186 +/- 32 ms, P = .0001; RA: 177 +/- 31 ms vs 188 +/- 31 ms, P = .0001) and returned to baseline afterwards. AFCL shortened by >or=10 ms in 91% of mapped sites. Two different local activation patterns were associated with occurrence of CFAEmax: a nearly simultaneous activation in all spines in 84% indicating passive activation, and a nonsimultaneous activation sequence suggesting local complex activation or reentry. CONCLUSION: Fractionated atrial electrograms during AF demonstrate dynamic changes that are dependent on regional AFCL. Shortening of AFCL precedes the development of CFAE; thus, cycle length is a major determinant of fractionation during AF. High-density mapping in AF may help to differentiate passive activation of CFAE from CFAE associated with an active component of the AF process. 相似文献
65.
Dvorak AM; Tepper RI; Weller PF; Morgan ES; Estrella P; Monahan-Earley RA; Galli SJ 《Blood》1994,83(12):3600-3612
We used light and electron microscopy to analyze the eyelid inflammation that develops in transgenic mice that overexpress interleukin-4 (IL-4; Tepper et al, Cell 62:457, 1990). Analysis of alkaline Giemsa-stained plastic sections examined by light microscopy (Dvorak et al, J Exp Med 132:558, 1970), as well as by routine transmission electron microscopy, indicated that the mast cells in the inflammatory eyelid lesions were undergoing piecemeal degranulation, a form of secretion in which the cells' cytoplasmic granules exhibit characteristic morphologic changes that are thought to be associated with the prolonged, vesicle-mediated release of the granules' constituents. Moreover, by using a newly reported enzyme affinity-gold method, which stains histamine based on binding to diamine oxidase-gold (Dvorak et al, J Histochem Cytochem 41:787, 1993), we show that these activated mast cells had released much of their histamine content. The eyelid lesions also exhibited increased numbers of mast cells; interstitial fibrosis, particularly around cutaneous nerves and blood vessels; activated fibroblasts; focal axonal damage; venules with endothelial cells containing numerous vesiculo-vacuolar organelles; and infiltrates of neutrophils and eosinophils. Our findings illustrate that overexpression of the IL-4 gene in vivo can result in eyelid lesions associated with piecemeal degranulation of mast cells, as well as tissue fibrosis and a variety of other pathologic changes. These results also represent the first direct morphologic evidence for histamine secretion by mast cells in vivo. 相似文献
66.
Helen Skouteris Briony Hill Marita McCabe Boyd Swinburn Paul Sacher Paul Chadwick 《Early child development and care》2014,184(5):649-657
The aim of this paper was to compare the recruitment strategies of two recent studies that focused on the parental influences on childhood obesity during the preschool years. The first study was a randomised controlled trial (RCT) of the Mind, Exercise, Nutrition?…?Do It! 2–4 obesity prevention programme and the second was a longitudinal cohort study. For both studies, the desired population were families with preschool children at risk of developing overweight or obesity. Hence, families from diverse ethnic and socio-economic backgrounds were sought. Funding for the RCT provided the resources to adopt a targeted approach to recruitment whereas for the longitudinal study, recruitment was random and opportunistic, rather than specific and targeted. The RCT reported higher child body mass index-for-age z scores, more families not from an Australian or New Zealand background, and more families in the lowest income bracket, suggesting that strategically targeted approaches to recruitment are more likely to achieve the desired sample. 相似文献
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Han S. Lim Mélèze Hocini Remi Dubois Arnaud Denis Nicolas Derval Stephan Zellerhoff Seigo Yamashita Benjamin Berte Saagar Mahida Yuki Komatsu Matthew Daly Laurence Jesel Carole Pomier Valentin Meillet Sana Amraoui Ashok J. Shah Hubert Cochet Frédéric Sacher Michel Haïssaguerre 《Journal of the American College of Cardiology》2017,69(10):1257-1269