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"Congenital telangiectatic erythema" (Bloom's syndrome) is very rare; it is linked to a group of hereditary diseases and a common feature is cellular hypersensitivity to a variety of physical or chemical agents. The mode of transmission is autosomal-recessive. Characteristic criteria for Bloom syndrome are: consanguinity of the parents; androtropia; low birth weight, short stature (proportional); and persistent telangiectatic erythema in sun-exposed areas, sometimes with blistering. The syndrome is also associated with a facultative lack of antibodies. Of great importance is the high leukaemia morbidity among individuals with this syndrome; chromosomal aberrations and breakages play a significant role. Histological changes comprise an increase in dilated vessels in the upper dermis and damage and loss of elastic fibers. We give a review of Bloom's syndrome and present a case report.  相似文献   
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Two roads to rapid eye movement latency   总被引:3,自引:0,他引:3  
Although considerable attention has been paid to the accumulated body of data on sleep-related "markers" of affective illness, there has been ongoing controversy with respect to the application of these sleep measures. This report attempts to reexamine the data on the electroencephalographic sleep features of individuals with depressive illness from a different theoretical perspective. Our focus on rapid eye movement latency is intended to provide both a new interpretation of the available data and directions for future research.  相似文献   
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OBJECTIVE: Little is known about how patients who seek medical help for benign palpitations can be distinguished from those with clinically significant arrhythmias. This study tested whether patients with arrhythmia can be distinguished from those who are aware of sinus rhythm or extrasystoles on the basis of sex, prevalence of anxiety disorders, and heartbeat perception. METHODS: A consecutive sample of patients referred to a cardiology clinic participated in the study. Patients were diagnosed as having either arrhythmia (N = 62), extrasystoles (N = 75), or awareness of sinus rhythm (N = 47). They were assessed with use of the anxiety disorders and hypochondriasis modules of the Structured Clinical Interview for DSM-IV. Both patients and control subjects (N = 35) answered questionnaires measuring anxiety, fear of bodily sensations, and depression and underwent a heartbeat perception test. The present report focuses on patients who had palpitations but no comorbid cardiovascular disease. RESULTS: Patients with awareness of sinus rhythm could be distinguished from those with arrhythmia by several variables: female sex, higher prevalence of panic disorder, poor performance on the heartbeat perception test, report of palpitations when doing the test, higher heart rates, lower levels of physical activity, and (as trends) a greater prevalence of panic attacks, fear of bodily sensations, and depression. In contrast, patients with arrhythmias rarely reported palpitations when doing the test but were more likely to perceive their heartbeats accurately than patients with sinus rhythm and control subjects. Performance on the heartbeat perception test was intermediate in patients with extrasystoles; these patients also had an intermediate prevalence of panic disorder and intermediate depression scores. CONCLUSIONS: Measures of panic disorder and a simple heartbeat perception test could complement medical assessment in the diagnosis of patients who seek medical help for palpitations. The results also have implications for the treatment of patients with benign palpitations.  相似文献   
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Injured areas of the respiratory epithelium are subject to rapid repair by the migration of adjacent epithelial cells, a process termed "restitution". Rapid re-epithelialization is promoted by interactions between migrating cells and the extracellular matrix proteins. Furthermore, epidermal growth factor (EGF) as well as trefoil factor family (TFF) peptides are well known regulators of epithelial restitution due to their motogenic effects. Migration of the human bronchial epithelial cell line BEAS-2B in modified Boyden chambers was used as a model system for airway restitution. EGF or recombinant human TFF2 or TFF3 showed mainly chemotactic activity. The motogenic response was strictly dependent upon a haptotactic substrate, but to different degrees. EGF induced phosphorylation of extracellular signal-regulated kinases (ERK) 1/2, c-Jun-N-terminal kinase, p38, Akt, and p70S6K in BEAS-2B cells. Using specific inhibitors, the signaling cascades responsible for the motogenic response were shown to differ drastically when EGF was compared with TFF2. The motogenic effect of TFF2 was previously demonstrated to depend on ERK1/2 and protein kinase C activation; whereas the EGF-triggered motogenic response was completely independent of ERK1/2 activation but sensitive to the inhibition of phosphoinositide 3-kinase, p38, protein kinase C, or nuclear factor kappaB. However, the motogenic effects of EGF and TFF2 are additive. These data suggest that luminal EGF and TFF peptides can act synergistically in the human respiratory epithelium to enhance rapid repair processes in the course of diseases such as asthma.  相似文献   
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Myelin basic protein (MBP)-reactive T cells are thought to play an important role in the pathogenesis of multiple sclerosis (MS). In some patients with MS, these autoreactive T cells display a limited heterogeneity in their epitope recognition and T cell receptor (TCR) variable (V) gene usage. These individual-dependent properties of MBP-reactive T cells have led to the speculation that they may represent clonal expansion in vivo in some MS patients. In the present study, 51 MBP-reactive T cell clones derived from patients with MS and healthy individuals were examined for their epitope recognition and the TCR Vα and Vβ gene rearrangements. The V gene junctional region sequences of identified α and β genes were further analyzed to probe their clonal origins, as the sequences are unique for individual clones. Our data showed that 26 clones derived from nine patients with MS shared a predominant reactivity to the immunodominant regions of MBP, 84–102, 110–129 and 143–168, and used various TCR Vα and Vβ rearrangements. The V gene usage of the clones was restricted to certain Vα Vβ combination(s) in a given MS patient, but varied among different patients. The sequence analysis revealed that the clones generated from a given patient shared a limited or a single junctional region sequence pattern(s), indicating their oligoclonal or monoclonal origin(s). In contrast, 25 MBP-reactive T cell clones derived from normal individuals exhibited unfocused epitope recognition and V gene usage. Thus, the limited heterogeneity of MBP-reactive T cells in their structural and functional charactertistics reflects their clonal expansion in vivo in some patients with MS.  相似文献   
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