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This study presents a unique observational approach to basketball, based on the theory of psychological performance crisis in competition. The approach used takes into account the responses of a player's actions to significant social factors such as team-mates, spectators, the coach and the referees. The contribution of this approach beyond traditional observational techniques is discussed. In our investigation, a single case design was used, in which a professional basketball player was observed during 10 home and 3 away games of the regular season. The relations between the observations and the crisis concept are discussed in detail. In addition, some relevant methodological and applied aspects are presented.  相似文献   
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Several “progeroid” syndromes have now been identified. The De Barsy syndrome is an autosomal recessive syndrome of dwarfism, mental deficiency, an “aged” appearance at birth, abnormal elastic fibers on skin biopsy, and lax skin, large helices, eye abnormalities, lax joints, hypotonia, and athetoid posturing. We report one case and review 11 cases from the literature. To understand the abnormal appearance of the elastic fibers on biopsy, we performed elastin gene expression studies on fibroblasts cultured from our patient's skin. Molecular hybridization studies revealed reduced elastin mRNA steady-state levels as compared with age matched control individuals. Assuming normal rates of mRNA translation, reduced elastin synthesis would occur. Diminished dermal elastin content could explain the altered cutaneous elasticity, decreased elastic fibers in the skin, and many clinical manifestations of individuals with this condition.  相似文献   
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This study comprises an analysis of the data on 332 persons totally buried by avalanches in Switzerland between 1981 and 1989. The survival rate was calculated with the aid of a computer-assisted estimation procedure according to Turnbull. The curve pattern was interpreted according to pathophysiological considerations, on the basis of which the time course of the battle for survival was divided into 4 phases: 1) Survival phase: until 15 minutes after burial under the snow masses. The survival probability amounts to 93% and is, thus, higher than so far assumed. Almost all those buried survived this period of the time provided they were not fatally injured and received first aid. 2) Asphyxia phase: duration of burial under the avalanche from 15 to 45 minutes. The probability of survival sank dramatically during this period from 93% to about 25% (fatal kink of the survival probability curve). Those buried under the snow without an air pocket die of acute asphyxia (the point of no return) and the mortality rate reaches its maximum in this phase. 3) Latent phase: the period as from 45 minutes following the avalanche until the time of rescue. This phase is survived only in the presence of an air pocket. With sufficient oxygen reserves and freedom of thoracic movement a "phase of relative safety" occurs, whereby the survival probability diminishes further only slowly. The first deaths due to hypothermia arise after 90 minutes. 4) Rescue phase: from the time of extrication from the snow until arrival in hospital. There is an increased risk of a fatal outcome during the rescue procedure and immediately afterwards through augmented hypothermia.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Deletion of the gene encoding the Fc immunoglobulin G receptor IIB (FcgammaRIIB) results in a fulminant, lupus-like disease in C57BL/6 but not BALB/c mice. Here we have investigated this strain-specific, epistatic loss of tolerance using gene-targeted immunoglobulin variable heavy-chain (V(H)) alleles 3H9 or 56R, which encode DNA-specific heavy chains, expressed on the C57BL/6 or BALB/c background. The combination of C57BL/6 and V(H) 56R (B6.56R) resulted in a loss of tolerance; hybridoma and single-cell analysis indicated an FcgammaRIIB-independent difference in immunoglobulin light-chain usage, consistent with an alteration in receptor editing. FcgammaRIIB deficiency resulted in an increase in immunoglobulin G (IgG) antibodies to DNA in the serum, an increased frequency of anti-DNA-reactive IgG(+) B cells with a plasma cell phenotype and immune complex deposition in the glomeruli and renal disease in B6.56R mice. Thus, FcgammaRIIB provides a distal peripheral checkpoint to limit the accumulation of autoreactive plasma cells, thereby maintaining tolerance.  相似文献   
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Microscopic polyangiitis (microscopic polyarteritis)   总被引:8,自引:0,他引:8  
Microscopic polyangiitis ("microscopic polyarteritis") is a form of necrotizing small vessel vasculitis that most often affects venules, capillaries, arterioles, and small arteries, although it occasionally involves medium-sized arteries. Microscopic polyangiitis is a more appropriate name than microscopic polyarteritis because some patients have no evidence for arterial involvement. The absence or paucity of immunoglobulin localization in vessel walls distinguishes microscopic polyangiitis from immune complex mediated small vessel vasculitis, such as Henoch-Schonlein purpura and cryoglobulinemic vasculitis. Clinical, epidemiological, and pathologic differences warrant the separation of microscopic polyangiitis from polyarteritis nodosa on the basis of involvement of capillaries and venules by the former but not the latter. Pauci-immune necrotizing and crescentic glomerulonephritis, and hemorrhagic pulmonary capillaritis are common in patients with microscopic polyangiitis. Microscopic polyangiitis is the most common cause for pulmonary-renal vasculitic syndrome. The vasculitis in patients with microscopic polyangiitis is pathologically indistinguishable from the vasculitis of Wegener's granulomatosis and Churg-Strauss syndrome. Granulomatous inflammation distinguishes Wegener's granulomatosis from microscopic polyangiitis. Asthma and eosinophilia distinguish Churg-Strauss syndrome from microscopic polyangiitis. Microscopic polyangiitis, Wegener's granulomatosis, and Churg-Strauss syndrome are all associated with circulating antineutrophil cytoplasmic autoantibodies.  相似文献   
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Falk KI  Ernberg I 《Archives of virology》1999,144(11):2219-2227
Summary.  Epstein-Barr virus (EBV) episomal DNA is extensively methylated in Burkitt lymphoma derived cell lines. In this study we examined whether lytic viral cycle reactivation is dependent on demethylation of critical viral genes. Viral replication was induced in the Burkitt’s lymphoma cell line Daudi by the combination of 12-O-tetradecanoylphorbol-13-acetate (TPA) and sodium-butyrate. Two regions necessary for EBV replication, the BZLF1 immediate early region and the origin of lytic cycle replication (ori Lyt) were demethylated during the early phase of the lytic virus cycle. Demethylation was observed while production of new (unmethylated) viral DNA was blocked by phosphonoformic acid (PFA). This suggests that demethylation, which may be instrumental for the onset of the lytic cycle, is an active process independent of viral DNA repli- cation. Received February 13, 1999 Accepted June 30, 1999  相似文献   
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A report is given on an outbreak of enteritis which occurred in July 1982 in a kibbutz near Jerusalem. About 150 of the 512 inhabitants were affected.Campylobacter jejuni was isolated from ten out of 42 stool samples examined toward the end of the outbreak. No other enteric pathogen was found. Strong circumstantial evidence indicated an association between the outbreak and the use of water from an unprotected reservoir, but no bacteriological confirmation was obtained.  相似文献   
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