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21.
Multiple mechanisms can explain a tachycardia associated or not with a heart disease. It is important to establish its origin, particularly if advanced heart disease is present, for the treatment. Complete electrophysiological study remains an important means of diagnosis. We report the case of a 39-year old man, who had a dilated cardiomyopathy since the age of 25 years and who complained of tachycardia. These symptoms were shown to be related to atrioventricular nodal re-entrant tachycardia at electrophysiological study and a specific treatment was indicated.  相似文献   
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Common variable immunodeficiency (CVID) is characterized by low levels of immune globulins and lack of antibody. Mutations in transmembrane activator and calcium-modulating cyclophilin ligand (TACI), are found in 8-10%, associated with autoimmunity and splenomegaly. Some patients with mutations had increased serum levels of TACI. Because of this, and the prevalence of autoimmunity, splenomegaly, and lymphadenopathy, we quantitated levels of TACI ligands, a proliferation inducing ligand (APRIL) and B cell activating factor (BAFF) and TACI in serum of 77 patients. CVID subjects had markedly increased serum levels of BAFF (p<0.0001), APRIL (p<0.0001), and TACI (p=0.001) but there was no relationship between levels and autoimmunity, lymphadenopathy, splenomegaly, B cell numbers, or mutations in TACI. Peripheral blood mononuclear cells of CVID subjects had increased levels of BAFF mRNA. We conclude that increased constitutive production and/or underlying immuno-regulatory or inflammatory conditions lead to enhanced release of ligands; however, the biological result remains unclear.  相似文献   
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BACKGROUND: Levels of IgE antibody to egg white of greater than 7 kIU/L are highly predictive of clinical reactivity to egg, and lower levels often require evaluation with oral food challenge (OFC) to establish definitive diagnosis. OFCs have inherent risks, and diagnostic criteria indicating high likelihood of passing would be clinically useful. OBJECTIVE: We sought to determine whether the size of the skin prick test (SPT) to egg white adds diagnostic utility for children with low egg white-specific IgE antibody levels. METHODS: A retrospective analysis of clinical history, egg white-specific IgE antibody levels, SPT responses, and egg OFC outcomes was performed. RESULTS: Children who passed (n = 29) egg OFCs and those who failed (n = 45) did not differ significantly in age, clinical characteristics, or egg white-specific IgE levels. There were, however, significant differences between both egg white SPT wheal response size and egg/histamine SPT wheal index. Children who failed egg OFCs had a median wheal of 5.0 mm; those who passed had a median wheal of 3.0 mm (P = .003). Children who failed egg OFCs had a median egg/histamine index of 1.00; those who passed had a median index of 0.71 (P = .001). For egg white-specific IgE levels of less than 2.5 kIU/L, an SPT wheal of 3 mm or an egg/histamine index of 0.65 was associated with a 50% chance of passing. CONCLUSION: In children with low egg white-specific IgE levels, those with smaller SPT wheal responses to egg were more likely to pass an egg OFC than those with larger wheal responses. The size of the egg white SPT response might provide additional information to determine the timing of egg OFC. CLINICAL IMPLICATIONS: The size of the egg white SPT wheal response might provide the clinician with additional information to determine the timing of egg OFC in children with low egg white-specific IgE antibody levels.  相似文献   
25.
An important measure of brain health is the integrity of white matter connectivity structures that link brain regions. Studies have found an association between poorer sleep quality and decreased white matter integrity. Stress is among the strongest predictors of sleep quality. This study aimed to evaluate the association between sleep quality and white matter and to test if the relationship persisted after accounting for stress. White matter microstructures were measured by diffusion tensor imaging in a population of Old Order Amish/Mennonite (N = 240). Sleep quality was determined by the Pittsburgh Sleep Quality Index. Current stress levels were measured by the perceived stress scale. Exposure to lifetime stress was measured by the lifetime stressor inventory. Microstructures of four white matter tracts: left and right anterior limbs of internal capsule, left anterior corona radiata, and genu of corpus callosum were significantly correlated with sleep quality (all p ≤ 0.001). The current stress level was a significant predictor of sleep quality (p ≤ 0.001) while lifetime stress was not. PSQI remained significantly associated with white matter integrity in these frontal tracts (all p < 0.01) after accounting for current stress and lifetime stress, while current and lifetime stress were not significant predictors of white matter in any of the four models. Sleep quality did not have any substantial mediation role between stress and white matter integrity. Sleep quality was significantly associated with several frontal white matter tracts that connect brain structures important for sleep regulation regardless of current or past stress levels.  相似文献   
26.
A butyric acid pro-drug, pivaloyioxymethyl butyrate, AN-9, developed in our laboratory, was previously shown to act as a differentiation-inducing and an anti-cancer agent. In this study we have shown that both AN-9 and butyric acid caused a transient hyperacetylation of histones, which returned to basal levels after 6 and 12 hr, respectively. This activity precedes the induction of differentiation elicited by both agents. AN-9 induced acetylation of histones at a concentration one order of magnitude lower than butyric acid. Pre-treatment of the cells with esterase(s) inhibitors diminished the ability of AN-9 to inhibit proliferation and induce differentiation. The above suggests that the intracellular release of butyric acid fragment, from the pro-drug, is catalyzed by cellular esterase(s).  相似文献   
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BACKGROUND: We report the short-term outcome of our patients participating within the Eurotransplant age-matching program, where kidneys from donors >65 years are transplanted to recipients >65 years regardless of human leukocyte antigen (HLA) compatibility but with short cold ischemia times, in comparison with patients >60 years transplanted with HLA-matching. METHODS: Twenty-five patients (66.7+/-2.6 years) (donors 69+/-4.3 years) participated in this program (group A). The control group consisted of 21 patients (63+/-2.6 years) (group B) (donors 47.6+/-17.3 years). RESULTS: Despite significant differences in donor age, cold ischemia time (12.3+/-4.6 hr in A, 22.8+/-4.8 hr in B, P<0.001) and a mean of 4.4+/-1.4 vs. 2.3+/-1.6 HLA-mismatches (P<0.001), there was no difference regarding the incidence of delayed graft function (64 vs. 57%), rejections (52 vs. 66.7%), infections (56 vs. 52.4%), and other complications (80 vs. 71.4%). Mean serum creatinine after 6 months was 1.94+/-0.49 and 1.83+/-0.67 mg/dl (NS). CONCLUSION: The short-term results of the age-matching program are promising and comparable with results from patients of similar age with HLA-matching.  相似文献   
29.
Evaluating an activity intervention with hemodialysis patients in Israel   总被引:2,自引:0,他引:2  
As a life-threatening and potentially disabling disease, End Stage Renal Disease and its treatment cause stress as well as other psychosocial problems for patients and their families. This paper examines the results of an innovative activity-based intervention aimed at reducing some of the psychosocial repercussions of hemodialysis. A modified withdrawal/reversal design was employed to compare patients participating in the intervention and those who did not, at two points in time. The findings confirmed that dialysis patients in general have relatively high levels of psychological distress, difficulty adhering to the treatment regimen and poor self-rated health. Patients participating in the group activity were more anxious and had lower levels of interdialytic weight gain than the non-participants. After the intervention was terminated, levels of psychological distress, hostility and phobic anxiety among patients in the treatment group dropped, while their weight gain continued to be less than that of non-participating patients. The implications of these findings as well as the methodological difficulties entailed in this type of study are examined.  相似文献   
30.
Carcinoid tumours are enigmatic, slow growing malignancies, which occur most frequently (74%) in the gastrointestinal tract. Symptoms of the carcinoid syndrome (flushing and diarrhoea) are infrequent, occurring in approximately 10% of the patients with small bowel carcinoid. A 45-year-old patient with multiple liver metastases, diagnosed in 1994 with nonHodgkin's lymphoma after undergoing surgery for a distal ileal tumour, was referred to us by the Department of Haematology. At that moment the issue of a differential diagnosis with a carcinoid tumour arose, due to the long evolution and lack of evidence to support the initial diagnosis. The carcinoid syndrome was in fact present (the patient experiencing flush after small amounts of alcohol and emotions) and also we identified elevated values of 5HIAA. Reevaluation of the histologic sections of the ileal tumour as well as an ultrasound guided fine needle aspiration of an intrahepatic lesion confirmed the diagnosis of "carcinoid tumour". This conclusion lead to new therapeutic options for this patient. One of the main therapeutic options used in treating multiple liver metastases from a carcinoid tumour is chemoembolization and this case offered an excellent opportunity to present this therapy.  相似文献   
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