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A structured discourse strategy, employing child echoic imitations and adult expansion, was used to teach 5 autistic children two-term semantic relations. The 5 male preschoolers in late Stage I of linguistic development were exposed systematically to two-term semantic relations in a structured dialogue with a clinician. A combined multiple baseline and AB(A) design was used to examine the relationship between the clinician expansions and the children's subsequent spontaneous imitations and spontaneous productions. The results showed that an increase in modeling and expansion was related to an increase in the children's initial spontaneous imitations of two-term relations. Further, following the increase in spontaneous imitations, spontaneous productions of the two-term relations increased and were maintained, whereas spontaneous imitations subsequently decreased.  相似文献   
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Summary Allotransplantation of solid organs transfers passenger leucocytes which may give rise to a state of persistent microchimaerism. In this report we describe the case of a patient who developed a solitary plasmacytoma in a transplanted kidney more than 10 years after allografting. The diagnosis was established on the basis of the presence of a monoclonal IgG kappa peak in the serum, and light chain proteinuria, the plasmacytoid features of tumour cells including cell surface expression of IgG, kappa light chains, CD20, CD38 and CD56, the absence of lytic bone lesions and a normal bone marrow biopsy, and the disappearance of the monoclonal IgG peak after graft nephrectomy. A donor origin of the tumour was established by HLA DNA typing of tumour, tumour-free kidney tissue, and peripheral blood leucocytes, respectively.  相似文献   
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BACKGROUND: Blue dyes used for lymphatic mapping in sentinel lymph node biopsy cause intraoperative anaphylactic reactions in up to 2.7% of patients. With increasing implementation of this technique, the incidence of anaphylaxis to these dyes can be expected to increase. In the literature, the chemically often unrelated and inconsistently designated dyes have been confused, adding to other inconsistencies in the nomenclature. OBJECTIVE: To demonstrate the nomenclature, chemical and physiologic differences, and allergenicity of the various blue dyes used in a medical context. METHODS: We describe a patient with an intraoperative grade IV anaphylactic reaction to isosulfan blue. Immediate-type hypersensitivity was proved by positive skin test reactions and CD63 expression to isosulfan blue and cross-reactivity to patent blue V. RESULTS: A review of the literature clarified the exact nomenclature of the blue dyes and the possible pitfalls of confusing nomenclature in the context of structurally closely related dyes with different allergenic properties. For the detection of type I hypersensitivity, intracutaneous tests are valuable tools. An IgE-mediated mechanism has been shown recently. In most cases, sensitization exists without known previous exposure in a medical context. This may be due to the widespread use of such dyes in objects of everyday life. Preoperative antiallergic medication use does not prevent anaphylactic reactions but apparently reduces their severity. CONCLUSION: For better comparison and precision, the Chemical Abstracts Service number of the respective dye should always be given.  相似文献   
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BACKGROUND: We have seen several patients with itchy lichenified plaques located bilaterally on the elbows and/or knees and have named this condition 'psoriatic neurodermatitis' (PN). OBJECTIVE: The purpose of this study was to compare clinical and histopathological characteristics of these patients to those of patients with typical lichen simplex chronicus (LSC). METHODS: Nineteen patients with PN and 34 patients with typical LSC were included. Besides clinical dermatological evaluation, the prick test was carried out on 49 patients; the Phadiatop test on 40 patients; the patch test with European standard series on 47 patients; histopathological evaluation on 39 patients; and clinical psychiatric examination on 38 patients. RESULTS: Almost exclusively, PN was seen in females and was located on the extremities. It caused more plaques than typical LSC did. In PN, the plaques were smaller, sharper, more keratotic and less excoriated, and had fewer lichenoid papules around them. Itching was usually more severe in the evening, while resting and in a hot environment in typical LSC, but not in PN. In plaques of PN, microabscesses in the horny layer, hypogranulosis, regular acanthosis and thinning of the suprapapillary plates were more frequent, and hyperpigmentation in the basal layer was less. In patients with PN, depressive disorder was found more frequently; and generalized anxiety disorder or psychosomatic characteristics, less. There were no significant differences in the results of prick, Phadiatop and patch tests between patients with PN and those with typical LSC. CONCLUSION: In our opinion, it is most likely that the so-called PN is itchy psoriasis superimposed by LSC.  相似文献   
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Ten thrombocytopenic patients (platelets < 10–24 × 10(9)/L) who were refractory to platelet transfusion were investigated for their responsiveness to staphylococcal protein A column therapy. Nine patients had previously been treated with steroids, intravenous immune globulin, and/or other forms of immunosuppressive therapy without improvement in their transfusion response. All patients were receiving multiple platelet transfusions without achieving 1-hour corrected count increments (CCIs) > or = 7500. Eight patients had antibodies that reacted with platelets and were directed against HLA class I antigens, ABO antigens, and/or platelet-specific alloantigens. Plasma (500-2000 mL) from each patient was passed over a protein A silica gel column and then returned to the patient. Patients received from 1 to 14 treatments. A positive response to protein A therapy was defined as at least a doubling of the pretreatment platelet count and/or two successive 10- to 120-minute posttransfusion CCIs > or = 7500. Following plasma treatments, 6 of 10 patients responded with daily platelet counts that averaged 48 +/− 11 × 10(9) per L as compared with counts of 16 +/− 7 × 10(9) per L (p < 0.0005) before treatment. Posttransfusion CCI values determined in four of these patients averaged 2480 +/− 810 and 10,010 +/− 3540 (p < 0.005) before and after treatment, respectively. In contrast, among the four unresponsive patients, platelet counts averaged 10 +/− 9 and 13 +/− 10 × 10(9) per L (p = NS), respectively, while posttransfusion CCIs were 700 +/− 1410 and 1520 +/− 2460 (p = NS), respectively.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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The effect of acute administration of nicotine on the secretory function of the human parotid gland was investigated in 4 male volunteers. After intravenous infusion of 20 micrograms nicotine/kg b.w. within 10 min in all subjects an increased salivary amylase activity and protein concentration was observed. This phenomenon is believed to be caused by a stimulation of parotid beta-adrenoceptors secondary to a nicotine-induced release of catecholamines from the adrenals.  相似文献   
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