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891.
J. LEAKE S. J. KELLIE† J. PRITCHARD† J. M. CHESSELLS† R. A. RISDON 《Histopathology》1989,14(3):255-268
A review of the pathological material from 42 children with non-Hodgkin's lymphoma seen over a 44 month period revealed 10 large cell tumours. Of these, six were classified as peripheral T-cell lymphoma, an entity rarely reported in childhood. Three patients were boys and three girls (median age 9.5 years), and extranodal presentation was a feature of two patients. Five had high-grade tumours; of these, three were classified as large cell anaplastic, Ki-1 positive and two as pleomorphic large cell. The remaining patient had a low-grade tumour of angioimmunoblastic type. T-cell subsets were examined in three cases and showed the following phenotypes: CD4-, CD8-; CD4+, CD8-; CD4-, CD8+. Three of the patients with high-grade tumours died, with a mean survival of 22 weeks. The remaining patients are alive and clinically disease-free for between 10 and 24 months after treatment. 相似文献
892.
V Karabela-Bouropoulou S Markaki D Prevedorou N Vidali 《Pathology, research and practice》1989,184(2):184-187
The histological similarities and the common localization are the main causes of difficulties concerning the differential diagnosis between giant cell tumor of bone and chondroblastoma. The purpose of the present study was to detect whether histochemistry and/or immunohistochemistry could help to make the distinction between these two entities easier. The study was based on cases of chondroblastoma and giant cell tumor of bone from patients in the 2nd and 3rd decades of life. Histochemical detection of special intracellular and extracellular components (glycogen, glycosaminoglycans) as well as immunohistochemical investigation using various tumor markers (S-100, NSE, a-1-ACT, lysozyme, fibronectin) were performed on parallel paraffin sections. The presence of abundant intracytoplasmic glycogen granules and the immunoreactivity of the cells of chondroblastoma with S-100 and NSE, together with the presence of acidic sulfated glycosaminoglycans in the stroma, could help the differential diagnosis of this tumor from giant cell tumor of bone. 相似文献
893.
Atrial natriuretic peptide (ANP) is a hormone release into the circulation by atrial cardiocytes (Gutkowska et al. 1984). Extracellular fluid volume expansion acts as a powerful stimulus for ANP secretion and results in the augmentation of its plasma concentration (Lang et al. 1985). Patients with active acromegaly demonstrate the increased extracellular fluid volume (Falkheden et al. 1964), while a successful treatment of the disease results in the disappearance of hypervolemia (Strauch et al. 1977). We have recently demonstrated that in patients with active acromegaly the increased total body plasma volumes are accompanied by the elevated plasma ANP concentrations, whereas, in the successfully treated patients, both: total plasma volumes and plasma ANP levels do not differ significantly from these in healthy subjects (Czekalski et al. 1988b). 相似文献
894.
895.
896.
Isolation and characterization of a distinct immunoregulatory isoform of alpha-fetoprotein produced by the normal fetus 总被引:1,自引:1,他引:0 下载免费PDF全文
In this report, we examine the functional significance of the molecular microheterogeneity of alpha-fetoprotein (AFP). In doing so, we have taken the direct approach of purifying the naturally occurring isomeric forms of fetal-derived AFP using a preparative anion exchange column linked to an automated fast protein liquid chromatography (FPLC) system followed by parallel testing of each isolated molecular variant for in vitro immunoregulatory activity. The data obtained demonstrate the presence of seven distinct variants of AFP as defined by their retention volumes on FPLC elution profiles, by their pIs on analytical IEF gels, and by Western blot analysis. Molecular mass determination by SDS-PAGE showed each isomer to be equivalent in size to 69,000-dalton native unfractionated AFP molecules. All the immunosuppressive activity of AFP was localized to a single variant representing only 6% of the total composition of native AFP. The immunoregulating isomer termed AFP-1 was the least acidic of the seven isolated variants with a pI of 5.1 and displayed a sialic acid content of 1 mol/mol of protein. The inhibitory activity of AFP-1 could be readily measured on T cell-dependent antibody synthesis, Con A-induced stimulation of Lyt-1+23- thymocyte DNA synthesis, and lymphokine-activated NK cell activity. All other isomers were without effect in these test systems. The immunosuppressive AFP-1 isomer also displayed the strongest growth-promoting influence on cultured bone marrow lymphocytes. There was no correlation between functional activity and degree of expression of sialic acid residues on the AFP molecules. These findings demonstrate that the immunoregulating function of AFP is confined to a distinct and relatively small subpopulation of native AFP molecules and should therefore contribute to the resolution of outstanding questions regarding the structure/function relationship of this onco-fetal glycoprotein. 相似文献
897.
S Ia Maramaa 《Terapevticheski? arkhiv》1989,61(9):128-130
The methodology of a so-called task force approach to the diagnosis is suggested. It determines the strategy of the physician's diagnostic searches in some problems occurring in the examination of patients afflicted with the given disease. The problems (stages, levels of examination) show how one should reason, i. e. they form concrete bases for clinical thinking. According to this methodology, the symptoms should be classified with separate diagnostic problems--trends or stages of the patient's examination at the stage of a probable diagnosis establishment. The task force approach is a method of analysis which prevents potential gross diagnostic errors by means of deciding the main questions (functional, pathogenetic, etc.). A well-defined wording of the above-indicated problems--concrete regularities of the clinical thinking--are of paramount importance in teaching therapy. Examples are provided of the task force approach to the diagnosis of pyelonephritis, infectious myocarditis, anemia, and some other diseases. 相似文献
898.
899.
M S Lipsky 《American family physician》1986,34(5):173-177
Patients with chronic hiccups should be carefully examined for an underlying disorder while receiving symptomatic treatment. Treatment includes physical maneuvers, drugs such as chlorpromazine, metoclopramide, anticonvulsants or quinidine, and other, less tested modalities such as hypnosis. Only those patients with disabling hiccups that do not respond to conservative treatment should be considered for phrenic nerve surgery. 相似文献
900.
A lawsuit directed by parents at a day care program following an outbreak of infectious disease would most likely be based on the legal theory of negligence--the failure to exercise due care as required by circumstances. In the determination of liability for infectious diseases in child day care, the element of causation is most critical. Did the day care facility's actions or failure to act cause the harm? Another important question is whether an infectious disease can be occupational and under what circumstances. Although worker's compensation laws initially had no provisions for occupational disease, now all states recognize responsibility for them. Awareness of potential problems with legal liability and establishment of procedures to minimize risk are important for day care providers, public health officials, clinicians, and parents. 相似文献