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41.
Large granular lymphocytic (LGL) leukaemia and chronic natural killer cell lymphocytosis (CNKL) are chronic indolent disorders often associated with neutropenia and constitutional symptoms. Severe anaemia occurs in about 20% of patients and is currently treated with corticosteroids followed by oral cyclophosphamide in non-responders. 30% of patients fail initial measures, and salvage therapy is inadequate. We describe three transfusion-dependent patients (two with T-LGL leukaemia, one with CNKL) refractory to corticosteroids, cyclophosphamide, and in one case fludarabine. Cyclosporine A (CSA) initiation resulted in prompt transfusion-independence and was well tolerated in all patients, making it an attractive alternative therapy for this disorder. 相似文献
42.
J. Randolph Swartz Ira M. Lesser Kyle B. Boone Bruce L. Miller Ismael Mena 《International journal of geriatric psychiatry》1995,10(6):437-446
Global and regional cerebral blood flow (CBF) were evaluated with single photon emission computerized tomography (SPECT) utilizing both 133Xenon (133Xe) (47 subjects, 47–82 years old) and 99Tc-hexamethylpropyleneamine oxime (99Tc-HMPAO) (27 subjects, 47–80 years old). The 133Xe results showed: among total subjects, no age-related decline in global CBF, but a significant regional decline in the occipital lobe (p < 0.05); among men, significant age-related declines in global, frontal, temporal, occipital and right hemisphere CBF (all p < 0.05); among women, no age-related decline in global or regional CBF. The 99Tc-HMPAO results showed no age-related decline in either global or regional perfusion among total subjects, men or women. These results suggest that age-related global and regional (including frontal lobe) CBF declines do not occur in healthy control subjects after the age of 45 years. However, gender differences in age-related CBF changes warrant further study. 相似文献
43.
Stijnen Annemiek M. Hovinga Suzanne Langemeijer Mariska W. E. Hoogerkamp Arendien van Bezooijen Cornells F. A. Danhof Meindert 《Pharmaceutical research》1993,10(7):1046-1051
The aim of the present investigations was to study the influence of increasing age on the pharmacodynamics of valproate in BN/BiRij rats, applying a threshold for electrically induced localized seizure activity as a measure of the anticonvulsant effect. Seven groups of healthy male BN/BiRij rats were used, aged 3, 6, 12, 19, 25, 31, and 37 months. Individual plasma concentration versus anticonvulsant effect relationships were determined during a continuous intravenous infusion of sodium valproate at a rate of 5.5 mg/min/kg. The infusion was terminated when the anticonvulsant effect intensity had reached the maximum attainable level or at a total infusion time of three hours. A nonlinear relationship between valproate concentration and anticonvulsant effect intensity was observed with no maximal effect in the concentration range up to 1200 mg · L–1. With increasing age a parallel shift in the concentration versus anticonvulsant effect relationships toward lower concentrations occurred. Thus increasing age appears to be associated with an increased sensitivity to the anticonvulsant effect of valproate.Suzanne Hovinga: Deceased January 30, 1991. 相似文献
44.
Adolf Pfefferbaum Edith V. Sullivan Margaret J. Rosenbloom Paula K. Shear Daniel H. Mathalon Kelvin O. Lim 《Psychiatry Research: Neuroimaging》1993,50(4):257-274
This cross-sectional study used a semi-automated analysis technique to quantify regional brain cerebrospinal fluid (CSF) volumes derived from computed tomography (CT) in 84 healthy men ranging from 21 to 82 years of age and 28 patients meeting Research Diagnostic Criteria for alcohol dependence. The goals were to replicate an earlier CT study of an independent sample of alcoholic and control subjects (Pfefferbaum et al., 1988a; Zipursky et al., 1988) and to compare CT assessments of brain changes with magnetic resonance imaging (MRI) assessments made in the same alcoholic patients (Pfefferbaum et al., 1992). Regional brain changes associated with normal aging were derived by regression analysis, using CT data collected from the healthy control subjects. As in the earlier CT study and in the concurrent MRI study, ventricular and sulcal CSF volumes in alcoholic patients were greater than would be expected for their age. Furthermore, the present CT study replicated the previous CT and MRI findings of a positive relationship between age and CSF volume enlargement in alcoholic patients over and above the normal age-related increase in CSF volume, suggesting greater vulnerability of the aging brain to alcohol. Comparison of CT-and MRI-derived estimates of ventricular and cortical sulcal volume revealed high correlations (>0.80). MRI and CT produced similar absolute ventricular volumes, while MRI produced larger sulcal volume estimates than did CT. The difference in sulcal volume estimate may be due to differences between CT and MRI in slice thickness and sensitivity to partial volume effects. 相似文献
45.
L H Anderson T L McDonald G M Thiele L W Klassen 《Journal of clinical laboratory analysis》1992,6(3):113-118
Different assay systems have been used to quantitate lymphokine-induced natural cytotoxic activity as a measure of immune status. This study compares the effects of inducing cytotoxicity in a bulk culture system, where effector cells are transferred to a micro culture well for assay, to a micro culture system where the effector cells are not transferred. The effector/target ratio for both the bulk and micro culture systems was calculated using the number of viable effector cells present at the time of target cell addition. After overnight incubation with interleukin-2 (IL-2), the lytic activity of murine spleen cells to targets using a micro culture system was increased two-fold over the bulk culture method. This increase was amplified further after 5 days of activation with IL-2, in that the micro culture system resulted in a four-fold increase in cytotoxic activity. The loss of some adherent cells in the bulk culture system did not explain the overall decrease in recovered cytotoxicity. The difference appeared to be related to cell loss during centrifugation. Therefore, the E/T ratios are different in the two systems if not corrected for the number of viable cells. 相似文献
46.
Atsuo Furuhashi M.D. Yasutaka Akasaki M.D. Masayasu Sato M.D. Koho Miyoshi M.D. 《Psychiatry and clinical neurosciences》1994,48(3):645-653
Abstract: The behavioral effects of ceroid-lipofuscin accumulation, induced by intraperitoneal administration of acetyl-ethyl-tetramethyl-tetralin (AETT) in Wistar rats for 3 months, were examined in the present studies. A significant increase in neuronal ceroid-lipofuscin was demonstrated neuropathologically as well as morphometrically. Although the AETT-intoxicated rats showed neither alteration of locomotor activity nor shock sensitivity, a significant impairment of learning ability, especially an acquisition trial in passive avoidance tests, was observed. Results of the present studies indicate the possibility that a diffuse lipofuscin accumulation causes a learning impairment in rats. The results also imply the possibility of a significant role of age-related lipofuscin accumulation in the dementing processes of human especially in the elderly. 相似文献
47.
We have studied 21 babies with IgE-mediated food allergy (FA) sensitized via breast milk. The diagnosis of IgE-mediated FA was based on the response to elimination diet and challenge tests, and was confirmed by positive RAST and skin tests. The children exhibited immediate symptoms, such as urticaria, angioedema, and asthma. Only 5/21 children developed tolerance to the offending food at the median age of 14 years. The children who failed to develop tolerance still have high levels of IgE antibodies towards the offending food. In conclusion, the results of our long-term follow-up study show that the natural history of FA in children sensitized via breast milk may be less optimistic than generally reported. 相似文献
48.
49.
魔芋精粉对大鼠脑、肝、心血管细胞老化的影响 总被引:10,自引:0,他引:10
本文用含1%魔芋精粉的饲料喂饲大鼠18个月,观察魔芋精粉对大鼠细胞老化的影响。结果表明,长期食用魔芋精粉可延缓脑神经胶质细胞、心肌细胞和大、中动脉内膜内皮细胞的老化进程,预防动脉粥样硬化,改善心、脑和血管的功能。 相似文献
50.
J. M. Greally L. Y. Boone S. G. Lenkey S. L. Wenger M. W. Steele 《American journal of medical genetics. Part A》1992,44(3):334-339
A child with manifestations of acrogeria and metageria, two “premature aging” syndromes, is presented. Because of his indistinct phenotype and because the question has been previously raised as to whether these conditions are separate, we propose the designation of acrometageria to describe this phenotypic continuum. As there is much in common clinically between acrometageria and the syndrome of type III procollagen deficiency (Ehlers-Danlos type IV), it might be presumed that a similar pathogenesis for acrometageria exists. This possibility has been tested previously, without demonstrating specific quantitative or qualitative deficits, but with some indirect evidence that collagen metabolism is deranged in these patients. One such crude indicator is the elevation of urinary hyaluronic acid levels, demonstrated in our patient and also observed in the phenotypically distinct Werner and Hutchinson-Gilford premature aging syndromes. On one hand, it could be argued that this supports the concept that premature aging syndromes exist as a biological continuum. On the other hand, it is equally valid to argue that syndromes of premature aging are so described merely because they include recognizable changes of normal aging and that the demonstration of an underlying mutation in a collagen gene, for example, invalidates their study as models of accelerated normal aging. © Wiley-Liss, Inc. 相似文献