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Eight antibodies (UCHL1 (CD45RO), MT1 (CD43), MT2 (CD45R), 4KB5 (CD45R), MB1 (CD45R), MB2, L26 (CD20) and LN1 (CDw75)) have been examined for reactivity with routine specimens of normal and hyperplastic lymphoid organs (n = 6), non-Hodgkin's lymphomas (n = 62), Hodgkin's disease (n = 27) and non-lymphoid malignancies (n = 9). In normal and hyperplastic lymphoid organs, UCHL1 and MT1 stained predominantly T cells; 4KB5, MB1, MB2, L26 and LN1 stained predominantly B cells; and MT2 reacted with a subset of B and T cells. The lineage of the neoplastic cells was correctly identified in 24 of 28 (86%) peripheral T-cell lymphomas; and in 31 of 35 (88%) B-cell malignancies. In two cases of lymphocyte-predominant Hodgkin's disease, the Hodgkin's and Reed-Sternberg (H&RS) cells were 4KB5+, L26+ and/or LN1+. The H&Rs cells in nodular sclerosis and mixed cellularity Hodgkin's disease were positive with 4KB5 in 17 of 25 cases. Antibodies UCHL1, MT1, MB1, MB2, L26 and LN1 also labelled some H&RS cells, but in a much smaller proportion of the cases. In three of nine non-lymphoid neoplasms, UCHL1 and MB2 showed a staining of the neoplastic cells, but the staining was cytoplasmic rather than membrane-associated. The remaining antibodies were unreactive with the non-lymphoid malignancies. It is concluded that many non-Hodgkin's lymphomas can be typed in routine specimens, and that antibodies UCHL1, MT1, L26 and LN1 are especially useful in this respect. The antibodies do not provide a means of distinguishing between non-Hodgkin's lymphomas and Hodgkin's disease.  相似文献   
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In the awake brain, the global metabolic rate of oxygen consumption is largely constant, while variations exist between regions dependent on the ongoing activity. This suggests that control mechanisms related to activity, that is, neuronal signaling, may redistribute metabolism in favor of active networks. This study examined the influence of gamma-aminobutyric acid (GABA) tone on local increases in cerebellar metabolic rate of oxygen (CeMR(O(2))) evoked by stimulation of the excitatory, glutamatergic climbing fiber-Purkinje cell synapse in rat cerebellum. In this network, the postsynaptic depolarization produced by synaptic excitation is preserved despite variations in GABAergic tone. Climbing fiber stimulation induced frequency-dependent increases in synaptic activity and CeMR(O(2)) under control conditions. Topical application of the GABA(A) receptor agonist muscimol blocked the increase in CeMR(O(2)) evoked by synaptic excitation concomitant with attenuation of cerebellar blood flow (CeBF) responses. The effect was reversed by the GABA(A) receptor antagonist bicuculline, which also reversed the effect of muscimol on synaptic activity and CeBF. Climbing fiber stimulation during bicuculline application alone produced a delayed undershoot in CeBF concomitant with a prolonged rise in CeMR(O(2)). The findings are consistent with the hypothesis that activity-dependent rises in CeBF and CeMR(O(2)) are controlled by a common feed-forward pathway and provide evidence for modification of cerebral blood flow and CMR(O(2)) by GABA.  相似文献   
75.
Kim  D; Porter  DH; Siegel  JB; Simon  M 《Radiology》1989,172(3):721-723
Various complications have been reported after insertion of the Greenfield filter. This report describes an unusual complication after suprarenal placement of this filter: spreading of the filter struts, with perforation of the inferior vena cava, and penetration of the aorta and a vertebral body, followed by fracture of one of the struts.  相似文献   
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The present study was undertaken to evaluate whether the persistent hypoperfusion following cortical spreading depression (CSD) in rat brain was accompanied by alterations of regional cortical glucose consumption (rCGU). rCGU was measured using 2-deoxy-[14C]glucose and autoradiography at 15–60 min after single CSD episodes. rCGU did not differ in cortical regions invaded by CSD as compared to the contralateral side and to sham-treated rats. The results suggested impairment of the metabolism-flow couple after CSD.  相似文献   
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Three pregnancies (two I. parae and one II. para) with abnormally low urinary estrogen excretion of less than 5 mg estrogens per day have been investigated in this study. After intravenous injection of 100 mg DHA-S to the mothers no increase of estrogen production was observed. The level of human placental lactogen, was found within normal range. Ultrasonographic measurement of fetal size and monitoring of the fetal heart rate have demonstrated fetal benefit. At the end of pregnancy the cervix of both did not dilate after infusion of Syntocinon. Healthy male infants were delivered by Caesarean sections in both cases. The II. para, however, developed spontaneous labour and delivery at term. Clinical and laboratory tests have indicated the possibility of rare placental sulphatase deficiency. After delivery the placental steroid sulphatase activity was measured as the rate of hydrolysis of (6,7-3H) oestrone-sulphate or (4-14C) dehydroepiandrosterone-sulphate during in vitro incubation with the homogenate or the microsomal fraction from the pathological placentae. In all three cases the specific activity of 3-sulphatase was considerably (more than 80%) decreased when compared to three normal placentas, whereas the activity of the other enzymes (17beta-hydroxysteroidoxidoreductase, delta4/5-isomerase, aromatizing enzyme system) was found within the normal range.  相似文献   
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