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91.
Granulomas and cholestatic--hepatocellular injury associated with phenylbutazone. Report of two cases 总被引:1,自引:0,他引:1
A combined cholestatic-hepatocellular injury and noncaseating granulomas occurred in two patients 1 and 4 weeks after phenylbutazone therapy. Both patients were jaundiced, one had a macular rash, and both had peripheral blood eosinophilia. Symptoms and signs subsided, and abnormal findings from tests of hepatic function rapidly returned to normal following withdrawal of the drug. Sections of liver biopsy specimens 6 months later showed no granulomas or other pathologic changes. Previously reported cases are reviewed. 相似文献
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93.
It is recognized that one infant death in a family indicates an increased risk of death of a subsequent sibling. This study examines which cause of death of a sibling is related to the mortality of the younger sibling and when. Longitudinal vital events data from the maternal and child health and family planning (MCH-FP) project and the comparison areas in Matlab, Bangladesh, were used. Primary causes of 868 neonatal deaths and 624 post-neonatal deaths resulting from 18,865 singleton live births in 1989-92 and those (967 as neonates and 708 as post-neonates) of their immediate elder siblings were categorised into infectious and non-infectious diseases. Multinomial logistic regression was used to estimate the risk of younger siblings dying in each age period from infectious and non-infectious diseases given the age and cause of deaths of older siblings and controlling for other biosocial correlates of infant mortality. A neonatal death of non-infectious causes in a family was twice as likely to be followed by another one occurring at the same age from similar causes compared with a surviving infant followed by a neonatal death from non-infectious causes. The MCH-FP project, though successful in reducing the risk of neonatal and post-neonatal mortality from infectious diseases, did not reduce the risk of dying from non-infectious diseases. 相似文献
94.
95.
This study investigated the mechanism of protein kinase C-mediated inhibition of ATP-induced phospholipase C activation in cultured bovine aorta endothelial cells (BAEC). In BAEC labeled with 3H-inositol, phorbol myristate acetate (PMA) prevented ATP-induced inositol bisphosphate and inositol trisphosphate formation. In membranes prepared from these PMA-treated cells, Ca(2+)-, sodium fluoride-, GTP gamma S-, and ATP plus GTP gamma S-stimulated inositol bisphosphate, but not inositol trisphosphate, formation was inhibited. Inositol trisphosphate phosphatase activity was not altered in membranes from PMA-treated BAEC. These results suggest that 1) protein kinase C inhibits ATP-induced phospholipase C activation in BAEC through interference with the coupling of phospholipase C with a G-protein and through an effect on phospholipase C itself, and 2) different mechanisms are responsible for the inhibition by protein kinase C of the phospholipase C-mediated hydrolysis of phosphatidylinositol bisphosphate and phosphatidyl-inositol phosphate. 相似文献
96.
97.
RG Stock K Chan M Terk JK Dewyngaert NN Stone P Dottino 《Canadian Metallurgical Quarterly》1997,37(4):819-825
The authors review the literature on intra-adenomatous pituitary apoplexy with special emphasis on pathophysiology, diagnosis and therapeutic approach. They present five cases, from a series of 86 patients with pituitary tumors, that developed this syndrome. The patients were diagnosed and followed by the Neurosurgery and Endocrinology Services of Hospital Universitario Clementino Fraga Filho, Universidade Federal do Rio de Janeiro. Diagnosis was confirmed by CT-Scan and MRI in all cases, and the treatment of choice was surgical. Conclusions point to the diagnostic difficulties and the urgency of treatment in this clinical setting. 相似文献
98.
The effects of Mg2+ concentration (Mg2+o, 0, 1.2, 2.4, and 4.8 mM) on the incidence of reperfusion arrhythmias and on the cellular electrical activity were studied in spontaneously beating rat hearts. The surface electrogram and the membrane potential were recorded in control conditions, during 10 min of regional ischemia (ligature of the left anterior descending coronary artery), and on reflow. Changes in Mg2+o did not alter action potential morphology but the depolarization induced by ischemia decreased with increasing Mg2+o. In hearts perfused with Mg2+ free solution or 1.2 mM subthreshold delayed afterdepolarizations (DADs) were often detected during ischemia. Moreover, DADs could be identified as initial events in the production of extrabeats or tachycardia appearing on reperfusion under these conditions. Chaotic electrical activity during fibrillation precluded the observation of DADs. The overall incidence (100%) and severity of ventricular tachyarrhythmias (80% tachycardia and fibrillation) was similar in both groups. At high Mg2+o, subthreshold DADs were occasionally observed during ischemia and often on reperfusion where they did not lead to the development of overt arrhythmias. Consequently, the incidence, severity, and duration of arrhythmic episodes on reflow was markedly reduced. Raising Mg2+ only on reperfusion did not prevent the development of arrhythmias, whose morphology in the intracellular recordings was similar to that found in hearts perfused without Mg2+ or with 1.2 mM. The recovery of sinus rhythm after 10 min of reperfusion was linearly related to Mg2+o. Our data strengthen the view that reperfusion arrhythmias belong to the Ca2+ mediated non reentrant type and suggest that Mg2+ counteracts these arrhythmias by depressing cytosolic Ca2+ oscillations. Besides, it appears that raising Mg2+o reduces ischemic K+o accumulation. The resulting changes in resting potential could contribute to lower DADs amplitude and thus decrease the arrhythmogenic potential of the Ca2+i oscillations induced by reperfusion. 相似文献
99.
100.
MA van der Kooij EM von der Mark JK Kruijt A van Velzen TJ van Berkel OH Morand 《Canadian Metallurgical Quarterly》1997,17(11):3107-3116
A protein that specifically binds oxidized LDL (Ox-LDL) has recently been characterized in mouse peritoneal macrophages and identified as macrosialin, a protein with a molecular weight of 95 kD. First, the present work shows that human monocyte-derived macrophages express a membrane protein with a molecular weight of approximately 120 kD that selectively binds Ox-LDL. Second, we tested whether this approximately 120-kD Ox-LDL binding protein had any relation to CD68, the human homologue of macrosialin. The following evidence was obtained to support the role of CD68 as an Ox-LDL binding protein: (1) Ligand blots with Ox-LDL and Western blots with Ki-M6, an anti-human CD68 monoclonal antibody, revealed a single band with a molecular weight of approximately 120 kD under reducing and nonreducing condition. (2) The expression patterns of the approximately 120-kD Ox-LDL binding membrane protein and of CD68 paralleled each other during monocyte/macrophage differentiation. (3) Digestion with N-glycosidase F demonstrated that both CD68 and the Ox-LDL binding protein are glycoproteins; both showed a similar shift of approximately 18 kD in apparent molecular weight. (4) CD68, probed with monoclonal antibody Ki-M6, and the approximately 120-kD Ox-LDL binding protein were coprecipitated with EMB11, another anti-CD68 antibody. About 5000 molecules of CD68 are expressed on the cell surface of human macrophages. Ligation of 125I-Ki-M6 to cells leads to its internalization and degradation. This capacity would be sufficient to allow for the specific uptake and degradation of Ox-LDL. Taken together, these data support a role for CD68 as a specific Ox-LDL binding protein in human monocyte-derived macrophages. 相似文献