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31.
Oxidative metabolism of the human eosinophil   总被引:14,自引:1,他引:14  
We have compared the oxidative metabolism of human eosinophils (80%-90% purity) to that of neutrophils. Hexose monophosphate (HMP) shunt activity of eosinophils was higher than that of neutrophils under either resting or phagocytizing conditions. Eosinophil HMP shunt activity also was stimulated by phorbol myristate acetate, a membrane- active agent. Eosinophils showed a marked incorporation of 125I into trichloroacetic acid-insoluble material under resting conditions, which increased markedly during phagocytosis. Eosinophils likewise showed a greater reduction of nitroblue tetrazolium dye during phagocytosis than did neutrophils. Measurement of other parameters of oxidative metabolism indicated that eosinophils generated superoxide anion following phagocytosis and also elicited a burst of chemiluminescence similar to that observed during phagocytosis by neutrophils. Measurement of NADPH oxidase activity demonstrated that this enzyme was 3-6 times more active in fractions isolated from eosinophils than in corresponding fractions isolated from neutrophils; this was observed over a range of substrate concentrations. The eosinophil enzyme sedimented differently than the neutrophil enzyme with differential centrifugation; neither showed sedimentation characteristics of peroxidase. These data indicate that eosinophils possess a similar, although in some ways more potent, oxidative burst than neutrophils and are consistent with a role for NADPH oxidase in the initiation of that burst.  相似文献   
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Objective. To determine the features and outcomes of patients with giant cell arteritis (GCA) who have aneurysms or rupture of the thoracic aorta. Methods. Patients with GCA seen over a 40-year period who had aneurysms and/or rupture of the thoracic aorta were identified by assistance of a computerized indexing system. The presence of thoracic aortic aneurysms (TAA), with or without aortic valve insufficiency (AI), was determined by radiographs, computed tomography scans, and ultrasound studies of the thorax, angiograms of the aorta, and postmortem examination. Results. Ten men and 31 women with GCA were found to have TAA and/or rupture. Three developed TAA before GCA was diagnosed, 5 developed aortic findings near the time of the diagnosis, and 33 after the diagnosis of GCA (median of 7 years after diagnosis). Sixteen patients developed acute aortic dissection, which caused death in 8. Nineteen patients also had AI due to aortic root dilation, 15 of whom developed congestive heart failure. Eighteen patients underwent 21 surgical procedures for TAA resection and/or aortic valve replacement or repair. Aortitis was documented histologically in 10 cases. Conclusion. Thoracic aortic complications in GCA are associated with serious outcomes that have been underrecognized and may be fatal. Physicians should be alert to the development of these complications at any time in the course of GCA, even many years after usual symptoms have subsided.  相似文献   
34.
A 56-year-old male presented with a pruritic, generalized vesiculobullous eruption. His past history revealed classical symptoms of limited Hailey-Hailey disease for 34 years. Clinically, vesicles, bullae and occasional pustules were present and multiple biopsies confirmed this to be an unusual presentation of Hailey-Hailey disease. Various therapeutic modalities including topical and oral antibiotics, oral prednisone and dapsone failed to achieve sustained remission. Treatment with lowdose oral etretinate (25 mg daily) produced marked clinical improvement with complete suppression of new vesicle formation after 6 weeks.  相似文献   
35.
Dubin-Johnson综合征是一种先天性非溶血性黄疸,在临床中较罕见,需与其他原因所导致的黄疸相鉴别.本文报告了我院1例Dubin- Johnson综合征的诊治情况,有助于加深对该病的认识.  相似文献   
36.
自体骨髓干细胞移植治疗失代偿期肝硬化   总被引:12,自引:2,他引:12  
选择36例失代偿期肝硬化患者,年龄37~59岁,患者在无菌条件下,从髂后上棘抽取骨髓100~200mL,在体外分离纯化骨髓干细胞后,局部麻醉下经股动脉插管经肝动脉将分离的骨髓干细胞移植于肝脏。自移植后12周,25例(69.4%)患者谷丙转氨酶逐渐降低,由平均(2788.56±357.90)nkat/L降至(1077.05±440.25)nkat/L;22例(61.1%)患者总胆红素逐渐下降,由平均(151.47±25.77)μmol/L降至(69.93±18.86)μmol/L;27例(75%)患者白蛋白逐渐升高,由平均(25.17±11.79)g/L升至(30.87±12.17)g/L。在干细胞移植后凝血酶原活动度逐渐上升,由术前平均(25.89±12.67)%上升至术后12周的(50.39±19.38)%,患者凝血机制明显改善。移植后大多数患者身体状况有明显的改善;移植后12周腹水减轻的19例(52.7%),食欲改善的28例(77.7%),体力好转20例(58.3%),腹胀减轻17例(47.2%),36例干细胞移植患者未出现严重并发症。  相似文献   
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Nilsson  H; Torndal  UB; Eriksson  LC 《Carcinogenesis》1997,18(12):2447-2451
The metabolism of inositol 1,4,5-trisphosphate and inositol 1,3,4,5- tetrakisphosphate in homogenates and sub-fractions from normal rat liver and premalignant liver nodules was investigated. The activities of 5-phosphatase, expressed as pmol converted substrate per minute and mg protein, were equal when using the two substrates, and did not differ between normal and nodular homogenates. Subcellular fractions were purified by sequential steps of differential centrifugation and density gradient fractionation procedures. The total phosphatase activity was found to be distributed between cytosol (15%) and membraneous fractions (75%), with most of the enzyme activity residing in the plasma membranes. A doubling of phosphatase specific activity was seen in the nodular low density membrane fraction, containing Golgi apparatus and endosomes, as compared with normal liver. Inositol 1,4,5- trisphosphate 3-kinase activity was found to be exclusively cytosolic. No difference in this enzyme was seen between the two tissue types studied. Vasopressin (0.2 or 2 microM) had no effect either on phosphatase or kinase activity. The compartmentalization of inositol polyphosphate 5-phosphatase activity presents a possible explanation of earlier findings that premalignant liver tissue was able to respond with inositol 1,4,5-trisphosphate, but not inositol 1,3,4,5- tetrakisphosphate formation after agonist stimulation.   相似文献   
40.
A postal survey of recently appointed consultant paediatricians was undertaken to determine whether they perceived their training had adequately equipped them for their current job. The response rate was 69% (207/299). After excluding replies from consultants trained outside the UK the analysis was carried out on 167 replies. Trainees held a mean 5.2 posts during general and higher professional training, necessitating a mean 1.8 house moves. Altogether 82% felt moves were beneficial to training but 46% found moves 'very disruptive' to family life. Only 12% of district general hospital and 22% of teaching hospital senior registrars took two research sessions a week. Supervision and training in research was absent or poor for more than 60%; 24% felt major changes and 55% moderate changes were needed to current training. Training in non-clinical skills was particularly in demand and a curriculum for both trainers and trainees with regular appraisals is required. Research at senior registrar level needs review and educational methods improved to achieve better training in a shorter period.  相似文献   
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