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81.
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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AIM: To determine whether fetal intrauterine resuscitation using tocolysis and delayed delivery is better for the fetus than emergency delivery when fetal hypoxia is suspected because of a non-reassuring fetal heart-rate (FHR) pattern using conventional heart rate monitoring. METHODS: This was a prospective and randomized study, conducted between 2001 and 2004 at Pereira Rossell Hospital, Montevideo, Uruguay. The population consisted of 390 fetuses, in which intrauterine distress was diagnosed using electronic FHR monitoring. Of these, 197 were randomly assigned to the emergency delivery group and 193 to the fetal intrauterine resuscitation group. The inclusion criteria were: term singleton pregnancy, in labor, cephalic presentation, and no placental accidents. RESULTS: The time between randomization and birth was 16.9 +/- 7.6 min (mean +/- SD) for the emergency delivery group, and 34.5 +/- 11.7 min (mean +/- SD) for the resuscitation group. The relative risk (RR) of acidosis in the umbilical artery (pH < 7.1) in the emergency delivery group was 1.47 (0.95-2.27). The RR of base deficit < or =12 mEq/L in the emergency delivery group was higher than in the resuscitation group (RR = 1.48 [1.0-2.2], P = 0.04). When considering the need for admission to the neonatal care unit, the relative risk was higher in the emergency delivery group than in the resuscitation group (RR = 2.14 [1.23.3.74], P = 0.005). No maternal adverse effects were reported. CONCLUSION: Tocolysis and delayed delivery renders better immediate neonatal results than emergency delivery when fetal distress is suspected because of a non-reassuring fetal heart pattern. In addition, it may decrease the need for emergency delivery without increasing maternal and fetal adverse side-effects.  相似文献   
86.
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   
87.
Mitochondrial ATP synthase has been recently detected at the surface of different cell types, where it is a high affinity receptor for apoA-I, the major protein component in high density lipoproteins (HDL). Cell surface ATP synthase (namely ecto-F1-ATPase) expression is related to different biological effects, such as regulation of HDL uptake by hepatocytes, endothelial cell proliferation or antitumor activity of Vγ9/Vδ2 T lymphocytes. This paper reviews the recently discovered functions and regulations of ...  相似文献   
88.
Long permanent remissions in malignant hematopoietic disorders can often be achieved by autologous bone marrow transplantation (ABMT) or by allogenic bone marrow transplantation (BMT). Previous studies have shown that such therapies may induce osteoporosis due to iatrogenic ovarian failure. The administration of hormone replacement therapy (HRT) in these women could prevent the adverse effects of long-term ovarian failure without remarkable side effects. The aim of this study was to evaluate how the bone mass is affected by HRT in patients undergoing ABMT or BMT adjusting the results for age, weight, and height. Subjects and methods: Thirteen women with previous ABMT/BMT were treated with a standard dose (0.625 mg/day) of conjugated equine estrogen (CEE) or with 50 μg/day of 17-β-estradiol in transdermal therapeutic systems (TTS) plus 5 mg/day of medroxyprogesterone acetate sequentially added to the last 12 days of estrogen therapy. Bone mass was measured prior to and 12 months following HRT. Blood samples were collected before therapy and during the 6th and 12th treatment months. Results: The mean time elapsed between bone transplantation and HRT initiation was 13.0 months (range 3–26 months). Before treatment nine patients were osteopenic and after HRT bone mass increased in all cases. Following ABMT/BMT, hepatic hyperenzymemia was detected in three patients. After 6 and 12 months of treatment no significant changes were observed in hepatic enzymes. Conclusion: Although hepatic hyperenzymemia is commonly considered as a contraindication for HRT, our results suggest that HRT is safe for these patients and that such therapy should be initiated after transplantation in women to prevent adverse effects of long-term ovarian failure.  相似文献   
89.
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   
90.
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   
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