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31.
Neutrophil oxidative metabolism, C3d and beta 2 microglobulin levels, were assessed in nine consecutive patients undergoing cardiopulmonary bypass surgery with polypropylene hollow fiber oxygenators for open cardiac operations. Generation of oxygen free radicals by neutrophils was measured as luminol-enhanced chemiluminescence after stimulation with opsonized Zymosan and phorbol myristate acetate. A significant increase in light emission was detected by using both of the chemiluminescence stimulators. Moreover, a remarkable and significant increase in C3d levels was found already at 10 min. Conversely minimal changes in levels of beta 2 microglobulin were detected during cardiopulmonary bypass surgery. These data suggest that the impact of the patient blood with the foreign surface of cardiopulmonary bypass results in activation of phagocyte cells with increased potential in oxygen consumption. These effects could be partially complement-mediated.  相似文献   
32.
A sample of 400 Lebanese-born women who gave birth at Auburn District Hospital in 1987-1988 was compared with a sample of 400 Australian-born women who gave birth in the same time period. The Lebanese-born women were found to be older and of higher parity than were their Australian-born counterparts; and to have booked their hospital admission significantly later in pregnancy than did the Australian-born women. Lebanese-born women also had frequently made a consanguineous marriage. Certain antenatal and intrapartum complications were more common in the Lebanese-born women, and perinatal mortality and morbidity rates were higher among their infants. The particular problems of pregnancy in Lebanese-born women, and possible ways of overcoming these, are discussed.  相似文献   
33.
Diazepam binding inhibitor (DBI) is a neuropeptide of 11 kDa molecular size and is unevenly distributed in human and rat brain. It appears to function as a negative allosteric modulator of GABAA receptors. In the present paper, using antibodies directed against several synthetic peptides, which correspond to selective regions of human DBI (DBI 51-70, DBI 37-50, DBI 81-101), it is shown that DBI is processed into at least 6 peptide fragments in both postmortem human brain and in cerebrospinal fluid (CSF). One of these fragments was identified as the synthetic DBI 51-70 fragment (an eikosaneuropeptide, ENP) by combined chromatographic procedures. Immunoblotting analysis of the other fragments, by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (PAGE), revealed an apparent molecular size, ranging from 3-4 kDa for four of them and a larger molecular form of 8 kDa. On the basis of the immunological properties, a tentative amino acid sequence was deduced.  相似文献   
34.
35.
OBJECTIVE: Compare the immunological and echocardiographic data of decellularized versus cryopreserved allografts used for RVOT reconstruction during Ross operation. METHODS: From 16/01/03 thru 07/10/03, 20 Ross operations were performed using decellularized (n=11) or cryopreserved (n=9) allografts. Echocardiography was done at discharge, 1, 3, 6 and 12 months and annually thereafter. Samples for determination of antibodies against HLA class I and II were obtained preoperatively and at days 5, 10, 30, 90 and 180 postoperatively. These samples were tested by the ELISA method in LAT-M dishes (unspecific) for identification of circulating antibodies and the results expressed as mean sample values (Is=DO/cutoff). If positive, LAT-E (specific) was performed and PRA levels determined. RESULTS: There was no mortality. Cryopreserved allografts showed marked Is values elevations for class I and II antibodies which started at the first month and remained elevated up to 6 months. In contrast, of the patients receiving decellularized allografts, seven remained negative, two patients had only marginal elevation of class I antibodies and two patients showed abnormal elevations of PRA levels. This response happened earlier than in the cryopreserved group, starting on the 5th postoperative day and has returned to baseline levels in one case. Echocardiography showed mild, but significant, elevation of gradients in cryopreserved valves but none in the decellularized. CONCLUSIONS: Decellularized allografts had normal function up to 18 months and showed important reduction of the immunogenic response when compared to cryopreserved valves.  相似文献   
36.
Asthma patients that depend on emergency department (ED) services are generally considered to have extremely poor disease control and prognosis. It is important to identify characteristics related to poor disease control and frequent visits to the ED to apply appropriate clinical management. This study comprised a cross-sectional survey of consecutive patients with asthma exacerbation (age ≥12 years) presenting at the adult ED of a large, tertiary care, university-affiliated hospital over a 2-month period. The frequent visitors (FV) were defined by ≥3 visits to the ED in the preceding year, and the occasional visitors (OV) by ≤2 visits. Eighty-six patients (61 females and 25 males) were included in the study (mean age 38 ± 18 years). Of these patients, 51.2% were FV and 48.8% were OV. Sixty-nine percent had annual income lower than A$3000 and 66.3% had ≤8 years of the formal education. Only 18.6% had used inhaled corticosteroids, 79.1% identified the asthma attack severity, 70.9% increased or initiated inhaled β-agonist, 20.9% increased or initiated steroid therapy, and 55.8% had an asthma action plan for attack. The number of hospital admissions in past year (OR 4.3, P = .02), use of home nebulizer (OR 3.6, P = .05) and the lack of a written asthma action plan (OR 3.3, P = .03) were independently associated with frequent visits to the ED. We conclude that a substantial proportion of the patients that visit the ED are FV. These patients are more likely to have hospital admission in the past year, to use a home nebulizer, and to lack a written asthma action plan. They should be considered the most important target for asthma education.  相似文献   
37.
Abstract:  We describe a patient with acquired alpha-thalassemia myelodysplastic syndrome (ATMDS). A previously healthy 66-year-old man presented with hemoglobin of 9.3 g/dL, mean corpuscular volume 59 fL, and a bone marrow aspirate with increased erythroid precursors and hypolobulated megakaryocytes. Hemoglobin H inclusions were seen in most red cells after 1% brilliant cresyl blue supravital stain of the peripheral blood. At the molecular level, we identified of a novel mutation in the most 3' exon of the ATRX gene ( C GA→ T GA substitution in codon 2407) resulting in a premature termination codon (p.R2407X). This case provides further evidence for a link between ATRX mutations and ATMDS, and suggests a possible role for the conserved Q-box element in ATRX function.  相似文献   
38.
Effects of rufloxacin in Salmonella typhimurium infection in mice.   总被引:1,自引:0,他引:1  
This study was undertaken to investigate the efficacy of rufloxacin, a new quinolone which is interesting due to its pharmacokinetics characterized by a long plasma half-life, in the treatment of systemic salmonella infections in the mouse typhoid model. Innately susceptible BALB/c and resistant CBA mice were used to investigate the efficacy of rufloxacin in controlling systemic salmonella infections when given for brief or prolonged periods. The present study shows that rufloxacin is not only very effective on both mouse strains, but can completely eradicate the salmonellae from livers and spleens when given early in the infection of CBA resistant mice.  相似文献   
39.
The aim of the present study was to investigate the existence of alterations of the blood-brain barrier (BBB) permeability in rats injected with centrally acting drugs, by calculating a unidirectional blood-to-brain transfer constant (Ki) for the circulating tracer [14C]-alpha-aminoisobutyric acid. The intraperitoneal (i.p.) injection of the dopaminergic antagonist haloperidol (1 mg kg-1) did not modify the regional BBB permeability. When the cholinomimetic agent arecoline hydrobromide (6.25 mg kg-1) was injected i.p. into methylatropine-pretreated rats, it induced a significant decrease of Ki values within the frontal cortex, parietal cortex, striatum and brain-stem. Our findings emphasize two concepts: (1) centrally acting drugs, such as arecoline, can induce changes in the BBB permeability, through several mechanisms; (2) there is no predictable correlation of drug stimulation of specific brain neuronal pathways and changes in the permeability of the BBB.  相似文献   
40.
From September 1984 to December 1989, 38 patients of pediatric age with localized bone sarcomas received intraoperative radiotherapy (IORT) as part of a multidisci plinary treatment program. The age ranged from 6 to 21 years. The tumor histologies were 22 osteosarcomas and 16 Ewing's sarcomas. Thirty-four had initial primary disease (90%) and 4 were treated for local recurrence (10%). IORT was used on 32 untreated patients and in 6 previously treated with external beam radiotherapy (EBR). The IORT field included the surgically exposed tumor bed area. Single radiation doses ranging from 10 to 20 Gy were delivered, using 6–20 MeV electron beams. The median follow-up time for the entire group is 25 months (2–65+ months). The projected 5-year disease-free and overall survival rates are 65% and 69%, respectively. One patient developed a local recurrence in each histological group: one chondroblastic osteosarcoma and one cervical Ewing's sarcoma. Six patients died from metastatic progression: 3 initially recurrent tumors and three primary disease cases. Severe neuropathy and soft tissue necrosis were seen in some patients as IORT related complications. IORT is a feasible technique to be integrated in multidisciplinary programs that may promote local control in pediatric and adolescent patients with bone sarcomas. Peripheral nerves are dose-limiting tissue structures for IORT.  相似文献   
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