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181.
182.
BACKGROUND: Natural antibodies (NAbs) against a terminal alpha1-3 galactosyl (alphaGal) epitope have been identified as the major human anti-pig NAbs. METHODS AND RESULTS: We used two synthetic alphaGal trisaccharides--type 6 (alphaGal6) and type 2(alphaGal2)--linked to an inert matrix to remove NAbs from human plasma in vitro. Flow cytometry indicated that an average of 85% of the NAb binding activity was depleted by adsorption with alphaGal6. By measuring the binding of NAbs to pig peripheral blood mononuclear cells and bone marrow cells, we demonstrated that alphaGal6 was more effective than alphaGal2 in removing NAbs, and the combination of alphaGal6 + alphaGal2 did not further increase removal of NAbs. The specificity of the removal of NAbs (IgM and IgG) reactive with the alphaGal epitope by alphaGal6 matrix was shown by enzyme-linked immunosorbent assay. In vivo studies in nonhuman primates compared plasma perfusion through a alphaGal6 immunoaffinity column with hemoperfusion through a pig liver for changes in blood pressure, hematocrit, platelets, and NAb adsorption. CONCLUSIONS: Both methods reduced the level of anti-pig IgM and IgG xenoreactive antibodies to nearly background, but column perfusion caused less hypotension and reduction in platelets than liver perfusion. Four pig kidneys transplanted into monkeys after column perfusion did not undergo hyperacute rejection, remaining functional for 2-10 days, with a mean functional period of 7 days, demonstrating that a pig kidney can support renal function in a primate. 相似文献
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184.
JS Macpherson J Cummings I Meikle EP Miller JF Smyth 《Canadian Metallurgical Quarterly》1997,33(2):280-283
The effect of the novel topoisomerase I inhibitor NU/ICRF 505 (20 microM, approximate IC50 concentration) on the cell cycle was studied by flow cytometry in four Chinese hamster ovary (CHO) cell lines. Postdrug treated cells were incubated with optimal concentrations of cytochalasin B to prevent re-entry of daughter cells into the cell cycle. NU/ICRF 505 had no significant effect on cell cycle distribution in the parent cell line (CHO-K1) and two mutants hypersensitive to topo II inhibitors (ADR-1, ADR-3), all of which express similar levels of topo I protein. In the drug-resistant variant ADR-r, which overexpresses topo I 2-fold, a significant accumulation of cells in G1 phase was recorded. These results are broadly consistent with the cell cycle effects expected in CHO cells by a classic topo I poison (camptothecin) and add weight to the view that NU/ICRF 505 induces cell death primarily through topo I inhibition. 相似文献
185.
EP Kudriavtsev SI Miroshin SV Semenov AS Snigorenko IA Sidorovich 《Canadian Metallurgical Quarterly》1997,(3):36-41
The functional status of the oxidative-antioxidative system was studied in 72 patients after vast cancer operations. Traditional surgical treatment and its combination with intraoperative irradiation were shown to lead to tense antioxidative defense and to suppressed T-cell immunity and to call for antioxidative and immunomodulating therapy. High intraoperative blood loss complicated by hemorrhagic shock injured the oxidative-antioxidative system greatly. The magnitude of this damage correlated with the rate of prehypoxia. Addition of the potent antioxidant Ceruloplasmin to the drug regimen normalized a recovery period, helped to correct posthypoxic multiorgan insufficiency, to recover oxidative-antioxidative balance, and to decrease the incidence of pyoinflammatory complications. Patients with endogenous intoxication showed activated lipid peroxidation, decreased functional activity of antioxidative defense components and of T-cell immunity in homeostasis. The use of Ceruloplasmin and Laprot had pronounced antiinflammatory and detoxifying effects on the patient's body and activated its antioxidative defense. 相似文献
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MS Lapayowker I Barash R Byrne J Change G Dodd C Farrell JD Haberman HJ Isard B Threatt 《Canadian Metallurgical Quarterly》1976,38(5):1931-1935
The thermal and graphic criteria which should be used to evaluate breast thermograms are outlined. Thermograms are then categorized as normal, suspicious, or abnormal on the basis of the criteria outlined. It is hoped that these criteria can be used widely to standardize breast thermographic evaluation. 相似文献
188.
Central hypoventilation syndrome (CHS) is a disorder characterized by little or no ventilatory or arousal sensitivity to hypercapnia and variable reactivity to hypoxemia, with little or no hypoxic arousal responsiveness. CHS may be congenital or acquired and can be idiopathic or secondary to a known central nervous system abnormality. Infants often present with life-threatening apnea during quiet sleep and develop severe respiratory acidosis because of the inadequate response to hypercapnia and hypoxia. Long-term treatment usually involves use of mechanical ventilation during sleep. 相似文献
189.
The cases of two patients with continent ileostomies are presented. These illustrate the problems encountered with detachment of the pouch from the abdominal wall resulting in angulation of the efferent loop of the pouch in relation to the nipple valve and difficulty intubating the pouch. Both patients required operative correction of the separation. Several suggestions are made in order to prevent or decrease the incidence of the complications. Removal of a peritoneal strip around the efferent loop of the pouch appears to facilitate adequate fixation of the pouch to the anterior abdominal wall. 相似文献
190.
EP Lopes AE Silva H Sette Junior RX Guimar?es ML Ferraz 《Canadian Metallurgical Quarterly》1995,37(5):455-460
This study was undertaken to investigate the presence of autoantibodies in patients with chronic viral hepatitis B and C, before, during and after interferon-alpha (IFN-alpha) therapy and to study their relation to dose and type of IFN-alpha and response to treatment. Fifty patients with chronic hepatitis were divided in two groups, a control-group of 21 patients (10 type B and 11 type C) who were followed for 6 months without treatment and an IFN-group consisting of 29 patients (8 type B and 21 type C) who received IFN therapy for 6 months. Serum samples were tested for a range of antibodies at the start of the study, during therapy and at the end of the 6 month period. Antibodies tested for included: antinuclear, smooth muscle, antimitochondrial, parietal cell and thyroid microsomal. Four (8%) of the total patient group had autoantibodies at the beginning of the study (two in each group). During the follow-up period no patient in the control group developed antibodies compared with 3 (11%) patients in the treatment group. Autoantibodies developed in patients treated with higher doses of IFN and were found in those patients who tended to show a poor response to IFN-therapy. Further studies are needed to establish the relationship between poor response to IFN-alpha and development of autoantibodies. 相似文献