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101.
Z Türkyilmaz K S?nmez AC Ba?aklar B Demiro?ullari V Numano?lu G Ekingen A Dursun MA Altin N Kale 《Canadian Metallurgical Quarterly》1997,32(12):1728-1731
BACKGROUND/PURPOSE: Pulse oximetry has been proposed as an appropriate and feasible technique in the assessment of intestinal ischemia in recent years. In this study the authors aimed to assess the reliability of anastomoses in the dog small intestine in which there is graded irreversible ischemia as measured by pulse oxymeter. METHODS: In a control group of four dogs, without any devascularization, three small bowel anastomoses were formed in each dog. The study group consisted of 12 dogs. In each animal three intestinal segments with different levels of ischemia were created by ligating the marginal vessels proximally and distally in sequence beginning from the midpoint of the segmental vascular arcade. Preanastomotic pulse oximeter readings between 80% and 90% were assigned to mild ischemia, 70% and 80% to moderate, and 60% and 70% to severe ischemia group. Pulse oximetry measurements were obtained from probes applied to the antimesenteric serosal surfaces at the midpoint of small intestinal segments. A total of 48 intestinal segments (12 nonischemic in the control group and 36 with three different levels of ischemia in the study group) were transected in the midpoint and anastomosed in double layers. Postanastomotic SaO2 values were also noted. The anastomoses were evaluated 48 hours later macroscopically if there was any leakage, and biopsy specimens were obtained for histopathologic ischemic gradings. All results were studied statistically. RESULTS: Histopathologic grades between each group were statistically different (P < .01 for each comparison) except for control and mild ischemia groups (P > .05), worsening as the level of ischemia increased. Pre- and postanastomotic pulse oximetry measurements correlated very well with the histological gradings (r = -0.90, P < .001 and r = -0.93, P < 0.001 respectively). Number of anastomotic leakages were none in control, one in mild, nine in moderate, and 12 (all of the anastomoses) in severe ischemia groups. In the moderate ischemia group with an average preanastomotic pulse reading of 76.75%, each of the leaking anastomoses had a postanastomotic pulse measurement of lower than 70%. The finding that the difference between histopathologic grades of control and mild ischemia groups with average preanastomotic pulse measurements of 96% and 85%, respectively is not statistically significant enables us to suggest that a saturation of at least 85% is necessary for a reliable anastomosis. CONCLUSION: These results suggest clearly that anastomotic reliability can be predicted objectively with pulse oximetry. 相似文献
102.
GP Rossi G Albertin S Bova AS Belloni F Fallo U Pagotto L Trevisi G Palù AC Pessina GG Nussdorfer 《Canadian Metallurgical Quarterly》1997,138(10):4421-4426
103.
Secretory middle ear otitis is of difficult assessment in children with severe hearing impairment. This otitis, very frequent in infants and children, influences negatively the auditive capacity and apprenticeship as well. Our study deals with the prevalence and severity of the secretive middle ear otitis in an scholar population handicapped by a heavy hypoacusia. Demographically, etiologic and seasonal correlations are considered in the paper. The outcome shows a high incidence of the condition, an inversely relation with the age, an evident seasonal distribution and the absence of correlation between etiology of middle ear disease and sensorineural deafness. 相似文献
104.
W Terpstra H Rozemuller DA Breems EJ Rombouts A Prins DJ FitzGerald RJ Kreitman JJ Wielenga RE Ploemacher B L?wenberg A Hagenbeek AC Martens 《Canadian Metallurgical Quarterly》1997,90(9):3735-3742
We studied the cell kill induced by granulocyte-macrophage colony-stimulating factor (GM-CSF ) fused to Diphtheria Toxin (DT-GM-CSF ) in acute myeloid leukemia (AML) samples and in populations of normal primitive hemopoietic progenitor cells. AML samples from three patients were incubated in vitro with 100 ng/mL DT-GM-CSF for 48 hours, and AML cell kill was determined in a proliferation assay, a clonogenic assay colony-forming unit-AML (CFU-AML) and a quantitative long-term bone marrow (BM) culture ie, the leukemic-cobblestone area forming cell assay (L-CAFC). To measure an effect on cells with in vivo leukemia initiating potential DT-GM-CSF exposed AML cells were transplanted into immunodeficient mice. In two out of three samples it was shown that all AML subsets, including those with long-term abilities in vivo (severe combined immunodeficient mice) and in vitro (L-CAFC assay) were reduced in number by DT-GM-CSF. Cell kill induced by DT-GM-CSF could be prevented by coincubation with an excess of GM-CSF, demonstrating that sensitivity to DT-GM-CSF is specifically mediated by the GM-CSF receptor. Therefore, binding and internalization of GM-CSF probably occur in immature AML precursors of these two cases of AML. The third AML sample was not responsive to either GM-CSF or DT-GM-CSF. The number of committed progenitors of normal bone marrow (burst-forming unit-erythroid, colony-forming unit granulocyte- macrophage, and cobble stone area forming cell [CAFC] week 2) and also the number of cells with long-term repopulating ability, assayed as week 6 CAFC, were unchanged after exposure to DT-GM-CSF (100 ng/mL, 48 hours). These studies show that DT-GM-CSF may be used to eliminate myeloid leukemic cells with long-term potential in vitro and in immunodeficient mice, whereas normal hemopoietic stem cells are spared. 相似文献
105.
106.
AC Barretto M Wajngarten JB Serro-Azul H Pierri A Nussbacher OC Gebara 《Canadian Metallurgical Quarterly》1997,69(6):375-379
The clinical hemostatic effect of tranexamic acid mouthwash after oral surgery was evaluated in 47 patients receiving oral anticoagulant therapy. Surgery was performed after the anticoagulant medication was reduced in 15 patients (control group) and with no change in anticoagulant therapy in 32 patients (test group). The only statistical difference between the two treatment groups at baseline was the level of anticoagulation, which was significantly higher in the test group. There was no significant difference between the two treatment groups in the incidence of bleeding after oral surgery. The results indicated that a combination of local antifibrinolytic therapy and a local hemostatic agent is effective in preventing postoperative bleeding after oral surgery in patients treated with anticoagulants. 相似文献
107.
Rotaviruses and reoviruses are involved in human and animal diseases. It is known that both viruses penetrate the gastrointestinal tract but their interaction with phagocytic cells is unknown. To study this interaction, peritoneal resident phagocytic cells were used and rotavirus and reovirus replication in peritoneal phagocytic cells was observed. However, rotavirus replication in these cells led to the production of defective particles since MA-104 cells inoculated with rotavirus phagocytic cell lysate did not show any evidence of virus replication. On the basis of these results, we suggest that, although reovirus dissemination may be helped by these phagocytic cells, these cells may control rotavirus infection and probably contribute to the prevention of its dissemination. 相似文献
108.
109.
110.
D Grandér R Hultcrantz O Weiland B Xu O Sangfelt AC Bj?rklund R Befrits M Bj?rkholm A Gruber N Kinnman O Reichard A Widell S Einhorn 《Canadian Metallurgical Quarterly》1996,31(6):604-611
BACKGROUND: The mechanism behind the antiviral action of interferon (IFN) therapy in chronic hepatitis C virus (HCV) infection is not well understood, and, furthermore, few factors have been shown to be good predictors of a favourable response to IFN treatment in chronic HCV infection. METHODS: Freshly explanted liver cells and peripheral blood mononuclear cells (PBMC) from 80 patients with chronic HCV infection were used to study the capacity of IFN to induce the enzyme 2',5'-oligoadenylate synthetase (2'5'-AS) in vitro. The HCV genotype was determined in 53 patients. The induction of 2'5'-AS was correlated to the results of IFN-alpha treatment in 36 patients. RESULTS: Normalization of transaminases during IFN treatment was significantly associated with 2'5'-AS levels in liver cells cultured in the absence of IFN. A similar tendency, although not statistically significant, was found for IFN-induced levels of 2'5'-AS in liver cells. No such associations were found when PBMC were analysed. Six patients showed a sustained biochemical response. These six did not deviate significantly from the remaining patients with regard to base-line or IFN-induced levels of 2'5'-AS in liver cells or PBMC. Eradication of HCV RNA during IFN treatment did not correlate with 2'5'-AS levels in liver cells. Comparison of HCV genotype and clinical response showed that patients with genotype 3a had the most favourable outcome. No association was found between liver histology and treatment outcome. CONCLUSION: These data imply that direct effects of IFN on liver cells are of importance for the response to IFN treatment. 相似文献