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OBJECTIVE: To identify the surgical approaches and risk factors which influence longevity of right ventricle to pulmonary artery (RV-PA) conduits following first reoperation for obstruction. METHODS: Between January 1993 and August 2003, 114 patients underwent 141 reoperations for RV-PA conduit obstruction. Diagnoses included 'Truncus Arteriosus' (n=52), 'Pulmonary atresia/Tetralogy of fallot' (n=39), 'Double outlet right ventricle' (n=10), 'Transposition of great arteries, VSD, and pulmonary atresia' (n=9), and the 'Ross operation' (n=4). All patients had undergone a previous biventricular repair. The first reoperation for conduit obstruction was performed in 112 hospital survivors by: total conduit replacement (Group A, n=73) with valved (homograft=10 and xenograft=54) or non-valved (n=9) conduit, and patch enlargement of the obstructed RV outflow tract with preservation of the posterior and sides of the conduit wall after removing of the fibrocalcific peel and degenerated valve (Group B, n=39). Mean age at first reoperation was 8.8+/-6.7 and 7.5+/-5.3 years in patients of groups A and B, respectively. Seven patients in Group A and 18 in Group B required a second reoperation and two patients in Group B a third reoperation. RESULTS: There were two hospital deaths and no late deaths. Mean follow-up was 5.8+/-3.2 years. Risk factors for second reoperation by univariate analysis were: homograft conduit use (P=0.004), Group B surgical approach (P=0.0001), higher RV-PA systolic pressure gradient at discharge (P=0.02), and age <5-years-old (P=0.01). Multivariate analysis showed that inclusion in Group B and younger age (<5-years-old) at repair were independent risk factors for second reoperation. Group B surgical approaches had higher RV-PA systolic pressure gradient at discharge (P=0.02) and required more PA bifurcation repair at the time of second reoperation (P=0.05). Freedom from second reoperation for conduit obstruction was significantly higher in Group A patients at 5 and 8 years (P<0.04) and those with xenografts rather than homograft (P=0.04). CONCLUSIONS: Our results support the optimal surgical approach for RV-PA conduit obstruction is total replacement with a xenograft. RV outflow reconstruction by other techniques without complete dissection of PA bifurcation does not completely relieve the stenosis and could cause early restenosis. Higher systolic gradients at discharge and younger age at first reoperation are predictors of earlier reoperation.  相似文献   
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BACKGROUND: We have noted an unexpectedly high incidence of prostate cancer in our heart transplant recipients (HTR). METHODS: We conducted a retrospective review of patients after heart transplantation to investigate the prevalence, treatment, and outcome of prostate cancer diagnosed after systematic screening (study group). We compared them with case-matched HTR (control). RESULTS: Among 702 recipients, 15 patients had elevated prostate-specific antigen (PSA) levels. Fourteen cases of prostate cancer were diagnosed and treated. The median time between transplantation and prostate cancer diagnosis was 73 months. No patient was diagnosed in a locally advanced (>T2) or metastatic stage. Eleven patients (78.6%) received curative treatment. During follow-up (median, 44 months), 1 patient died from prostate cancer. The survival rate between the study and control groups did not differ. CONCLUSION: Routine PSA testing is recommended as a screening test for prostate cancer in patients after heart transplantation. We believe this could also result in detection of early stages of prostate cancer, thus allowing curative treatment, and achieving similar survival to other case-matched HTR with no prostate cancer.  相似文献   
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Odds ratio was used to evaluate relationship between sepsis in cattle less than 1 year old and mastitis in cows and erythrocyte glutathione peroxides (GSH-PX) activity as an indicator of selenium status. Data were from 178 blood samples collected from referred cases to Urmia University, Veterinary Teaching Hospital. Low activity of GSH-PX was significantly associated with higher odds of developing sepsis (P=0.005) in young cattle and mastitis (P=0.044) in adult cows. The odds ratios for the low activity of GSH-PX on incidence of sepsis and mastitis were 4.74 and 3.95, respectively. Selenium deficiency was associated with sepsis in young cattle and mastitis in cows, i.e., cattle with low activity of erythrocyte GSH-PX were at increased risk of sepsis and mastitis.  相似文献   
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International Urology and Nephrology - The aim of this study is to evaluate the intra/perioperative fluid management and early postoperative outcomes of patients who underwent radical cystectomy...  相似文献   
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Anti-oxidant effect of flavonoids on hemoglobin glycosylation   总被引:7,自引:0,他引:7  
A high glucose concentration has been found to lead to the glycosylation of amino groups of lysine residue in proteins. The addition of reducing agent not only prevents this reaction but also reverses it. On the other hand, flavonoids which found in plant sources have antioxidant properties. Since the glycosylation of protein is an oxidation reaction, therefore, antioxidants should be able to prevent this reaction. In this study, the best concentration and time to incubate glucose with hemoglobin was investigated. Then the glycosylation degree of hemoglobin in the presence of flavonoids and their absence was measured by means of a colorimetric method. Different concentration of flavonoids (Quercetin, Rutin, Kaempferol) were used. The preventing effect on hemoglobin glycosylation by the three concentrations; 0.5, 5, 10 micrograms/ml was estimated as follows: for Rutin; 11%, 27%, 42%, Quercetin; 3%, 37%, 52%, Kaempferol; 10%, 12%, 15% respectively. So, the in vivo effect should be investigated and then plants that containing flavonoids can be utilized to prevent or treat complication of diabetes.  相似文献   
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