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991.
Effort angina of a 70-year-old man was diagnosed as due to triple coronary vessel disease, and he was scheduled to undergo coronary artery bypass surgery. Preoperative carotid duplex scan revealed more than 75% stenosis of the right internal carotid artery, which was functionally proven to be significantly ischemic on brain single photon emission computed tomography. Although he was neurologically asymptomatic, we chose staged surgery for fear of stroke during coronary artery bypass surgery. He had successful carotid artery stenting first by neurosurgeons; then, 2 months later he underwent uneventful coronary artery bypass surgery. This experience prompted us to report the case.  相似文献   
992.
Chronic allograft nephropathy (CAN) is the leading cause of renal allograft loss in paediatric renal transplant recipients. CAN is the result of immunological and nonimmunological injury, including acute rejection episodes, hypoperfusion, ischaemia reperfusion, calcineurin toxicity, infection and recurrent disease. The development of CAN is often insidious and may be preceded by subclinical rejection in a well-functioning allograft. Classification of CAN is histological using the Banff classification of renal allograft pathology with classic findings of interstitial fibrosis, tubular atrophy, glomerulosclerosis, fibrointimal hyperplasia and arteriolar hyalinosis. Although improvement in immunosuppression has led to greater 1-year graft survival rates, chronic graft loss remains relatively unchanged and opportunistic infectious complications remain a problem. Protocol biopsy monitoring is not current practice in paediatric transplantation for CAN monitoring but may have a place if new treatment options become available. Newer immunosuppression regimens, closer monitoring of the renal allograft and management of subclinical rejection may lead to reduced immune injury leading to CAN in the paediatric population but must be weighed against the risk of increased immunosuppression and calcineurin inhibitor nephrotoxicity.  相似文献   
993.
Adults with autosomal dominant polycystic kidney disease (ADPKD) and PKD1 mutations have a more severe disease than do patients with PKD2 mutations. The aim of this study was to compare phenotypes between children with mutations in the PKD1/PKD2 genes. Fifty PKD1 children and ten PKD2 children were investigated. Their mean age was similar (8.6 ± 5.4 years and 8.9 ± 5.6 years). Renal ultrasound was performed, and office blood pressure (BP), ambulatory BP, creatinine clearance and proteinuria were measured. The PKD1 children had, in comparison with those with PKD2, significantly greater total of renal cysts (13.3 ± 12.5 vs 3.0 ± 2.1, P = 0.004), larger kidneys [right/left kidney length 0.89 ± 1.22 standard deviation score (SDS) vs 0.17 ± 1.03 SDS, P = 0.045, and 1.19 ± 1.42 SDS vs 0.12 ± 1.09 SDS, P = 0.014, successively] and higher ambulatory day-time and night-time systolic BP (day-time/night-time BP index 0.93 ± 0.10 vs 0.86 ± 0.05, P = 0.021 and 0.94 ± 0.07 vs 0.89 ± 0.04, P = 0.037, successively). There were no significant differences in office BP, creatinine clearance or proteinuria. Prenatal renal cysts (14%), hypertension defined by ambulatory BP (27%) and enlarged kidneys (32%) were observed only in the PKD1 children. This is the first study on genotype–phenotype correlation in children with ADPKD. PKD1 children have more and larger renal cysts, larger kidneys and higher ambulatory BP than do PKD2 children. Renal cysts and enlarged kidneys detected prenatally are highly specific for children with PKD1.  相似文献   
994.
Immunoglobulin (Ig) M nephropathy is defined by electron-dense mesangial deposits and mesangial IgM visible by immunofluorescence (IF) without other histopathologic and immunofluorescent microscopic abnormalities. Certain patients have only immuno-positive (IgM+) IF. Children presenting with steroid-dependent or steroid-resistant nephrotic syndrome have a high prevalence of IgM+ IF with or without electron-dense deposits. We reviewed the clinical course of children with steroid-dependent or steroid-resistant nephrotic syndrome who underwent renal biopsy at Texas Children‘s Hospital from 1989 to 2006 to further characterize IgM+ IF in children with nephrotic syndrome. Of the 55 children with steroid-resistant or -dependent minimal change disease (MCD), 23 had IgM+ IF. Of these 23 children, 61% had microscopic hematuria at presentation, 48% (11/23) were steroid-dependent, and 48% (11/23) steroid-resistant (one underwent biopsy prior to steroid therapy). We compared the efficacy of adjuvant treatment with cyclophosphamide and cyclosporine: 18% initially treated with cyclophosphamide obtained remission, while 55% had no response; 83% obtained subsequent remission with cyclosporine. Of those initially treated with cyclosporine, 88% obtained complete or partial remission. IgM+ IF may be surrogate marker for the severity of MCD. Based on our results, children with MCD and IgM+ IF have a better response to cyclosporine than cyclophosphamide.  相似文献   
995.
To study the effects of hypertension and other cardiovascular risk factors on risk of fractures, we carried out a case-control study including 124,655 fracture cases and 373,962 age- and gender-matched controls. The main exposure was hypertension, stroke, acute myocardial infarction, ischemic heart disease, atrial fibrillation, peripheral arterial disease, and deep venous thromboembolism, and the main confounders were use of diuretics, antihypertensive drugs, organic nitrates, vitamin K antagonists, and cholesterol lowering drugs along with other confounders. Hypertension and stroke were the only significant risk factors in both the short-term (OR = 1.27, 95% CI = 1.20–1.34 and 1.24, and 95% CI = 1.16–1.31 for ≤3 years since diagnosis of hypertension and stroke, respectively) and the long-term (OR = 1.11, 95% CI = 1.00–1.23 and 1.09, and 95% CI = 1.02–1.18 for > 6 years since diagnosis of hypertension and stroke, respectively) perspective. Acute myocardial infarction, atrial fibrillation, and deep venous thromboembolism were all associated with a transient increase in the risk of fractures within the first 3 years following diagnosis. Peripheral arterial disease and ischemic heart disease were not associated with an increased risk of fractures. In conclusion, hypertension and stroke seem to be the major cardiovascular risk factors for fractures, whereas acute myocardial infarction, atrial fibrillation, and deep venous thromboembolism seem to be only minor risk factors. The fracture risk in hypertension may explain why antihypertensive drugs as a class effect are associated with a decreased risk of fractures. These drugs may counter some of the deleterious effects of high blood pressure.  相似文献   
996.
Introduction  As life expectancy in the population rises, osteoporotic fractures are seen most frequently in the proximal femur and the vertebral column. In balloon kyphoplasty and vertebroplasty, we have two minimally invasive treatment procedures available. Although they have both been controversially discussed in studies, they have seldom been directly compared. Materials and methods  Between 2002 and 2004, patients with fresh thoracic or lumbar single-segment vertebral compression fractures not involving neurological deficits were treated by balloon kyphoplasty (n = 30) or vertebroplasty(n = 30) using PMMA cement, and the results of the two interventions were compared in a prospective, nonrandomised cohort study. Surgery was indicated when patients had painful, dislocated fractures of type A1 and type A3 according to Magerl’s classification. The outcome of treatment was assessed with special reference to the angle of kyphosis, back pain (VAS), health-related quality of life (SF-36) and complications. Results  At the time of the follow-up examination, significant improvement in the angle of kyphosis was found to have been achieved both by kyphoplasty and by vertebroplasty (P < 0.001 and P = 0.002, respectively). Comparison showed that correction of the angle was significantly (P < 0.001) better in the kyphoplasty group. Both surgical procedures led to significant (P < 0.001) attenuation of the patients’ pain; no difference was observed between the groups in the degree of pain relief achieved. There was no demonstrable correlation in either group between the preoperative pain experienced by the patients and the degree of dislocation of their fractures. In both study groups, the quality of life was in keeping with that of a reference group matched for age and sex. Cement leakage was observed in 7% of patients after kyphoplasty and in 33% of patients after vertebroplasty (P = 0.021). Adjacent-level fractures were checked for, but occurred in only one patient in the vertebroplasty group. Conclusion  The two surgical procedures were both followed by significant pain relief, and the quality of life was similar regardless of the procedure used. Balloon kyphoplasty led to an ongoing reduction of freshly fractured vertebrae and was followed by a lower rate of cement leakage.  相似文献   
997.
Postlactational involution is the process following weaning during which the mammary gland undergoes massive cell death and tissue remodeling as it returns to the pre-pregnant state. Lobular involution is the process by which the breast epithelial tissue is gradually lost with aging of the mammary gland. While postlactational involution and lobular involution are distinct processes, recent studies have indicated that both are related to breast cancer development. Experiments using a variety of rodent models, as well as observations in human populations, suggest that deregulation of postlactational involution may act to facilitate tumor formation. By contrast, new human studies show that completion of lobular involution protects against subsequent breast cancer incidence.  相似文献   
998.
Aminoglycosides have a wide spectrum of gram-negative anti-bacterial activities and are available at low cost, which makes them commonly used drugs, especially for patients with cystic fibrosis (CF), who often suffer from chronic lung infections from Pseudomonas aeruginosa. Unfortunately, this treatment seems to have resulted in an increased incidence of acute renal failure (ARF) in patients with CF. A recent case–control study investigated risk factors for ARF in CF patients and suggested intravenous use of gentamicin as the prime culprit. Moreover, in most cases, at least one other risk factor, such as CF-related diabetes, pre-existing renal failure, dehydration or concurrent use of other nephrotoxic drugs, was present. We comment on the renal handling of aminoglycosides and the possible mechanisms of toxicity, as well as strategies for risk minimisation.  相似文献   
999.
We report the results of a primary total hip arthroplasty (THA) in 7 patients with advanced active tuberculous arthritis of the hip and had lost the chance of preserving the hip without replacement surgery. Tuberculosis was confirmed in all cases by the culture or histological examination. All patients were treated with primary THA followed by antituberculous medications for 1 year. Cementless stems and sockets were used in all patients. The average follow-up period was 4.8 years. The reactivation of the infection was not detected in all cases. The result was excellent in all patients according to the Harris Hip Score. Total hip arthroplasty in the tuberculous hip is a safe procedure and produces superior functional results compared with resection arthroplasty or arthrodesis. The results of primary THA in the selected patients was satisfactory as they rapidly recover from the disease.  相似文献   
1000.
Benign schwannoma of the pancreas   总被引:2,自引:0,他引:2  
Reported cases of intrapancreatic schwannomas have recently increased in the literature. However, none of these cases were diagnosed clearly as schwannoma preoperatively. We herein describe the clinicopathologic findings of a solitary benign schwannoma occurring in the head of the pancreas. Additionally, the differential diagnosis versus other cystic- and solid-appearing pancreatic masses is briefly discussed.  相似文献   
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