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991.
Perioperative vasospasm during cardiovascular surgery is a challenging problem. Several vasodilator agents are frequently utilized for its prevention in surgical practice. Magnesium and diltiazem both have known potential vasorelaxant effects. We planned to compare the efficacy of diltiazem and magnesium in relieving phenylephrine-precontracted rat aortic rings. Ten young adult female Wistar albino rats weighing 230-260 g were used in this study. The aortic rings in the organ bath equilibrated and reached their baseline tension. Precontraction was induced by 0.001 mmol/l phenylephrine and cumulative concentration-relaxation curves were obtained by consecutively increasing the addition of either diltiazem (10(-6)-0.1 mmol/l) or magnesium (0.1-10 mmol/l). The mean maximal relaxation responses observed by diltiazem and magnesium on separate aortic rings were 90 ± 3 and 53 ± 2%, respectively. The calculated EC50 of diltiazem was 0.01035 mmol/l, whereas the EC50 of magnesium was 4.064 mmol/l (P < 0.05). Both magnesium and diltiazem produced vasorelaxation on phenylephrine-precontracted rat aortic rings in this study, but the potency of diltiazem regarding the EC50 value was significantly higher than that of magnesium. Magnesium could be a candidate together with diltiazem to inhibit vasospasm on arterial grafts during coronary bypass surgery.  相似文献   
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OBJECTIVES: To study the characteristics and the predictors of survival observed in our pediatric live-donor renal transplant recipients with an allograft that functioned for more than 10 yr. METHODS: One hundred fifteen children underwent renal transplantation between 1976 and 1995. Of these, 30 had functioning allografts for more than 10 yr (range, 11-18). The patients included 18 males and 12 females, with a mean age at transplantation of 13 yr (range, 5-18). Characteristics of the patients, data on graft survival, and determinants of outcome were obtained by reviewing all medical charts. RESULTS: At most recent follow-up (January 2005), the mean daily dose of azathioprine was 1.2 mg/kg (range, 1-2) and that of prednisone was 0.16 mg/kg (range, 0.1-0.2). Mean creatinine clearance was 72 mL/min per 1.73 m(2) (range, 45-112). Acute rejection occurred in 14 (47%) patients. Seven patients had one episode, five had two episodes, and two had three episodes of acute rejection. Three patients (10%) developed malignancy. A substantial proportion of patients (44%) were short, with a height standard deviation score (SDS) less than -1.88, which is below the third percentile for age and gender. One quarter of the patients, more commonly the females, were obese. Other complications included osteoporosis in 16 (53%) patients, avascular bone necrosis in four (13%), post-transplantation diabetes mellitus in three (10%), and hypertension in 18 (60%). Twelve (40%) patients were married and 27% had children post-transplantation. The independent determinants of long-term graft survival were acute rejection and post-transplant hypertension. CONCLUSION: Despite good renal function, long-term pediatric renal transplant survivors are at risk of significant morbidity. The determinants of long-term graft survival are acute rejection and post-transplant hypertension.  相似文献   
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The current knowledge base lacks evidence about situational- and surface-level personality variables and their impacts on job embeddedness and proclivity to be absent from work. With this recognition, drawing from the hierarchical personality model and fit theory as well as job embeddedness theory, our paper explores the influences of job resourcefulness (JR) and customer orientation (CO) on job embeddedness and propensity to be absent from work. We tapped time-lagged data gathered from hotel customer-contact employees in the United Arab Emirates to assess the aforementioned linkages via structural equation modeling. CO is a complete mediator between JR and job embeddedness, while job embeddedness completely mediates the linkage between CO and absence intentions. Specifically, hotel employees who can work under a resource-depleted environment are high on CO and therefore display job embeddedness at elevated levels. In addition, customer-oriented hotel employees have higher job embeddedness and therefore exhibit lower absence intentions.  相似文献   
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Basaloid follicular hamartoma is not a well-recognized clinical entity and has often been diagnosed as trichoepithelioma or basal cell carcinoma. It is a unique benign follicular tumour which comprises a variety of clinical manifestations. We present the case of a 24-year-old male with unilateral basaloid follicular hamartoma present at birth and later misdiagnosed as basal cell carcinoma. Histological features of basaloid follicular hamartoma are not always diagnostic and clinico-pathological correlation is particularly important to distinguish this benign hamartoma from other basaloid tumours including basal cell carcinoma. Continuous follow-up of our patient did not reveal any clinical or histological malignant transformation.  相似文献   
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