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BACKGROUND: We studied the economic impact of cytomegalovirus (CMV) disease and its effective reduction with antiviral prophylaxis in liver transplant recipients. METHOD: Analysis of institutional charge data accumulated during a prospective, randomized, controlled trial comparing oral acyclovir 800 mg four times daily for 120 days (ACV) and intravenous ganciclovir 5 mg/kg every 12 h for 14 days followed by ACV for 106 days (GCV) was performed. RESULTS: Liver transplant recipients who developed CMV disease had significantly higher charges (median: $148,300) than those who developed asymptomatic CMV infection ($119,600) or experienced no CMV infection ($114,100) (P<0.01). A multiple linear regression analysis indicated that CMV disease is associated with a 49% increase in charges, independent of other factors influencing increased hospitalization charges. In CMV-seronegative patients who received a CMV-seropositive donor organ, GCV prophylaxis was associated with a significant reduction in charges, as compared to ACV prophylaxis ($113,900 vs. $153,300, respectively; P=0.02). CONCLUSIONS: CMV disease is an independent risk factor for increased resource utilization associated with liver transplantation. The use of an effective prophylactic antiviral regimen provides savings in health care resources, particularly in patients at high risk for developing CMV disease.  相似文献   
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Kim WG  Na MH  Kim JH 《Artificial organs》2000,24(9):729-733
An effective in vitro protocol for the investigation of thrombogenicity can provide many advantages in the development of mechanical circulatory assist devices. Strict avoidance of air contact with blood recently was proposed for reliable in vitro evaluation. This study was performed to confirm the necessity of avoidance of air contact for the in vitro test of thrombogenicity in a rotary pump. Two sets of mock circuits with the same rotary blood pumps, reservoirs, and connecting tubes were made. In one system, blood came in contact with air while the other did not. The test blood was heparinized at the dose of 1 IU per 1 ml of blood. The tests were terminated at an activated coagulation time of 1.5 times the control value. The levels of hematocrit, platelet, factors VIII and XII, fibrinogen, thromboxane B2, and plasma-free hemoglobin were measured during the procedures. After the experiments, the thrombi formed were observed, measured, and compared with those formed in in vivo circumstances. The tests were repeated 12 times. There were no statistically significant differences between the 2 groups in hematologic parameters and the amounts of thrombi formed. The thrombi observed in both groups showed the same pathologic findings as those formed in vivo with the exception of intermittent multiple air bubbles found in thrombi of the air-contact group. In conclusion, the effect of air contact in the in vitro investigation of thrombogenicity was negligible while the proposed in vitro test models of thrombogenesis in the mechanical circulatory assist device proved to be reliable.  相似文献   
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Jung JS  Lee RH  Koh SH  Kim YK 《Renal failure》2000,22(4):407-421
Ischemic renal injury is associated with defects in transport functions of the proximal tubules and urinary concentration ability. To determine whether alterations in expression of various transporter genes contribute to an impairment in renal functions, the expression of various solute transport genes was analyzed in renal cortex and medulla of rabbits with ischemic acute renal failure. Rabbits were subjected to 60 min of renal pedicle clamping followed by 24, 48, or 72 h of reperfusion. Urine volume and glomerular filtration rate were markedly decreased, which were accompanied by an increase in serum creatinine level and fraction Na+ excretion. Glucosuria and phosphaturia were evident during reperfusion periods. These alterations in renal functions were persisted to 72 h after reperfusion. The Na+-dependent uptakes of glucose and phosphate by brush border membrane vesicles were inhibited by 24 h of reperfusion. mRNA levels for Na+-glucose, Na+-phosphate, and Na+-succinate cotransporter analyzed by RT-PCR were not changed by 60 min of ischemia alone, but were significantly reduced by 24 h of reperfusion. mRNA levels for apical Na+-K+-2Cl- cotransporter, NaCl cotransporter, and turea transporter in the medulla were not changed during reperfusion. Protein levels for AQP2 in the medulla, but not AQP1 in the cortex, analyzed by Western blot were significantly reduced at 24 h after reperfusion. These results suggest that reductions in expression of Na+-cotransporter genes in the proximal tubules may be important factors in the impairment in Na+-dependent reabsorption of solutes and that decrease in AQP2 protein may be involved in defect in urinary concentration ability in rabbits with ischemic acute renal failure.  相似文献   
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