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991.
992.

OBJECTIVE:

It has been suggested that vascular access operations should only be performed in high-volume centres to ensure good outcomes. Vascular access operations have been routinely performed in the Cayman Islands since 2005. However, with an estimated population of 45,000 persons, only a small number of patients require vascular access in any given interval. A cost-benefit analysis of this practice was performed.

METHODS:

All patients who had vascular access operations over four years were retrospectively identified. Two groups were defined – the local group, who had operations performed by surgeons in the Cayman Islands, and the offshore group, who were transferred off the island and had operations overseas. Cumulative cost, morbidity, patency and failure rates were compared. Significance was considered present with a two-tailed P≤0.05.

RESULTS:

There were 14 patients in the local group and 22 in the offshore group. The mean cost of access creation was 6.9 times greater in the offshore group (US$26,883.36 versus US$3,913.33; P<0.001). The likelihood of the use of arteriovenous grafts was significantly greater in the offshore group (P=0.04). When therapeutic outcomes were compared, there were no differences in primary or secondary failure, primary or secondary patency, or overall access-specific morbidity.

CONCLUSIONS:

In the present setting, vascular access creation exceeded all the goals set by the National Kidney Foundation Kidney Disease Outcomes Quality Initiative and the Fistula First Breakthrough Initiative. Compared with overseas centres, this is being achieved at a significantly lower cost, with a greater likelihood of native fistula use and similar therapeutic outcomes.  相似文献   
993.
994.
995.
After kidney transplantation, occurrence of anemia in the early post‐transplant period (<1 month) is high and arises out of issues that are multifactorial. We performed a retrospective single‐center study to assess whether delivery of high doses of erythropoietin‐stimulating agents (ESA) within the first week of kidney transplantation, translates at 1 month post‐transplant, in to causing less anemia and whether it has an impact on allograft function. Ninety‐nine patients were not given ESA (group I), whereas 82 were (250 IU/kg/week; group II). All patients had similar pretransplant and baseline (day 0) variables. Similar numbers of group II patients were still receiving ESA by day 14 (97.5%) and day 30 (89%). Respective figures for group I were 27% and 27%. Independent factors for anemia at 1 month post‐transplant included: being male subject, treatment for hypertension at pretransplant, anemia at transplant, a higher mean corpuscular volume at transplant, and an induction therapy using antithymocyte globulins. Independent predictive factors for lower creatinine clearance included being female subjects, having a donor aged >50 years, being a recipient aged >50 years, not treated for hypertension at pretransplant, and no post‐transplant ESA therapy. High doses of ESA within the first month of kidney transplantation have no impact on anemia or renal function by 1 month post‐transplant.  相似文献   
996.
This sequential study evaluated two strategies regarding human cytomegalovirus (HCMV) infection/disease in HCMV‐seropositive de novo kidney‐transplant patients. The first cohort of patients (group 1; n = 132) was monitored sequentially for HCMV DNAemia; if it was positive (a cut‐off at 3 log10copies/ml), the patient was given pre‐emptive IV ganciclovir therapy (10 mg/kg/day for 3 weeks). The second cohort consisted of 150 patients (group 2) who were given valganciclovir (VGC) prophylaxis (900 mg/day) for the first 3 months posttransplantation. During the mean follow‐up of at least 2 years for both cohorts, VGC prophylaxis resulted in a significant decrease in both CMV infection (68.9% vs. 33.3%; P < 0.001) and disease (9.8% vs. 2.68%, P = 0.021). Factors associated with HCMV reactivation in multivariate analysis were (i) no HCMV prophylaxis; (ii) recipient’s age; (iii) being placed on ciclosporine A and mycophenolic acid from the beginning of transplantation (iv) donor HCMV‐seropositivity; and (v) being a male recipient. No cases of ganciclovir resistance were detected in the prophylactic group. HCMV prophylaxis had no impact on 2‐year patient/graft survival or on kidney‐allograft function. We conclude that VGC‐prophylaxis can be reasonably used to treat HCMV‐seropositive kidney‐transplant recipients.  相似文献   
997.
998.
In chronic myeloid leukemia (CML), cytogenetic abnormalities found in addition to the t(9;22) translocation may impact the response to therapy. Loss of the Y chromosome is generally overlooked in this context, owing to its relatively frequent occurrence in healthy elderly patients. In this multicenter retrospective study, the outcome after imatinib treatment of 30 CML patients with karyotype showing Y chromosome loss (Y−) was compared to 30 Y+ control males diagnosed and treated at the same time in the same institutions. Y− patients had significantly delayed cytogenetic and molecular responses, lower event-free survival and shorter overall survival than Y+ patients. The negative impact of this abnormality was particularly marked when it occurred in a sub-clone (clonal evolution) rather than in all mitoses. These data indicate that loss of the Y chromosome should be taken into account in the prognostic evaluation of chronic myelogenous leukemia patients.  相似文献   
999.
1000.
The rate of biosynthesis and turnover of the plasma protein fibrinogen is a marker of metabolic signaling in aging and disease. The rate in the young normal human subject of 0.260 mg/ml/24 h increases to 0.378 in older normal subjects and to 0.466 in age matched coronary thrombosis patients measured by endogenous labeling of fibrinogen with l-glutamic acid-C14. The increased rate of fibrinogen turnover has been traced to generation of fibrin by labeling the polymers with glycine C14 ethyl esters in the presence of activated fibrin stabilizing factor. Circulating fibrin increased 520% above normal in ischemic thrombotic cerebrovascular disease. Long chain saturated free fatty acids (FFA) exercise not only primary control over incorporation of Cl4 labeled amino acids into the fibrinogen structure but also activate the cascade sequence of reactions which convert fibrinogen into occlusive fibrin polymers. FFA are normally bound and transported by plasma albumin to mitochondrial sites of energy metabolism. Albumin synthesis declines with aging. This decline is associated with increased plasma levels of FFA resulting in an increase in the plasma FFA/albumin ratio. Correction of this ratio in vitro by restoration of a normal FFA/albumin ratio restores a normal level of fibrinogen synthesis by human hepatocytes.  相似文献   
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