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OBJECTIVES: The primary objective of the IDEAL study is to determine whether the timing of dialysis initiation has an effect on survival in subjects with end-stage renal disease (ESRD). The secondary objectives are to determine the impact of "early start" versus "late start" dialysis on nutritional and cardiac morbidity, quality of life, and economic cost. DESIGN: Prospective multicenter randomized controlled trial. Patients are randomized to commence dialysis at a glomerular filtration rate (by Cockcroft-Gault) of either 10-14 mL/minute/1.73 m2 ("early start") or 5-7 mL/min/1.73 m2 ("late start"), with stratification for dialysis modality (hemodialysis vs peritoneal dialysis), study center, and the presence or not of diabetes mellitus. SETTING: Dialysis units throughout Australia and New Zealand. PATIENTS: Patients with ESRD commencing chronic dialysis therapy. OUTCOME MEASURES: Three years from randomization, all-cause mortality, morbidity, and economic impact; structural and functional cardiac status, nutritional state, and quality of life will be assessed. RESULTS: To date, 388 patients of a minimum 800 patients have been entered and randomized into the study. Current recruitment rates suggest sufficient patients will be enrolled by December 2004 and follow-up completed by December 2007. CONCLUSIONS: The IDEAL study will provide evidence for the optimal time to commence dialysis.  相似文献   
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BACKGROUND: Treatment of human immunodeficiency virus (HIV) with protease inhibitors (PIs) is associated with insulin resistance, triglyceride-rich dyslipidemia, and fat redistribution. Atazanavir (ATV), a potent once-daily PI, has been recognized for its convenience to patients, and some studies describe improved lipid metabolism. However, its effects on insulin sensitivity have not been elucidated. We conducted this study to test the hypothesis that ATV improves insulin resistance and dyslipidemia. METHODS: We prospectively studied 9 HIV-infected men with dyslipidemia (median age, 53 years; baseline triglyceride level, >200 mg/dL) on stable PI-containing antiretroviral therapy who elected to change PI therapy to ritonavir-boosted ATV therapy, dose of 300/100 mg. We measured insulin resistance at baseline and after 12 weeks of therapy using a hyperinsulinemic euglycemic clamp (insulin dose, 200 mU/m minute). Fasting lipid profiles and body composition (whole-body dual energy x-ray absorptiometry) were also measured at baseline and after 12 weeks. RESULTS: All 9 patients completed the study and maintained undetectable viral loads (<50 copies/mL) and stable CD4 counts. After 12 weeks, insulin sensitivity significantly improved (+28%; P = 0.008) in all patients. Triglyceride levels also improved. CONCLUSIONS: Using the gold-standard euglycemic clamp, ritonavir-boosted ATV therapy improved PI-induced insulin resistance among dyslipidemic HIV-infected men on PI-based antiretroviral therapy. These findings were not attributable to a change in body weight and provide further evidence for ATV's unique metabolic profile among the PIs.  相似文献   
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Factors attracting and keeping nurses in home care   总被引:1,自引:0,他引:1  
  相似文献   
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The right atrium has a significantly higher capacitance than the left atrium, and this may affect the Doppler flow pattern across an atrial septal defect (ASD) in unilateral atrioventricular (AV) valve atresia. This Doppler flow pattern is often used to assess ASD adequacy in this setting. We studied the effect of atrial capacitance and ASD size on the trans-ASD Doppler flow pattern in an in vivo flow model of alternate left or right AV valve atresia (LAVVA and RAVVA). We assessed trans-ASD Doppler flow patterns using the max/min velocity ratio and mean interatrial pressure gradients (PGs). In both models, ASD flow rate correlated with mean trans-ASD PG, but for similar flow rates the slope was higher in the LAVVA model. In LAVVA, a persistent PG was consistently observed, with low max/min ratio (median, 1.46; range, 1.03-3.13), whereas in RAVVA, phasic flow was common (median, 8.0; range, 2.8-20). Because atrial capacitance affects mean PG and Doppler flow pattern across the ASD, we propose that the assessment of ASD adequacy in RAVVA should not rely on Doppler findings.  相似文献   
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Gastric duplication cysts are an extremely rare anomaly with few reported cases in association with accessory pancreatic tissue. Diagnosis can be challenging given a presentation of recurrent pancreatitis and resemblance to pancreatic pseudocysts. We report the case of a 6-year old boy with multiple episodes of pancreatitis who was discovered to have an accessory pancreatic lobe connected to a gastric duplication cyst, successfully treated with surgical excision.  相似文献   
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Introduction

The development of new surgical approaches for the management of congenital abdominal wall defects may be facilitated by using an animal model. However, because the anatomy of the neonatal abdominal wall has not been described, a suitable model is yet to be identified. We aimed to evaluate and define the neonatal abdominal wall musculature using ultrasound, to be used as a reference to identify an appropriate animal model for the neonatal abdominal wall in the future.

Methods

Infants with a postconceptual age of less than one month weighing between 2 and 3 kg were eligible. With ethical approval, ultrasonography of three abdominal wall locations bilaterally was performed. The depth of the skin to external oblique and the thickness of the three abdominal wall muscles, external oblique (EO), internal oblique (IO) and transversus abdominis (TA), were measured.

Results

Ten males and seven females were recruited with median postconceptual age of 36 weeks (IQR 36–38), median postnatal age of 8 days (IQR 3–30) and median weight of 2.35kg (IQR 2.26–2.56).The mean depth of EO from skin was 2.06 mm (± 0.44). The mean thicknesses of the muscles were: EO 1.02 mm (± 0.33), IO 1.16 mm (± 0.39) and TA 1.02 mm (± 0.37). There was no statistical difference between the thickness of EO, IO or TA (p = 0.43).

Conclusions

It is possible to consistently identify and measure the components of the neonatal abdominal wall musculature with ultrasonography. We hope this can aid in developing an appropriate animal model, with the ultimate aim of facilitating innovation in surgical management of neonatal abdominal wall pathology.

Levels of evidence

Study of Diagnostic test, Level IV.  相似文献   
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