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21.

Aim

The present study aimed to assess whether dietetic intervention helps patients on fluid‐only diets to meet their energy and protein requirements. This topic has not been previously investigated.

Methods

A quasi‐experimental study of 57 patients receiving fluid‐only diets was conducted at The Townsville Hospital. The fluid consumption of participants was observed over 24 hours and was used to calculate total energy and protein intakes. The percentage of protein and energy requirements met was compared between patients receiving dietetic intervention and patients who were not.

Results

Patients receiving dietetic interventions met a higher percentage of their energy requirements (75.88) than the control group (18.10) based on median intakes (P < 0.001). Patients receiving dietetic intervention also met a higher percentage of their protein requirements (75.99) than the control group (13.80) based on median intakes (P < 0.001). Stratification for age, body mass index (BMI) and fluid diet type showed no change in effect.

Conclusions

This study shows that dietetic intervention enabled patients on fluid‐only diets to meet up to 80% more of their energy requirements and up to 95% more of their protein requirements. These results were consistent across age, BMI and fluid diet type. The significance of these differences has resulted in a change of clinical practice at the study hospital. All patients on fluid‐only diets for three days or longer are now blanket referred for dietetic intervention.  相似文献   
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Summary Dual-energy X-ray absorptiometry (DEXA) has been used to assess and compare the composition of whole body and major body regions in 12 female (weight, 56.9 ± 6–2 kg; BMI, 17.25 kg m-2) and 16 male (weight, 73.1 ± 9–6 kg; BMI, 20.28 kg m-2) healthy subjects. Standard deviations (and % coefficients of variation) of the differences between repeated measurements of fat ranged from 0.11 kg (9.0%) for arms to 0.42 kg (30%) for whole body; for arm bone mineral, 0.01 kg (2.0%), and for fat-free soft tissue of the whole body, 0.42 kg (0.8%). Limb muscle mass was estimated using a new theoretical model of body composition, and the corresponding precision ranged from 015 kg (3.8%) to 0.27 kg (1.5%) for arms and total limb muscle mass, respectively. Proportions of each region consisting of fat were greater in females than in males (range, 20.31% vs. 16.18%), respectively, but the ratio of trunk to leg fat was lower (34:49% vs. 46:38%, respectively). Regional proportions of bone were similar between the sexes (all in the range 2.9–5.6%, for both females and males). Mean total limb muscle masses were 14.2 kg (arms, 2.8 kg; legs, 11.4 kg) for females and 22.2 kg (arms, 4.8 kg; legs, 17.4 kg) for males, which were 33.6% and 36.0% of fat-free mass, respectively. The correlation coefficients between limb muscle (DEXA) and other indices of muscle mass were: for DEXA vs. total body potassium, 0.90 (SEE 1.1kg muscle mass) to 0.94 (1.6 kg); and for DEXA vs. anthropometry, 0.43 (1.2 kg) to 0.85 (1.3 kg). Those for limb volume (DEXA) vs. anthropometric volume, 0.91 (0.78 1) to 0.94 (1.91 1). It is concluded that DEXA enables the valid and reproducible estimation of fat, fat-free soft tissue, bone, and limb muscle mass.  相似文献   
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To investigate the sequence of changes in regional myocardial perfusion which precedes stress-induced angina, we measured great cardiac vein flow (GCVF), draining the anterior left ventricle, during incremental atrial pacing in 10 patients with normal anterior perfusion (group I) and in 11 patients with ≥ 50% diameter stenosis of the left main or proximal left anterior descending coronary artery (group II). Pacing produced angina in 11 of 11 and regional lactate production in 9 of 11 group II patients. Both groups had comparable resting GCVF (group I = 62 ± 7 ml/min vs group II = 76 ± 9 ml/min; p = NS) and both exhibited progressive increases in GCVF with pacing. However, the entire flow-demand relationship was displaced downward in group II, as evidenced by a reduction in the percent increase in GCVF both following the first 20-beat pacing increment (group I = 46 ± 6% vs group II = 16 ± 4%; p < 0.001) and at angina (group I = 113 ± 16% vs group II = 44 ± 9%; p < 0.001). The first 20-beat pacing increment increased the heart rate to only 77 ± 2 bpm in group II whereas angina and ECG changes did not occur until a pacing rate of 117 ± 6 bpm. These data indicate that regional flow abnormalities precede the onset of pacing-induced angina in patients with coronary disease (CAD) and that these flow abnormalities frequently are detectable at heart rates substantially below the anginal threshold.  相似文献   
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Stenosis at the origin of the left internal mammary artery graft is rare. We present a case with a suspected stenosis involving the origin of the left internal mammary artery that conventional angiography failed to demonstrate convincingly. Intravascular ultrasound illustrated a severe stenosis and the patient underwent successful stenting of the left internal mammary artery origin. The intravascular ultrasound finding of a dissection flap, just distal to the left internal mammary artery origin, suggests that local trauma to the vessel from prior catheterization procedures may have been responsible for the progressive narrowing at the left internal mammary artery ostium.  相似文献   
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Stent thrombosis (ST) after percutaneous coronary intervention has been the focus of intense interest because of its attendant morbidity and mortality. There is controversy about several facets of the problem. These include the frequency of ST with drug-eluting stents (DES) versus bare-metal stents (BMS), the timing of the event, clinical consequences, risk factors, adjunctive therapy, and new preventive approaches. Information has accrued rapidly from several sources, including randomized controlled clinical trials of DES versus BMS in carefully selected subsets of patients and registry experiences in larger patient groups, which provide a more universal real-world picture. The results from these different data sets are not completely concordant. However, several general conclusions can be made: 1) ST is an infrequent but very severe complication of both BMS and DES; 2) at the present time, during 4 years of follow-up from randomized controlled trials that compared DES and BMS, there is no apparent difference in overall ST frequency, although the time course for occurrence appears to differ, with a relative numeric excess of ST late after DES implant; 3) despite this relative imbalance, no differences in the end points of death or death and infarction between DES and BMS are observed; 4) longer-term follow-up of these patients as well as larger angiographic and clinical subsets of patients who receive this technology outside of randomized trials are required to fully study this issue; and 5) advances in stent platforms for drug elution as well as adjunctive pharmacologic therapy are being evaluated to enhance long-term safety.  相似文献   
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BACKGROUND: Electron beam tomography (EBT) is a noninvasive technique that allows the study of the entire coronary artery tree during a brief imaging session without the injection of any contrast media. Atherosclerosis is identified vicariously through the visualization of coronary calcific deposits. Quantitative assessments of calcium burden, such as calcium volume scores, have been shown to be a useful means to assess treatment-related changes in the extent of atherosclerotic plaques. Historically, the elderly female population has received less medical recognition regarding the risk and severity of coronary heart disease (CHD). METHODS: In the BELLES (Beyond Endorsed Lipid Lowering with EBT Scanning) trial, the presence of asymptomatic CHD in 600 postmenopausal women will be assessed by EBT. In this 1-year, multicenter, randomized, double-blind, parallel-group study, aggressive lipid-lowering treatment will be compared with moderate lipid-lowering treatment in postmenopausal women with hypercholesterolemia. The hypothesis we will test is that aggressive lipid-lowering therapy with 80 mg/d atorvastatin can produce greater reductions in atherosclerotic plaque burden as assessed by volumetric calcium scores than a moderate treatment with 40 mg/d pravastatin. The primary outcome measure will be the percent change from baseline in total CVS determined by EBT at 12 months. CONCLUSIONS: The results of the BELLES trial will help assess the actual incidence of CHD in postmenopausal women and the relative ability of two different lipid-lowering therapies to halt its progression.  相似文献   
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