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971.
Increased plasma concentrations of small LDL particles denote an atherogenic lipoprotein phenotype (ALP) that is correlated with increased circulating TAG and reduced HDL-cholesterol. Principal component analyses of subfraction concentrations have previously been used in the Swedish population-based Malm? Diet and Cancer (MDC) cohort to identify three independent components, one pattern representing the ALP. The aim of the present study was to examine the associations between macronutrient intakes and the principal component representing the ALP. We examined 4301 healthy subjects (46-68 years old, 60 % women) at baseline in the MDC cohort. Dietary data were collected using a modified diet history method. Plasma lipoprotein subfractions were measured using a high-resolution ion mobility method. The principal component corresponding to the ALP was significantly associated with a higher intake of disaccharides, and inversely related to protein and alcohol consumption (P < 0·001 for all). The present findings indicate that the ALP may be improved by a low intake of disaccharides, and moderate intakes of protein and alcohol.  相似文献   
972.
Background and objective: Long-term exposure to cadmium (Cd) causes renal dysfunction, but the change in renal function with exposure is unknown. We assessed the evolution of Cd-induced renal effects after a reduction in dietary exposure to Cd in rice.Methods: Four hundred twelve residents in previously Cd-polluted and nonpolluted areas were examined twice, in 1998 and in 2006. Changes in blood Cd, urinary Cd, and kidney function [N-acetyl-β-d-glucosaminidase (NAG), β2-microglobulin, and albumin in urine] were measured.Results: In the most polluted area, mean blood Cd was 8.9 μg/L and 3.3 μg/L in 1998 and in 2006, respectively, and urinary Cd was 11.6 and 9.0 μg/g creatinine. Urinary albumin in 1998 increased with urinary Cd, but no such exposure–response relation appeared for 2006 albumin versus urinary Cd 1998, indicating recovery. Other biomarkers of kidney function were also elevated in 1998. Partial recovery was observed for NAG among women and was suggested for β2-microglobulin among young individuals. The probability of having β2-microglobulin levels above the 95th percentile in 2006 was high in those with elevated β2-microglobulin in 1998 [odds ratio (OR) = 24.8; 95% confidence interval (CI): 11.2, 55.3] compared with albumin (OR = 3.0; 95% CI: 1.2, 7.5) and NAG (OR = 2.6; 95% CI: 1.6, 4.4).Conclusions: Results suggest that a Cd-mediated increase in urinary albumin excretion is reversible upon substantial reduction of exposure. For markers of tubular effects, we observed a tendency toward improvement but not complete recovery. Data from repeated observations suggest that β2-microglobulin may be more informative than NAG as an indicator for an individual’s future tubular function.  相似文献   
973.
Background/Objectives:Considering the importance of glucose as a brain substrate, the postprandial rate of glucose delivery to the blood could be expected to affect cognitive functions. The purpose was to evaluate to what extent the rate of glucose absorption affected measures of cognitive performance in the postprandial period. In addition, cognitive performance was evaluated in relation to individual glucoregulation.Subjects/Methods:A white wheat bread (WWB) enriched with guar gum (G-WWB) with the capacity to produce a low but sustained blood glucose net increment was developed. The G-WWB was evaluated in the postprandial period after breakfast with respect to effects on cognitive function (working memory and selective attention (SA)) in 40 healthy adults (49-71 years, body mass index 20-29?kg/m(2)), using a high glycaemic index WWB for comparison in a randomised crossover design.Results:The G-WWB improved outcome in the cognitive tests (SA test) in the later postprandial period (75-225?min) in comparison with the WWB (P<0.01). Subjects with better glucoregulation performed superior in cognitive tests compared with subjects with worse glucoregulation (P<0.05).Conclusions:Beneficial effects on cognitive performance were observed with the G-WWB in the late postprandial period. The positive effect is suggested to emanate from improved insulin sensitivity, possibly in a combination with an enhanced neural energy supply. The results highlight the importance of carbohydrate foods that induces a low but sustained blood glucose profile in enhancing postprandial cognitive functions.  相似文献   
974.
975.
Busulphan and cyclophosphamide (Bu/CP) are widely used in preparative regimens for bone marrow transplantation. Many studies have shown a wide variation in busulphan pharmacokinetics. Moreover, higher rates of liver toxicity were reported in Bu/CP protocols than in a total body irradiation (TBI)-containing regimen. In the present paper we investigated the effect of the time interval between the last dose of busulphan and the first dose of cyclophosphamide on the pharmacokinetics of CP and its cytotoxic metabolite 4-hydroperoxycyclophosphamide (4-OHCP). Thirty-six patients undergoing bone marrow transplantation (BMT) were included in the study. We also investigated the occurrence of veno-occlusive disease, mucositis and graft-versus-host disease. Ten patients conditioned with CP followed by TBI served as a control group (TBI). Twenty-six patients were conditioned with Bu/CP. The patients received Bu (1 mg/kg x 4 for 4 days), followed by CP (60 mg/kg for 2 days) administered as a 1-h infusion. Patients received their CP therapy either 7-15 h (group A, n = 12) or 24-50 h (group B, n = 14) after the last dose of Bu. None of the patients were given phenytoin or any other drug known to enhance CP metabolism. The administration of CP less than 24 h after the last dose of Bu resulted in: (1) a significantly (P = 0.003) lower clearance for cyclophosphamide was observed in group A (0.036 l/h/kg) compared to 0.055 and 0.055 l/h/kg, in the B and TBI groups, respectively; (2) significantly (P = 0.002) longer elimination half-life in group A (10.93 h) than in groups B and TBI (6.87 and 7.52 h, respectively); (3) significantly (P < 0.001) lower exposure to the cytotoxic metabolite (4-OHCP), expressed as the ratio AUC4-OHCP/AUCCP, in group A (0.0053) than that obtained in group B (0.013) and group TBI (0.012); (4) the patients in group A had a significantly (P < 0.05) higher incidence of VOD (seven of 12) than the other groups, B and TBI (2/14 and 1/10, respectively); and (5) mucositis was significantly higher in group A patients (8/12), being seen in only one patient in group B and none in the TBI group. The present study has shown that the interval between busulphan and cyclophosphamide administration can negatively affect the pharmacokinetics of cyclophosphamide and its cytotoxic metabolite. We conclude that the timing of CP administration must be considered in order to improve drug efficacy and reduce conditioning-related toxicity.  相似文献   
976.
In developing countries such as Ethiopia, where chronic gastritis and peptic-ulcer disease are the most common endoscopic findings, it is important to study the association between Helicobacter pylori infection and gastroduodenal diseases. Both invasive and non-invasive diagnostic methods were therefore used to investigate 300, consecutive, adult patients with dyspepsia, from the gastrointestinal clinic of Tikur Anbassa University Hospital, Addis Ababa. The apparent overall prevalence of H. pylori infection varied according to the detection method employed. Culture revealed H. pylori in only 69% of the patients but this pathogen appeared more common when rapid urease tests (71%), PCR-denaturating gradient gel electrophoresis (91%), histopathology (81%), silver staining (75%) or stool-antigen tests (81%) were employed. Antibodies to H. pylori were detected, both by enzyme immuno-assay (EIA) and immunoblotting, in approximately 80% of the patients, whether the antigens used were of a reference strain or from a local isolate of H. pylori. When some of the EIA-positive and EIA-negative sera were cross-absorbed with antigens of Campylobacter jejuni and re-tested by EIA, the H. pylori-positive sera remained positive and the negative sera remained negative. Dyspeptic patients in Ethiopia, like most of those previously observed elsewhere in Africa, are often infected with H. pylori. It is important that the management of these patients should not be hampered by the misinterpretation of the African epidemiology of this pathogen.  相似文献   
977.
978.
Sham feeding experiments were performed in 20 duodenal ulcer (DU) patients by using adequate sham feeding and modified sham feeding (the 'chew-and-spit' technique). A 15-min sham feeding induced a marked secretion of gastric acid but only an insignificant increase in total gastrin or in gastrin17 concentrations in plasma. Nor did prolonged sham feeding (30 min) with intragastric neutralization significantly increase the gastrin concentrations. We conclude that sham feeding in DU patients induces a release of recognized gastrin components in amounts that are barely detectable radioimmunologically. Therefore, the acid secretory effects of vagally released gastrins in DU patients remains to be established.  相似文献   
979.
Ten slightly obese middle-aged men were instructed to increase their energy intake 25% during a period of 1 week, which was preceded by a control period of seven days. Body weight increased by 0.67 kg (SD 0.60) indicating good compliance with the regimen. Transmembrane sodium fluxes were determined with the use of 22Na. The pre-diet erythrocyte sodium content was 9.7 mmol/L (SD 0.8) decreasing to 8.9 mmol/L (SD 1.1) (P less than 0.05) during overfeeding. The Na-efflux rate constant increased from 0.40 h-1 to 0.54 h-1 (P less than 0.05). Urinary excretion of catecholamines and concentrations of catecholamines and insulin in plasma and of thyroxine, triiodothyronine, and reverse T3 in serum did not change. Thus, overfeeding seems to enhance the total Na efflux in erythrocytes from slightly obese men. There were no measurable changes in thyroid hormone or catecholamine levels leaving the regulatory mechanisms unexplained.  相似文献   
980.
Prerequisites for lack of age differences in memory performance   总被引:1,自引:0,他引:1  
Free recall performance of young and old adults was examined in three memory tasks: acts carried out by the subjects (subject-performed tasks or SPTs), sentences with imagery instructions, and sentences. The subjects were presented with the same verbal information in all three tasks. No age differences were observed on free recall of SPTs, whereas typical aging effects were obtained on free recall of the other tasks. This way the data from a previous study of no age effects on SPT recall were replicated. A hypothesis about imagery as a critical factor for the lack of age differences on SPT recall gained no support. Two main concepts were proposed to account for the data: Compensation among the elderly by means of the multimodal and rich properties of SPTs, and a superior ability for a spontaneous recoding of verbal information among young adults. The results were also discussed in relation to a presumption of memory tasks as varying in attentional demands.  相似文献   
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