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21.
Gérald Vanzetto Marc Janier Daniel Fagret Luc Cinotti Xavier André-Fouet Michel Comet Jacques Machecourt 《European journal of nuclear medicine and molecular imaging》1997,24(2):170-178
The best test presently available to ascertain residual viability within an infarct-related area involves the use of fluorine-18
fluorodeoxyglucose (FDG) to detect the persistence of some cellular metabolism. Rest reinjection of thallium-201 is a less
accurate alternative but is easy to perform. Iodinated fatty acids, which are used with standard gamma cameras, are proposed
as markers of cellular metabolism. This study was performed to assess the value of 16-iodo-3-methyl-hexadecanoic acid (MIHA)
as a marker of the residual cellular metabolism by comparison with FDG in patients with a recent myocardial infarction, and
to evaluate its contribution compared with the201Tl stress-redistribution-reinjection technique. Stress-redistribution-reinjection201T1 imaging, rest MIHA imaging and glucoseloaded FDG imaging were performed in 22 patients with recent myocardial infarction.
Out of the 628 myocardial segments obtained from the left ventricular analysis, 400 were hypoperfused (relative uptake <0.75
of maximum uptake on stress201T1 imaging), 177 of which were severely hypoperfused (relative uptake <0.50). Receiver operating characteristic (ROC) curves
for predicting metabolic myocardial viability with FDG were derived from the results in respect of (a)201T1 activity during exercise, redistribution and reinjection and (b) MIHA up-take, using the two FDG thresholds most commonly
considered to define metabolic viability (0.50 and 0.60). Analysis of the 400 hypoperfused segments demonstrated that201T1 reinjection was the most accurate test in predicting the presence of myocardial viability (area under the ROI curves=0.85
and 0.86 at the 0.50 and 0.60 FDG thresholds, respectively;P<0.05 vs other tests). The global predictive values of MIHA and201T1 reinjection were, respectively, 0.87 and 0.89 at the 0.50 FDG threshold (NS), and 0.82 and 0.87 at the 0.60 FDG threshold
(NS). When only the 177 severely hypoperfused segments were considered,201T1 reinjection remained the most accurate test (accuracy 0.84 at the 0.50 FDG threshold and 0.82 at the 0.60 FDG threshold),
while the accuracy of MIHA decreased significantly (0.78 at the 0.50 FDG threshold and 0.73 at the 0.60 FDG threshold,P<0.05 vs201T1 reinjection). In all circumstances, MIHA was less specific than201T1 reinjection for the detection of metabolic viability. In conclusion, in patients with recent myocardial infarction, MIHA
accurately detects the persistence of metabolic viability, but is not superior to201T1. 相似文献
22.
23.
T. E. CEDERHOLM A. B. BERG E. K. JOHANSSON K. H. HELLSTRÖM J. E. W. PALMBLAD 《European journal of clinical investigation》1994,24(9):615-620
Abstract Essential fatty acid (FA) deficiency, which may accompany protein-energy malnutrition (PEM), has been associated with impaired inflammatory reactions. We evaluated this relationship by analysing FA profiles and delayed cutaneous hypersensitivity in 20 malnourished elderly non-cancer patients and in 20 age-matched control patients. As indicated by serum cholesterol and serum triglycerides, the lipid levels were decreased by about one-third in the subjects with PEM. In comparison with the controls, there was a reduction in the ω 3 FA (e.g. eicosapentanoate) in total serum lipids (mgl-1 ) and serum phospholipids (%) of 40% and 47%, respectively. Reductions in serum ω 6 FA (e.g. linoleate and arachidonate) levels corresponded to the drop in total FA concentrations (30%). The cutaneous hypersensitivity was impaired in 14 of the malnourished patients. The magnitude of the skin reaction was positively correlated ( P < 0·05) to the concentrations of eicosapentanoate in serum lipids and serum phospholipids, as well as to the linoleate concentration in total serum lipids. Six of the malnourished patients took part in a nutritional intervention programme for 3 months. In parallel with an improvement in the nutritional status there was a 35% increase ( P < 0·05) in the total ω 3 FA serum concentration. Negative skin tests became positive and the median skin induration enlarged threefold ( P < 0·05). Thus, deficiency of ω 3 FA might be one factor contributing to cutaneous anergy in elderly malnourished patients. 相似文献
24.
David M. Cockburn 《Clinical & experimental optometry》1987,70(5):156-165
The clinical characteristics of 100 consecutively presenting diabetic patients of an optometrist were investigated. This sample was drawn from 3798 patient first visits and represented 2.6% of the practice population sample. Diabetic retinopathy was present in 26% of the diabetic patients; this prevalence is similar to that found in diabetics examined in community based surveys. The ocular complications of diabetics observed in this study appeared to be similar to those of diabetics in the general community. The mean random blood glucose levels of the diabetics having retinopathy was not significantly different from those not having retinopathy. A first degree family history of diabetes was admitted by 46% of the diabetic subjects and was the most common associated clinical feature surveyed; a control group of non-diabetic subjects had a first degree family history of diabetes in 10% of cases. In seven patients, the diabetes was diagnosed as a result of signs detected at the optometric examination; these signs are listed. No newly diagnosed diabetic had diabetic retinopathy as a presenting sign. Ocular and systemic signs, other than diabetic retinopathy, were sought and a high prevalence of cardiovascular disease was detected in these diabetic patients. The vision of the diabetic patients was compared to that of 100 randomly selected age and sex matched controls; there was no significant difference in the visual acuity of the two groups. The implications of this finding are discussed. Guidelines for the detection and management of diabetic patients of optometrists are suggested. 相似文献
25.
E. V. Borisova D. Yu. Rusakov S. K. Sudakov 《Bulletin of experimental biology and medicine》1992,114(3):1328-1332
26.
D. Dickerson B. Adams G. Engelbrecht G. Boltman R. Hickman D. Kahn 《Transplant international》1992,5(Z1):S63-S64
The precise cause of allograft dysfunction after renal transplantation often cannot be established by non-invasive means. In clinical practice, radionuclide scans form an integral part of the clinician's armamentarium in the assessment of these patients [1, 2]. Unfortunately, in the clinical setting more than one pathological process may be responsible for the impaired function, making it difficult to correlate the scan appearances with the pathology. In this study in rats we compared the renal DTPA scan appearances of the various pathological processes which may cause renal allograft dysfunction in the immediate post-transplant period. 相似文献
27.
Chronic food restriction has been shown to enhance glucose metabolism in adipocytes from lean Zucker rats at 10, 26, and 52 weeks of age compared to ad libitum-fed lean rats. Only adipocytes from food restricted 10-week-old obese rats demonstrated this response. In this study, lean and obese rats were food restricted from 5 until 14 weeks of age to determine the age at which adipocytes from obese rats were no longer affected by this intervention. Effects of 1 week of refeeding were also determined. When the rats were killed, body weights were highest in control rats followed by restricted/refed and then restricted rats within each genotype. Epididymal pad weights of lean rats were resistant to dietary intervention, while those of obese-restricted and obese-restricted/refed rats weighed less than pads of obese-control rats. Retroperitoneal pad weight was lowered by food restriction in both genotypes; but only that of lean-restricted/refed rats totally recovered with refeeding. Adipocytes of lean-restricted rats had the highest conversion of glucose to CO2. Glyceride-glycerol production was higher in obese compared to lean rats, but restricted rats had elevated conversion of glucose to fatty acids. In general, these results indicate that by 14 weeks of age obese Zucker rats no longer respond to food restriction with an elevated rate of glucose metabolism in adipocytes. 相似文献
28.
I. Sioen † C. Matthys G. De Backer J. Van Camp† & S. De Henauw 《Journal of human nutrition and dietetics》2007,20(6):580-589
BACKGROUND: Regular seafood consumption is recommended in dietary guidelines. The aim of this study was to investigate the importance of seafood as a nutrient source in adolescents' diet and the extent to which seafood consumption can increase the intake of omega-3 polyunsaturated fatty acids and vitamin D. METHODS: Consumption data recorded during seven consecutive days for 341 adolescents selected in Ghent (Belgium) were used to estimate the intake of vitamin D, linoleic (LA), alpha-linolenic (LNA), arachidonic (AA), eicosapentaenoic (EPA), docosapentaenoic (DPA) and docosahexaenoic (DHA) acid. RESULTS: The adolescents consumed on average 3.21 microg/day vitamin D, 11.7 g/day LA and 1.4 g/day LNA. The mean intakes of AA, EPA, DPA and DHA were 83.2, 55.9, 18.4 and 111.4 mg/day respectively. The major source of vitamin D was fortified margarine. Fats and oils were the main sources for LA and LNA. The intake of AA was mainly contributed by meat, poultry and eggs. Fish and seafood contributed for 84.1%, 59.3% and 64.4% respectively for EPA, DPA and DHA. CONCLUSION: Flemish adolescents would benefit from increased seafood consumption, as this would lead to a higher intake of EPA and DHA as well as of vitamin D. Moreover, replacement of foods rich in saturated fat (SFA) by seafood products can help to reduce SFA intake. 相似文献
29.
穹隆-海马伞切断对大鼠脑内TrkA表达的影响 总被引:1,自引:0,他引:1
①目的 探讨穹隆 海马伞切断对大鼠脑内不同部位神经生长因子受体TrkA表达的影响及临床意义。②方法 成年健康雌性Wistar大鼠 10只 ,随机分为穹隆 海马伞切断模型组和假手术组。两组大鼠均常规取海马CA1区、皮质区、杏仁复合体区、基底前脑Meynert核等部位脑组织与假手术组比较TrkA阳性细胞表达情况。③结果 假手术组大脑各观察区有基础水平的TrkA表达。模型组大脑海马CA1区、大脑皮质区、杏仁复合体区以及Meynert核区TrkA阳性细胞数明显减少 (t=3.94 4~ 8.4 4 2 ,P <0 .0 5 )。 ④结论 穹隆 海马伞切断可致大鼠脑内多部位TrkA表达减少 ,其可能是导致认知和情绪损伤的原因之一。 相似文献
30.
J. A. Dunstan J. Roper L. Mitoulas† P. E. Hartmann† K. Simmer S. L. Prescott 《Clinical and experimental allergy》2004,34(8):1237-1242
BACKGROUND: Breast milk contains many immunomodulatory factors (soluble CD14 (sCD14), IgA and cytokines) with the potential to influence infant immune development. OBJECTIVE: To determine if changes in breast milk omega-3 polyunsaturated fatty acid (n-3 PUFA) composition as a result of maternal dietary fish oil supplementation during pregnancy can modify levels of these immunological parameters in breast milk. METHOD: In a randomized controlled trial, 83 atopic women received either 4 g fish oil capsules (containing 3.7 g n-3 PUFA) (n = 40) or 4 g olive oil capsules (n = 43) from 20 weeks gestation until delivery. Breast milk was collected 3 days post-partum and fatty acids were analysed by gas liquid chromatography and IgA, sCD14 and cytokines (IL-5, IL-6, IL-10, TNF-alpha and IFN-gamma) were quantitated by ELISA or time resolved fluorescence (TRF). RESULTS: Omega-3 docosahexaenoic acid (DHA; 22:6n-3) and eicosapentaenoic acid (EPA; 20:5n-3) levels were significantly higher (P < 0.001) in breast milk from women supplemented with fish oil (n = 33, DHA mean 1.15%, SD 0.47% and EPA mean 0.16%, SD 0.07%) than in samples from the control group (n = 40, DHA mean 0.50%, SD 0.17% and EPA mean 0.05%, SD 0.02%). Breast milk arachidonic acid (AA; 20:4n-6) levels were significantly lower (P = 0.045) in the fish oil group (mean 0.55%, SD 0.12%) compared with the control group (mean 0.61%, SD 0.14%). Breast milk IgA was positively correlated with DHA (P = 0.046) and 22:5n-3 (P = 0.003), but inversely correlated with linoleic acid (LA; 18:2n-6) (P=0.034). Levels of sCD14 were also positively correlated with 22:5n-3 (P=0.009). Cytokines involved in IgA synthesis (IL-10 and IL-6) were also significantly correlated with both IgA and n-3 PUFA levels, although there were no differences in the levels of breast milk IgA, sCD14 or cytokines between study groups. CONCLUSION: Supplementation with fish oil during pregnancy significantly alters early post-partum breast milk fatty acid composition. omega-3 PUFA levels were positively associated with IgA and sCD14 levels, suggesting a relationship between fatty acid status and mucosal immune function. 相似文献