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51.
Ramírez-Tortosa C López-Pedrosa JM Suarez A Ros E Mataix J Gil A 《The British journal of nutrition》1999,82(1):31-39
The present study describes a clinical trial in which Spanish patients suffering from peripheral vascular disease (Fontaine stage II) were given specific lipid supplements. Designed as a longitudinal intervention study, patients were provided with olive oil for 3 months, followed by a 3 month wash-out period, then supplemented with a combination of fish oil and olive oil for the final 3 months. Changes in plasma and lipoprotein fatty acid composition and susceptibility of LDL to in vitro oxidation were examined. Furthermore, lipid-supplement-induced changes in LDL properties were measured as relative electrophoretic mobility and macrophage uptake. In addition, thirteen patients not provided with olive oil and fish oil were included as a control group and twenty healthy age-matched individuals were used as a reference group. A complete clinical study and a nutritional survey concerning food habits and lifestyle were performed every 3 months. Yao indices and claudicometry did not change significantly with dietary intervention although changes in plasma lipid composition suggested an improvement in the condition of the patients. The intake of the fish-oil supplement resulted in significantly increased plasma levels of eicosapentaenoic acid (20:5n-3) and docosahexaenoic acid (22:6n-3) in comparison with baseline concentrations, olive-oil and control groups. Fish-oil consumption significantly decreased plasma triacylglycerol levels compared with the olive-oil period, control and reference groups. The susceptibility of LDL to Cu-mediated oxidation was lower in the patients consuming olive oil and the fish-oil supplement than in the control group, and the uptake of LDL by macrophages was significantly lower in the group supplemented with fish oil. In conclusion, consumption of olive oil together with a dietary supplement of fish oil may be useful in the nutritional management of patients suffering from peripheral vascular disease in terms of increasing plasma n-3 long-chain polyunsaturated fatty acids and decreasing susceptibility of LDL to oxidation. 相似文献
52.
The routine use of a 64 kb/sec Numeris network requires that a compromise be reached between image quality and time required for image transfer. Our goal was to present our experience and describe our choices when reporting examinations for two geriatric hospitals located at a short distance from our radiology department. Different digitization parameters were tested (resolution, compression) for 10 plain films corresponding to the usual clinical situations: abdominal X ray, chest X ray, wrist, spine and pelvis X rays. A subjective analysis of the global quality and of the quality of a region of interest enlarged twelve times has been performed. After result analysis, our choices were: digitization using 75 or 150 DPI and systematic use of a reversible compression format. This system proved satisfactory for both clinicians and radiologists; since its implementation, 1,800 files have been reviewed. 相似文献
53.
54.
Alpha-lipoic acid prevents 3,4-methylenedioxy-methamphetamine (MDMA)-induced neurotoxicity 总被引:5,自引:0,他引:5
A single administration of 3,4-methylenedioxymethamphetamine (MDMA, 20 mg/kg, i.p.), induced significant hyperthermia in rats and reduced 5-hydroxytryptamine (5-HT) content and [3H]paroxetine-labeled 5-HT transporter density in the frontal cortex, striatum and hippocampus by 40-60% 1 week later. MDMA treatment also increased glial fibrillary acidic protein (GFAP) immunoreactivity in the hippocampus. Repeated administration of the metabolic antioxidant alpha-lipoic acid (100 mg/kg, i.p., b.i.d. for 2 consecutive days) 30 min prior to MDMA did not prevent the acute hyperthermia induced by the drug; however, it fully prevented the serotonergic deficits and the changes in the glial response induced by MDMA. These results further support the hypothesis that free radical formation is responsible for MDMA-induced neurotoxicity. 相似文献
55.
Ramírez-Ordóñez R Barreto-Estrada JL García-Arrarás JE 《Brain research. Developmental brain research》1999,114(1):27-36
Growth factors are known to be important agents in the differentiation and modulation of neuronal phenotypes. We have analyzed the effect of several growth factors on the modulation of morphological and biochemical properties of avian embryonic sympathetic neurons. The growth factors studied include: nerve growth factor (NGF), neurotrophin-3 (NT-3), brain derived neurotrophic factor (BDNF), ciliary neurotrophic factor (CNTF), basic fibroblast growth factor (bFGF) and transforming growth factor beta-1 (TGF-beta1). Morphological properties were analyzed by immunocytochemistry to neurofilament proteins and visualization of fibers after glyoxylic acid-induced fluorescence. Biochemical modulation was determined by radioimmunoanalysis for the peptides enkephalin (ENK), somatostatin (SS) and neuropeptide Y (NPY) and by HPLC-electrochemistry quantification of catecholamines. Similar to previous results using chromaffin cell cultures [R. Ramírez-Ordó?ez, J.E. García-Arrarás, Peptidergic, catecholaminergic and morphological properties of avian chromaffin cells are modulated distinctively by growth factors, Dev. Brain Res., 87 (1995) 160-171], we found a dissociation in the modulation of biochemical and morphological properties, however, the effect of specific factors differed between the chromaffin and sympathetic cultures. We have focused on NGF to analyze its effect on the sympathetic peptide phenotypes and its lack of an effect on the chromaffin cell peptide phenotypes. The results presented here, establish interesting differences between chromaffin cells and sympathetic neurons that are of importance to studies of cell lineage and differentiation. 相似文献
56.
Ramírez R Martín R Martín JJ Ramírez JR Paniagua R Santamaría L 《Journal of andrology》1999,20(6):702-712
To investigate 1) the correlation between the proliferative activity of epididymal epithelium plus myoid cells and the increase in the number of these cells and 2) the role of the basal epithelial cells in the renewal of epididymal epithelium, a quantitative evaluation of the proliferation of both epithelial cells and periductal myoid cells in the different epididymal regions (caput, corpus, and cauda) has been carried out during postnatal development of the rat by immunohistochemical evaluation of BrdU-labeling indices. These data were correlated with cell numbers and counted by the optical dissector method. The presence of bcl-2 protein was immunohistochemically detected and evaluated. No significant differences in BrdU indices were observed among epididymal regions in any stage studied. Cell proliferation decreased from the prepubertal period to adulthood in both epithelial and myoid cells in the three regions of the epididymis, suggesting a close relationship between epithelial and mesenchymal components. The numbers of both cell types were significantly higher in the caput than in the corpus and cauda in all stages studied, suggesting functional differences between regions. A negative linear correlation between proliferative activity and cell numbers was noted that might be related to regulation of the cell population size. Basal cells showed a lower proliferation rate than principal cells, but most of the immunoreactive bcl-2 protein, in pubertal and adult epididymides, was observed in basal cells. Therefore, these cells might comprise a low-proliferating and apoptosis-resistant population. 相似文献
57.
Maximiano Vásquez R Roca Suárez A Ramírez Chamorro F de Alba López JR Gordón Laporte R 《Actas urologicas espa?olas》1999,23(9):814-817
Presentation of one case of scrotal hernia in a man of 64 years old patient. Diagnosed by cistography and ultrasound and treated by herniorraphy and posterior transuretral litolaplaxy of a vesical litiasis and RTU of prostate. Postoperative urography showed normal vesical morphology. 相似文献
58.
OBJECTIVES: To develop a video assessment method for General Practitioners (GPs) by analysing issues of validity, reliability and feasibility of observation of videotaped regular consultations. DESIGN: In a cross-sectional study consultations of 93 GPs were video recorded in the practice during 1 week. The GPs registered consultation and patient data in a logbook; 16 consultations per GP were selected using preset criteria. The quality of communicative and medical performance of these consultations was assessed by GP observers with a validated instrument. The validity of the procedure was evaluated by checking the content of each GP's sample using specific sample criteria. Selection bias was estimated by multiple regression analysis, with sample characteristics as independent variables and scores on communication and medical performance as dependent variables. The influence of observation on GPs and patients was assessed by a questionnaire. Generalizability theory was used to estimate reliability. Feasibility was assessed by conducting a questionnaire, by keeping accounts, and by checking the technical quality of the videotaped consultations. SETTING: Universities of Nijmegen and Maastricht, The Netherlands. SUBJECTS: General Practitioners (GPs). RESULTS: The domain of general practice was well covered in the samples; content validity was satisfactory. With regard to the sample characteristics, only the total duration of consultations appeared to correlate significantly with both the score on communication and the score on medical performance. A majority (71%) of GPs reported not being influenced by the observation, except in the first cases, and recognizing their usual daily performance in the videotaped consultations. An acceptable level of reliability was reached after 2.5 hours of observation, i.e. 12 cases by a single observer. The method was well accepted by both GPs and patients. The costs were pound250 per GP. CONCLUSIONS: Video assessment of GPs in daily practice according to the procedures described is a valid and reliable method, one which is useful for education and quality improvement. There is a trade-off between feasibility on one hand and validity, reliability and credibility on the other hand. Compared to investments in observation methods in standardized settings, the costs of video observation of GPs' actual performance are acceptable. 相似文献
59.
P3 component of the endogenous cerebral evoked response is a sophisticated, objective and quantitative approach to assess higher functions of the brain. This test was employed using auditory 'odd ball' paradigm to assess cognitive functions in thirty non insulin dependent diabetic patients (NIDDM) aged 43.6 +/- 9 yrs with poor blood glucose control. (HbAlc. 9.9 +/- 1.0%). The peak latencies of N2, P3 components of event related evoked potentials obtained in these patients were compared with 30 age and sex matched non diabetic healthy controls. Latencies of these potentials were: N2 = 248.0 +/- 36.3, P3 = 391.6 +/- 49.9 msec in NIDDM as compared to 220.6 +/- 26.4, 326.2 +/- 26.8 msec in controls and were highly significant (P < 0.001). The duration of disease, blood glucose level or the physical parameters of height, weight and blood pressure did not show any correlation with N2 or P3 latencies or amplitude. These findings provide an electrophysiological evidence of delayed cognition in poorly controlled NIDDM cases. 相似文献
60.
The vasodilator effect of eriodictyol (5,7,3',4'-tetrahydroxyflavanone), isolated previously from the medicinal plant Satureja obovata Lag., was studied in rat thoracic aorta rings. Eriodictyol relaxed in a concentration-dependent manner the noradrenaline (10(-6) M) and KCl (80 mM) induced contractions. The relaxant effect was more potent in noradrenaline precontracted preparations (IC50 = 6.11 +/- 0.2 x 10(-5) M) than in those precontracted with KCl (IC50 = 2.96 +/- 0.1 x 10(-4) M). Eriodictyol produced weakly concentration-dependent inhibition of the phasic component induced by KCl and noradrenaline while the inhibition of the tonic phase of these contractions was more pronounced. These effects were endothelium independent. In addition, eriodictyol (10(-5) and 5 x 10(-5) M) inhibited CaCl2 cumulative concentration response curves. Eriodictyol weakly inhibited the release of calcium from the sarcoplasmic reticulum and its contribution to the relaxant effect seems to be slight. We have also observed the relaxant effect of eriodictyol on phorbol-12-myristate-13-acetate (PMA) (10(-7) M) induced contractions both in normal calcium (IC50 = 4.69 +/- 0.3 x 10(-5) M) and calcium-free medium (IC50 = 3.74 +/- 0.4 x 10(-5) M). Finally we studied the effects on protein kinase C (PKC) activity. This flavonoid did not show any activity. These results suggest that the vasodilator effect of eriodictyol in rat thoracic aorta could be partially related to the inhibition of calcium influx or other enzymatic protein subsequent to activation of PKC related to the activation of contractile proteins like myosin light chain kinase (MLCK). 相似文献