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1.
In a nationwide survey the nutritional status was assessed of 539 apparently healthy, independently living elderly aged 65-79 years. Anthropometric data showed no energy deficits. The prevalence of anemia was 4 and 1% among men and women, respectively. Many elderly showed a low level of 25-hydroxyvitamin D in plasma (less than 31 nmol/L: men 35%; women 43%), indicating a marginal status. Although the prevalence of low blood levels of folate, pyridoxal-5'-phosphate, and total carotenoids was higher among the elderly than among younger adults, clear (clinical) signs of nutritional deficiencies were not observed. Prevalence of obesity (13%), hypercholesterolemia (38%), and hypertension (63%) was found to be high, the percentages being higher for women than for men. Several indicators of the nutritional status appeared to differ among age groups. It is concluded that few differences can be considered as being due to physiological aging, which finding should be reflected in reference values for elderly people.  相似文献   
2.
A number of novel pyridazinomorphinans have been synthesized by the inverse electron demand Diels-Alder reaction of various 3,6-disubstituted 1,2,4,5-tetrazines with enamines derived from dihydrocodeinone and with codeinone. Reduction of some of the pyridazinomorphinans did not furnish the expected pyrroloepoxymorphinans; in all cases investigated reductive cleavage of the epoxybridge was observed to yield dihydropyridazino- or pyrrolomorphinans. The structures of all new compounds were assigned by the spectral data, that of the cycloadduct of codeinone was additionally verified by X-ray crystallography. Compounds 5a, 8, 11a , and 16 have been evaluated for their affinity at μ and κ opioid receptors in radioligand binding assays. Their ability to inhibit [3H]DAMGO binding at μ and [3H]U 69.593 binding at κ receptors, respectively as compared to codeine has been found to be lower.  相似文献   
3.
STUDY OBJECTIVE--The aim was to investigate whether dietary factors cluster in a favourable or unfavourable way and to characterise the groups identified by lifestyle and sociodemographic variables. DESIGN AND SETTING--This cross sectional study was based on data of the 1987-1988 Dutch national food consumption survey (DNFCS), obtained from a panel by a stratified probability sample of the non-institutionalised Dutch population. PARTICIPANTS--3781 adults (1802 males and 1979 females) of the DNFCS, aged 19 to 85 years, were studied. MEASUREMENTS AND MAIN RESULTS--To estimate dietary intake two day food records were used. Lifestyle factors were collected by structured questionnaire and sociodemographic variables were available from panel information. Cluster analysis was used to classify subjects into groups based on similarities in dietary variables. Subsequently, these groups were characterised by sociodemographic and lifestyle factors as well as by the consumption of food groups. Eight clusters were found. In comparison with the guidelines, the dietary quality in four clusters was poor. The cluster with the poorest dietary intake (high intake of fat, cholesterol, and alcohol; low intake of dietary fibre) showed on average a high consumption of animal products (except milk), fats and oils, snacks, and alcoholic beverages, and a low consumption of fruit, potatoes, vegetables, and sugar rich products. Smoking, body mass index, dietary regimen on own initiative, hours of sleep, gender, age, socioeconomic status, and day of the week were found to discriminate among the clusters. CONCLUSIONS--Cluster analysis resulted in substantial differences in mean nutrient intake and seems useful for dietary risk group identification. Undesirable lifestyle habits were interrelated in some clusters, but an exclusive lifestyle for health risk has not been found.  相似文献   
4.
To obtain more insight into the effect of moderate alcohol intake on vitamin B-6 status indicators, we studied the associations of alcohol intake (unadjusted and adjusted for intake of vitamin B-6 and protein) with the erythrocyte aspartate aminotransferase activation coefficient (EAST-AC) and plasma pyridoxal 5'-phosphate (PLP) level. Data obtained from men (n = 224) and women (n = 217) aged 65-79 (nationwide sample in the Netherlands) were used for this purpose. Although alcohol intake (a maximum of 21% of the energy came from alcohol) tended to be positively associated with PLP, this association never reached statistical significance (p greater than or equal to 0.05). EAST-AC was inversely associated with alcohol intake, whether or not it was adjusted for vitamin B-6 and protein intake. Similar results were found for the total EAST activity (after adding PLP) or apoenzyme activity; the basal EAST activity (before adding PLP) or holoenzyme activity was not associated with the alcohol intake. These results indicate that caution is needed in the interpretation of the specificity of EAST-AC (i.e., the degree to which EAST-AC is unaffected by other factors) as an indicator of vitamin B-6 intake.  相似文献   
5.
Desflurane is a trigger of malignant hyperthermia in susceptible swine   总被引:4,自引:0,他引:4  
Desflurane (difluoromethyl 1-fluoro 2,2,2-trifluoroethyl ether: CF2-H-O-CFH-CF3) is a potent inhalation anesthetic agent being investigated for possible clinical use. The authors examined the effects of this agent on normal swine and those from a special breeding program that were considered purebred for susceptibility to malignant hyperthermia (MH). Animals were exposed to 1 or 2 MAC or both doses of desflurane and observed for changes in end-tidal CO2, arterial blood gases, lactate, catecholamines, core temperature, blood pressure, and heart rate. All normal swine tolerated exposure to desflurane without clinical signs of MH, but significant changes in heart rate and blood pressure were noted. In contrast, of six MH susceptible swine tested, two had unequivocal MH reactions to deflurane, defined by significant increases of end-tidal CO2 (greater than 50 mmHg), an increase in PaCO2 (greater than 70 mmHg), a decrease in blood pH (less than 7.30), an increase in blood lactate concentration, and an increase in core temperature. Two other susceptible swine showed equivocal signs of MH but not until desflurane had been administered for 40-60 min. Finally, two other susceptible swine showed no signs of MH after 60 min of exposure to 2 MAC desflurane. These latter four animals all developed episodes of MH immediately after intravenous succinylcholine (2 mg/kg). The increased PaCO2, blood lactate concentrations, and temperature, and the decrease in pH induced by desflurane, were successfully treated with dantrolene and supportive measures. All surviving animals were biopsied 1 to 2 weeks after the exposure to desflurane for in vitro contracture testing to confirm MH susceptibility.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Noninvasive imaging techniques might be of particular diagnostic value for studying and monitoring cutaneous inflammatory conditions such as contact dermatitis. We evaluate acute allergic contact dermatitis (AACD) by means of optical coherence tomography (OCT) and correlate the clinical grading of patch test reactions with the findings obtained from OCT. Twenty positive patch test reactions (+, n = 6; ++, n = 7; +++, n = 7) are investigated using a conventional OCT scanner. In comparison to the control sites, OCT of AACD showed pronounced skin folds, thickened and/or disrupted entrance signals, and a significant increase in epidermal thickness. Moreover, clearly demarcated signal-free cavities within the epidermis and considerable reduction of dermal reflectivity are demonstrated by OCT. Notably, the latter findings strongly correlate with the clinical patch test grading. OCT may be a useful tool for visualization of micromorphological features of AACD. However, before OCT can be employed as an objective parameter in grading severity of patch test reactions, larger studies are required that correlate clinical patch test readings and OCT findings with histopathology.  相似文献   
10.
Mouse models of atopic eczema critically evaluated   总被引:2,自引:0,他引:2  
Atopic eczema (AE) is a chronic relapsing inflammatory skin disorder with increasing prevalence in Western societies. Even though we have made considerable progress in understanding the cellular and molecular nature of cutaneous inflammation, the precise pathomechanisms of AE still remain elusive. Experimental animal models are indispensable tools to study the pathogenic mechanisms and to test novel therapeutic approaches in vivo. For AE a considerable number of mouse models have been proposed and have been used to study specific aspects of the disease, such as genetics, skin barrier defects, immune deviations, bacteria-host interactions or the role of cytokines or chemokines in the inflammatory process. While some models closely resemble human AE, others appear to reflect only specific aspects of the disease. Here we review the currently available mouse models of AE in light of the novel World Allergy Organization classification of eczematous skin diseases and evaluate them according to their clinical, histopathological and immunological findings. The pathogenetic analogies between mice and men will be discussed.  相似文献   
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