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61.
The popularity of herbal products, especially plant food supplements (PFS) and herbal medicine is on the rise in Europe and other parts of the world, with increased use in the general population as well as among specific subgroups encompassing children, women or those suffering from diseases such as cancer. The aim of this paper is to examine the PFS market structures in European Community (EC) Member States as well as to examine issues addressing methodologies and consumption data relating to PFS use in Europe. A revision of recent reports on market data, trends and main distribution channels, in addition an example of the consumption of PFS in Spain, is presented. An overview of the methods and administration techniques used to assess individual food consumption as a starting point, including their uses and limitations, as well as some examples of studies that collect Food Supplement (FS) information, including herbal/botanical/plant-derived products are also discussed. Additionally, the intake estimation process of food nutrients is described and used to propose the PFS ingredients intake estimation process. Nationally representative PFS consumption data is scarce in Europe. The majority of studies have been conducted in Scandinavia and the UK. However the heterogeneity of definitions, study design and objectives make it difficult to compare results and extrapolate conclusions.  相似文献   
62.
Differences in cognitive ability and domain-specific expertise may help explain age differences in pilot performance. Pilots heard air-traffic controller messages and then executed them while "flying" in a simulator. Messages varied in length and speech rate. Age was associated with lower accuracy, but the expected Age x Message Difficulty interactions were not obtained. Expertise, as indexed by pilot ratings, was associated with higher accuracy; yet expertise did not reduce age differences in accuracy. The effect of age on communication task accuracy was largely explainable as an age-associated decrease in working memory span, which in turn was explainable as decreases in both speed and interference control. Results are discussed within frameworks of deliberate practice and cognitive mediation of age differences. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
63.
The structure of depressive symptom patterns was investigated in a community sample of 344 women between the ages of 51 and 92 who were administered the SCL-90—R Depression and Additional Symptoms Scales. Confirmatory factor analysis was used to test alternative measurement hypotheses implied by clinical formulations of depressive symptom patterns among elderly persons. The findings show support for the hypothesis that 2 somewhat different depressive syndromes, along with 4 more delimited forms of distress, underlie symptom-reporting patterns. Implications of these findings for future research on the relation between aging and depression are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
64.
The image reconstruction capacity of the actual foveal cone sampling mosaics of an adult monkey and human is investigated through computer simulations. A retinocortical mapping model in which positions are known and disorder is compensated (DC) has been implemented using classical Whittaker-Kotelnikov-Shannon (WKS) reconstruction theory and a two-dimensional hexagonal tessellation technique that maps the cone lattice onto a perfectly hexagonal grid. The DC model has been compared with a retinocortical mapping model in which cone positions are also known but position disorder is uncompensated (DU) in the reconstruction process. A control model has also been implemented using WKS reconstruction based on sampled data obtained with simulated perfectly hexagonal lattices whose Nyquist limits are equivalent to those of the human and monkey lattices. Quantitative comparisons of these models are based on the RMS error per pixel between the original and reconstructed images. Results of these simulations demonstrate a pronounced superiority of the DC over the DU model. The results of these simulations, which use “biologically correct” sampling lattices, document a potential image reconstruction advantage when foveal cone positions are known.  相似文献   
65.
OBJECTIVE: To compare the antihypertensive efficacy and tolerability of a new combination preparation of diltiazem (150 mg) and hydrochlorothiazide (12.5 mg) with the individual constituents in patients with mild/moderate hypertension. DESIGN: Multi-centre, double-blind, randomised parallel group study. PATIENTS: Seventy-one patients with essential hypertension were recruited to the study. TREATMENT: Following completion of the placebo run-in period 63 patients fulfilled the prerandomisation criteria and entered the 10 week treatment period. Patients were randomised to receive either the combination preparation (D 150 mg/H 12.5 mg), diltiazem (150 mg) or hydrochlorthiazide (12.5 mg). The dosage was increased in three patients who had not attained target blood pressure (BP) control after 6 weeks. OUTCOME MEASURES: Response to treatment assessed by change from baseline in clinic and 24 h ambulatory BP. RESULTS: The proportion of patients achieving target BP (a reduction in resting supine diastolic blood pressure (DBP) to below 90 mm Hg or a reduction of 10 mm Hg from baseline) was 80% in the combination group, 55% in the diltiazem group, and 38% in the hydrochlorothiazide group. The respective figures for reduction in supine DBP from baseline were 13.5 mm Hg, 11.2 mm Hg and 5.9 mm Hg. A similar treatment order appeared throughout each of the efficacy variables. BP control throughout the 24 h dosing interval was demonstrated by ambulatory BP monitoring. Each treatment was well tolerated. CONCLUSION: This study provides clear evidence of the efficacy of combination therapy with diltiazem and hydrochlorothiazide in the management of patients with hypertension.  相似文献   
66.
Argues that organization development is increasingly recognized as an appropriate function for the school psychology specialty as a whole. It is suggested, however, that prior to introducing organization development in a particular school district, several considerations are appropriate. These prerequisite considerations include (a) resources needed for organization-development programs, (b) school readiness criteria for organization-development programs, (c) interventions available for schools lacking readiness, and (d) factors unique to the individual school psychologist. Particular attention is given to a continuum of school practice ranging from provision of specific organization-development interventions through sustained organization-development programs. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
67.
68.
Manipulated the withdrawal symptoms experienced by 62 cigarette smokers during a 48-hr smoking abstinence period. Ss were randomly assigned to 1 of 4 expectancy manipulation groups (psychological complaints, somatic complaints, no complaints, and no-expectancy control), and withdrawal symptoms were measured during 48 hrs of ad libitum smoking and 48 hrs of abstinence. The expectancy manipulation consisted of placebo nicotine gum and specific instructions as to the type of withdrawal symptoms to expect during smoking abstinence. Ss instructed to expect no complaints during abstinence reported fewer somatic complaints and less mood disturbance than the no-expectancy controls. Ss instructed to expect somatic, but not psychological, complaints reported more numerous and severe somatic withdrawal symptoms than did Ss instructed not to expect such symptoms. Results suggest expectancy may play a role in nicotine withdrawal experiences. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
69.
Color image quantization by agglomerative clustering   总被引:6,自引:0,他引:6  
We present a simple and “well-behaved” agglomerative clustering approach to color image quantization, along with results of tests using synthesized and real-life images  相似文献   
70.
Although the adverse mental health consequences of caregiving for a relative with a progressive dementia are well documented, little is known about caregivers' adaptation after bereavement. This longitudinal study examined changes in 3 groups: continuing caregivers, who had been caregiving across a 4-yr period (n?=?98), bereaved caregivers, whose impaired relative died between Years 1 and 4 (n?=?49), and controls (n?=?107). Although a mean of 19.8 mo had elapsed since bereavement by Year 4, bereaved and continuing caregivers did not differ on syndromal depression or depressive symptoms; both groups were significantly more depressed than controls. Time since bereavement was unrelated to depression or social support. Those caregivers who ruminated more about caregiving after bereavement reported more depression, greater stress, and greater social isolation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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