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991.
BACKGROUND: Weight loss may be associated with unfavorable changes in body composition not compensated for by subsequent weight gain. OBJECTIVE: We examined the composition of weight change in relation to obesity, previous weight changes, weight-loss attempts, and physical activity. DESIGN: Part of the Danish MONICA (Monitoring Trends in Cardiovascular Disease) project, this was a longitudinal population study of changes in weight and body composition, with examinations in 1982-1983, 1987-1988, and 1993-1994. A total of 1236 men and 1200 women aged 35, 45, 55, or 65 y in 1987-1988 participated. Changes in fat and fat-free mass were measured by bioelectrical impedance. RESULTS: Before adjustment for age-related changes, fat-free mass made up 41% of weight lost and 24% of weight gained in men. In women, loss of fat-free mass (35%) was more than double that of gains (15%). After adjustment, the fractions of weight gained as fat-free mass were not significantly different from the fractions lost. These fractions were independent of age, obesity, and weight changes in the previous 5 y; successful weight-loss attempts; and physical activity. Independent of age and degree of obesity, weight changes were associated with greater changes in fat-free mass in men than in women. CONCLUSIONS: These data do not support the theory that weight loss or weight cycling may lead to an unfavorable body composition, nor do they provide a biological explanation for why long-term weight loss is often unsuccessful. However, the metabolic and health consequences of weight change may differ in men and women. 相似文献
992.
Relations between various measures of iodine intake and thyroid volume,thyroid nodularity,and serum thyroglobulin 总被引:5,自引:0,他引:5
Rasmussen LB Ovesen L Bülow I Jørgensen T Knudsen N Laurberg P Perrild H 《The American journal of clinical nutrition》2002,76(5):1069-1076
BACKGROUND: Iodine intake can be measured in various ways, and each method may have advantages and disadvantages. OBJECTIVE: We sought to investigate the potential associations of various measures of iodine intake with thyroid volume, prevalence of thyroid nodules, and serum thyroglobulin. We also sought to identify, if possible, groups at risk of thyroid disease because of their food choices. DESIGN: This cohort study included 4649 randomly selected subjects with mild-to-moderate iodine deficiency; the subjects lived in 2 cities in Denmark. Iodine intake was estimated by using a food-frequency questionnaire and by measuring iodine excretion in spot urine samples. Thyroid volume and nodularity were measured with ultrasonography. RESULTS: In multiple linear regression models, significant inverse relations were found between thyroid volume and estimated 24-h iodine excretion, iodine intake from diet plus supplements, iodine intake from diet/kg body wt, and milk intake (P = 0.001 for all), but not urinary iodine excretion measured as a concentration (P = 0.40). All measures of iodine intake were significantly related to serum thyroglobulin concentration (P 相似文献
993.
Breast-feeding protects against celiac disease 总被引:1,自引:0,他引:1
Ivarsson A Hernell O Stenlund H Persson LA 《The American journal of clinical nutrition》2002,75(5):914-921
BACKGROUND: Celiac disease, or permanent gluten-sensitive enteropathy, is an immunologic disease strictly dependent on exposure to wheat gluten or related proteins in rye and barley. OBJECTIVE: The aim of this study was to explore whether breast-feeding and the mode of introducing dietary gluten influence the risk of celiac disease in childhood. DESIGN: A population-based incident case-referent study of Swedish children, 627 cases with celiac disease and 1254 referents, was conducted; 78% of the matched sets were included in the final analyses. A questionnaire was used to assess patterns of food introduction to infants. Models were built, based on current epidemiologic and immunologic knowledge of celiac disease, to study the potential influence of dietary patterns on disease risk and were evaluated by conditional logistic regression in multivariate analyses. RESULTS: The risk of celiac disease was reduced in children aged <2 y if they were still being breast-fed when dietary gluten was introduced [adjusted odds ratio (OR): 0.59; 95% CI: 0.42, 0.83]. This effect was even more pronounced in infants who continued to be breast-fed after dietary gluten was introduced (OR: 0.36; 95% CI: 0.26, 0.51). The risk was greater when gluten was introduced in the diet in large amounts (OR: 1.5; 95% CI: 1.1, 2.1) than when introduced in small or medium amounts. In older children, these risk factors were of no or only minor importance. CONCLUSIONS: The gradual introduction of gluten-containing foods into the diet of infants while they are still being breast-fed reduces the risk of celiac disease in early childhood and probably also during the subsequent childhood period. 相似文献
994.
Male-biased sex ratios of fish embryos near a pulp mill: temporary recovery after a short-term shutdown 总被引:7,自引:0,他引:7
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In a previous study we showed that broods from the viviparous eelpout Zoarces viviparus were significantly male biased in 1998 in the vicinity of a large kraft pulp mill on the Swedish Baltic coast. One suggested hypothesis was that masculinizing compounds in the effluent were affecting gonadal differentiation of the embryos, resulting in skewed sex ratios. In this article, we present further evidence for a causal relationship between the exposure to the effluent and the male-biased sex ratios. Analyses of historical samples showed that the eelpout produced male-biased broods close to the mill in 1997 in addition to 1998. During 1999, the mill was shut down for 17 days, coinciding with the period when the gonads of the eelpout embryos differentiate. Subsequently, in the fall of 1999, the sex ratios were no longer male biased; however, the following year (2000), a significant male bias reappeared. Investigations at 13 sites for up to 4 years showed a relatively stable sex ratio around 50/50, with the exceptions by the mill and with few observations of deviating ratios at other sites. Several reports document endocrine disturbances in fish near pulp and paper mills, including the expression of male secondary sex characters in female fish. The repeatedly identified male bias at the investigated mill, the normalization after mill shutdown, and the reappearance the following year indicate that pulp mill effluents also can affect sex ratios of nearby fish. 相似文献
995.
Babiloni C Babiloni F Carducci F Cincotti F Rosciarelli F Arendt-Nielsen L Chen AC Rossini PM 《Human brain mapping》2002,15(2):112-123
The main aims of this study were 1) a fine spatial analysis of electroencephalographic (EEG) oscillations after galvanic painful stimulation (nonpainful stimulation as a reference) and 2) a comparative evaluation of phase- and nonphase-locked component of these EEG oscillations. Preliminary surface Laplacian transformation of EEG data (31 channels) reduced head volume conductor effects. EEG phase values were computed by FFT analysis and the statistical evaluation of these values was performed by Rayleigh test (P < 0.05). About 50% of the EEG single trials presented statistically the same FFT phase value of the evoked EEG oscillations (phase-locked single trials), indicating a preponderant phase-locked compared to nonphase-locked component. The remaining single trials showed random FFT phase values (nonphase-locked single trials), indicating a preponderant nonphase-locked compared to phase-locked component. Compared to nonpainful stimulation, painful stimulation increased phase-locked theta to gamma band responses in the contralateral hemisphere and decreased the phase-locked beta band response in the ipsilateral hemisphere. Furthermore, nonphase-locked alpha band response decreased in the ipsilateral fronto-central area. In conclusion, both decreased and increased EEG oscillatory responses to galvanic painful stimulation would occur in parallel in different cortical regions and in the phase- and nonphase-locked EEG data sets. This enriches the actual debate on the mapping of event-related oscillatory activity of human brain. 相似文献
996.
Cognitive functioning in Alzheimer's disease and vascular dementia: further evidence for similar patterns of deficits 总被引:2,自引:0,他引:2
Fahlander K Wahlin A Almkvist O Bäckman L 《Journal of clinical and experimental neuropsychology》2002,24(6):734-744
The purpose of the present study was to examine possible differences in patterns of cognitive performance between population-based samples of Alzheimer's disease (AD; n = 51) and vascular dementia (AD; n = 14) patients between 75 and 96 years of age. The two demented groups were comparable in age, years of education, gender distribution, and severity of dementia. The selection of cognitive tasks (letter and category fluency, Block design, Clock reading and setting, and episodic face recognition) was thought to address some of the inconsistencies in previous research. The main finding was that AD and AD patients were comparable on most tasks, although robust dementia-related deficiencies were found when comparing the results of the demented participants with those of the control participants. These findings suggest that AD and AD may affect several basic cognitive functions in an equal manner. 相似文献
997.
A method for characterising cell death in vitro by combining propidium iodide staining with immunohistochemistry 总被引:3,自引:0,他引:3
The fluorescent exclusion dye propidium iodide (PI) is widely used as a vital dye in tissue culture systems and labels the nucleus in dying cells which lack an intact plasma membrane. We have developed a method, which allows the preservation of the PI signal in paraformaldehyde-fixed tissue, enabling subsequent immunohistochemical characterisation of labelled cells. We have tested this method in a model of ischemia based on oxygen and glucose deprivation in organotypic hippocampal slice cultures, in combination with immunocytochemical detection of calpain-I mediated spectrin breakdown products (BDPs). Using confocal laser microscopy it was possible to correlate at the single cell level which cells were PI positive and which cells expressed BDPs. This method can also be used with other immunocytochemical markers to determine the phenotype of cells, which accumulate PI in vitro. By fixing tissue at different times after insults, it is possible to obtain a 'snapshot' of viability at any time during the experimental protocol and subsequently characterise those cells which had accumulated PI at the time of fixation. The technique may also prove useful in characterising cell death in other in vitro and in vivo systems. 相似文献
998.
Sarich TC Eriksson UG Mattsson C Wolzt M Frison L Fager G Gustafsson D 《Thrombosis and haemostasis》2002,87(2):300-305
Ximelagatran, an oral direct thrombin inhibitor, whose active form is melagatran, was studied using a model of thrombin generation in humans. Healthy male volunteers (18 per group) received ximelagatran (60 mg p.o.), dalteparin (120 IU/kg s.c.) or a control (water p.o.). Shed blood, collected after incision of the forearm with standardised bleeding time devices at pre-dose, and at 2, 4 and 10 h post-dosing, was analysed for markers of thrombin generation. Statistically significant reductions (p < 0.05) in levels of prothrombin fragment 1+2 (F1+2) and thrombin-antithrombin complex (TAT) in shed blood were detected at 2 and 4 h post-dosing in both the ximelagatran and dalteparin groups. Shed blood F1+2 and TAT levels had returned to pre-dose levels at 10 h post-dosing. Using a shed blood model, we demonstrate that the reversible thrombin inhibitor melagatran and, therefore, oral administration of ximelagatran, inhibits thrombin generation in humans after acute activation of coagulation. 相似文献
999.
As part of research into small group homes run by local authorities for those with severe mental illness the characteristics of the social environment was investigated. The ideal and real versions of the Community Oriented Program Environmental Scale (COPES) were administered to residents and staff of small group homes in a county in southern Sweden. Both these groups were also interviewed on their opinions as to the main characteristics that should exist in the social environment in small group homes. High levels of support, order and organization, and program clarity and a low level of anger and aggression distinguished the real social environment according to the residents. Differences between residents' and staff's perceptions were less pronounced than in most other studies, probably owing to a greater level of resident--staff interaction in the home-like milieu. In the interviews both the residents and staff emphasized the importance of social interaction as a major constituent in the social environment of small group homes. The COPES instrument appears to be valid for use in small group homes, although some concern can be raised about two of the subscales, Involvement and Practical Orientation. The social environment, as rated by the residents and staff, was similar to that recommended for psychotic patients and to that proposed as a suitable supportive profile together with low levels of staff control and anger and aggression. 相似文献
1000.
This study intended to determine the prevalence of posttraumatic stress disorder symptoms and to report subjective well-being, general distress, and social functioning among police officers 18 months after a rescue operation during a fire at a discotheque. Emotional responses, including self-reported reactions, recorded during and after the fire were analysed. Forty-one police officers participated in the study. They completed a questionnaire and a battery of self-report measures. Psychological distress was recorded using the PTSS-10, IES-R, and GHQ-28. The three scales had a high internal consistency. The police officers were not unaffected by their experiences, and a few officers were still under stress. One police officer had IES-R intrusion and an avoidance score greater than 20, suggesting a stress reaction of clinical significance. When compared with the PTSS-10 scale, two (5%) officers showed a high level of psychological distress. Measured with the GHQ-28, three officers (7%) still had a high level of psychological distress. On one of the four different subscales most of the officers show various degrees of reduced social functioning. Debriefing was carried out by the police department after the fire, and 75% thought debriefing was positive. Eighteen months after the disaster a few police officers are still under stress. 相似文献