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151.
Total energy expenditure of elite synchronized swimmers measured by the doubly labeled water method 总被引:2,自引:0,他引:2
To determine the daily energy requirement of elite synchronized swimmers during moderate-intensity training, the average
daily energy expenditure measured by the doubly labeled water method, was calculated for nine female Japanese national team
synchronized swimmers [four senior; mean (SD) 22.5 (1.0) years old, 52.2 (3.6) kg, and five junior; 17.6 (1.1) years old,
52.8 (2.3) kg]. Their total energy expenditure (TEE) was 11.5 (2.8) MJ · day−1 [2738 (672) kcal · day−1]. When compared with estimated energy requirements derived from “Recommended Dietary Allowances for the Japanese”, 12.1 (0.6) MJ · day−1 [2897 (139) kcal · day−1], there was no difference between mean actual and estimated energy requirements. However, there were considerable differences
observed on an individual basis. Their energy intake, estimated from 7- day self-reported dietary records, was 8.9 (1.7) MJ ·
day−1 [2128 (395) kcal · day−1], which was significantly lower than their TEE (P < 0.05). Resting energy expenditure (REE), as determined by indirect calorimetry, was 5.2 (0.3) MJ · day−1 [1247 (75) kcal · day−1]. Their physical activity level (TEE/REE) was 2.18 (0.43). These results demonstrate that the TEE values of elite female
synchronized swimmers are not dissimilar to those reported for athletes participating in other sports, especially competitive
swimmers during moderate-intensity training.
Accepted: 26 May 2000 相似文献
152.
The details of mechanical construction and electronic circuitry of a strain gauge system for continuously measuring food and water ingestion in laboratory rats are described. The system has been reliably tested over a number of years. It is eminently suitable for investigating daily rhythms in rat feeding and drinking behavior, where a large volume of data is collected over extended periods of time. 相似文献
153.
The fact that electrical stimulation of the lateral hypothalamus (LH) can be substituted for the delivery of a food pellet in typical schedule induced polydipsia was established and demonstrated the role of this part of the brain in the mediation of adjunctive behavior. The assumption that Δ9-tetrahydrocannabinol (Δ9-THC) and ethyl alcohol affect behavior because of a differential effect on the same LH mechanism was supported by the following evidence. Relatively small doses of Δ9-THC, 0.25, 0.375, and 0.50 mg/kg, enhanced adjunctive drinking; whereas, larger quantities of 0.625 and 0.75 mg/kg had no appreciable effects. The effect is somewhat specific, as it did not occur with strychnine sulfate, and rate dependent within limits as it was most pronounced in animals with low rates of responding or in animals when responding at a low rate. The effect of rate dependency was also apparent with fixed interval schedules of 2 and 4 min and a multiple schedule of a fixed interval and a signalled timed out period of nonreinforcement. Low rates of responding were enhanced by all doses of Δ9-THC, 1.0, 1.5, 2.0, 2,5, and 3.0 mg/kg, and there was an obvious dose related decrease in high rates. A similar effect was observed with low and high rates of electrical self-stimulation through implanted LH electrodes. The hypothesis that some drugs such as Δ9-THC and ethyl alcohol can enhance the positive feedback in an LH mediated motor control system by the facilitation of the same mechanism which initially generated the behavior was confirmed. Oral self administration of ethyl alcohol in a saccharin sweetened fluid enhanced recovered adjunctive drinking of the solution in quantities which should be sufficient to produce physical dependence if continued for relatively long periods. Recovered adjunctive drinking occurs in animals without food or water deprivation and it is an intense and persistent phenomenon. 相似文献
154.
Heat and water vapour transfer of protective clothing systems in a cold environment,measured with a newly developed sweating thermal manikin 总被引:1,自引:0,他引:1
Fukazawa T Lee G Matsuoka T Kano K Tochihara Y 《European journal of applied physiology》2004,92(6):645-648
A moveable sweating thermal manikin has recently been developed. Thermal and water-vapour resistances of three kinds of cold-protective clothing ensembles, laminated with polytetrafluoroethylene, polyurethane and without a laminate were measured, with the aid of the manikin in a cold environment of 5°C with a relative humidity of 70% and an air velocity of around 1.5 m s–1. Two sweating rates of 65 and 130 g m–2 h–1 were employed. Supplied heat fluxes in both of the sweat rates ranged from 350 W m–2 to 400 W m–2. To maintain a comfortable condition, the skin wettedness (w) (mean weighted value) had to be kept at 0.6. The measurements obtained from the manikin when testing the three ensembles were w=0.3 (approximately) for the low sweat rate and w0.6 for the high sweat rate, irrespective of the property differences among the ensembles. In addition, the condensation in the ensembles in comparison with those calculated from an analytical equation is discussed. Condensation mass fluxes in the ensembles obtained byexperiment and those from the calculation agreed sufficiently well. Thus, distribution of the condensation in the ensembles was estimated using the equation. 相似文献
155.
Autoradiographic localization of kappa opiate receptors in CNS taste and feeding areas 总被引:1,自引:0,他引:1
Recent evidence suggests that kappa opiate receptors may play a key role in the regulation of appetite. Such evidence implies that kappa receptors might be localized within specific brain areas known to regulate ingestive behaviors. On the basis of this implication we employed an in vitro film autoradiographic technique using 3H-ethylketocyclazozine as ligand to identify putative kappa receptors within CNS "taste" nuclei and surrounding areas. Coronal cryostat sections of rat brain were incubated with ligand in the presence of D-Ala2, D-Leu5-enkephalin (DADLE) and morphine, apposed to LKB Ultrofilm for 60 days, processed and kappa receptor densities evaluated with the aid of a hand held photometer and video image analyzer. Highest kappa receptor densities were found within various gustatory and feeding sites including the rostral pole of the nucleus of the solitary tract, parabrachial nuclei, ventral posterior and medial portions of the thalamus, medial hypothalamus, medial nuclei of the amygdala and bed nucleus of the stria terminalis. Various other midline and medial limbic areas also showed significant kappa densities. 相似文献
156.
Postoperative water and electrolyte changes in skeletal muscle: a clinical study with three different intravenous infusions 总被引:1,自引:0,他引:1
Twenty-seven patients admitted for cholecystectomy were matched for age and sex in three groups for different perioperative fluid therapies over a period of 3 days. Group I was given an acetated half-isotone "balanced" saline solution with the addition of 2.5% glucose, Group II an acetated Ringer solution and Group III an isotonic glucose solution. Percutaneous muscle biopsies were performed before and on the third day after surgery for the determination of water content and the concentration of sodium, potassium, magnesium and chloride in skeletal muscle. The cumulative balance of sodium and potassium was measured daily during the study. In all three groups a significant increase in the total muscle water content was demonstrated. The concentration of sodium and chloride in skeletal muscle increased significantly in Groups II and III, whereas the concentration of potassium decreased in all groups. The cumulative sodium balance was positive in Groups I and II; the potassium balance was negative in all groups. In conclusion, the patients given the balanced saline solution showed the least change in water content and electrolyte concentrations in skeletal muscle. 相似文献
157.
Opong-Mensah K Woller TW Obaseki AO Porter WR 《Journal of pharmaceutical and biomedical analysis》1984,2(3-4):381-394
Equations have been developed that relate the concentration (or a parameter directly proportional to concentration, such as optical absorbance) of a weakly ionizable solute in a water-immiscible phase, in equilibrium with an aqueous phase, to the pH of the aqueous phase, the partition coefficient of the unionized solute and the phase volume ratio. These relationships have been used in the design of experimental methods for determining partition coefficients, which require measurement of solute concentration in only one phase. Data obtained in this way permit ready recognition of deviations from assumptions made in the development of the model; these assumptions include insolubility of the ionized solute in the water-immiscible phase and lack of interaction between buffer components and solute. Conditions for optimal liquid—liquid extraction of weakly ionizable solutes are more easily recognized. With these techniques, the negative logarithm of the acid dissociation constant (pK′a) and the logarithm of the octanol—water partition coefficient (log P) have been measured for warfarin (pK′a = 5.15 ± 0.04; log P = 2.82 ± 0.06), strychnine (pK′a = 8.29 ± 0.02; log P = 2.23 ± 0.04), phenol (pK′a = 9.88 ± 0.02; log P = 1.75 ± 0.05), procaine (pK′a = 8.11 ± 0.04; log P = 1.10 ± 0.08), and ephedrine (pK′a = 9.92 ± 0.01; log P = 1.65 ± 0.04) at 21°C. 相似文献
158.
王慧 ' target='_blank'> 范尉尉 ' target='_blank'> 陈凤格 ' target='_blank'> 牛玉杰 ' target='_blank'> 《现代预防医学》2022,(23):4277-4282
目的 对石家庄市2014—2021年生活饮用水常规指标进行监测,分析水质及主要监测指标变化趋势。方法 收集整理2014—2021年石家庄市生活饮用水监测资料,分析生活饮用水合格率、主要监测指标合格率、主要监测指标变化趋势。 结果 2014—2021年石家庄市共监测水样10529份,总合格率为77.15%;地表水合格率(99.08 %)高于地下水(75.96 %)、城市水合格率(85.17 %)高于农村水(75.05%)、枯水期合格率(79.79%)高于丰水期(74.51%),完全处理水合格率(99.10%)高于仅消毒(86.29%)和未处理(70.70%)(P均<0.05)。2014—2021年石家庄市生活饮用水最低合格率为69.49%,最高合格率为82.28%,总合格率呈上升趋势(P<0.05)。主要指标耐热大肠菌群 、菌落总数、总硬度、硝酸盐、硫酸盐的合格率均呈上升趋势(P<0.05),菌落总数、硝酸盐、氟化物、总硬度、溶解性总固体、硫酸盐、氯化物的含量均呈下降趋势(P<0.05)。结论 石家庄市2014—2021年生活饮用水水质整体呈现优化趋势,微生物指标仍是影响水质的主要因素。 相似文献
159.
目的了解重庆市某三甲医院消毒供应中心(CSSD)纯化水处理系统的细菌水平、消毒方法及效果。方法运用无菌技术采集重庆市某三甲医院CSSD不同时期的纯化水进行细菌培养,根据细菌培养、余氯、硬度检测结果对纯化水处理系统采取一系列措施以改善水质,并对各项措施的实施效果进行评价。结果该院CSSD纯化水存在细菌总数超标的情况,分别经过调整加盐量、更换水处理机耗材、安装含氯消毒剂加药装置并在水处理机制水时将5%84消毒液持续低流量泵入纯化水储水罐后,细菌总数明显降低,纯化水水质达标。结论该院纯化水存在细菌污染现象,医院应加强管理,CSSD需按时维护水处理设备,定期监测水质。 相似文献
160.
Along with sanitation and hygiene, water is a well-known driver of child undernutrition. However, a more direct role of household (HH) water access in shaping dietary diversity remains unexplored. We assessed the association between HH water access and achievement of minimum dietary diversity (MDD) among young children. We utilized nationally-representative cross-sectional data from the 2015/16 Malawi Demographic and Health Survey, which included 4727 mother–child dyads, respectively, (26.8 ± 6.8 years, range 15–49 years) and (13.9 ± 4.9 months, range 6–23 months). HH water access was categorized as (1) basic or no access, (2) intermediate, or (3) optimal. MDD was defined as feeding a child, during the previous day, at least four of the food groups defined by the World Health Organization. Only 27.7% of the children achieved MDD standards; most of the children who achieved MDD were from HHs with optimal water access (58.4%, p < 0.001). However, only 5.9% of the mother–child dyads were from HHs with optimal water access. After adjusting for covariates, children from HHs with optimal water access had higher odds of achieving MDD than those from HHs with basic or no water access (aOR = 1.74, CI = 1.24–2.46). Our results highlight the need to incorporate water-based strategies into national nutritional policies to increase dietary diversity among Malawian infants and young children. 相似文献