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61.
International Journal for Educational and Vocational Guidance - The present study discusses a pilot intervention for youth in a predominantly Latinx rural community in the U.S. The intervention...  相似文献   
62.
Of all the senses, that of taste is perhaps the hardest to define and quantify and elucidation of the underlying mechanisms is unrespondingly difficult. This article describes a conceptual model — at the molecular level — for the four basic taste modalities, using apparent specific volume as a fundamental parameter. It also considers possible practical applications.  相似文献   
63.
Pregnancy is associated with significant, but reversible changes in thyroid function studies, which are among the most profound seen as a result of a normal physiologic state. The present study was carried out to find out alterations in thyroid function tests in each trimester in normal pregnant women as compared to non-pregnant women in Tabriz-Iran. A case-control study designed with 229 normal pregnant women that randomly selected from the first (64 samples), the second (92 samples), and the third (73 samples) trimesters and 250 randomly selected non-pregnant healthy female controls. Age range in both groups was 16–40 years. Thyroid function tests carried out by measuring serum levels of thyroid stimulating hormone (TSH), free and total thyroxin (FT4, TT4), and free and total triiodothyronine (FT3, TT3) by commercially available radio immunoassay kits. We found that mean TT4 increased progressively during pregnancy. Our study showed increasing in serum levels of TT3 in the second trimester and then declining during the third trimester compared with non-pregnant women. We showed that FT4 strongly decreased during the third trimester. Free T3 showed declining in the second and third trimesters. Mean TSH did not show significant difference in each trimester compared with non-pregnant women. The thyroid function tests in pregnancy should be interpreted against gestational age-related reference intervals to avoid mis-interpretation of thyroid function during pregnancy.  相似文献   
64.
Dietary spice components ofCurcuma longa andAbroma augusta have been screened for their protective effect against reactive oxygen species induced lipid peroxidation. They have been found to be efficient antioxidant when administered in combination. The purpose of the study was to investigate the effect of oral administration (300mg/Kg) of the aqueous extract of turmeric whose active ingredient isCurcumin andAbromine powder as a hypoglycemic agent mixed with diet. The effect of this aqueous extract on blood glucose, lipid peroxidation (LPO) and the antioxidant defense system in rat tissues like liver, lung, kidney and brain was studied for 8 weeks in streptozotocin induced diabetic rats. The administration of an aqueous extract of turmeric and abromine powder resulted in a significant reduction in blood glucose and an increase in total haemoglobin. The aqueous extract also resulted in decreased free radical formation in the tissues studied. The decrease in thiobarbituric acid reactive substances (TBARS) and increase in reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) clearly showed the antioxidant property of the mixture. It is suggested that these changes initially counteract the oxidative stress in diabetes however, a gradual decrease in the antioxidative process may be one of the factors which results in chronic diabetes. These results indicate that the mixture of the two plants have shown antidiabetic activity and also reduced oxidative stress in diabetes. A combination ofAbroma augusta and Curcuma longa also restored the other general parameters in diabetic animals. The results were statistically analyzed and indicated that combination of herbal extracts showed better efficacy as compared to individual herbal plant extracts used.  相似文献   
65.
目的:探究桑螵蛸脂类提取物的成分及对铜绿假单胞菌的抗菌和抗生物膜作用。创新点:中国传统中药桑螵蛸一直广泛应用于肾病的治疗,在抗菌领域未见报道,本实验首次证明桑螵蛸脂类提取物对铜绿假单胞菌有明显的抗菌和抗生物膜作用。方法:采用气相色谱-质谱联用技术,测定桑螵蛸脂质提取物的化学成分及其相对比例。采用纸片扩散法和琼脂平板稀释法观察桑螵蛸脂类提取物对铜绿假单胞菌的抑菌效应并测定最小抑制浓度(MIC)。采用结晶紫染色法和扫描电镜(SEM)进行抑制生物被膜的试验。结论:桑螵蛸脂类提取物中含有16种化合物,最丰富的成分分别是倍半萜类化合物、单萜和微量芳香族化合物。桑螵蛸脂类提取物对铜绿假单胞菌的MIC为4 mg/ml,对铜绿假单胞菌生物被膜的抑制作用明显。  相似文献   
66.
We report physicochemical characteristics of various kinds of liquid milk commercially available in Pakistan in comparison with those of fresh natural milk from animals. Milk samples were collected from local markets at Peshawar, Pakistan,and analyzed for their physical features, including moisture, total solids, specific gravity, conductivity, viscosity and titratable acidity (lactic acid equivalent), and chemical components and macro-minerals, including total protein, casein, lactose, ash and minerals (Na, K and Mg). These items were compared with the physicochemical characteristics of the fresh natural milk samples from buffalo, cow and goat. The results were also compared with reported nutritional quality of milk from various countries and World Health Organization (WHO) standards. We found that all the physical features and chemical components of commercially available milk in Pakistan markets meet WHO's requirements, except for Na, K, Ca and Mg, which are below the standards.  相似文献   
67.
Educational technology research and development - Virtual learning environments (VLEs) are web-based software systems that enable students to interact with their teachers and classmates, access...  相似文献   
68.
This study examines the major factors that may hinder or enable the adoption of e-learning systems by university students in developing (Qatar) as well as developed (USA) countries. To this end, we used extended Unified Theory of Acceptance and Use of Technology 2 (UTAUT2) with Trust as an external variable. By means of an online survey, data were collected from 833 university students from a university in Qatar and another from USA. Structural equation modelling was employed as the main method of analysis in this study. The results show that performance expectancy, hedonic motivation, habit and trust are significant predictors of behavioural intention (BI) in both samples. However, contrary to our expectation, the relationship between price value and BI is insignificant. Our results also show that effort expectancy and social influence lead to an increase in students’ adoption of e-learning systems in developing countries but not in developed countries. Moreover, facilitating conditions increase e-learning adoption in developed countries which is not the case in developing countries. Overall, the proposed model achieves an acceptable fit and explains its variance for 68% of the Qatari sample and 63% of the USA sample. These results and their implications to both theory and practice are described.  相似文献   
69.
The purpose of this study was to discover Turkish parents’ perceptions of life context variables, including personal knowledge and skills and personal time and energy for involvement activities in their young children's education. The scales used in this study were based on parents’ self-report, and included: (1) Parental Perceptions of Personal Knowledge and Skills for Involvement Activities and (2) Parental Perceptions of Personal Time and Energy for Involvement Activities. Moreover, a demographic survey was developed and used as the second instrument in this study. The results suggested that parents as a group tend to have positive perceptions of life context variables for involvement in their young children's education and their income is the strongest predictor of these perceptions.  相似文献   
70.
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