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51.
Nosratollah Zarghami Mohammad Rohbani-Noubar Ali Khosrowbeygi 《Indian journal of clinical biochemistry : IJCB》2005,20(2):182-185
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
52.
Wen-dong WANG Nan-nan ZHANG Warren CHANDA Min LIU Syed Riaz ud DIN Yun-peng DIAO Lei LIU Jing CAO Xiao-li WANG Xing-yun LI An-hong NING Min HUANG Min-tao ZHONG 《Journal of Zhejiang University. Science. B》2018,(5)
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
53.
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
54.
Hamutoglu Nazire Burcin Gemikonakli Orhan Duman Ibrahim Kirksekiz Ali Kiyici Mubin 《Educational technology research and development : ETR & D》2020,68(1):437-462
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
55.
Mazen El-Masri Ali Tarhini 《Educational technology research and development : ETR & D》2017,65(3):743-763
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
56.
Ali Kemal Tekin 《Education 3-13》2016,44(3):353-366
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
57.
58.
Aisha Salim Ali Al-Harthi 《Journal of Further & Higher Education》2017,41(6):760-772
There is more need today for school leaders to be up-to-date with technology and its various uses in education. Enhancing self-efficacy in the use of technologyis an expected role of educational leadership preparation programmes. This study investigated technological self-efficacy of a group of educators in leadership positions while participating in a leadership preparation programme at Sultan Qaboos University in Oman. The findings show that these educators had high technological self-efficacy. There were also significant, positive relationships between technological self-efficacy variables, academic achievement and age. Age was negatively correlated with general learning self-efficacy and also with one indicator of academic achievement. In the qualitative analysis, the study used the framework of the Theory of Margin (TM) to identify the factors affecting technology self-efficacy. Results indicate that, while participants with a high power-load margin (PLM) reported a higher number of internal and external powers, those with a lower PLM reported a higher number of internal and external loads. 相似文献
59.
Nazar Ali Korejo Quan-wei Wei Atta Hussain Shah Fang-xiong Shi 《Journal of Zhejiang University. Science. B》2016,17(11):850-863
This study evaluated the effects of comorbid disorders of diabetes and hyperthyroidism in the adult male mice. In total, 32 ICR strain mice were equally distributed into four groups: control (C), diabetic (D), diabetic-plushyperthyroid (DH), and hyperthyroid (H). Mice allocated for diabetes received a single intraperitoneal injection of streptozotocin (STZ) at 200 mg/kg body weight. At the onset of diabetes, one group of mice was concomitantly injected levothyroxine (LT4; 0.3 mg/kg body weight) and the other set of animals received the same treatment independently on a daily basis. The body weight, as well as the testicular and epididymal weights, was reduced markedly in D and DH mice. Higher trends of blood glucose levels were seen in the DH group, in comparison to euthyroid diabetic mice. Thyroid hormones could exert a transient effect on blood glucose homeostasis by altering the serum blood glucose level in diabetic patients. Histomorphometric analysis showed increased luminal sizes of seminiferous tubules, along with decreased epithelial height and atrophic changes in germinal stem cells in the testis of DH and H mice. Caput epididymis of DH mice showed extensive compaction of principal cells, loss of stereocilia, lipid vacuolization, and inflammatory infiltrations; however, damaged tubular integrity, packed clear cells, exfoliated cells, and round spermatids were profoundly noticed in the cauda epididymis. Hyperthyroidism elevated the serum testosterone levels in H and DH mice and produced critical damages to the histoarchitecture of the epididymis. Collectively, this experiment endeavored to mimic the polyglandular autoimmune syndrome, which will be helpful to better understand the reasons for male infertility in diabetic-cum-hyperthyroid patients. 相似文献
60.
Ali Nawab 《Teacher Development》2017,21(1):142-159
In-service courses have been used as a common strategy to build the capacity of teachers to meet the constantly changing demands of modern schooling. But how the teachers implement the ideas and strategies acquired from such in-service training and what conditions influence the implementation process is the least examined area in Pakistan, especially in the rural context. Using a case study approach, the current study explored the possibilities and challenges of implementing strategies, learnt through in-service training, in a public school in rural Pakistan. It was found that in-service courses have a positive impact upon the attitude and practices of the trainee teacher. However, due to various structural and cultural barriers, the teacher is not able to implement many of the strategies and ideas in the school context. The hierarchical structure of schools, teachers’ workload, lack of resources and insufficient support from colleagues and management hinder the process of implementation. The study suggests that in-service training should provide the trainees with ideas and skills to cope with the structural and cultural challenges at school. Moreover, ongoing support and encouragement from colleagues, course facilitators and management is required to sustain the implementation of strategies learnt during training. 相似文献