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71.
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
72.
The optimization of cultural conditions for β-glucanase production byBacillus subtilis ZJF-1A5 was investigated in flask trials. Temperature had great effect on β-glucanase production which maximized at optimal
temperature of 37°C and decreased significantly when temperature was over 37°C. Charge quantity affected β-glucanase production
significantly. Adding oxygen vector N-dodecane or acetic ether benefited β-glucanase production, but it depended on the concentration
and charge quantity. The results of fractional factorial design showed that age and size of inoculum and shaking speed were
the key factors affecting β-glucanase production and the cultivation time span to reach the highest β-glucanase activity.
The optimal cultural conditions for β-glucanase production obtained with CCD were as follows: inoculum age and size (16 h,
3.82% (v/v)), shaking speed 210 r/min, charge quantity of 30 mL in 250 mL flask and initial pH 7.0, cultured at 37°C for 50
h. Repeated experimental results accorded with those predicted by a second-order polynomial model. The amount of β-glucanase,
α-amylase and neutral protease produced byB subtilis ZJF-1A5 was associated partially with cell growth. Those three enzymes' activities increased following the cell growth and
increased significantly when cells entered the stationary phase.
Project (No. B0608) supported by the National Natural Science Foundation of China and a grant (2001121B25) from Hangzhou Science
and Technology Development Project of Zhejiang Province, China 相似文献
73.
Amir Cohen-Shalev 《Interchange》1990,21(2):1-14
A long-time lover of music, I confess to having a bizarre penchant for trying to test my informally trained musical intelligence in situations which require quick recognition, be it a piece, a composer, a performer, or some such feature. In fact, this article originated with my failure to recognize a theretofore unfamiliar work and with the surprise I experienced upon learning it was Verdi's last opera,Falstaff, composed when he was nearly 80. For a listener familiar withLa Traviata orAida, it appeared quite strange and surprising. Moreover, as I found out later, the sense of puzzlement was not merely a matter of subjective impression but rather exemplified an overall stylistic departure in Verdi's late life work, its salient features being compression and urgency rather than spaciousness, flowing line, a pervasive use of biting irony compared to the straightforward lyricism of the earlier work, a retreat from psychological realism in favour of sketchy, abstract portrayals, an overall impatience with established operatic convention, and a symphonic rather than linear or melodic conception. Some of these characteristics have also been found in the late works of painters and sculptors (e.g., Arnheim, 1986; Clark, 1972; Munsterberg, 1983). Taken together these observations raised for me the issue of artistic change, an issue of considerable significance to the understanding of creative endeavour in general. 相似文献
74.
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
75.
Mahar Ali Nawaz Munir Muhammad Elawad Sami Gowen Simon Richard Hague Nigel Graham Meckenzi 《浙江大学学报(A卷英文版)》2004,5(10):1183-1190
Cells and cell-free solutions of the culture filtrate of the bacterial symbiont, Xenorhabdus nematophila taken from the entomopathogenic nematode Steinernema carpocapsae in aqueous broth suspensions were lethal to larvae of the diamondback moth Plutella xylostella. Their application on leaves of Chinese cabbage indicated that the cells can penetrate into the insects in the absence of
the nematode vector. Cell-free solutions containing metabolites were also proved as effective as bacterial cells suspension.
The application of aqueous suspensions of cells of X. nematophila or solutions containing its toxic metabolites to the leaves represents a possible new strategy for controlling insect pests
on foliage. 相似文献
76.
目的:探讨射击运动员目标取向、竞赛状态焦虑的特点及二者之间的关系.方法:采用射击运动员目标取向测验和竞赛状态焦虑问卷对国家射击队、辽宁射击队、北京市射击队36名射击运动员进行调查.结果:(1)射击运动员的任务取向显著高于自我取向.国际健将级运动员任务取向显著高于国家健将和国家一级运动员,而自我取向显著低于后两者;(2)射击运动员的状态自信心得分较高.国家一级运动员的认知状态焦虑显著高于国际健将级和国家健将级运动员;国际健将级运动员的躯体状态焦虑显著低于国家一级运动员;国际健将级运动员的状态自信心显著高于国家健将级和国家一级运动员;(3)自我取向高分组的运动员认知状态焦虑更高,状态自信心更低;任务取向高分组的运动员认知和躯体状态焦虑更低,状态自信心更高.(4)自我取向显著正向预测认知状态焦虑,解释率为31.3%;任务取向显著负向预测躯体状态焦虑,解释率为17%;自我取向显著负向预测状态自信心,解释率为27.3%,任务取向显著正向预测状态自信心,解释率为35.5%.结论:运动级别越高的运动员越倾向于任务取向,认知和躯体状态焦虑越低,状态自信心越高. 相似文献
77.
Tiwari AK Mahdi AA Zahra F Chandyan S Srivastava VK Negi MP 《Indian journal of clinical biochemistry : IJCB》2010,25(4):411-418
The present study was conducted to investigate the oxidant–antioxidant status in iron deficient pregnant anemic women. One
hundred thirty pregnant women with iron deficiency anemia (IDA) were divided into three groups, namely mild (50), moderate
(50) and severe (30) anemic along with pregnant healthy women as controls (50). The complete blood count, plasma lipid peroxidation
products, enzymatic and non-enzymatic antioxidants were measured according to respective protocols. The levels of complete
blood count, iron, ferritin along with antioxidant enzymes namely catalase, superoxide dismutase, glutathione peroxidase,
glutathione reductase and reduced glutathione were significantly reduced in all IDA groups. However, the level of oxidized
glutathione, lipid peroxides, protein carbonyls, conjugated dienes were found significantly increased in all anemic patients.
Antioxidant vitamins, namely C, E and A were also found significantly decreased in IDA patients. On the basis of our results,
it may be concluded that IDA tends to increase the pro-oxidant components, which may result in various complications including
peroxidation of vital body molecules resulting in increased risk for pregnant women as well as fetus. 相似文献
78.
79.
本文给出了一种有效的余弦调制滤波器组的设计方法。这种算法采用了内插法和迭代算法相结合设计原型滤波器,目标函数表示为滤波器系数的四次方,用迭代算法来优化滤波器的系数。这种方法使需要优化的参数大大减少。最后的实例仿真,验证了此算法的有效性。 相似文献
80.
Internationalization of higher education: Challenges, strategies, policies and programs 总被引:1,自引:0,他引:1
Akbar Zolfaghari Mohammad Shatar Sabran Ali Zolfaghari 《美中教育评论》2009,6(5):1-8,20
In today's changing world, the idea of internationalization of higher education especially in developing countries has been deduced from globalization of education process. The international aspect of higher education is becoming increasingly important, composite, and confusing. The higher education has an effect on the society through policy-making, funding, and planning. The purpose of this paper is to analyze the meaning, definition, importance, necessity, and pre-requisites of internationalization of higher education. This paper also studies the programs and strategies of internationalization of higher education. Key challenges for the future direction of internationalization are identified in this paper. 相似文献