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排序方式: 共有770条查询结果,搜索用时 31 毫秒
31.
Mohammed I. A. Ibrahim Musa Zakariah Reneilwe A. Molele Mohamed A. A. Mahdy June H. Williams Christo J. Botha 《Microscopy research and technique》2022,85(3):1160-1170
The testicular excurrent duct system undergoes several physiological and morphological changes during the reproductive stage or breeding season in mammals, birds, and reptiles. Studies on normal age-related histomorphological changes in the excurrent duct system of Japanese quails (Coturnix japonica) remain unreported, despite the extensive use of this bird as an avian model in research studies. The current study investigated the histological, ultrastructural, and histometric changes in the testicular excurrent duct system of the Japanese quail during three reproductive stages, namely prepubertal, pubertal, and adult. Simple squamous to low cuboidal cells formed the epithelia of the rete testis in prepubertal and pubertal birds, while in adult birds the lining was low cuboidal to cuboidal. In pubertal and adult birds, the nonciliated Type I epithelial cells of the proximal efferent duct displayed a subapical endocytotic apparatus comprising coated pits, coated apical tubules, and endosomes. There was a significant increase (p ≤ .001) in epithelial heights of all ducts of the excurrent duct system in the mature, sexually active, adult birds when compared to the other age groups. The luminal and tubular diameters, and the cross-sectional areas of efferent ducts and the epididymal duct unit increased significantly (p ≤ .001) with age. It is concluded that the morphology and morphometry of the excurrent ducts of the testis of the Japanese quail change as birds mature. 相似文献
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The remote West Australian town of Broome has a unique photography heritage that sheds new light on the complexities of photography and intercultural relations. During the early twentieth century thriving Japanese communities were established in this region around the lucrative pearling industry. These Japanese communities also helped to develop a fascinating photography culture in Broome. Photography was not simply a business opportunity for the Japanese or a means of documenting people and events; it was a medium through which hierarchised social relations were produced, redefined, and challenged. This article examines photographs by these Japanese residents as an important site of cross-cultural communication and interpretation. These photographs of Anglo-Australian, Japanese, and Aboriginal residents of Broome enrich the study of cross-cultural photographic encounters, and emphasise the dynamic and dispersed qualities of Australian photographic practice and history. Here national histories of photography are usefully conceptualised as the products of imbricated social, economic, and cultural relations that operate across regional, national, and international realms. 相似文献
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日本建筑在当今世界建筑中独具一格,是东方建筑的典型代表。在不同历史阶段日本在在对待外来建筑文化上,是基于一定的模式进行吸收和采纳,并与自身本土民族性的建筑文化发生交织与碰撞,使建筑跳脱出单一的仿造和复制,而是发生质变产生全新的内涵。日本建筑得以重生,在于建筑师找到了民族性与外来文化共生的发展途径,大胆创新,形成富有意蕴的新建筑。文章纵观日本建筑史,结合建筑实例进行分析,对中国现代建筑文化如何把握有很好的借鉴意义。 相似文献
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Inga Miina Elise Sipeniece Magdalena Rudziska Anna Grygier Monika Radzimirska‐Graczyk Edte Kaufmane Dalija Seglia Gunrs Lcis Pawe Grna 《European Journal of Lipid Science and Technology》2020,122(4)
Tocopherols, phytosterols, carotenoids, and squalene are present in mature seeds of Japanese quince. Yet, little is known about the relationship between these compounds and oil yield during fruit and seed development. The profile change of lipophilic compounds during fruit and seed development in Japanese quince cultivars “Darius,” “Rondo,” and “Rasa” is investigated. It is shown here that during fruit and seed development, there is a significant reduction, three‐ to over tenfold, in the concentration of minor bioactive compounds in seed oil. It is recorded that delay between synthesis of tocopherols and oil in Japanese quince seeds during the fruit development results in a logarithmic relationship between the oil content and tocopherols concentration in the seed oil (R2 = 0.980). Similar trends are observed between oil yield and phytosterols, and carotenoids (R2 = 0.927 and R2 = 0.959, respectively). The profile of fatty acids during the development of the seeds significantly is changed. The reduction of linoleic, palmitic, and gondoic acids levels and increment of oleic acid is noted. The oil content, profile of fatty acids, and concentration of bioactive compounds in all three genotypes of Japanese quince do not change significantly statistically during the last month of fruit development. Practical Applications: Some fruits are harvested at different degrees of maturity mainly due to a logistic issue and uneven ripening of fruits, which affects the chemical composition of whole fruit including seeds. Therefore, it would be good to know how the chemical composition is changing in plant material during development especially in the last month before harvest. Production of Japanese quince continues to rise year to year and with it the volume of generated by‐products such as seeds. This study demonstrates how it changes the oil content, profile of fatty acid, and concentration of tocopherols, squalene, phytosterols, and carotenoids in the seeds and seed oil of three Japanese quince cultivars “Rondo,” “Darius,” and “Rasa” during plant development. The provided information can be very useful for the manufactories oriented on the processing of by‐products, mainly seeds, generated by other branches of industry, for instance, fruit‐processing. 相似文献
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目的研究流行性乙型脑炎病毒在二倍体(2BS)细胞上的传代适应性,确定在2BS细胞上培养乙脑病毒的条件和方法。方法通过病毒毒力和免疫原性检测,观察在不同培养条件下乙脑病毒在2BS细胞上的增殖情况。结果pH值在7·4~7·6之间、人血白蛋白含量为0·2%、病毒稀释度为1:1000时,病毒维持液培养的病毒滴度最高。在2BS细胞上传50代的病毒滴度均在7·0logLD50以上,且差异无显著意义。连续传代后病毒的免疫原性下降。结论建议用于建立病毒种子库的流行性乙型脑炎病毒,在2BS细胞上传代不应超过3代。 相似文献
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通过对中国明清家具风格及艺术成就的讨论 ,对比日本家具及室内设计风格的发展 ,提出中国当代家具的设计应在研究学习传统做法的基础上开拓创新 ,要从造型手法和艺术神韵中提取明清家具的精髓 ,从而推进我国当代家具设计的发展 相似文献
40.
质朴自然的石景是日式庭园的一个显著特征,其变迁贯穿了整个庭园历史的发展过程.在和中国源远流长的文化交流中,日式庭园不断将中国传统文化的精髓根植其中,对其石景的发展产生了较大影响.在搜集中日文化交流及日式庭园和庭园用石相关资料的基础上,选择了27个具有代表性的庭园案例进行了用石状况调查,结合调查结果总结了庭园用石形态的发展变化状况,并对中国传统文化对其影响过程与模式进行了探讨,以更好地研究中日传统园林文化之精髓. 相似文献