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Structure of the nucleoli in domestic cattle spermatocytes  [cached]
Katarzyna Andraszek,El?bieta Smalec
Folia Histochemica et Cytobiologica , 2012, DOI: 10.5603/15543
Abstract: The work was aimed at determining the number and morphology of nucleoli in the prophase of the first meiotic division in domestic cattle males. The use of AgNO3 staining, commonly applied in cytogenetics for the identification of nucleolar organiser regions, made it possible to identify nucleoli in first-order spermatocytes. One nucleolus was identified in each analysed cell. Considerable morphological differentiation of the nucleoli during the prophase of the first meiotic division, particularly in leptotene, unobserved in other farm animal species, was noticed. Dark-hued grain-like structures were found within the disintegrating nucleoli, corresponding approximately or exactly to the number of the nucleolar organiser regions in the domestic cattle karyotype. Dark areas were identified in the selected prometaphase chromosomes. Their number corresponded with the number of active NORs defined in the domestic cattle karyotype.
冰核细菌对仁用杏胚珠超微结构的影响  [PDF]
彭伟秀,杨建民,张芹,孟庆瑞
园艺学报 , 2004,
Abstract: 应用透射电镜对两个仁用杏品种‘白玉扁’和‘一窝蜂’接种冰核细菌并低温处理后的胚珠超微结构进行了观察,发现冰核细菌对胚珠的超微结构有一定影响:(1)使珠心细胞发生严重的质壁分离,细胞质中存在大量泡状结构,线粒体的内部结构完全被破坏,呈透明状,而且有些珠心细胞中形成同心圆状的多膜内含物;(2)使胚囊中卵细胞的细胞核外膜膨胀,甚至核膜局部解体,细胞质中细胞器减少。这些变化致使胚珠发育不正常,影响受精而导致减产或绝收。接种冰核细菌并低温处理比单纯低温处理对胚珠超微结构的破坏程度重。
冰核细菌对仁用杏花粉超微结构的影响  [PDF]
彭伟秀,杨建民,张芹,孟庆瑞,李绍华,孙福在,赵廷昌
园艺学报 , 2001,
Abstract: 应用透射电镜对几个仁用杏品种接种冰核细菌并低温处理后的花粉超微结构进行观察,发现冰核细菌对花粉的超微结构有很大影响:(1)使花粉壁的覆盖层在某些区域解体消失或整个花粉外壁缺失;(2)使花粉中的细胞器受到破坏,包括线粒体被膜不完整,嵴呈囊泡状;内质网呈同心圆卷绕或折叠状排列包围部分细胞质而形成膜内含物;核糖体数量明显减少等。因为花粉中细胞器的破坏,花粉细胞内部形成一些空腔,花粉失去生活力。接种冰核细菌并低温处理比单纯低温处理对花粉超微结构的破坏程度加重。
Are nucleoli participating in programmed cell death
Karel Smetana
Journal of Applied Biomedicine , 2003,
Abstract: Despite numerous publications on nucleoli, their participation in terminal maturation andprogrammed cell death have not been studied extensively. On the other hand, some observationsclearly indicate that terminal maturation and programmed cell death are accompanied by markednucleolar changes which reflect the cessation of nucleolar biosynthetic activities. In addition,nucleolar changes in the course of terminal maturation may precede programmed cell death.
Number of nucleoli in diploids and polyploids of the genus Achillea L.
Janina D?browska
Acta Societatis Botanicorum Poloniae , 1989, DOI: 10.5586/asbp.1989.041
Abstract: Nucleoli were counted in 9228 interphase nuclei of the apical root meristem of 40 Achillea L. taxa (di-, tetra-. hexa- and octoploids). It was established that the distribution of nucleoli number in an interphase nucleus can be used as a rough practical indicator to distinguish between diploids and polyploids. The highest number of nucleoli (12) was found in an octoploid Achillea pannonica, but only in a small percentage of the nuclei (0.3% out of 283 nuclei).
Midkine translocated to nucleoli and involved in carcinogenesis  [cached]
Li-Cheng Dai
World Journal of Gastroenterology , 2009,
Abstract: Midkine (MK) is a heparin-binding growth factor with its gene first identified in embryonal carcinoma cells at early stages of retinoic acid-induced differentiation. MK is frequently and highly expressed in a variety of human carcinomas. Furthermore, the blood MK level is frequently elevated with advance of human carcinomas, decreased after surgical removal of the tumors. Thus, it is expected to become a promising marker for evaluating the progress of carcinomas. There is mounting evidence that MK plays a significant role in carcinogenesis-related activities, such as proliferation, migration, anti-apoptosis, mitogenesis, transforming, and angiogenesis. In addition, siRNA and anti-sense oligonucleotides for MK have yielded great effects in anti-tumor activities. Therefore, MK appears to be a potential candidate molecular target of therapy for human carcinomas. In this paper, we review MK targeting at nucleoli in different tumor cells and its role in carcinogenesis to deepen our understanding of the mechanism of MK involved in carcinogenesis.
仁用杏新品种‘薄壳1号’  [PDF]
张玲,李炳仁,翟明普,李建宏,侯智霞,苏淑钗,郭素娟,魏淑贞,李建军
园艺学报 , 2008,
Abstract: ‘薄壳1号’是仁用杏‘优一’的实生栽培变种,丰产性强,盛果期平均株产杏核11.1kg,出仁率42.35%~45%。核壳厚度0.9~1.12mm,具有结果量越大,核壳越薄的特性。
寻找最初的“仁”  [PDF]
武树臣
中外法学 , 2014,
Abstract: “仁”是中国古代最重要的观念。尽管关于甲骨文中有无“仁”字尚无定论,但是甲骨文已经有了“仁”字的原形。从“夷俗仁”、“相人耦”的风俗习惯入手,可以发现仌、夾、乘、化、尼、弔六个字形,分别是东夷民族二人相亲、抱哺其子、抵足而眠、靠背而卧、男女之爱、追孝父母诸风俗的写照,它们共同成为酿造“仁”的文化土壤。西周有“心”符之“德”源于并超越殷商无“心”符之“德”,其强调“怀保小民”、“以民为鉴”,可能系受东夷“相人偶”精神的影响。西周的“德”字与战国时的“忎”(仁的古字)之间存在联系。“忎”最早源于母亲对胎儿的关心。从人从二的“仁”字,最早见于西周晚期的《夷伯夷簋器铭》,比学术界公认的首次见于战国时期平山中山王墓铜器铭文中的“仁”字,要早约五百余年。“仁”经过孔子的加工上升为完整的思想体系和推动中国古代社会从野蛮不断走向文明的精神支柱。
Structural features of nucleoli in blood, leukemic, lymphoma and myeloma cells  [cached]
K Smetana
European Journal of Histochemistry , 2010, DOI: 10.4081/1661
Abstract: At present, it seems clear that the nucleolus is multifunctional and represents one of the key cell organelles that participate directly or indirectly in cell resting, proliferation, differentiation and maturation states, and possibly also in programmed cell death. Thus, the morphology and cytochemistry of nucleoli may represent a very useful tool not only for the evaluation of nucleolar biosynthetic activities but also for the evaluation of various cell states under physiological, experimental and pathological conditions.
Apoptosis in mouse fetal and neonatal oocytes during meiotic prophase one
Fataneh Ghafari, Carlos G Gutierrez, Geraldine M Hartshorne
BMC Developmental Biology , 2007, DOI: 10.1186/1471-213x-7-87
Abstract: Microspreads of fetal and neonatal ovarian cells underwent immunocytochemistry for meiosis- and apoptosis-related markers. COR-1 (meiosis-specific) highlighted axial elements of the synaptonemal complex and allowed definitive identification of the stages of meiotic prophase I. Labelling for cleaved poly-(ADP-ribose) polymerase (PARP-1), an inactivated DNA repair protein, indicated apoptosis. The same oocytes were then labelled for DNA double strand breaks (DSBs) using TUNEL. 1960 oocytes produced analysable results.Oocytes at all stages of meiotic prophase I stained for cleaved PARP-1 and/or TUNEL, or neither. Oocytes with fragmented (19.8%) or compressed (21.2%) axial elements showed slight but significant differences in staining for cleaved PARP-1 and TUNEL to those with intact elements. However, fragmentation of axial elements alone was not a good indicator of cell demise. Cleaved PARP-1 and TUNEL staining were not necessarily coincident, showing that TUNEL is not a reliable marker of apoptosis in oocytes.Our data indicate that apoptosis can occur throughout meiotic prophase I in mouse fetal and early postnatal oocytes, with greatest incidence at the diplotene stage. Careful selection of appropriate markers for oocyte apoptosis is essential.The aim of this study was to identify and quantify apoptosis at different stages of meiotic prophase I in mouse oocytes, in order to explore the relationship between chromosomal activity during meiosis, and the occurrence of cell death by apoptosis.Most mammalian oocytes die long before they reach maturity, having no direct role in forming the next generation. Extensive loss of immature oocytes occurs at various stages in mice: (1) during meiotic prophase I, the prenatal process of oocyte formation; (2) in the first days after birth when oocytes that have not been enclosed into primordial follicles suffer demise and (3) when the ovarian follicle that nurtures the oocyte succumbs to atresia. Follicular recruitment, growth and a
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