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早熟和正常中华绒螯蟹大颚器官发育及超微结构   总被引:5,自引:0,他引:5  
对早熟和正常发育的中华绒螯蟹(Eriocheirsinensis)大颚器官(mandibularorgan,MO)进行解剖学和组织学研究,发现早熟蟹的MO在当年秋季已充分发育,MO细胞直径在当年11月达到最大值;而正常发育幼蟹的MO在当年细胞排列紧密,直到翌年秋季才充分发育。正常发育成蟹(二秋龄蟹)的MO细胞直径在10月达到最大值,明显大于早熟蟹(P<0.05)。表明早熟蟹MO较正常发育蟹提早一年发育,但是,秋季早熟蟹MO的发育速度和发育良好程度均不及二秋龄蟹MO的发育,这可能是早熟蟹卵黄发生过程较缓慢,较二秋龄蟹滞后约一个月达到次级卵黄发生末期的原因。中华绒螯蟹MO细胞超微结构的显著特征是丰富而形态多样的光面内质网和具小管状内嵴的线粒体,以及丰富的游离核糖体。  相似文献   
24.
对早熟和正常发育的中华绒螯蟹(Eriocheirsinensis)大颚器官(mandibularorgan,MO)进行解剖学和组织学研究,发现早熟蟹的MO在当年秋季已充分发育,MO细胞直径在当年11月达到最大值;而正常发育幼蟹的MO在当年细胞排列紧密,直到翌年秋季才充分发育。正常发育成蟹(二秋龄蟹)的MO细胞直径在10月达到最大值,明显大于早熟蟹(P<0.05)。表明早熟蟹MO较正常发育蟹提早一年发育,但是,秋季早熟蟹MO的发育速度和发育良好程度均不及二秋龄蟹MO的发育,这可能是早熟蟹卵黄发生过程较缓慢,较二秋龄蟹滞后约一个月达到次级卵黄发生末期的原因。中华绒螯蟹MO细胞超微结构的显著特征是丰富而形态多样的光面内质网和具小管状内嵴的线粒体,以及丰富的游离核糖体。  相似文献   
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In this study, we report the features of an adenocarcinoma with giant cell formation spontaneously occurring in the accessory sex glands of a male 10-month-old Sprague-Dawley rat. A milky white mass was found in the region corresponding to the left seminal vesicle and the left coagulating gland. Histologically, tumor cells exhibited diverse growth patterns, including glandular/trabecular, cystic, and sheet-like growth areas. The tumor cells were pleomorphic, with round- or oval-shaped nuclei and abundant eosinophilic cytoplasm. Mitotic figures were occasionally observed. Giant cells were also prominent in the sheet-like growth area, with intracytoplasmic vacuoles containing eosinophilic material. The stroma was rich in collagen fibers and fibroblasts. Numerous inflammatory cells were observed in the glandular and cystic lumina and stroma. Immunohistochemically, the tumor cells were positive for cytokeratin AE1/AE3 and proliferating cell nuclear antigen. In the sheet-like growth area, some of the tumor cells and giant cells were positive for vimentin in the cytoplasm adjacent to the nucleus. Electron microscopy revealed that the tumor cells contained a small number of mitochondria and rough endoplasmic reticulum, and had no basement membrane or desmosome. The giant cells occasionally contained variably sized intracytoplasmic lumina and globular filamentous bodies, probably corresponding to vimentin. Considering these morphological features, the tumor was diagnosed as an adenocarcinoma with the formation of giant tumor cells originating from the male accessory sex glands.  相似文献   
26.
大豆耐盐性研究进展*   总被引:16,自引:2,他引:14  
於丙军  刘友良 《大豆科学》2000,19(2):154-159
本文从离子毒害、膜脂和蛋白质组分改变、活性氧伤害、根瘤和盐腺等方面,概述了有关大豆耐盐性的研究进展。阐明了大豆右以通过渗透调节、膜组分改变、清除活性氧等生理机制增强抗盐性,还可通过根瘤、盐腺等形态结构适应盐逆境。指出了提高大豆耐盐以进行盐土生物改良和综合开发的可能途径及今后的研究方向。  相似文献   
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Mammary gland is a kind of exocrine glands and a dynamic organ.Structure of mammary gland changes throughout the female reproductive cycles.Development of mammary gland occurs in the defined stages that are closely linted to sexual development and reproduction, namely embryonic, prepubertal and pubertal stages, pregnancy, lactation and involution.In this review, the roles of epithelial-stromal (mesenchymal) interactions in embryonic and postnatal mammary development were summarized, elaborated the regulations of different kinds of hormones on the mammary development after pubertal stage, and described the discovery of mammary stem cell populations (MaSC) and selection markers of mice and human.The objective of this work was to learn the basic processes and potential regulation mechanisms of the mammary development to provide some help for the researchers in the field of mammary gland.  相似文献   
28.
目的 :研究微量元素加复合释放系统对修复大鼠颌骨缺损的影响。方法 :72只 SD大鼠随机分为 3组 ,左侧下颌骨体部造成全层骨缺损。缺损被脱骨基质 (DBM)或脱钙骨基质复合释放系统 (DBM± DS)充填。术后 ,微量元素行二组灌胃。术后 2、4、8周 ,通过组织学及 X线分析评价骨缺损修复效果。结果 :双因素应用组 (微量元素液及释放系统联合应用 )其骨痂出现和骨形成早于两单因素组 ,且在三时段新骨形成较多。结论 :复合微量元素脱钙骨基质释放系统能促进颌骨缺损新骨的形成  相似文献   
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The complexity of the equine skull makes the temporomandibular joint a difficult area to evaluate radiographically. The goal of this study was to determine the optimal angle for a complementary radiographic projection of the equine temporomandibular joint based on a computed tomography (CT) cadaver study. CT was performed on six equine cadaver heads of horses that were euthanized for other reasons than temporomandibular joint disease. After the CT examination, 3D reconstruction of the equine skull was performed to subjectively determine the angle for a complementary radiographic projection of the temporomandibular joint. The angle was measured on the left and right temporomandibular joint of each head. Based on the measurements obtained from the CT images, a radiographic projection of the temporomandibular joint in a rostral45°ventral-caudodorsal oblique (R45°V-CdDO) direction was developed by placing the X-ray unit 30° laterally, maintaining at the same time the R45°V-CdDO angle (R45°V30°L-CdDLO). This radiographic projection was applied to all cadaver heads and on six live horses. In three of the live horses abnormal findings associated with the temporomandibular joint were detected. We conclude that this new radiographic projection of the temporomandibular joint provides superior visualization of the temporomandibular joint space and the articular surface of the mandibular condyle.  相似文献   
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对成年果子狸生殖腺(卵巢、睾丸)进行大体解剖和显微观察,发现其生殖腺随季节性繁殖而出现周期性变化,繁殖旺季性腺明显增大且具有丰富的各级生殖细胞;休情期则显著缩小,性腺活动处于停滞状态,没有成熟的生殖细胞。  相似文献   
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