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41.
目的:探讨直肠癌淋巴结转移的相关影响因素,为临床治疗提供参考。方法:回顾性分析施行根治性手术治疗直肠癌患者386例的临床资料,采用卡方检验及Logistic多因素回归分析相关临床病理因素与淋巴结转移的关系。结果:直肠癌患者性别及肿瘤位置与淋巴结转移无关(P〉0.05),而患者年龄(P〈0.05)、肿瘤大小、分化程度、组织类型、肿瘤浸润深度、术前CEA(P〈0.01)与淋巴结转移明显相关;Logistic多因素回归分析得出的与淋巴结转移的相关因素按密切程度依次递减为肿瘤浸润深度、肿瘤分化程度。结论:影响直肠癌淋巴结转移的相关因素有年龄、肿瘤大小、分化程度、组织类型、肿瘤浸润深度、术前CEA,其中肿瘤浸润深度、肿瘤分化程度为淋巴结转移的主要相关因素。 相似文献
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威廉斯香蕉8818及其抗枯萎病突变体的细胞学与组织学研究 总被引:2,自引:0,他引:2
为了比较威廉斯香蕉8818及其抗枯萎病突变体8818-1在细胞学和组织解剖学上存在的差异,对这2种香蕉的体细胞染色体数目、气孔保卫细胞的形态特征和根系细胞结构等进行了相关研究。结果表明,8818和8818-1染色体数目均分布在28~37,属三倍体,其整倍体染色体数目为2n=3x=33,8818和8818-1体细胞中的整倍体个数分别占观察总数的41%和52%,除整倍体外,2者体细胞中还存在大量的非整倍体;8818-1的气孔保卫细胞长度与宽度,气孔密度均比8818大,而2者保卫细胞内叶绿体数目差异不明显;8818-1的根系中导管直径和两穿空板间的距离均显著比8818小,而单位面积上的导管数和薄壁细胞数目比8818多。 相似文献
45.
Javier J. Aguilar Juan Cuervo-Arango Horacio Mouguelar Luis Losinno 《Journal of Equine Veterinary Science》2012
The objective of this work was to study cellular changes in the epithelium of the mare’s oviduct. Oviductal samples were taken from mares at different reproductive stages for optical microscopy and Hoechst 33258 staining. Glandular-like structures were observed in 100% of the oviducts. These structures were of the tubular type and were formed by ciliated and nonciliated epithelial cells arranged in a way similar to the epithelial surface. The amount of structures decreased progressively from the ampulla to the isthmus, but did not change through the different reproductive stages. Histological changes in the epithelium of the oviduct were observed associated with the reproductive stages. In the ampulla, the amount of ciliated cells decreased in the anovulatory phase compared with other reproductive stages. Cords of connective tissue lined by epithelium (trabeculae) and dividing completely the lumen of the oviduct were found in 50% of the oviducts. Epithelial cells projected toward the lumen as large vesicles of cytoplasm, sometimes containing a nucleus. The amount of cells presenting nuclear protrusion varied throughout the oviduct, with highest incidence in the ampulla, decreasing progressively toward the isthmus (P < .05). In addition, nuclear protrusions were higher in number during the anovulatory and luteal phases than in the other reproductive stages (P < .05). These nuclear protruding cells appeared to be extruding from the epithelium and showed no signs of apoptosis based on the histological and fluorescent stains used. The existence of these gland-like structures in the oviductal mucosa should be considered when studying the oviductal physiology in mares. 相似文献
46.
Casteleyn C Simoens P Van den Broeck W 《Veterinary immunology and immunopathology》2008,124(3-4):394-397
This paper describes the presence of lymphoid tissue in the mucosa of the bovine larynx. A total of 15 bovine larynges were examined both macroscopically after tissue fixation in acetic acid and microscopically using histology. It was found that no paraepiglottic tonsil was present in cattle, although a few lymphoid follicles were present in the mucosa at the base of the epiglottis. This result is in accordance with previous reports. In contrast, numerous lymphoid follicles were seen in the mucosa of the epiglottis and the corniculate processes of the arytenoid cartilages. This suggests that larynx-associated lymphoid tissue is present in cattle. Our observation could be of clinical importance, e.g. in the framework of the development of aerosolized vaccines. 相似文献
47.
贻贝雌性生殖系统的组织学研究 总被引:5,自引:0,他引:5
从组织学方面研究了贻贝雌性生殖系统的构造。卵巢壁薄、由外膜和内生殖上皮构成。外膜主要由结缔组绢,意志支上皮和薄层肌肉构成。由其产生的许多延伸物伸入卵巢中把卵巢分成一个个不规则小区。内生死上皮不断增殖平生生殖带,其中含卵原细胞阁阶段雌性生殖细胞和滤泡细胞。卵原细胞较小,核圆形,核仁不明显。初级卵母细胞体积增加,核呈生发泡状,核仁1个,明显。次级卵母细胞卵圆形、细胞体积更大,核仁1个,十分明显。当卵母 相似文献
48.
CPPU对苹果组织形态发育及内源细胞分裂素含量的影响 总被引:2,自引:0,他引:2
苯基脲类细胞分裂素CPPU[Forchlorfenuron:1-(2-chloro-4-pyridyl)-3phenylurea](试验名称为KT-30)是一种活性很高的生长调节物质〔1〕。它对葡萄、梨、猕猴桃以及苹果等多种果树都有促进果实肥大的作用〔4~6〕。本试验对用CPPU处理的红富士苹果进行了果实形态发育、细胞组织学观察及内源细胞分裂素的提取测定等方面的研究,分析CPPU对苹果果实生长促进的作用机理,为该生长调节剂在果树上的有效应用提供科学依据。1 材料与方法1.1 材料对西北农业大学果… 相似文献
49.
应用石蜡切片及HE染色的方法对美洲鲥(Alosa sapidissima)早期发育过程中眼睛的发生、分化和形成过程进行了系统的观察.结果显示,受精后21 h 13 min,视泡出现;受精后26h 23 min,视泡发育成视杯;受精后35 h 44 min,原始视网膜和晶状体形成;受精后60h 15 min,角膜在视网膜前缘处形成,由单一的立方上皮构成;2日龄仔鱼,巩膜分化完成,由软骨组织和弹力纤维构成,脉络膜出现;3日龄仔鱼,虹膜出现,视网膜分化完全,由外向内的色素层、视觉细胞层、外界膜、外核层、外网膜层、内核层、内网膜层、视神经节细胞层、视神经纤维层和内界膜10层构成,此时视觉细胞层中视杆细胞出现;14日龄仔鱼,角膜分化完全,由自外向内的复层扁平上皮、前弹性层、基质层、后弹性层和内皮层5层构成;22日龄仔鱼,脉络膜腺出现;26日龄稚鱼脉络膜分化完全,由外向内依次为银膜层、血管层和色素层,虹膜也完全分化,由外向内依次为虹膜内皮层、前缘层、基质层、后缘层和色素层;45日龄幼鱼,视网膜内核层分化成两层水平细胞.此时美洲鲥眼睛的各个结构均发育完善. 相似文献
50.
R. M. Honji A. M. Narcizo M. I. Borella E. Romagosa R. G. Moreira 《Fish physiology and biochemistry》2009,35(1):109-123
Fecundity and oocyte development in Salminus hilarii female brood stock were analyzed with the aim of investigating the impact of migration impediment on oogenesis. Histological
analyses of the ovaries were performed in adult females caught in two different environments—the Tietê River (natural) and
captivity—and the gonadossomatic index, oocyte diameter and fecundity determined. Five germ cell development stages (oogonium,
perinucleolar, cortical alveoli, vitellogenic, ripe) and two other structures (postovulatory follicles and atretic oocytes)
were observed in females caught in the river. Captive animals lacked the ripe oocytes and postovulatory follicles and had
a relatively higher number of atretic oocytes. Females in captivity are known to produce larger oocytes, and they release
fewer eggs in each spawn (absolute fecundity) when compared with animals that are able to migrate. Our results suggest that
the Tietê River is undergoing alterations which are being reflected in the reproductive performance of S. hilarii, mainly due to the presence of atretic oocytes in females caught in the river. The lack of postovulatory follicles and ripe
oocytes in captive animals reveals that migratory impediment negatively impacts final oocyte maturation. However, the stage
of maturation reached is adequate for ovulation induction with hormone manipulation. 相似文献