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A. Szczurkowski 《Anatomia, histologia, embryologia》2005,34(S1):51-51
Introduction: The mammalian digital end organ has developed in three basic functional forms, i.e., claw, hoof and nail. Whereas detailed information on the ontogeny and phylogeny of the equine and bovine hooves, and the human nail, respectively, are on hand, such data are still not available for the canine claw. Because phylogenetically the carnivore claw is considered as a primary form of digital end organ, data on the organogenesis of the canine claw will complement current knowledge on onto- and phylogeny of the carnivore claw, and digital end organs in general.
Materials and Methods: Light and electron microscopy of 18 canine fetuses of 40–150 mm crown-rump-length and five puppies aged 1 day–4 weeks post-partum.
Results: The development of the canine claw can be divided into four periods. The first stage is initiated by the differentiation of the connective tissue layers of the claw anlage. The second stage is characterized by formation of the specific claw shape, and the third stage by further regional function-related modifications resulting in the development of the five different segments of the digital end organ. The fourth stage proceeds post-natally when the influence of increasing body weight and weight bearing leads to the final functional adaptation of the papillary body.
Conclusion: The organogenesis of the canine claw resembles that of the feline claw in many aspects, but also shows some specific deviations. In particular, the development of the dorsal ridge – characteristic for the carnivore claw – differs between both species. The results of our study therefore raise the question whether the current hypothesis on allocation of the different segments of the canine claw has to be reconsidered. 相似文献
Materials and Methods: Light and electron microscopy of 18 canine fetuses of 40–150 mm crown-rump-length and five puppies aged 1 day–4 weeks post-partum.
Results: The development of the canine claw can be divided into four periods. The first stage is initiated by the differentiation of the connective tissue layers of the claw anlage. The second stage is characterized by formation of the specific claw shape, and the third stage by further regional function-related modifications resulting in the development of the five different segments of the digital end organ. The fourth stage proceeds post-natally when the influence of increasing body weight and weight bearing leads to the final functional adaptation of the papillary body.
Conclusion: The organogenesis of the canine claw resembles that of the feline claw in many aspects, but also shows some specific deviations. In particular, the development of the dorsal ridge – characteristic for the carnivore claw – differs between both species. The results of our study therefore raise the question whether the current hypothesis on allocation of the different segments of the canine claw has to be reconsidered. 相似文献
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试验将40只7日龄雏鸡分为3组,分别每日经口灌服不同浓度砷溶液和生理盐水,分别于8、10、14、17日龄测定血液红细胞免疫功能及血清中免疫球蛋白含量.结果显示,不同浓度的砷溶液均可以导致雏鸡RBC-C3bR花环率先升高(P>0.05)再降低(P<0.01或P<0.05),RBC-IC花环率先降低(P>0.05)再升高(P<0.01或P<0.05),血液中免疫球蛋白含量也是先微升高(P>0.05)再降低(P<0.01或P<0.05),且呈时间剂量效应.表明砷可影响雏鸡红细胞免疫功能及血清中免疫球蛋白的含量,降低雏鸡血液的免疫功能. 相似文献
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树突状细胞(DC)是目前发现功能最强的一类抗原递呈细胞(APC),因其在机体免疫应答及免疫功能发挥中担当重要角色,成为免疫学研究热点。多糖是中药黄芪的重要有效成分,由己糖醛酸、果糖、阿拉伯糖、半乳糖醛酸等组成,具有免疫调节、抗肿瘤、抗应激和抗氧化等作用。黄芪多糖的免疫调节一直是人们研究的重点,研究发现其可通过促进DC成熟而发挥免疫调节作用。论文从DC的形态和功能变化、DC的成熟和DC表面标志CD80、CD86、CD83和相关细胞因子表达等方面,综合分析了黄芪多糖对DC抗原递呈能力的影响。 相似文献
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鸭胰腺内高血糖素—,胰岛素—和生长抑素—免疫反应细胞的形态及分布 总被引:1,自引:0,他引:1
用ABC免疫组织化学方法,对1 周龄绍鸭胰腺内的高血糖素(A)、胰岛素(B)和生长抑素(D)免疫反应细胞的形态及分布进行了观察。结果表明,上述3 种细胞在全胰的分布及形态有差异。A 细胞主要成群散在于A 胰岛,少数位于混合型胰岛的边缘。D 细胞主要散在于A 胰岛中,少数位于B胰岛和混合型胰岛的边缘。B细胞主要呈团块状分布于B胰岛,少数位于混合型胰岛的中央。在胰外分泌部有散在的A 和D 细胞,位于腺泡及导管上皮细胞之间或结缔组织中。A 细胞形态各异,以多边形为主,多数细胞伸出形态多样的胞质突起,伸达胰岛或其他细胞间。D细胞的形态与A 细胞相似。B细胞形态均一,呈圆形或卵圆形,未见胞质突起,在外分泌部未见到B细胞。 相似文献
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A review of the literature concerning the origin, function and fate of the globular leukocyte is presented. The possible relationship of this cell to other cells such as erythrocytes, mast cells and lymphocytes in general is discussed with an aim toward delineating the probable functions of the cell. Although the globular leukocyte has been described in many species and in a variety of organs, its origin, fate and function remain to be clearly elucidated. 相似文献
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在前期功能性试验基础上 ,根据商品化要求 ,将蜂胶制剂制成乳化型制剂和与蜂蜜混合型制剂等 ,以此为样品与前期制剂和市场同类制剂进行功能性比较试验。实验证明 :该乳化制剂在总黄酮含量、抗菌活性、降血糖等生物学功能上均优于或接近其他产品 相似文献
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为建立成年小鼠睾丸间质细胞分离纯化方法,并对分离纯化的睾丸间质细胞进行睾酮分泌功能检测,对成年小鼠睾丸组织进行Ⅰ型胶原酶消化、Percoll分离液密度梯度离心,分离成年小鼠睾丸间质细胞.细胞纯度用3β-羟类固醇脱氢酶(3β-hydroxy-steroid-dehydrogenase,3β-HSD)染色鉴定.将分离纯化的睾丸间质细胞进行体外培养,在基础睾酮和人绒毛膜促性腺激素(hCG)刺激培养条件下,用放射免疫分析法对培养上清中的睾酮含量进行检测.结果显示,通过该方法能获得高纯度成年小鼠睾丸间质细胞(>95%),培养的睾丸间质细胞具有分泌基础睾酮以及对hCG刺激反应的能力.提示采用该方法对成年小鼠睾丸间质细胞进行分离纯化具有高效性、可用性,通过该方法获得的睾丸间质细胞是体外研究药物对睾酮分泌功能影响的良好模型. 相似文献
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利用扫描电镜对苜蓿(Medicago sativa)花器官的发育过程进行详细研究.结果表明:在电镜下将苜蓿花器官的发育分为明显的8个阶段,S1阶段出现初级花序分生组织(I1)和次级花序分生组织(I2)的分化;S2阶段次级花序分生组织发育为花分生组织(F)和苞片(Br);S3阶段出现萼片原基(Sab);S4阶段分化心皮原基(C)和共同原基;S5阶段共同原基分化为花瓣原基(P)和雄蕊原基(STp);S6阶段萼片开始伸长,并覆盖其他花原基,两侧的雄蕊原基(STs)和靠近心皮的雄蕊原基(STp)开始分化雄蕊;S7阶段旗瓣和翼瓣分化明显,龙骨瓣融合,柱头折叠在未成熟的雄蕊之间,雄蕊分化明显;S8阶段整个花器官发育完成,柱头开始伸展,花药生长趋于成熟.淮阴苜蓿雄蕊原基产生四棱形的花药原始体,淮阴苜蓿花粉粒属N3P4C5型.该试验将对苜蓿雄性不育、自交不亲和、花的发育模式、花药培养及相关花的突变体育性的研究奠定基础,并对苜蓿花发育的分子生物学和发育遗传学研究提供指导. 相似文献
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支持细胞对维持精子形成过程中的微环境起决定作用,它可以通过分泌功能、细胞间连接形成的血睾屏障功能以及吞噬功能等来促进精子的形成过程,其发育异常会导致不同程度的雄性生殖缺陷。基于支持细胞在雄性动物生殖过程中的作用,体外培养高纯度支持细胞可成为研究睾丸两大核心功能-精子发生和性激素分泌功能相关调节机制重要的细胞模型。此外,体外培养睾丸支持细胞也可作为生殖毒理学等新兴热点领域的细胞模型,为评估和研究环境因素对雄性生殖的影响提供便利。因此,作者系统地归纳、总结了目前关于动物支持细胞生物功能的研究及常用的体外分离纯化、培养及鉴定方法,以期为利用动物支持细胞开展雄性生殖领域的研究提供参考。 相似文献
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为探讨表面抗原修饰后猪红细胞异源输血的可行性,采用α-半乳糖苷酶和单甲氧基聚乙二醇琥珀酰亚胺碳酸酯(mPEG-SC)对猪红细胞进行双修饰后,体外检测红细胞的渗透脆性,并进行配血试验和犬输血试验。观察输血前后犬的各项临床指标变化,并对其进行血常规和尿常规的连续检测分析。结果表明,修饰红细胞渗透脆性降低,体外配血未出现凝集反应。输血后亦未引起明显的临床异常反应,血常规及尿常规正常。说明猪红细胞体外双修饰后进行首次异源输血具有可行性,可作为动物通用血源用于临床。 相似文献
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为了调查运输应激对伊犁马血细胞和血液生化指标的影响,试验选取6匹伊犁母马,进行400 km里程的运输,总运输时间为8 h,分别在运输0、4、8 h和落地12 h后,测定马血清急性期蛋白(APPs)、皮质醇(Cor)、热休克蛋白(HSPs)、干扰素-γ(IFN-γ)和肿瘤坏死因子-α(TNF-α)含量以及血液常规指标。结果显示,与运输0 h相比,运输8 h马触珠蛋白(HP)含量显著上升(P<0.05),运输4、8 h和落地12 h后马血清Cor含量均极显著上升(P<0.01);落地12 h后马血清HSP90含量极显著下降(P<0.01);运输对马血清IFN-γ和TNF-α含量均无显著影响(P>0.05);运输4、8 h和落地12 h后血液红细胞分布宽度标准差(RDW-SD)、血小板分布宽度(PDW)、血小板大细胞比率(P-LCR)、粒细胞(GRAN)和粒细胞比率(GRAN%)均显著上升(P<0.05),中间细胞比率(MID%)、中间细胞(MID)、血红蛋白浓度(MCHC)均显著下降(P<0.05)。综上所述,运输应激对马血清HP、Cor、HSP90浓度、血液RDW-SD、PDW、P-LCR、GRAN%、GRAN、MID%、MID和MCHC均产生显著影响,这些指标可用于评价马对运输应激的敏感性。 相似文献
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Veslemy Myhrvold 《Acta veterinaria Scandinavica》1980,21(4):498
The cryoprotection of hen erythrocytes, used as reagent in virus titration, was investigated. The cryoprotective agents tested were neutralized polyvinylpyrrolidone (PVP), dimethylsulfoxide (DMSO) and glycerol. Good results were obtained with PVP, especially with PVP K15 (average molecular weight 10 000), and with DMSO, especially when used in a final concentration of 10 %, whereas glycerol was unfit for use in the concentrations tested. The red cell concentration, the suspending buffer before freezing and the washing procedure after thawing were of importance. The cells could be frozen and stored for at least three months without any significant effect on the virus titer. 相似文献