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41.
通过考察牛体细胞核移植重构胚在无血清培养基(IVD101、G1/G2)条件下培养的囊胚发育率及其质量,从而评估无血清培养基支持牛体细胞核移植重构胚体外发育的能力。采用IVD101和G1/G2对牛体细胞核移植胚胎进行体外培养,并以CR1aa+5%FBS作为对照组。无血清培养基IVD101和G1/G2的囊胚发育率与对照组无显著性差异(41.2%±9.1%、42.2%±10.8%,48.0%±9.2%,P〉0.05)。通过囊胚差异染色和冷冻/解冻胚胎存活率分析胚胎质量,发现无血清培养基ICM/Total略低于对照组(31.8%±10.5%、29.5%±11.9%vs .33.0%±14.8%),但无显著性差异(P〉0.05);3个组别的囊胚经程序化冷冻/解冻后无血清培养基的存活率(IVD101、G1/G2)略高于对照组,但差异不显著(84.8%、80.4%'US.77.3%,P〉0.05)。结果证明无血清培养基(IVD101、G1/G2)可以支持体细胞核移植重构胚的体外发育,且其对程序化冷冻的耐受性与添加血清组(CR1aa+5%FBS)相似。  相似文献   
42.
Background: Mammary tumors are the most common type of tumor in female dogs. The histopathological diagnosis is usually made by a hematoxylin-eosin (HE) staining of the tumor, which then requires a pathologist's judgment for assessment of malignancy. The purpose of this study was to investigate an alternative silver staining of some argyrophilic nucleolar organizer regions (AgNOR) for improving the diagnostic accuracy with mammary tumors.
Hypothesis: There is a correlation between the histopathological diagnosis by AgNOR count and AgNOR area in canine mammary tumors.
Animals: Seventy-three canine mammary tumors from 33 female dogs.
Materials and Methods: The AgNOR staining was evaluated retrospectively in 73 canine mammary tumors with a parallel HE staining as a "Gold Standard." Both a quantitative manual counting method and a qualitative computerized morphometric method were tested.
Result: The result from both methods indicated a clinically relevant difference in the mean values of the AgNOR in the following 4 categories: malignant, benign, hyperplastic, and normal mammary tissue. The counting method was superior, with 89% of the cases given a correct diagnosis of a malignant or a nonmalignant canine mammary tumor. The 2 methods were then compared to test their ability to classify the tumors correctly. Again, the counting method was the most reliable method, with a sensitivity of 80% and a specificity of 76% when the upper 50% of the AgNOR counts were presumed malignant.
Conclusion and Clinical Importance: The results indicated that an AgNOR test could be an aid to pathologists as a prognostic indicator or to assist them in deciding between a benign or a malignant diagnosis in questionable cases.  相似文献   
43.
In this study, we report an outbreak of fowl pox disease in a large commercial layer farm in Iran. Three flocks of this farm were affected. Flock A (23 wk of age), flock B (44 wk of age), and flock C (71 wk of age) showed cutaneous lesions. Beak necrosis was seen at the posterior part of the upper or lower beak. Also, some vesicles were seen in combs, wattles, and eyelids. Beak and comb lesions were scraped and stained with Wright's staining for histopathological examination. Samples showed hyperplasia of epidermis but no Bollinger bodies were seen. Histopathologically, the epidermis had marked hyperplasia (acanthosis) caused by the swelling and increased number of cells in the stratum spinosum. Clinical observations, as well as histopathological findings, led to a diagnosis of fowl pox disease.  相似文献   
44.
45.
黑木耳原生质体制备、再生及单核体荧光鉴定   总被引:1,自引:0,他引:1  
利用正交试验研究了黑木耳原生质体制备、再生的最佳条件,结果表明,原生质体制备最佳条件是酶解温度31℃、酶浓度1.0%、菌龄5d、酶解时间4h,原生质体再生的最佳条件是酶解温度27℃、酶解时间4h、酶浓度1.5%、菌龄11d。稳渗剂种类对黑木耳原生质体再生率的试验结果表明,采用0.5mol/L蔗糖为稳渗剂,各黑木耳菌株的原生质体再生率最高。HW2号菌株原生质体经核染色其单核化比率最高;在荧光显微镜下观察菌丝核相,单、双核清晰可辨。  相似文献   
46.
棉花AFLP银染技术及品种指纹图谱应用初报   总被引:15,自引:7,他引:8  
本文介绍了一种适合于棉花研究的AFLP银染方法,并利用该方法获得了几个棉花品种的指纹图谱  相似文献   
47.
 Bacterial cells may be immobilized in soil through adsorption to a variety of soil particles. These associations affect the interaction of native soil microbes with their nutrient sources and control at least in part the distribution of foreign bacteria entering the soil system. To observe the relationship between soil structure and adsorption of amended bacterial cells, a series of intact cores of Freehold fine sandy loam were inoculated with suspensions of Arthrobacter crystallopoietes cells at concentrations ranging from 106 to 108 cells per ml. The cells were cultivated in a glucose-based medium to induce spherical cell formation. Following inoculation, the soil cores were rinsed with sterile water (30–40 ml h–1), flushed with thiazine red R to stain the bacterial cells, and then prepared for examination by common micromorphological techniques. The use of fluorescence, polarizing, and reflected light microscopy of soil thin sections, allowed direct, qualitative determinations of microbial distribution and associations with soil components. A. crystallopoietes cells were detected throughout the length of the soil columns. Soil pores did not appear to be clogged by the spherical A. crystallopoietes cells. Adsorption of amended bacteria was governed by the presence of both variably charged mineral oxides and organic matter within the intergrain microaggregates and occurred along coated mineral surfaces. Amendment of non-inoculated soil columns with 0.2% (w/v) solution of glucose demonstrated that the staining and sectioning procedure was sufficiently sensitive to detect growth of indigenous bacterial populations and their distributions within the soil matrix. Received; 6 April 1997  相似文献   
48.
建立黑斑原鮡(Glyptosternum maculatum)AFLP反应体系,对DNA提取、双酶切、连接、预扩增、选择性扩增和银染效果进行了探索。结果表明,40μLTaqI酶切体系中65℃先酶切2h,EcoRI酶切和连接同时进行,EcoRI酶和T4DNA连接酶的用量均以2U为宜,温度与时间分别为37℃和3h,连接产物稀释10倍作为预扩增的模板。利用这种优化的反应体系,5对选择性扩增引物组合表现出较高的稳定性、清晰度和多态性,它们分别是:E-AAC/T-AAT、E-AAC/T-AAG、E-AAG/T-ACA、E-AAG/T-AAT和E-AAT/T-AGA。5对引物组合对96个样本扩增,共得到332条清晰可辨、可重复的条带,平均每对引物组合扩增出66.4条带,其中51条带是多态的。将AFLP技术用于黑斑原鮡的研究,通过优化体系的建立,为其种质资源的研究奠定基础。  相似文献   
49.
实验采用Giemsa与Wright' s两种染色方法对黑褐新糠虾血细胞进行染色,根据血细胞大小,所含颗粒与否,颗粒多少和核质比将其分型,并对各型血细胞所占比例进行统计.结果表明,通过比较Giemsa染色与Wright's染色两种方法的染色时间和效果,Wright's染色更加适合糠虾血细胞.通过染色,将黑褐新糠虾血细胞分为3种类型,它们分别为透明细胞、半颗粒细胞和颗粒细胞.它们的胞体大小依次增大,核质比依次降低.对此3种类型血细胞比例分别统计后发现,颗粒细胞所占比例最多约( 48.38%±0.05%),其次是半颗粒细胞约为(35.22%±0.04%),最少的为透明细胞约为(16.40%±0.01%).对不同浓度溶藻弧菌的感染试验发现,日本新糠虾在较短的时间内出现死亡,即48h,而黑褐新糠虾72 h出现死亡,各浓度组中日本新糠虾死亡率均高于黑褐新糠虾.黑褐新糠虾相对日本新糠虾来说,对溶藻弧菌具有较低的敏感性,可能与其血细胞中颗粒和半颗粒比例较高有关.  相似文献   
50.
美洲鲥仔稚鱼脊柱及附肢骨骼系统的早期发育   总被引:2,自引:1,他引:1  
使用软骨-硬骨双染色技术,描述了美洲鲥(Alosa sapidissima)仔稚鱼(1~51日龄)脊柱、胸鳍、尾鳍、背鳍等附肢骨骼的形态发育特征。结果显示,脊柱的发育开始于10日龄仔鱼尾部的髓弓、脉弓和尾下骨的出现,16日龄髓弓和脉弓延伸形成髓棘和脉棘,19日龄脊柱出现分节的硬骨环,23日龄所有椎体形成。各附鳍支鳍骨发育顺序先后依次为胸鳍、尾鳍、背鳍、臀鳍和腹鳍。胸鳍在2日龄时出现乌喙骨,13日龄形成软骨质的胸鳍支鳍骨,19日龄仔鱼肩带和上匙骨开始骨化;尾鳍的尾下骨最早出现在5日龄,12日龄尾鳍形成2枚尾上骨、1枚尾杆骨和6枚尾下骨,19日龄仔鱼尾椎和尾鳍率先开始骨化,直至23日龄尾鳍骨骼系统钙化完全。最终背鳍和臀鳍分别形成18和22根鳍条。美洲鲥骨骼发育研究对其早期发育功能趋向、环境优化及分类鉴定有重要作用。  相似文献   
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