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1.
The mast cells from the mammary gland of the cow greatly resemble the mast cells of man and small laboratory animals. However, certain ultrastructural differences are found in the mast cell granules. These granules are divided into four different types according to their morphology. All contain a granular material of varying fineness, bounded by a membrane. In addition a fibrous or crystalline part is found in some granules, while in others a large light vacuole can be seen. All the granules are surrounded by a unit membrane. 相似文献
2.
The fine structure of the tapetum lucidum of the domestic cow was studied by electron microscopy. In this ungulate the reflective layer is a tapetum fibrosum situated in the choroid and mainly restricted to the superior fundus. The tapetum is composed of a large array of fine extracellular collagen fibrils separated into lamellae by fibrocytes. The collagen fibrils display the normal cross-striations of native collagen, are 0.2 μm in diameter and are arranged in a hexagonal pattern with a center-to-center spacing of about 0.2 μm. The diameter and spacing of these fibrils is consistent with the constructive interference of reflected light. A vascular lamella adjacent to the retinal epithelial layer contains the choriocapillaris and some irregularly arranged collagen fibrils. The tapetum is pierced by blood vessels which supply the choriocapillaris. Over the tapetum the retinal epithelium is non-pigmented while in nontapetal regions this layer is pigmented. The choriocapillaris is not indented into the retinal epithelium as is the case in species with a tapetum cellulosum. 相似文献
3.
用透射与扫描电镜和荧光显微镜对25只成年母鸡的松果腺进行了系统观察。松果腺主要由松果体细胞组成,其间夹杂有少量胶质细胞。松果体细胞的核呈圆形或椭圆形,而胶质细胞的核多呈不规则形。松果体细胞具有突起,线粒体丰富,高尔基复合体发达,胞质中散布有核糖体,并见有粗面和滑面内质网、微管、溶酶体、脂滴以及少量致密核芯小体和板层小体。胶质细胞的结构特征为胞质中含有微丝。毛细血管内皮不含窗孔。本研究结果表明,鸡松果体细胞具有内分泌细胞的结构特征,因而认为鸡的松果腺是一个内分泌腺。 相似文献
4.
为研究中药对奶牛乳腺抗氧化能力的影响,选取7种中草药(王不留行、黄芪、漏芦、木通、通草、蒲公英、甲珠)测定其对体外培养的奶牛乳腺上皮细胞抗氧化能力的影响.测定了奶牛乳腺上皮细胞中的超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、过氧化氢酶(CAT)活性、丙二醛(MDA)质量分数、一氧化氮(NO)含量和一氧化氮合酶(NOS)活性.结果表明中药组奶牛乳腺上皮细胞SOD、GSH-Px和CAT活性高于或显著高于正常对照组(P>0.05,P<0.05,P<0.01),MDA、NO、NOS质量分数低于或显著低于正常对照组(P>0.05,P<0.05,P<0.01).中药能减少脂质过氧化产物MDA的生成,同时提高奶牛抗氧化酶活性,增强了奶牛的抗氧化能力. 相似文献
5.
The purpose was to study the fine structure of the cells and the histochemistry of the mucosubstances of the porcine bulbourethral gland. The material comprised adult boars from the Danish Landrace, two for electron microscopy and 10 for ordinary histology and histochemistry. The methods included histology, electron microscopy and histochemical tests on mucosubstances. The fine structure of the cells and the histochemistry of the mucosubstances of the secretory granules were described. The functional aspects of the findings were discussed. 相似文献
6.
Clinical findings, surgical repair and postsurgical care of a unilateral fracture of the mandible of a bull and of a bilateral mandibular fracture in a horse are described. Compression plating limited the pain suffered by the animals and resulted in a quick return to function of the mandibles. 相似文献
7.
利用高保真PCR法,分别扩增了牛乳腺β-酪蛋白基因的1.8和1.1 kb的5′和3′调控序列,将其分别克隆入TA载体。经PCR验证后测序,用NCBI Blast软件分析表明其克隆片断与奶牛β-酪蛋白基因相应区域同源性分别为97.0%和99.0%,表明成功克隆了酪蛋白基因5′和3′的调控区。然后利用DNA重组技术依次亚克隆入改造过的真核表达载体pcDNA3(切除CMV启动子),构建成牛乳腺特异表达载体。获得的重组载体经限制性内切酶酶切鉴定,测序验证等表明,成功构建了牛乳腺特异表达载体。 相似文献
8.
本试验旨在研究中药王不留行增乳活性单体邻苯二甲酸二丁酯及催乳素对奶牛泌乳中期乳腺上皮细胞miRNAs表达的影响;荧光定量RT-PCR检测增乳活性单体邻苯二甲酸二丁酯及催乳素作用后乳腺上皮细胞miRNAs表达变化;王不留行增乳活性单体邻苯二甲酸二丁酯及催乳素均抑制原代培养的泌乳中期奶牛乳腺上皮细胞miRNA-143、miRNA-125和miRNA-195表达;邻苯二甲酸二丁酯可抑制miRNA-21表达,催乳素对miRNA-21表达的影响尚不确定。首次阐明中药王不留行增乳活性单体邻苯二甲酸二丁酯和催乳素能引起乳腺上皮细胞miRNAs表达变化。 相似文献
11.
乳腺是奶牛乳汁合成的重要器官,乳腺内营养物质代谢与乳品质密切相关。乳蛋白作为乳中最重要的营养物质,一直受到研究者关注。氨基酸是乳蛋白合成的重要前体物,同时也是乳腺代谢途径的重要调控因子。乳腺内氨基酸代谢涉及诸多信号通路,对信号通路的深入研究可从细胞分子水平揭示乳合成调控机理,为奶牛乳腺内氨基酸代谢营养调控提供理论依据。本文针对奶牛乳腺氨基酸代谢及其涉及到的信号通路进行综述,并就其与营养的关联进行了阐述。 相似文献
12.
本文提出了一种新的测定王浆腺活性的方法——10-HDA法,其理论依据是:王浆腺在离体培养时,必然把合成的王浆分泌在培养液中,因此培养液中10-HDA含量,可以直接反映出培养液中的王浆含量,从而间接地反映出王浆腺的活性。 相似文献
13.
Mastitis was produced in three first calf heifers by inoculation of the udder with the virus of infectious bovine rhinotracheitis. These animals were killed at different times during the course of the disease and tissues were harvested and examined histologically. The basic lesion resulted from the necrotizing effect of the virus upon the epithelial cells of the alveoli and ducts. Eosinophilic intranuclear inclusion bodies were demonstrated in tissues from animals killed at three and six days postinoculation, but not at nine days. Of interest was the presence of a large Reed-Sternberglike cell in tissues of the last two animals killed. 相似文献
14.
奶牛乳腺炎是危害奶牛养殖业最常见的疾病之一,给奶牛生产造成巨大的经济损失。其乳腺防御机理、发病机理虽取得了一定的研究成果,但深层次的一些问题仍然未能弄清楚,在这方面还需继续进行大量的研究工作。现就国内外奶牛乳腺自我防御方面的一些机理进行讨论,从乳汁血液当中的免疫活性细胞、体液因子、细胞因子等对乳腺防御方面的功能作详尽的叙述,尤其对泌乳周期中各种白细胞群的分布、功能以及影响奶牛围产期阶段免疫机能下降的一些因素作了分析,对了解和预防奶牛乳腺炎的发生具有一定的参考和应用价值。 相似文献
15.
The aim of the study was to investigate cytological characteristics of principal cells in the proximal caput epididymidis of the ram. Young, sexually mature rams were used. The epididymis was fixed by local vascular perfusion with glutaraldehyde. Samples for histology were embedded in paraffin wax. Small samples for electron microscopy were immersed in osmium tetroxide and embedded in Epon. Signs of pinocytosis and vesicular merocrine secretion were seen, as well as numerous small basal lysosomes. The distal end of the segment showed lower cells with little evidence of secretion. 相似文献
16.
深入研究乳腺组织的免疫防御对制定控制乳腺炎的措施非常重要。乳腺的先天性免疫是一个非常广泛的研究领域,尽管经过多年的研究,但目前对乳腺先天性防御的相关知识仍旧非常缺乏。本文综述了近年来关于奶牛乳腺组织的体液防御在其先天性免疫中的功能和作用机制的研究结果。 相似文献
17.
Experimental infections were produced in 78 quarters of 17 cows by the infusion of small numbers of a single strain of Staphylococcus aureus. In each single experiment three quarters in a cow were infected, with the fourth left as a control. At times varying from three to 60 days after the infusion of organisms, a standard intramammary antibiotic treatment was administered on a single occasion. A cure was arbitrarily defined as the absence of the organism in foremilk, from direct plating and replated incubated milk, together with return to normal somatic cell count levels as determined by an electronic counter. With these standardized conditions the effects of a number of cow associated factors on the outcome of the therapy were determined. Forty-three of the 78 quarters (55%) were cured by the standard treatment. Significant differences in percentages of quarters cured were found to be associated with the duration of infection before therapy, the lactation age of the cow, the length of time in lactation, somatic cell count in milk at time of treatment, the location of the quarter in the udder and individual cows. No significant effects on the outcome of the standard treatment were found associated with the number of bacteria in the secretion at the time of treatment, previous infection and cure in a quarter nor the season of the year in which treatment was given. Of the 35 quarters in which infection recurred following treatment, organisms were reisolated from 12 within four days, 18 between five and nine days, four between ten and 17 days and one after 28 days. From these data it is apparent that if, as has been suggested, models such as described are to be used for efficacy trials, standardization of some parameters is essential. 相似文献
20.
The distribution of adrenal chromaffin cells in the control beagle dog was investigated. The presence of chromaffin cells in the adrenal medulla, three zones of the adrenal cortex and capsule was identified by staining with H&E, chromium salts and TH (tyrosine hydroxylase) antibody. With H&E stain, there are morphological differences among the chromaffin cells in the medulla, cortex and capsule. In addition, the number of the capsular chromaffin cells was statistically significantly decreased in the 8–9, 11–12 and 15–16 month age groups compared with the 5–6 month age group. Both medullary and extra‐medullary chromaffin cells contained catecholamines, demonstrated via special staining for chromium salts. TH is the first enzyme in catecholamine biosynthesis; it is a useful maker for all cells involved with catecholamine biosynthesis including chromaffin cells. TH antibody confirmed that the extra‐medullary cells were chromaffin cells. Terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) assay for detecting the apoptotic signalling identified the apoptosis of the chromaffin cells in the capsule. 相似文献
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