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61.
本文旨在研究采用不同钙源及水平的日粮对肉仔鸡体内电解质平衡及血脂水平的影响.试验采用二因素有重复完全交叉区组设计,选用144只健康AA肉仔鸡,随机分成4处理,每个处理6个重复,每个重复6只.饲粮采用2种钙源(碳酸钙、氯化钙)、2个钙水平(0.90%、1.15%),试验期28 d.结果表明:①与碳酸钙相比,日粮中氯化钙可降低血清Na++K+-Cl-水平(P<0.05)、提高Cl-水平(P<0.05),降低腹脂率(P<0.05)和血脂水平.②高水平钙可提高血清Ca2+水平(P<0.05).降低腹脂率和血脂水平(P<0.05).③钙源和水平互作对各指标均无显著影响(P>0.05).总之,日粮选用1.15%氯化钙虽对电解质平衡产生了一些影响,但可以较好地降低腹脂率和血脂水平.  相似文献   
62.
Cholesterol staining is a useful approach for the visualization, localization and quantification of cholesterol in cells or tissues, which is frequently used to investigate the mechanisms of some diseases such as arteriosclerosis, Niemann-Pick disease type C, and Alzheimer's disease. It can be accomplished through various microscopes including light microscope, fluorescent microscope, and electronic microscope. During the past decades, various types of methods for cholesterol staining with different principles have been established for different applications. It is important to choose an appropriate method that is suitable for particular experimental aims, features and conditions. At present, three kinds of methods are frequently applied: filipin fluorescent method, BCθ(a biotinylated and carlsberg protease-nicked derivative of perfringolysin O) toxin method, and cholesterol oxidase-diaminobenzidine(oxidase-DAB) method. Four kinds of methods are scarcely applied: Schultze method, perchloric acid-naphthoquinone method(PAN), digitonin method, and o-phthalaldehyde method. In this review, the principles, advantages, and disadvantages of these methods are compared with the emphasis of the application, sensitivity, and specificity.  相似文献   
63.
民办学校和公办学校的同等地位问题一直是严重困扰民办学校办学者和教师学生的主要问题之一。虽然《民办教育促进法》已经明确规定了民办学校与公办学校具有同等的法律地位,但是在现实中民办学校无法获得与公办学校同等的法律地位,民办学校教师、受教育者的平等地位和合法权益也得不到充分保障,造成这一现象的根本原因是立法对民办学校法人定位的缺失。  相似文献   
64.
表面活性剂是洗涤剂的必要组分。分析温度与不同表面活性剂的溶解度、表面张力和加溶作用的关系,结果表明,温度对洗涤效果的影响是多方面的。  相似文献   
65.
AIM: To screen the cytotoxicity of degradable calcium metaphosphate (dCMP) compared with hydroxyapatite (HA). The proliferation and differentiation abilities of human marrow mesenchymal stem cells (MSC) were used to exhibit the cytotoxicity. METHODS: The cell morphology of MSC was analysed after direct contact with dCMP at different time points by scanning electron microscopy analysis. The degradation products of dCMP and HA were analysed with inductively coupled plasma torch and ion chromatography. The cytotoxic effect of degradation products of dCMP was evaluated by FACS, quantitative assay of ALP and ARS, respectively. RESULTS: dCMP enhanced the proliferation of MSC, but didn't interfere the osteogenic differentiation process of MSC and its mineralization. HA inhibited the proliferation of MSC and the mineralization of osteogenic differentiated MSC, while it did not interfere the osteogenic differentiation process of MSC. CONCLUSION: dCMP had a better cytocompatibility with MSC than HA, which might allow for its use as skeleton scaffolds.  相似文献   
66.
 小麦类菌原体兰矮病(Wheat Mycoplasna like-oaganism Blue Dwarf-WMBD)是北方麦麦区的一种主要病害,特别是在间套麦田和麦草覆盖保墒的旱农栽培麦区发生严重,其是我国在小麦上新近发现的第一个类菌原体病害。  相似文献   
67.
钙锌对蛋用型鸡育成期体组织中矿物元素含量的影响   总被引:1,自引:0,他引:1  
试验研究了在玉米—豆饼型基础饲粮中添加不同水平锌和钙对蛋用型鸡育成期体组织中矿物元素含量的影响。结果表明,随着饲粮锌水平的提高,肝脏(P<0.01)、肾脏(P<0.05)、胰脏(P<0.01)中锌含量显著升高,而肺脏中锌含量没有显著变化(P>0.05)。饲粮高钙对组织中锌含量的影响未达到显著水平(P>0.05)。饲粮高锌使肝脏磷含量(P<0.05)、肾脏磷(P<0.01)和铜含量(P<0.05)、肺脏钙(P<0.01)和镁含量(P<0.01)显著降低。饲粮商钙使胰脏铜含量(P<0.05)显著提高,使胰脏锰含量显著降低(P<0.05)。  相似文献   
68.
Objective To evaluate seasonal effects on the presence or absence of fungal and aerobic bacterial flora of the conjunctival fornix of normal Florida Thoroughbred horses. Sample population Both eyes of 100 horses. Procedure Horses with normal anterior segment ophthalmic examinations from three farms in north central Florida were included. Each animal had the ventral conjunctival fornix of each eye swabbed with sterile culturettes. Samples were taken in October, January, April, and July (1999–2000). Aerobic and fungal cultures were plated. Bacterial cultures were reviewed at 24 and 48 h. Fungal cultures were reviewed weekly for 4 weeks. Logistic regression analysis with season as a factor and age of the horse as a covariate was performed. Statistical significance was set at P < 0.01. Results Horses ranged from 3 to 24 years of age, with a median age of 9 years. Twenty‐four genera of bacteria and 35 genera of fungi were recovered. Corynebacterium sp., Staphylococcus sp., Bacillus sp. and Moraxella sp. were the bacteria most frequently isolated. Mold species, dematiaceous mold species, Chrysosporium sp., Cladosporium sp., and Aspergillus sp. were the most frequently recovered fungi. Season did not have a significant effect on the presence of microorganisms isolated for individual horses adjusted for age. Younger horses had an increased incidence of gram‐negative rods and fungal isolates. The number of bacteria and fungi isolated are not uniform across seasons. Conclusion There were no significant differences between the number or type of organisms cultured during the sampling seasons in normal Florida horses. A large range of normal bacterial and fungal flora were isolated from these horses. The number of bacteria and fungi isolated are not uniform across seasons. The likelihood of detecting an organism depends on the horses’ age.  相似文献   
69.
Present electron microscopical and immunocytochemistrical studies elucidated some morphological relationship between intercalated duct (ICD) and pancreatic islet cells in the chicken in streptozotocin (STZ) and/or camostat mesilate (CM) administrations. Twenty-one chickens were set into four experimental groups: (1) control group, (2) STZ administration group, (3) CM administration group, and (4) STZ + CM administration group. Cytoplasms of ICD cells stained more strongly with eosin in STZ administration group than other groups, and electron-dense materials and intercalated processes between ICD and islet cells were also increasing in time dependence in STZ administration. Number of pancreatic islet in STZ + CM co-administration was about 3.1 times larger than other groups. Many small sized cells were detected at surrounding area of ICD and they incorporated 5-bromo-2'-deoxyuridine better than other experimental groups. Present morphological data suggested that ICD cells might support some tolerances of pancreatic endocrine cells against toxic substances and also involve in regeneration of new pancreatic islet cells in STZ + CM co-administration.  相似文献   
70.
黄皮种子脱水敏感性与核酸、蛋白质代谢的关系   总被引:3,自引:0,他引:3  
黄皮种子发育晚期,胚内核酸和蛋白质合成能力增强,而花生种子发育晚期则呈下降趋势。脱水处理使生理成熟期黄皮胚核酸和蛋白质合成能力急剧下降,核酸水解酶活性增强。生物大分子代谢能力的变化是黄皮种子脱水敏感性的分子基础。  相似文献   
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