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981.
鸡胚成纤维细胞(CEF)的来源方便,制备简单,耐受性好,且适合于许多病毒的生长繁殖,因此被广泛用于疫苗的生产、病毒的培养以及一些细胞和分子生物学的研究。然而传统的鸡胚成纤维细胞制备方法存在制备时间长、死细胞较多和细胞贴壁慢的问题。笔者根据经验摸索出一种实验室快速制备CEF的简便方法,并通过台盼蓝染色用细胞计数法绘制了原代CEF及次代CEF的生长曲线。该简便方法的建立为实验室快速制备高质量高纯度的鸡胚成纤维细胞提供了方便,同时对其生长曲线的测定也为进行基因转染方面的研究积累了资料。  相似文献   
982.
以樟树1a生枝条为接穗,采用不同树龄的母树、不同的季节和不同的嫁接方法进行嫁接试验。试验结果表明,不同树龄的母树、不同季节和不同的嫁接方法嫁接成活率都存在较大的差异。树龄低的母树枝条比树龄高的母树枝条嫁接成活率高;春季嫁接成活率最高;切接成活率高。  相似文献   
983.
The present study developed and validated a species-specific loop-mediated isothermal amplification (LAMP) assay for the rapid detection and discrimination of two benign bovine Theileria species – T. sergenti and T. sinensis. The LAMP assay is inexpensive and easy to perform and involves a rapid reaction-the amplification can be performed in 55 min or 50 min under isothermal conditions of 61 °C or 63 °C, respectively, by employing a set of four species-specific primer mixtures. The results can be checked using agarose gels. The optimal assay conditions, under which the assay exhibited with no cross-reaction with other closely related tick-borne parasites (T. annulata, Babesia bovis, B. bigemina, B. major, B. ovata, B. U. sp., Anaplasma marginale) or between the two Theileria species of interest, was established. The assay is approximately 10-fold more sensitive than the conventional specific PCR assay. The LAMP assay was validated using DNA from 6 standard stocks in the laboratory and was evaluated for its diagnostic utility using blood samples collected from experimentally and naturally infection cattle or yaks in China. These findings indicate that this Theileria species-specific LAMP assay may have potential clinical applications for the detection and differentiation of two benign bovine Theileria species – T. sergenti and T. sinensis, especially in endemic countries.  相似文献   
984.
对饲养在圆木桶、墙洞、活框蜂箱中10年以上的中蜂蜂群进行工蜂标准采集,测定其工蜂的40个形态指标,对比分析吻长等9个与生产力相关的指标,结果表明,对圆木桶、墙洞、活框蜂箱三种饲养方式进行人为干预,能使中蜂蜂群与生产力相关的形态指标得到优化。  相似文献   
985.
利用手工克隆技术培育体细胞克隆莱芜猪   总被引:1,自引:0,他引:1  
为探讨手工克隆技术在克隆中国地方猪种的可行性,本研究组利用手工克隆技术平台,以中国地方猪品种莱芜猪的耳皮肤细胞作为核移植的供体细胞,以体外成熟的猪卵母细胞为受体细胞,进行体细胞克隆猪培养,成功培育了25头克隆莱芜猪。表明手工克隆技术可应用于莱芜猪体细胞克隆,为莱芜猪的保种及育种提供了新的途径。  相似文献   
986.
对出现精神沉郁、食欲减退、拉稀、脚软和共济失调症状,其后死亡,的鸭病例,进行常规诊断、动物试验,结果分离到一株细菌,命名为GDYJS-1.分离株通过生长特性、凝集试验、染色特性及VITEK-32微生物鉴定系统生化试验鉴定为沙门氏菌;16S rRNA基因序列的测定与分析,鉴定为鼠伤寒沙门氏菌.  相似文献   
987.
988.
为了解猪场猪粪氮磷排放情况,试验采集不同地区规模养猪场100份猪粪样本,采用比重法快速测定总氮/总磷含量。结果表明,不同地区养猪场猪粪总氮含量为22.15~24.78 g/kg,平均为23.37 g/kg;总磷含量为11.48~12.86 g/kg,平均为12.15 g/kg;不同生长阶段猪群粪便总氮/总磷含量从大到小依次为种公猪(28.66 g/kg和14.61 g/kg)、育肥猪(27.15 g/kg和14.17 g/kg)、断奶仔猪(21.83 g/kg和11.43 g/kg)、哺乳母猪(21.40 g/kg和11.02 g/kg)、空怀/妊娠母猪(19.49 g/kg和10.21 g/kg)。此结果为我省规模养猪场氮磷排放控制提供了基础数据。  相似文献   
989.
Effects of tannic acid on active aluminum species distribution in different pH tea soils in Yunnan and Jiangxi tea gardens were studied by field observation and laboratory analysis.There were 4 species of active aluminum in the tea soil,i.e.,exchangeable aluminum Al3+,unimer hydroxyl aluminum Al(OH)2+ Al(OH)2+,acid-soluble aluminum Al(OH)30 and humic-acid aluminum Al-HA.Experimental results showed that tannic acid at levels 0 ~0.4 mmol/kg and 0 ~ 2.0 mmol/kg,with the rising of soil pH value,the content of exchangeable aluminum decreased significantly,hydroxyl aluminum,acid-soluble aluminum and humic-acid aluminum were increased gently.When the concentration of tannic acid increased to above 2.0 mmol/kg,the inhibition of higher concentration of tannic acid on content of active aluminum was strengthened with the rising of soil pH value and variation law of 20 ~40 cm soil layer was similar to 0 ~20cm soil layer.Generally speaking,the content of active aluminum in upper layer of soil were more than subsoil and total content of active aluminum in Yunnan tea soils were higher than Jiangxi tea soils.The correlation analysis showed that the soil pH were positively correlated with hydroxyl aluminum,humic-acid aluminum,pHBC (r =0.796,0.960,0.852 ; p < 0.01,0.01,0.01) in 0 ~ 20 cm soil layer.pHBC were significant negative correlated with exchangeable aluminum (r =-904,p < 0.01),hydroxyl aluminum (r =-645,p < 0.05),and with humic-acid aluminum have a positive correlation,correlation coefficient was0.795 (P < 0.05).Meanwhile,the tannic acid addition concentration were 0 ~ 0.4 mmol/kg soils pH were increased significantly,while samples attains a peak pH value afterwards decrease continuously,the relationship between the pH and the concentration of tannic acids accords with the equation:YpH =-0.04CDN +3.82(R2 =0.95,P <0.01).When the concentration of tannic acid up to about 8.0 ~ 12.0 mmol/kg,soil pH keep unchanged.Therefore,we can clearly draw that effects of tannic acid on active aluminum content of the inflection point is not the same in different region of tea garden soil.Low concentration tannic acid can improve the soil content of various forms of aluminum,but with the increase in the amount of tannic acid,the various forms of aluminum content are inhibited.With the soil pH increased,high concentrations tannic acid on the inhibition of the release of active aluminum increased.pH and tannic acid on the total amount of active aluminum garden soil was mutual weakening effect relationship.  相似文献   
990.
Acid soluble collagen (ASC) from scales of croceine croaker (ASC-C) was successfully isolated with the yield of 0.37% ± 0.08% (dry weight basis), and characterized as type I collagen on the basis of amino acid analysis and electrophoretic pattern. The antioxidant hydrolysate of ASC-C (ACH) was prepared through a two-stage in vitro digestion (4-h trypsin followed by 4-h pepsin), and three antioxidant peptides (ACH-P1, ACH-P2, and ACH-P3) were further isolated from ACH using ultrafiltration, gel chromatography, and RP-HPLC, and their amino acid sequences were identified as GFRGTIGLVG (ACH-P1), GPAGPAG (ACH-P2), and GFPSG (ACH-P3). ACH-P1, ACH-P2, and ACH-P3 showed good scavenging activities on hydroxyl radical (IC50 0.293, 0.240, and 0.107 mg/mL, respectively), DPPH radical (IC50 1.271, 0.675, and 0.283 mg/mL, respectively), superoxide radical (IC50 0.463, 0.099, and 0.151 mg/mL, respectively), and ABTS radical (IC50 0.421, 0.309, and 0.210 mg/mL, respectively). ACH-P3 was also effectively against lipid peroxidation in the model system. The antioxidant activities of three collagen peptides were due to the presence of hydrophobic amino acid residues within the peptide sequences. The collagen peptides might be used as antioxidant for the therapy of diseases associated with oxidative stress, or reducing oxidative changes during storage.  相似文献   
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