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871.
牛体外受精胚冷冻保存的研究 总被引:9,自引:0,他引:9
对牛卵泡卵母细胞体外受精(IVF)168h的致密桑椹胚、囊胚用常规快速冷冻法、预冷和不预冷的超快速冷冻法进行了冷冻保存试验。结果表明:IVF囊胚采用含10%甘油的常规快速冷冻法、含2.1mol/L甘油和0.25mol/L蔗糖预冷5min的一步冷冻法及含25%甘油和25%乙二醇预冷5min的玻璃化冷冻法等3种方法进行冷冻保存,解冻后的继续发育率(68.0%,59.0%,65.7%)均无显著差异(P>0.05),可用快速、简便、预冷的一步冷冻法或玻璃化冷冻法替代常规快速冷冻法;IVF致密桑椹胚可用一步冷冻法(2.1mol/L甘油+0.25mol/L蔗糖)和玻璃化冷冻法(25%甘油+25%乙二醇或25%甘油+25%1,2-丙二醇)进行预冷的超快速冷冻保存;冻前预冷(5min)能显著提高IVF囊胚的冻后形态正常率和继续发育率(P<0.05);IVF囊胚冷冻—解冻后的继续发育率高于IVF致密桑椹胚。 相似文献
872.
Horizontal starch-gel electrophoresis was used to study crude enzyme extraction from young leaves of 234 clones of Populus tomentosa Carr. selected from nine provenances in North China. Ten enzyme systems were resolved. One hundred and fifty-six clones showing
unusual allozyme band patterns at locus Mdh-1 were found. Three allozyme bands at locus Mdh-1 were 9:6:1 in concentration. Further studies on the electrophoretic patterns of ground mixed pollen extraction of 30 male
clones selected at random from the 156 clones were conducted and it was found that allozyme bands at locus Mdh-1 were composed of two dark-stained bands and a weak band. Only one group of the malate dehydrogenase (MDH) zymogram composed
of two bands was obtained from the electrophoretic segregation of pollen leachate of the same clones. A comparison of the
electrophoretic patterns one another suggested that the locus Mdh-1 coding malate dehydrogenase in diploid species of P. tomentosa was duplicated. The duplicate gene locus possessed three same alleles and was located in mitochondria. The locus duplication
of alleles coding malate dehydrogenase in P. tomentosa was discovered and reported for the first time.
[Supported by the “Tenth Five-year Plan” National Key Project in Science and Technology (Grant No. 2002BA515B0303) and the
National “863” Project (Grant No. 2002AA241071)] 相似文献
873.
To evaluate a novel elemental zinc bolus compared with a registered positive control zinc oxide bolus and assess serum zinc concentrations following concomitant treatment with a capsule containing copper oxide needles. Forty Romney-cross ewes were randomly allocated in a 2 × 2 factorial design study. On Day 0, 20 ewes received novel boluses containing elemental zinc (Investigational Veterinary Product, IVP) while 20 received a zinc oxide bolus (control; CP). Half the animals in each zinc treatment group (n = 10) were treated with a copper oxide needle capsule [Copasure® - Ewe]. Weekly, from Day −7 to 56, all ewes were assessed for signs of photosensitization, and for 10 ewes from each zinc treatment groups, samples were collected for analysis of serum GGT activity, serum zinc concentrations, faecal zinc concentrations and on Days −7 and 56, liver copper concentrations. Multivariable random-effects models assessed the effects of zinc treatment, copper treatment, treatment interactions and time on all analytes. Regression models examined associations between serum and faecal zinc concentrations and GGT activity. Low spore numbers indicated low Pithomyces chartarum challenge. Serum zinc levels were significantly higher in the IVP than in the CP group [p < 0.0001] and varied by time [p < 0.001] and positively associated with faecal zinc concentration [p < 0.001]. Copper treatment did not affect serum zinc [p = 0.82] or faecal zinc [p = 0.92] concentrations. Liver copper concentrations did not differ between zinc treatment groups on Day −7 [p = 0.6] or Day 56 [p = 0.95]. Only the CP/no copper group had no increase in liver copper concentrations. 相似文献
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878.
Population pharmacokinetics of rifampin in the treatment of Mycobacterium tuberculosis in Asian elephants
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E. F. Egelund R. Isaza A. P. Brock A. Alsultan G. An C. A. Peloquin 《Journal of veterinary pharmacology and therapeutics》2015,38(2):137-143
The objective of this study was to develop a population pharmacokinetic model for rifampin in elephants. Rifampin concentration data from three sources were pooled to provide a total of 233 oral concentrations from 37 Asian elephants. The population pharmacokinetic models were created using Monolix (version 4.2). Simulations were conducted using ModelRisk. We examined the influence of age, food, sex, and weight as model covariates. We further optimized the dosing of rifampin based upon simulations using the population pharmacokinetic model. Rifampin pharmacokinetics were best described by a one‐compartment open model including first‐order absorption with a lag time and first‐order elimination. Body weight was a significant covariate for volume of distribution, and food intake was a significant covariate for lag time. The median Cmax of 6.07 μg/mL was below the target range of 8–24 μg/mL. Monte Carlo simulations predicted the highest treatable MIC of 0.25 μg/mL with the current initial dosing recommendation of 10 mg/kg, based upon a previously published target AUC0–24/MIC > 271 (fAUC > 41). Simulations from the population model indicate that the current dose of 10 mg/kg may be adequate for MICs up to 0.25 μg/mL. While the targeted AUC/MIC may be adequate for most MICs, the median Cmax for all elephants is below the human and elephant targeted ranges. 相似文献
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880.
通过采集一匹患病马的病料及后续的病毒分离、病毒核酸提取、RT-PCR、连接T载体等一系列分子生物学技术,对病毒核酸进行测序,经NCBI比对分析,获得一株H3N8亚型马流感病毒。将获得的毒株与我国分离的A/equine/Jilin/1/1989禽源性毒株、2002年美国肯塔基分离株A/equine/Kentucky/1/02(美洲谱系Florida亚型)、A/equine/Argentine/77(美洲谱系Argentine亚型)等有代表性毒株进行同源性分析,发现该毒株与Florida-2型马流感病毒基因片段的同源率最高。根据马流感病毒的命名规则,将这毒株命名为A/equine/Heilongjiang/1/2010。本次所分离到的黑龙江株马流感病毒,丰富了我国马流感病毒资源库,为我国马流感流行病学研究、诊断技术及疫苗研究提供了重要基础。 相似文献