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31.
利用pH调节法制备罗非鱼分离鱼蛋白.在临界pH条件下对罗非鱼肌肉蛋白进行处理得到肌肉溶解蛋白(Solution Muscle Protein,SMP),再利用等电点沉淀法对罗非鱼肌肉溶解蛋白进行分离得到肌肉分离蛋白(Isolated Muscle Protein,IMP),考查SMP的溶解率、黏度及IMP凝胶制品和常规中性漂洗(Conventional Wash)处理得到的蛋白凝胶制品的凝胶强度.以罗非鱼肌肉蛋白质在不同pH下的处理、转谷酰胺酶、食盐及凝胶化温度为因素,凝胶强度为目标参数进行正交试验设计.结果表明,与常规中性漂洗法相比, pH调节法制备的罗非鱼分离鱼蛋白具有回收效果好、功能性强的特点. 相似文献
32.
Cryopreservation of gander semen 总被引:2,自引:0,他引:2
1. The effect of dimethylacetamide (DMA) and dimethyl sulphoxide (DMSO) on the cryopreservation of gander semen were investigated. An improved survival rate of spermatozoa after freeze-thawing was obtained when semen was frozen by a fast-freezing procedure on dry ice with 9% DMA as the cryoprotectant. 2. Gander semen, which was frozen during mid season, was tested for fertilising ability in different times of the season. The percentage of fertility during d 3 to d 9 after 2 consecutive inseminations was 68% to 95%, depending on the date of artificial insemination. 相似文献
33.
Jan C Ramer Roberto Maria Tim Reichard Peter J Tolson Tai C Chen Michael F Holick 《Journal of zoo and wildlife medicine》2005,36(2):188-191
Calcidiol (25-hydroxyvitamin D) values are reported for 22 wild Ricord's iguanas (Cyclura ricordii) and seven wild rhinoceros iguanas (Cyclura cornuta cornuta). Calcitriol (1,25-hydroxyvitamin D) values are reported for 12 wild Ricord's iguanas and seven wild rhinoceros iguanas. These animals were captured as part of a larger health assessment study being conducted on Ricord's iguanas in Isla Cabritos National Park, Dominican Republic. A total of 13 captive rhinoceros iguanas held outdoors at Parque Zoológico Nacional were also sampled for comparison. Mean concentrations of 25-hydroxyvitamin D were 554 nmol/L (222 ng/ml) with a range of 250-1,118 nmol/L (100-448 ng/ml) for wild Ricord's iguanas, 332 nmol/L (133 ng/ml) with a range of 260-369 nmol/L (104-148 ng/ml) for wild rhinoceros iguanas, and 317 nmol/L (127 ng/ml) with a range of 220-519 nmol/L (88-208 ng/ml) for captive rhinoceros iguanas. On the basis of these results, serum concentrations of at least 325 nmol/L (130 ng/ml) for 25-hydroxyvitamin D should be considered normal for healthy Ricord's and rhinoceros iguanas. 相似文献
34.
近年来,畜牧业集约化及规模化养殖发展迅速。因此牲畜调运呈几倍甚至几十倍增长,特别是跨省(区)牲畜调运活动更为频繁。由于在牲畜调运过程中检疫操作程序不完善或手段滞后很大程度上造成了在我国流行很多年的传染病消灭不了,而新侵入我国的传染病却散布很快。这对我们的动物防检工作提出了挑战。下面就跨省(区)牲畜调运过程中检疫操作程序提几点建议,供大家参考? 相似文献
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36.
Holland MS Tai MH Trosko JE Griffin LD Stasko JA Cheville NC Holland RE 《American journal of veterinary research》2003,64(4):396-403
OBJECTIVE: To isolate bovine mammary gland cells with stem cell characteristics. SAMPLE POPULATION: Monolayers of bovine mammary gland cells. PROCEDURE: Mammary gland cell populations were separated by use of selected media supplements. Phenotypic characteristics were examined via light and transmission electron microscopy. Cellular expression of casein and connexin 43 was identified immunohistochemically. A scrape-loading and dye transfer assay was used to examine the mammary gland cell populations for homogenous gap junctional intercellular communication (GJIC). RESULTS: Subpopulations of mammary gland cells grown in vitro are classified on the basis of their distinct morphologic features and ability to communicate via gap junctions. Ultrastructurally, 2 morphologically distinct cell types were classified as type I and II cells. Type I cells were small light undiffertiated cells and large light undifferentiated cells that were deficient in functional gap junctions (as is characteristic of stem cells). Type II cells included large light differentiated cells and terminally differentiated cells; GJIC was functional in type II cells. Type II cells had cytoplasmic expression of connexin 43, whereas, type I cells did not. All cells expressed casein. CONCLUSIONS AND CLINICAL RELEVANCE: Subpopulations of bovine mammary gland cells with stem cell characteristics were identified. Phenotypic differences are observed among type I bovine mammary gland cells with stem cell characteristics. Gap junctional intercellular communication may be necessary for the differentiation of stem cells. Characterization of bovine mammary gland stem cells and their progeny may provide a new tool with which to study mammary gland health. 相似文献
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38.
本文根据多年的实践经验.提出了筑路机械在低温条件下的使用与保养措施.文中对发动机、传动系统、操纵系统、液压系统的使用与保养提出了较为有效的措施,从而保证筑路机械在低温条件下的正常使用. 相似文献
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40.
Wu MC Jiang CM Huang PH Wu MY Wang YT 《Journal of agricultural and food chemistry》2007,55(4):1557-1562
The isolation and utilization of pectin lyase (PL) from commercial pectic enzyme for methanol reduction in wine production was investigated. PL can be separated from pectinesterase (PE) and polygalacturonase (PG) on HM-CL-AIS affinity chromatography at pH 4; however, it is difficult to further distinguish PE from PG. Some desirable physicochemical properties such as transmittance, lightness, redness, and lower total pectin content are found in the external enzyme adding groups (PL, PE and PG, and pectic enzyme groups) in comparison to the control group. Methanol contents in pectic enzyme and the PE and PG groups increase from 628 +/- 13 (control group) to 3103 +/- 16 and 1736 +/- 67 mg/L ethanol in the final products, respectively. Nevertheless, the adding of PL does not cause any increase in methanol content. The results present in this study suggest that the HM-CL-AIS column is a simple, inexpensive, convenient, and effective method for PL purification. Moreover, the partial purified PL is a potential replacement of commercial pectic enzyme for pectin depolymerizing, methanol content reducing, and wine quality improving in wine production. 相似文献