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31.
六偏磷酸钠对魔芋葡甘聚糖干法改性研究 总被引:17,自引:0,他引:17
用六偏磷酸钠对魔芋葡甘聚糖进行干法改性。结果表明,反应最佳条件为六偏磷酸钠:魔芋葡甘聚糖=1:8(W/W),在pH1,55℃反应1.5h。其透明度,粘度,冻融稳定性均比对照明显改善;水溶胶具有一定的耐酸、耐高温能力,具有相当的抑菌效果。 相似文献
32.
多媒体技术在现代教学中应用广泛,成效也日益显著,在《动物微生物》教学中应用多媒体技术进行教学,既可丰富学生的理论知识,又能促进学生动手能力的提高。 相似文献
33.
江西是传统的农业大省,要调整农业产业结构,就必须增强广大农村基层干部调整农业产业结构的紧迫感,结合市场需求,发挥我省优势,理清调整思路,尤其在农村政策、农业信息、农产品加工与销售等方面要强化政府服务的职能.只有这样,才能真正做到增加农民收入,减轻农民负担,促进农业发展,保证农村稳定. 相似文献
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Six populations of H. contortus were selected for a study of thiabendazole resistance from a collection of 40 populations made during a survey of the efficiency of thiabendazole on the Northern Tablelands of New South Wales. Based on survey results, 3 of these populations were considered susceptible and the remaining 3 were considered resistant. However, when these populations were compared with a known susceptible strain on the ability of their eggs to hatch in a solution containing thiabendazole and 0.1% NaCl all 6 had significantly greater LC50's. The resistance ratios of the LC50 for each of the 6 populations to that of the known susceptible strain were 5.1, 4.3, 3.2, 3.1, 2.3, and 1.6 respectively. Following dosing of their host with 44 mg/kg thiabendazole the resistance ratios of the survivors increased to 5.4, 5.1, 4.7, 4.4, 3.1 and 2.4. Eggs produced by the F1 generation of the worms surviving 44 mg/kg thiabendazole did not revert back to the lower LC50's of the unselected parents. Rather the LC50 remained at a level near that of a known highly resistant strain of H. contortus. 相似文献
37.
J. N. KING C. MAURON M. J. VOIROL C. LE GOFF S. A. HAUFFE 《Journal of veterinary pharmacology and therapeutics》1994,17(3):186-192
A high-performance liquid chromatographic method for the determination of the non-steroidal anti-inflammatory drug, oxindanac, in calf plasma is described. Recoveries over the concentration range 0.3 75 to 62.5 μg/ml were 90.2–107.8% with interassay coefficients of variation of 2.1–22.3%. The limit of detection was estimated as 0.10 μg/ml and the limit of quantification calculated to be 0.24 pg/ml in a 1 ml plasma sample. This method was used to establish the pharmacokinetics following intravenous (i.v.), intramuscular (i.m.) and oral (p.o.) administration to calves of oxindanac at a dose rate of 2 mg/kg. The elimination t 1 /2 , was long ( t 1/2 21.2 h after i.v. injection) and absorption was rapid (t1 /2B 0.072 h) and complete ( F > 100%) following i.m. administration. Bioavailability was incomplete ( F = 66.6%) following p.o. administration to calves that had been fed on milk, and Wagner-Nelson analysis revealed twoabsorption phases ( t 1 /2 's 0.20 and 1.9 h). Oxindanac produced long-lasting inhibition of serum TxB2 production, with mean kmax values (% inhibition) of 96.8, 94.1 and 81.3 following i.v., i.m. and p.0. administration, respectively. A single i.v. or i.m. injection of 2 mg/kg oxindanac will probably be active in calves for at least 36–48 h. 相似文献
38.
研究阳际峰自然保护区不同海拔梯度土壤剖面状况及其微生物学性状,探讨土壤微生物量C与N、酶活性、微生物商与呼吸速率的变化及其相互关系。结果发现,不同海拔梯度土壤在微生物学性状上均有较大差异。总的趋势是植被覆盖度高,地形平缓,土层厚,微生物活性强,且与海拔梯度呈显著正相关。在剖面分布上,也有明显的层次差异,即随土层的增加而减少。 相似文献
39.
LE Craig 《New Zealand veterinary journal》2013,61(3)
The morphological characteristics, breed predispositions, site predilections and behaviour of three of the most common types of synovial tumours were discussed. Synovial histiocytic sarcoma represents 50% of synovial tumours, occurring in breeds predisposed to histiocytic sarcoma, and has a poor prognosis. Their histological appearance is similar to histiocytic sarcomas occurring elsewhere. The stifle is the most common site; dogs with ruptured cranial cruciate ligament are predisposed. Synovial cell sarcoma represents 15% of synovial tumours in dogs. They have non-specific spindle cell morphology, and can only be distinguished using cytokeratin immunohistochemistry, which will label a small percentage of the spindle cells. Amputation is often curative, but metastases can occur. Synovial myxoma represents 20% of synovial tumours in dogs. They have a characteristic morphology of myxomatous nodules filling the joint cavity and sometimes extending into the surrounding tissues, including bone. Labrador Retrievers and Doberman Pinschers are predisposed, and the stifle and digit are the most common sites. Prognosis is good; even with incomplete excision some dogs survive years without progression or metastasis. Histopathological examination of synovial tumours is essential to determine the course of treatment, and prognosis. 相似文献
40.
滑皮金柑是融安金柑的实生变异品种,为探明其品质特性,本研究以融安金柑为对照,比较二者果实外观、风味和营养成分的差异。结果表明,滑皮金柑单果质量、纵横径、果皮油胞数和色泽CCI值均显著低于融安金柑。滑皮金柑果实剪切力较低,其他质构指标均显著高于对照。糖酸含量分析表明:滑皮金柑果皮和果肉中葡萄糖、果糖、蔗糖以及总糖含量均显著高于融安金柑;滑皮金柑果皮中柠檬酸和苹果酸含量显著低于对照,而乙酸、马来酸和富马酸含量则显著高于对照;在果肉中,滑皮金柑的柠檬酸和丁二酸含量显著低于对照,而酒石酸、草酸、乙酸、马来酸、富马酸含量均显著高于对照。此外,滑皮金柑果皮和果肉中VC含量相对较低,但总多酚和总黄酮含量显著高于对照。同时滑皮金柑中积累了更多香豆酸和阿魏酸,总酚酸含量也高于对照。 相似文献