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Milk somatic cell counting was carried out by Fossomatic and microscopically. In unpreserved milk samples Fossomatic counts increased by up to 100% during the first 24 hours after milking. During the next 24 hours the counts increased by 5% whereafter they remained stable until at least 80 hours after milking, when the samples were stored at 5 degress C. On microscopical counting using methylene blue for staining, the results were stable from shortly after milking. In counting, attention had to be paid to the fact that within the first 24 hours a certain part of the cells would stain but faintly. After preservation with potassium bichromate the Fossomatic counts increased more rapidly. Stable results were found 5--8 hours after preservation. The final level of the Fossomatic counts was found to be app. 10% higher in preserved than in unpreserved samples. A smaller increase was found by microscopic counting. The rise of the cell counts during the first 24 hours after milking is probably due to inadequate stainability of living cells with ethidium bromide, resulting in a certain part of them being recorded by the Fossomatic. During the first day the vitality of the cells diminishes whereby they become stainable and countable. This process in hastened by potassium bichromate treatment.  相似文献   
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Internal derangements in the human knee joint caused by meniscal lesions affecting joint function are known to have influence on local radionuclide uptake (Nicholas & Holder 1980, Mooar et al. 1987). To elucidate the joint reaction to minor meniscal lesions, not interfering with knee joint function, a model involving the avascular central part of the medial meniscus was used. Lesions in this area are known not to heal spontaneously (Heatley 1980, Veth et al. 1983).  相似文献   
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Coesite, the high-pressure polymorph of SiO(2), hitherto known only as a synthetic compound, is identified as an abundant mineral in sheared Coconino sandstone at Meteor Crater, Arizona. This natural occurrence has important bearing on the recognition of meteorite impact craters in quartz-bearing geologic formations.  相似文献   
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Summary The levels of starch phosphorylation in potato tubers were investigated in relation to fertilization with phosphorus (P) of field-grown and greenhouse-grown plants. The field-grown plants received 0, 15 or 30 kg P ha−1. Starch from plants grown without P-fertilizer contained 15.6 nmol P (mg starch)−1 whereas starch from plants grown with 30 kg P ha−1 contained 20.6 nmol P (mg starch)−1. The greenhouse-grown plants were cultured in inert media and received nutrient solutions containing 0, 3, 12 or 24 mg P l−1, respectively. Plants grown with no P-fertilizer produced tuber starch with phosphorylation levels reduced to approximately 30% of the level found in plants grown with an ample supply of P. Thus, the level of starch phosphorylation can be modified by limiting the P-supply through the root system. Application of foliar P-fertilizer to the greenhouse-grown plants had no significant effect on the phosphorylation of the tuber starch.  相似文献   
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主要微量元素的功用 微量元素如何调节动物的机体代谢,在许多方面尚不清楚,以下是我们已经了解到的部分内容,但什么是生长或繁殖的 最佳需要量,哪种化学结合最易被动物吸收利用,至今只有有限的研究资料,这为我们的生产带来许多不确定因素。特别 是重金属铜超量不仅能引发动物自身的毒害作用,同时还会造成严重的环境污染,甚至是肉品自身的污染。有限的研究资 料显示,微量元素的利用对动物健康作用显著,选择正确与否将对动物的繁殖性能及生长性能有显著的影响。  相似文献   
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