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171.
Energy utilization for polysaccharide synthesis by mixed rumen organisms fermenting soluble carbohydrates 总被引:3,自引:2,他引:1 下载免费PDF全文
Walker DJ 《Applied microbiology》1968,16(11):1672-1677
Synthesis of reserve polysaccharide by mixed rumen organisms fermenting glucose, maltose, cellobiose, and xylose has been studied in relation to the adenosine triphosphate energy calculated to be available from substrate fermentation. About 80% of the energy available from glucose and xylose was used for polysaccharide synthesis, whereas, assuming hydrolytic cleavage of the disaccharides, more than 100% was used when cellobiose and maltose were the substrates. If, however, phosphorolytic cleavage of the disaccharides, for which there is evidence, was involved, the energy from both maltose and cellobiose fermentation was used with about the same efficiency as that from glucose and xylose fermentation. The rumen fluid used was collected 24 hr after feeding, and growth of microorganisms in such samples was sufficient to account for utilization of less than 10% of the total energy becoming available during the 40-min incubation period. 相似文献
172.
Blood pressure within the corpus cavernosum penis of the bull 总被引:1,自引:0,他引:1
J E Lewis D F Walker S D Beckett R I Vachon 《Journal of reproduction and fertility》1968,17(1):155-156
173.
Value of field data for extrapolation in anthrax 总被引:8,自引:0,他引:8
174.
Pathophysiological and biochemical changes in anthrax 总被引:4,自引:0,他引:4
175.
176.
Jerry S. Walker Frederick Klein Ralph E. Lincoln Albert L. Fernelius 《Journal of bacteriology》1967,94(3):552-556
Rats, rabbits, swine, guinea pigs, and monkeys were infected with anthrax spores, and their temperature responses were recorded. These were characteristic for a species and appeared independent of resistance or susceptibility of the species toward establishment of the disease. The rabbit appeared unique in that it not only failed to demonstrate a dose-response relationship over an 8-log dose range, but acted independently producing erratic body temperatures depending on spore dose. This limits the usefulness of the rabbit in studying anthrax pathogenesis, and poses questions regarding published data with the rabbit as the test animal. 相似文献
177.
178.
Vascular responses to venous congestion 总被引:4,自引:0,他引:4
179.
1. Feeding a high-glucose diet to weanling rats showed that high hepatic glucokinase activities could be induced at 18 days of age, i.e. 2 days after development of the enzyme begins. 2. The normal development of glucokinase activity can be retarded by weaning rats on to carbohydrate-free, high-fat and high-protein diets. 3. Precocious development of the enzyme before 16 days of age cannot be induced by oral glucose administration. 4. It is concluded that the ability to synthesize glucokinase develops very rapidly and that the nature of the diet determines the normal developmental pattern. 相似文献
180.