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91.
Microbial mineralization of organic phosphate in soil   总被引:35,自引:0,他引:35  
Summary Phosphate-dissolving microorganisms were isolated from non-rhizosphere and rhizosphere of plants. These isolates included bacteria, fungi and actinomycetes. In broth cultures, Gram-negative short rod,Bacillus andStreptomyces species were found to be more active in solubilizing phosphate thanAspergillus, Penicillium, Proteus, Serratia, Pseudomonas andMicrococcus spp. The sterile soils mixed with isolated pure culture showed slower mineralization of organic phosphate than that of non-sterile soil samples at all incubation periods. Maximum amount of phosphate mineralization by isolated microorganisms were obtained at the 60th and the 75th day of incubation in sterile and non-sterile soils respectively. The mixed cultures were most effective in mineralizing organic phosphate and individuallyBacillus sp. could be ranked next to mixed cultures. Species ofPseudomonas andMicrococcus were almost the same as that of the control under both sterile and non-sterile conditions.  相似文献   
92.
In rats grown up in small and large nests the lipolytic activity of adipose tissue was studied in vitro in dependence on age. Independent of age and sex a significantly higher lipoprotein lipase activity as well as a lower basal or norepinephrine stimulated lipolysis and reesterification (absolute) occurred in rats from small nests compared with rats from large nests. The calculated degree of reesterification was independent of the nest size, but decreased from 80% to 30% from one month to one year of age. The marked differences in the lipolytic activities of adipose tissue emphasize the distinct influence of the post-natal nutrition on metabolic functions in the later life and lead to the conclusion that the metabolism of adipose tissue of animals from small nests is directed towards a long-term increased storage of lipids.  相似文献   
93.
Summary The effect of growth at 30°, 35° and 40° on the biomass yield and on the nucleic acid and protein content of twelve isolates of yeast has been studied. Although yields of 41.6% and a true protein content of 34% were obtained, each of the strains exhibited a lower yield and protein content at 40° than at the lower temperatures. Nucleic acid levels were also reduced at 40°.  相似文献   
94.
A total of 292 randomly selected subjects belonging to two indigenous Arab tribes (Harbi and Ghamid) and two immigrant tribes (Mograbi and Mowallad), residents in Western Saudi Arabia, have been tested for genetic variants of six blood groups, four serum proteins, and five red cell enzyme systems. The distribution of the polymorphic systems was different between indigenous and immigrant tribes, and the present Arab population shows a considerable degree of admixture from the surrounding countries, in particular Africa.  相似文献   
95.
Spore suspensions from 7 day old cultures of Curvularia lunata (Wakker) Boedijn var. aeria (Batista, Lima and Vasconcelos) M.B. Ellis were added to soil samples originally devoid of Curvularia propagules. The test fungus disappeared after six weeks of inoculation irrespective of soil amendments, like the application of green manure, urea, superphosphate, or soil cropped to Sorghum (dura) or cotton seedlings.  相似文献   
96.
A population of Solea vulgaris was transplanted in 1938 from the Mediterranean to a land locked brackish lake. In 1977, the morphology of these fishes was investigated and a number of measurements made and compared with those of fish caught in the Mediterranean. Among these variations was less vertebrae and fewer dorsal fin rays in the lake soles.  相似文献   
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99.
In the hyphae of Penicillium cyclopium the in vitro measurable activities of 3 enzymes of alkaloid biosynthesis are induced endogenously during  相似文献   
100.
The sensory innervation of the small intestine was studied in the cat with electrophysiological, histological and histochemical techniques. Thanks to the histochemical technique (peroxydase method) the exact number and proportion of splanchnic and vagal fibres was determined : the latter being about 9 times more numerous than the former. On the other hand the exact position of the corresponding cells was defined in the nodose and spinal ganglia by means of the previous technique and the microelectrophysiological method (recording of single units into the ganglia with extracellular glass microelectrodes). The splanchnic neurones were found in the T9, T10 and T11 ganglia whereas the vagal ones were chiefly located in the lower half of the nodose ganglia. The histological studies using electronic microscope showed many non-medullated endings, which were often found beneath the epithelium and in the lamina propria of the villi close to the blood vessels. This result is certainly the proof that numerous receptors (mechanoreceptors, chemoreceptors and even thermoreceptors do exist in the small intestine.  相似文献   
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