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71.
Summary The incorporation of C14-amino acids (aspartic acid, glutamic acid, threonine and proline) and C14-nucleic acid bases (adenine, guanine, cytosine and uracil) into the seedling, reproductive stage and young ear portion of
rice plant was investigated.
It was found that C14-aspartic acid was incorporated into the rice seedling more rapidly than C14-threonine or C14-proline; on the other hand C14-proline was found to be more rapidly incorporated than C14-aspartic acid into reproductive stage plant and young ear portion.
Similarly C14-adenine was incorporated into the rice seedling more rapidly than other C14-labelled bases. On the other hand C14-uracil was preferentially incorporated to C14-adenine or C14-guanine into the reproductive stage plant and young ear portion.
It is suggested from the results obtained that proline is polymerized into polypeptide or protein in the rice plant more rapidly
at the reproductive stage than at the seedling stage and that a higher proportion of pyrimidine bases might be involved into
the metabolic process at the reproductive stage of rice plant. 相似文献
72.
73.
A vitamin B12-producing and hydrocarbon-utilizing bacterium, Corynebacterium simplex, accumulated an appreciable amount of cobalt-porphyrin in cultural filtrates when grown on a n-hexadecane medium containing sufficient amounts of cobaltous sulfate and an appropriate detergent. When grown without the detergent, the cobalt-porphyrin was found only in the cells of the organism. In the latter case, the content of cobalt-porphyrin was comparable to that of vitamin B12 and 7 times lower than that of iron-porphyrin. Though the organism required cobaltous sulfate for optimal growth, the requirement could be efficiently replaced by the supplementation of cobalt-porphyrin and partly of vitamin B12. The porphyrin moieties of extra- and intracellular cobalt-porphyrin were identified as coproporphyrin III in both cases. 相似文献
74.
Inhibitor of pyrimidine metabolism from tumor tissues 总被引:1,自引:0,他引:1
Inhibitors of normal rat liver 5′-nucleotidase and dUMP kinase were found in rapidly proliferating tissues, such as Yoshida sarcoma. Two inhibitors were separated from Yoshida sarcoma by zone electrophoresis, gel filtration on Sephadex G-200 and DEAE-cellulose column chromatography. One inhibited both 5′-nucleotidase and dUMP kinase, while the other inhibited only dUMP kinase. These inhibitors were not detectable in normal rat liver. They were induced in regenerating rat liver and present in rapidly proliferating tissues, such as Yoshida sarcoma and Ehrlich ascites tumor and rat marrow cells. These inhibitors were heat labile. One had a large molecular weight (500,000>) and the other a small molecular weight ( 50,000). 相似文献
75.
76.
Summary The effect of competition pressure on the sequential pattern of adult emergence was studied by using the experimental population
of the azuki bean weevil. The density and pattern of emergence curves of the parental adult induced the changes in the shape
of emergence curve of the progeny as well as the number of progeny individuals. In order to explain these changes, a simple
mathematical model which has two independent variables, the population density and the capacity of environment, was introduced.
The model generated basically similar patterns of emergene curves as observed in the present experiments. This means that
the model displayed well the competition pressure which differentially acted upon early-born and late-born individuals in
the populations being at different densities and which were differentially received by individual progeny according to the
sequential distributions of parents. This different severity of competition pressure resulted in the difference of time when
the pressure compelled influences on the sequential distribution of adult emergence. Therefore, early developed individuals
may have good chance to survive, but the competition pressure works as a factor modifying their fundamental superiority, especially
in the scramble type of competition.
Intense crowding of the azuki bean weevil gave rise to the scramble type of competition in the relation between the numbers
of adults emerged in two successive generations. When parental emergence concentrated in a short term and at high density,
the competition becomes intense, resulting in the inferiority of early developed individuals, in the decrease in number at
the next generation and in the increase of duration for emergence. 相似文献
77.
Lipase and esterase in adipose tissue and liver 总被引:1,自引:0,他引:1
78.
Koichi Fujii 《Population Ecology》1965,7(2):118-125
- A theoretical model for the competition curve, which stands on a few simple assumptions, was proposed.
- Some applications were done to actual data, and during these applications the validity of the present model and its assumptions was discussed.
- From the present model it can be expected that there is a discrete competition mechanism even in the appearently continuous medium.
79.
Koichi Fujii 《Population Ecology》1965,7(1):43-51
Experimental studies was made on the interspecies competition between the azuki bean weevil, Callosobruchus chinensis and the southern cowpea weevil, C. macultatus. And the following results were obtained.
- The reverse result of competition between the two species observed under the air-tight condition and the air-free one. That is, the population of the azuki bean weevils destroyedby that of the southern cowpea weevils under the former condition and vice versa under the latter. It is thought that such a reversal is due to the difference of sensibility of each species to the air-tight condition.
- Under the air-free condition, change of the time interval of food-supplying had no effect on the result of competition within the limits of this experiment. The population of the southern cowpea weevils was always destroyed by that of the azuki bean weevils. But there was a certain degree of correlation between the duration of co-existence and the interval of food-supplying.
- From the results, it is possible to say that by changing the degree of air-tightness, or the time interval of food-supplying, the co-existence period and the final result of competition can be changed.
- The different mechanism of competition between two species in the present experiment from the experiments ofUtida (1952) andYoshida (1957) were discussed.
- A difference in the mechanism of interspecies competition and intraspecies competition was expected from the level of total population numbers of two species and the individual weight of C. chinensis.
80.
Hisashi Miyazaki Masatoshi Iida Yoshimasa Matsunaga Toshihiko Fujii Keiko Nambu Hideki Amejima Yoshinori Oh-e Hideo Furukawa Yukiharu Matsui Yasunobu Sohmura Masahisa Hashimoto 《Biotherapy》1989,1(1-2):47-57
The mode of antitumor action of rHu-TNF was elucidated in BALB/c mice bearing Meth A fibrosarcoma 7 days after transplantation with respect to time course, dose-response relationships and selectivity of the effects. The maximal cytotoxic effect on tumor cells revealed by inhibition of DNA synthesis and maximal lesional effect on tumor vasculature revealed by change in blood pool-size in the tissue were detected at 30 min and I h after administration of rHu-TNF, respectively. The dose-response relationship between cytotoxic and tumoricidal effects of rHu-TNF was irrespective of administration route. ED50s of these antitumor effects afteri.v. administration of rHu-TNF were about 50 times as high as ED50s afteri.t. administration. ED50 ofi.t. given rHu-TNF for vascular effect was about 20 times as high as that for cytotoxicity while ED50 ofi.v. rHu-TNF for vascular effect was only 2–3 times as high as that for cytotoxicity. The whole body autoradiographies with [125I] HSA giveni.v. to see the blood influx into tumor tissue and [14C]thymidine given i.v. to see DNA synthesis in the whole body after administration of rHu-TNF revealed that the distribution of radioactivity was markedly changed in the tumor alone without any detectable change in other whole body tissues.In conclusion, thein vivo antitumor effect of rHu-TNF giveni.t. ori.v., appears to be exerted through the direct action on Meth A sarcoma rather than indirectly on tumor vasculature. Under present conditions, the effect of rHu-TNF in the whole body tissues seems rather selective on cells and vasculature of the tumor. 相似文献