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51.
The natural 13C abundance (13C value) of the field-grown leguminousplants (soybean, kidney bean, pea, azuki bean, mung bean, peanutand cowpea) was investigated by mass spectrometry with a precisionbetter than %0.2 for 13C. Among organs of premature plants,the leaves had the most negative values, and the nodules generallyhad the least negative values, and other organs, fruits, stemsand roots, showed intermediate values. In the soybeans so farinvestigated, the grains of nodulating plants exhibited higher13C values than nonnodulating lines. The 13C values of the grainsvaried depending on the species: peanuts showed the most negativevalues. Possible causes underlying these variations are discussed.
3Institute of Biological Sciences, University of Tsukuba, Sakura-mura,Ibaraki 305, Japan. (Received December 3, 1982; Accepted May 25, 1983) 相似文献
52.
Interindividual distance and influence of dominance on feeding in a natural Japanese macaque troop 总被引:5,自引:0,他引:5
Takeshi Furuichi 《Primates; journal of primatology》1983,24(4):445-455
In a natural troop of Japanese macaques (Macaca fuscata yakui), the dominant-subordinate relationship restricted the feeding behavior of the subordinate in two ways: (1) the dominant
drives away the subordinate through agonistic interactions; and (2) the subordinate avoids approaching the dominant without
any agonistic interactions. These occurred only infrequently, and only when an interindividual distance was less than a certain
distance, which is called the “tolerance/intolerance” (T/I) distance. On the other hand, the usual interindividual distance
when feeding was much greater than the T/I distance. Therefore dominance has little influence on feeding in the study troop.
In the study troop, the T/I distance between kin-related females was shorter than that between unrelated individuals. Although
this difference may facilitate kin selection if the troop faces severe competition over concentrated food, the difference
does not seem to influence survival or reproductive rate in the study troop. 相似文献
53.
Two adenosine 3',5'-cyclic monophosphate (AMP)-deficient mutants of Vibrio cholerae (biotype El Tor) were successfully isolated by nitrosoguanidine treatment followed by pencillin screening for pleiotropic sugar-negative clones. Exogenous cyclic AMP is required for the fermentation of sucrose, trehalose, fructose, maltose, and mannose but not of glucose, as well as for the formation of normal flagella and specific somatic antigens. A striking characteristic of the mutants is their growth behavior at higher temperatures. They cannot grow on TCBS selective plates at 37 C or higher unless they are provided with a supply of exogenous cyclic AMP, although they are capable of producing colonies on the same medium, even without cyclic AMP, at temperatures lower than 30 C. Since the mutants are converted to spheroplasts, spindle forms, and spiral filaments in cyclic AMP-free media at 37 C, and this phenomenon is stopped by the addition of cyclic AMP or a combination of 20% sucrose and 0.2% magnesium chloride, it is assumed that cyclic AMP is essential for the synthesis of the cell wall of V. cholerae at higher temperatures. 相似文献
54.
Mutants of Group D1Salmonella Carrying the Somatic Antigen of Group A Organisms: Isolation and Serological Characterization 总被引:2,自引:2,他引:0
O antigen mutants were obtained from Salmonella durban, a group D(1) organism, by treatment with N-methyl-N'-nitro-N-nitrosoguanidine. Serological studies demonstrated that the mutants lost the O-9 antigen factor of the parent organism but acquired the O-2 factor specific to group A Salmonella. Lipopolysaccharides of the mutant strains contained paratose which determines the specificity of O-2 factor. Tyvelose, present in the wild-type lipopolysaccharide, was not found in the mutants. H antigens and other biological characteristics of the mutant strains were the same as those of the wild-type organism. The present finding implies that group A Salmonella species might be derived from group D(1) organisms. 相似文献
55.
56.
Nonselective Incorporation into Sporangium of Either “Older” or “Younger” Chromosome of the Vegetative Cell During Sporulation in Bacillus cereus
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Employing Bacillus cereus strain 2, we examined the fate of two chromosomes contained in vegetative cells in the course of sporulation. Cytological observations and quantitative estimation of deoxyribonucleic acid (DNA) confirmed the earlier observations that, during the course of sporulation, one of two chromosomes of the vegetative cell was incorporated into the sporangium and the other disappeared into the medium as the result of cell lysis. Log-phase cells, labeled completely with thymine-2-(14)C in the presence of deoxyadenosine, were cultured in the "cold" glucose-glutamate-glycine-salts medium, and culture samples, taken at intervals at successive generations, were subjected to sporulation in glutamate-salts medium. The percentage of radioactivity in the spores separated from each culture remained almost unchanged at nearly 50% and was independent of the number of generations of the preceding culture in the "cold" medium. This suggests that the selective incorporation into the sporangium of either the "older" or "younger" chromosome of a vegetative cell does not occur in the course of spore formation. Some examples of the selective and nonselective behavior of DNA molecules in cellular events in microorganisms are cited. 相似文献
57.
58.
59.
Isolated microspores of Chinese cabbage (Brassica campestris ssp. pekinensis) were incubated in modified NN medium containing 10% sucrose in darkness at 33°C for one day followed by culture at 25°C. After 14 days of culture, microspores developed into embryos ranging from globular to cotyledonary stage. Plants were regenerated after transfer of embryos to medium containing 3% sucrose and no plant growth regulators.Abbreviations NN
Nitsch and Nitsch
- MS
Murashige and Skoog
- NAA
naphthaleneacetic acid
- BA
6-benzylaminopurine 相似文献
60.
Noriaki Inamura Saburo Sone Akio Okubo Eiji Kunishige Mie Nakanishi Takeshi Ogura 《Cancer immunology, immunotherapy : CII》1989,28(3):164-170
Summary Human blood monocytes were isolated by counter-flow centrifugal elutriation from healthy donors and these noncytotoxic monocytes were rendered tumoricidal to allogeneic melanoma (A375) cells by activation with a synthetic acyltripeptide (FK-565), as assessed by measuring release of [125I]iododeoxyuridine in 72 h. When monocytes were treated with FK-565 for 16 h, and then fixed with paraformaldehyde, they showed cytotoxicity to A375 melanoma cells. The fixed-monocyte-mediated cytotoxicity to A375 cells was induced by the synergistic actions of FK-565 and recombinant interferon- (rIFN-), but not other cytokines [rIFN-A, rIFN-, tumor necrosis factor (TNF), interleukin (IL)-2, -3 and -6]. For synergistic activation of monocytes with induction of a membrane-associated antitumor monokine, the monocytes had to be incubated first with rIFN- and then with FK-565. FK-565 also acted synergistically with rIFN- to stimulate monocytes to produce membrane-associated IL-1 activity, which induced C3H/HeJ thymocyte blastogenesis in response to phytohemagglutinin P. The tumoricidal and thymocytestimulating activities of the fixed monocytes were almost completely inhibited by a specific anti-(IL-1) antiserum, but not by a specific anti-(IL-1) antiserum or monoclonal anti-TNF antibody. These results suggest that membrane-associated IL-1 of human blood monocytes can be induced by two activation signals (rIFN- then FK-565) at their suboptimal concentrations.Abbreviations IL
interleukin
- IFN
interferon
- TNF
tumor necrosis factor 相似文献