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21.
Ken Thompson 《Journal of Biogeography》2003,30(1):155-156
22.
23.
Ogawa Masahiro; Kumamaru Toshihiro; Satoh Hikaru; Iwata Nobuo; Omura Takeshi; Kasai Zenzaburo; Tanaka Kunisuke 《Plant & cell physiology》1987,28(8):1517-1527
Protein body type one (PB-I) was isolated and purified fromdeveloping rice grain by a combination of sucrose density gradientcentrifugation and treatment with pepsin. SDS-PAGE analysisshowed that isolated PB-I contains several polypeptide groups,the largest having an apparent molecular size of 13 kDa andtwo smaller ones of 10 kDa and 16 kDa. The 13-kDa group wasfound to be composed of two polypeptides of slightly differentmolecular sizes, 13a (larger component) and 13b (smaller component).Most of the 13a and 13b polypeptides were shown to be largelyprolamins, although there were also some salt- and alcohol-insolublepolypeptides with an apparent molecular size of 13 kDa. It wasconcluded that PB-I is the accumulation site of rice prolamin.It was further estimated that the protein amount in PB-I accountedfor about 20% of the total protein of rice endosperm. (Received March 20, 1987; Accepted September 8, 1987) 相似文献
24.
Summary The antimetastatic effect of Lactobacillus casei YIT9018 (LC 9018) against Lewis lung carcinoma (3LL) in C57BL/6 mice was determined. Intrapleural (i.pl.) administration of LC 9018 was effective in inhibiting pulmonary metastasis after s.c. inoculation of 3LL tumors into C57BL/6 mice. The combination of i.pl. and intralesional or i.v. injections of LC 9018 also markedly inhibited pulmonary metastasis in 3LL-bearing mice. The i.pl. administration of LC 9018 into mice induced an increase in the number of thoracic exudate cells (TEC) and the cell population in the TEC was mainly polymorphonuclear leukocytes in the early stage, while macrophages were dominant in the late stage. In addition, in vitro cytolytic activity against 3LL cells and natural killer cell activity of TEC were augmented by the i.pl. administration of LC 9018. Furthermore, i.pl. administration of LC 9018 into the mice rendered their lung macrophages tumoricidal for 3LL cells in vitro. These results show that TEC induced by i.pl. administration of LC 9018 played a key role in the inhibtion of metastasis in 3LL-bearing mice. 相似文献
25.
Ken B. Waites Joseph G. Tully David L. Rose Peggy A. Marriott Richard O. Davis Dr. Gail H. Cassell 《Current microbiology》1987,15(6):325-327
Acholeplasmas have been isolated from a variety of animals, insects, and plants, but onlyAcholeplasma laidlawii has previously been found in humans. We have isolatedAcholeplasma oculi in pure culture from the amniotic fluid of a woman at 19 weeks of gestation. The organism was positively identified by growth inhibition, epi-immunofluorescence, and arbutin hydrolysis. Demonstration of organisms directly in amniotic fluid by DNA fluorochrome and immunofluorescence staining provided additional evidence that the isolate was genuine and not a medium contaminant. The remainder of the pregnancy was unremarkable, and a full-term male infant was delivered without complications. Even though there is some evidence possibly associatingA. oculi with various diseases in livestock, the prevalence and significance ofA. oculi in humans has not been determined. 相似文献
26.
Hydrogen Peroxide-dependent Synthesis of Flavonols in Mesophyll Cells of Vicia faba L. 总被引:2,自引:0,他引:2
Mesophyll cells of Vicia faba contain kaempferol and quercetinglycosides. When isolated mesophyll cells were treated with0.1 mM H2O2 for 2 h, the levels of these flavonols increasedby 1070% of the control values (mean values, 19.6% and34.4% for kaempferol and quercetin glycosides, respectively).Such increases in levels of flavonols were also observed inisolated vacuoles of mesophyll cells. However, when mesophyllcells and vacuoles were treated with 10 mM H2O2)degradationof flavonols was observed. These data suggest that H2O2 hastwo effects on the metabolism of flavonols: induction of theirsynthesis and stimulation of their oxidation. (Received March 6, 1989; Accepted July 10, 1989) 相似文献
27.
Ken S. Dhalla Pallab K. Ganguly Heinz Rupp Robert E. Beamish Naranjan S. Dhalla 《Molecular and cellular biochemistry》1989,87(1):85-92
Using the reverse phase high-performance liquid chromatography (HPLC) with mobile phases composed of simple acids, we have developed an assay technique for the measurement of adrenolutin, one of the oxidation products of catecholamines, in rat plasma. Ion-pairing chromatography permits the separation and quantitation of plasma adrenolutin (M) in a linear manner. Sample preparation involved the precipitation of plasma proteins with perchloric acid and it is easier to handle a large number of samples at a time. However, we were unable to demonstrate the presence of adrenochrome, another oxidation product of catecholamines, in plasma since adrenochrome was rapidly destroyed in acid as well as in blood and was quickly changed, into adrenolutin. Adrenolutin peak in HPLC was confirmed by 1) the retention time; 2) co-injection of adrenolutin and; 3) the appearance of 3H-adrenolutin after injection of 3H-norepinephrine. Administration of different catecholamines as well as adrenochrome and adrenolutin in rats also increased the level of adrenolutin in plasma. Adrenolutin was found to be present in plasma in other species including dog, rabbit and pig. High level of adrenolutin, which may represent total concentration of aminolutin in plasma, suggests the presence of an efficient mechanism for the oxidation of catecholamines under in vivo conditions. 相似文献
28.
Osamu Kondo Hiroyuki Honda Masahito Taya Takeshi Kobayashi 《Applied microbiology and biotechnology》1989,32(3):291-294
Summary Growth properties of carrot hairy root cells in various bioreactors were investigated. A turbine-blade reactor and an immobilized rotating drum reactor were found to be advantageous for the hairy root culture because of a high oxygen transfer coefficient (k in L a). After 30 days of culture, 10 g/l of dry hairy root cells were obtained in both bioreactors and maximum growth rates (V
m
) were found to be 0.63 and 0.61 g/l per day for the turbine-blade reactor and immobilized rotating drum reactor, respectively. Specific growth rates () at various cultivation times were observed to be linearly proportional to X/k
l
a for both bioreactor configurations where X is the cell concentration. The estimated specific oxygen uptake rate of 0.34 mmol O2/g dry cells per hour compares fairly well with an experimental value of 0.3. 相似文献
29.
Twelve polyether compounds originating from dinoflagellates were tested for growth-inhibiting activities againstAspergillus niger, Penicillium funiculosum, Candida rugosa, Escherichia coli, Bacillus megaterium andStaphylococcus aureus by a paper disc method. These polyethers represent six groups of different skeletons and originate from three species;Prorocentrum lima, Dinophysis fortii andGambierdiscus toxicus. Potent antifungal activities were observed with okadaic acid and its two congeners, desulfated yessotoxin, and ciguatoxin but not with okadaic acid esters, prorocentrolide, pectenotoxin-1, yessotoxin, maitotoxin, and desulphated maitotoxin. The antifungal activities and mouse lethalities of the polyethers were markedly affected by slight modification of their structures. Antibacterial potency of the tested compounds was not significant. 相似文献
30.
A method is proposed for predicting the adjacency order in which strands pack in a -sheet in a protein, on the basis of its amino acid sequence alone. The method is based on the construction of a predicted contact map for the protein, in which the probability that various residue pairs are close to each other is computed from statistically determined average distances of residue pairs in globular proteins of known structure. Compact regions, i.e., portions of the sequence with many interresidue contacts, are determined on the map by using an objective search procedure. The proximity of strands in a -sheet is predicted from the density of contacts in compact regions associated with each pair of strands. The most probable -sheet structures are those with the highest density of contacts. The method has been tested by computing the probable strand arrangements in a five-strand -sheet in five proteins or protein domains, containing 62–138 residues. Of the theoretically possible 60 strand arrangements, the method selects two to eight arrangements as most probable; i.e., it leads to a large reduction in the number of possibilities. The native strand arrangement is among those predicted for three of the five proteins. For the other two, it would be included in the prediction by a slight relaxation of the cutoff criteria used to analyze the density of contacts. 相似文献