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31.
A gas chromatographic method was developed for the determination of monoacetylputrescine, monoacetylcadaverine, N1-acetylspermidine and N5-acetylspermidine in human urine. The amines were isolated from urine by silica gel column chromatography. 1, 10-Diaminodecane was used as internal standard. The amines were reacted with ethyl chloroformate in aqueous medium to four ethyloxycarbonyl derivatives prior to application to gas chromatography using a flame ionization detector. Separation and determination of the derivatives were carried out on a Uniport HP column (1.0 m) impregnated with 0.5% SP-1000 under temperature-programmed conditions. The monoacetylpolyamines could be measured accurately at the nanomole level. The method was used for the determination of the monoacetylpolyamines in urine of healthy volunteers. The values obtained were in the range of the published data.  相似文献   
32.
The accumulation pattern of arachin and its subunits in growinggroundnuts was investigated. Soluble proteins were extractedfrom the kernels at twelve different stages of maturation (4–16weeks after pegging). Fractionation showed arachin, conarachinII, 5S and 2S protein components with sucrose gradient centrifugation.Ten weeks after pegging, only 35% of the maximum amount of arachinhad accumulated, whereas conarachin II was 85%, the 5S component89%, and the 2S component 76%. Arachin, however, increased rapidlyin the later stage of maturation. No change in the subunit ratioin arachin during seed growth was observed on the patterns ofsodium dodecyl sulfate-gel electrophoresis and gel isoelectricfocusing in the presence of urea. The ratio of the arachin subunitscontained in urea-extractable fraction of the kernels was constantthroughout seed development and was consistent with the subunitratio in arachin. On the other hand, the arachin subunits inthe free forms, if any, accounted for less than 1% of the associatedarachin subunits. Probably, the arachin subunits synthesizedin equimoles are associated into arachin without individualdeposition and are accumulated as arachin associates in growingseeds. (Received July 17, 1980; )  相似文献   
33.
The possible role of sophorolipids from Torulopsis bombicola was investigated in alkane fermentation. Sophorolipids and related model compounds specifically stimulated the growth of strains of Torulopsis yeasts on insoluble alkanes and may act as a specific growth factor. There may be more than one way for a yeast to be stimulated to incorporate alkanes for growth.  相似文献   
34.
A factor that stimulates purified DNA polymerase β about 2-fold was separated from DNA polymerase β activity on a DNA-cellulose column. During the early stage of purification, the factor may be associated with DNA polymerase β to form a complex that sediments at 3.9 S in sucrose gradients and behaved as a 52,000 dalton protein on a Sephadex G-100 column. The complex, which contains 40,000 and 12,500 dalton polypeptides, was insensible to the stimulator, and did not show any exonuclease activity.  相似文献   
35.
The performance of fluidized-bed reactors utilizing a magnetic field was determined by the use of magnetite-containing beads of immobilized unease. The reactors showed similar or higher conversions in comparison with fixed-bed reactors, although some aggregation of the beads in the magnetic field was observed. No effusion of the beads occurred up to a flow rate of 24 cm/min.  相似文献   
36.
Performance of affinity chromatography columns was studied by measuring the rates of adsorption and elution of trypsin in a Sepharose 4B-soybean trypsin inhibitor column and a Sepharose 4B-arginine peptides column. The volumetric coefficient for trypsin transfer was evaluated from the break-through curves of trypsin, and elution profiles bed height of Sepharose 4B-STI column was estimated based on these results.  相似文献   
37.
The neutral component of d-mannan of bakers' yeast (Saccharomyces cerevisiae), consisting solely of d-mannose residues, was precipitated with concanavalin A to give four fractions. The first three displayed similar reactivities in quantitative precipitin reaction against concanavalin A and homologous anti-S. cerevisiae serum, but the fourth showed different precipitin curves. Analysis of the fractions by acetolysis indicated structural differences. The different behavior of the last fraction in precipitin reactions could be due to a lower content of branching points, or to shorter chain-lengths.  相似文献   
38.
39.
 It is known that the retina contains the protein dystrophin in the ribbon synapse, but the ultrastructural analysis is not yet fully elucidated. Our previous study reported that dystrophin is localized under the rod cell membranes in rat retinas. In the present study, we have investigated the relationship between dystrophin-rich regions of rod cell membranes and other neuronal processes in mouse retinas with a monoclonal antibody raised against the human dystrophin C-terminus. Immunoblotting, immunofluorescence stainings, and immunoelectron microscopy were employed. Immunoblotting analysis indicated that mouse retinas possessed some of the dystrophin isoforms of approximately 260 kDa, 140 kDa, and 70 kDa molecular weight. Confocal images showed a punctate appearance in the outer plexiform layer, as previously described. Immunoelectron microscopy showed that dystrophin immunoreactive products were always observed at submembranous dense regions of the rod spherule abutting bipolar processes. These results suggest that retinal dystrophin may be closely involved in signal transmission from rods to bipolar cells. Accepted: 7 May 1997  相似文献   
40.
Since S-n-butyl S′-p-tert-butylbenzyl N-3-pyridyldithiocarbonimidate, a potent fungicide to powdery mildew, is known to inhibit ergosterol biosynthesis in Monilinia fructigena, the activities were assessed on 24 compounds having other substituents than the 3-pyridyl and on 24 compounds having a variety of different structures connecting the 3-pyridyl and the p-tert-butylphenyl group from that of the dithiocarbonimidate.

In the former group the 3-pyridyl group was essential for the activities and the substitution at the 2- or 6-position resulted, on available data, in inactive compounds. Several other β-N-heterocyclic analogs were also active. In the latter group, a number of modified compounds from the dithiocarbonimidate structure were shown to be active.  相似文献   
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