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21.
The gene encoding manganese peroxidase of a white-rot fungus Phanerochaete crassa WD1694 was cloned and sequenced. Four genomic clones were sequenced in which 3 clones were existed as alleles. The analysis of intron–exon structures divided the 4 clones into three subfamilies that corresponded to mnp2 and mnp3 of Phanerochaete chrysosporium, and a new subfamily possessing only five introns. The purified P. crassa WD1694 MnP consisted of 4 isozymes with same molecular weight, same N-terminal sequence, and different pI. N-terminal sequence of deduced protein of P. crassa mnpB3 gene was identical to those of 4 MnP isozymes; however, the other 3 mnp genes had different N-terminal sequence. The molecular weight of encoded mature protein of mnpB3 gene and purified MnP had a gap that could be difference between MnP proteins encoded by single gene. The results suggested that 4 MnP isozymes of P. crassa WD1694 arose from single gene.  相似文献   
22.
Historical control data of tumor incidence were collected from the control groups (215 animals of each sex) in four recent carcinogenicity studies that were started between 2005 to 2009 (terminally sacrificed between 2007 and 2011) at BoZo Research Center Inc. (Gotemba, Shizuoka, Japan) using Fischer 344 rats (F344/DuCrlCrlj). These data were compared to the previous historical control data (from 1990 to 2004, previously reported) in the same facility. In the results, the incidence of C-cell adenoma in the thyroid tended to increase in both sexes in recent years (30.8% for males and 24.4% for females in 2005-2009) as compared with the previous data (17.4% and 20.1% for males and 11.5% and 11.8% for females in 1990–1999 and 2000–2004, respectively). In addition, the incidences of pancreatic islet cell adenoma in males and uterine adenocarcinoma tended to increase from around 2000 and remained high in recent years (incidences of islet cell adenoma in males of 10.5%, 17.1% and 20.5% in 1990–1999, 2000–2004 and 2005–2009; incidences of uterine adenocarcinoma of 3.3%, 12.0% and 13.5% in 1990–1999, 2000–2004 and 2005–2009, respectively). There was no apparent difference in the incidence of other tumors.  相似文献   
23.
When saliva and gastric juice are mixed, salivary nitrite is transformed to nitrous acid to produce nitric oxide (NO). The NO formation in acidified saliva was enhanced by ascorbic acid and chlorogenic acid. Thiocyanate ion (SCN(-)) also enhanced the transformation of nitrous acid to NO. During the NO formation in the presence of both ascorbic acid and chlorogenic acid, ascorbic acid was preferentially oxidized. Chlorogenic acid was oxidized after ascorbic acid had been oxidized. Ascorbyl radical was detected during the oxidation of ascorbic acid, and the radical intensity was decreased by chlorogenic acid. The decrease is discussed to be due to the reduction of the oxidation intermediate or product of chlorogenic acid by ascorbyl radical. The result obtained in this study suggests that ascorbic acid was preferentially oxidized and that not only ascorbic acid but also ascorbyl radical could interact with the oxidation intermediate or product of chlorogenic acid when chlorogenic acid was added to the mixture of saliva and gastric juice that contained ascorbic acid.  相似文献   
24.
Preparation of liquid polyols from d-(+)-glucose (Glc) and its derivative, methyl--d-glucoside (m-Glc), has been studied. Direct reaction of -caprolactone (CL) with Glc (CL:Glc = 2:1–5:1 in weight ratio) at 150°C using tin(II) 2-ethyl hexanoate (SnEht2) (series A), in which melted Glc was suspended in CL, resulted in a dark-brown coloration of the reactants. The reaction was accompanied by formation of high molecular weight resins, a pH drop, production of water, and a considerable decrease in the hydroxyl value from the theoretically expected one. In the case of Glc/ethylene glycol (EG)/CL reaction system with SnEht2 catalyst at 150°C (series B), in which the weight ratio of Glc to EG was fixed at 1:1, Glc dissolved in the EG/CL mixture, but the brown coloration of the reactant mixture still occurred. In this case, the formation of water was enhanced, but the other effects found in series A were suppressed to a considerable extent. In the m-Glc/CL/SnEht2 reaction system (series C), in which m-Glc reacted with two to five times weight amounts of CL under the same conditions adopted in series A, development of the color, the production of high molecular weight materials and water, and the changes in pH and hydroxyl value were not observed. These results are discussed based on the chemical structural differences: Glc exists mostly in the hemiacetal form, but tautomerizes to the aldehyde, whereas m-Glc is an acetal and is protected from reversion to the aldehyde.  相似文献   
25.
To construct a vector for caspase-1 independent expression of canine IL-18, the signal sequence of canine IL-12p40 was fused to the sequence of mature IL-18 on the NdeI restriction site which is located at the 3' end of the signal sequence. The resulting vector expressed coding protein from transfected mammalian cells. The expressed protein was shown to have IL-18 bioactivity in a INF-gamma-inducing assay. These results suggest that the expression vector is the desired tool for advancement of dendritic cell (DC)-based cancer therapy, provided that the vector can successfully be transfected into dendritic cells. We propose a simple and widely applicable method for providing the signal sequence.  相似文献   
26.
The purpose of this study was to determine if salivary chromogranin a secretion in dogs exhibits a circadian rhythm. Saliva sampling was performed during three different sessions occurring in three nonconsecutive 24-h periods. Sixteen healthy adult beagle dogs (8 males and 8 females) were moved to a sampling room and housed individually in cages. Saliva samples were obtained every 4 h from 12:00 p.m. to 12:00 p.m. the following day. In the interest of habituation, saliva was obtained hourly from each dog 3 h before the experiment was started. Salivary chromogranin A concentrations were measured using an enzyme-linked immunosorbent assay. No circadian rhythm was detected for salivary chromogranin A secretion, and no differences in salivary chromogranin A concentrations measured every 4 h were demonstrated during the 24-h cycle in dogs.  相似文献   
27.
28.
Diallel analysis has revealed that anther culturability in rice (Oryza sativa L.) is a quantitative trait controlled by the nuclear genome. Mapping of anther culturability is important to increase the efficiency for green plant regeneration from microspores. In the previous study, we detected distorted segregation of RFLP markers in rice populations derived from the anther culture of an F1 hybrid between a japonica cultivar ‘Nipponbare’ and an indica cultivar ‘Milyang 23’. To clarify the association between chromosomal regions showing distorted segregation and anther culturability, the anther culturability of doubled haploid lines derived from the same cross combination was examined, and the association between alleles of the RFLP markers, which exhibiting the most distorted segregation on chromosomes 1, 3, 7, 10 and 11, and the anther culturability was evaluated. One region on chromosome 1 was found to control callus formation from microspores, and one region on chromosome 10 appeared to control the ratio of green to albino regenerated plants. In both regions, the Nipponbare allele had positive effects. Three regions on chromosomes 3, 7 and 11, however, showed no significant effect on anther culturability. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
29.
Fisheries Science - Traditional Japanese koji-fermented tofu (tofuyo) processing was simulated to make fermented seafood. The koji fermentation process at room temperature was applied to steamed...  相似文献   
30.
We demonstrated that the inorganic phosphate (P(i)) requirement for growth of Japanese red pine (Pinus densiflora Sieb. & Zucc.) seedlings is increased by elevated CO(2) concentration ([CO(2)]) and that responses of the ectomycorrhizal fungus Pisolithus tinctorius (Pers.) Coker & Couch to P(i) supply are also altered. To investigate the growth response of non-mycorrhizal seedlings to P(i) supply in elevated [CO(2)], non-mycorrhizal seedlings were grown for 73 days in ambient or elevated [CO(2)] (350 or 700 micromol mol(-1)) with nutrient solutions containing one of seven phosphate concentrations (0, 0.02, 0.04, 0.06, 0.08, 0.10 and 0.20 mM). In ambient [CO(2)], the growth response to P(i) was saturated at about 0.1 mM P(i), whereas in elevated [CO(2)], the growth response to P(i) supply did not saturate, even at the highest P(i) supply (0.2 mM), indicating that the P(i) requirement is higher in elevated [CO(2)] than in ambient [CO(2)]. The increased requirement was due mainly to an altered shoot growth response to P(i) supply. The enhanced P(i) requirement in elevated [CO(2)] was not associated with a change in photosynthetic response to P(i) or a change in leaf phosphorus (P) status. We investigated the effect of P(i) supply (0.04, 0.08 and 0.20 mM) on the ectomycorrhizal fungus P. tinctorius in mycorrhizal seedlings grown in ambient or elevated [CO(2)]. Root ergosterol concentration (an indicator of fungal biomass) decreased with increasing P(i) supply in ambient [CO(2)], but the decrease was far less in elevated [CO(2)]. In ambient [CO(2)] the ratio of extramatrical mycelium to root biomass decreased with increasing P(i) supply but did not change in elevated [CO(2)]. We conclude that, because elevated [CO(2)] increased the P(i) requirement for shoot growth, the significance of the ectomycorrhizal association was also increased in elevated [CO(2)].  相似文献   
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