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1.
Bacteriocin sensitivity typing according to the method of Traub (Appl. Microbiol. 1971. 21: 837-840) was carried out on 226 clinical isolates of Serratia marcescens obtained from inpatients at Nagasaki University Hospital during the period from January 1976 to December 1978. The isolates were divided into 16 different bacteriocin types, mainly 26, 4, and 9. The distribution of the types suggests that Serratia marcescens infections may be caused by cross infection. Reproducibility of bacteriocin typing and the relationship between serotypes (O-antigen) and bacteriocin types are discussed in regard to the application of this method to the study of nosocomial infections.  相似文献   
2.
The flowering of Lemna paucicostata 6746 grown on 14-h photoperiodwas enhanced by the addition of high concentrations of ironto the medium, which also increased the endogenous iron concentration.The addition of asparagine, aspartate, glutamate, -alanine,glycine or serine to the medium also increased the endogenousiron level, resulting in the promotion of flowering. In contrast,the addition of cysteine, cystine, glutamine, arginine, threonineor phenylalanine lowered the endogenous iron level, resultingin the inhibition of flowering. Glycine and asparagine added to the medium during an inductive96-h dark period did not promote iron uptake and had no effecton flowering, but when added during the subsequent 120-h lightperiod, they promoted both iron uptake and flowering response.The increase in the endogenous iron level seems to favor floraldevelopment rather than induction of photoperiodic floweringof Lemna paucicostata 6746. (Received September 8, 1986; Accepted March 31, 1987)  相似文献   
3.
Bacteriological examinations were performed on the first case of infant botulism in Japan (an infant boy aged 79 days at onset of illness). Clostridium botulinum type A toxin and organisms were detected continually in the stools of the infant for at least 31 days and 39 days, respectively. The highest levels of the toxin and of the population of the organisms, 7.8 X 10(4) LD50/g and 1.3 X 10(6) colony forming units (cfu)/g, were detected in the stool specimen taken on the 20th day of illness. Type A organisms were detected also in the honey fed to the infant before onset of illness, teats of his feeding bottle, soil specimens taken at the house entry and the vacuum-cleaner dust. Fecal excretion of the toxin and organisms was no longer detected from the 68th day of illness and he recovered.  相似文献   
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The effect of copper on flowering and growth of Lemna paucicostata6746 and Lemna gibba G3 in a copper-containing medium is nullifiedby the addition of EDTA, ammonium ions or salicylic acid tothe medium or a decrease in its nitrate concentration. Thesefactors were examined for their effects on the absorption ofcopper by the plants. The addition of EDTA to the medium completelyinhibited the absorption of copper in both species, thus eliminatingthe copper effect. Ammonium ions also inhibited copper absorption,their effectiveness rising with their concentration. Loweringthe nitrate concentration in the medium nullified the coppereffect on flowering in L. paucicostata 6746, and the additionof salicylic acid to the medium also nullified the copper effectin L. gibba G3, both without affecting the absorption of copper. (Received June 7, 1982; Accepted August 27, 1982)  相似文献   
6.
Annual net production was estimated in the secondary coppice forest near Tokyo, which was dominated by a deciduous oak,Quercus serrata Thunb. Lateral growth of stems and old branches was directly estimated by examining the annual rings for 35 shoots in a clear-cut quadrat of 10m×10m. Phytomasses of current organs were also weighed in the quadrat. Preharvest losses of current organs were determined by twelve 0.5 m2 litter traps for fine litter and twelve 6 m2 quadrats for woody litter. Branch production was also assessed indirectly by use of the stem-branch allometry and death of branches. The results of the indirect method were in sufficient agreement with the result of the direct one. Grazing loss of leaves from the canopy was estimated directly from the loss in leaf area and indirectly from the animal faeces caught by the litter traps. Net production of the canopy trees was 149 kg a−1 year−1, in which leaf production was 36.9 kg. Animals grazed about 14% of the leaf area by the end of the growing season. True consumption of leaves by animals was 7.6% of leaf production or 10% of leaf mass. Production of undergrowth, mainly a dwarf bamboo,Pleioblastus chino Makino, was 28 kg a−1 year−1, being 15% of the total stand production. Productivity of this forest was significantly higher than that of cool-temperate deciduous broadleaf forests.  相似文献   
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Fresh loquat leaves have been used as folk health herb in Asian countries for long time, although the evidence supporting their functions is still minimal. This study aimed to clarify the chemopreventive effect of loquat tea extract (LTE) by investigating the inhibition on proliferation, and underlying mechanisms in human promyelocytic leukemia cells (HL-60). LTE inhibited proliferation of HL-60 in a dose-dependent manner. Molecular data showed that the isolated fraction of LTE induced apoptosis of HL-60 as characterized by DNA fragmentation; activation of caspase-3, -8, and -9; and inactivation of poly(ADP)ribose polymerase. Moreover, LTE fraction increased the ratio of pro-apoptotic Bcl-2-associated X protein (Bax)/anti-apoptotic myeloid cell leukemia 1 (Mcl-1) that caused mitochondrial membrane potential loss and cytochrome c released to cytosol. Thus, our data indicate that LTE might induce apoptosis in HL-60 cells through a mitochondrial dysfunction pathway. These findings enhance our understanding for chemopreventive function of loquat tea.  相似文献   
9.
Separation of the diastereomers of glycosyl sulfoxides differing in the sulfur chirality has been difficult. This article presents a fast and scalable method for their diastereoseparation using a chiral stationary phase. The usefulness of this method was demonstrated in a 500‐mg scale separation within 20 min, and in the separation of trisaccharyl sulfoxide diastereomers. Chirality 28:534–539, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
10.
Expression of nephrin, a crucial component of the glomerular slit diaphragm, is downregulated in patients with proteinuric glomerular diseases. Using conditionally immortalized reporter podocytes, we found that bystander macrophages as well as macrophage-derived cytokines IL-1beta and TNF-alpha markedly suppressed activity of the nephrin gene promoter in podocytes. The cytokine-initiated repression was reversible, observed on both basal and inducible expression, independent of Wilms' tumor suppressor WT1, and caused in part via activation of the phosphatidylinositol-3-kinase/Akt pathway. These results indicated a novel mechanism by which activated macrophages participate in the induction of proteinuria in glomerular diseases.  相似文献   
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