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1.
Sau3AI-generated DNA fragments of the Shigella sonnei large plasmid encoding the form I antigen were cloned into Escherichia coli with cosmid vector pHSG262. One resulting plasmid, designated pJK1137, was studied further. Restriction endonuclease mapping and analysis of transposon Tn3 insertion mutants demonstrated that the form I antigen genes were located within a region of about 12.6 kb consisting of the two contiguous HindIII fragments of 1.26 kb and 12.4 kb. The results of complementation studies between Tn3 insertion mutants of pJK1137 and recombinant plasmids carrying different parts of the form I antigen genes indicated that the 12.6 kb DNA sequence contained at least four gene clusters, regions A, B, C and D. Analysis of radioactively labelled proteins in minicells demonstrated that the DNA sequence of about 12.6 kb coded for at least four specific proteins of 42, 23, 48 and 39 kDa. The former two were coded by region A, the latter two by region D.  相似文献   
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Regime shifts of climatic and environmental conditions potentially affect the productivity of fishery resources, posing challenges in stock management. The stocks of the Japanese flying squid (Todarodes pacificus) are suspected to suffer from regime shifts, but detecting the occurrence of regime shifts in this species is generally difficult and unreliable because the short-lived nature of this species inherently confounds the effect of regime shifts with observation and process errors. Here we developed a new state-space assessment model to evaluate the influence of regime shifts on the spawner-recruit relationship of the Japanese flying squid. The model simultaneously estimates the population dynamics of multiple stocks that could share some life history parameters, thereby stabilizing parameter inference. We demonstrate that two regime shifts in productivity around 1991 and 2015 caused two- to threefold changes of maximum sustainable yields. The model with regime shifts clarifies the relationship between fishing pressure and spawner abundance that is difficult to detect in a model with no regime shift. The state-space approach is a promising tool for accurately assessing stock status by separating the recruitment process from observation errors and is expected to contribute to the effective management of marine biological resources sensitive to regime shifts.  相似文献   
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Colchicine-binding protein (CBP) was purified from a cultured carrot cell extract by DEAE-Sephacel, phosphocellulose and Sephadex G200 column chromatographies. The purified CBP separated into three bands on SDS-polyacrylamide gel electrophoresis. One of them reacted with a monoclonal antibody against chick brain alpha-tubulin and the other two with that against beta-tubulin. Colchicine-binding activity of the purified protein was enhanced by tartrate and inhibited little by an excess of podophyllotoxin. It decayed following first order kinetics, but was more stable than the CBP in the crude extract. The binding constant of the purified CBP for colchicine was 0.57 microM-1 and the number of binding sites of colchicine per mg protein was about 2 nmol. This binding constant is about ten times lower than that of porcine brain tubulin under identical conditions.  相似文献   
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1. 1. The objective of this paper is to investigate the indoor environment from the viewpoint of interaction between physical environment and the human responses. The field survey has been conducted over 1 year.

2. 2. A continuous measurement has been carried out for 1 week and distribution of variables have been measured for 1 day.

3. 3. The attitude of workers was investigated by a questionnaire.

4. 4. As the result, average luminance represented more than 1000 lx in the new building, in contrast with less tha 300 lx in the existing building.

5. 5. There was a significant difference of the occupants' response to the light environment between the two buildings.

6. 6. Measured thermal conditions are on the edge of the ASHRAE comfort envelope in summer, and in the neighborhood of the lower dry limit of the envelope in spring.

7. 7. The occupants' evaluations were remarkably changed before and after the moving. The office environment is better than that of the factory.

Author Keywords: Office; post occupancy evaluation; physical environmental condition; occupants' evaluation  相似文献   

6.
Two proteins (Mr 46,000, pI 6.4 and 7.0), the phosphorylation of which was increased by any of the membrane-perturbing agents in parallel with activation of NADPH oxidase in intact guinea-pig polymorphonuclear leukocytes in our previous study (Okamura, N., Ohashi, S., Nagahisa, N. and Ishibashi, S. (1984) Arch. Biochem. Biophys. 228, 270-277), were also phosphorylated in a cell-free system prepared from the leukocytes. The in vitro phosphorylation of these two proteins was stimulated by the addition of phosphatidylserine in the presence of higher concentrations of Ca2+ (300-500 microM). The phosphorylation was further increased when protein kinase C partially purified from guinea-pig brain was added to the system. At a low concentration of Ca2+ (about 10 microM), stimulation of the phosphorylation was not attained by phosphatidylserine alone but required the addition of diacylglycerol or phorbol myristate acetate. On the other hand, the increase in the phosphorylation was inhibited by H-7, an inhibitor for protein kinase C. These results indicate that protein kinase C is involved in the phosphorylation of the two proteins, which may be related to the superoxide anion production stimulated by various membrane-perturbing agents.  相似文献   
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Major depressive disorder (MDD) is a common psychiatric disorder that involves marked disabilities in global functioning, anorexia, and severe medical comorbidities. MDD is associated with not only psychological and sociocultural problems, but also pervasive physical dysfunctions such as metabolic, neurobiological and immunological abnormalities. Nevertheless, the mechanisms underlying the interactions between these factors have yet to be determined in detail. The aim of the present study was to identify the molecular mechanisms responsible for the interactions between MDD and dysregulation of physiological homeostasis, including immunological function as well as lipid metabolism, coagulation, and hormonal activity in the brain. We generated depression-like behavior in mice using chronic mild stress (CMS) as a model of depression. We compared the gene expression profiles in the prefrontal cortex (PFC) of CMS and control mice using microarrays. We subsequently categorized genes using two web-based bioinformatics applications: Ingenuity Pathway Analysis and The Database for Annotation, Visualization, and Integrated Discovery. We then confirmed significant group-differences by analyzing mRNA and protein expression levels not only in the PFC, but also in the thalamus and hippocampus. These web tools revealed that hepatocyte nuclear factor 4 alpha (Hnf4a) may exert direct effects on various genes specifically associated with amine synthesis, such as genes involved in serotonin metabolism and related immunological functions. Moreover, these genes may influence lipid metabolism, coagulation, and hormonal activity. We also confirmed the significant effects of Hnf4a on both mRNA and protein expression levels in the brain. These results suggest that Hnf4a may have a critical influence on physiological homeostasis under depressive states, and may be associated with the mechanisms responsible for the interactions between MDD and the dysregulation of physiological homeostasis in humans.  相似文献   
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