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Summary Peripheral blood lymphocytes were cultured for 5 days with allogeneic tumor cells (allogeneic mixed lymphocyte/tumor cell culture), and subsequently cultured with recombinant interleukin-2 for 12 days. These cultured cells were found to be cytotoxic to autologous tumor cells. Results of two-color analysis using monoclonal antibodies to cell markers showed that more than 80% of their cultured cells were CD3+ cells, and CD4+ cells showed a higher distribution than CD8+ cells. However, CD8+ cells had a much higher killing activity with autologous tumor than did CD4+ cells, when estimated by an elimination study using monoclonal antibodies to T cell phenotypes and complement. The cold-target inhibition test showed that the cytotoxicity of these cells for autologous tumor cells was inhibited by unlabeled autologous tumor cells but not by unlabeled stimulator cells. Furthermore, about 40% of the cytotoxicity was suppressed by blocking of HLA class I antigen with a monoclonal antibody on autologous tumor cells. Thus, cytotoxic activity of lymphocytes to autologous tumor restricted by target cell HLA class I antigen is possibly induced by allogeneic tumor-stimulation.  相似文献   
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To identify the type of Verotoxins (VT) produced by Verocytotoxin-producing Escherichia coli (VTEC), a sensitive bead-enzyme-linked immunosorbent assay and polymerase chain reaction with common and specific primers to various VTs (VT1, VT2, VT2vha, VT2vhb, and VT2vp1) were developed. Together with colony hybridization tests with oligo- and polynucleotide probes, these methods were applied to VTEC isolates to type the VT produced. The toxin types of 26 of 37 strains were identified, but the reaction profiles in assays of the remaining 11 strains suggested the existence of new VT2 variants. The application of these identification procedures may be useful as a tool for clinical and epidemiological studies of VTEC infection.  相似文献   
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We cloned and sequenced two new Verotoxin 2 (VT2) variant genes: one from an Escherichia coli strain from a case of bovine diarrhea and the other from an E. coli strain from a patient with diarrhea. The nucleotide and amino acid sequences of these two genes were highly homologous with, but distinct from those of the VT2, VT2vha, VT2vhb, SLT-IIv (VT2vp1) and SLT-IIva (VT2vp2) genes. Their nucleotide sequences were much more closely homologous to that of VT2vh than to that of VT2vp. Search for these two new genes in other Verocytotoxin-producing E. coli strains resulted in the isolation of 2 strains carrying one of the new VT2 variant genes, one strain from Tokyo and the other from Canada.  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.
In order to establish industrial production of 5′-inosinic acid (5′-IMP), a permeability mutant, KY13171, of Brevibacterium ammoniagenes, which accumulated 7 to 8 grams of 5′-IMP per liter and 4 to 6 grams of hypoxanthine (Hx) per liter (calculated as 5′-IMP), was improved by a genetical procedure. Further improved mutants were selected stepwise through repeating mutational work. The finally selected mutant. KY13369, accumulated 20 to 27 grams of 5′-IMP per liter, but not Hx.

Increased productivity of 5′-IMP and decreased productivity of Hx were not caused by the changes in 5′-IMP degrading activity, because these activities were not significantly different among the mutants. These results appear to indicate that the increased accumulation of 5′-IMP may be caused by the improvement in membrane permeability for 5′-IMP. However, the changes in phospholipid and fatty acid compositions were not enough to explain the increased permeability.  相似文献   
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