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Perceptions of personal and group discrimination in 5 domains (jobs, pay, loans, promotions, and clubs) were investigated via telephone interviews with 902 respondents from different ethnic groups in Toronto. The reported analyses concern 6 ethnic groups, representing "visible," racial minorities (Blacks, Chinese, and South Asians) as well as White minorities (Italians, Jews, and Portuguese). The personal/group discrimination discrepancy (i.e., perceiving greater discrimination toward one's group than oneself personally) was observed to varying extent across all domains and ethnic groups, though with some exceptions. Visible minorities perceived greater discrimination toward their group than did White minorities, especially in the economic domains of jobs, pay, and promotions. Among visible minorities, Black respondents perceived higher levels of group and personal discrimination than most other ethnic groups across domains, followed in turn by Chinese and South Asian respondents. By contrast, White minority group members perceived considerably less group or personal discrimination than members of visible minorities, except for Jewish respondents who reported greater group discrimination in joining clubs than any other ethnic group. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Si–C films with the Si compositions ranging from 40 to 70% have been grown by Cat-CVD using dimethylsilane [DMSi, Si(CH3)2H2] compounds. Tetraethoxysilane [TEOS, Si(OC2H5)4] and dimethyldimethoxysilane [DMDMOS, Si(CH3)2(OCH3)2] gas source gave us Si–C–O (C-doped SiOx) films with wide ternary alloy compositions. The dielectric constant of a Si–C film has been evaluated by CV measurements (at 1 MHz) using Al/Si–C/n-Si(001)/Cu MIS structure. The relative dielectric constant value of a Si–C film was estimated to be 3.0. The resistivity of the Si–C layer with 1 mm diameter and 0.24 μm thickness was estimated to be more than 24.5 Gohm·cm. These results gave us promising characteristics of Si–C and Si–C–O films grown by alkylsilane- and alcoxysilane-based Cat-CVD.  相似文献   
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Electrical cables in nuclear power generating stations must be highly reliable. For further improvement of reliability, the development of nondestructive diagnoses seems desirable for cable maintenance. The authors have been studying residual voltage for developing a diagnosis of electrical cables. The purpose of this paper is to give a foundation for development of diagnostic technology for detecting the irradiated degradation; the relations between γ-irradiation dose and the leakage current, the discharge current, and the residual voltage were studied and attempts made to calculate the amount of polarized charge and characteristic dielectric relaxation times by using data on the residual voltage. The calculated results agreed with the results obtained from the leakage current and the discharge current. These results suggest that the residual voltage in diagnostic technology for detecting the irradiated degradation can be employed.  相似文献   
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We examined the changes of the number of FdU MP binding sites of thymidylate thynthase (TS-BS) in Yoshida sarcoma after administration of 5-FU to the tumor bearing rats. We also investigated the optimal dose of CDDP for the increase of intracellular folate level. In the group received consecutive 7-days administration of UFT (U-7 group), total TS-BS was significantly increased compared with non-treatment group and the group received only UFT (U-1 group). For free TS-BS, however, there was no difference despite of UFT administration. Thymidylate synthase inhibition rate (TSIR) was, therefore, significantly high in U-7 group compared with U-1 group. It seemed necessary to take some counter measure for the induction of TS in the tumor tissue when 5-FU chemotherapy was performed. The optimal dose of CDDP as a modulator of 5-FU was 1 mg/kg in rat when it was estimated from the changes of intracellular folate levels after administration, which was less than the dose to reveal its own anticancer effect.  相似文献   
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BACKGROUND: It is commonly assumed that some immunological disorder may play a part in the pathogenesis of sarcoidosis. Previous studies by several groups have shown a significant association with HLA-DR antigens in patients with sarcoidosis. In this study, restriction fragment length polymorphism (RFLP) analysis of the HLA-DR gene was designed to confirm the association at the gene level and to look for a gene rearrangement which may influence susceptibility to sarcoidosis. METHODS: Thirty two unrelated Japanese patients with sarcoidosis were tested for HLA antigens and subjected to RFLP analysis after digestion with Eco RI, Pst I, Bam HI, Pvu II, and Hind III by using an HLA-DR beta cDNA probe. A group of 47 unrelated healthy Japanese subjects served as controls. Frequencies of each restriction fragment were compared between the patients and the control subjects. Correlation between fragment frequencies and clinical features were also analysed. RESULTS: No restriction fragments of HLA-DR beta gene were found specific to the patients with sarcoidosis. The RFLP analysis could detect polymorphism of HLA-DR beta genes that was not distinguishable by conventional serological methods. Several restriction fragments of the DR beta gene were seen only in DRw52 positive individuals, and showed higher frequencies in the patients than in control subjects. The patients with these DNA fragments were likely to have limited stage disease with no ophthalmic involvement. CONCLUSIONS: An association between HLA and sarcoidosis was noted at the DNA level, although no restriction fragments were specific for this disease. RFLP analysis of the HLA gene is a more useful method than the usual HLA typing, and should be the first step in identifying the gene sequence which is connected with susceptibility to sarcoidosis.  相似文献   
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Appropriately substituted 2,3-dihydro-7H-thiazolo[3,2-a]pyrimidin-7-ones 9-12 and 18 were considered as annulated analogues of HEPT (1-[(2-hydroxyethoxy)methyl]-6-(phenylthio)-thymine), and some of these compounds were also found active against HIV-1, the most active one being 2,3-dihydro-5-[(3,5-dimethylphenyl)methyl]-3-ethoxy-6-ethyl-7H- thiazolo[3,2-a]pyrimidin-7-one (10b). S-Alkylation of 5-alkyl-6-(arylmethyl)-2-thiouracils 1-4 was performed with 2-bromoacetaldehyde acetals to furnish the S-[bis(alkoxy)ethyl] derivatives 5-8 and with allyl bromide to furnish S-allyl derivatives 17. The target compounds 9-12 were obtained by an N1 regioselective intramolecular cyclization reaction of silylated 5-8 using trimethylsilyl trifluoromethanesulfonate (TMS triflate) as the catalyst. Treatment of the S-allyl derivatives 17 with bromine in dry methylene chloride afforded the 3-(bromomethyl) derivatives 18.  相似文献   
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