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Intracerebral infection of mice aged 2-3 days with hepatitis C virus (HCV) from chronically infected suckling mouse brain cultures and porcine embryo cells resulted in the death of animals after 12-14 days. Repeated passages of HCV in animals decreased the incubation period to just 3-4 days. Blood serum of surviving mice collected during the 4th week postinfection contained antiHCV antibodies detected by enzyme immunoassay and hemagglutination inhibition test. The results are proof of creation of a new in vivo model of experimental HCV infection.  相似文献   
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Corrosion of aluminium in mixtures of salts and effect of copper ions Corrosion of aluminium has been studied in stagnant condition, in mixtures of salts, NaCl + NaHCO3, Na2CO3 + NaHCO3 and NaCl + Na2CO3; effect of addition of copper ions has also been studied. It has been found that (shallow) pits are formed only when both chloride and bicarbonate are present. Addition of copper ions occasionally increases the numbers of pits but may some times decrease corrosion.  相似文献   
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IQs of rapists were compared to IQs of nonrapist prisoners convicted of violent crimes and nonrapist prisoners convicted of nonviolent crimes. Subjects were 136 male convicted felons in the Kentucky State Penitentiary. Determination of violent vs. nonviolent crimes other than rape was made upon consultation with a Kentucky Commonwealth Attorney. The results revealed significantly lower IQs for rapists compared to nonrapists convicted of violent crimes and compared to heterogeneous nonrapist convicts. The present research supports the findings of Karacan and co-workers, indicating a general tendency for rapists to have lower IQs than other convicted prisoners.  相似文献   
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Three experiments examined the influence of videotaped classroom events on the academic performance and study behavior of reading-disabled and normally reading children in grades 1 through 6. In experiments 1 and 2a an experimenter-controlled presentation of these distractors resulted in performance decrements, the magnitude of which was greater for higher difficulty tasks. The distractor effects were similar for the two groups in this condition. However, when the children themselves were allowed to control their degree of exposure to the same distractors in experiment 2b, the reading-disabled children were less likely to act to escape the distraction. Results are discussed in terms of children's metacognitive awareness of distraction, and implications for the classroom are considered.  相似文献   
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The results of PUVA treatment for severe alopecia areata (AA) were reviewed in 102 patients. Fifty-three per cent had greater than 90% regrowth of hair. Although these results appear to be encouraging, they differ little from what would be expected with no treatment. We consider that PUVA is not an effective treatment for AA.  相似文献   
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