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41.
Liana Palermo Raffaella Nori Laura Piccardi Fabrizio Zeri Antonio Babino Fiorella Giusberti Cecilia Guariglia 《PloS one》2013,8(6)
The hypothesis that visual perception and mental imagery are equivalent has never been explored in individuals with vision defects not preventing the visual perception of the world, such as refractive errors. Refractive error (i.e., myopia, hyperopia or astigmatism) is a condition where the refracting system of the eye fails to focus objects sharply on the retina. As a consequence refractive errors cause blurred vision.We subdivided 84 individuals according to their spherical equivalent refraction into Emmetropes (control individuals without refractive errors) and Ametropes (individuals with refractive errors). Participants performed a vividness task and completed a questionnaire that explored their cognitive style of thinking before their vision was checked by an ophthalmologist. Although results showed that Ametropes had less vivid mental images than Emmetropes this did not affect the development of their cognitive style of thinking; in fact, Ametropes were able to use both verbal and visual strategies to acquire and retrieve information. Present data are consistent with the hypothesis of equivalence between imagery and perception. 相似文献
42.
Carly Rich Marco Geraci Lucy Griffiths Francesco Sera Carol Dezateux Mario Cortina-Borja 《PloS one》2013,8(6)
Background
When using accelerometers to measure physical activity, researchers need to determine whether subjects have worn their device for a sufficient period to be included in analyses. We propose a minimum wear criterion using population-based accelerometer data, and explore the influence of gender and the purposeful inclusion of children with weekend data on reliability.Methods
Accelerometer data obtained during the age seven sweep of the UK Millennium Cohort Study were analysed. Children were asked to wear an ActiGraph GT1M accelerometer for seven days. Reliability coefficients(r) of mean daily counts/minute were calculated using the Spearman-Brown formula based on the intraclass correlation coefficient. An r of 1.0 indicates that all the variation is between- rather than within-children and that measurement is 100% reliable. An r of 0.8 is often regarded as acceptable reliability. Analyses were repeated on data from children who met different minimum daily wear times (one to 10 hours) and wear days (one to seven days). Analyses were conducted for all children, separately for boys and girls, and separately for children with and without weekend data.Results
At least one hour of wear time data was obtained from 7,704 singletons. Reliability increased as the minimum number of days and the daily wear time increased. A high reliability (r = 0.86) and sample size (n = 6,528) was achieved when children with ≥ two days lasting ≥10 hours/day were included in analyses. Reliability coefficients were similar for both genders. Purposeful sampling of children with weekend data resulted in comparable reliabilities to those calculated independent of weekend wear.Conclusion
Quality control procedures should be undertaken before analysing accelerometer data in large-scale studies. Using data from children with ≥ two days lasting ≥10 hours/day should provide reliable estimates of physical activity. It’s unnecessary to include only children with accelerometer data collected during weekends in analyses. 相似文献43.
Courtney L. Olson Luz P. Acosta Natasha S. Hochberg Remigio M. Olveda Mario Jiz Stephen T. McGarvey Jonathan D. Kurtis David C. Bellinger Jennifer F. Friedman 《PLoS neglected tropical diseases》2009,3(10)
Background
Many studies have addressed the relationship between iron deficiency anemia (IDA) and cognitive impairment, but none have evaluated the role of non-iron deficiency anemia (NIDA). One of the main causes of NIDA in developing countries is AI, largely due to infectious diseases, whereby iron is shunted away from bio-available forms to storage forms, making it less accessible for use by host tissues. The objective of this study was to determine the effect of NIDA, due largely to AI in this context, on cognitive function after adjustment for potential confounders.Methodology
This cross-sectional study was conducted in Leyte, The Philippines among 322 children ages 7–18 years. Blood samples were collected and analyzed at the time of cognition testing. Three stool samples were collected and evaluated by the Kato Katz method for quantitative assessment for Schistosoma japonicum and geo-helminth infection. Socio-economic status (SES) was evaluated by survey. Linear regression models were used to quantify the adjusted relationship between performance in different cognitive domains and both IDA and NIDA.Principal Findings
After adjusting for age, sex, SES and nutritional status, children in the NIDA had lower scores on the PNIT (P = <0.05) and the WRAML memory domain (P<0.05) compared to children in the non-anemic group. Children in the IDA had lower performance on the PNIT compared to the non-anemic group after controlling for potential confounders (P<0.05).Conclusions
NIDA, predominantly due to AI in this context, was related to lower performance on two tests of cognitive function. This is likely due to decreased delivery of iron to host tissues in this context, including the CNS. 相似文献44.
45.
Brian A Stacy Mario Santoro Juan Alberto Morales Louis M Huzella Victor F Kalasinsky Allen Foley Nancy Mettee Elliott R Jacobson 《Diseases of aquatic organisms》2008,80(1):45-49
Eighteen green turtles Chelonia mydas recovered from the Atlantic and Gulf coasts of Florida and Tortuguero National Park, Costa Rica, were diagnosed with renal oxalosis by histopathological examination. Affected sea turtles included 14 adults and 4 immature animals, which comprised 26% (18/69) of green turtle necropsy cases available for review. Calcium oxalate deposition ranged from small to moderate amounts and was associated with granuloma formation and destruction of renal tubules. All affected turtles died from traumatic events or health problems unrelated to renal oxalosis; however, 1 immature turtle had notable associated renal injury. Crystal composition was confirmed by infrared and scanning electron microscopy and energy dispersive X-ray analysis. The source of calcium oxalate is unknown and is presumed to be of dietary origin. 相似文献
46.
Rajchenberg M 《Mycologia》2011,103(4):677-702
This is a review of the available knowledge on nuclear behavior of the mycelium within polypore genera (Agaricomycetes, Basidiomycota). Information on 68 genera showed that nuclear behavior is a distinct and consistent feature at genus level and can be coupled with phylogenetic differentiation. The sole exception was found in Polyporus, where different species with normal, heterocytic and astatocoenocytic nuclear behaviors were found. Of the 68 genera treated 41 (60.3%) displayed a normal nuclear behavior, nine (13.2%) were heterocytic, nine (13.2%) were astatocoenocytic and another eight (11.8%) were holocoenocytic. In 95% of the genera a unique compatibility system was found, with the exceptions of Antrodia, which includes both homothallic and bipolar species all associated with a normal nuclear behavior, and Spongipellis, in which bipolar and tetrapolar species are found, all displaying an astatocoenocytic nuclear behavior. Normal and heterocytic nuclear behaviors were associated mostly with tetrapolarity, astatocoenocity was associated mostly with bipolarity, and holocoenocity was associated with either bipolarity or purported homothallism. The combination of nuclear behavior with mating system and brown or white rot capability appeared as a strong feature characterizing and distinguishing the genera of polypores, each combination being valuable to differentiate between apparently related genera, as is supported by phylogenetic studies. Several examples are presented to support this idea, as well as the cases of species that are problematic to this concept. Poroid genera of Hymenochaetaceae were treated apart because of the lack of knowledge regarding their nuclear behavior. In addition new information on the sexuality and/or nuclear behavior of 15 polyporoid taxa is given. 相似文献
47.
48.
TLR9 expression and function is abolished by the cervical cancer-associated human papillomavirus type 16 总被引:4,自引:0,他引:4
49.
50.
Airoldi C Zona C Sironi E Colombo L Messa M Aurilia D Gregori M Masserini M Salmona M Nicotra F La Ferla B 《Journal of biotechnology》2010,156(4):317-324
Curcumin derivatives with high chemical stability, improved solubility and carrying a functionalized appendage for the linkage to other entities, have been synthesized in a straightforward manner. All compounds retained Curcumin ability to bind Aβ peptide oligomers without inducing their aggregation. Moreover all Curcumin derivatives were able to stain very efficiently Aβ deposits. 相似文献