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61.
Rahman S Khalid N Zaidi JH Ahmad S Iqbal MZ 《Journal of Zhejiang University. Science. B》2006,7(9):732-737
INTRODUCTION Blood-Pb levels are taken as representative of dose/exposure, as all clinical symptoms resulting from the toxic effects of Pb are manifested mainly in blood. Lead exposure of children correlates with de- creased IQ, symptoms of hyper kinesis or minima brain dysfunction, poor learning, or defects in specific neuromotor tasks (Landgrin et al., 1980). Large number of observations over the years has associated lead exposure with human diseases (McMichael and Johnson, 1982). Ca… 相似文献
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INTRODUCTION Elaeagnus angustifolia Linn. is an Eurasian tree that has become naturalized and has invaded zones along watercourses in many arid and semiarid regions of the world. These habitats are characterized by ver-tical environmental gradients, and hence trees have developed much plasticity to adapt to the wide range of site conditions (Klich, 2000). E. angustifolia plays a very important role in maintaining ecosystem func-tion in the hyper arid areas of Xinjiang, China, be-cause o… 相似文献
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The aim of this study was to examine the variability of the oxygen uptake (VO2) kinetic response during moderate- and high-intensity treadmill exercise within the same day (at 06:00, 12:00 and 18:00 h) and across days (on five occasions). Nine participants (age 25 +/- 8 years, mass 70.2 +/- 4.7 kg, VO2max 4137 +/- 697 ml x min(-1); mean +/- s) took part in the study. Six of the participants performed replicate 'square-wave' rest-to-exercise transitions of 6 min duration at running speeds calculated to require 80% VO2 at the ventilatory threshold (moderate-intensity exercise) and 50% of the difference between VO2 at the ventilatory threshold and VO2max (50% delta; high-intensity exercise) on 5 different days. Although the amplitudes of the VO2 response were relatively constant (coefficient of variation approximately 6%) from day to day, the time-based parameters were more variable (coefficient of variation approximately 15 to 30%). All nine participants performed replicate square-waves for each time of day. There was no diurnal effect on the time-based parameters of VO2 kinetics during either moderate- or high-intensity exercise. However, for high-intensity exercise, the amplitude of the primary component was significantly lower during the 12:00 h trial (2859 +/- 142 ml x min(-1) vs 2955 +/- 135 ml x min(-1) at 06:00 h and 2937 +/- 137 ml x min(-1) at 18:00 h; P < 0.05), but this effect was eliminated when expressed relative to body mass. The results of this study indicate that the amplitudes of the VO2 kinetic responses to moderate- and high-intensity treadmill exercise are similar within and across test days. The time-based parameters, however, are more variable from day to day and multiple transitions are, therefore, recommended to increase confidence in the data. 相似文献
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This article describes the development and validation of the Learning Difficulties Assessment (LDA), a normed and web-based survey that assesses perceived difficulties with reading, writing, spelling, mathematics, listening, concentration, memory, organizational skills, sense of control, and anxiety in college students. The LDA is designed to (a) map individual learning strengths and weaknesses, (b) provide users with a comparative sense of their academic skills, (c) integrate research in user-interface design to assist those with reading and learning challenges, and (d) identify individuals who may be at risk for learning disabilities and attention-deficit/hyperactivity disorder (ADHD) and who should thus be further assessed. Data from a large-scale 5-year study describing the instrument's validity as a screening tool for learning disabilities and ADHD are presented. This article also describes unique characteristics of the LDA including its user-interface design, normative characteristics, and use as a no-cost screening tool for identifying college students at risk for learning disorders and ADHD. 相似文献
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Moor JH 《Ethics and Information Technology》1999,1(4):257-263
Computing plays an important role in genetics (and vice versa).Theoretically, computing provides a conceptual model for thefunction and malfunction of our genetic machinery. Practically,contemporary computers and robots equipped with advancedalgorithms make the revelation of the complete human genomeimminent – computers are about to reveal our genetic soulsfor the first time. Ethically, computers help protect privacyby restricting access in sophisticated ways to genetic information.But the inexorable fact that computers will increasingly collect,analyze, and disseminate abundant amounts of genetic informationmade available through the genetic revolution, not to mentionthat inexpensive computing devices will make genetic informationgathering easier, underscores the need for strong and immediateprivacy legislation. 相似文献
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Evaluation of the hepatoprotective and antioxidant activities of Rubus parvifolius L 总被引:1,自引:0,他引:1
Gao J Sun CR Yang JH Shi JM Du YG Zhang YY Li JH Wan HT 《Journal of Zhejiang University. Science. B》2011,12(2):135-142
The hepatoprotective and antioxidant activities of the n-butanol extract of Rubus parvifolius L. (RPL), a widely used medicinal plant, were evaluated. Results demonstrated that RPL extract possessed pronounced hepatoprotective
effects against carbon tetrachloride (CCl4)-induced hepatic injury in mice, which was at least partially attributed to its strong antioxidant capacity. Treatment with
RPL extract markedly attenuated the increases in serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST)
levels caused by CCl4 intoxication. It also significantly prevented the decrease in superoxide dismutase (SOD) activity and the increase in malondialdehyde
(MDA) content of liver tissue. Meanwhile, histopathological changes of hepatic damage were also remarkably ameliorated. Phytochemical
analysis based on high-performance liquid chromatography/tandem mass spectrometry (HPLC-MS/MS) revealed the presence of various
phenolic compounds, including caffeic acid conjugates, ellagic acid glycosides, and flavonol glycosides, which might be responsible
for the hepatoprotective and antioxidant activities of RPL. 相似文献