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Zoï Kapoula Maria Pia Bucci Frederic Jurion Julie Ayoun Farzaneh Afkhami Dominique Brémond-Gignac 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2006,245(7):931-936
Aim There is a controversy as to whether dyslexic children present visuo-motor disabilities such as vergence and accommodative
problems assessed with orthoptic tests. The purpose of this study is to re-examine this issue in a large population of children.
Methods Extensive orthoptic evaluation was made in 57 dyslexic and 46 non-dyslexic (“normal”) age-matched children. Convergence and
divergence capacities were evaluated at two distances (30 cm and 400 cm).
Results Binocular vision measured with stereo-acuity tests was normal in dyslexics. In contrast, the near point of convergence was
significantly more remote in dyslexics; most importantly, divergence at both far and near distance was significantly more
reduced in dyslexics (median value 4 pD and 10 pD, respectively, at far and near) than in “normals” (median value 6 pD and
12 pD, at far and near).
Conclusion The existence of the divergence deficit at far distance indicates the presence of deficit of divergence per se, independently
from convergence and accommodation relaxation. This result is novel and corroborated by physiological studies indicating distinct
control of convergence and divergence, both at the cortical and subcortical premotor level. We conclude that vergence deficits
are frequently present in dyslexics, and that dyslexics should be re-educated; training should address distinctively convergence
and divergence subsystems. 相似文献
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Maternal and fetal plasma vitamin E to total lipid ratio and fetal RBC antioxidant function during gestational development 总被引:1,自引:0,他引:1
S Abbasi A Ludomirski V K Bhutani S Weiner L Johnson 《Journal of the American College of Nutrition》1990,9(4):314-319
Placental transfer of vitamin E was investigated from 19 to 35 weeks of gestation by analysis of fetal and maternal blood samples for total tocopherol, total lipids, and fetal red blood cell antioxidant reserves. Fifty-two fetal blood samples were obtained under ultrasonographic guide by percutaneous umbilical blood sampling. Thirteen were from fetuses with gestational age less than or equal to 22 weeks (x serum vitamin E = 0.4 +/- 0.14 mg/dl), 12 were from fetuses at 23-27 weeks gestation (x serum vitamin E = 0.4 +/- 0.21 mg/dl), and 27 were from fetuses with gestational age 28-38 weeks (x serum level = 0.37 +/- 0.18). Total lipid levels ranged from 140 to 216 mg/dl. Maternal plasma vitamin E concentrations correlated significantly with concurrent values in the fetus. There were no significant differences in serum vitamin E levels or vitamin E to total lipid ratio in samples from early, mid, or late gestation in either the mother or fetus. Red blood cell antioxidant reserve on samples from 18 fetuses were grossly abnormal by three different functional assays. On the basis of these data, placental transfer of vitamin E appears to be relatively constant through advancing gestation. Red blood cell antioxidant reserve is uniformly low. 相似文献
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Hadis Sabour Arash Hossein-Nezhad Zhila Maghbooli Farzaneh Madani Elham Mir Bagher Larijani 《Gynecological endocrinology》2006,22(10):585-589
Poor maternal vitamin D status affects fetal and infant skeletal growth. The aim of the present study was to determine the association between newborn outcomes and maternal calcium and vitamin D intakes. Four hundred and forty-nine pregnant women, healthy at the point of delivery, and their newborns were enrolled in the study, which was performed in three university hospitals in Tehran in March 2004. Maternal anthropometric data and energy, protein, calcium and vitamin D intakes were collected, and newborn outcomes (weight, length, head circumference and 1-min Apgar score) were determined. Almost two-thirds of the mothers (64.3%) took no supplements during pregnancy. Only one-third of the mothers (33.8%) had adequate intakes of calcium and vitamin D (from supplements and foods) compared with the Recommended Dietary Allowances. Mean length at birth and 1-min Apgar score were higher in newborns whose mothers had adequate calcium and vitamin D intake than in newborns whose mothers had inadequate intake (p = 0.03 and p = 0.04, respectively). Significant correlations were found between adequate maternal calcium and vitamin D intake and both appropriate birth weight and 1-min Apgar score of newborns and weight gain of mothers during pregnancy. Informing mothers of the critical importance of consuming adequate amounts of calcium and vitamin D seems necessary. 相似文献
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Approximately 5% of Americans over age 65, or 1.5 million individuals, currently reside in the nations's 20,000 nursing homes. The authors present material that lead to three conclusions about this population. First, nutritional deficiencies are common underlying causes of adverse clinical outcomes. Second, nutritional deficiencies are frequently not recognized. Third, opportunities for preventing or correcting undernutrition exist, provided that the significant and reversible nature of the nutrient deficiencies are identified. 相似文献