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51.
R. G. Erickson P. Thier 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1991,86(3):608-616
Summary Motion of background visual images across the retina during slow tracking eye movements is usually not consciously perceived so long as the retinal image motion results entirely from the voluntary slow eye movement (otherwise the surround would appear to move during pursuit eye movements). To address the question of where in the brain such filtering might occur, the responses of cells in 3 visuo-cortical areas of macaque monkeys were compared when retinal image motion of background images was caused by object motion as opposed to a pursuit eye movement. While almost all cells in areas V4 and MT responded indiscriminately to retinal image motion arising from any source, most of those recorded in the dorsal zone of area MST (MSTd), as well as a smaller proportion in lateral MST (MST1), responded preferentially to externally-induced motion and only weakly or not at all to self-induced visual motion. Such cells preserve visuo-spatial stability during low-velocity voluntary eye movements and could contribute to the process of providing consistent spatial orientation regardless of whether the eyes are moving or stationary. 相似文献
52.
Three measures of lower extremity function were compared in a homogenous population of ALS patients. Isokinetic dynamometry was shown to be a sensitive tool for change in strength over time. It demonstrated positive correlations with gait velocity as well as other behavioral measures. Manual muscle tests were relatively insensitive and no more reliable than isokinetics. Isokinetics are a useful adjunct in the assessment of ALS. 相似文献
53.
Madeline Rose Keleher Kathryn Erickson Harry A. Smith Katerina J. Kechris Ivana V. Yang Dana Dabelea Jacob E. Friedman Kristen E. Boyle Thomas Jansson 《Diabetes》2021,70(3):745
An adverse intrauterine environment is associated with the future risk of obesity and type 2 diabetes. Changes in placental function may underpin the intrauterine origins of adult disease, but longitudinal studies linking placental function with childhood outcomes are rare. Here, we determined the abundance and phosphorylation of protein intermediates involved in insulin signaling, inflammation, cortisol metabolism, protein glycosylation, and mitochondrial biogenesis in placental villus samples from healthy mothers from the Healthy Start cohort. Using MANOVA, we tested the association between placental proteins and offspring adiposity (fat mass percentage) at birth (n = 109) and infancy (4–6 months, n = 104), and adiposity, skinfold thickness, triglycerides, and insulin in children (4–6 years, n = 66). Placental IGF-1 receptor protein was positively associated with serum triglycerides in children. GSK3β phosphorylation at serine 9, a readout of insulin and growth factor signaling, and the ratio of phosphorylated to total JNK2 were both positively associated with midthigh skinfold thickness in children. Moreover, peroxisome proliferator–activated receptor γ coactivator (PGC)-1α abundance was positively associated with insulin in children. In conclusion, placental insulin/IGF-1 signaling, PGC-1α, and inflammation pathways were positively associated with metabolic outcomes in 4- to 6-year-old children, identifying a novel link between placental function and long-term metabolic outcomes. 相似文献
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Rosano A Smithells D Cacciani L Botting B Castilla E Cornel M Erickson D Goujard J Irgens L Merlob P Robert E Siffel C Stoll C Sumiyoshi Y 《Journal of epidemiology and community health》1999,53(10):630-635
OBJECTIVE: To examine time trends in neural tube defects (NTD) prevalence from 1987 to 1996 in relation to the primary prevention policies for folic acid supplementation strategies in different countries. DESIGN: Retrospective time trends analysis of NTD prevalence. SETTING: 11 birth defect registries of congenital malformations participating in the International Clearinghouse for Birth Defects Monitoring System, in the period from 1 July 1987 to 30 June 1996. SUBJECTS: 8207 live births, stillbirths and terminated pregnancies affected by anencephaly or spina bifida registered by the 11 participating centres 1987-1996. OUTCOME MEASURES: Prevalence rate ratios based on the annual rates, using the Poisson regression model. RESULTS: During the study period a significant fall in prevalence rates for all NTD is present in Atlanta (USA), England and Wales, Hungary and Japan, and a significant rise in Norway and South America. After adjusting for the secular trends observed in the earlier years of the study, no significant trend can be attributed to preventive strategies. Data on NTD prevalence are supplemented with information on folate awareness among some of the populations studied. CONCLUSION: There is no evidence that, up to the middle of 1996, any change in time trend was attributable to the introduction of national folate supplementation policies. The possible effectiveness of folate supplementation policies for the reduction of NTD clearly needs to be tried and studied for several more years. Considering that in the Western world about 50% of pregnancies are unplanned, a policy that rests on action taken before conception can only have limited success. Strategies based on food enrichment, such as was introduced in the USA from the beginning of 1998, may prove to be more successful. 相似文献
60.
Neural-tube defects 总被引:3,自引:0,他引:3