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The preservation of the effect of dynamic scanning of a part of the orientation diapason during development of neuron responses in the primary visual cortex of cat was examined after equalization of their latencies and after estimation of only highly significant fragments of their reactions. It was found that this effect was preserved in 13 neurons out of 17 examined ones: it remained invariable in 7 units of this group and was modified due to a shift of the scanning beginning along the diapason of orientations, to an increase of scanning diapason or to a change of scanning direction. The stabilization of the orientational tuning occurred only in 4 cells after equalization of latencies. The obtained results confirm that the dynamic changes of orientation tuning in the majority of visual cortex neurons are connected with reorganization of the time pattern of the reaction, as suggested by the hypothesis of the spatial-temporal orientation coding in the visual system.  相似文献   
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A study of the effect of the main risk factors of atherosclerosis in coronary patients on the prevalence of lipoidosis and prelipid changes in the aortal intima showed a week interrelationship between the studied risk factors and prevalence of lipoidosis. A noticeable significant interrelationship of the prevalence of prelipid changes in the aortal intima, patient's age, the IRI level and alpha-XC concentration in the blood plasma was established. An equation was described. A nomogram was presented permitting determination of the prevalence of prelipid changes in the aortal intima and, consequently, the phase of a course of atherosclerosis during the patient's lifetime on the basis of the above risk factors.  相似文献   
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Changes in the duration of the Achilles reflex were studied in subclinical disturbances of thyroid function. For this purpose the duration of the Achilles reflex, the levels of T4, T3, iodine protein bound TSH and cholesterol were investigated in children admitted to hospital with the general diagnosis of the "euthyroid goiter". Clinical and laboratory findings revealed subclinical types of the diffuse toxic goiter, hypothyrosis, chronic thyroiditis, endemic goiter, nodular goiter, pubertal struma and sporadic euthyroid goiter. The aim of the study was to define the diagnostic importance of reflexometry in subclinical disorders of thyroid function and to assess the relationships between metabolic derangements and the duration of the Achilles reflex. Changes in the duration were shown to correspond to disorder of thyroid function. In 76% of the cases reflexometry brought about the correct assessment of the patient's thyroid status. A significant conformity of the levels of TSH, T3, T4 to the duration of the Achilles reflex was shown.  相似文献   
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In this study, the effects of interoceptive stress on the indices of free-radical oxidation and the corticosterone contents in the brain and blood of male rats were examined. In addition, we studied the effects of the GABA-like nootropic drug calcium hopanthenate and panthenol on these indices after stress. Interoceptive stress was induced by intraperitoneal injection of bacterial lipopolysaccharide and the studies were performed 24 h after injection. The derivatives of pantothenic acid substantially attenuated corticosterone accumulation in the hippocampus after interoceptive stress induced by systemic immune challenge but did not prevent a stress-induced increase in the level of substances that reacted with thiobarbituric acid in the blood of the animals.  相似文献   
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BackgroundUnder nutrition is a problem of severe magnitude in low income countries like Nigeria. Adolescent school children might also be vulnerable. The dearth of data hinders planning of school health and nutrition programmes for school children.ObjectiveTo determine the prevalence of stunting, thinness; vitamin A and iron deficiencies among adolescent students in Nsukka urban, Nigeria and to determine factors that are associated with these nutritional problems.MethodsA total of 400 participants were randomly selected from 717 students aged 12 – 18 years in 3 randomly selected secondary schools. Questionnaires, anthropometric measurements, and blood analyses were the data collection methods employed.ResultsThe prevalence of stunting was 33.3% and thinness 31.0%. Neither overweight nor obesity was observed. While 64.0% were anaemic; 44.0% had vitamin A deficiency (VAD). A total of 48.0% had both anaemia and stunting, 42% had VAD + thinness; while 40% had anaemia + VAD. Household income was a predictor of vitamin A status. Children from medium/high income households had higher odds of having VAD than those from low income households (AOR=0.14; 95% CI=0.031, 0.607; P=0.009). Household income (AOR=0.12; 95% CI=0.021, 0.671; P=0.016), and age (AOR=0.09; 95% CI=0.014, 0.587; P=0.012) were independent determinants of height-for-age status.ConclusionAmong urban adolescent students in Nigeria, stunting, thinness, anaemia and VAD were problems of public health significance. Age and household monthly income played major roles.  相似文献   
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