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41.
Eighteen-month-old children were tested for mirror self-recognition using the classic rouge test or an alternative procedure, for social contingency awareness by being closely imitated for a long time, and for the capacity for communication by synchronic imitation. The classic mirror rouge test was shown to produce false negatives. Most recognizers and nonrecognizers became aware of being imitated and imitated the activity of a model, but only recognizers engaged in sustained synchronic imitation of the model. The results support our hypothesis that self-recognition and spontaneous perspective-taking develop in close synchrony because both require a capacity for secondary representation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
42.
Cerebral palsy (CP) is classified as a static encephalopathy. CP is a nonprogressive disorder affecting posture and movement and is commonly associated with a spectrum of developmental disabilities. Serial testing of physiological function can provide a quantitative assessment of improvement or decline in the condition of the patient. Furthermore, there are increasing numbers of children with disability who are involved in athletic activity, and the need for physiological feedback to the disabled athlete and coach is the same as for able-bodied individuals. It is acknowledged that children and adolescents with CP have a lower maximal oxygen consumption (VO2max) compared with their able-bodied peers. Children with CP also have distinctly subnormal values for peak anaerobic power and muscular endurance of the upper and lower limbs. Irrespective of the scaling method used (absolute or relative), when compared with normal data from healthy controls, children with CP scored between 2 and 4 standard deviations below the expected mean value for power. Gait abnormalities in children with CP have been shown to increase submaximal walking energy expenditure almost 3-fold compared with healthy children. Assessment of the metabolic cost alone is important but does not provide any information on the mechanisms giving rise to the high energy cost of locomotion in children with CP. Hence, a multidisciplinary (kinetic, kinematic and electromyographic) approach is an important noninvasive tool for studying some of the underlying mechanisms responsible for abnormal gait and elevated energy costs. A certain level of muscle co-contraction is necessary for achieving joint stability during locomotion, particularly at the ankle and knee. There appears, however, to be a co-contraction threshold beyond which there are associated elevated metabolic costs during locomotion in children with CP.  相似文献   
43.
Genetic recombination was used in Drosophila melanogaster to isolate P elements, inserted at the telomeres of X chromosomes (cytological site IA) from natural populations, in a genetic background devoid of other P elements. We show that complete maternally inherited P repression in the germline (P cytotype) can be elicited by only two autonomous P elements at 1A and that a single element at this site has partial regulatory properties. The analysis of the surrounding chromosomal regions of the P elements at 1A shows that in all cases these elements are flanked by Telomeric Associated Sequences, tandemly repetitive noncoding sequences that have properties of heterochromatin. In addition, we show that the regulatory properties of P elements at 1A can be inhibited by some of the mutant alleles of the Su(var)205 gene and by a deficiency of this gene. However, the regulatory properties of reference P strains (Harwich and Texas 007) are not impaired by Su(var)205 mutations. Su(var)205 encodes Heterochromatin Protein 1 (HP1). These results suggest that the HP1 dosage effect on the P element properties is site-dependent and could involve the structure of the chromatin.  相似文献   
44.
Our objective was to determine the effect of level and chemical form of dietary selenium on productivity of beef cows, concentrations of triiodothyronine (T3), and thyroxine (T4) in plasma, and immunoglobulins (IgG and IgM) in plasma and colostrum of cows. Pregnant cows (n = 60) were randomly allocated among four dietary treatments of 20, 60, or 120 ppm Se as selenite and 60 ppm as selenomethionine from selenized yeast (SeY) in salts offered free-choice. Treatments began 90 d prepartum and continued through the second parturition. Treatments did not affect the final body weights of cows or birth weights or weaning weights of calves. At parturition, cows given salt with 20 ppm Se as selenite had lower (P < . 05) concentrations of Se in blood than cows with access to higher-Se salts. Treatments affected (P < .01) the concentration of T3 and the ratio of T3:T4 in plasma of cows. The concentration of T3 in plasma of cows with access to salt with 20 ppm Se was 14% lower than that in cows supplemented with 60 ppm Se as selenite or SeY. Plasma IgG in cows and calves, colostrum, and Se concentrations in colostrum, casein, and whey were lowest (P < .01) for cows given salt with only 20 ppm Se. Thus, salts with concentrations of 60 and 120 ppm Se improved measures of Se status in cows and calves. Consideration should be given to the concentrations of T3 and IgG when determining the nutritional requirements for Se in cattle.  相似文献   
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Triatoma sordida is the second species of Triatominae considered of epidemiological significance in Bolivia. Associated with Triatoma infestans in various regions, it is as yet the only triatomine species established in human dwellings in localities of Velasco province, Department of Santa Cruz. This domestication is considered as primary. Flagellate parasites were detected in 16.2% of domiciliary T. sordida and the kDNA-PCR confirmed the presence of Trypanosoma cruzi. Frequencies of T. cruzi clonets 20 and 39, common clonets in Bolivian domestic cycle (T. infestans), were established by their direct detection in feces using PCR and hybridization. These clonets present low frequencies in T. sordida and synanthropic mammals. Forty-six stocks were isolated and analysed by multilocus enzyme electrophoresis (MLEE). The MLEE showed a higher clonal diversity than in T. infestans domestic cycle and the genotypes were clustered in the two principal lineages of T. cruzi. Within each lineage, a broad variability was observed. Mixture of genotypes was mostly observed in mammals. The large diversity of T. cruzi in this cycle should be related to its sylvatic origin. Moreover, the current limited sample of stocks suggests a lineage association with specific hosts.  相似文献   
48.
In a retrospective study of 50 consecutive children with posterior fossa tumors treated at Texas Children's Hospital, Houston, Tex., in 1989-1992, we evaluated perioperative factors which might influence the development of postoperative cerebrospinal fluid leaks. Factors analyzed included the presence of preoperative hydrocephalus, the institution of cerebrospinal fluid diversion, and the method of dural closure. No statistically significant impact on subsequent cerebrospinal fluid leakage was demonstrated.  相似文献   
49.
The underlying property, its definition, and representation play a major role when monitoring a system. Having a suitable and convenient framework to express properties is thus a concern for runtime analysis. It is desirable to delineate in this framework the sets of properties for which runtime analysis approaches can be applied to. This paper presents a unified view of runtime verification and enforcement of properties in the Safety-Progress classification. First, we extend the Safety-Progress classification of properties in a runtime context. Second, we characterize the set of properties which can be verified (monitorable properties) and enforced (enforceable properties) at runtime. We propose in particular an alternative definition of ??property monitoring?? to the one classically used in this context. Finally, for the delineated sets of properties, we define specialized verification and enforcement monitors.  相似文献   
50.
A new crystalline structure of poly 4-methylpentene-1 (P4MP1), modiification named modification V, is obtained from cyclopentane solutions and gels, for polymer volume fractions between 0.01 and 0.10. The effect of the thermal history imparted to the solution is analyzed. The relation between gelation, polymorphism and existence of helical conformations of P4MP1 in solution is discussed. Modification V is tentatively indexed on the basis of an hexagonal unit cell with dimensions a = 22.17 ± 0.14 Å and c = 6.69 ±0.02 Å. The crystal transforms into modification I at 130 ± 5°C, the heat of transition being + 15 ±2 J.g?1.  相似文献   
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