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1.
The manifestations of the epidemic process in respiratory syncytial (RS) virus infection induced by the strains of the infective agent, differing in their capacity for reproduction at 39 degrees and 37 degrees C and in their sensitivity to antibodies, were compared. The observation of children in a group (about 80 children simultaneously) with the systematic serological and virological examination of sick and healthy children was the main method in this investigation. The circulation of RS viruses with greater capacity for reproduction at 39 degrees and 37 degrees C and lesser sensitivity to antibodies, i.e. viruses with greater virulence, was accompanied by the increased intensity of manifestations of the epidemic process. An increase in the heterogeneity of RS virus populations isolated at the same period of observation was accompanied by the intensification of the epidemic process, which was manifested by increased morbidity rate and a higher level of contamination in children, an increase in the incidence of outbreaks and in the frequency of RS virus reinfection.  相似文献   

2.
To study the immune responsiveness of children in the measles vaccinal process, the cytochemical methods for the identification of immunocompetent cells have been used. The investigations have been made in children aged 1.5-4 years, immunized with live measles vaccine prepared from strain l-16. The results of these investigations indicate that the development of specific antiviral postvaccinal immunity is characterized by transitory changes in the populations of T-, B- and O-lymphocytes; such changes are accompanied by not only quantitative, but also qualitative changes of individual populations.  相似文献   

3.
In a small agropastoral Aymara community called Wariscata in the Andean Altiplano of Bolivia, anthropometric measurements were made in 1988. In comparison with those of published data for the other rural and urban Andean populations (Aymara, Quechua and Mestizo at high and low altitudes), the Aymara children of Wariscata were taller and heavier than other rural high altitude native children, but similar in height to urban high altitude children. This is possibly due to secular change of growth accompanied with nutritional improvement that has taken place in recent years. Chest width and depth had similar values to those in other Aymara children. But, Aymara children in Wariscata of both sexes had smaller chest dimensions (depth and width) than those of Quechua children. However, these ethnic differences in chest dimensions were not reflected in the adult Aymara and Quechua, suggesting different process of chest growth in Aymara and Quechua populations.  相似文献   

4.
The phenomenon of magical contagion – the unobserved passage of properties between entities that come into physical contact – was described by anthropologists over a century ago, yet questions remain about its origin, function, and universality. Contagion sensitivity, along with the emotion of disgust, has been proposed to be part of a biologically-evolved system designed to reduce exposure to pathogens by increasing the avoidance of “contaminated” objects. Yet this phenomenon has not been studied using systematic psychological comparison outside of industrialized populations. Here we document contagion sensitivity in two culturally, geographically, and economically distinct populations with little exposure to Western biomedicine and formal education: the Hadza hunter-gatherers of Tanzania and Tannese subsistence-agriculturalists of Vanuatu. In both populations, a majority of individuals rejected familiar and palatable foods when contaminating items touched the food but were subsequently removed. The Tannese children in our study showed a similar response, consistent with previous research with Western children. Our data support the proposal that contagion sensitivity is universal in human populations.  相似文献   

5.
Iu E Dubrova  V A Shenin  K R Sedov 《Genetika》1989,25(10):1878-1883
Variation of 5 anthropometric traits at birth in groups of normal children who had suffered from acute respiratory diseases during their first year of life was studied in Russian migrant and native population inhabiting the Western area of Baikal-Amur Railway. It was shown that affected children from migrant and native population had lower average values of all traits, as compared with normal children. In order to reduce the number of variable, the principal component analysis was applied. Stronger similarity was found between groups of normal children from native and migrant populations than between normal children and affected children from one population. This can be the evidence of the formation of similar adaptive norm for children from both Russian populations.  相似文献   

6.
A detailed analysis of chronological intervals typical of reproduction process has been carried out in rural Khakassian populations to reveal the mechanisms of natural selection and gene drift. It is shown that the process of reproduction is connected with cultural traditions and economical activity of a population under study. The main characteristics of reproductive family behavior (the whole number of children and sex ratio, birth interval ect.) play a very important role in family and kin relationships, age, sex and marriage-migration structure of the population.  相似文献   

7.
The growth of IQ among Estonian schoolchildren from ages 7 to 19   总被引:2,自引:0,他引:2  
The Standard Progressive Matrices test was standardized in Estonia on a representative sample of 4874 schoolchildren aged from 7 to 19 years. When the IQ of Estonian children was expressed in relation to British and Icelandic norms, both demonstrated a similar sigmoid relationship. The youngest Estonian group scored higher than the British and Icelandic norms: after first grade, the score fell below 100 and remained lower until age 12, and after that age it increased above the mean level of these two comparison countries. The difference between the junior school children and the secondary school children may be due to schooling, sampling error or different trajectories of intellectual maturation in different populations. Systematic differences in the growth pattern suggest that the development of intellectual capacities proceeds at different rates and the maturation process can take longer in some populations than in others.  相似文献   

8.
This study compares the growth characteristics of populations of Tibetan origin living in Nepal to high altitude populations of Peru and Ethiopia. Measurements were made on two groups of children, a sample of Sherpas living in the Everest region of northeast Nepal at elevations in excess of 3500 m, and a sample of Tibetan children living in Kathmandu at an altitude of 1000 m. Although the Tibetan children showed some growth advancement over the highland sample of Sherpas, the differences were less than might have been expected on the basis of work carried out in Peru, where long established high altitude populations live at similar elevations to those of Himalayan populations. In particular, some growth trends seen in Andean populations, such as the increased diameter of the chest wall, are not seen in populations of Tibetan origin. It is suggested that genetic influences may exert a stronger effect on the growth of high altitude populations than hitherto believed.Presented the Seventh International Biometeorological Congress, 17–23 August 1975, College Park, Maryland, USA.  相似文献   

9.
Recent anthropological findings document how certain lowland South American societies hold beliefs in 'partible paternity', which allow children to have more than one 'biological' father. This contrasts with Western beliefs in 'singular paternity', and biological reality, where children have just one father. Here, mathematical models are used to explore the coevolution of paternity beliefs and the genetic variation underlying human mating behaviour. A gene-culture coevolutionary model found that populations exposed to a range of selection regimes typically converge on one of two simultaneously stable equilibria; one where the population is monogamous and believes in singular paternity, and the other where the population is polygamous and believes in partible paternity. A second agent-based model, with alternative assumptions regarding the formation of mating consortships, broadly replicated this finding in populations with a strongly female-biased sex ratio, consistent with evidence for high adult male mortality in the region. This supports an evolutionary scenario in which ancestral South American populations with differing paternity beliefs were subject to divergent selection on genetically influenced mating behaviour, facilitated by a female-biased sex ratio, leading to the present-day associations of female control, partible paternity and polygamy in some societies, and male control, singular paternity and monogamy in others.  相似文献   

10.
Traditional and original methods of EEG analysis were used to study the brain electrical activity maturation in 156 children and adolescents from 7 to 17 years old who represented the native (Koryaks and Evenks) and newcomers' populations living in severe climatic and geographic conditions of the Russian North-East. New data revealing age-, sex- and ethnic-related features in quantitative EEG parameters are presented. Markers are obtained that characterize alterations in the structure of interaction between different EEG rhythms. The results demonstrate age-dependent transformation of this structure separated in time for both different cortical areas and different EEG frequency bands. These alterations show time lag from 2 to 3 years in children of native population compared to the newcomers. The revealed differences are assumed to reflect geno-phenotypical features of morpho-functional CNS development in children of the native and newcomers' population that depend on strong adaptation tension for extreme environmental conditions.  相似文献   

11.

Background

Transthoracic echocardiography is the primary imaging modality for the diagnosis of right ventricular (RV) involvement in congenital and acquired heart diseases. There is increasing recognition of the contribution of RV dysfunction in heart diseases affecting children and adolescents, but there is insufficient information on reference intervals for the echocardiographic measurements of the right heart in children and adolescents that represent all the continental populations of the world.

Objective

The aim of this systematic review was to collate, from published studies, normative data for echocardiographic evaluation of the right heart in children and adolescents, and to identify gaps in knowledge in this field especially with respect to sub-Saharan Africans.

Methods

We performed a systematic literature search to identify studies of reference intervals for right heart measurements as determined by transthoracic echocardiography in healthy children and adolescents of school-going age. Articles were retrieved from electronic databases with a combination of search terms from the earliest date available until May 2013.

Results

Reference data were available for a broad range of variables. Fifty one studies out of 3096 publications were included. The sample sizes of the reference populations ranged from 13 to 2036 with ages varying from 5 to 21 years. We identified areas lacking sufficient reference data. These included reference data for determining right atrial size, tricuspid valve area, RV dimensions and areas, the RV % fractional area change, pulmonary artery pressure gradients and the right-sided haemodynamics, including the inferior vena cava dimensions and collapsibility. There were no data for sub-Saharan African children and adolescents.

Conclusion

Reliable reference data are lacking for important echocardiographic measurements of the RV in children and adolescents, especially for sub-Saharan Africans.  相似文献   

12.
The growth and somatotype patterns of Manus children, Territory of Papua and New Guinea, reflected in anthropometric measurements and somatotype photographs, is reported for 438 children, ranging from 15 months of age to maturity. Somatotype distributions and individual somatotype photographs indicate little difference between boys and girls from age 1 to 4 years; between age 5 and 9 years boys shift toward higher second component ratings; between age 10 and 18 years boys shift toward higher second and third component ratings, while girls shift toward higher first and third component ratings. Four sample somatotype photographs are representative of the population at age 10 and 14 years, and show age and sex characters easily noted visually. Comparison of height, weight and subscapula skinfold values show that the Manus children resemble the Kaiapit and Bundi children of the New Guinea highlands populations reported by Malcolm in the form of their growth curves but not in growth rates. Manus children grow more slowly than the British, but faster than the Kaiapit and Bundi children. While low skinfold values and height/weight ratios derived from means for height and weight suggest somatotypic similarity of the Manus, Kaiapit and Bundi populations, somatotype photographs are needed for confirmation. Lacking historical information and genetic evidence, we can speculare that diet, nutrition, climate and perhaps physical activity are factors which influence the growth patterns of these populations. The protein intake derived from fish and other seafood may be an important factor in the relatively fast growth and earlier maturation of the Manus. Malcolm thinks that low protein intake plays an important role with the Kaiapit and Bundi, but does not rule out survival value of slow growth and short stature.  相似文献   

13.
Radiographs of the left hand of 594 children from Ibadan, Nigeria were inspected for skeletal anomalies to determine differences in the incidence of cone and ivory epiphyses for the rich and poor children and differences in incidence for four hemoglobin types. Ivory epiphyses ovvurred more often in children in the lower socio-economic class and children with hemoglobin AA. The cone epiphyses observed in Hb SS children were primarily a result of bone infarcts, while cones in children of other hemoglobin types appeared to be normal variants. The incidence of ivory epiphyses was higher in the Nigerian children than in American black children in the Ten-State Nutrition Survey. The incidence of cone epiphyses was much lower than those reported for other normal populations.  相似文献   

14.
Two studies examined children's reasoning about biological kinds in populations that vary in formal education and direct experience with the natural world, a Western (urban U.S.) and a Non-Western population (Tanna, Vanuatu). Study 1 examined children's concepts of ecological relatedness between species (N = 97, 5–13-year-olds). U.S. children provided more taxonomic explanations than Ni-Vanuatu children, who provided more ecological, physiological, and utility explanations than U.S. children. Ecological explanations were most common overall and more common among older than younger children across cultures. In Study 2, children (N = 106, 6–11-year-olds) sorted pictures of natural kinds into groups. U.S. children were more likely than Ni-Vanuatu children to categorize a human as an animal and the tendency to group a human with other animals increased with age in the U.S. Despite substantial differences in cultural, educational, and ecological input, children in both populations privileged ecological reasoning. In contrast, taxonomic reasoning was more variable between populations, which may reflect differences in experience with formal education.  相似文献   

15.
As assessed by changes in the erythrograms asymmetry coefficient, selectivity of the strophantin effect on cell populations with different mobility and age specifics of reciprocal responses, was revealed in adult subjects and in children. The data obtained suggest existence of difference in quality of functional condition of the erythrocytes with normal as well as reduced mobility in children and in adults.  相似文献   

16.
Medico-genetical examination of children from 6 invalid houses, 2 asylum houses, 3 internate schools and 1 house for deaf and feeble-hearing children as well as from the internate school for children with poor vision was undertaken in Krasnodar district. 10.6% of the children were found to have chromosomal abnormality, 26.5%--multifactorial pathology and 62.9% of children were affected by monogenic diseases. The spectrum of diseases covers 20 forms, 8 of them being autosomal-dominant, 10--autosomal-recessive and 2--X-linked forms. A "selective" method presented in this article for revealing patients affected by genetical diseases in specialised institutions permitted to evaluate a portion of the patients having been not identified when using the "survey" expeditional method of population--epidemiological study of the district population. This portion constitutes 19%. The more accurate values of genetic load in populations of Krasnodar district were obtained, being 1.06-0.06 for autosomal-dominant, 0.78-0.05 for autosomal-recessive and 0.38-0.05 for X-linked diseases per thousand.  相似文献   

17.
We examined dermatoglyphic prints of children in 11 Hungarian and 5 Gypsy population samples (collected from 1,998 children). We compared Hungarian and Gypsy populations based on 22 finger and 24 palmar traits. In univariate comparisons the two ethnic groups differed significantly in half of the studied variables (9 finger and 14 palmar traits). We used several types of multivariate analyses of the studied traits to separate the population samples. Homogeneity analysis and discriminant analysis proved to be the most appropriate method to distinguish the populations, whereas a principal components analysis was less adequate. Multivariate analyses were conducted separately for both finger and palmar traits. Although the differences between the populations were more pronounced for palmar traits, in our study Hungarian and Gypsy populations showed the best separation when finger and palmar traits were combined for analysis, except in the principal components analysis. As expected, the Hungarian and Gypsy populations separated definitely in most statistical analyses; the main reason for this is the different origins of the two ethnic groups. The existence of the difference also shows that admixture between Hungarians and Gypsies has been small despite their living beside one another for several centuries.  相似文献   

18.
The results of integrated study of the genetic structure and prevalence of monogenic hereditary diseases (MHDs) in the child population of three republics of Russia are summarized. Eight raions (districts) of the Republic of Bashkortostan and six districts of each Republic of Chuvashia and Republic of Udmurtia has been surveyed. The total population surveyed was 782184 people, with children accounting for 24.67% of them (192992 children). The loads of autosomal dominant (AD), autosomal recessive (AR), and X-linked MHDs have been calculated separately for urban and rural populations; differences between individual populations in the MHD load have been found. The differentiation of subpopulations with respect to MHD prevalence is explained by differences in the degree of subdivision. The MHD spectrum in the child population of the three republics comprises 222 disease entities, including 121 AD, 83 AR, and 18 X-linked diseases. Group of highly prevalent MHDs in regional child populations have been determined. The mean fitness of MHD patients in Bashkortostan has been calculated; it is 0.87, 0.04 and 0.16 for AD, AR, and X-linked diseases, respectively. Analysis has demonstrated that the prevalence rates of MHDs in the child populations of the republics of Chuvashia, Udmurtia, and Bashkortostan are 1, 1.2, and 1.4%, respectively.  相似文献   

19.
Heritability in growth patterns of children is estimated to be between 72% and 88%. Environmental factors influence the manifestation of growth processes during the maturation process of children. Starting from the well-studied and generally accepted conclusion that growth and maturation of children mirrors the nutritional status of the population, the author provides a general overview on this problem and demonstrates that the anthropometric traits studied in growing children react quickly and sensitively to irreproducible social changes.  相似文献   

20.
The colonization efficacies of salivaricin A (SalA)-producing Streptococcus salivarius strains 20P3 and 5 were compared when given in milk to 219 children, using either 2-day or 9-day dosing regimens. Colonization levels overall were superior for strain 5, and the 9-day dosing schedule resulted in higher levels of both initial colonization and strain persistence. The indigenous streptococcal tongue populations of 20 (10.9%) of the 189 children in the 2-day trial showed markedly increased SalA-like inhibitory activity following use of the S. salivarius-supplemented milk. All 20 of these children were found to have had relatively small (<5% of total S. salivarius) indigenous tongue populations of SalA-producing S. salivarius, and the relative proportions and/or inhibitory activity of these SalA producers on the childrens' tongues increased following ingestion of the S. salivarius-supplemented milk. Because SalA is known to be strongly inhibitory to Streptococcus pyogenes, an important implication of this study is that the consumption of SalA-producing probiotic S. salivarius could potentially help to effect a sustained increase in SalA-mediated protection against S. pyogenes infection.  相似文献   

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