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91.
Casapía M Joseph SA Núñez C Rahme E Gyorkos TW 《International journal for parasitology》2006,36(7):741-747
Malnutrition in school-age children is common in developing countries and includes both stunting and underweight. Stunting, which represents a chronic state of nutritional stress, leads to adverse health, educational and cognitive effects. Although much research is focused on preschool-age children, recent studies show both the high prevalence of stunting and the effectiveness of interventions in school-age children. The objectives of the current study were to determine the risk factors for stunting only, and stunting and underweight. A survey was conducted in 1074 grade 5 children (mean age 10 years) from 17 schools in Belen, Peru, a community of extreme poverty. Prevalence of underweight and stunting were 10.5 and 34.5%, respectively, co-prevalence was 9.3%. Based on multivariable logistic regression analyses, significant independent risk factors (odds ratio: OR) for stunting and underweight were: age (per 1 year increment) (OR=1.55; 95% confidence interval (CI): 1.33, 1.81); diarrhoea in the last week (OR=1.96; 95% CI: 1.17, 3.29) and hookworm infection (OR=1.74; 95% CI: 1.05, 2.86). Significant independent risk factors for stunting only were: age (per 1 year increment) (OR=1.51; 95% CI: 1.35, 1.70); anaemia (OR=1.98; 95% CI: 1.26, 3.11); and moderate and heavy Trichuris and Ascaris co-infection (OR=1.95; 95% CI: 1.35, 2.82). Our results indicate a high prevalence of stunting, in addition to other adverse health indicators, in the study population. Due to the interrelation between many of these health and nutrition problems, interventions at both the school and community levels, including de-worming, feeding programs and health and hygiene education, are needed to reduce malnutrition in this and other similar populations living in conditions of extreme poverty. 相似文献
92.
Surfactant protein D is an important innate host defence molecule that has been shown to interact with a variety of pathogens and to play a role in surfactant homeostasis. The aim of this study was to examine the influence of oxidation on surfactant protein D in different lung diseases. Bronchoalveolar lavage fluids (BALFs) from patients with different grade of protein oxidation were examined for changes in the primary chain and the quaternary structure of surfactant protein D. Significant changes of quaternary surfactant protein-D (SP-D) structure were detected under oxidative conditions in vitro and in vivo. The functional capacity of surfactant protein D to agglutinate bacteria was impaired by oxidation. We conclude that surfactant protein D is an important target of free radicals generated in the lungs. Host defence may be impaired due to the oxidation of surfactant protein D and may contribute to the suppurative lung diseases like cystic fibrosis (CF). 相似文献
93.
Christa Cornelis Patrick Berghmans Marc van Sprundel Jean-Claude Van der Auwera 《人类与生态风险评估》2006,12(5):963-982
The Integrated Exposure Uptake Biokinetic (IEUBK) model is frequently used to estimate blood lead concentrations of children exposed to lead. Simulations with the IEUBK model were run to estimate the blood lead concentration in children living in the vicinity of a non-ferrous plant, situated in Hoboken, Belgium. Concentrations in soil ranged from 59–2425 mg Pb/kg dm, average concentrations in house dust ranged from 234–73394 mg Pb/kg dm. Measured blood lead concentrations in children aged 2–7 years were between 3 and 35 μ g/dl. Exposure sources were indoor dust in the house and the school, outdoor dust and soil in the home surrounding and at the school's playground, and suspended dust in the air. Soil ingestion values and lead exposure from food were changed to Flemish values. The model was able to predict the measured blood lead concentrations adequately except for the lowest exposure group. Predictions showed a systematic overestimation. Analysis of the data revealed that the neighbourhood's school is an important source of exposure to lead; indoor house dust dominates exposure for children going to school outside the area, because of the high concentrations of lead in indoor dust (3 to 5 times higher than in outdoor soil). 相似文献
94.
Multiple classification performance of juvenile chimpanzees,normal children,and retarded children 总被引:1,自引:0,他引:1
Anthony D. Hall John T. Braggio James P. Buchanan Ronald D. Nadler David Karan J. Bob Sams 《International journal of primatology》1980,1(4):345-359
The cognitive capacities of juvenile chimpanzees, normal children, and retarded children were evaluated by using a nonverbal,
Piagetian-type multiple classification task. The three groups of subjects were tested with the same two by two stimulus matrix,
which was formed by combining two different colors with two different shapes. On each problem the subjects were required to
select one of four stimulus items from the response tray and place it inside the empty cell of the stimulus matrix. It was
found that the human and nonhuman primates tested were able to select objects with correct color and shape cues (C+/S+)significantly more often than the other objects with only color cues correct (C+/S-), only shape cues correct (C-/S+), or neither cue correct (C-/S-). Although the two groups of human children were able to select the C+/S+ objects about 100% of the time by the end of testing, the normal children required significantly fewer problems than the
retarded children. The juvenile chimpanzees needed significantly more problems than the human subjects before they consistently
selected the C+/S+ object on the first trial and attained a level of correct responding that was above chance. Moreover, their level of performance
did not exceed 70% correct. These data suggest that the human children (both normal and retarded) used a conceptual strategy,
while the juvenile chimpanzees employed a perceptual strategy to solve the multiple classification problems. The relationship
between language and conceptual problem-solving strategies for Piagetiantype tasks is discussed.
Portions of the data reported in this study were presented at the Annual Meeting of the Southern Psychological Association,
Atlanta, Georgia, March 15–18, 1978. 相似文献
95.
Gopinath Balakrish Nair Thandavarayan Ramamurthy Dipika Sur Takashi Kurakawa Takuya Takahashi Koji Nomoto Yoshifumi Takeda 《Microbiology and immunology》2012,56(11):789-791
During a double‐blind, randomized, placebo‐controlled probiotic trial among 3758 children residing in an urban slum in Kolkata, India, Vibrio cholerae/mimicus was detected in fecal microbiota of healthy children. The importance of this finding in the local, regional and global transmission of cholera is discussed. 相似文献
96.
Andreas Christ René Guldimann Barbara Bühlmann Marcel Zefferer Jurriaan F. Bakker Gerard C. van Rhoon Niels Kuster 《Bioelectromagnetics》2012,33(8):695-705
We investigated whether domestic and professional induction cooktops comply with the basic restrictions defined by the International Commission on Non‐Ionizing Radiation Protection (ICNIRP). Based on magnetic field measurements, a generic numerical model of an induction cooktop was derived in order to model user exposure. The current density induced in the user was simulated for various models and distances. We also determined the exposure of the fetus and of young children. While most measured cooktops comply with the public exposure limits at the distance specified by the International Electrotechnical Commission (standard IEC 62233), the majority exceeds them at closer distances, some of them even the occupational limits. The maximum current density in the tissue of the user significantly exceeds the basic restrictions for the general public, reaching the occupational level. The exposure of the brains of young children reaches the order of magnitude of the limits for the general public. For a generic worst‐case cooktop compliant with the measurement standards, the current density exceeds the 1998 ICNIRP basic restrictions by up to 24 dB or a factor of 16. The brain tissue of young children can be overexposed by 6 dB or a factor of 2. The exposure of the tissue of the central nervous system of the fetus can exceed the limits for the general public if the mother is exposed at occupational levels. This demonstrates that the methodology for testing induction cooktops according to IEC 62233 contradicts the basic restrictions. This evaluation will be extended considering the redefined basic restrictions proposed by the ICNIRP in 2010. Bioelectromagnetics 33:695–705, 2012. © 2012 Wiley Periodicals, Inc. 相似文献
97.
Sitcharungsi R Ananworanich J Vilaiyuk S Apornpong T Bunupuradah T Pornvoranunt A Nouanthong P Phasomsap C Khupulsup K Pancharoen C Puthanakit T Shearer WT Benjaponpitak S;HIV-NAT Study Group 《Microbiology and immunology》2012,56(2):117-122
Knowledge of what constitute normal serum immunoglobulin (Ig) concentrations are important for the diagnosis of immunologic disorders. Data on normal Ig evaluated by nephelometry are limited in healthy Asian children, none being available for Thai children. One hundred and forty-eight healthy Thai children aged 2-15 years were tested for serum immunoglobulins G, A, M, G1, G2, G3, and G4 (Ig G, A, M, G1, G2, G3, and G4) by nephelometry. Sixty-three percent were girls of median interquartile range age 6.9 (4.8-9.7) years. The geometric means for each Ig were summarized and categorized by age. Statistical analyses were used to compare Igs between sexes and age groups, and to compare IgG in this study with data from other published studies. The average ratios of IgG subclasses/IgG for Ig G1:2:3:4 were 66:22:5:7%. IgG, IgA, IgG2, and IgG3 concentrations showed a gradual increase with increasing age. There were no significant sex differences for any immunoglobulin isotype (P= 0.971). Our mean IgG concentration was lower than that measured by the radial diffusion method in healthy Thai children (P < 0.05). In all age groups, the mean IgG concentration in our study was significantly higher than that reported in Turkish and USA children, evaluated by the nephelometric and radial diffusion techniques, respectively (both P < 0.001). This study provides information about normal Ig concentrations measured by nephelometry in healthy Asian children and illustrates the importance of ascertaining normal Ig values for age- and ethnic-matched controls using the same assay to diagnose immunologic disorders correctly. 相似文献
98.
Holster IL Vila AM Caudri D den Hoed CM Perez-Perez GI Blaser MJ de Jongste JC Kuipers EJ 《Helicobacter》2012,17(3):232-237
Background: The prevalence of Helicobacter pylori in Western populations has steadily decreased. This has been suggested as one of the factors involved in the recent increase of asthma and allergy. Some studies have reported a negative association between H. pylori and asthma and allergy, but data are inconsistent and there are a few studies in children. Aim: We investigated whether the prevalence of H. pylori was associated with asthma symptoms, allergic rhinitis, and atopic dermatitis in childhood. Methods: We determined IgG anti‐H. pylori and CagA antibodies in serum of Dutch children, who took part in the PIAMA birth cohort study. Serum was collected from 545 children, aged 7–9 years (Dutch ethnicity 91.5%). Symptoms of asthma and atopy were assessed by yearly questionnaires. Chi‐square tests and logistic regression were used. Results: We found 9%H. pylori and 0.9% CagA seropositivity. Twelve (5.9%) children with reported wheezing ever were H. pylori positive, compared to 37 (10.9%) of the non‐wheezers (p = .05). No significant differences in H. pylori prevalence were found between children with or without allergic rhinitis (8.5% vs 9.5%), atopic dermatitis (8.7% vs 9.2%), and physician‐diagnosed asthma (7.1% vs 9.4%). Multivariate analysis showed no significant associations between H. pylori seropositivity and wheezing (OR 0.52; 95% CI 0.25–1.06), allergic rhinitis (OR 0.96; 95% CI 0.51–1.81), atopic dermatitis (OR 1.05; 95% CI 0.56–1.98) or physician‐diagnosed asthma (OR 0.87; 95% CI 0.37–2.08). Conclusion: We found a borderline significantly lower H. pylori seropositivity in children with wheezing compared to non‐wheezers, but no association between H. pylori serum‐antibody status and allergic rhinitis, atopic dermatitis, or asthma. 相似文献
99.
目的对手工法双相血培养瓶和BACTEC9120全自动血培养仪的阳性率作回顾性分析。方法将血液标本同时接种双相血培养基和BACTEC9120全自动血培养仪配套血瓶中,将阳性结果移种血平板,如为阴性再移种巧克力平板。结果370例血培养,双相血培养瓶阳性25例,阳性率为6.76%(25/370),树脂需氧(儿童)瓶BACTEC9120报警显示阳性59例,阳性率为15.9%(59/370),阳性标本移种到血平板及巧克力平板阳性54例,阳性率为14.6%(54/370),假阳性5例,假阳性率为1.4%(5/370),共有29例树脂需氧(儿童)瓶阳性,而双相血培养瓶为阴性,P〈0.001。结论BACTEC9120全自动血培养仪提高阳性率,缩短阳性的报告时间优于传统的双相血培养基。 相似文献
100.
GABRIELLE A. CARLSON 《World psychiatry》2012,11(3):146-152
Issues complicating the differential diagnosis of bipolar disorder in young
people are discussed. They include: a) the subtype of bipolar disorder being
considered; b) the person’s age and stage of development; c) whether
one views bipolar disorder more conservatively, requiring clear episodes that
mark a distinct change from premorbid levels of function, or more liberally,
focusing for instance on severe irritability/explosive outbursts as the mood
change; d) who is reporting manic symptoms, and whether symptoms are past
and must be recalled or current and more likely to be observed; e) impact
of family history. The diagnosis of mania/bipolar I disorder may not become
clear for a number of years. This is an impairing disorder, but so are the
conditions from which it must be distinguished. Family history may increase
the odds that certain symptoms/behaviors are manifestations of bipolar disorder
but it does not make the diagnosis. Until there are biomarkers that can confirm
the diagnosis, and treatments unique to the condition, it is wise to make
a diagnosis of bipolar disorder in children and adolescents provisionally
and keep an open mind to the likelihood that revisions may be necessary. 相似文献