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991.
OBJECTIVE: The study aim was to assess the prevalence of Helicobacter pylori infection in Egyptian schoolchildren and its effect on growth parameters. DESIGN: A cross-sectional population-based study was conducted among 286 schoolchildren (168 boys and 118 girls), with a mean age of 11.04 +/- 0.19 years, to determine the prevalence of H. pylori. The presence of the bacterium was assessed using the [13C]urea breath test. Relevant personal and socio-economic data on risk factors for infection were collected. Height and weight were analysed in relation to H. pylori infection. RESULTS: The overall prevalence of H. pylori infection was 72.38%. Attending school in a socially deprived area and residing in an overcrowded home were the major risk factors for infection. Differences between infected and non-infected children were significant with regard to body weight and height (weight: 39.5 +/- 1.0 vs. 44.6 +/- 1.8 kg, P = 0.05; height: 139.9 +/- 1.3 vs. 144.2 +/- 2.1 cm; P = 0.009). The number of children (both boys and girls) falling below the 5th percentile of height-for-age was significantly higher in infected than non-infected children (P = 001), similarly for Z-scores for height-for-age below -2.0 (P = 0.003). CONCLUSION: The results demonstrate not only that the prevalence of H. pylori infection is extremely high among Egyptian schoolchildren, but also that the adverse effects of the infection reach far beyond the stomach. Evidence of the burden of infection on growth failure is presented. 相似文献
992.
OBJECTIVES: To investigate the prevalence of anaemia and subclinical vitamin A deficiency among adolescent schoolboys in Dhaka City, Bangladesh, and to identify factors related to anaemia and vitamin A status.DESIGN: A cross-sectional study.SETTING: Government high schools in Dhaka City, Bangladesh.SUBJECTS AND METHODS: A total of 381 boys, aged 11-16 years, from 10 schools in Dhaka City participated in the study. Socio-economic, anthropometric and dietary data were collected. Haemoglobin and serum retinol (vitamin A) concentrations were determined.RESULTS: Seven per cent of the boys were anaemic and 22% had serum vitamin A levels below the adequate level of 1.05 micromol l(-1), with only 1.5% having subclinical vitamin A deficiency (<0.70 micromol l(-1)). Food frequency data revealed poor dietary habits. Multiple regression analysis showed that age, body mass index (BMI), parents' occupation, serum vitamin A level and frequency of intakes of meat and fruit were significantly independently related to haemoglobin level. The overall F-ratio (13.1) was highly significant (P<0.000) and the adjusted R(2) was 0.192. For serum vitamin A, BMI, father's education, per capita expenditure on food, haemoglobin concentration and frequency of intake of vitamin A-rich fruit were found to be significantly independently related. The overall F-ratio (14.5) was highly significant (P<0.000) and the adjusted R(2) was 0.186.CONCLUSION: The data show that adolescent schoolboys in Dhaka City have anaemia and inadequate vitamin A status, although the extent of the problems is lower than in other population groups in the country. Sociodemographic and dietary factors appear to have important relationships with anaemia and vitamin A status of these boys. 相似文献
993.
Parvaiz Ahmad Mohammed Nasser Alyemeni Leonard Wijaya Pravej Alam Mohammad Abass Ahanger Saud A. Alamri 《Archives of Agronomy and Soil Science》2017,63(13):1889-1899
We examined the role of jasmonic acid (JA) in faba bean under cadmium (Cd) stress, which reduces the growth, biomass yield, leaf relative water content (LRWC) and pigment systems. Hydrogen peroxide (H2O2) and lipid peroxidation (malondialdehyde [MDA]) levels increased by 2.78 and 2.24-fold, respectively, in plants under Cd stress, resulting in enhanced electrolyte leakage. Following foliar application to Cd-treated plants, JA restored growth, biomass yield, LRWC and pigment systems to appreciable levels and reduced levels of H2O2, MDA and electrolyte leakage. Proline and glycine betaine concentrations increased by 5.73 and 2.61-fold, respectively, in faba bean under Cd stress, with even higher concentrations observed following JA application to Cd-stressed plants. Superoxide dismutase, catalase, ascorbate peroxidase and glutathione reductase levels rose by 87.47%, 130.54%, 132.55% and 37.79%, respectively, with Cd toxicity, with further enhancement of antioxidant activities observed following foliar application of JA. Accumulation of Cd in roots, shoots and leaves was also minimized by external supplementation of JA. In conclusion, JA mitigates the negative impacts of Cd stress in faba bean plants by inhibiting the accumulation of Cd, H2O2 and MDA, and by enhancing osmolyte and antioxidant activities that reduce oxidative stress. 相似文献
994.
Sahiner Nurettin Farooq Muhammad Rehman Saif ur Sagbas Selin Sahiner Mehtap Siddiq Mohammad Aktas Nahit 《Water, air, and soil pollution》2017,228(10):1-16
Water, Air, & Soil Pollution - Sustainable groundwater quality has become a major concern for the agro-based country like Bangladesh. Integrated approaches of various irrigation water quality... 相似文献
995.
996.
Togha Jenabi Hojjatollah Saeidi Mohammad Reza Rahiminejad 《Genetic Resources and Crop Evolution》2011,58(4):497-505
The mountain rye Secale strictum is native to the Middle East and is the progenitor of the cultivated rye. Regarding lack of information about the genetic
diversity of this species in Iran, this study was aimed to evaluate its genetic variation and to examine the patterns of diversity
related to the varieties and geography. Fifteen wheat and rye derived microsatellite markers were used to achieve this aim.
High levels of diversity, with an average number of 6.1 alleles per locus (ranging up to 11) and high level polymorphism with
polymorphism rate averaging 0.624 (between populations) and 0.357 (within populations) were observed among 125 individuals
from 19 populations collected from various regions of Iran. The Northwestern populations showed the highest and the Northern
populations showed the lowest polymorphism and diversity. One population of the Northwest of the country was notably closer
in its allele range to the S. cereale accessions used as outgroup. No taxon or geographic specific marker was detected, suggesting high gene flow between the populations,
however some groupings which can be related to the geographic regions and varieties, were evident. The analysis of molecular
variance attributed same portions of genetic diversity to the within and between populations with no significant variation
among different geographic regions. The results of this study indicated that the Iranian genepool of Secale strictum is valuable to search for new useful alleles for crop improvement. 相似文献
997.
998.
Chrome electroplating wastes were collected from two industrial sites and analyzed for color, turbidity, pH, alkalinity, sulfate, chloride, N-ammonia, N-nitrate, N-nitrite, acid hydrolyzable P, dissolved oxygen, biochemical oxygen demand, chemical oxygen demand, chromate and chromium(VI). The effect of these wastes on saprophytic and nitrifying bacteria was studied with varying concentrations of the waste using sucrose substrate as a source of C chain for microorganisms. The use of clay sand mixtures as adsorbents for chromate and chromium(VI) was investigated. Mixtures high in clay content were found to be suitable media for the removal of Cr from the wastes. The clay used was characterized by determination of the following parameters: pH, electrical conductivity, water soluble salts, osmotic pressure, cation exchange capacity, CaCO3 and organic matter. 相似文献
999.
Salehi?Mohammad?M.?Email author David?R.?Smith 《Journal of Agricultural, Biological & Environmental Statistics》2005,10(1):84-103
Designing an efficient sampling scheme for a rare and clustered population is a challenging area of research. Adaptive cluster
sampling, which has been shown to be viable for such a population, is based on sampling a neighborhood of units around a unit
that meets a specified condition. However, the edge units produced by sampling neighborhoods have proven to limit the efficiency
and applicability of adaptive cluster sampling. We propose a sampling design that is adaptive in the sense that the final
sample depends on observed values, but it avoids the use of neighborhoods and the sampling of edge units. Unbiased estimators
of population total and its variance are derived using Murthy’s estimator. The modified two-stage sampling design is easy
to implement and can be applied to a wider range of populations than adaptive cluster sampling. We evaluate the proposed sampling
design by simulating sampling of two real biological populations and an artificial population for which the variable of interest
took the value either 0 or 1 (e.g., indicating presence and absence of a rare event). We show that the proposed sampling design
is more efficient than conventional sampling in nearly all cases. The approach used to derive estimators (Murthy’s estimator)
opens the door for unbiased estimators to be found for similar sequential sampling designs. 相似文献
1000.
Moh Tariq Amir Khan Mohd Asif Faryad Khan Taruba Ansari Mohammad Shariq 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2020,70(6):507-524
ABSTRACT This review deals with the mechanism of antagonistic action of bacterial and fungal biocontrol agents such as the production of antibiotics, siderophores, enzyme secretion, competition for nutrition, plant growth promotion by rhizosphere microorganism. The utilisation of synthetic pesticides has been the predominant control processor for diseases brought about by phytopathogenic microorganisms. Notwithstanding, their open and improper application in intensive agriculture has realised issues that have prompted ecological contamination, considerable residues in agricultural products and phytopathogen resistance. They are likewise disrupting the quantity of beneficial microorganism which is available in the soil and capable of expanding soil fertility. Along these lines, there is a need to look through the option of synthetic pesticides that are safe, environmental and monetarily feasible to confront this problem. Biocontrol agent’s utilisation is the best alternative method to control the different kinds of diseases, such as nematode infestation, fungal pathogen and bacterial pathogen. Nowadays, biocontrol agents assume a significant role in the field of agriculture. It is a financially savvy, environment-friendly and inhibits the advancement of pathogenic microorganism sustainably. This review emphasises the role of biocontrol agents against different pathogenic microorganisms and their significance potentiality to improve plant growth and enhance defence system of plants. 相似文献