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1.
This study has been designed to evaluate the immunogenicity of neonatal BCG-vaccination in children at the age of 7 to 8 years, by skin test using Purified Protein Derivative (PPD), as BCG vaccination at birth is a part of routine program of immunization in our country, Iran; we decided to study its efficacy and also tried to determine if there is any correlation between PPD-test results and BCG scar size. This is a comparative study on 150 children (94 males and 56 females) at the age of 7 to 8 years, who possess neonatal-BCG scar. They were chosen from several primary schools in Tabriz-Iran, by simple random sampling and tested with 0.1 mL of 5-unit-PPD solution (a product of Iran Institute of Razi); then observations recorded. The average diameter of BCG scars were 7.03 mm in girls, 5.45 mm in boys and 6.05 for all. The diameter of induration area resulted from PPD-test after 72 h was less than 5 mm in 95.33% and 5-9 mm in 4.66% of studied children; there was no case with induration area of 10 mm or more at all. Every child who developed an induration area of 5 mm or more by PPD test, had a BCG scar with the diameter of 5 mm or more. There was a statistically meaningful direct correlation between sizes of neonatal-BCG scar and diameter of induration area after PPD-test (r = 0.21 and p = 0.008). This study shows that reactivity to PPD test (and probably immunity against tuberculosis) decreases as age increases; therefore it seems to be necessary to repeat BCG-vaccination in children at the age of entering primary school.  相似文献   

2.
Obesity subjects individuals into metabolic and endocrine disorders. Thus obesity may increase the risk of vitamin D deficiency. This text aims at studying the prevalence of vitamin D deficiency and secondary hyperparathyroidism in obese children. In a non-randomized case control study on 52 obese children (body mass index (BMI) >95th percentile) aged 4 to 16 years undertaken at the outpatient endocrine clinic of the Children Hospital at Tabriz University between 2009-2011. This study was conducted to compare the prevalence of vitamin D deficiency and secondary hyperparathyroidism in obese children compared with 57 non obese (BMI < 85th percentile). 109 children including 52 (50.5%) boys and 57 (49.5%) girls were studied. Most of case (76.9%) and control (42.1%) groups suffered from degrees of vitamin D deficiency. There was meaningful statistical difference between two groups considering to vitamin D deficiency and parathyroid hormone (p = 0.001). A negative relations was found between iPTH and vit D level (p < 0.001, r = -0.2), BMI and 25-OH vit D (p < 0.001, r = -0.2). A positive relation was observed between parathyroid hormone and BMI (p = 0.009, r = 0.1). Obese children are at high risk at vitamin D deficiency and secondary hyperparathyroidism. BMI appears to be an important risk factor for vitamin D deficiency.  相似文献   

3.
Influence of six (10, 20, 30, 40, 50 and 60%) levels of bruchids infestation on the contents of selected antinutritional factors-phytic acid, saponins, trypsin inhibitors activity (TIA) of three (chickpea, red gram, and green gram) pulses was studied. Comparisons of infested samples were made with uninfested controls of each pulse. The three antinutritional factors viz TIA, phytic acid and saponins were found to increase with the increase in the level of infestation. All the control pulse values of the phytic acid, saponins and TIA were significantly lower than those of the infested samples. Barring a few exceptions, the differences in the contents of antinutritional factors in pulses infested at different levels were significant (P<0.05).  相似文献   

4.
Asthma is a common chronic disease of childhood which causes considerable morbidity. Asthma affects 1 in 13 school-age children and is a leading cause of office and emergency department visits, hospitalizations, and school absenteeism. Estimating the prevalence of asthma in the community is important in assessing the impact of asthma at the level of population. Since the pooled prevalence of asthma in Iranian elementary school age children (6-12 years old) was not identified, we decide to conduct a meta-analysis study to estimate the prevalence of asthma in elementary school age children in Iran. In order to gather the data, we searched a number of international electronic sources such as Pub Med, Embase, science direct, and ISI for English articles, and Iranian National Knowledge Infrastructure (scientific information) sources such as Iranmedx, Iran-doc, and SID for Persian articles from February 1995 to January 2010 to access the data. We used the words childhood, asthma, prevalence, and Iranian for searching relevant papers and used a data extraction form for the extracted data. The outcome in this Meta analysis study was response to the question, "Ever had asthma", based on the ISSAC program questionnaire. Eleven relevant articles were included for the Meta analysis. The pooled prevalence for girls, boys, and the two genders was obtained as 3.2% (CI; 2.5 to 3.9%), 4.3% (CI; 3.5 to 5.1%) and 3.9% (CI; 3.2 to 4.7%), respectively. The pooled prevalence of asthma in Iranian elementary school age children is low in comparison to the other reports.  相似文献   

5.
This study was conducted to assess the herbicide savings and the cost efficiency of site-specific herbicide application strategies in comparison with other strategies based on uniform application of herbicides throughout the whole field. The specific situation considered was Sorghum halepense infested maize fields in Spain. The results from a theoretical economic model were contrasted with the information derived from a S. halepense survey conducted in 37 commercial maize fields distributed over three Spanish maize production areas. Seven application strategies were simulated: 1) no herbicide; 2) overall full-rate; 3) overall half-rate; 4) and 5) site-specific spraying infested cells with full- and half-rate, respectively; 6) and 7) site-specific spraying infested cells plus adjacent buffer areas with full- and half-rate, respectively. The simulation results showed that site-specific weed management was the most profitable strategy when S. halepense infested area ranged between 6.5 and 18.7%. This scenario was present in 22% of the surveyed fields. In fields with less than 6.5% infestation (a situation present in 51% of the surveyed fields), yield losses were slight and the most profitable strategy was using no herbicide. When the infested area ranged between 18.7 and 40.8% (19% of the surveyed fields), no significant differences were observed between the net benefits of the various strategies. Full rate herbicide applications throughout the entire field resulted in the highest net returns in fields with more than 40.8% weed infestation (8% of the surveyed fields). In these cases, the added costs of weed detection, mapping and site-specific herbicide application were not justified by the herbicide savings obtained. Likewise, herbicide savings obtained with the various strategies depended on the proportion of the field infested. Considering the high difference between site-specific treatments and uniform application of herbicides when the infested area ranged between 18.7 and 40.8%, and that no significant differences in net returns were observed in this range, site-specific treatments should be preferred. Adding a buffer area to the site-specific treatments does not seem a suitable strategy due to the considerable increases in costs and reductions in herbicide savings.  相似文献   

6.
The loss of yield resulting from infestation with potato leafhoppers,Empoasca fabae (Harris), was measured in a group of potato selections (Solatium tuberosum subsp.tuberosum). For 6 years in which 300 different clones were tested, the average loss of yield was 39%. The correlation over clones between level of infestation and percent hopperburn equaled 0.56; between level of infestation and loss of yield 0.36; and between percent hopperburn and loss of yield 0.41. Each coefficient is significant at P=0.01. Significant differences were found in levels of infestation and in percent hopperburn among the selections, but even those selections with the most resistant foliage had greatly reduced yields when infested. No selections were found that consistently produced a normal yield when infested with leafhoppers. The low level of infestation on the more resistant clones, however, may make chemical control at lower rates more effective.  相似文献   

7.
冉伟  张瑾  张新  蔺松波  孙晓玲 《茶叶科学》2018,38(2):133-139
研究了茶尺蠖幼虫为害茶树叶片对儿茶素合成途径的影响。采用3龄茶尺蠖幼虫取食茶树新梢芽下第二叶,测定了儿茶素合成相关基因的表达水平和儿茶素含量。研究结果表明,与对照相比,茶尺蠖幼虫为害后3、6、12βh显著诱导了CsANR基因的相对表达水平,且在为害后3βh和12βh达到了极显著差异。CsLAR基因在茶尺蠖为害后6βh和12βh,与对照具有显著差异。茶尺蠖幼虫为害后24βh显著诱导了没食子酸、没食子儿茶素、表儿茶素、表没食子儿茶素没食子酸酯和表儿茶素没食子酸酯含量的升高,而茶尺蠖为害后48βh仅没食子酸和没食子儿茶素的含量显著高于对照;儿茶素、表没食子儿茶素和没食子儿茶素没食子酸酯在茶尺蠖为害后24βh和48βh均没有被显著诱导。上述结果表明茶尺蠖幼虫为害提高了茶树儿茶素合成途径的代谢强度和儿茶素类化合物的积累。  相似文献   

8.
The coffee berry borer (CBB), Hypothenemus hampei Ferrari (Coleoptera: Curculionidae), is the most important coffee pest in most of the coffee growing countries. CBB females leave old dry berries after harvest and search for dry noninfested berries on the plant or on the ground to lay eggs or to use as refuge until new berries are available on the coffee trees in the following season. The CBB infestation level and emergence from berries on the ground or on the plants were evaluated in two fields post-harvest in the Spring in Brazil over two seasons. Twenty infested or noninfested berries in separate cages (250 ml plastic cups) were placed on the plants or on the ground under the tree canopy, in each field. The number of infested berries and CBB females that emerged from the infested berries were recorded weekly. CBB emergence was higher from berries on the ground than those on the coffee trees in both seasons, whereas CBB infestation was higher on coffee berries on the plants than those on the ground in season I. Insolation (hours of sunlight) and temperature were the main covariates that affected emergence and infestation by this insect. The results are discussed for monitoring CBB during the time of dispersal with implications on integrated management of this pest.  相似文献   

9.
N. Ioannou 《Potato Research》1989,32(3):331-339
Summary Field experiments during 1984–6 tested the effects of planting date on the development of aphid infestations and the spread of potato leaf roll virus (PLRV) in rogued or unrogued plots of potatoes, cv. Spunta. Plantings were made each month from December to April, the customary time for planting being February. Aphid infestation in early-planted plots was severe throughout the growing season; plots planted in February were also severely infested early in the growing season but the populations later gradually declined to undetectable levels. Nevertheless, the incidence of PLRV in the latter plots was as high as in those planted in December-January. Late-planted crops escaped aphid infestation and PLRV infection, either in part (March planting) or completely (April planting). Such crops, however, were uneconomical due to poor yields and heavy losses from potato tuber moth infestation. Roguing significantly reduced the spread of PLRV in all years but its interaction with planting date was insignificant.  相似文献   

10.
腰果园茶角盲蝽为害分布型及防治策略的研究   总被引：1，自引：1，他引：1  
通过对腰果园茶角盲蝽(Helopeltis fasciaticollis Popplius)种群消长过程为害分布型的测定及拟合其生长指数曲线,发现一年中其种群建立始于8—9月份,翌年1月份前,虫口增长缓慢,2月初起,虫口急剧增加,4—5月份是为害高峰期,6—7月份虫口自然减少,其空间构型除高峰期外,均属聚集分布,早期为Neyman核心分布。从虫口增长速度及空间构型来看,11—1月份是种群为害扩展的临界期,也是化学防治的最有利时机。为此,我们采取了定期全面调查,及早发现中心虫株(区),局部喷药(挑治)的策略,从而以最低的防治成本获得最佳的经济效益,把整个花、果期的盲蝽为害率控制在5%以下。每年收果后修枝和适当疏伐也是减轻茶角盲蝽为害的重要手段。  相似文献   

11.
A significant decrease in essential amino acids of wheat, maize and sorghum was observed due to grain infestation caused by mixed populations ofTrogoderma granarium Everts andRhizopertha dominica Fabricius (50:50). Non-essential amino acids were also adversely affected. Among the essential amino acids, maximum reduction was found in methionine, isoleucine and lysine in infested wheat, maize and sorghum grains, respectively. Lysine, with lowest chemical score in uninfested and infested grains of three cereals, is the first limiting amino acid. Insect infestation caused significant (p<0.05) reduction in the chemical score of all the essential amino acids, yet did not change the position of first and second limiting amino acids in wheat and sorghum. However, in case of maize, isoleucine became the second limiting amino acid. Infested grains also showed substantial reduction in essential amino acid index, calculated biological value and requirement index.  相似文献   

12.
Potato genotypes were evaluated for resistance to natural infestations of the potato leafhopper,Empoasca fabae (Harris), in the field. Characterization of Type A and B glandular trichomes, phenolic properties of Type A trichomes, glycoalkaloid content and composition,E. fabae adult and nymph infestation, leaf damage (hopperburn), yield, and yield reduction were determined on genotypes PI 473331 and PI 473334 (accessions ofSolatium berthaultii (Hawkes)), NY123 and Q174-2 (advanced hybrids), and Elba and Allegany (commercial cultivars). Regarding the Type A trichome, PI 473334 was most pubescent, followed by PI 473331, both had high levels of enzymatic browning; on PI 473334 no glycoalkaloids were detected, while on PI 473331 solamargine and solasonine were present. Those genotypes were the least infested by adults; moreover, nymphs were never found on their leaves. PI 473331 and Q174-2 possess Type B trichomes, the latter had levels of Type A trichome comparable to the first and to NY123, while displaying high levels of phenolic oxidation of Type A and very low levels of glycoalkaloids. Although Q174-2 had intermediate infestation ofE. fabae, it suffered a yield reduction comparable to the control cultivar Allegany. The density of Type A trichomes of NY123 was relatively low, even though the browning assay results were significantly elevated. Foliage of this genotype was found to contain the four types of glycoalkaloids studied at high levels.Empoasca fabae infestation on NY123 was intermediate, and it yielded well on infested plots, but suffered an intermediate yield reduction. Elba presented densities of Type A similar to NY123. It suffered the lowest yield reduction despite its high levels of leafhopper infestation and hopperburn. Its tolerance might be associated with its phenology, since it is a late-maturing cultivar. High scores of the modified enzymatic browning assay were correlated with high infestation and high leaf damage. Results indicated a significant correlation between leafhopper infestation and hopperburn.  相似文献   

13.
The aim of this study was to evaluate the etiology of pediatric Chronic Kidney Disease (CKD) in a tertiary care hospital in north-west of Iran. Medical records of admitted children with CKD in Children's Hospital of Tabriz from 1999 to 2009 were studied retrospectively. CKD was defined as GFR less than 60 mL min(-1) 1.73 m2 for more than 3 month. The etiology of CKD was determined by clinical, biological, radiological and histopathological examination. During 10 years 115 children including 61 boys (53%) and 54 girls (47%) were studied. The mean age of patients was 8.1 +/- 3.53 years (range: 4 months to 14 years). Urological abnormalities were the most common cause of CKD (36.5%) followed by acquired glomerular diseases (23.5%), hereditary nephropathies (21.7%), unknown etiology (9.5%) and systemic diseases (6%). The most common urologic anomaly was vesicoureteral reflux (VUR) that accounted for 24.3% of total etiologies followed by obstructive uropathies. Focal segmental glomerulosclerosis was the most frequent glomerular disease and was responsible for 13.9% of patients. Nephronophtisis, cystinosis, infantile polycystic disease and congenital nephrotic syndrome were the most frequent hereditary nephropathies in a descending order. Frequency of parental consanguinity in patients with hereditary nephropathy was significantly higher than other patients (p = 0.001). High frequency of VUR in present study compared with developed countries necessitates more efforts for improving the management and follow up of urinary tract infections.  相似文献   

14.
The effect of age of resistant potato clones,Solarium tuberosum gp.tuberosum, on infestation by potato leafhopper,Empoasca fabae (Harris), was investigated by varying the date of planting in a naturally infested fieldtest Significant differences (P < .05) in infestation levels were found among clones and among dates of planting. The responses of resistant and susceptible clones to infestation differed with date of planting. But lower levels of infestation occurred on all clones in the first 2–3 weeks of leafhopper migration on the early plantings, indicating that plant age in potatoes is a factor in host preference of potato leafhopper  相似文献   

15.
Barley (Hordeum vulgare L.) that is infested with Fusarium head blight (FHB, ‘scab’) is unsuitable for malting and brewing because it may contain mycotoxins and has unacceptable malting quality. Fungal proteinases are apparently often involved in plant-microbe interactions, where they degrade storage proteins, but very little is known about the enzymes that the fungi produce in the infected grain. We have shown previously that one plant pathogenic fungus, Fusarium culmorum, produced subtilisin- and trypsin-like enzymes when grown in a cereal protein medium. To establish whether these proteinases were also synthesized in FHB-infested barley in vivo, field-grown barley was infested as the heads emerged. Extracts were prepared from the grain as it developed and matured and their proteolytic activities were measured with N-succinyl-Ala-Ala-Pro-Phe p -nitroanilide and N-benzoyl-Val-Gly-Arg p -nitroanilide. The heavily infested barleys contained both subtilisin- and trypsin-like activities. These enzymes reacted with antibodies prepared against each of the two F. culmorum proteinases, indicating that those produced in the laboratory cultures and in the field-infested barley were the same. The presence of these proteinases correlated with the degradation of specific buffer-soluble proteins in the infested grains. These enzymes readily hydrolyzed barley grain storage proteins (C- and D-hordeins) in vitro. The presence of these Fusarium proteinases in the barley indicates that they probably play an important role in the infestation, but exactly how and when they function is not clear.  相似文献   

16.
Two cowpea varieties (Ife-brown and Kano-white varieties) were used for the study. The effects of insect infestation on the chemical composition and physicochemical properties of these cowpea seeds were studied. The proximate composition, mineral content, total starch, total soluble sugars, bulk density, fat and water absorption capacities, viscosity, gelation capacity and emulsion properties of infested cowpea varieties were compared with those of uninfested cowpeas. Effects of infestation on nitrogen solubulity and on the protein fractions were also determined. lnfestation depleted the protein, starch and soluble sugar contents of cowpeas. Oil and water absorption capacities were increased while emulsification, foam and viscosity properties were reduced. The nitrogen solubility pattern was altered. Uninfested Kano-white cowpeas (UKW) possessed better foam properties than uninfested Ife-brown cowpeas (UFB). On the other hand, UFB had better emulsification properties than UKW.  相似文献   

17.
Pheromone-baited traps are an important sampling tool in integrated pest management programmes. Studies were conducted to determine the relationship between catches of male insects in these traps, and crop infestation. Numbers of male moths of the pink bollworm, Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae), caught daily in cotton fields at the University of Arizona Cotton Research Center, Phoenix, Arizona, in gossyplure-baited traps were variable. However, average catches of male moths for 3–7 days between boll-sampling periods were strongly correlated with oviposition on cotton bolls, percentages of infested bolls and numbers of larvae per boll. Average weekly numbers of moths emerging from infested cotton were also strongly correlated with the number of males caught: the number of females emerging was strongly correlated with oviposition on cotton bolls. Insecticide applications of carbaryl and fenvalerate reduced catches of male moths of pink bollworm in gossyplure-baited traps compared with catches in traps in untreated fields (average 56%). However, 13–48 male moths/trap per night were caught in the treated fields after applications. Thus, scheduling treatments on the basis of male moth trap catches, except for the initial treatment, was not feasible. Small field sizes, moth immigration and/or continuing emergence from the infested cotton in the fields may have obscured the impact of the insecticide treatments on adult moth populations.  相似文献   

18.
Protein quality of sorghum grains having 25, 50 and 75% infestation caused by mixed population ofTrogoderma granarium Everts andRhizopertha dominica Fabricius was biologically evaluated by rat growth and nitrogen balance studies. Feeding of diet containing insect infested sorghum grains (50 and 75%) resulted in marked decrease in food intake, protein intake, gain in body weight, food efficiency ratio, protein efficiency ratio, nitrogen consumption, nitrogen absorption, biological value, net protein utilization, dry matter digestibility, net protein retention and protein retention efficiency. These parameters showed negative association with insect infestation levels. However, 25% level of grain infestation did not affect these parameters significantly.  相似文献   

19.
Native to the neotropics, the avocado seed moth Stenoma catenifer Walsingham (Lepidoptera: Elachistidae) is a specialist pest of the family Lauraceae and considered one of the most important pests of avocados worldwide. However, little is known regarding its spatial distribution within a single tree. Therefore, we designed a study to evaluate the effects of canopy height and aspect (i.e., side of the tree) on fruit infestation by S. catenifer larvae in avocados. The study was conducted in three commercial organic avocado orchards located in São Paulo, Brazil. At each orchard, 40 fruit from 30 random trees were sampled weekly from October 2017 through February 2018, evaluating the number of fruits infested by S. catenifer larvae at three tree heights (bottom, middle, and top). In addition, fruits on the ground were also sampled. We also evaluated the effect of the side of the tree where the fruits were collected, i.e., whether they were on the side facing the east (sunrise) or the west (sunset). Within the avocado canopy, the level of fruit infestation by S. catenifer larvae was significantly higher at the top of the trees than in the middle and bottom. Fruit on the ground had lower levels of infestation than those on the tree canopy. The level of fruit infestation was also higher on the side of avocado trees facing the east (sunrise). Understanding the within-tree distribution of S. catenifer will help to better target monitoring and control activities against this pest in avocados.  相似文献   

20.
Effects of sowing date, fungicide seed treatments, and the head smut fungus Ustilago bullata Berk, on establishment, herbage, and seed production of prairie grass cv. Grasslands Matua ( Bromus willdenowii Kunth ) were measured in autumn- and spring-sown field trials in New Zealand.
Autumn seedling establishment from thiram-treated seed relative to untreated seed was increased by 27% from the earliest sowing (early March), and by 65% from the latest sowing 8 weeks later. Infestation of seed with ustilospores of U. bullata reduced seedling establishment at all but the latest autumn sowing. Fungicide seed treatments had little effect on spring seedling establishment, but V. bullata infestation of seed reduced establishment compared with healthy seed, particularly after late sowings (early November).
Herbage production was greater from early than from late sowings in both autumn and spring, and was less in plants grown from U. bullata infested seed than in plants from healthy seed. Enhanced autumn establishment from thiram-treated seed led to improved herbage production when plants were young, but this effect disappeared about 18 weeks after late autumn sowing. Overall herbage production from spring sowing was more than twice that from autumn sowing.
A 6-week delay in autumn sowing led to a 58% reduction in seed production the following summer.
Early autumn and spring sowings, together with adequate control of seedling diseases, are likely to give optimum herbage and seed production from prairie grass.  相似文献   

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