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171.
Tropical Animal Health and Production - The purpose of this model-based study was to identify behavioral and environmental prevention factors for brucellosis and to determine the causal linkage...  相似文献   
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Tropical Animal Health and Production - In tropical countries, one of the major threats for diary animal production is climate change. Ambient management interventions are beneficial and are the...  相似文献   
174.

The effects of screened lactic acid bacteria strains were evaluated on growth performance, humoral immunity, and IGF-1 gene expression in broiler chickens. The three dietary groups of negative control fed basal diet, the native LAB probiotic group (NP), and PrimaLac commercial LAB probiotic (PC) were studied. The results revealed that NP and PC diets significantly improved feed conversion ratio and increased body weight, as well as relative weight of carcass compared with group fed NC diet (P?<?0.05). Lymphocyte level was significantly increased in birds fed NP and PC (P?<?0.01), while serum triglycerides and total cholesterol levels were significantly decreased compared with the NC (P?<?0.05). Significant increases were observed in antibody titers against Newcastle disease virus of vaccinated birds (P?<?0.03), and morphological analysis of ileum revealed significant increases (P?<?0.05) in the villus height and villus height/crypt depth in birds fed NP and PC compared with the NC. The dietary significantly increased Lactobacillus spp. (P?<?0.05), while Escherichia coli (P?<?0.04) populations were significantly decreased, and also, the expression of IGF-1 gene in liver tissue of broilers fed NP and PC was significantly increased compared with the NC (P?<?0.05). These results indicated that the identified native LAB strains can be used commercially as a low-cost probiotic in poultry industry of Iran.

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BACKGROUND: Congenital Adrenal Hyperplasia (CAH, the inherited inability to synthesize cortisol) is one of the most common (1 in 10000 to 1 in 15000) autosomal recessive disorders. More than 95% of cases of CAH are caused by 21-hydroxylase deficiency (21-OHD). Females with severe, classic 21-OHD are exposed to excess androgens prenatally and are born with virilized external genitalia. Most patients cannot synthesize sufficient aldosterone to maintain sodium balance and may develop potentially fatal salt wasting crisis if not treated. METHODS: We applied allele specific PCR to detect the eight common mutations in the CYP21 gene in patients. Fifty unrelated patients with symptoms of classical CAH were studied. RESULTS AND CONCLUSION: Seventy percent of our subjects had these mutations. The most frequent mutations were found to be I2G and del-8 bp (28% and 13%, respectively). The frequencies of other alleles were as following: I172N, 9%; V281L, 3%; exon 6 cluster (I236N, V237E and M239K), 4%; Q318X, 9%; R356W, 5%; and P30L, 0%. The frequency of mutations did not differ substantially from other ethnics, however, a higher rate of del-8 bp (13%) was found in our population. The aim of this study was to detect common mutations for setting up a molecular method for prenatal diagnosis.  相似文献   
177.
Metasystox-R is a systemic soluble liquid insecticide for the control of aphids on brassica vegetable crops, cotton and lupins and it is possible enter to the marine environment and may be have a hazard effects for the marine organisms and nitrification processes. Effect of Metasystox-R on ammonia oxidizing activity by marine Nitrosomonas sp. was investigated by determining nitrification inhibitor assay in the cell suspension. Results showed that 8 microg mL(-1) of Metasystox-R with PI50 = 4.48 significantly inhibited nitrite production by marine Nitrosomonas sp. These results suggested marine Nitrosomonas sp. may be one of the target bacteria which was inhibitor and decreasing nitrification in the marine environment.  相似文献   
178.
The present study was aimed to identify the association of overweight and obesity with gastroesophageal reflux disease (GERD). This age- and sex-matched case-control study was carried out in a sample of subjects referred to the specialized clinic of Tabriz University of Medical Sciences from November 2006 to March 2007. Data were collected using a demographic questionnaire and a checklist to determine reflux symptoms. Weight and height were measured and Body Mass Index (BMI) was calculated. Logistic regression was used to examine the association between overweight, obesity and reflux symptoms. The study population included 106 cases (with reflux symptoms) and 111 controls with a mean age of 35.2 +/- 12.9 years. The mean BMI was 2.4 units greater in cases than controls (p = 0.0001). In unadjusted model, overweight (OR = 3.41, CI: 1.8-6.44) and obesity (OR = 2.84, CI: 1.38-5.82) were significantly associated with GERD. Results of multivariate logistic regression revealed significant association between overweight and GERD after adjusting for confounders (OR = 2.87, CI: 1.49-5.53). Given the increasing prevalence of patients with both overweight/obesity and GERD, Serious dietary intervention studies for weight loss as a therapeutic strategy should be carried out in GERD patients complicated with obesity.  相似文献   
179.
The effect of groundwater velocity onbioremediation of gasoline contaminated sandy soil hasbeen investigated using a pilot scale sand tank model.The effect of hydrogen peroxide and contaminantconcentration are also included. A factorialexperiment has been conducted to study three factors,groundwater velocity, inlet BTX concentration andhydrogen peroxide dose. Observed concentration datacollected from the sand tank model have been used forestimating the transport parameters. Three differentbiodegrdation kinetics, namely first-order/zero-order,Monod and Michaelis Menten (a modification of Monodkinetics considering no microbial growth) kineticshave been used to model the biodegration. The datahave been found to fit all three models withacceptable coefficient of regression. Groundwatervelocity has been found to be the most significantfactor governing the biodegradation rate constants(determined from the first-order rate constant) of BTXcompounds. Hydrogen peroxide dose and BTX concentration have also been found to be significant factors.  相似文献   
180.
The effects of super absorbent polymers (SAPs) on growth characteristics and seedlings survival of Artemisia sieberi (under two soil textures, three irrigation levels and seven hydrogel compositions with three replications) were investigated. The studied traits were shoot height, shoot dry weight, root dry weight, ratio of root/shoot, root length, root perimeter, root area and root volume. SAPs successfully enhanced growth capability of A. sieberi in two soil textures compared to the controls. Ideally, 5 g kg?1 Aquasorb? (SNF Company, France) with 100% irrigation and 10 g kg?1 Stockosorb® (Evonik Corporation, Germany) with 75% irrigation in a sandy loam texture and 10 g kg?1 Boloorab A? (Boloorab Company, Iran) with 75% irrigation in a loamy texture significantly affected all traits, resulting in 100% survival for A. sieberi seedlings. Aquasorb? and Stockosorb® showed the best results in the sandy loam texture and preferable outputs were obtained by Boloorab A? application in the loamy texture. In other words, because of the basic differentiation among soils in terms of mineralogy, temperature and moisture content, different SAPs should be applied. Production of dense root network and root aggregation stimulated by SAPs increased root contact with moisture. Therefore, improving the growth and survival of the plants is accessible using SAPs under water stress condition.  相似文献   
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