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91.
ABSTRACT

Application of alkaline biochar has been proposed as an alternative to lime for remediation of acidic soils. However, questions remain as to how the reactions and fate of metals in acidic soils can be affected by biochar amendment. To find out how biochar addition might affect sorption-desorption behavior of zinc (Zn) in acidic soils, a soil with an initial pH value of 4.67 was treated with different levels [0 (control), 1%, 3%, and 6%] of biochar produced from pyrolysis of sugarcane bagasse at 600°C and incubated for 30 days under 80% of water holding capacity. At the end of the incubation period, important soil chemical properties were measured and batch isotherm experiments were performed to determine soil Zn sorption-desorption parameters. The results showed that the biochar-amended soils had higher pH values (up to 2.5 pH units), electrical conductivity (up to 2.66 times), and cation exchange capacities (up to 42%) relative to the un-amended acidic soil. Biochar addition also led to significant enhancements in soil exchangeable calcium, magnesium, sodium, and potassium cations. Both sorption and desorption isotherm experiments revealed the significantly higher capacity of the biochar-amended soils to retain Zn than that of the control. Moreover, the biochar-amended soils exhibited a higher affinity for Zn sorption than did the un-amended acidic one. It can be concluded that biochar derived from sugarcane bagasse could serve as a good amendment material to reclaim acidic soils and to reduce Zn mobility and toxicity in acidic metal-contaminated soils.  相似文献   
92.
Eurasian Soil Science - Arid and semiarid soils of southern Iran may fix a large content of applied potassium (K), but the fixed K may be gradually supplied to plants. Sixteen representative soils...  相似文献   
93.
Background:This study investigated the antinociceptive effect of cumin and its biosynthesized AuNPs. Methods:Cumin extract (E) and cumin-AuNPs (GN) were prepared and administered intraperitoneally at the concentrations of 200, 500, and 1000 mg/ml to 27 male rats. UV–Vis spectroscopy and AFM were applied for AuNPs synthesis confirmation. The nociceptive behavior was assessed, and IL-6 serum levels were measured. Results:Cumin-AuNPs showed a peak absorption of 515 nm, and a size of about 40 nm. Three different concentrations of extract had no significant effect on acute and chronic nociceptive behavior. GN + E200 (46.00 ± 10.59) showed a significant acute anti-nociceptive effect compared to the control (98.66 ± 4.91; p = 0.029) and SS300 (98.33 ± 20.30; p = 0.029) groups. Also, GN + E500 (42.00 ± 11.84) significantly reduced acute nociceptive behavior compared to the control (98.66 ± 4.91; p = 0.019), SS300 (98.33 ± 20.30; p = 0.020), and GN + E1000 (91.00 ± 26.00; p = 0.040) groups. IL-6 serum levels reduced significantly in GN + E500 (24.65 ± 10.38; p = 0.002) and SS300 (33.08 ± 1.68; p = 0.039) compared to the controls (46.24 ± 3.02). Chronic nociceptive behavior was significantly lower in the SS300 (255.33 ± 26.30) compared to E200 (477.00 ± 47.29; p = 0.021), E500 (496.25 ± 46.29; p = 0.013), and GN + E500 (437.00 ± 118.03; p = 0.032) groups. Conclusion: Our findings suggest the potential effects of cumin-AuNPs on formalin-induced nociceptive behavior, which is independent of IL-6serum levels.Key Words: Interleukin-6, Pain, Cuminum cyminum L., Gold Nanoparticles, Green Synthesis  相似文献   
94.
Meat inspection records in an abattoir located in Shiraz, a city in southwest Iran and the capital of Fars province, during a 5-year period from 20 March 1999 to 19 March 2004 were used to determine the prevalence of hydatidosis in sheep, cattle, and goats in the region. A total of 844,039 animals (cattle 131,716; sheep 577,090; goats 135,233) slaughtered in the 5-year period and overall 34,856 (4.1%) livers and 123,402 (14.62%) lungs were condemned. Hydatidosis was responsible for 28.7 and 15.4% of total livers and lungs condemnations, respectively. The overall trend for all livestock and in both organs was a significant downward one. The annual prevalence of liver condemnations due to hydatidosis was decreased from 2.1, 1.8, and 1.0% in 1999-2000 to 0.62, 0.33, and 0.20% in 2003-2004 for cattle, sheep, and goats, respectively. The corresponding features for lung condemnation due to hydatidosis were relatively higher than liver, declining from 3.0, 4.6, and 4.4% in 1999-2000 to 1.3, 1.5, and 0.56% in 2003-2004, for cattle, sheep, and goats, respectively. Greater awareness among farmers, destruction of organs containing hydatid cysts, prevention of access of dogs to raw offals and implementation of national rabies control program could be responsible factors. Data showed significant seasonal pattern for hydatidosis in all species. Liver condemnations due to hydatidosis were higher in the spring and summer for sheep, whereas lung condemnations were higher in summer for both sheep and goats. Liver and lung condemnations in cattle were higher in winter. This could be attributed to various factors such as sources of slaughtered animals, changes in management practice and ecological factors. The overall trend was relatively the same when annual condemnations were adjusted for the effect of seasonal variation. The present survey provides baseline data for the future monitoring of this potentially important parasitic disease in the region.  相似文献   
95.
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   
96.

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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97.
98.
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   
99.
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   
100.
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   
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