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131.
High concentration of reduced iron (Fe2+) in waterlogged acid soils is a constraint for growing wheat in high rainfall (waterlogged-prone) areas of Western Australia. Growing crop genotypes tolerant to high Fe2+ concentrations may be desirable in such situations, but there is no knowledge about the extent of variability in Fe2+ tolerance in the wheat germplasm. A bioassay for tolerance to high concentrations of iron in wheat was developed and optimised using Siete Cerros (Fe-tolerant) and BH1146 (Fe-intolerant) as control genotypes and a range of FeSO4 concentrations (36, 313, 625, 1250, 1875, 2500 and 3125 μM Fe2+) in nutrient solution in a controlled-temperature environment. Increasing external concentration of iron decreased both shoot and root dry weight, increased shoot iron concentration and intensified the development of toxicity symptoms to a greater degree in intolerant BH1146 as compared to tolerant Siete Cerros. Increased iron supply negatively affected uptake of Ca (r = −0.41) and Mg (r = −0.40). The tolerant genotype Siete Cerros showed an improved avoidance/exclusion of high external concentration of Fe2+ compared with intolerant BH1146. The genotypic discrimination based on relative root dry weight and the development of toxicity symptoms was most pronounced at 625 μM Fe2+. This concentration was chosen for screening of 20 bread wheat and one durum genotype chosen from a preliminary screening of 94 Australian wheat genotypes. A relatively narrow but significant variation (22–38%) in terms of relative root dry weight under Fe2+ toxicity was observed among Australian advanced breeding lines and varieties. The presence of genotypic variation for Fe2+ tolerance across and within the Australian breeding programs could be exploited in a deliberate selection process to enhance Fe2+ tolerance in wheat. Durum wheat (Arrivato) and several Australian wheat varieties and advanced lines in this study were as tolerant to Fe2+ toxicity as Siete Cerros, a variety representing common parentage of iron-tolerant genotypes.  相似文献   
132.
Background: Thiamine (VitB1) is a vitamin with various important physiological functions and postulated therapeutic effects. Its use as an analgesic in neuropathic pain has been undergoing in clinical settings. However, there has been little experimental investigation on this effect. In this study, anti-nociceptive and anti-inflammatory effects of thiamine were investigated in mice. Methods: Three doses of thiamine (50, 100 and 125 mg/kg) were used by intraperitoneal injection in this study. Acute and chronic anti-nociceptive effects were examined using hot plate test alone and after sciatic nerve ligation, respectively. Imipramine (40 mg/kg) was used as positive control. Anti-inflammatory effects of thiamine on acute and chronic inflammation were assessed using xylene-induced edema in ears and granuloma caused by compressed cotton implantation, respectively. Sodium diclofenac (15 mg/kg) was used as positive control. Open field test was performed to differentiate the mice responses in the acute anti-nociceptive tests. Results: All three doses of thiamine showed significant analgesic effects in non-ligated mice and also in neuropathic pain in ligated animals. Increasing the dose of thiamine correlated with a more pronounced and sustained effect. Acute anti-inflammatory investigation showed that thiamine injected 30 or 60 minutes before xylene application reduced the weight of edematic ears. However, the effect of thiamine was less pronounced than diclofenac. Furthermore, when injected once daily for 7 days, all doses of thiamine significantly reduced the weight of the cotton disks, showing suppression of granuloma formation. Conclusion: Taken together, it has been shown that thiamine possesses remarkable analgesic activities and also has significant anti-inflammatory effects, confirming its clinical use in controlling pain and less in inflammation.  相似文献   
133.
In this research work, aramid and semi-carbon fibers (SCFs) were hybridized in the form of interlayer or layer by layer into epoxy matrix by hand lay-up method. Afterward, the effect of hybridization on the thermal and mechanical properties of epoxy composites was characterized by thermal analysis; horizontal burning; tensile and bending tests. Based on the results of the mechanical tests, increasing SCFs to aramid fibers ratio decreased tensile strength, elastic and flexural modulus. But with increasing this ratio to 53 % failure strain reduced, whereas in the ratios of more than 53 %, the failure strain enhanced. The results of thermal analysis curves indicated that there are three stage mass loss at the temperature ranges of 100-220, 270-470 and 500-620 °C. It was also found that with increasing the SCFs to aramid fibers ratio decreased the third-stage of the mass loss. The results of horizontal burning showed that increasing the SCFs to aramid fibers ratio decreased the rate of burning.  相似文献   
134.
The heterogeneity of CD4+ T cells has been investigated since the late 1970s, when their Th1 and Th2 subsets were coined. Later studies on the cutaneous form of the Leishmaniasis were focused on the experimental models of Leishmania major infection using the susceptible BALB/c and the resistant C57BL/6 mice. At the early 21st century, the Treg subpopulation was introduced and its role in concomitant immunity, responsible for lifelong resistance of the host to the reinfection was proposed. Subsequent studies, mainly focused on the visceral form of the infection pointed to the role of IL-17, produced by Th17 subset of CD4+ T cells that along the neutrophils were shown to have important yet equivocal functions in protection against or exacerbation of the infection. Altogether, the current knowledge indicates that the above four subsets could orchestrate the immune, the regulatory and the inflammatory responses of the host against different forms of leishmaniases. Key Words: Immunity, Leishmaniasis, T-Lymphocytes  相似文献   
135.

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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136.
137.
Ovulation rate and litter size are important reproduction traits in sheep and are of high economic value. Reproduction traits typically have low to medium heritabilities and do not exhibit a noticeable response to phenotypic selection. Therefore, inclusion of genetic information of the genes associated with reproductive ability could efficiently enhance the selection response. The most important major genes affecting prolificacy and their genetic diversities in different sheep breeds were reviewed. Different causative mutations with major effects on reproductive traits including ovulation rate and litter size have been found in various sheep breeds around the world. A general overview of the studies on main prolificacy genes showed that some alleles may express different phenotypic effects in different breeds, and thus, further studies on epistatic effects are necessary for more understanding of genetic control of reproductivity in sheep. Regarding the polygenic control of fertility traits, application of new high‐throughput technologies to find new variants is essential for future studies. Moreover, genomewide association studies and genomic best linear unbiased predictions of breeding values are likely to be effective tools for genetic improvement of sheep reproductive performance traits.  相似文献   
138.
Regarding the importance of the presence of intestinal lactobacilli and their population in infants, four different treatments were evaluated for Lactobacillus isolation efficiency via reduction in the growth of other groups of bacteria capable of growing on de-Man Rogosa Sharpe (MRS) medium from fecal samples of 11 Iranian infants. MRS-Vancomycin (1 mg L(-l)) was used as a base medium and application of lactic acid and aerobic incubation of inoculated plates were performed as selective factors. Each fecal sample was cultivated as duplicate on to the base medium with or without lactic acid to reduce the pH to 5.4 +/- 0.2. Half of the plates were incubated aerobically and the rest of them incubated under 10% CO2 concentration. Total count and Lactobacillus count of all samples were recorded according to the age differences of infants. The counts of false positive colonies were recorded with respect to their cell morphology and gram reaction in all treatments. Anaerobic incubation of lactic acid modified MRS-Vancomycin gave the most Lactobacillus percentage coverage, about 93% among the Lactobacillus positive samples. Using this treatment, the median Lactobacillus count yielded 8.29 log10 cfu g(-1) in the younger and 5.70 log10 cfu g(-1) in the elder group. It could be concluded that lactic acid might be a proper pH reducing agent when enumeration of lactobacilli from fecal samples is of interest.  相似文献   
139.
A qualitative and quantitative analysis of rutin from leaves, fruits and flowers of Capparis spinosa growing wild in Khuzestan was achieved. After soxhelet extraction of fats in diethyl ether, rutin was extracted by maceration using 50% EtOH. The ethanol extracts of these parts were separated by preparative TLC on silica gel precoated plate with a mixture of butanol: acetic acid (4:1, by volume) as the developing solvent. The spots were visualized under ultraviolet light (254 nm). Rutin was qualified by comparison of its R(f) value with that of standard. UV/Vis spectrum of separated rutin was also compared with those of standards and showed characteristic wavelengths at 260 and 360 nm. Purified rutin was quantified by UV/Vis spectrophotometric determination at 360 nm. The calibration curve was linear in the range of 0.156-2.5 microg mL(-1) with detection limit of 0.0731 microg mL(-1). The purity of extracted rutin from leave, flower and fruit determined by high performance liquid chromatography were 90.41, 87.25 and 64.56%, respectively. The amounts of rutin in leaves, fruits and flowers were 61.09, 6.03 and 43.72 mg per 100 g of dried powder, respectively. By analyzing the spiked samples of leave, flower and fruit the recovery of the UV/Vis method was in the range of 102-107.6%.  相似文献   
140.
The effects of moisture content (8%, 10%and 12%), variety (Tarom and Fajr) and parboiling on milling quality of rice as a function of milling recovery (MR), head rice yield (HRY), degree of milling (DOM) and whiteness were investigated. The parboiled grains was prepared with three soaking temperatures of 25 oC, 50 oC and 75 oC and three steaming times of 10, 15 and 20 min. As a result of parboiling, the increasing rates of MR and HRY values were 7.8%and 14.3%for Tarom and 9.8%and 10.0%for Fajr, respectively, and the decreasing rates for DOM and whiteness were 6.6%and 10.8%for Tarom and 6.8% and 10.5% for Fajr, respectively. Moreover, decreasing moisture content to 8%maximized MR (75.8% for Tarom and 74.3% for Fajr) and HRY (65.8% for Tarom and 57.0% for Fajr) while increasing that to 12%revealed maximum values of DOM (6.1%for Tarom and 6.2%for Fajr) and whiteness (24.8%for Tarom and 28.2%for Fajr).  相似文献   
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