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101.
Ghanbarpour Reza Sami Masoud Salehi Mahmood Ouromiei Mahla 《Tropical animal health and production》2011,43(1):153-157
The purposes of this study were to determine the phylogenetic background and the virulence gene profiles of Escherichia coli isolates from colisepticemic and feces of healthy (AFEC) broiler chickens. In this study, 253 E. coli isolates including 141 avian pathogenic E. coli (APEC) and 112 AFEC isolates were examined by PCR. In general, 253 E. coli isolates distributed among group A (51.8%), B1 (15.8%), B2 (8.7%), and D (23.7%). Ten (8.9%) AFEC isolates segregated in
to B1 phylo-group and 102 (91.1%) isolates fell into six different phylogenetic subgroups. Distribution of colisepticemic
and fecal isolates differed significantly in their assignments to A and B1 phylo-groups. The three most prevalent virulence
genes were crl, fimH, and aer in isolates between both groups. The four genetic markers aer, papC, afa, and sfa were detected significantly more often among colisepticemic isolates than in fecal isolates from healthy broilers. The presence
of stx
2
gene in fecal isolates were significantly differs among the colisepticemic isolates. F17 fimbrial family encoding gene and
eae gene were detected in APEC and AFEC isolates, respectively. The colisepticemic and fecal isolates possessed the virulence
genes were detected in all of the four phylogenetic groups. Several combination patterns of the virulence genes were detected
in APEC and AFEC isolates. In colisepticemic isolates the combination of aer, crl, and fimH genes was the most prevalent pattern. None of the examined isolates harbored the cdt, cnf1, ipaH, and stx
1
virulence gene sequences. 相似文献
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103.
To evaluate the genetic relationships among wild and cultivated Pistacia species grown in Iran and the analysis of genetic variation among Iranian pistachio genotypes, two DNA libraries enriched for dinucleotide (AG)n and trinucleotide (ATG)n microsatellite motifs were developed from Pistacia khinjuk genome. Following screening of clones by colony PCR technique, 44 clones were sequenced and 27 pairs of primers designed from flanking regions of the repeats. The examination of primer pairs, designed from P. khinjuk sequences, showed successful cross-species amplification within the genus Pistacia. A dendrogram constructed on the basis of the Minimum Evolution clustering algorithm revealed that Pistacia vera has closer relationships with P. khinjuk, than with Pistacia integerrima, Pistacia palaestina, Pistacia atlantica and Pistacia mutica. The dendrogram further distinguished the wild Sarakhs pistachio from the rest of P. vera genotypes suggesting that the domesticated genotypes of P. vera are evolved from P. vera var. Sarakhs and then this wild genotype likely develops to other local pistachios. Hence, it seems that the wild Sarakhs pistachio plays an important role in evolutionary trend of the edible pistachios in Iran. The results indicated that microsatellites developed in P. khinjuk are distributed in the genome of indigenous pistachio species including P. vera genotypes and therefore they will be useful in characterization of Iranian pistachio genotypes. 相似文献
104.
Masoud Hashemi Ali Farsad Amir Sadeghpour Sarah A. Weis Stephen J. Herbert 《植物养料与土壤学杂志》2013,176(1):69-75
Planting cover crops after corn‐silage harvest could have a critical role in the recovery of residual N and N from fall‐applied manure, which would otherwise be lost to the environment. Experiments were conducted at the University of Massachusetts Research Farm during the 2004–2006 growing seasons. Treatments consisted of oat and winter rye cover crops, and no cover crop, and four cover‐crop dates of planting. The earliest planting dates of oat and winter rye produced the maximum biomass yield and resulted in the highest nitrate accumulation in both cover‐crop species. The average nitrate accumulation for the 3 years in winter rye and oat at the earliest time of planting was 60 and 48 kg ha–1, respectively. In 2004 where the residual N level was high, winter rye accumulated 119 kg nitrate ha–1. While initially soil N levels were relatively high in early September they were almost zero at all sampling depths in all plots with and without cover crops later in the fall before the ground was frozen. However, in plots with cover crops, nitrate was accumulated in the cover‐crop tissue, whereas in plots with no cover crop the nitrate was lost to the environment mainly through leaching. The seeding date of cover crops influenced the contribution of N available to the subsequent crop. Corn plants with no added fertilizer, yielded 41% and 34% more silage when planted after oat and rye, respectively, compared with the no–cover crop treatment. Corn‐silage yield decreased linearly when planting of cover crops was delayed from early September to early or mid‐October. Corn‐ear yield was influenced more than silage by the species of cover crop and planting date. Similar to corn silage, ear yield was higher when corn was planted after oat. This could be attributed in part to the winter‐kill of oat, giving it more time to decompose in the soil and subsequent greater release of N, while the rapidly increasing C : N ratio of rye can lessen availability to corn plants. Early plantings of cover crops increased corn‐ear yield up to 59% compared with corn‐ear yield planted after no cover crop. 相似文献
105.
The aim of this work was to determine metal accumulation by plants growing on three molybdenum-mine zones and their tolerance strategies. The plants from tailing, extracting and non-contaminated zones were sampled with their corresponding soils. The results show that molybdenum (Mo) and copper (Cu) were at toxic levels in soils and their levels varied in 44 collected species from 21 families. Ajuga chamaecistus and Cramb orientalis L. excluded Mo and Cu, respectively. Achilla tenuifollia as Mo-hyperaccumulator with total Mo (1979 mg kg?1) and then Erodium ciconium with 1308 mg kg?1 Mo and Conyza Canadensis with 618 mg kg?1 Cu were moderate metal accumulators. They stored considerable levels of metals in their leaves vacuoles and elevated the levels of phytochelatins, cysteine and glutathione and induced antioxidant enzymes. In conclusion, this study indicated that some collected plants excluded metals. In metal-accumulators, antioxidant enzymes, phytochelatins and sequestration of excess metals were involved in their tolerance mechanism. 相似文献
106.
Fatemeh Zamani Masoud Latifi Mohammad Amani-Tehran Mohammad Ali Shokrgozar 《Fibers and Polymers》2013,14(5):698-702
Electrospinning has been recognized as an efficient technique for the fabrication of neural tissue engineering scaffolds. Many approaches have been developed on material optimization, electrospinning techniques, and physical properties of scaffolds to produce a suitable scaffold for tissue engineering aspects. In this study, structural properties of scaffolds were promoted by controlling the speed of fiber collection without any post-processing. PLGA scaffolds, in two significantly different solution concentrations, were fabricated by the electrospinning process to produce scaffolds with the optimum nerve cell growth in a desired direction. The minimum, intermediate and maximum rate of fiber collection (0.4, 2.4, 4.8 m/s) formed Random, Aligned and Drown-aligned fibers, with various porosities and hydrophilicities. The scaffolds were characterized by fiber diameter, porosity, water contact angle and morphology. Human nerve cells were cultured on fiber substrates for seven days to study the effects of different scaffold structures on cell morphology and proliferation, simultaneously. The results of MTT assay, the morphology of cells and scaffold characterization recommend that the best structure to promote cell direction, morphology and proliferation is accessible in an optimized hydrophilicity and porosity of scaffolds, which was obtained at the collector linear speed of 2.4 m/s. 相似文献
107.
Karimi Vahid Mohammadi Peyman Ghalyanchilangeroudi Arash Ghafouri Seyed Ali Hashemzadeh Masoud Farahani Reza Khaltabadi Maghsouldoo Hussein Isakakroudi Nima 《Tropical animal health and production》2019,51(3):629-635
Tropical Animal Health and Production - Infectious bronchitis virus (IBV) is a highly infectious pathogen, which affects the respiratory tract, reproductive system, and kidney of chickens. Many... 相似文献
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109.
Abdolmohammad Abedian Kenari Joe M. Regenstein Masoud Rezaei Reza Tahergorabi Rajab Mohammad Nazari 《Journal Of Aquatic Food Product Technology》2013,22(3):245-265
The amino acids (AA) and fatty acids (FA) of Beluga (Huso huso) flesh at different ages were investigated as a source of AA and FA for human consumption. The analysis of Huso huso lipids (chloroform extracted) showed significant differences (p < .05) for specific FA with age. At all ages, the major saturated FA in Huso huso fillets was palmitic acid and the major unsaturated FA were oleic and docosahexanoic acid (DHA). Protein analysis indicated that the Huso huso muscle is well balanced with good levels of essential AA and appears to be a source of high quality protein (tryptophan was not measured) with methionine/cysteine as the first limiting AA. The major AA were glutamic acid, aspartic acid, and lysine. The results obtained from the present study show that Huso huso is an excellent protein and fat source when compared with other sturgeons. 相似文献
110.
Leila Beigom Hejazian Banafshe Esmaeilzade Fatima Moghanni Ghoroghi Fatemeh Moradi Marzieh Beigom Hejazian Anahita Aslani Mehrdad Bakhtiari Masoud Soleimani Maliheh Nobakht 《Iranian Biomedical Journal》2012,16(4):193-201