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41.
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   
42.
Macroelements in leaves and fruits, sugar of fruits, and yield of ‘Khatooni’ melon were compared with melons grafted onto rootstocks cvs. ‘Ace’, ‘Shintozwa’, and ‘ShintoHongto’, and trained into three methods: T1) no pinching and fruit thinning; T2) pinched to produce two lateral branches; and T3) pinched to two branches and all flowers and lateral branches from lower nodes thinned. Concentrations of nitrogen (N), phosphorus (P), and potassium (K) increased in leaves onto ‘Shintozwa’, whereas opposite trends observed for magnesium (Mg) and calcium (Ca). N, P, and K in leaves were significantly higher by 21.5%, 17.2%, and 18.6%, respectively in grafted. N, P and K in fruits onto ‘Ace’ and ‘Shintozwa’ were higher, with exception of Ca and Mg in non-grafted. ‘Ace’ and ‘Shintozwa’ resulted in significant increase in Khatooni yield. T3 showed the highest yield. Soluble solids concentration (SSC) was higher in non-grafted fruits. T2 produced fruits with the highest SSC.  相似文献   
43.
Background: Friedreich ataxia (FRDA) is an autosomal recessive disorder caused by guanine-adenine-adenine (GAA) triplet expansions in the FXN gene. Its product, frataxin, which severely reduces in FRDA patients, leads to oxidative damage in mitochondria. The purpose of this study was to evaluate the triple nucleotide repeated expansions in Iranian FRDA patients and to elucidate distinguishable FRDA clinical differences in these patients. Methods: A number of 22 Iranian patients (8 females and 14 males) from 16 unrelated families were studied. DNA was extracted from the peripheral blood of patients. The frequency and length of (GAA)n repeats in intron 1 of the FXN gene were analyzed using long-range PCR. In this study, the clinical criteria of FRDA in our patients and the variability in their clinical signs were also demonstrated. Results: An inverse relationship was observed between GAA repeat size and the age of onset. Although some distinguishable clinical features (such as limb ataxia and lower limb areflexia) were found in our patients, 90-95% of them had extensor plantar response and dysarthria. The results showed only one positive diabetes patient and also different effects on eye movement abnormality among our patients. Conclusion: The onset age of symptoms showed a significant inverse correlation with allele size in our patients (P>0.05). Based on comparisons of the clinical data of all patients, clinical presentation of FRDA in Iranian patients did not differ significantly from other FRDA patients previously reported. Key Words: Friedreich ataxia (FRDA), Frataxin, Mitochondria  相似文献   
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In most rainfed production areas where wheat fallow is common, crop yield could be improved by changing to more diverse crop rotations. It seems necessary to identify crop cultivars suitable for such diversification. This study was aimed at determining the responses of two common bean cultivars with different growth habits (Sayyad as an indeterminate and D81083 as a determinate cultivar) to drought stress. The study was conducted in a greenhouse during the 2008 growing season. A factorial experiment in a randomized complete block design with four replications and four water levels [100, 75, 50 and 25% of field capacity (FC) by weight] was used. The results showed that plant height, number of leaves, leaf area, number of pods, pod dry matter (DM) and total plant DM weights of both cultivars were significantly reduced under drought stress. Furthermore, at 50 and 25% FC, all plant pods of both cultivars were aborted. The common bean cultivar with a determinate growth habit appeared to have potential as a dryland rotation crop for farming in arid regions. Further field research might shed more light on the sensitivity of bean cultivars to drought stress with the aim of crop diversification for dryland areas, where adequate moisture supply is a limiting factor for crop production.  相似文献   
46.
The aim of this study was to compare the quality characteristics and mineral content of the fiber from male and female cashmere goats raised under different management systems. Male and female Raeini cashmere goats (<1.5 years of age, n = 48) were selected from flocks raised at a government breeding station or raised commercially under either rural or nomadic conditions. The staple length, cashmere fiber diameter, coefficient of variation for fiber diameter, percentage of cashmere in a fleece, percentage of guard hair in a fleece and cashmere tenacity averaged 4.6 ±0.1 cm, 18.0 ±0.1 m, 20.9 ± 0.4%, 66.1 ± 1.5%, 33.8 ± 1.5% and 1.8 ± 0.2 gf/tex, respectively. The sulfur, copper and zinc content of the cashmere averaged 2.8 ± 0.1%, 0.00065 ± 0.00002% and 0.01276 ± 0.00025%, respectively. Rearing method significantly affected staple length, coefficient of variation of fiber diameter, cashmere tenacity and copper content. Males had a higher coefficient of variation of fiber diameter and cashmere tenacity than females (P < 0.05).  相似文献   
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48.
Diazinon (DZN) as an organophosphate pesticide may cause oxidative stress in different tissues. Antioxidants increase tissue protection from oxidative stress. The aim of the present study was to investigate prophylactic and therapeutic effects of vitamin C against oxidative stress caused by DZN in various tissues of male Wistar rats. Thirty rats were divided into five groups: control group received corn oil as DZN solvent, DZN group received 100 mg/kg of DZN, C group received 200 mg/kg of vitamin C, C‐DZN and DZN‐C groups received vitamin C before and after DZN injection. Plasma and various tissues were prepared and evaluated for measurement of the biochemical parameters and oxidative stress biomarkers. Results showed that acute administration of DZN significantly increased superoxide dismutase and glutathione‐S‐transferase activities and malondialdehyde level in all tissues, catalase (CAT) activity in liver, kidney and heart and some plasma biochemical indices, while it decreased cholinesterase and lactate dehydrogenase activities and glutathione content in all tissues. CAT activity in erythrocytes, brain and spleen was decreased in DZN‐exposed rats compared with the control group. Administration of vitamins C in both prophylactic and therapeutic groups ameliorated in these parameters, although all these tests in tissues did not return to the normal level. These data suggest that oxidative stress is an essential mechanism involved in DZN‐induced adversity effect, as evidenced by the altered activity of antioxidant enzymes, depleted GSH content and the enhanced membrane lipid peroxidation. Both the prophylactic and therapeutic treatments of rats to vitamin C have beneficial effects against oxidative stress and cholinergic hyperactivity induced by DZN in tissues especially in the brain tissue through free radical scavenging.  相似文献   
49.

Background:

A high-fat diet (HFD) promotes the oxidative stress formation, which in turn has hazardous effects on reproductive system and fertility. The present study examines the potential positive effects of a restricted high-fat diet (RHFD) and antioxidants consumption on sperm parameters and testis tissue in rats.

Methods:

Male rats (n = 48) were divided into four groups (12 in each group): control group (Cont), HFD group, RHFD, and RHFD with astaxanthin and vitamins E and C group (RHFDA). After 12 weeks, serum analysis and sperm parameters study were performed. Sections of fixed testes were stained with Hematoxilin and Eosin to study the histological changes. A one-way ANOVA was used to compare the data.

Results:

HFD fed animals presented significant increase in weight load and serum low density lipoprotein (LDL-C) levels (P < 0.05). The sperm count in RHFD was lower than three other groups (P < 0.05) and sperm motility of RHFDA group was significantly higher than HFD and RHFD groups (P < 0.05). The histological study was showed a significant increase in spermatogonium number in RHFDA compared to three other groups (P < 0.05). The number of spermatocyte I and spermatid in RHFD was significantly (P < 0.05) lower than Cont and HFD groups.

Conclusion:

HFD and obesity can affect sperm parameters and spermatogenesis and antioxidants consumption may improve their quality. Although the RHFD is a benefit way in weight loss and decrease of LDL-C of serum, but it is suggested that is not effective on sperm quality improvement.Key Words: Spermatogenesis, high-fat Diet, Restricted fat diet, Antioxidants, Astaxanthin  相似文献   
50.
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