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BACKGROUND: The purpose of this study was to evaluate the efficiency of intracytoplasmic sperm injection (ICSI) and Piezo-assisted sperm injection after pretreatment with calcium ionophore (CaI) on the mouse embryo development. METHODS: In this study, the conventional ICSI and Piezo-ICSI procedures were used. The efficacy of the methods was examined after mouse matured oocytes were fertilized with or without CaI-treated sperms. RESULTS: Piezo-ICSI demonstrated significantly more favorable results, with a fertilization rate of 64% (conventional ICSI: 42%, P<0.001) and a cleavage rate of 73% (conventional ICSI: 58%, P<0.05). When the Piezo-ICSI procedure was performed with CaI-pretreated sperms, the cleavage rate significantly increased (92% vs. 73%, P<0.05). However, the fertilization rate did not change significantly (64% vs. 56%). CONCLUSION: The Piezo-ICSI accompanies with CaI-treated sperms is more efficient than the conventional ICSI method for fertilizing and thus obtaining more mouse embryos.  相似文献   
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Genetic diversity of 54 accessions of Aegilops tauschii from five countries was assessed using sequence-tagged microsatellites (or simple sequence repeats, SSRs) and amplified fragment length polymorphisms (AFLPs). In the case of AFLP analysis, a total of 256 amplification products obtained, 234 of them were polymorphic across all the 54 accessions. A total of 224 fragments were obtained from the 24 SSR primers and 219 of fragments were polymorphic across all the genotypes screened. Based on both AFLP and SSR markers, the highest percentage of polymorphisms were obtained in Iranian and accessions of unknown origin. The highest polymorphic information content (PIC) value was observed for SSRs (0.82) while the highest marker index (MI) value was for AFLPs (8.5) reflecting the hyper-variability of the first and the distinctive nature of the second system. Principal co-ordinate analysis (PCO) revealed congruent patterns of genetic relationships for both data sets, but did not group accessions strictly according to their geographical origins. Poor correlation was found between AFLP and SSR marker loci. This low association may be due to low number of AFLP and SSR markers. These results show that molecular markers can help to organize the genetic variability and expose useful diversity for breeding purposes.  相似文献   
4.
With the aim of extending the vase life of cut rose flowers, we investigated whether the application of salicylic acid (SA), pre- and postharvest, could improve this. For this purpose, two individual trials were conducted, using a completely randomised design, with three replications. In the first trial, aqueous solutions of 0, 0.5, 1.0 and 1.5 mM SA were sprayed on roses grown in a controlled greenhouse once the flower buds had appeared, and the second stage was performed two weeks before harvest. The preharvest SA application at 1.5 mM concentration prolonged the vase life of cut roses by improving membrane stability, and decreasing the lipid peroxidation properties. In the second trial, continuous exposure to (0, 0.5, 1.0 and 1.5 mM), and pulses of (0, 5, 10 and 15 mM), SA significantly extended the vase life. Flowers treated with 1.5 (continuous exposure) and 15 mM (pulse) SA showed a significant decrease in weight loss, and antioxidant activity increased, compared to the control solution, but the flowers in the control solution indicated an increase in weight loss. The results show that pre- and postharvest SA application prolonged the vase life of cut roses through improving CAT and POD activity, and decreasing lipid peroxidation.  相似文献   
5.
In order to investigate the effect of nitrogen (N) and sulfur (S) fertilizers on yield and seed quality of three canola cultivars, a factorial based on randomized complete block experiment was conducted during 2005–2006 in Iran. Treatments included four nitrogen rates (0, 75, 150, and 225 kg N ha?1 source of urea), four sulfur rates (0, 100, 200, and 300 kg S ha?1), and three cultivars (‘Pf’, ‘Option-500’, and ‘Hyola-401’). Results indicated cultivar had a significant effect on all studied traits. ‘Option-500’ and ‘Hyola-401’ cultivars had the highest seed yield, protein content, and N:S ratio in seed. The levels of 150 and 220 kg N ha?1 resulted in the maximum protein content. Increasing N levels resulted in N content and decreased the oil content. The interaction effect between S and N levels showed the highest N content in seed was obtained with 300 kg S ha?1 and 225 kg N ha?1.  相似文献   
6.
This project was aimed to examine the NK92 cells response as the CXC chemokine responder cells in rat model of liver disorder and injuries. Hepatocytes were isolated from Sprague-dawly rats and cultured on collagen type 1. Migration of NK92 cells was assessed using a 48 well micro-chemotaxis technique. Transwell chambers were positioned faced up, blocked Medium supernatant (500 microL) obtained from hepatocytes cultures were placed into the lower compartment of each Transwell. The upper compartment was filled with either 500 microL of NK92 cells. After washing, Membrane-attached cells were fixed; stained and Membrane-attached cells were counted by light microscopy and/or by size gating (9-14 microm) with an automated counter system. Human NK92 cells were attracted to recombinant human IP-10 in a concentration and time-dependent manner. NK92 cells also exhibited a chemotactic response to medium harvested from primary hepatocyte cultures. Isolated and cultured hepatocytes express several different chemokines. Although we identified that medium from hepatocyte cultures contains specific chemokines by immunoblotting, there is potential that migration assays detected yet other chemokines and other factors such as complement components. In this report, we demonstrated that hepatocytes expressed factors that were chemoattractive for human NK92 cells and that the factors must interact with the repertoire of receptors responsible for recruitment of these cells.  相似文献   
7.
To evaluation of clinical examination for differential diagnosis of navicular region pain from other forms of palmar heel pain in the forelimb in horses the present study was undertaken. Thirty four horses with lameness referable to the palmar aspect of the hoof based on their response to the palmar digital nerves analgesia were divided into 2 groups based on their response to both distal interphalangeal joint and navicular bursa analgesia. Horses that were profoundly improved by both analgesic blocks (distal interphalangeal joint and navicular bursa) were considered to have navicular region pain whereas, all other horses were considered to have other cause of palmar heel pain. The responses to various diagnostic tests such as hoof tester, distal limb flexion and toe wedge tests were compared between the groups. For all diagnostic tests, sensitivity, specificity and positive predictive values for navicular pain were calculated. According to the present study the single most accurate diagnostic test was analgesia of the distal interphalangeal joint for navicular region pain.  相似文献   
8.
The objective was to evaluate interactions between starter protein (180 vs. 200 g/kg, DM basis) and a mixture of essential oils (EOs; containing thymol, eugenol, vanillin, limonene and guaiacol) on growth, metabolic and ruminal functions of Holstein dairy calves. In a completely randomized 2 × 2 factorial design, 48 calves, 3 days old (averaging BW 42.7 ± 1.9 kg), were allocated into groups fed the following diets: (i) 180 g/kg CP with no EO (180P‐NEO); (ii) 180 g/kg CP with EO (180P‐EO); (iii) 200 g/kg CP with no EO (200P‐NEO); and (iv) 200 g/kg CP with EO (200P‐EO). The EO was supplemented as 1 g/kg of starter DM. Calves were fed ad libitum starter diet and were weaned at day 59 of age, but diets continued until day 80. There were no interactive effects of CP and EO on intake and growth. Pre‐weaning feed efficiency tended to be increased for 200P‐EO (p = .09). Average daily gain and feed efficiency during pre‐weaning period as well as weaning weight were increased (p < .05) by EO, whereas wither height was increased by EO (p = .03) and tended to be increased for 200P vs. 180P (p = .06). Post‐weaning blood urea nitrogen concentration tended to be lower in 180P vs. 200P (p = .08). Ruminal short‐chain fatty acids concentration was greatest in 200P‐EO. The EO increased both butyrate (p = .02) and propionate proportions (p = .01) and reduced acetate proportional ratio (p < .01). Ruminal ammonia‐N was tended to be lower in calves‐fed EO (p = .05) and was lower in those fed 180P vs. 200P (p < .01). In conclusion, supplementation of the starter diet with essential oil improved weight gain, growth and feed efficiency of dairy calves, irrespective of dietary protein content.  相似文献   
9.
The aim of this study was to determine the prevalence, variability with host age, and the genotypes of species of Cryptosporidium in cattle from 15 dairy farms in Qazvin province, Iran. Fecal samples, collected from 272 cattle during May 2006 to December 2007, were characterized microscopically. Oocysts from 51 positive samples were analyzed using PCR assay of 18S SSU rRNA, restriction fragment length polymorphism (RFLP) and sequencing. We identified 72.6% of the positive samples as Cryptosporidium parvum, 17.7% as Cryptosporidium andersoni, 7.8% as Cryptosporidium bovis and 1.9% as a novel genotype of C. parvum possessing a single mutation on MboII restriction. An infection rate of 19.5% of C. parvum among 174 pre-weaned calves was significantly higher than the 3.1% among 98 post-weaned calves (P < 0.0006). This is the first report of C. bovis and the new subgenotype of C. parvum in Iranian cattle.  相似文献   
10.
Studies have shown the detection of emerging contaminants (ECs), of which pharmaceuticals are a subset, in surface waters across the United States. The objective of this study was to develop methods, and apply them, to evaluate the potential for food chain transfer when EC-containing waters are used for crop irrigation. Greenhouse experiments were performed in which select food crops were irrigated with water spiked with three antibiotics. Field experiments, at two different sites, were conducted. Select crops were irrigated with wastewater effluent known to contain ECs, EC-free well water, and Colorado River water containing trace-level ECs. The results of the greenhouse studies show the potential for uptake of one or more of the antibiotics evaluated, albeit at very low levels. In those food crops watered with wastewater effluent, only an industrial flavoring agent, N,N'-dimethylphenethylamine (DMPEA), was consistently found. None of the evaluated contaminants were found in crops irrigated with Colorado River water.  相似文献   
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