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21.
In order to study the effects of salinity, rootstock, and position of sampling on macronutrient concentration of pomegranate (Punica granatum L.) cv. “Gabri,” a factorial experiment was conducted based on completely randomized design with 0 and 70 mM sodium chloride and calcium chloride (1:1), three graft combinations (Gabri non-grafted as a control, Gabri/Tab-o-larz, and Gabri/Malas-e-yazdi), and two positions of sampling (lower half and upper half shoot), with three replications. The results showed that mineral concentration of sodium, chloride, calcium, and potassium in shoot and root increased while that of magnesium decreased with salt treatment. The graft combination of Gabri on Tab-o-Larz rootstock had the lowest of sodium and chloride levels in the lower half shoot. Also, calcium concentration in the lower half shoot and potassium concentration in the upper half shoot were higher in the graft combination of Gabri on Tab-o-Larz rootstock. These results imply that Tab-o-Larz rootstock restricts the uptake or transport of sodium (Na) and chloride (Cl) from root to shoot; furthermore, it can be used as a salt-tolerant rootstock for pomegranate cv. Gabri.  相似文献   
22.
In order to study effects of sodium bicarbonate (NaHCO3) stress in irrigation water on photosynthetic characteristics and iron (Fe) and sodium (Na+) translocation content of pomegranate plants, a factorial experiment was conducted based on completely randomized design with three cultivars of pomegranate (“Gorch-e-Dadashi,” “Zagh-e-Yazdi,” and “Ghermez-e-Aliaghai”) and four concentrations of NaHCO3 (0, 5, 10, and 15 mM), with three replications. The results of plant analysis indicated that NaHCO3 affected chlorophyll index, Fv/Fm, and performance index (PI) in upper and lower leaves of shoots and also the translocation of Na+ and Fe. The results also showed that Fe translocation from root to shoot reduced at 15 mM level of NaHCO3. The highest Na translocation and the lowest Fe translocation were observed in Zagh-e-Yazdi and Ghermez-e-Aliaghai cultivars, respectively. The ratio of sodium/potassium (Na+/K+) in stems was higher than that in roots and leaves, and the observed chlorophyll content of upper leaves was also lower than that of lower leaves. Based on the measured parameters Gorch-e-Dadashi cultivar showed less relative sensitivity than other cultivars to NaHCO3 of irrigation water through maintaining the lower Na+ transport to the shoots, and improvement of Fe transport to shoots.  相似文献   
23.
1. Xanthine oxidase (XO) has many physiological functions associated with the synthesis of both antioxidant (uric acid: UA) and numerous oxidants (e.g. H2O2), which makes it an important regulator of the cellular redox potential involving organogenesis. The ontogenetic study of hepatic and renal XO makes a better understanding of the putative role of this enzyme in the development of these tissues.

2. Developmental changes of gene expression of xanthine oxidoreductase (XOR), XO activity and UA content of liver and kidney tissues in both broiler and layer chicken embryos were examined during incubation d 14–21.

3. In both strains, hepatic XOR gene expression peaked on d 21 while renal XOR gene expression did not change.

4. The XO activity was higher in kidney than liver in both strains. Hepatic XO activity of both strains peaked on d 18 and thereafter was decreased on d 21. Renal XO activity peaked on d 18 and from then on did not show any significant changes until d 21 in both strains.

5. The UA content was higher in kidney vs. liver in both strains. The hepatic and renal UA values of the both strains increased significantly from d 14 to d 21.

6. The present results showed dissimilar behaviour of XOR gene expression, XO activity and UA content of liver and kidney tissues in both broiler and layer chicken embryos.  相似文献   

24.
Mixed infections caused by enteric pathogens such as bacteria, virus, protozoa and helminthes were reported in different literatures. This report also describes the co-infections caused by Vibrio cholerae O1 Ogawa EL Tor with Shigella dysenteriae in a patient. A 36-year-old man was admitted in Fatemeh Zahra Hospital of Bushehr Iran with fever, vomiting and dysentery. His stool sample was cultured, for identification purposes TCBS, XLD and other media were used. V. cholerae and S. dysenteriae were identified. Both species were resistant to ampicillin and sensitive to nalidixic acid and trimethoprim-sulfamethoxazol. Shigella was resistant to tetracycline. The results of the study showed that places where diarrheal diseases especially cholera are endemic, it is better to examine for those patients with dysentery for the presence of the V. cholerae O1. That will prevent the spread of pathogenic organism in the community.  相似文献   
25.
Three different suture patterns (simple interrupted, interrupted horizontal mattress, subcuticular) were placed in a full thickness incision (skin and body wall) of 18 goldfish (Carassius auratus). After 14 days all fish were euthanized using benzocaine solution. The tissue reactions were evaluated by gross visual inspection and histopathological examination. The superficial inflammatory reactions were graded on a scale from 0 (no inflammation) to 3 (severe inflammation). The inflammatory response in histological examination was graded on a scale from 0 (no inflammatory response or normal skin tissue) to 5 (severe inflammatory response and necrosis). The interrupted horizontal mattress induced a moderately severe to severe inflammatory response and necrosis (grades 4–5) but the subcuticular suture induced a very mild to mild inflammatory response (grades 0–1). The simple interrupted suture induced a moderate to moderately severe inflammatory response (grades 2–4). In conclusion, results showed that a subcuticular suture is the most appropriate to use in the closure of a full thickness body wall incision.  相似文献   
26.
Background: Cryopreservation of pre-antral follicles is a hopeful technique to preserve female fertility. The aim of the present study was to evaluate reactive oxygen species (ROS) and total antioxidant capacity (TAC) levels of mouse vitrified pre-antral follicles in the presence of alpha lipoic acid (ALA). Methods: Isolated pre-antral follicles (140–150 µm in diameter) were divided into vitrified–warmed and fresh groups. Each group was subjected to in vitro maturation with or without ALA for 12 days, followed by adding human chronic gonadotropin to induce ovulation. In vitro fertilization was performed to evaluate their developmental competence. In parallel, the amount of ROS and TAC were assessed after 0, 24, 48, 72, and 96 h of culture by 2'',7''-dichlorofluorescin assay and ferric reducing/antioxidant power assay, respectively. Results: The respective rates of survival, antrum formation, and metaphase II oocytes were significantly higher in ALA-supplemented groups compared to the groups not treated with ALA. TAC and ROS levels were significantly decreased and increased, respectively during the culture period up to 96 h in the absence of ALA in both vitrified and non-vitrified samples. However, with pretreatment of ALA, TAC levels were increased significantly and remained constant up to 96 h in vitrified-warmed pre-antral follicles, while ROS levels completely returned to the level of starting point after 96 h of culture in the presence of ALA. Conclusion: Pretreatment of ALA positively influences development of pre-antral follicles in vitrified and non-vitrified samples through increasing follicular TAC level and decreasing ROS levels. Key Words: Vitrification, Pre-antral follicle, Alpha lipoic acid (ALA), Reactive oxygen species (ROS), Total antioxidant capacity (TAC)  相似文献   
27.
Samples of partially oriented yarn (POY) PET fibers were uniaxially drawn at temperatures below, near, and above the glass transition temperature at a constant draw ratio before exposure to supercritical carbon dioxide (scCO2) in the presence of tension at a temperature of 80 °C and a pressure of 220 bar. The effects of drawing temperature and scCO2 exposure on structural changes and on mesomorphic transitions, in particular, were investigated using differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), and birefringence and density measurements. A good correlation was obtained among the results obtained from various techniques. Results indicated that the development of a transient mesophase structure depended strongly on process temperature. By drawing PET fibers in the samples at temperatures below the glass transition (cold-drawing), a mesophase structure developed in which the highly extended chains played a key role in structural changes incurred. Meanwhile, exposure to scCO2 led to the plasticization of the samples accompanied by their reduced glass transition and cold crystallization temperatures. This process also gave rise to the appearance of a second melting peak at about 135 °C that is related to the melting of imperfect and thin crystals, thereby inducing structural changes in the treated fibers. In the case of samples subjected to cold drawing and to scCO2 exposure, the transformation of the mesophase structure into the crystalline phase was found to be strongly affected by scCO2 exposure, while this same effect was negligible in the case of hot drawn samples.  相似文献   
28.
This experiment was conducted in split plots based on randomized complete block design with three replications. Three crop sequences: (R1): chickpea, sunflower, wheat, and canola; (R2): green manure, chickpea, green manure, wheat, green manure, and canola; (R3): canola, wheat, and canola were used as main plots. Sub plots consisted of six methods of fertilization: (N1): farmyard manure; (N2): compost; (N3): chemical fertilizers; (N4): farmyard manure + compost; (N5): farmyard manure + compost + chemical fertilizers; and (N6): control. Results showed that the enzyme activities were higher in the N4 treatment. The highest amount of acid phosphatase, protease, dehydrogenase activity, and grain yield was observed in R2 sequence. The highest urease activity (58.6 µg g?1 h?1) was obtained in R2N4 treatment. In R2N4 treatment using in-farm inputs, a non chemical fertilizer system can be carried out to improve soil biological activity.  相似文献   
29.
30.
Since 1998, H9N2 AI outbreaks have been one of the major problems in Iranian poultry industry. The association of high mortality and case report of H5N1 and H9N2 influenza virus in wild birds in recent years raised the specter of a possible new genetic modified AI virus. In this study, we do phylogenetic analysis on Full- length Nonstructural (NS) genes of seven H9N2 Isolates from Broilers in Iran, Tehran province during 1998-2007. Phylogenetic analysis clearly shows that Iranian H9N2 isolates gene pools, corresponding to just NS allele A. Comparison of nucleotide sequences of isolated viruses revealed a substantial number of silent mutations, which results in high degree of homology in amino acid sequences. In addition, the cluster of Iranian H9N2 isolates could be subdivided into two subgroups, which matched their times of isolation especially around 2006 time line. The high degree of similarity between the NS genes of the Iranian H9N2 isolates supports the hypothesis that these genes originated from a single predecessor. Present result provides useful molecular epidemiological data to understand the dynamics of H9N2 evolution during 9 years in Iran and support earlier phylogenetic observations.  相似文献   
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