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1.
An epidemiological study to examine the sero-prevalence of zoonotic visceral leishmaniosis (ZVL) among domestic and wild canines in endemic foci of Iran was carried out during 1999-2003 to assess the distribution of the disease and the possible association between infection in dogs, wild canines and people. Anti-leishmanial antibodies were detected by the direct agglutination test (DAT). Parasitological study was performed for all captured wild canines and were detected in some of the seropositive dogs with specific clinical signs (n=107). Serum samples (n=1568) were collected from domestic dogs in villages that are known endemic foci of human visceral leishmaniosis (HVL). Wild canine sera were collected from jackals (Canis aureus, n=10), foxes (Vulpes vulpes, n=10) and wolves (Canis lupus, n=10). Of the 1568 serum sampled collected from domestic dogs, 222 (14.2%) were positive by DAT (1:320 and above). No statistically significant difference was found between male (15.2%) and female (11.8%) sero-prevalence (P=0.083). Dogs of 8 years and above showed the highest sero-prevalence (40.6%). Only 23.9% of the seropositive domestic dogs had clinical signs. Parasitology and serology tests that were performed in 30 wild canines showed 10% these animals were infected by Leishmania infantum. Ten out of 11 Leishmania spp. isolated from the dogs and wild canines were identified as L. infantum and one other as L. tropica by molecular and biochemical techniques. For the first time in Iran, L. infantum and L. tropica were isolated from viscera of both a wolf and a domestic dog.  相似文献   
2.
In the present study, the interactive effects of methyl jasmonate (0, 0.01, and 0.1 mM) and cadmium chloride (0 and 500 μM) on growth, biochemical, and physiological parameters of soybean plants were investigated. The plants were first treated with methyl jasmonate and then exposed to cadmium stress. Cadmium reduced shoot dry weight and total chlorophyll contents and increased lipid peroxidation in leaves. Methyl jasmonate, especially at a lower level (0.01 mM), significantly alleviated the cadmium damage to shoot dry weight and total chlorophyll contents and also, reduced lipid peroxidation. The increase in catalase and polyphenol oxidase activities were also observed under cadmium stress. The activity of ascorbate peroxidase was enhanced by methyl jasmonate under no stress and cadmium stress. However, peroxidase activity increased under no stress conditions. Based on our results it could be concluded that the application of methyl jasmonate caused significant alleviation of cadmium damages to soybean plants.  相似文献   
3.
Graphene nanoplatelet (GnP) was chemically functionalized by amine groups for improvement of compatibility in poly(methyl methacrylate) (PMMA)/poly(ethylene oxide) (PEO) blend. PMMA/PEO (90/10) nanocomposites with non-functionalized GnP and functionalized GnP (FGnP) were prepared by solution casting method. Successful grafting of amine groups on the GnP surface was confirmed by Fourier transform infrared (FT-IR) and X-ray diffraction (XRD) analysis. The Transmission electron microscopy (TEM) images showed that the dispersion state of FGnP was better than that of GnP in PMMA/PEO nanocomposites. The effects of FGnP and GnP on rheological, thermal and electrical properties of PMMA/PEO nanocomposites were investigated by various methods. The results indicated that the FGnP-based nanocomposites had higher storage modulus, glass transition temperature and thermal stability as compared to the GnP-based nanocomposites. The electrical conductivity of the nanocomposites with FGnP was better than that of GnP-based nanocomposites. The higher conductivity was attributed to homogeneous and well dispersion state of FGnP in PMMA/PEO nanocomposites.  相似文献   
4.
5.
A mesquite Rhizobium isolated from the Sonoran Desert (strain AZ-M1) and a commercial mesquite Rhizobium obtained from the Nitragin Company (strain 31A5) were chosen as superior strains from among many evaluated in a screening study of the efficiency of mesquite rhizobia. Both strains were fast-growing and acid-producing in denned media. The desert strain AZ-M1 had the shortest mean generation time of 3.5 h. Strain 31A5 grew better in broth amended with various sugars and amino acids, but generally produced less acid. The desert strain showed greater resistance to various antibiotics than did 31A5. In a greenhouse study N applied at high rates inhibited N2 fixation when either strain was used as inoculant for mesquite seed. At low N rates, AZ-M1 fixed more N than 31A5. Total N, nodule weight, C2H2 reduction, mesquite shoot weight and root weight were all significantly increased when AZ-M1 was the applied inoculant. This study shows that the mesquite Rhizobium AZ-M 1 isolated from the Sonoran Desert is infective and effective on mesquite seedlings. Fast growth rate, acid production and high resistance to antibiotics in laboratory media may indicate the adaptation of this organism to its microbial niche in the Sonoran Desert.  相似文献   
6.
Viral haemorrhagic septicaemia (VHS) is one of the most important viral diseases in rainbow trout that has caused great losses to Iranian rainbow trout aquaculture industry in the last 3 years. Therefore, rapid and reliable diagnosis of VHS virus infections is of great importance. An enzyme linked immunosorbent assay (ELISA) method was performed to study serum antibodies against viral haemorrhagic septicaemia virus (VHSV) using recombinant fragments of their N protein. For this purpose, the virus was first isolated from an infected farm. A part of the nucleocapsid (1–505 bp) gene was amplified by RT‐PCR using specific primers. The amplified fragment was ligated to pMALc2x vector and transferred to DH5α strain of Escherichia coli. Then, recombinant plasmids were tested for protein expression in E. coli Rosetta strain. SDS‐PAGE analysis indicated the production of a recombinant protein with an expected molecular weight of 61 KDa. Analysis of trout serum samples from seven previously infected farms and two VHS free farms showed that the designed ELISA method was effective in diagnosing the infected fish. The results revealed that the developed serological assay using designed ELISA based on recombinant protein (N) has the potential to be used in monitoring studies and to determine the prevalence of VHS in rainbow trout farms. The present data allow evaluating the levels of nonneutralizing antibodies without crude virus preparations.  相似文献   
7.
Self-compatibility was examined in 22 almond samples that were selected based on their generic and physiological characteristics. Polymerase chain reaction was also done with consensus primers. Pollen tube growth and nut set analyses were carried out on partially bagged limbs after self-pollination treatment. In spite of the fact that all genotypes had the S f-allele and pollen tube growth were similar, nut set exhibited an alternate year characteristic that ranged from 16.2% to a maximum of 24.7%. This was the highest treatment after self-pollination. Difference existed between genotypes could be due to the genetic constitution of each genotype, is explored in set that is diminished by inbreeding, which diminish gene aggregation in different members of a progeny. In addition, flower morphology could also influence set in bagged limbs. Furthermore, with regard to flower sterility and bud density in relation to both pollination success and ecological condition availability, these traits must be considered when examining production in self-compatible almond orchards, e.g.,—the impacts accompanying inbreeding and effective autonomous self-pollination.  相似文献   
8.
Supplementing the extender with antioxidants with low molecular weight can enhance the quality of the post-thaw sperm during the freezing process. This study was aimed at determining the impacts of 3,4-dihydroxyphenyl glycol (DHPG) on the spermatozoa of the canine undergoing freeze-thawing process. In this study, 24 ejaculates were obtained from three mixed-breed dogs and were diluted in a Tris-based extender. The diluted semen was divided into aliquots for supplementation of 10, 30, 50 and 70 µg/ml of DHPG, control (without antioxidant) and control sham (DMSO). After being extended, the semen was equilibrated at a temperature of 4°C and then transferred to the straws and kept 4 cm above the liquid nitrogen for 20 min and was finally immersed in the liquid nitrogen. They were cryopreserved for seven days; then, sperm parameters including sperm motility evaluation, motility characteristics, viability, DNA and plasma membrane integrity, total antioxidant capacity (TAC), reduced glutathione content (GSH), antioxidant enzymes (superoxide dismutase [SOD], catalase [CAT] and glutathione peroxidase [GPx]) activity malondialdehyde (MDA) levels were evaluated. This study showed that spermatozoa cryopreservation with 50, 30 and 70 µg/ml of DHPG concentrations had better progressive motility, Curvilinear Velocity, Linearity, viability, intact plasma membrane and the levels of TAC, GPx and GSH were higher than the control group. The 50, 30 and 70 µg/ml of DHPG concentrations led to the significant decrease of DNA damage compared to the control group. Total motility, average path velocity, straight-line velocity and CAT activity were significantly improved in 30 and 50 µg/ml of DHPG concentrations, compared to the control group. Also, the 50 and 30 µg/ml of DHPG concentrations, decreased MDA levels compared to the other groups, significantly. In conclusion, our study showed that the addition 50 µg/ml of DHPG to the canine semen extender improved the semen characteristics and oxidative markers in the cryopreservation process.  相似文献   
9.
Assisted phytoremediation procedures have been widely employed as soil removal instrument of heavy metals from contaminated soils. Rhizosphere processes have a major impact on pb and Zn availability and its fractions in soils. The present study evaluates the effects of EDTA, citric acid (CA) and poultry manure extract (PME) on bioavailability and fractionation of pb, Zn in both the rhizosphere of sunflower (Helianthus annuus L.) and bulk soil. EDTA and CA were added to soils at the rates of 0, 0.5 and 1 mmol kg?1 soil and PME at 0, 0.5 and 1 g kg?1 soil as factorial in a completely randomized pattern with three replicates in greenhouse condition. Results showed that chelator application had a significant impact (p < 0.05) on pb, Zn extraction by different extractants and its fractions in soils. The order of concentrations of pb, Zn present in different fractions in soil treated by chelators was: oxides-bounded fraction > residual fraction > OM-bounded fraction > carbonate-bounded fraction > exchangeable fraction. Biochemical soil characteristics in the sunflower rhizosphere change resulting from its roots contributing to pb, Zn decline in mobile soil fractions, and change in soil pb, Zn fractions that are generally regarded as more stable.  相似文献   
10.
The competitiveness of a mesquite Rhizobium (AZ-M1) and its ability to survive in desert soils was compared to a selected commercial strain (31A5). In a greenhouse study, the native isolate out-competed strain 31A5 in nodule occupancy, when applied as a mixed inoculant to seed germinated and grown in sand culture, and irrigated with N-free nutrients. A high incidence of nodule double occupancy was found when double strain inoculants were used. The survival rate of the two strains was tested in three desert soils in a controlled laboratory study. The desert strain AZ-M1 grew and survived in all the soils for 1 month. The commercial strain 31A5, did not grow, and the population decreased in 14 days from 108 cells g?1 dry soil to below 104 cells g?1. Both strains survived to a lesser extent in a saline-sodic soil. A significant morphological change from a rod to a coccus was observed 2 days after strain 31A5 had been introduced into the desert soils.  相似文献   
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