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71.
The pharmacokinetic parameters of levamisole were determined in the Caspian salmon after intramuscular (IM), oral by gavage, and oral by feed administrations. Eighty-one healthy fish in three different groups received levamisole at the dose of 25 mg/fish by each route. Blood samples were collected at time points of 0, 0.5, 1, 2, 4, 6, 12, 14, and 24 hr after administrations. Plasma levamisole concentrations were measured by a validated high-performance liquid chromatography (HPLC) assay and were analyzed using a noncompartmental approach. The mean terminal half-life was 4.56, 3.95, and 2.91 hr for IM, gavage and feed routes, respectively. The peak plasma concentration for IM, gavage, and feed routes of levamisole were 35.53, 4.63, and 8.36 µg/ml, respectively, at the time of 0.25 for IM, and 1 hr for gavage and feed. The relative bioavailability for gavage and feed routes was 54.80 and 69.30. The similar bioavailability for gavage and feed might be indicative of similar efficacy for these routes of administrations. Further studies are warranted to evaluate the absolute oral bioavailability and the effective dose in Caspian salmon.  相似文献   
72.
A greenhouse experiment (5 × 2 × 2 factorial arranged in randomized-complete-design with three replicates) was conducted to assess the combined effects of nickel (Ni) and drought stress on growth and yield parameters of canola (Brassica napus L. var. Talaye) grown on two calcareous soils of loamy and sandy clay textures. Treatments consisted of five Ni levels (0, 0.05, 0.1, 0.5 and 1 mg Ni kg?1 soil) and two levels of water status 100% and 60% field capacity (FC and 0.6FC, respectively). Growth parameters and yield components of plants decreased at drought-stress conditions. Almost all of the studied growth/yield parameters of canola grown on loamy soil were significantly more than those of the sandy clay soil, probably due to the increased capability of loamy soil for supplying the plant water/nutrient requirements. Nickel could positively affect some of the mean growth and yield parameters (e.g., grain yield) over both of the water status conditions. Nevertheless, some of the traits not only increased by Ni fertilization but also decreased compared to that of the control. The positive responses of canola was observed with higher amounts of applied Ni in the sandy clay soil than in loamy soil, e.g., the maximum grain yields of canola grown on loamy and sandy clay soils were obtained with applications of 0.5 and 1 mg Ni kg?1, respectively. Generally, results demonstrated that Ni could not mitigate the negative effects of drought stress on canola growth or yield components.  相似文献   
73.
Precision Agriculture - This research study focuses on the design of variable rate liquid fertilizer applicator which can measure the NPK status of soil and applies N, P and K nutrients...  相似文献   
74.
Background: Angiotensin II (Ang II) has an important role on cerebral microcirculation; however, its direct roles in terms of ischemic brain edema need to be clarified. This study evaluated the role of central Ang II by using candesartan, as an AT1 receptor blocker, in the brain edema formation and blood-brain barrier (BBB) disruption caused by ischemia/reperfusion (I/R) injuries in rat. Methods: Rats were exposed to 60-min middle cerebral artery (MCA) occlusion. Vehicle and non-hypotensive doses of candesartan (0.1 mg/kg) were administered one hour before ischemia. Neurological dysfunction scoring was evaluated following 24 h of reperfusion. Animals were then decapitated under deep anesthesia for the assessments of cerebral infarct size, edema formation, and BBB permeability. Results: The outcomes of 24 h reperfusion after 60-min MCA occlusion were severe neurological disability, massive BBB disruption (Evans blue extravasation = 12.5 ± 1.94 µg/g tissue), 4.02% edema, and cerebral infarction (317 ± 21 mm3). Candesartan at a dose of 0.1 mg/kg, without changing arterial blood pressure, improved neurological dysfunction scoring together with significant reductions in BBB disruption (54.9%), edema (59.2%), and cerebral infarction (54.9%). Conclusions: Inactivation of central AT1 receptors, if not accompanied with arterial hypotension, protected cerebral micro-vasculatures from damaging effects of acute stroke. Key Words: Blood–brain barrier, Brain edema, AT1 receptor, Candesartan  相似文献   
75.
Backgrounds: Most of the hepatitis C virus (HCV) infections elicit poor immune responses and 75% to 85% of cases become chronic; therefore, the development of an effective vaccine against HCV is of paramount importance. In this study, we aimed to evaluate co-administration of HCV non-Structural Protein 2 and IL-12 DNA vaccines in C57BL/6 mice. Methods: A plasmid encoding full-length HCV NS2 protein (non-structural protein 2) was generated and used to vaccinate mice. Negative control (an empty expression vector) was also employed to evaluate the background response. To investigate immune responses against vaccine, C57BL/6 mice received three doses of the vaccine with a two-week interval. Cellular immunity was assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay for lymphocyte proliferation, lactate dehydrogenase release for cytotoxic T lymphocyte (CTL) activity and cytokine assay. Results: The findings demonstrated that immunization of mice with plasmid expressing HCV NS2 induced CTL response, interferon gamma production, and lymphocyte proliferation compared to negative control. The results also demonstrated that co-administration of IL-12 with the HCV NS2 plasmid induced significantly better immune response in C57BL/6 mice. Conclusion: DNA vaccine encoding HCV NS2 is an effective candidate that can trigger CTL-based immune response against HCV. In addition, the results suggested that combining the DNA vaccine approach with immune stimulatory cytokines may significantly enhance antigen-specific immune responses. Key Words: Hepatitis C virus (HCV), NS2 protein, DNA vaccine, IL-12  相似文献   
76.
Mycoplasma conjunctivae are etiological agents of infectious keratoconjunctivitis (IKC), commonly known as pink-eye in domestic sheep, goats and other wild animals in many parts of the world. A few young Lohi lambs maintained at Livestock Experiment Station (LES), Bahadurnagar, Okara, Pakistan showed clinical signs and symptoms of conjunctivitis, keratitis, severe lacrimation and varying degree of blindness. During January to March, 2011, a total of 36 ocular swabs were collected from IKC affected animals and were processed for isolation, identification, and characterization of M. conjunctivae. Sixteen (44.44 %) out of 36 samples showed turbidity in PPLO broth. Twelve (75 %) out of 16 broth samples showed colony growth on PPLO agar. All 16 (44.44 %) out of 36 turbid broth samples, 12 (75 %) out of 16 cultured on agar plate samples, and 21 (59 %) out of 36 sheep ocular direct swab samples were found positive for M. conjunctivae through polymerase chain reaction test by using M. conjunctivae-specific primer pair McoF1 and McoR1 and detecting a 750 base pair fragment on agarose gel. Topical application of 0.5 % sterile solution of gentamycin (100 mg/ml) (Gentafar 10 %, FARVET, Netherlands) proved suitable for the treatment of IKC in Lohi lambs as all clinical signs of IKC disappeared after 5 days of treatment with this antibiotic. This is the first report about the prevalence, molecular diagnosis, and treatment of M. conjunctivae in Lohi sheep affected with infectious keratoconjunctivitis at LES, Bahadurnagar, Okara, Pakistan.  相似文献   
77.
Aetiology of mango malformation (MM) has intrigued the scientists since its inception. The objective of the study was to glean an insight into association of the fungus, Fusarium mangiferae, with different malformed regions, viz. panicle-shoot juncture, apical buds, primary and secondary peduncles, in five exotic mango cultivars. Tissue assays revealed an infection of 88.5, 84.75 and 82.5% in cvs Zill, Sensation and Tommy Atkins, respectively. Least infection of 69.75% was found in cv. Keitt. No exotic cultivar was found to be free of fungal infection. Apical buds proved to be the potential infection site of the fungus amongst the four malformed regions, hosting maximum within-tissue infection of 86.2%. Determination of F. mangiferae at proximal and distant sites of the malformed panicles exhibited maximum recovery of 82.0% at 0 cm and only 3% at >30 cm distance beneath the panicle. In the case of non-malformed panicles, an infection of 14.0% was recorded at 0 cm distance while no detection could be made from non-malformed branches. Moreover, examination of ultra-thin bud sections under Transmission Electron Microscopy (TEM) revealed inter- and intra-cellular ramification of fungal hyphae, indicating fungal ingress in malformed bud tissues of local cv. Malda. The present studies explored the sites hosting the causal fungus in mango and provide convincing evidence that F. mangiferae is responsible for turning healthy tissues into the malformed condition. These findings suggest that inoculum specific management strategies are needed in future to curb malformation disease in mango orchards.  相似文献   
78.
利用光学显微镜(LM)和扫描电镜(SEM),对新疆昆仑山2科4属10种藓类孢子进行了观察。结果表明:所研究种类孢子体积小、孢壁薄、易褶皱、纹饰明显。同科属之间,孢子的形态、直径、近极面结构,特别是外壁纹饰的形状、分布均有差异。该研究可为苔藓植物系统分类、演化及化石孢子的鉴定提供依据。  相似文献   
79.
Textiles, especially those made of natural fibers, are suitable medium for the growth of microorganisms which causes disease transmission, stink, colorful spots, and reduction in fabric strength. This research focuses on the antimicrobial finishing of cotton fabrics using colloidal solution of silver nanoparticles. Due to the difficulties of adding a new step to the finishing process of cotton textiles, efforts have been made to combine the antimicrobial treatment with the conventional finishing processes. For this purpose two chemical finishes of Fixapret ECO as a crosslinking agent and Cellofix ME as a resin former have been used in anti crease finishing of cotton fabric and their effects were evaluated. The properties of the samples have been investigated by measuring the resistant of samples against bacteria, crease recovery angle, abrasion, and washing fastness. The results showed that treated samples by pad-dry method have the best antibacterial effect with a direct relation between the increase in drying temperature and antibacterial properties. However, the washing and abrasion fastness were not at the acceptable level. Co-application of the colloidal solution of silver nanoparticles with the crease resistant materials improved both fastness properties while at the same time limited the direct contact between the nanoparticles and the bacteria so the antibacterial efficiency was reduced. Subsequently, it was concluded that the antibacterial finishing method should be selected according to the end uses. In addition, antibacterial treatment could be one of the multi-purpose finishes for cotton fabric.  相似文献   
80.
BACKGROUND: Biopesticides based on Beauveria bassiana (Bals.) Vuillemin hold great promise for the management of a wide range of insect pests. The conidia in the biopesticide formulation require an adjuvant to protect them from photoinactivation by sunlight. The suitability of Tinopal, an optical brightener used as sunscreen for baculovirus formulations, for use with B. bassiana was assessed. The aim was to study the effect of Tinopal on the growth and photoprotection of B. bassiana, and its effect on the susceptibility of insects to B. bassiana. RESULTS: Tinopal was found to have no adverse effect on the growth of B. bassiana. It was found to confer total protection (approximately 95% conidial germination at 10 g Tinopal L(-1)) from sunlight up to 3 h of exposure, and a better survival rate than controls even up to 4 h. Helicoverpa armigera Hübner larvae fed on diet with 5 g kg(-1) Tinopal were found to have reduced growth. The duration of the larval stage increased by 3-4 days in 1 and 5 g kg(-1) Tinopal treatments. Among the moths that emerged from larvae fed on diet with 5 g kg(-1) Tinopal, a significantly high number were malformed compared with controls. The larvae that were fed diet with Tinopal showed quicker and higher mortality and required a lower effective lethal dose (LC(50)) than the controls. Tinopal was found to have a synergistic effect with B. bassiana in causing insect mortality. CONCLUSIONS: Tinopal was found to be a suitable adjuvant for B. bassiana-based biopesticide formulations. It conferred tolerance to sunlight and caused stress in the insect, leading to a synergistic effect with B. bassiana.  相似文献   
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