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131.
Vajiheh Dorostkar Majid Afyuni Amir Hossein Khoshgoftarmanesh Mohammad Reza Mosaddeghi Farhad Rejali 《Archives of Agronomy and Soil Science》2016,62(3):429-443
Soil salinity and arbuscular mycorrhizal fungi (AMF) influence the soil hydrophobicity. An experiment was performed to determine the effects of soil salinity and AMF species on soil water repellency (SWR) under wheat (Triticum aestivum L.) crop. Six AMF treatments, including four exotic species (Rhizophagus irregularis, Funneliformis mosseae and Claroideoglomus claroideum, a mix of three species), one mix native AMF species treatment and an AMF-free soil in combination with four salinity levels (1, 5, 10, and 15 dS m?1) were used. The soil repellency index (RI) increased with salinity increment ranging from 2.4 to 10.5. The mix of three exotic and native AMF treatments enhanced the RI significantly compared to AMF-free soil in all salinity levels with one exception for native treatment at 1 dS m?1. Among individual AMF species, the C. claroideum treatment at 10 dS m?1 increased the RI by 67% compared to AMF-free soil. The native AMF treatment was more efficient in root colonization, glomalin production and SWR development at 10 and 15 dS m?1, compared to exotic species. In addition to the net positive effect of salinity on SWR, the AMF influences on the RI were greatly dependent on salinity levels. 相似文献
132.
Experimental transmission of scrapie agent to susceptible sheep by intralingual or intracerebral inoculation
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Amir N. Hamir Robert A. Kunkle Marie S. Bulgin Robert G. Rohwer Luisa Gregori Juergen A. Richt 《Canadian journal of veterinary research》2008,72(1):63-67
Scrapie, a transmissible spongiform encephalopathy (TSE), is a naturally occurring fatal neurodegenerative disease of sheep and goats. This study documents survival periods, pathological findings, and the presence of abnormal prion protein (PrP(Sc)) in genetically susceptible sheep inoculated with scrapie agent. Suffolk lambs (AA/RR/QQ at codons 136, 154, and 171, respectively) aged 4 mo were injected by the intralingual (IL) or intracerebral (IC) route with an inoculum prepared from a pool of scrapie-affected US sheep brains. The animals were euthanized when advanced clinical signs of scrapie were observed. Spongiform lesions in the brain and PrPsc deposits in the central nervous system (CNS) and lymphoid tissues were detected by immunohistochemical and Western blot (WB) testing in all the sheep with clinical prion disease. The mean survival period was 18.3 mo for the sheep inoculated by the IL route and 17.6 mo for those inoculated by the IC route. Since the IC method is occasionally associated with anesthesia-induced complications, intracranial hematoma, and CNS infections, and the IL method is very efficient, it may be more humane to use the latter. However, before this method can be recommended for inoculation of TSE agents, research needs to show that other TSE agents can also transmit disease via the tongue. 相似文献
133.
Oskoii SB Kohyani AT Parseh A Salati AP Sadeghi E 《Fish physiology and biochemistry》2012,38(4):1029-1034
This study was conducted to evaluate the effects of Echinacea purpurea (EP) on growth and some hematological and blood biochemical indices of rainbow trout fingerlings. A basal diet was supplemented with 0 (control), 0.25, 0.5, 1, and 2 g EP kg?1 to formulate five experimental diets. Each diet was randomly allocated to triplicate groups of fish with an initial average weight of approximately 8 g. After 8 weeks of feeding trial, fish fed diets with 0.25 and 0.5 g EP kg?1 showed highest final weight and SGR and fish fed with the control diet indicated the lowest final weight and SGR. There was a significant (P < 0.05) decrease in FCR between the control group and the groups fed with diets of 0.25 and 0.5 g EP kg?1. Biochemical parameters such as serum total protein content, albumin content, globulin content, and albumin/globulin ratio in the fish were evaluated. There were significant differences between hematological parameters including RBC, WBC, HB, lymphocyte, and neutrophil percentage in fish fed with dietary nucleotide compared with control treatment (P < 0.05). The results suggest that EP administration at 0.25 and 0.5 g EP kg?1 exerted positive effects on growth and biochemical and hematological indices in rainbow trout. 相似文献
134.
Imadeldin E. Aradaib Osama H. Omer Babiker B. Abbas Hamid O. Bushara Khitma H. Elmalik Amir M. Saad Bennie I. Osburn Martin G. Taylor 《Preventive veterinary medicine》1995,21(4):339-345
Six calves were immunized with whole egg antigen of Schistosoma bovis emulsified in Freund's adjuvant. The immune response was monitored by agar-gel immunodiffusion (AGID) and enzyme-linked immunosorbent assay (ELISA). Using AGID and ELISA, antibodies to whole egg antigen were detected in sera from all immunized calves, but not in sera from control calves. The immunized calves and six control calves were challenged 6 months after the beginning of the immunization with 20 000 cercariae of Schistosoma bovis administered percutaneously to the shaved tail. There was no significant difference between the immunized and the control calves as judged by fecal and tissue egg counts, worm recovery and hematological parameters. There was a lack of association between antibody production and protection. 相似文献
135.
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137.
In this study, the influence of press cycle time and resin content (RC) on some of the physical and mechanical properties of single-layer particleboard manufactured from the low-quality raw materials were determined. Eucalyptus (Eucalyptus camaldulensis), mesquite (Prosopis juliflora), saltcedar (Tamarix stricta) and date palm (Phoenix dactylifera) wood, which is underutilized invasive species in southern parts of Iran, were used as alternative raw materials for particleboard manufacturing. Variable factors were as resin content (9, 10 and 11%) and press time (PT) (4, 5 and 6 min). Other parameters such as type of resin (UF), hardener content (2%), type of hardener (NH4Cl), press-closing time (4.5 mm/s), board density (0.75 g/cm3), press pressure (30 kg/m2) and press temperature (160 °C) were held constant. The experimental panels were tested for their mechanical strength including modulus of elasticity (MOE), modulus of rupture (MOR), internal bonding (IB) and physical stability properties (thickness swelling) according to the procedures defined by European Union (EN) Standard. Overall results showed that most panels made from above-mentioned materials exceed the EN Standards for IB, MOE and MOR. The mechanical properties of particleboard were improved as the resin content increased from 9 to 11%. The results indicated that the polymerization of resin and wood is better at 11% resin content and 5 min of press time. However, thickness-swelling (TS) values were higher (poor) than requirements. Panels made of mesquite, saltcedar and date palm with a resin content of 11% and pressed for 5 min is adequate for general uses while eucalyptus with a resin content of 11% and pressed for 6 min is suitable for interior decoration. 相似文献
138.
Khaki AA Zarrintan S Khaki A Zahedi A 《Pakistan journal of biological sciences: PJBS》2008,11(5):692-701
In the industrial world, almost everyone is unavoidably exposed to ambient electromagnetic field (EMF) generated from various technical and household appliances. Controversy exists about the effects of EMF on various tissues of the living bodies. Seminal vesicles as one of these accessory glands play an important role in natural seminal fluid formation and the effects of EMF on its tissue is worthy of investigation. In order to examine this 30 rat were selected and kept for one weeks in quarantine and 15 (experimental group) were exposed to 50 Hz (non-ionizing radiation) during postnatal life for 2 months. The materials were processed and observed under a light and transmission electron microscope. In the experimental rats epithelial and basal cells showed significant destructions presented by heterochromatin and dense nuclei. Cell debris and abnormal areas was recognizable in the stromal connective tissue. Obvious vacuolization was present within the epithelial cell cytoplasm and also between the cellular organelles. The nuclei of the endothelial cells of the blood vessels were more rigid and endothelial cell cytoplasm contained a lot of vacuoles and pinoctotic vesicles. The results suggested that EMF exposure may cause profound changes in the vesicle seminal tissues. Therefore exposure to EMF may result in pathological changes that lead to sub fertility and infertility. 相似文献
139.
The stability, crystallization, and melting behavior of canola stearin (CaSt) solid lipid nanoparticle dispersions (SLN) and canola oil-in-water emulsions (COE) with 10 wt % Poloxamer 188 (P188) or Tween 20 (T20) with and without 0.1 wt % β-carotene (BC) were investigated. Particles or droplets with diameters in the range of 115 nm were formed and stable for up to 90 days at 4 or 20 °C. Polymorphism was affected by surfactant type; that is, only β versus both β' and β were observed for the P188 and T20 SLN, respectively. According to Cryo-TEM, the emulsions and SLN were spherical versus platelet-like structures, respectively, with differences observed between SLN with P188 or T20. More surfactant was interfacially adsorbed in the SLN versus COE. Incorporation of BC at 0.1 wt % had no impact on SLN or COE size, polymorphism, or melting behavior. Less BC degradation was observed for the SLN versus COE and during storage at 4 versus 20 °C (p < 0.05). 相似文献
140.
Amir Hayat Taj Muhammad Jahangir Muhammad Yar Khuhawar Malik Alamgir Amna Jabbar Siddiqui Syed Ghulam Musharraf 《Journal of Cereal Science》2014
A selective and sensitive HPLC method for the simultaneous determination of gamma amino butyric acid (GABA) and lysine in Pakistani rice varieties was developed. Both analytes were detected in rice varieties as Schiff base derivatives with 2-hydroxynaphthaldehyde. The derivatives were analyzed on a reverse phase C-18 column with Diode Array Detector (DAD) at 254 nm. The calibration curves were found linear over a concentration range of 3.83–34.58 μg/mL for GABA and 5.16–48.68 μg/mL for lysine with a correlation coefficient of 0.998 for both standards. GABA and lysine contents were found higher in brown rice varieties (4.1–6.58 mg/100 g for GABA and 15.1–27.6 mg/100 g for lysine) than the polished varieties (0.32–0.47 mg/100 g GABA and 13.1–19.8 mg/100 g lysine). This method could be used for separation and quantification of GABA and lysine simultaneously in food samples, especially in cereal seeds. 相似文献