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1.
We examined whether mutation of the platelet‐derived growth factor receptor protein tyrosine kinase (PDGFR)‐α and PDGFR‐β genes contributes to their overexpression in canine vascular tumours. Genomic sequences of trans‐ or juxtamembrane regions of PDGFR‐α and PDGFR‐β were analysed with immunohistochemical staining and polymerase chain reaction‐direct sequencing using DNA from paraffin‐embedded neoplastic tissues of 27 hemangiosarcomas (HSAs) and 20 hemangiomas (HAs). Immunohistochemically, 75% of the HA cases were positive for PDGFR‐α and almost most of the HA cases were negative for PDGFR‐β. Of the HSA cases, 55.6% were negative for PDGFR‐α and 63% were strongly positive for PDGFR‐β. Among the HA cases, 1 missense mutation was detected in PDGFR‐α exon 18 and 1 in PDGFR‐β exon 17. Two HSA cases had missense mutations in exon 14 and 1 in exon 17 of PDGFR‐β. Thus, genomic mutation of trans‐ or juxtamembrane regions of PDGFRs was not the main mechanism driving the activation of receptors in HSA and HA.  相似文献   
2.

In the North Nile Delta of Egypt, the impacts of overplanting paddy rice on water delivery performance have not been discussed quantitatively. Further, the amount of water that could have been saved if farmers would follow the planned area is unknown. In this study, water delivery performance was assessed by comparison of actual paddy rice planting and the government’s planned conditions. For both conditions, performance indicators relating to adequacy, equity, and dependability were analyzed across six locations in conjunction with the branch canal water level in 2013 and 2014. Based on the difference between the actual water supply and planned water demand, the amount of water that could have been saved for downstream uses was calculated. The average adequacy for the investigation period was good at one location, fair at 2 locations, and poor at 3 locations in both years. Further, adequacy under both actual and planned conditions was poor in late July at all locations. The planned adequacy and dependability downstream and equity among locations improved compared to the actual condition in both years. Under the condition that paddy rice area is the upper limit planned by the government, about 12.3% and 9.6% of water could be potentially saved in each year. The difference between actual and planned water delivery performance is caused by the branch canal’s low water level. Control of overplanting paddy rice and coordination of water distribution among water user associations would improve stable water level in the canal and, eventually, water delivery performance.

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3.
Reports on the species of Fasciola present in the Nile Delta, Egypt, appear controversial. Some authors reported the presence of both Fasciola gigantica and Fasciola hepatica, others reported F. gigantica only and mentioned that F. hepatica was found only in imported animals.This study was an attempt to identify the species of Fasciola flukes collected from locally bred animals. Morphologic, morphoanatomic, morphometric, and chemotaxonomic criteria of the fluke isolates were studied. Speciation based on morphologic and morphometric data was not decisive due to overlap in the values of most measurements. Morphoanatomic data proved the presence of both the species, and isoelectric focusing (IEF) of fluke soluble protein confirmed the presence of both F. gigantica and F. hepatica in Egypt.  相似文献   
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4-Nonylphenol (NP) toxicity in fish attracts much attention due to its ability in targeting several organs; however, the researches regarding its potential hepatotoxicity are conflicting and still require further investigation. Therefore, the objective of this study is to focus on this issue from the histophysiological point of view using NP intoxicated African catfish (Clarias gariepinus) as a model of hepatotoxicity. Twelve adult fish (6 per group) were divided into two groups; the first was considered as a control and the second was exposed to NP dissolved in water at a dose of 0.1 mg/kg BW for 3 weeks. A significant reduction in the hepatic alanine aminotransferase, aspartate aminotransferase, and lactate dehydrogenase levels was observed in NP-exposed fish. Concerning the oxidant/antioxidant balance, a significant depletion in superoxide dismutase, catalase, and glutathione peroxidase was found along with a significant elevation in total peroxide and malondialdhyde. The histopathological examination of the hepatic tissues revealed that NP had marked hepatotoxic effects including hepatitis, centrilobular and focal hydropic and fatty degeneration, fatty change (steatosis), hepatic coagulative necrosis, and nuclear alterations in addition to apoptosis of hepatocytes and necrosis of endothelial cells. Depletion of the glycogen and increased in pigments (lipofuscin and hemosiderin) content in the hepatocytes were also recorded. Hemosiderosis and proliferation of the connective tissue around the blood vessels and branches of bile ducts and in the portal areas were also observed. In light of these findings, it was concluded that NP has a well-defined hepatotoxic impact paving the road towards other studies to investigate other detrimental cyto-physiological influences of this aquatic pollutant.  相似文献   
7.
One step thermochromic pigment printing and antibacterial functionality of cotton (100 %) and cotton/polyester blend (50/50 %) were demonstrated in this study. The improvement in antimicrobial activity against G+ve (Bacillus cereus) and G-ve (E. coli), and pigment printability were achieved by inclusion of Ag-NPs (30 g/kg) into pigment printing paste followed by printing and microwave curing at 700 W for 5 min. Modes of interactions were proposed, and surface modification was also confirmed by SEM and EDX analysis that proved the presence of Ag-NPs in cotton and cotton/ polyester blended samples. The results indicated that the colour fastness to wash and rubbing was excellent, the surface roughness reduced, and exhibited good antibacterial activity against Bacillus cereus and E. coli bacteria.  相似文献   
8.
Efficient water delivery systems such as drip irrigation can contribute towards increasing crop yield potential, improving crop water and fertilizer use efficiency. However, critical management considerations such as subsurface drip irrigation are necessary to attain improved irrigation efficiencies and production benefits particularly under arid regions. The objective of this study was to determine the effect of two irrigation methods, surface and subsurface drip irrigation combined with four irrigation levels, 100, 80, 60 and 40% of crop evapotranspiration on yield and yield components of potato grown on sandy soil. The field experiments were conducted in the years 2008 and 2009. In terms of soil water availability to plants, subsurface drip provided more favorable growth conditions for plant growth and maintained higher soil water content at the root zone, which resulted in a significant higher potato yield compared to surface drip irrigation. The difference between the two irrigation methods on yield components was concentrated on the mean tuber weight per plant, while no significant difference was found on the tuber number per plant. Reducing the amounts of applied water significantly decreased total potato yield and its components. Under subsurface drip irrigation, reducing amounts of applied water to 80% ETc gave comparable yield and yield components to surface drip at full irrigation supply, indicating that 20% irrigation water can be saved without affecting the potato yield. At all irrigation levels, subsurface drip recorded higher water use efficiency (WUE) over surface drip. Maximum value was observed at 40% ETc. Fertilizer use efficiency (FUE) was also higher under subsurface drip and reduced significantly under both irrigation methods with increasing water deficit. These results suggested that subsurface drip offers the potential of better water management with respect to saving and distribution of water in the root zone and to obtain maximum yield accompanied by highest water and FUE.  相似文献   
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The present study was undertaken to investigate the genetic nature of zinc (Zn) accumulation in the ear‐leaves of maize (Zea mays L.) plants. Fourteen inbred lines were evaluated. Out of which, five inbreds were chosen, two high Zn accumulators (Rg‐5 and Rd‐2), two low Zn accumulators (Rg‐8 and G‐307) and a moderate one (K‐64). These five parental inbreds were utilized to obtain all possible ten F1 hybrids (in one direction), 10 F2, 10 Bl, and 10 B2. All genotypes were planted and Zn was estimated at 50% tasseling stage. Zinc accumulation in the present genotypes was found to be genetically controlled and affected by additive genes. Significant values were obtained for the General Combining Abilities (GCA) but not for the Specific Combining Abilities (SCA) and the high Zn accumulating parents were the best general combiners. Four genes were found to be the minimum segregating factors in the (high x low) crosses for Zn accumulation.  相似文献   
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