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51.
Harvey RJ Depner UB Wässle H Ahmadi S Heindl C Reinold H Smart TG Harvey K Schütz B Abo-Salem OM Zimmer A Poisbeau P Welzl H Wolfer DP Betz H Zeilhofer HU Müller U 《Science (New York, N.Y.)》2004,304(5672):884-887
Prostaglandin E2 (PGE2) is a crucial mediator of inflammatory pain sensitization. Here, we demonstrate that inhibition of a specific glycine receptor subtype (GlyR alpha3) by PGE2-induced receptor phosphorylation underlies central inflammatory pain sensitization. We show that GlyR alpha3 is distinctly expressed in superficial layers of the spinal cord dorsal horn. Mice deficient in GlyR alpha3 not only lack the inhibition of glycinergic neurotransmission by PGE2 seen in wild-type mice but also show a reduction in pain sensitization induced by spinal PGE2 injection or peripheral inflammation. Thus, GlyR alpha3 may provide a previously unrecognized molecular target in pain therapy. 相似文献
52.
53.
Tatiana Rakotoson Julie Dusserre Philippe Letourmy Julien Frouin Isabelle Ramonta Ratsimiala Noronirina Victorine Rakotoarisoa Tuong-Vi cao Kirsten Vom Brocke Alain Ramanantsoanirina Nourollah Ahmadi Louis-Marie Raboin 《水稻科学》2021,28(4):379-390
Genome-wide association study (GWAS) was performed for 16 agronomic traits including nitrogen use efficiency (NUE) and yield-related components using a panel of 190 mainly japonica rice varieties and a set of 38 390 single nucleotide polymorphism (SNP) markers. This panel was evaluated under rainfed upland conditions in Madagascar in two consecutive cropping seasons with two contrasted nitrogen input levels. Using another set of five grain traits, we identified previously known genes (GW5, GS3, Awn1 and Glabrous1), thus validating the pertinence and accuracy of our datasets for GWAS. A total of 369 significant associations were detected between SNPs and agronomic traits, gathered into 46 distinct haplotype groups and 28 isolated markers. Few association signals were identified for the complex quantitative trait NUE, however, larger number of quantitative trait loci (QTLs) were detected for its component traits, with 10 and 2 association signals for nitrogen utilization efficiency and nitrogen uptake efficiency, respectively. Several detected association signals co-localized with genes involved in nitrogen transport or nitrogen remobilization within 100 kb. The present study thus confirmed the potential of GWAS to identify candidate genes and new loci associated with agronomic traits. However, because of the quantitative and complex nature of NUE-related traits, GWAS might have not captured a large number of QTLs with limited effects. 相似文献
54.
A new empirical-based scaling method is introduced to predict saturated hydraulic conductivity (K s ) of compacted soils. This method is an improvement of the former non-similar media concept (NSMC) model that is generalized for tilled and untilled conditions. In this method, geometric mean particle size diameter (dg ), geometric standard deviation (σ g ) and saturated soil water content (total porosity) are successfully incorporated in the empirical-based scaling factor of K s . Results showed that the scaled model overestimated K s by ~18%, whereas the NSMC model underestimated K s by ~21%. However, the scaled model based on the similar media concept (SMC) failed to predict K s . Because of the complexity and high uncertainty in determining the shape factor parameter in the NSMC model, it is suggested that the new scaled model might be used reliably in practical cases to predict K s in the various layers of compacted soils irrespective of the tillage condition. Further assessment of the new scaling model in other areas, in which new collected data are available, is recommended. 相似文献
55.
Javad Keshavarz Zarjani Nasser Aliasgharzad Shahin Oustan Mostafa Emadi Ali Ahmadi 《Archives of Agronomy and Soil Science》2013,59(12):1713-1723
The ability of a few soil bacteria to transform unavailable forms of potassium (K) to an available form is an important feature in plant growth-promoting bacteria for increasing plant yields of high-K-demand crops. In this research, isolation, screening, and characterization of six isolates of K solubilizing bacteria (KSB) from some Iranian soils were carried out. The ability of all isolates were tested in three treatments including acid-leached soil, biotite, and muscovite by analyzing the soluble K content after 5 days of incubation at 28 ± 2°C. Identification and phylogenetic analyses were also carried out by morphological, biochemical, and 16S rDNA analyses. Among the six efficient isolates, five isolates belonged to Bacillus megaterium (JK3, JK4, JK5, JK6, and JK7), while isolate JK2 belonged to Arthrobacter sp. The soluble K contents in all isolated-treatments were significantly (p < 0.01) higher than the contents in nonbacteria treatment. Herein, isolate JK2 had lower potential for K solubilization (910 mg kg?1) compared with other isolates in acid-leached soils. The six bacterial strains showed higher solubilized K in biotite treatment than other two treatments. Overall, it can be concluded that the isolates belong to B. megaterium are the most efficient KSB under in vitro condition. 相似文献
56.
Mohammad Valipour Mirkhalegh Ziatabar Ahmadi Mahmoud Raeini-Sarjaz Mohammad Ali Gholami Sefidkouhi Ali Shahnazari Ramin Fazlola 《Archives of Agronomy and Soil Science》2013,59(5):657-678
The present paper aims to estimate the areas equipped for irrigation and desirability of agricultural water management in the world. For this purpose, all necessary information was gathered from Food and Agriculture Organization and checked using World Bank Group. The selected 18 indices were analysed for all 26 regions in the area studied, and the extent of area equipped for irrigation to cultivated area was estimated by 2 different formulas and other 9 indices. In addition, an average index was calculated using various methods to assess region conditions for agricultural water management. The results show that Central Asia is the best region for agricultural water management and the value of relative error is less than 20%. The capability of irrigation and drainage systems was studied using other eight indices with more limited information. The results indicated that trial-and-error policies should be avoided and expert comments be applied to irrigation systems for any crop. 相似文献
57.
Shape-Controlled Synthesis of Colloidal Platinum Nanoparticles 总被引:1,自引:0,他引:1
TS Ahmadi ZL Wang TC Green A Henglein MA El-Sayed 《Science (New York, N.Y.)》1996,272(5270):1924-1926
The shapes and sizes of platinum nanoparticles were controlled by changes in the ratio of the concentration of the capping polymer material to the concentration of the platinum cations used in the reductive synthesis of colloidal particles in solution at room temperature. Tetrahedral, cubic, irregular-prismatic, icosahedral, and cubo-octahedral particle shapes were observed, whose distribution was dependent on the concentration ratio of the capping polymer material to the platinum cation. Controlling the shape of platinum nanoparticles is potentially important in the field of catalysis. 相似文献
58.
Journal of Plant Diseases and Protection - The predatory flower bug Orius similis Zheng (Heteroptera, Anthocoridae) which originated in China is a polyphagous predator that feeds on a wide range of... 相似文献
59.
Ahmad Oryan Nasrollah Ahmadi Mostafa Akhlaghi Arsalan Hosseini 《Aquaculture International》2012,20(4):725-734
To confirm the diagnosis of the infectious pancreatic necrosis, the pancreas, liver, kidney and spleen specimens from 140 rainbow trout (Oncorhynchus mykiss) of weight ranges from 15 to 250?g were processed for routine histopathological and immunohistochemical (IHC) studies together with a nested-PCR using primers that amplify a 164-bp product. Of the 140 fish samples, 37 (26.4%) had a final diagnosis of IPN on the basis of hematoxylin and eosin staining (H&E), while 39/45 (86.6%) were positive by IHC method. With the nested-PCR, 59/140 (42.1%) fish samples were positive. The IHC and nested-PCR showed higher prevalence than histopathology (P?<?0.05). Based on the nested-PCR, as the fish weight increased, IPN positive results decreased (P?<?0.05). However, IHC method detected IPNV constantly in these weight ranges. Only IPNV serotype Sp was identified by nucleotide sequencing and immunohistochemistry, and antiserum to IPNV serotype Ab and IHNV showed negative results in IHC. This is the first comparative diagnostic study of IPN at different weight ranges in cultured salmonids. 相似文献
60.
Integrated use of GIS,remote sensing and multi-criteria decision analysis to assess ecological land suitability in multi-functional forestry 总被引:1,自引:0,他引:1
The Zagros forests are a treasure of valuable oak forests, but they have been severely degraded from long-term misuse. Geographic information systems (GIS) and multi-criteria decision analysis (MCDA) have been increasingly used to improve the management of vulnerable ecosystems to prevent further degradation and increase the sustainability of land use. This study presents a methodology to assess land suitability using remote sensing (RS) to obtain wall-to-wall data for the calculations, GIS to analyze the data, and MCDA to rank alternative land uses. The criteria and subcriteria affecting the suitability of land for different uses were identified and weighted using an analytic hierarchy process. Variables used as subcriteria were assessed using satellite data and other sources of information such as existing maps and field surveys. Numerical values for the subcriteria were classified, and each class was given a priority rating according to expert judgments. Based on the ratings and weights of the subcriteria, a priority map was created for each land use using the weighted linear combination method. The priority maps for different land uses were overlaid to obtain a preliminary land use map, which often indicated several simultaneous land uses for the same location. The preliminary map was further edited by removing unrealistic, mutually exclusive land-use combinations. The study tested and demonstrated the potential of integrating RS, GIS and MCDA techniques for solving complicated land allocation problems in forested regions using a scientifically sound and practical approach for efficient and sustainable allocation of forestland for different uses. 相似文献