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11.
The trial was aimed at evaluating probable superiority, if any of nano zinc (NZn) over inorganic zinc (Zn) on immunity, serum minerals and T3, T4, and IGF-1 hormone profiles in goats. NZn was synthesized by using 0.45 M aqueous solution of Zn nitrate and 0.9 M aqueous solution of sodium hydroxide (average particle size 74 nm). Twenty-four male goats were grouped into four groups as per their body weight and were supplemented with either a basal diet with concentrate and straw at 50:50 ratio (Negative control, NC) alone or supplemented with 50 mg/kg Zn (Control) from inorganic Zn source, that is ZnO (IZn-50), 50 mg/kg Zn from NZn (NZn-50) or 25 mg/kg Zn from NZn (NZn-25). No change was observed in thyroid hormone status on zero and 90th day of experimental feeding, but NZn supplementation improved (p < 0.05) IGF-1 level on 90th day serum samples. Zn supplementation improved the humoral immunity in all the groups irrespective of the source. Similarly, cell-mediated immunity (CMI) measured by skinfold thickness after injecting Con-A, was also improved in Zn supplemented groups than control at 6, 12 and 48 h of incubation. NZn-50 animals showed highest HI (haemagglutination inhibition) titre as well as skin thickness. The (cluster of differentiation in %) was more (p < 0.05) in Zn supplemented groups. NZn-50 showed higher (p < 0.05) count than NC and similar (p > 0.05) to IZn-50 and NZn-25 groups without affecting (p > 0.05) the ratio of , among the treatment groups. Thus, NZn supplementation at 25 mg/kg had similar immunity and serum T3, T4 and IGF-1 profiles compared with IZn at 50 mg/kg dose.  相似文献   
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The calli induction from different Sunflower necrosis virus (SNV)-infected explants of sunflower was initiated on Murashige & Skoog medium amended with benzyladenine at 1 mg l -1 and indole acetic acid at 0.5 mg l -1. The virus was purified from the induced calli by sucrose density gradient centrifugation and the viral particles were confirmed by transmission electron microscopy. The SNV infection in uninfected calli was established by a soak prick method and the viral development was confirmed by a plant infectivity test. Serological analyses such as Ouchterlony double immnuodiffusion test, enzyme-linked immunosorbent assay and Western blot using anti-SNV antibodies yielded positive reactions with the purified SNV. These investigations have demonstrated that the SNV could be cultured in calli and maintained in vitro in pure form for a long period of time.  相似文献   
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Oils enhance the efficacy of entomopathogens used as augmentative biological control agents. The effect of cheap and commonly available various plant oils,viz., sunflower oil, neem oil, pongamia oil, castor oil, gingili oil, coconut oil, groundnut oil, and the adhesive stickers laboline and Triton-X100, onVerticillium lecanii, an entomopathogen recommended for the control of major sucking pests of horticultural importance, was studied. The first four oils screened, significantly enhanced mycelia growth and conidiation. Gingili oil, coconut oil, groundnut oil and Triton-X100 were found to be poor carriers ofV. lecanii in relation to mycelia growth and conidiation. http://www.phytoparasitica.org posting July 14, 2005.  相似文献   
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The efficiency of enzymatic conversion of glucose into glucose-6-phosphate in fish fed carbohydrates is still a matter of debate. This study reports the first ever identification of hexokinase-family members at a molecular level in fish. The deduced amino acid sequences of six cDNA clones allowed their assignement either to hexokinase IV (glucokinase) for rainbow trout (Oncorhynchus mykiss), common carp (Cyprinus carpio) and gilthead seabream (Sparus aurata) or to hexokinase I/II for the common carp (two clones) and the gilthead seabream, based on their similarities to known members of the HK family. The evolutionary relationships among these sequences were investigated by phylogenetic analysis. These hexokinase sequences constitute potential molecular tools for analysis of interspecific differences in dietary carbohydrate utilization in fish.  相似文献   
15.
Light-matter interactions can be controlled by manipulating the photonic environment. We uncovered an optical topological transition in strongly anisotropic metamaterials that results in a dramatic increase in the photon density of states-an effect that can be used to engineer this interaction. We describe a transition in the topology of the iso-frequency surface from a closed ellipsoid to an open hyperboloid by use of artificially nanostructured metamaterials. We show that this topological transition manifests itself in increased rates of spontaneous emission of emitters positioned near the metamaterial. Altering the topology of the iso-frequency surface by using metamaterials provides a fundamentally new route to manipulating light-matter interactions.  相似文献   
16.
Thirty-six isolates of Fusarium oxysporum originated from Eruca vesicaria and Diplotaxis tenuifolia together with eight reference strains belonging to the formae speciales raphani, matthioli and conglutinans, typical on the Brassicaceae family, were tested for pathogenicity on two species of rocket plants (E. vesicaria L., syn. E. sativa, cv. ‘Rucola coltivata’; and D. tenuifolia cv. ‘Winter’) cultivated in the glasshouse. The results showed that different isolates were slightly, moderately or highly virulent. The strains were examined for differences in the nucleotide sequence of the ribosomal DNA (rDNA) intergenic spacer (IGS) region, about 2.5 kb long. The phylogenetic (neighbor-joining) analysis performed on the isolates enabled identification of four different groups, named I, II, III and IV. Thirty-one isolates out of 36 clustered in group I and were genetically similar to F. oxysporum f.sp. raphani. By considering the pathogenicity of the strains included in Group I, a partial host specialization could be observed: the average disease index of the isolates from D. tenuifolia was higher on wild rocket, whereas the average disease index of the isolates from E. vesicaria was higher on cultivated rocket. Moreover, isolates from cultivated rocket showed, on average, a higher degree of aggressiveness than the isolates from wild rocket. Concerning Group I, the sequence analysis confirmed the homogeneity of the population, with only five parsimony-informative SNPs and five haplotypes. Twenty-six out of 31 isolates belonged to haplotype 1. Groups II and III were genetically similar to strains of F. oxysporum f.sp. matthioli. Three other strains, not pathogenic or with a medium level of virulence, clustered together in Group 4, but their sequence was distant from that of other formae speciales. The pathogenicity and IGS analysis confirmed the presence of virulence variation and genetic diversity among the F. oxysporum isolates studied. To our knowledge, this is the first report of differentiation of formae speciales of F. oxysporum on rocket plants by IGS analysis.  相似文献   
17.
A potentially diagnostic 18S rDNA (ribosomal DNA) gene was amplified reliably from red-listed ethnomedicinal species of Myristica and its wild and related genera. Individuals from nine species of Myristicaceae were utilized for the study. The sequences ranged from 1,767 to 1,794 nucleotide (nt) in length. The GC content (%) varied from 52.77 to 51.04. The frequencies (%) of nt were A (23.31), T (23.82), C (24.48) and G (28.39). The alignment of all sequences produced 195/1,516 variable sites and 1,257/1,516 conserved sites. Total numbers of single nucleotide polymorphism (SNP) sites found in the alignment were 146/1,516. Knema andamanica (Warb.) W.J. de Wilde was the most distinct that included 18 variable regions and 15 InDel with 27 SNP sites, specific to this species. The identified regions from nine species of Myristica and its wild and closely related genera were deposited in the GenBank Database (Accession numbers JN228257-JN228265). Comparison of morphological identifications and phylogenetic analysis indicated that the specimens were correctly assigned on the basis of a short stretch of 18S rDNA (~1,600 bp) making this a potentially useful marker for the rapid molecular assignment of an unknown related species also. Significant sequence homology ranging from 72 to 99 % was observed on comparison with 18S rDNA genes of other plants in the public domain. A comparison of intraspecific data information of nine 18S with that of 73 matK and 86 rbcL sequences from GenBank revealed that polymorphism, divergence and conservation is higher in 18S locus for Myristicaceae. Hence these markers may be utilized for phylogenetic analysis, evaluation of species richness during ecological surveys or for environmental assessments. These molecular markers are especially important due to the fact that the species studied are mostly vulnerable and red-listed with limited availability in endangered ecological niches.  相似文献   
18.
Landscape Ecology - Both plant size and distribution of plants and resources across landscapes are known to influence pollinator behavior and resulting plant reproductive success. However,...  相似文献   
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