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91.
Biological and Molecular Characterization of a New Carlavirus Isolated from an Aconitum sp 总被引:1,自引:0,他引:1
ABSTRACT A new virus was isolated from symptomless Aconitum napellus plants. The virus, for which the name Aconitum latent virus (AcLV) is proposed, has flexuous particles 640 nm in length. The experimental host range was limited to Nicotiana clevelandii. Electron microscopy studies of ultrathin sections of infected A. napellus tissues revealed the presence of elongated virus particles. No inclusion bodies characteristic of potyvirus infection were observed. AcLV was purified from naturally infected A. napellus by cesium chloride step gradient centrifugation. In sodium dodecyl sulfate-polyacrylamide gel electrophoresis of dissociated purified virus preparations, a major protein component with a molecular mass of 35 kDa was observed. Diagnostic antibodies that could specifically bind to virus particles were produced. The 5' terminus (620 nucleotides) of the viral RNA was cloned and sequenced. It comprised 71 nucleotides from the untranslated 5' terminus and 549 nucleotides of an open reading frame encoding 183 amino acids. Comparison of the predicted amino acid sequence with those of other plant viruses revealed 40 to 60% identity with several carlaviruses. Based on particle morphology, absence of inclusion bodies in ultrathin sections, the relative molecular weight of the coat protein, the nucleotide sequence, and predicted amino acid homology, it is suggested that this virus belongs to the carlavirus group. 相似文献
92.
Rao GS Ramesh S Ahmad AH Tripathi HC Sharma LD Malik JK 《Journal of veterinary pharmacology and therapeutics》2000,23(6):365-372
Pharmacokinetics of enrofloxacin and its active metabolite ciprofloxacin were investigated in normal, febrile and probenecid‐treated adult goats after single intravenous (i.v.) administration of enrofloxacin (5 mg/kg). Pharmacokinetic evaluation of the plasma concentration–time data of enrofloxacin and ciprofloxacin was performed using two‐ and one‐compartment open models, respectively. Plasma enrofloxacin concentrations were significantly higher in febrile (0.75–7 h) and probenecid‐treated (5–7 h) goats than in normal goats. The sum of enrofloxacin and ciprofloxacin concentrations in plasma ≥0.1 μg/mL was maintained up to 7 and 8 h in normal and febrile or probenecid‐treated goats, respectively. The t1/2β, AUC, MRT and ClB of enrofloxacin in normal animals were determined to be 1.14 h, 6.71 μg.h/mL, 1.5 h and 807 mL/h/kg, respectively. The fraction of enrofloxacin metabolized to ciprofloxacin was 28.8%. The Cmax., t1/2β, AUC and MRT of ciprofloxacin in normal goats were 0.45 μg/mL, 1.79 h, 1.84 μg.h/mL and 3.34 h, respectively. As compared with normal goats, the values of t1/2β (1.83 h), AUC (11.68 μg ? h/mL) and MRT (2.13 h) of enrofloxacin were significantly higher, whereas its ClB (430 mL/h/kg) and metabolite conversion to ciprofloxacin (8.5%) were lower in febrile goats. The Cmax. (0.18 μg/mL) and AUC (0.99 μg.h/mL) of ciprofloxacin were significantly decreased, whereas its t1/2β (2.75 h) and MRT (4.58 h) were prolonged in febrile than in normal goats. Concomitant administration of probenecid (40 mg/kg, i.v.) with enrofloxacin did not significantly alter any of the pharmacokinetic variables of either enrofloxacin or ciprofloxacin in goats. 相似文献
93.
Cows' urine was analysed by gas chromatography–mass spectrometry (GC-MS). The profiles from preovulatory, ovulatory and postovulatory samples were compared to establish any qualitative and quantitative differences that might have potential value in olfactory communication. Dichloromethane was used as the solvent for extraction of the compounds. Seven different compounds were detected, of which only two were common to all the chromatograms. The chemical profile of oestrous urine was distinguished by the presence of two specific compounds, viz. di-n-propyl phthalate and 1-iodoundecane, that were not found in the other samples. As oestrous urine has been shown to elicit sexual behaviour in cattle, these two characteristic peaks may represent important chemical compounds that elicit signals that allow the bull to detect `oestrous odours'. 相似文献
94.
Uttarani Maibam Sohan Vir Singh Anil Kumar Singh Suresh Kumar Ramesh Chandra Upadhyay 《Tropical animal health and production》2014,46(7):1155-1160
To evaluate difference in the expression of skin color genes (melanocortin 1 receptor (MC1R) and premelanosome (PMEL)) in lymphocytes during winter and summer season and their correlation with tyrosinase enzyme and cortisol, ten Karan-Fries heifers were selected from National Dairy Research Institute (NDRI) cattle farm. Blood samples were collected from the animals during winter (THI?=?60) and summer (THI?=?83) season at weekly intervals. Relative MC1R and PMEL messenger RNA (mRNA) expression of Karan Fries cattle was found to be significantly (P?0.01) higher during winter than summer. Similarly, tyrosinase activity during winter was found to be significantly (P?0.01) higher than summer season. However, plasma cortisol level was significantly (P?0.01) higher during summer than winter. Thus, expression of the skin color genes showed positive correlation with tyrosinase enzyme, but negative correlation with cortisol level. Expression of MC1R and PMEL in lymphocytes and tyrosinase activity of Karan Fries cattle was highly reduced during summer. The present study showed that the ability of Karan Fries cattle to protect themselves from the harmful radiation of sunlight by melanization decreased with increased heat stress on them. 相似文献
95.
Ericson LM Fan H Peng H Davis VA Zhou W Sulpizio J Wang Y Booker R Vavro J Guthy C Parra-Vasquez AN Kim MJ Ramesh S Saini RK Kittrell C Lavin G Schmidt H Adams WW Billups WE Pasquali M Hwang WF Hauge RH Fischer JE Smalley RE 《Science (New York, N.Y.)》2004,305(5689):1447-1450
Well-aligned macroscopic fibers composed solely of single-walled carbon nanotubes (SWNTs) were produced by conventional spinning. Fuming sulfuric acid charges SWNTs and promotes their ordering into an aligned phase of individual mobile SWNTs surrounded by acid anions. This ordered dispersion was extruded via solution spinning into continuous lengths of macroscopic neat SWNT fibers. Such fibers possess interesting structural composition and physical properties. 相似文献
96.
Jin S Tiefel TH McCormack M Fastnacht RA Ramesh R Chen LH 《Science (New York, N.Y.)》1994,264(5157):413-415
A negative isotropic magnetoresistance effect more than three orders of magnitude larger than the typical giant magnetoresistance of some superlattice films has been observed in thin oxide films of perovskite-like La(0.67)Ca(0.33)MnOx. Epitaxial films that are grown on LaAIO(3) substrates by laser ablation and suitably heat treated exhibit magnetoresistance values as high as 127,000 percent near 77 kelvin and approximately 1300 percent near room temperature. Such a phenomenon could be useful for various magnetic and electric device applications if the observed effects of material processing are optimized. Possible mechanisms for the observed effect are discussed. 相似文献
97.
Aggarwal S Monga AP Perusse SR Ramesh R Ballarotto V Williams ED Chalamala BR Wei Y Reuss RH 《Science (New York, N.Y.)》2000,287(5461):2235-2237
We report the spontaneous formation of uniformly distributed arrays of "tips" (tall conical hillocks) upon oxidation of palladium (Pd) thin films. The formation of the palladium oxide tips depended on the thickness and granularity of the Pd film and on annealing and oxidation conditions. As the Pd film thickness increased from 40 to 200 nanometers, the average height of the tips increased from 0.5 to 1.2 micrometers, their height distribution became broader, and their density decreased from 55 x 10(6) to 12 x 10(6) per square centimeter. Enhanced photoelectron emission from locations corresponding to the tips suggests their possible use in field emission applications. 相似文献
98.
There are two cytoplasmic male sterility (CMS)‐systems in chives (Allium schoenoprasum L.), which can be employed in hybrid breeding. However, the probability for selection of maintainer genotypes from German open pollinated varieties is not known. Therefore, the allelic frequencies of the restorer genes X and T involved in CMS1 were determined in 12 German commercial chive varieties by test crossing single plants to male sterile, temperature‐insensitive genotypes [(S1)xxT] for segregation analyses of offspring. Temperature sensitive genotypes [(S1)xxT_] are able to produce pollen at higher temperatures, and should therefore be excluded from hybrid breeding to avoid self‐pollination of the maternal parent. The mean value of the frequency of the non‐restoring allele x in the populations examined was 0.62. The mean value of the allele t, which is responsible for the temperature insensitivity, was 0.9. As a consequence of these allelic frequencies about one‐third of all plants of the chive varieties examined were designated CMS1 maintainer genotypes, leading to the production of temperature insensitive male sterile lines. The incidence of CMS2 maintainers in the German varieties examined was nearly four times lower than CMS1 maintainers. The mean value of the frequency of the non‐restoring allele st2 involved in the CMS2‐system was 0.29. 相似文献
99.
C. Channuntapipat M. Wirthensohn S.A. Ramesh I. Batlle P. Arús M. Sedgley G. Collins 《Plant Breeding》2003,122(2):164-168
Identification of the incompatibility genotypes of almond cultivars is important in breeding programmes for designing crosses and for selecting progeny. This paper describes a novel molecular technique for the identification of S‐alleles in almond based on the use of PCR primers designed from the sequences of the introns without the need for restriction enzyme digestion. Nine specific pairs of primers have been designed for the S1, S2, S5, S7, S8, S9, S10 (putative), S23 and Sf alleles, and these confirmed the S‐allele specificities for 22 of the 23 accessions for which published information is available. This technique provides a precise method for identifying S‐alleles from the genomic DNAs of almond cultivars, and will be useful for confirming the segregation of alleles in breeding progeny. 相似文献
100.
Revadi Santosh V. Giannuzzi Vito Antonio Vetukuri Ramesh R. Walker William B. Becher Paul G. 《Journal of pest science》2021,94(4):1105-1118
Journal of Pest Science - Larval frass in herbivorous lepidopterans is mainly composed of plant-derived material and microbes from the gut. Despite the fact that frass from conspecific larvae... 相似文献