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排序方式: 共有750条查询结果,搜索用时 15 毫秒
1.
Eiko E. Kuramae Alexandre L. Buzeto Maisa B. Ciampi Nilton L. Souza 《European journal of plant pathology / European Foundation for Plant Pathology》2003,109(4):391-395
Fungi isolated in Brazil, from lettuce, broccoli, spinach, melon and tomato, were identified as Rhizoctonia solani. All lettuce isolates anastomosed with both AG 1-IA and IB subgroups and all isolates from broccoli, spinach, melon and tomato anastomosed with AG 4 subgroup HG-I, as well as with subgroups HG-II and HG-III. DNA sequence analyses of ribosomal internal transcribed spacers showed that isolates from lettuce were AG 1-IB, isolates from tomato and melon were AG 4 HG-I, and isolates from broccoli and spinach were AG 4 HG-III. The tomato isolates caused stem rot symptoms, the spinach, broccoli and melon isolates caused hypocotyl and root rot symptoms on the respective host plants and the lettuce isolates caused bottom rot. This is the first report on the occurrence in Brazil of R. solani AG 4 HG-I in tomato and melon, of AG 4 HG-III in broccoli and spinach and of AG 1-IB in lettuce. 相似文献
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Paixão Sonália Ferreira Fritzen Juliana Torres Tomazi Crespo Sarah Elizabeth Izzo de Moraes Pereira Helder Alfieri Alice Fernandes Alfieri Amauri Alcindo 《Tropical animal health and production》2018,50(8):1947-1950
Tropical Animal Health and Production - Serological studies have characterized the presence of the bovine viral diarrhea virus (BVDV) infection in water buffalo herds worldwide. However, the... 相似文献
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Jeann Leal de Araújo Alice C. A. M. Arruda Nayadjala T. A. Santos Glenison F. Dias Thiago F. L. Nery Fabio Del Piero Richard Ploeg Brian F. Porter Ingeborg M. Langohr 《Journal of veterinary diagnostic investigation》2021,33(3):600
A 4-mo-old northern red-shouldered macaw (Diopsittaca nobilis) was admitted to the veterinary hospital of the Arruda Câmara Zoo, in the State of Paraiba, Brazil, for investigation of an orbital mass. Given rapid progression and lack of response to treatment, the bird was euthanized, and an autopsy was performed. Histologically, the mass consisted of a retrobulbar invasive tumor characterized by tubular and rosette-like structures, with interspersed heteroplastic tissues, such as aggregates of neuroglial cells and islands of hyaline cartilage. The tumor was immunopositive for pancytokeratin, GFAP, NSE, and S100. These findings were compatible with an ocular teratoid medulloepithelioma, a neoplasm best described in humans but also reported rarely in young cockatiels and African Grey parrots. 相似文献
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Ida T Miyazato M Naganobu K Nakahara K Sato M Lin XZ Kaiya H Doi K Noda S Kubo A Murakami N Kangawa K 《Domestic animal endocrinology》2007,32(2):93-105
Ghrelin, a novel 28-amino acid peptide with an n-octanoyl modification at Ser3, has been isolated from rat and human stomach as an endogenous ligand for the growth hormone secretagogue receptor. Here, we purified feline ghrelin and examined its possible physiological role in cats. The major active form of feline ghrelin is a 28-amino acid peptide octanoylated (C8:0) at Ser3; except for one amino acid residue replacement, this structure is identical to those of rat and human ghrelins. However, much structural divergence in peptide length and fatty acid modification was observed in feline ghrelin: peptides consisting of 27 or 26 amino acids lacking Gln14 and/or Arg28 were found, and the third serine residue was modified by octanoic acid (C8:0), decanoic acid (10:0), or unsaturated fatty acids (C8:1, C10:1 and C10:2). In agreement with the structural divergence, two kinds of cDNA with different lengths were isolated. Administration of synthetic rat ghrelin increased plasma growth hormone levels in cats, with a potency similar to that in rat or human. Plasma levels of ghrelin in cats increased approximately 2.5-fold after fasting. The present study indicates the existence of structural divergence in feline ghrelin and suggests that, as in other animals, ghrelin may play important roles in GH release and feeding in cats. 相似文献
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Ohba T Shibahara T Kobayashi H Kubo M Takashima A Imai S Murakami S Kadota K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(4):449-453
A 6-month-old barrow presented with lethargy, inappetence and dysstasia. At necropsy, multiple coalescing hemorrhagic foci were detected in the margins of the spleen. Gram-positive bacilli were isolated from the spleen, kidney, muscle and liver. Comparative 16S rDNA gene sequencing analysis of the isolates (TO16177) revealed that they would be the same species of unpublished Arcanobacterium species strain HJ57-14E (accession no. gi 18873551) (99.7% similarity based on a comparison of 675 bp). Histologic examination of the splenic tissue sections revealed extensive necrosis and inflammation, and gram-positive bacilli were discernible. Multifocal necrosis was also detected in the liver. Immunohistochemically, the isolates were cross-reacted with polyclonal antibodies against Arcanobacterium pyogenes and Actinomyces naeslundii, and the reaction was strong for the latter. Similar reactions were found in the suppurative lesions of the tonsil, and occasionally in the spleen and lymph nodes. The present results indicate that the unpublished Arcanobacterium species induced multiple organ failure accompanied by acute hemorrhagic necrotizing splenitis in this growing-finishing pig. 相似文献
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Hiroharu Murakami Seiya Tsushima Takayuki Akimoto Yukiko Kuroyanagi Yoshihiro Shishido 《Soil Science and Plant Nutrition》2013,59(8):1307-1311
The effect of the plowing of clubbed roots of cracifers on the population of Plasmodiophora brassicae in soil was quantitatively studied by measuring the number of resting spores produced in the diseased plants. Though the mean number of resting spores per diseased plant increased with the increase of the disease severity, it remained almost identical for the disease severity classified into category 3 among host species and cultivars tested. Mean number of resting spores per diseased plant ranged from 9.3 to 10.9 (log) regardless of the value of the disease index. When the number of resting spores in soil was calculated based on these data and plant cultivation methods, the values were equivalent to 4.8-6.4 resting spores g-1soil (log)where clubroot disease occurred severely. The value of the disease index of Chinese cabbage plants grown in the pots where clubbed roots of initially grown plants had been plowed into soil (plowing plot) was higher than that in the pots where no plants had been grown (control plot) and where the clubbed roots of initial plants had been removed (removal plot). Though the number of resting spores of P. brassicae in soil decreased by 14% of the inocoKum concentration immediately after the inoculation, the number of spores after the first cultivation in the removal plot was similar to that in the control plot. On the other hand, the number of resting spores in the plowing plot increased significantly compared with that in the control plot. The plowing of clubbed roots into soil resulted in the increase of the population of P. brassicae and disease severity of clubroot in subsequent cultivation in the field. The results corresponded to the values estimated based on the number of resting spores in soil in relation to each value of the disease index. 相似文献
10.
Weber HA Zart MK Hodges AE Molloy HM O'Brien BM Moody LA Clark AP Harris RK Overstreet JD Smith CS 《Journal of agricultural and food chemistry》2003,51(25):7352-7358
The characterization of herbal materials is a significant challenge to analytical chemists. Goldenseal (Hydrastis canadensis L.), which has been chosen for toxicity evaluation by NIEHS, is among the top 15 herbal supplements currently on the market and contains a complex mixture of indigenous components ranging from carbohydrates and amino acids to isoquinoline alkaloids. One key component of herbal supplement production is botanical authentication, which is also recommended prior to initiation of efficacy or toxicological studies. To evaluate material available to consumers, goldenseal root powder was obtained from three commercial suppliers and a strategy was developed for characterization and comparison that included Soxhlet extraction, HPLC, GC-MS, and LC-MS analyses. HPLC was used to determine the weight percentages of the goldenseal alkaloids berberine, hydrastine, and canadine in the various extract residues. Palmatine, an isoquinoline alkaloid native to Coptis spp. and other common goldenseal adulterants, was also quantitated using HPLC. GC-MS was used to identify non-alkaloid constituents in goldenseal root powder, whereas LC-MS was used to identify alkaloid components. After review of the characterization data, it was determined that alkaloid content was the best biomarker for goldenseal. A 20-min ambient extraction method for the determination of alkaloid content was also developed and used to analyze the commercial material. All three lots of purchased material contained goldenseal alkaloids hydrastinine, berberastine, tetrahydroberberastine, canadaline, berberine, hydrastine, and canadine. Material from a single supplier also contained palmatine, coptisine, and jatrorrhizine, thus indicating that the material was not pure goldenseal. Comparative data for three commercial sources of goldenseal root powder are presented. 相似文献