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131.
This paper describes the chemical and biochemical properties of exopolysaccharides (EPS) produced by Ophiostoma ulmi and O. novo‐ulmi isolates, the Dutch elm disease (DED) fungi. Some of EPS have been considered as pathogenicity factor in the DED complex. The selected isolates grow well and produce EPS in a medium containing various types of carbon and nitrogen sources. EPS obtained from potato dextrose broth (PDB) medium appeared to be opaque, firm and stained purple blue with iodine‐potassium iodide solution, whereas those from yeast extract (YE) medium were less opaque, jelly‐like and remained unchanged in iodine solution. The selected fungal isolates produced much higher molecular weight EPS from the medium containing YE than from PDB. The results of this study suggest that high molecular weight compounds produced by O. ulmi (W9) and O. novo‐ulmi (R136) are not involved in DED pathogenesis. Spectrometric analysis of acid‐digested EPS obtained from PDB and YE revealed the presence of a monomer similar to glucose used as a standard. Thin layer chromatography indicated that glucan‐1,4‐α‐glucosidase (glucoamylase) only hydrolyses EPS from PDB media and releases glucose. The results strongly indicate that isolates of O. ulmi and O. novo‐ulmi produce starch‐like EPS from PDB medium. The EPS obtained from YE medium lacked this characteristic. The biological significance and the potential use of these EPS are discussed. 相似文献
132.
M.J. Garcia Iglesias J. M. Martinez Rodriguez A. M. Bravo Moraly A. Escudero Diez 《Anatomia, histologia, embryologia》1992,21(4):364-372
An ultrastructural study to the corpus luteum (CL) from 263 non pregnant female cattle slaughtered in slaughter-houses of León (Spain) was done. The luteal cells are classified in five types, noted with roman numbers. We made a comparison between these cells and the cells described in the literature. We believe that luteal cells have a development from type I to V, the first type is the principal inside the developing CL. The types II and III are in the mature CL, and the two last types are in the degenerating CL. It will be the same cell in different stages of development. We did not find characteristic structures to differentiate luteal cells originating from the granulosa or the theca. 相似文献
133.
E. Escolar D. Perez-Alenza M. Diaz A. Rodriguez 《The Journal of small animal practice》1993,34(11):567-570
A case study of renal tubular dysfunction similar to idiopathic Fanconi syndrome is reported in an adult dobermann pinscher. The main clinical and histopathological features of this syndrome are described. 相似文献
134.
135.
In the brains of newborn rats, about half of the tubulin molecules are modified posttranslationally by the addition of an aromatic amino acid at the carboxyl terminus of the alpha chain. Of the added residues, 96 percent are tyrosine and 4 percent are phenylalanine. After induction of hyperphenylalaninemia, the proportion of tubulin molecules containing carboxyl terminal phenylalanine increases up to eightfold and the pool of tyrosine-containing molecules decreases by an equivalent amount. 相似文献
136.
137.
Rodriguez DB Mackin A Easley R Boyle CR Hou W Langston C Walsh AM Province MA McLeod HL 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2004,18(3):339-345
Thiopurine methyltransferase (TPMT) produces inactive metabolites of azathioprine and, in humans, has a variable amount of activity. Humans with low TPMT activity commonly develop myelotoxicity when receiving azathioprine. Our study sought to characterize the distribution of TPMT activity in a population of dogs and to determine whether the pretreatment knowledge of red blood cell (RBC) TPMT activity could predict myelotoxicity in dogs receiving azathioprine. RBC TPMT activity was measured in 299 healthy dogs, and 9 dogs that represented a wide range of enzyme activity received azathioprine at a standard therapeutic dose for 30 days. TPMT activity in healthy dogs was log normally distributed and varied over an approximately 7-fold range. Geometric mean, minimum, and maximum RBC TPMT activities were 37.1, 16.3, and 115 nmol per gram of hemoglobin (gHb) per hour, respectively. TPMT deficiency was not identified. Two populations of TPMT activity in dogs were detected by statistical modeling (commingling analysis). Dogs with intermediate TPMT activity (14-38 nmol/gHb/h) receiving azathioprine had significantly lower neutrophil counts during week 4 than during weeks 0-3, whereas those with high activity (>39 nmol/gHb/h) did not have a significant change in neutrophil count. An analysis of TPMT activity in 6 dogs with a history of azathioprine-associated myelotoxicity in a clinical setting revealed either intermediate or high TPMT enzyme activity in all dogs, suggesting that TPMT activity, as measured in RBCs, is not the sole cause of severe azathioprine-associated myelosuppression in dogs. 相似文献
138.
Dawson WW Jeffery G Dawson JC Kessler MJ Rodriguez J Westergaard GC 《Veterinary ophthalmology》2004,7(6):391-396
There is growing evidence for an interaction among fundus pigmentation, character, geography and the function and structure of the outer retina. We examined three inbred groups of rhesus macaques (132 eyes) including all ages. One was a smaller (18 eyes) group. Coat colors were variations of brown-tan however, the smaller group had lighter 'golden' coats and colors. Fundus images were classified for pigmentation and its geographic distribution. In golden-coated animals there was bias toward nasal fundus hypopigmentation with the optic disk as a watershed demarcation zone, which extended in the superior-inferior direction. Temporal fundus hypopigmentation did not occur in the absence of nasal hypopigmentation. More common, darker coated samples showed a characteristic diffuse fundus pigmentation. There was no evidence for albinism or large variations in macular pigmentation. Rhesus monkeys can exhibit geographically controlled genetic development of fundus pigmentation. Hypopigmentation provides for access to the choroidal infrastructure. 相似文献
139.
140.
J. Rodriguez M.‐C. Blais C. Lapointe J. Arsenault L. Carioto J. Harel 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2014,28(2):284-293