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971.
Objective: To determine the effect of storage on ammonia concentration in canine packed red blood cell (pRBC) units.
Design: In vitro and in vivo study.
Setting: University Veterinary Teaching Hospital.
Interventions: Ammonia concentration was measured in 7 units of canine pRBC prepared in citrate-phosphate-dextrose (CPD) and Adsola on Days 1 and 35 of storage. Ammonia was measured in 4 additional units of canine pRBC on Days 0, 7, 14, 21, 28, and 35. Plasma ammonia was also determined in 5 anemic dogs receiving pRBC.
Measurements and Main Results: Ammonia concentration increased from 73 ± 15 mmol/L (mean ± SD) on Day 1 to 800 ± 275 mmpl/L on Day (p<0.001). When measured every 7 days in 4 units of canine pRBC, ammonia concentration increased from 23 ± 8 mmol/L on Day 0 to 179 ± 13 mmol/L (Day 7), 276 ± 56 mmol/L (Day 14). 383 ± 47 mmol/L (Day21), 466 ± 30 mmol/L (Day 28), and 562 ± 27 mmol/L (Day 35) (p<0.05 for all comparisons). In a preliminary study, plasma ammonia concentration measured in blood samples from 5 anemic dogs without primary liver disease immediately before and after transfusion with 5–10 ml/kg of stored pRBC remained in the normal reference range.
Conclusions: The ammonia concentration in stored canine pRBC increased markedly with time. In this preliminary study, ammonia concentrations in dogs without primary liver disease did not increase above the reference range after transfusion with pRBC.  相似文献   
972.
Ovine GM-1 gangliosidosis is an inherited lysosomal storage disease. Nine lambs affected with the disease were studied to characterize clinical signs and to determine if there were any pathognomonic clinicopathologic abnormalities. Evaluation included physical, ophthalmic, and neurologic examinations, complete blood counts, serum enzyme and electrolyte analyses, urinalyses, cerebrospinal fluid analyses, blood gas analyses, roentgenograms, electromyograms, and electrocardiograms. Two affected lambs had clinicopathologic tests performed before and after the onset of clinical signs. The only consistent abnormalities recognized were nonspecific signs referable to the central nervous system; predominantly ataxia, conscious proprioceptive deficit most severe in the hind limbs, blindness, and recumbency. Lambs continued to eat and drink, though at diminished levels and with loss of body condition. It was concluded that there are no pathognomonic clinicopathologic abnormalities associated with ovine GM-1 gangliosidosis, and antemortem diagnosis requires enzyme assay of leukocytes or cultured fibroblasts, or lectin histochemistry of tissues obtained by biopsy. Lysosomal storage diseases should be considered among the differential diagnoses in young animals presenting with early neonatal death or with nonspecific neurological signs, in concert with an absence of diagnostic clinicopathologic findings.  相似文献   
973.
An 8-year-old male Labrador retriever presented with a rear limb lameness cased by an osteolytic lesion of the left acetabulum and femoral head and neck. Initial bone biopsy study was nondiagnostic. Histopathologic study and culture of the subsequently excised femoral head and neck revealed a Staphyloccocus intermedial arthritis and osteomyelitis. Neoplash was ruled out on the basis of histopathologic analysis.  相似文献   
974.
975.
Laboratory studies of the cotoxicity of a pyrethroid insecticide, fenvalerate, and several organophosphorus insecticides against the two-spotted spider mite, Tetranychus urticae Koch, showed that a useful degree of potientation of toxicity occurred. The most effective combination of fenvalerate and azinphos-methyl was found to be a 1:1 ratio. Phosphates and phosphorodithioates in combination with fenvalerate were more toxic than phosphoromonothioates. The results suggest a practical method of improving the acaricidal activity of pyrethroid insecticides.  相似文献   
976.
Preparation of 3-phenoxybenzyl chrysanthemates and their dihalovinyl analogues substituted with a cyano group at the 2-, 6-, (R)-α-, or (S)-α- positions is described. The (R)- and (S)- isomers of α-cyano-3-phenoxybenzyl esters of 2,2-difluoro-, -dichloro-, and -dibromo-vinyl analogues of cis- and trans- chrysanthemic acid are separated chromatographically, as are the separate pairs of enantiomers of fenvalerate, (RS)-α- cyano-3-phenoxybenzyl (RS)-2-(4-chlorophenyl)-3-methylbutyrate. An optically active ester of α-cyano-3-phenoxybenzyl alcohol (obtained using D -oxynitrilase) with 2,2,3,3-tetramethylcyclopropanecarboxylic acid is synthesised.  相似文献   
977.
The build-up and decline of quintozene and hexachlorobenzene residues in protected lettuce, resulting from one to five treatments of the soil (each of 35 g m-2) with a quintozene formulation, have been studied. Residue levels were monitored in each experimental crop during growth until harvest. Residues in the soil at harvest were also determined. Quintozene residues in the harvested lettuce were in the range < 0.02–0.80 mg kg?1 and those of hexachlorobenzene were in the range < 0.02–0.05 mg kg?1 (expressed on a fresh weight basis). Residue levels in the soil were 5.4–231 mg kg?1 for quintozene, and 0.20–5.4 mg kg?1 for hexachlorobenzene (expressed on a dry weight basis). Under the experimental conditions of the trial there was no significant build-up of quintozene or hexachlorobenzene in harvested lettuce, even after five treatments to the same site.  相似文献   
978.
Clover is frequently grown in rotation with cereals in order to increase soil nitrogen. The systemic fungicide triadimefon, widely used against cereal pathogens, is readily taken up from soil by clover and degraded to a single major metabolite. Plant weight and symbiotic nitrogen fixation by Rhizobium trijolii are affected only by concentrations of triadimefon in soil that are much in excess of those likely to be encountered in practice. Triadimefon residues are thus unlikely to affect nitrogen fixation by clover under field conditions.  相似文献   
979.
The sorption of pesticides to soil particles has implications for their distribution and fate in the soil environment. A batch equilibrium technique was used to investigate sorption of the fungicide AEC623892 to intact and hydrogen-peroxide-treated whole soils and several particle-size fractions isolated from them. Sorption of AEC623892 to the soil as a whole was low. K(f oc) values measured in the whole soils were 169.2 and 41.9 ml g(-1) for Soil A and Soil B respectively. The highest values of K(f oc) were measured in soil particle-size fractions <53 microm (266.5 ml g(-1) in the 2-20 microm fraction of Soil A; 471.9 ml g(-1) in the 20-53 microm fraction of Soil B). Sorption was most irreversible in the 2-20 microm fractions. Overall, treatment of soil particle-size fractions with hydrogen peroxide resulted in lower values of K(f oc) (112.3 ml g(-1) in Soil A whole soil and 30.9 ml g(-1) in Soil B whole soil). In both soils, the maximum sorption among hydrogen-peroxide-treated samples was observed in the <2 microm fraction (166.6 and 311.0 ml g(-1) for Soil A and Soil B, respectively). Investigation of the mineralogical composition of the soils suggested that the clay mineralogy (dominated by kaolinite and illite) is less likely to account for the differences in sorption observed than differences in the characteristics of the soil organic matter. Thermal analysis of the different soil fractions indicated that hydrogen peroxide treatment preferentially removed aliphatic fractions of organic matter, but had less effect on lignin-like, aromatic fractions.  相似文献   
980.
Non-specific factors may affect the vitality or integrity of the skin, increase its intrinsic reactivity, or aggravate, or promote, other skin disease. External factors such as temperature, humidity, irritant agents and external débris, and internal factors such as diet, psychogenic, neurogenic, hormonal and metabolic abnormalities, may have a profound effect on both the abnormal and normal canine integument.
Résumé. Les facteurs non spécifiques peuvent affecter la vitalité et l'intégrité de la peau, augmenter sa réactivité intrinsèque et soit aggraver, soit favoriser d'autres affections cutanées. Les facteurs externes tels que la température, l'humidité, les agents irritants, les débris externes, ainsi que les facteurs internes comme le régime, les anomalies psychogènes, neurogènes, hormonales, métaboliques peuvent exercer un effet profond sur le tégument du chien normal ou pathologique.
Zusammenfassung. Nichtspezifische Faktoren können die Vitalität oder Integrität der Haut beeinflussen, ihre innere Reaktivität erhöhen oder andere Hautkrankheiten verschlimmern oder fördern. Äussere Faktoren wie Temperatur, Feuchtigkeit, Reizstoffe und äussere Fremdkörper und innere Faktoren wie die Ernährung und psychogene, neurogene, hormonale und Stoffwechselanomalien können einen nachhaltigen Einfluss sowohl auf die anomale als auch die normale Haut des Hundes haben.  相似文献   
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