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731.
An approximately 8-week-old pet Syrian hamster (Mesocricetus auratus) with a 1-week history of dyspnea, hyporexia, and ataxia was submitted for necropsy. On gross examination, the hamster had multiple abdominal adhesions and enlargement of the mesenteric lymph node. Histologic evaluation revealed multicentric lymphoma of the liver, jejunum, mesenteric lymph node, testicular fat pad, and epididymis. Based on the hamster's age and the type and distribution of the lymphoma, a presumptive diagnosis of hamster polyomavirus-induced lymphoma was made. A specific polymerase chain reaction (PCR) was developed, which confirmed the diagnosis. An in situ PCR demonstrated hamster polyomavirus DNA within lymphocytes of the multicentric lymphoma and renal tubular epithelial cells and within clusters of enterocytes in the jejunum. These data are consistent with environmental dissemination of hamster polyomavirus virions through the renal tubular epithelium and into the urine and with fecal shedding of hamster polyomavirus virions; however, additional studies will be needed to confirm these observations.  相似文献   
732.
Diflubenzuron was absorbed and metabolised relatively slowly by the two-spotted spider mite Tetrunychus urticae Koch. Diflubenzuron metabolites, tentatively identified by coincident chromatography with reference standards, included 4- chlorophenylurea, 2, 6-difluorobenzoic acid, 4-chloroformanilide, 2, 6-difluoro-benzamide, and two compounds monohydroxylated in the chloroaniline moiety. There was little absorption of diflubenzuron when applied topically to leaves of bean plants. However, there was translocation of radioactive material when diflubenzuron was injected into the stern. In this case, the radioactivity, which was confined largely to vascular tissue, apparently moved acropetally but exhibited very little or no basipetal movement. Bean plants metabolised injected diflubenzuron, and certain of the metabolites were similar to those isolated from mites.  相似文献   
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734.
Evaluations of biochemical changes associated with spring-style sled dog racing indicate that differences in cortisol, lactate, and serum glucose levels suggest exercise of moderate duration (but high intensity) has metabolic demands that dif-fer from those for typical endurance sled dog racing. Additionally, hematocrit, albumin, sodium, chloride, and blood urea nitrogen levels decreased in one team of dogs, whereas there were mild increases in sodium, chloride, and blood urea nitrogen in the other team. These opposing biochemical findings suggest physiologic changes associated with differences in hydration status, likely attributed to different dietary and hydration strategies used by the respective kennels.  相似文献   
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736.
The objective of these studies was to find alternative Rapid Visco Analyser (RVA) viscoelastic parameters that are predictable by near‐infrared spectroscopy (NIRS). Currently, RVA instruments are widely used in assessing cooking and processing characteristics in rice. The ability to predict RVA parameters by NIRS would be useful in rapidly determining rice pasting qualities, but NIRS does not correlate with the traditional parameters (peak viscosity, final viscosity, breakdown, consistency, and setback). Alternative RVA parameters were sought by collecting RVA and NIRS data for a total of 86 short, medium, and long grain rice cultivars. The amylose contents were 0.41–24.90% (w/w) and protein concentrations were 8.47–11.35% (w/w). Partial least squares (PLS) regression models generated for the entire NIR spectrum against the RVA curve showed viscosity at 212–228 sec (80°C ± 1) varied linearly with NIR spectra (1,100 to ‐2,500 nm). Regression coefficient values were R = 0.961 for 212 sec and R = 0.903 for 228 sec. The PLS correlation coefficient for the prediction of amylose at 212–228 sec decreases along with the NIRS correlation to the same time frame. An opposite trend was observed for the correlation with protein at 212–228 sec. This comparison suggests the importance of amylose and protein in water absorption during this time frame.  相似文献   
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738.
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