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61.
Janelle S. Renschler Gregg A. Dean 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2009,38(1):69-72
Abstract: A 13‐year‐old domestic shorthair cat was presented for evaluation of pollakiuria. Laboratory abnormalities included mild hypercholesterolemia, moderate hypertriglyceridemia, and a mild increase in the Na:K ratio (43, reference interval 32–41). Abdominal ultrasonography revealed urinary calculi and a soft tissue mass between the right caudate liver lobe and the right kidney. Surgery was done to remove the cystic calculi, and aspirates of the mass were obtained. Cytologic specimens contained a population of large, round to angular cells with round nuclei, coarse irregularly stippled chromatin, 1–2 prominent round to angular nucleoli, and abundant pale basophilic cytoplasm distended by numerous well‐delineated vacuoles. Rare binucleated cells and micronuclei, and moderate anisocytosis, anisokaryosis, and anisonucleoleosis were noted. The cytologic interpretation was adrenal neoplasia, consistent with adrenal carcinoma. Approximately 4 months later, the cat developed vomiting, dehydration, weakness, and cervical ventroflexion. Serum biochemical alterations at that time included marked hypokalemia (2.4 mmol/L, reference interval 3.4–5.6 mmol/L) and a markedly increased Na:K ratio (65, reference interval 32–41). Mean systolic blood pressure was 205 mmHg. Surgical removal of the mass was accomplished via right adrenalectomy and a diagnosis of adrenal carcinoma was confirmed histologically. Plasma aldosterone concentration (measured preoperatively) was 1358 pmol/L (reference interval 194–388 pmol/L). Primary hyperaldosteronism caused by a functional adrenal carcinoma is an uncommon condition in cats. 相似文献
62.
Patchouli oil obtained from Pogostemon cablin (Blanco) Benth and its main constituent, patchouli alcohol, were tested for their repellency and toxicity against Formosan subterranean termites (Coptotermes formosanus Shiraki). Both were found to be toxic and repellent. Unusual tissue destruction was noted inside the exoskeleton of the termite after patchouli alcohol was topically applied to the dorsum. 相似文献
63.
Tingey David T. Rodecap Kent D. Lee E. Henry Hogsett William E. Gregg Jillian W. 《Water, air, and soil pollution》2002,139(1-4):325-341
The objective of this study was to determine if theO3sensitivity of Phaseolus vulgaris L. changed withplant development. Plants exposed to charcoal-filtered airor elevated O3 throughout the study were compared tothose exposed only during the vegetative or reproductivestages. Effects of pod development on O3 sensitivitywere also examined by removing flowers from a subset ofplants. We found that plant developmental stage significantly altered O3 sensitivity. Exposures during vegetative stagescaused little foliar injury and had only a small impact on totalgrowth and yield. In contrast, exposures during pod development had a much greater effect on foliar injury, growth and yield. Pod development significantly increased O3 induced foliar injury and O3 impacts on plant growth. We suggest that thegreater O3 sensitivity during pod filling and maturation isthe consequence of reduced energy levels available for homeostatic repair processes. 相似文献
64.
Michael M Garner Carol Shwetz Jan C Ramer James M Rasmussen Kris Petrini Daniel F Cowan James T Raymond Gregory D Bossart Gregg A Levine 《Journal of zoo and wildlife medicine》2002,33(4):350-355
Diffuse hyperplastic goiter was diagnosed by histopathology in 11 perinatal bottlenose dolphins (Tursiops truncatus) that died at four separate zoos and aquaria. Thyroid morphology of these animals was compared with the histologically normal thyroids of two stranded wild bottlenose dolphin calves, a neonate and a 2-mo-old calf. Histologic changes included reduced follicular luminal diameter, markedly reduced or absent luminal colloid, hypertrophy of follicular epithelium, and follicular dysplasia. The etiology of the thyroid gland lesion was not identified. Cause of death was not determined for most of these animals, but they were presumed to have died from metabolic derangements associated with the thyroid lesion, drowning, or dystocia. 相似文献
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This article is motivated by the need of biological and environmental scientists to fit a popular nonlinear model to binary
dose-response data. The four-parameter logistic model, also known as the Hill model, generalizes the usual logistic regression
model to allow the lower and upper response asymptotes to be greater than zero and less than one, respectively. This article
develops an EM algorithm, which is naturally suited for maximum likelihood estimation under the Hill model after conceptualizing
the problem as a mixture of subpopulations in which some subjects respond regardless of dose, some fail to respond regardless
of dose, and some respond with a probability that depends on dose. The EM algorithm leads to a pair of functionally independent
two-parameter optimizations and is easy to program. Not only can this approach be computationally appealing compared to simultaneous
optimization with respect to all four parameters, but it also facilitates estimating covariances, incorporating predictors,
and imposing constraints. This article is motivated by, and the EM algorithm is illustrated with, data from a toxicology study
of the dose effects of selenium on the death rates of flies. Other biological and environmental applications, as well as medical
and agricultural applications, are also described briefly. Computer code for implementing the EM algorithm is available as
supplemental material online. 相似文献
67.
Marland G Obersteiner M Schlamadinger B 《Science (New York, N.Y.)》2007,318(5853):1066-8; author reply 1066-8
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70.
From tides to mixing along the Hawaiian ridge 总被引:2,自引:0,他引:2
Rudnick DL Boyd TJ Brainard RE Carter GS Egbert GD Gregg MC Holloway PE Klymak JM Kunze E Lee CM Levine MD Luther DS Martin JP Merrifield MA Moum JN Nash JD Pinkel R Rainville L Sanford TB 《Science (New York, N.Y.)》2003,301(5631):355-357
The cascade from tides to turbulence has been hypothesized to serve as a major energy pathway for ocean mixing. We investigated this cascade along the Hawaiian Ridge using observations and numerical models. A divergence of internal tidal energy flux observed at the ridge agrees with the predictions of internal tide models. Large internal tidal waves with peak-to-peak amplitudes of up to 300 meters occur on the ridge. Internal-wave energy is enhanced, and turbulent dissipation in the region near the ridge is 10 times larger than open-ocean values. Given these major elements in the tides-to-turbulence cascade, an energy budget approaches closure. 相似文献