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11.
The NeuroScope, a specific and sensitive indicator of cardiac vagal tone, was used to look for differences in autonomic tone between 25 dogs with naturally occurring diabetes mellitus and 23 healthy control dogs, to determine whether there was any correlation between the dogs' cardiac vagal tone, the duration of diabetes and the adequacy of glycaemic control. The cardiac index of parasympathetic activity (cipa) was determined for each dog over a period of 2600 heartbeats. The mean, median and modal cipa values were significantly lower in the diabetic dogs than in the healthy dogs. There was no significant relationship between the cipa values and the duration of disease or the adequacy of recent glycaemic control in the diabetic dogs, but there was a significant inverse relationship between the cipa values and the bodyweight of the diabetic dogs that was not evident in the normal dogs. The conclusions were based on a 500-heartbeat interval selected from the 2600 heartbeats recorded.  相似文献   
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When Tribolium confusum pupae were exposed continuously to temperatures from 10 degrees C to 40 degrees C, the adults which finally emerged exhibited wing abnormalities typical of those obtained with x-irradiation. The data indicate the implication of two processes. Two mathematical models are suggested to account for this phenomenon.  相似文献   
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Topical application of 25, 50, or 100 micrograms of 10,11-epoxy-farnesenic acid methyl ester in peanut oil induced male Ips confusus to produce sex pheromone in the hindgut Malpighian tubule region. Twenty-four hours aftertreatment of male beetles with 100 micrograms of hormone, their hindgut Malpighian tubule extract was more attractive to female beetles in a laboratory bioassay than was extract from males producing pheromone naturally in ponderosa pine logs.  相似文献   
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Cells of the homogeneous hybrid line neuroblastoma x glioma (NG108-15) have many neuronal properties. Immunocytochemical tests show that they contain both immunoreactive renin and angiotensin; direct radioimmunoassays show that they are positive for renin, angiotensin I, and angiotensin II; enzymatic assays show that they contain angiotensinogen and converting enzyme as well. The renin appears to be present in an enzymatically inactive form that can be activated by trypsin and then blocked by antiserum to purified mouse submaxillary renin. Renin concentration and activity are increased by enhancing cellular differentiation with dibutyryl cyclic adenosine monophosphate or by serum withdrawal. These findings demonstrate a complete renin-angiotensin system within these neuron-like cells, and suggest that activation of intracellular renin could generate angiotensin II.  相似文献   
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The complex suite of organic materials in carbonaceous chondrite meteorites probably originally formed in the interstellar medium and/or the solar protoplanetary disk, but was subsequently modified in the meteorites' asteroidal parent bodies. The mechanisms of formation and modification are still very poorly understood. We carried out a systematic study of variations in the mineralogy, petrology, and soluble and insoluble organic matter in distinct fragments of the Tagish Lake meteorite. The variations correlate with indicators of parent body aqueous alteration. At least some molecules of prebiotic importance formed during the alteration.  相似文献   
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Anesthetic-associated death (AAD) in cats is infrequent, but occurs far more frequently than in people. Post-mortem investigations of AAD in cats are uncommon, and results only sporadically published. Here we report the findings in 54 cases of AAD in cats. Significant gross and/or microscopic pre-existing disease, including pulmonary, cardiac, and systemic disease, was detected in 33% of cases. Pulmonary disease was most frequently diagnosed (24% of cases), and included cases of Aelurostrongylus abstrusus infection (9% of cases). Heart disease, including two cases of hypertrophic cardiomyopathy, was less frequent (11% of cases). Four percent died from surgical complications. No?significant gross or microscopic disease was detected in 63% of cases. Additional studies are needed to determine if these findings are representative of AAD in cats in other geographic areas or with access to veterinary care. This study demonstrates that post-mortem investigation of AADs is an important and worthwhile endeavor.  相似文献   
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A 9-day old Grant's zebra with a 3-day history of lethargy, weight loss, inappetance, and diarrhea was treated with ampicillin, vitamin E and selenium, and tetanus antitoxin without effect in 24 h. On transfer to the local veterinary clinic, a grade IV/VI continuous heart murmur was detected and a patent ductus arteriosus found at necropsy.  相似文献   
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