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991.
Oral whisky is a potent stimulus of calcitonin secretion. Peak increments of immunoreactive calcitonin are observed within 15 min after the ingestion of 50 ml of whisky; the magnitude of the response is similar to that observed during a four-hour calcium infusion. This procedure has several advantages over standard methods of stimulating calcitonin release in patients at risk of developing medullary carcinoma of the thyroid, and this is shown by a study in a large family with familial chromaffinomatosis.  相似文献   
992.
A simple open-arena olfactometer to assay behavioral chemicals with pedestrian insects has been developed for the southern pine beetle. The olfactometer is constructed of Plexiglas and uses a single airstream. A feature of the olfactometer is the use of a clock-driven elution device that permits continuous release of liquid materials into the olfactometer airstream.This is Texas Agricultural Experiment Station Paper No. 12324. The work herein reported was funded in part by McIntire-Stennis project 1525, USFS Southern Forest Experiment Station cooperative agreement 19–145 and the USDA sponsored program entitled The Expanded Southern Pine Beetle Research and Applications Program through CSRS grant 516-15-70. The findings, opinions, and recommendations reported herein are those of the authors, and not necessarily those of the USDA.  相似文献   
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In Part I of this series new methods of parametric spectral analysis for a wide class of non-linear systems were introduced. In this, the second part, the interpretation and properties of the non-linear frequency response functions are discussed and illustrated by example.  相似文献   
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We have previously demonstrated that atropine pretreatment increases the incidence of fatal ventricular arrhythmias induced by left anterior descending coronary artery (LAD) occlusion. The purpose of the present study was to determine whether the deleterious effect of atropine also applies to arrhythmias induced by right coronary artery (RCA) occlsusion. Occlusion of the RCA resulted in ventricular arrhythmias in all 20 animals studied, followed by ventricular fibrillation in three animals (15 per cent). Right coronary occlusion also resulted in bradycardia (-30.3 +/- 5.1 beats per minute) and hypotension (-23.1 +/- 4.9 mm. Hg). Pretreatment of 15 animals with atropine caused no significant increase in the incidence of ventricular fibrillation (i.e., 20 per cent). In addition, atropine pretreatment had no effect on the fall in heart rate and hypotension associated with RCA ligation. Sectioning the vagus nerves produced results similar to atropine pretreatment with the exception that a significant portion of the bradycardia was prevented. These results indicate that the increase in deaths after atropine observed in animals undergoing experimental LAD occlusion in not demonstrated with RCA occlusion. The results also indicate that the potential for deleterious effects of atropine in acute infarction might depend on the anatomic location of the involved myocardium.  相似文献   
998.
The Venezuelan equine encephalitis epidemic which occurred in Texas in 1971 produced a wide range of predominantly mild clinical symptoms. This epidemic, which peaked on 13-14 July, was most intensely felt in the far-south counties of Cameron and Hidalgo. In all, 88 laboratory-confirmed human cases were reported to the U.S. Center for Disease Control by the Texas State Department of Health. The ratio of male to female cases was about two to one. An attack of 20.8 cases per 100,000, observed in both the 20-29 and 30-39 age groups, was higher than attack rates experienced by other age groups and by the population at large. Together, Cameron and Hidalgo counties experienced a much higher overall attack rate (21.7 cases por 100,000) than did affected counties in the Corpus Christi area (4.9 cases per 100,000). Knowledge about when various patients were first exposed points to an incubation period ranging from 27.5 hours to four days. In those 79 cases for which clinical data were available, the most common clinical manifestations were found to be fever, severe headache, myalgia, and chills. Evidence of mild to moderate central nervous system involvement was found in 10 out of 25 children and young people under 17 years of age, and in six out of 54 adults. Two children still had residual paralysis six weeks after onset of illness, but by 10 months these sequelae had disappeared. Seven of the 54 adults, however, still complained of tiring easily a year after onset of illness. Leukopenia, as demonstrated by a count of less rhan 4,500 white blood cells per cubic millimeter, was observed in 75 per cent of the patients examined.  相似文献   
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