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991.
RA Bruce T DeRouen DR Peterson JB Irving N Chinn B Blake V Hofer 《Canadian Metallurgical Quarterly》1977,39(6):833-840
In a follow-up study of 1,852 men with coronary heart disease, 195 deaths occurred within the first 3 years (33 +/- 13 months [mean +/- standard deviation]). Analysis of these cases indicated that the risk of sudden cardiac death in ambulatory men with clinical manifestations of coronary heart disease may be readily estimated from noninvasive clinical and exercise criteria. The important predictors are indexes of the severity of coronary heart disease and impairment of peak left ventricular function demonstrated with symptom-limited maximal exercise. The advantages of these predictors are that they may be elicited on the initial study as well as on follow-up noninvasive examinations of ambulatory patients. The appearance of nonelectrocardiographic predictors in serial examinations may provide an indication for invasive studies and be a more important finding than the ischemic S-T reponse to exertion. 相似文献
992.
993.
RS Sherwin W Tamborlane R Hendler L Saccá RA DeFronzo P Felig 《Canadian Metallurgical Quarterly》1977,45(5):1104-1107
Somatostatin was infused for 6 h into seven normal subjects with and without a replacement dose of glucagon. The addition of glucagon to somatostatin resulted in a 30-40% rise in plasma glucagon, whereas plasma insulin declined by 40-50% in both treatment groups. Plasma glucose and glucose production initially increased 2-fold with glucagon replacement, and subsequently declined by 2-3 h to levels comparable to those observed with somatostatin alone. After 6 h plasma glucose and glucose kinetics were no different whether or not glucagon was present. The rise in blood ketones after somatostatin was not exaggerated by glucagon replacement. We conclude that glucagon lack is not a modifying factor in the late hyperglycemic and hyperketonemic response to prolonged infusions of somatostatin. 相似文献
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997.
Basophilic stippling of the circulating erythrocytes is characteristic of the Mongolian gerbil. Its enzymatic digestion along with the concomitant removal of diffuse erythrocytic polychromasia by the action of ribonuclease demonstrates that it represents microscopically visible aggregates of cytoplasmic ribonucleoprotein, presumably of ribosomal origin. Up to 40% of the total circulating erythrocytes may be stippled in foetal and newborn animals. There is then a progressive decline in incidence until adult levels are attained at least by 20 weeks of age. The bone marrow of the adult gerbil contains a higher proportion of stippled red cells than the circulating blood. The stippling can be either coarse or fine and observable in both polychromatophilic and orthochromic cells. It is suggested that erythrocytes with basophilic stippling are relatively immature red cells still demonstrating remnants of cytoplasmic ribonucleoprotein. 相似文献
998.
We have used dacryoscintigraphy to study the efficiency of the lacrimal system following the repair of a divided lower canaliculus in 4 children. This test has been reliable in evaluating lacrimal function and suggests that a canaliculus can be repaired and splinted satisfactorily. Our experience with dacryoscintigraphy confirms that it is a safe comfortable, and reliable method for studying the patency of the lacrimal drainage system. 相似文献
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1000.
1. The biosynthesis of cholesterol was studied, by using various precursors, in rats subjected to several dietary regimes. 2. The use of 3H2O as a substrate to demonstrate differences in cholesterogenesis under various conditions was validated by using rats fed on cholesterol or cholestyramine. Cholesterol feeding resulted in decreased cholesterogenesis, whereas cholestyramine caused an increase. 3. With acetate as precursor, the biosynthesis of both digitonin-precipitable sterol and fatty acids was increased in vitro in response to a meal. 4. In rats fed ad libitum, hepatic cholesterogenesis was increased at midnight relative to mid-morning as measured by using acetate precursor in vitro. However, no such difference was found by using 3H2O in vivo. 5. The lipogenic response was measured in meal-fed rats by using 3H2O or octanoate in vivo. In contrast with findings with acetate in vitro, no postprandial stimulation of cholesterogenesis was seen with either 3H2O or octanoate as precursor, whereas fatty acid biosynthesis from either substrate was increased. 6. These findings are discussed with respect to current theories about the circadian rhythm of cholesterogenesis. Such theories are based on experiments using isolated enzyme measurements or non-physiological precursors such as acetate. 7. It is considered that results obtained with 3H2O give an accurate representation of cholesterogenesis under various conditions, and it is therefore suggested that hepatic cholesterogenesis in rats is not subjected to the same degree of diurnal rhythm as has previously been believed. 相似文献