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An increase was observed in the total protein mass of nuclei isolated from Chinese hamster ovary cells heated at 45 degrees C or 45.5 degrees C. An increase in the fractional recovery of DNA polymerase alpha and beta, and of DNA topoisomerase activity coincided with this increase in the protein mass of nuclei from heated cells. Nuclear protein mass which was soluble in 2.0 M NaCl decreased 0.5 fold, while DNA-associated and nuclear matrix-associated protein mass increased 2.2 and 3.4 fold, respectively. The results indicate that the increase in nuclear protein mass observed in nuclei from heated cells is due in part to an increased binding, or precipitation, of nuclear proteins onto the cell's DNA and nuclear matrix. 相似文献
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Blood-engorged Culex tarsalis (4,209) collected during 1960 to 1965 in Kern County, California and previously shown to have fed on passeriform birds by the precipitin test were further tested by the more sensitive passive hemagglutination inhibition test (PHI). It was shown that these mosquitoes fed principally on House Finches and House Sparrows, the most common passeriform birds found in the collection areas. These data demonstrate the usefulness of the PHI test for the identification of arthropod blood meals from closely related species. 相似文献
266.
BLOOD GLUCOSE, INSULIN (IRI), growth hormone, and plasma free fatty acids (FFA) were determined in six children consuming a diet of uneven distribution of protein relative to energy (study period). Preprandial and postprandial samples surrounding the 8 AM protein-free feeding and the 3 PM feeding containing all the day's protein were compared with values obtained in the same children similarly sampled while consuming an isonitrogenous isoenergetic diet of even protein distribution (control period). After the 8 AM feeding during the study period there was a mean maximal rise of blood glucose at 30 min of 51 mg/dl compared with a rise of 16 mg/dl during the control period. Glucose remained significantly elevated above fasting values at 120 min during the study but not the control period. IRI response after the 8 AM feeding was significantly greater and suppression of FFA was more marked during the study than during the control period. Glucose concentration 30 min after the 3 PM feeding was significantly lower during the study period than during the control period. A peak value occurred at 60 min during the study period which was equal to the 30 min peak control value. Despite the slower elevation of blood glucose during the study period, IRI rose at 30 min, possibly related to a larger influx of amino acids from the protein-containing meal. FFA rose at 30 and 60 min and were then suppressed by the slowly rising blood glucose. Growth hormone after both meals while consuming both diets was variable but considered normal. The qualitative changes in glucose-IRI-FFA responses were for the most part attributable to differences in the test meals and suggested little long-term adaptation to the uneven protein distribution diet. 相似文献
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AG Tilkian C Guilleminault JS Schroeder KL Lehrman FB Simmons WC Dement 《Canadian Metallurgical Quarterly》1976,85(6):714-719
Twelve patients with predominantly obstructive type sleep apnea underwent cardiac catheterization, hemodynamic monitoring, and arterial blood gas analysis during wakefulness and sleep. Abnormalities during wakefulness included systemic hypertension in four of 12, exercise-induced mild pulmonary hypertension in five of 12, and alveolar hypoventilation in one. During sleep nine patients had cyclic elevations of arterial pressure with each apneic episode, exceeding 200 mm Hg systolic in three of 12. Pulmonary artery pressures increased in 10 of 12, exceeding 60 mm Hg systolic in five. Marked degrees of hypoxemia (arterial P02, less than 50 mm Hg in eight of 12) and moderate hypercapnia with respiratory acidosis were associated with these hemodynamic changes. Cyclic upper airway obstruction during sleep may result in hypercapnia, acidosis, and pronounced hypoxemia, which can lead to hemodynamic abnormalities during sleep. Sustained pulmonary hypertension and possibly systemic hypertension may follow. Tracheostomy is an effective therapy and is recommended to symptomatic patients who have predominantly obstructive apnea but no relievable anatomic cause of upper airway obstruction. 相似文献
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During the synthesis of 3-hydroxy-3-ethinylquinuclidine (I), two additional products were isolated and identified as (E)-3-[2-(3-oxoquinuclidine)]quinuclidylidene (III) and (E)-3-[2-(3-hydroxy-3-ethinylquinuclidine)]quinuclidylidene (V). The base-catalyzed autocondensation of 3-quinuclidinone resulted in the alpha,beta-unsaturated ketone dimer (III) as a single isomer. The geometric configuration was deduced by examination of the NMR spectra of the methyl iodide salt. Compound V was thus the result of attack on the carbonyl carbon of III by the acetylide anion. The isolation and identification of these compounds clarified the reported differences in the physical properties of I and its analogs. 相似文献
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