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991.
992.
993.
Because it is frequent and variable by sex, age and culture, manifest aggression in dreams appears to be an important research area. A comparison was made between dreamed aggressions for Americans (Hall and Domhoff 1963) and for Zapotecs, collected and analysed by the writers. Similarities and differences revealed in the comparison, suggest the importance of cultural factors in manifest dreamed aggression, along with sex and age. Multivariate analyses of carefully collected cross-cultural data will be necessary before adequate assessments can be made of the relative importance of these variables in dreams, more clearly establishing relationships between wakeful and dreamed experiences. 相似文献
994.
The results reported here show some characteristics of adenylate cylase (EC 4.6.1.1) derived from homogenates of rat spleen, and describe the in vitro stimulation of this enzyme by prostaglandins, nucleotides, and F- under conditions where cyclic nucleotide degradative pathways are effectively inhibited. Particulate fractions from rat spleen homogenates contain high adenylate cyclase activities, and the highest specific activity is recovered in a particulate fraction prepared by low speed (1200 X g) centrifugation. Activity found in all particulate fractions is stimulated by fluoride, prostaglandins E1 and E2, catecholamines, and purine nucleotides. No stimulation is caused by prostaglandins F1 alpha and F2 alpha. Stimulation by prostaglandin E1 and E2 is augmented by GTP and other purine nucleotides, and stimulation by the combination of GTP and prostaglandin E1 is equal to that caused by optimal fluoride concentrations. Stimulation caused by L-isoproterenol is additive to that caused by GTP but is not increased by GTP. 相似文献
995.
M Ryan PJ Phizackerley TJ Ryan JP Ellis SM Powell 《Canadian Metallurgical Quarterly》1976,94(6):607-610
The apparent Michaelis constant (Km) for glucose-6-phosphate of the enzyme glucose-6-phosphate dehydrogenase has been measured in extracts prepared from biopsies of normal human skin and from both affected and apparently normal skin of patients with lichen planus. No differences of Km were found and starch gel electrophoresis of extracts from lichen planus lesions and normal controls showed similar patterns when stained for glucose-6-phosphate dehydrogenase activity. These results do not support the view that lichen planus is an inborn error of metabolism in which the structure of glucose-6-phosphate dehydrogenase of skin is affected. 相似文献
996.
DE Kuhl RQ Edwards AR Ricci RJ Yacob TJ Mich A Alavi 《Canadian Metallurgical Quarterly》1976,121(2):405-413
The Mark IV scanning system is a simple four-sided arrangement of 32 independent detectors which rotate continously as a unit, detecting, processing, and displaying the reconstructed data while the study progresses. Detection is by single photon counting and is compatible with commercially available radionuclides. An empirical correction is applied for attenuation, difference in detector response, and scatter. It is a high-sensitivity device with approximately uniform resolution throughout the section plane. There is good reproducibility and accuracy for absolute quantification of radionuclide concentration in the brain. Clinical applications include scans of 99mTcO4, 99mTc-RBC, 123I-iodoantipyrine, 99mTc-diphosphonate, and 111In-DTPA. 相似文献
997.
TJ Kriewall 《Canadian Metallurgical Quarterly》1976,41(3):316-322
This paper presents a theoretical analysis relating work expended by the uterus to the synergistic relationship between intrauterine pressure (IUP) and cervical dilatation (CD). By utilizing a geometrical model for the fetal presenting part which is assumed to be in contact with the cervix, the changes in internal volume of the uterus with each contraction can be shown to be functionally related to cervical dilatation. Thus work, expressed in terms of foot-pounds, can be calculated using the integral of pressure times incremental volume. By simulating intrauterine pressure and cervical dilatation with continuous analytical wave forms, the alterations required in uterine work to dilate the cervix are calculated for various wave-form aberrations which are seen in clinical situations. The wave-form aberrations are applied to an elastic cervical model as well as a viscoelastic model. Using the principles of thermodynamics the areas of the fetouterine complex which absorb the work generated by the contractions are defined. It is shown that the efficiency of the contractions to dilate the cervix can be calculated by evaluating the work expended in these various areas of energy absorption. The purpose of this paper is to present the theory upon which clinical findings in obstetrics can be based so that conclusions drawn will be technically sound. 相似文献
998.
TJ Nevalainen 《Canadian Metallurgical Quarterly》1976,92(20):1167-1182
999.
A study was carried out to define the time limits during which an experimental coronary thrombus remains capable of incorporating fibrinogen. 131I-fibrinogen was given to intact anesthetized dogs at different time intervals, up to 67 hours, following the formation of a coronary thrombus by catheter-electrode. Radioactivity of the recovered thrombi as a whole and segmentally divided, was determined following variable time intervals of exposure to circulating fibrinogen and was expressed as thrombus/blood ratio. The results indicate that coronary thrombi formed in a normal coronary vessel remain capable of incorporating fibrinogen for at least eighteen hours, with no significant differences in the segmental distribution of radioactivity. These findings do not support the view that the recovery of isotopic fibrinogen, which was given after the onset of coronary symptoms, in thrombi from patients with myocardial infarction establishes that the thrombus was initiated after the ischemic process. 相似文献
1000.
The interaction between tetracyclines and di- and trivalent ions such as are contained in aluminium, magnesium, calcium, iron and zinc-containing salts or complexes or antacids is well documented. The potential for interaction between tetracyclines and zinc and bismuth salts is often not realised, but is emphasised by the findings reported here. The absorption of 250 mg phosphate-potentiated tetracycline hydrochloride was reduced by 75% when administered concurrently with 220 mg zinc sulphate. The absorption of 250 mg phosphate-potentiated tetracycline hydrochloride was reduced by 50% when administered concurrently with 10 ml bicitropeptide, a bismuth-protein complex. Tetracyclines should thus not be administered concurrently with zinc salts or bicitropeptide. 相似文献