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21.
The Doppler examination of the carotid arteries in the neck was compared with the results of the examination of the supratrochlear artery and of the angiographic controls in 76 patients. The results of this study indicate that the insonation of the carotid arteries considerably improves the diagnostic possibilities offered by the examination of the supratrochlear artery alone. There are three main advantages: 1. The reliability of the Doppler examination is improved. The insonation of the carotid arteries of the 76 angiographically controlled patients including stenoses from 50% onward gave only one false-positive and one false-negative result. The percentage of correct diagnoses thereby attained was 97%. 2. The insonation of the carotid arteries permits reliable differentiation between stenoses and occlusions. This is not possible by the insonation of the supratrochlear artery alone. There was only one case in which the distinction was wrong. 3. The localization of the pathologic process was possible in all cases. These conclusions are only valid for the detection of occlusions and stenoses of more than 50%. Low degree stenoses cannot be detected by this method.  相似文献   
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Two experiments were conducted to determine the effect of acute heat stress on late-stage chicken embryos. Embryos were incubated at a normal control temperature (37.5 degrees C.) for 16 days and were then subjected to 40.6, 43.3, 46.1 or 48.9 degrees C. for various periods of time in another incubator of the same type. At the end of the stress period all embryos were placed back into the control incubator for the remainder of the incubation period. Exposure of embryos for 24 hours to a temperature of 40.6 degrees C, caused no major detrimental effects on hatchability. Exposure for 6 hours to the temperature of 43.3 degrees C, caused a decrease in hatchability with a severe decline in hatchability occurring after 9 hours of exposure. Exposure to 46.1 degrees C. for 3 hours or 48.9 degrees C for 1 hour killed all embryos. Chicks which hatched following a severe heat stress had a high incidence of clubbed, wiry down and exhibited an unsteady gait.  相似文献   
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A series of [(2-nitro-1-alkenyl)aryloxy]acetic acids was synthesized and tested in dogs for saluretic and diuretic activity. A number of these compounds exhibit a high order of activity on iv or po administration; representative of these is (E)-[2,3-dichloro-4-(2-nitropropenyl)phenoxy]acetic acid (5). The most highly active compounds are qualitatively similar in action to [2,3-dichloro-4-(2-methylenebutyryl)phenoxylacetic acid (ethacrynic acid) in causing a prompt increase in the excretion of water and of sodium and chloride ions in approximately equimolar amounts but are three to five times as potent. Potassium ion excretion is increased but less markedly than sodium excretion.  相似文献   
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The presence of aromatic 1-amino acid decarboxylase (AADC) in nerve cell bodies of the intrinsic plexuses of the guinea-pig small intestine was demonstrated by incubating segments of intestine with 1-dopa in the presence of an inhibitor of monoamine oxidase, pargyline. After such incubation, some nerve cell bodies gave a fluorescence histochemical reaction indicative of the presence of a decarboxylated product of 1-dopa, probably dopamine. No fluorescence reaction occurred in the unincubated control or if the inhibitor of AADC, RO 4-4602, was included in the incubation mixture. The AADC-containing cell bodies apparently do not take up and store dopamine, because no fluorescence could be detected after incubation with dopamine and a monoamine oxidase inhibitor. The AADC-containing cells were found in about half of the ganglia of the submucous plexus of the guinea-pig small intestine, but were considerably less frequent in the myenteric plexus. They were also found in the other areas examined in this study, that is, in both enteric plexuses of the guinea-pig distal colon and of the small intestines of rabbits and rats.  相似文献   
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The effect of prostaglandins (PGs) on the hepatic biotransformation of hexobarbital (Hechi) and p-chloro-N-methylaniline (PCMA) was determined in male rats. PCMA metabolism in slices was decreased by all PGs (PGA1, PGB1, PGE1, PGE2, PGF1alpha, PGF2alpha), ranging in concentration from 1 mu M to 1 mM. PGA1, at 1 mM, produced the greatest degree of inhibition, 39%. PG addition to microsomes, however, failed to alter PCMA metabolism. In contrast to PCMA biotransformation, Hechi metabolism was increased by all PGs in slices but not in liver subfractions. PGs of the E and F series were the most potent, producing a two-fold increase in Hechi metabolism at 1 mM after a 20 min preincubation. The increased effect was observed as early as 10 min and lasted for 4 hr. The relationship of PG metabolism and binding to cytochrome P-450 is presented as a possible mechanism to account for the opposite effects on Hechi and PCMA, type I and II substrates respectively, metabolism.  相似文献   
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Four light intensities were used in completely enclosed pigeon housed for 14 hours per 24 hours. Open front pens with only natural light were also used. There were four pens per treatment and five pairs of young, breeding age, White Carneaux per pen for 420 days. Results per treatment, 16, 30, 44 and 61 lumens per sq. m. and open pens, were respectively as follows for each objective: squabs raised-252, 220, 288, 203, and 212 with no significant differences except for the 44 lumen treatment which was higher than all others except 16; body wt./squab in g.-522, 526, 522, 508, and 531 at four weeks of age with no significant differences; feed per squab in kg.-4.7, 5.3, 4.5, 5.5, and 5.1 with only a significant difference between treatments 44 and 61 lumens; percent hatchability-89.7, 82.1, 89.6, 78.0, and 82.9 with no significant differences; percent squabs raised-93.7, 88.7, 97.9, 91.0, and 89.5 with no significant differences. The average number of squabs raised per treatment for all enclosed artifically lighted pens was 241 compared to 212 for the open pens with only natural light.  相似文献   
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