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41.
Butorphanol (levo-N-cyclobutylmethyl-3, 14-dihydroxy morphinan), a potent analgetic agent of the narcotic antagonist type with a low abuse potential in laboratory animals, was evaluated for antitussive activity in unanesthetized guinea-pigs and dogs. Subcutaneously, it was over 100 times more active than codeine, dextromethorphan and dl-pentazocine and about 20 times more active than morphine in the guinea-pig, while in the dog it was 100, 10 and 4 times more active than codeine, dl-pentazocine and morphine, respectively. Orally, butorphanol was 15-20 times more active than either codeine or dextromethrophan in both species. Naloxone reversed the antitussive effects of butorphanol, codeine, morphine and dl-pentazocine while those of dextromethorphan were not antagonized. The antitussive effect of butorphanol and morphine lasted about 4 hr and both compounds were longer acting than codeine. Butorphanol was also shown to be as effective against cough of pathological origin as against experimentally induced cough in the dog. 相似文献
42.
43.
Coturnix kept in a 14L:10D photoperiod from hatch began to lay their first eggs at a mean age of 42.8 days (range 38-55). Approximately 2/3 of Coturnix held from hatch in photoperiods of 6L:16D light were laying at 165 days of age. Mean age at first egg was 112.7 days (range 68-162 days) in 8L:16D and 130.8 days (range 117-158 days) in 6L:18D photoperiod. Coturnix transferred from a non-stimulatory (8L:16D) photoperiod to a stimulatory one (14L:10D or 24L) begun laying in 15-20 days if less than 140 days old, and in about 5 days if greater than 140 days old, when trasferred. Birds which has spontaneously begun to lay in an 8L:16D photoperiod did not stop laying when the photoperiod was reduced to 6L:18D. Those which began laying under 14L:10D photoperiod ceased laying in about 15 days if 89 or fewer days old when switched to 8L:16D, or in about 6 days if 140 or more days old. Those switched from 14L:10D to 6L:18D ceased laying in about 13 days when 76 days old, and 7 days when 89 days old. 相似文献
44.
Adrenergic receptors mediating depolarization in in vitro neonatal rat brown adipose tissue (BAT) have been characterized by use of adrenergic agonists and antagonists. Releasable endogenous catecholamine was present in BAT as demonstrated by tyramine- and 1,1-dimethyl-4-phenylpiperazinium iodide- (DMPP) induced depolarization in BAT from normal rats and its absence when BAT from reserpinized rats was used. In BAT from reserpinized rats l-norepinephrine, l-phenylephrine, and l-isoproterenol all similarly depolarized the bronw adipocytes over the concentration range of 10(-8) to 10(-6) M with a maximal depolarization of about 25 mV. Dopamine and d-norepinephrine were more than 100 times less potent. The beta-adrenergic blocker propranolol competitively inhibited isoproterenol-induced depolarization, whereas the alpha-adrenergic blackers, phentolamine and phenoxybenzamine, inhibited the phenylephrine-induced depolarization with much smaller inhibitory effects on the isoproterenol-induced depolarization. Both phenylephrine and isoproterenol elicited transient depolarizations when briefly added to the bathing medium while continuously recording from the same cell. Both the agonist and antagonist studies are interpreted as indicating the presence of both alpha- and beta-adrenergic receptors on BAT cells which mediate catecholamine-induced depolarization. 相似文献
45.
Fatty acid binding protein (FABP) is a protein of 12,000 mol wt found in cytosol of intestinal mucosa and other tissues, which exhibits high affinity for long chain fatty acids. It has been suggested that FABP (which may comprise a group of closely related proteins of 12,000 mol wt) participates in cellular fatty acid transport and metabolism. Although earlier findings were consistent with this concept, the present studies were designed to examine its physiological function more directly. Everted jejunal sacs were incubated in mixed fatty acid-monoglyceride-bile acid micelles, in the presence or absence of equimolar concentrations of either of two compounds which inhibit oleate binding to FABP:flavaspidic acid-N-methyl-glucaminate and alpha-bromopalmitate. Oleate uptake, mucosal morphology, and oxidation of [14C]acetate remained unaffected by these agents, but oleate incorporation into triglyceride was inhibited by 62-64% after 4 min. The inhibition by flavaspidic acid was reversible with higher oleate concentrations. The effect of these compounds on enzymes of triglyceride biosynthesis was examined in intestinal microsomes. Neither flavaspidic acid nor alpha-bromopalmitate inhibited acyl CoA:monoglyceride acyl-transferase. Fatty acid:coenzyme A ligase activity was significantly enhanced in the presence of partially purified FABP, probably reflecting a physical effect on the fatty acid substrate or on the formation of the enzyme-substrate complex. Activity of the enzyme in the presence of 0.1 mM oleate was only modestly inhibited by equimolar flavaspidic acid and alpha-bromopalmitate, and this effect was blunted or prevented by FABP. We conclude that in everted gut sacs, inhibition of triglyceride synthesis by flavaspidic acid and alpha-bromopalmitate could not be explained as an effect on fatty acid uptake or on esterifying enzymes in the endoplasmic reticulum but rather can be interpreted as reflecting inhibition of fatty acid binding to FABP. These findings lend further support to the concept that FABP participates in cellular fatty acid transport and metabolism. It is also possible that FABP, by effecting an intracellular compartmentalization of fatty acids and acyl CoA, may play a broader role in cellular lipid metabolism. 相似文献
46.
47.
An infant with a typical Edwards syndrome and a modal chromosome number of 46 is reported. In all cells analyzed one chromosome G was missing and an additional chromosome similar to a pair No. 16 was present. The phenotype of the child indicates that the extra element is a translocation between G and 18 chromosomes as in one case described previously. 相似文献
48.
JA De Lange WP Rutten NA Schmidt JG Eernisse JJ Veltkamp 《Canadian Metallurgical Quarterly》1976,14(10):485-497
In the routine laboratory for hematology conflicting results may be obtained for the red blood cell parameters with the Coulter Counter Model S. These parameters2) are: mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration (MCHC). When the values of the MCHC are above 36 g/dl something must be wrong with the blood sample of the patient. One of the reasons can be agglutination e.g. by cold agglutinins. The blood sample should be reanalysed before and after heating for 1 hour at 37 degrees C. If the values change: cold agglutinins are present; if no change occurs paraproteins, or other disturbing factors, such as bilirubin or high leucocyte levels, will be found. MCH values may also be high in some cases e.g. if the red blood cells are coated with antibodies (Coombs test positive) or after ingestion of medicines like Azathioprine. These examples show that it is possible in some cases to correlate immunological findings with the red blood cell parameters. In addition to the results with the Coulter Counter Model S, some observations on the Hemalog (Technicon) are also presented. 相似文献
49.
JA Donkersloot HA de Leon BM Chassy MI Krichevsky 《Canadian Metallurgical Quarterly》1976,32(3):448-450
The watery exudate produced by Streptococcus mutans SL-1 colonies on sucrose-containing agar media was found to contain about 7% (wt/vol) of a water-soluble, branched dextran, 4% sucrose, and smaller (less than 1%) amounts of fructose, Folin-phenol-positive material, and lactic acid. 相似文献
50.
Much attention has recently been focused on the question of the extent of heroin use in America. In a worthwhile effort to call public attention to the problem, many estimates of its size have evidenced a tendency toward exaggeration and aggrandizement. This paper presents methods of estimation of the extent of heroin addiction which, when carefully employed, should effectively correct such distorted estimates. Two general types of estimation are employed, incidence and prevalence. Incidence estimates are concerned with new cases of heroin addiction that occur in a specific population within a given amount of time. These estimates are based upon self-report data from addicts regarding date of first addiction. When corrected for the "lag phase" (that period of time between onset of first addiction and eventual visit to a treatment program), these data permit accurate retrospective charting of incidence trends. Prevalence estimates focus on all known cases of heroin addiction in a specific population within a given amount of time. Three separate types of prevalence estimates from three separate sources are outlined in this article: estimates based on overdose death data, estimates based on crime statistics, and estimates of "unknown" addicts. In outlining these methods, this article describes the fluctuations in heroin addiction in one major American city, San Francisco, California. After analyzing data gathered from a sample of 2,367 addicts contacted over a 3-year period, this study suggests that the incidence of heroin addiction seems to have declined after 1970. Possible factors underlying this apparent decline in heroin addiction are then discussed, including the post-1970 maturation of the "population at risk," the effectiveness of antidrug media messages, the changing drug fashions in the heroin subculture, and the gradual deterioration of the quality and potency of street heroin. 相似文献