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Forty Ss, 20 males and 20 females, observed a videotape that showed four males interacting in a social setting under four different drug conditions; coltsfoot, placebo, marijuana low dose, and marijuana high dose. The observers attempted to discriminate the level of intoxication of the four males in each condition. The observers accurately detected the level of intoxication in the high dose condition. While marijuana experienced users were more successful in detecting levels of intoxication, the sex of the observer was not significant. Behaviors used to discriminate intoxication and the implications of these results to defining intoxication are discussed.  相似文献   
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The distribution of iodinated margatoxin ([125I]margatoxin) binding sites in rat was investigated by autoradiography. Rat striatum expresses a high density of margatoxin binding sites and, therefore, the effects of margatoxin, charybdotoxin and iberiotoxin have been studied on [3H]dopamine release from rat striatal slices in vitro. Margatoxin (0.1-100 nM) and charybdotoxin (10-1000 nM), but not iberiotoxin increased the spontaneous and the electrically evoked [3H]dopamine release. [3H]dopamine release by margatoxin was inhibited by tetrodotoxin and omega-conotoxin GVIA, but not by atropine, naloxone, N(omega)-nitro-L-arginine and neurokinin or neurotensin receptor antagonists. In the buffer solution used for release experiments, [125I]margatoxin labels a maximum of 0.12 pmol of sites/mg protein in rat striatal membranes with a Kd of 5 pM. [125I]margatoxin binding was inhibited by margatoxin (Ki of 4 pM), charybdotoxin (Ki of 162 pM) but not by iberiotoxin. We conclude that inhibition of margatoxin-sensitive voltage-gated K+ channels increases [3H]dopamine release demonstrating their role in repolarization of nigrostriatal projections. In contrast, iberiotoxin-sensitive, high-conductance Ca2+-activated K+ channels are not involved in release of [3H]dopamine.  相似文献   
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Previous research has indicated that individual foods or beverages are ingested independently and do not produce adjustments to the intake of other constituents in the diet (de Castro, 1993; Wilson, 1991). In order to eliminate time of day as a potential contaminant, the present study investigated the accommodation of foods and beverages into the amount ingested at large evening meals only. Adults (n = 601) were paid to maintain detailed diaries of the timings, quantities and preparation techniques of everything they ingested for seven consecutive days. With the exceptions of soup, beef and chicken, 12 out of 15 types of drinks or foods were found to add to the total calories ingested in evening meals without displacing calories ingested in other forms, while ingestion of non-caloric diet sodas was not associated with differences in intake. The fat and protein, but not carbohydrate, contents of the items correlated with a measure of the satiating properties of the particular food or beverage, namely the correlation between the amount ingested of the particular type and the amounts of other nutrients ingested in the meal. The results confirm that intake at a meal is quite elastic and can be significantly influenced by the presence or absence of particular components of the meal and their constituents.  相似文献   
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Structural and morphologic changes in peripheral blood neutrophilic leukocytes were examined with the aim to diagnose and predict the clinical course of acute pyoinflammatory maxillofacial diseases. Classification of structural and morphologic signs of neutrophilic leukocyte activation levels during odontogenic pyoinflammatory diseases were studied using optic and electron microscopy. There degrees of neutrophilic leukocyte activation were distinguished: inactive, moderately active, and hyperactive. Inactive cells occurred in normal subjects and patients with mild forms of the disease, moderately active ones in patients with mild and medium-severe condition, hyperactive ones in those with medium-severe and grave disease. Increased count of hyperactive neutrophilic leukocytes in the peripheral blood was a sign predicting a grave clinical course of the disease with complications.  相似文献   
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