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91.
Cholecystokinin-octapeptide (CCK8) administered intraperitoneally (i.p.) in rats induces a rapid elevation in serum oxytocin (OT). The receptor subtype mediating this action of CCK was investigated with selective CCK-A and CCK-B receptor agonists and antagonists. CCK8 and A-71623, a potent CCK-A selective agonist, were similar in efficacy and potency for stimulating OT secretion. Both compounds at 10 nmol/kg elicited approximately one-half the response of 100 nmol/kg, which elevated serum OT to approx. 20 to 30-fold above basal level. The potent CCK-B selective agonist, A-63387, at doses up to 100 nmol/kg did not increase serum OT. MK-329, a CCK-A receptor selective antagonist, at a dose of 20 nmol/kg fully inhibited the action of 20 nmol/kg CCK8, while 100 nmol/kg of (R)L-365,260, a CCK-B selective antagonist, had no effect on the CCK8 response. These results, together with previous lesion studies, suggest that vagal CCK-A receptors in the periphery mediate the activation of the oxytocinergic pathway in vivo.  相似文献   
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An algorithm is presented, which is designed to identify blue-absorbing aerosols from near infrared and visible remote-sensing observations, as they are in particular collected by satellite ocean color sensors. The technique basically consists in determining an error budget at one wavelength around 510 nm, based on a first-guess estimation of the atmospheric path reflectance as if the atmosphere was of a maritime type, and on a reasonable hypothesis about the marine signal at this wavelength. The budget also includes the typical calibration uncertainty and the natural variability in the ocean optical properties. Identification of blue-absorbing aerosols is then achieved when the error budget demonstrates a significant over-correction of the atmospheric signal when using non-absorbing maritime aerosols. Implementation of the algorithm is presented, and its application to real observations by the MERIS and SeaWiFS ocean color sensors is discussed. The results demonstrate the skill of the algorithm in various regions of the ocean where absorbing aerosols are present, and for two different sensors. A validation of the results is also performed against in situ data from the AERONET, and further illustrates the skill of the algorithm and its general applicability.  相似文献   
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Despite the fact that a large number of homosexual couples seek professional help when confronted with marital difficulties, relatively little knowledge is available to psychologists working with these clients. Although gay and lesbian couples greatly resemble heterosexual couples on most of the conjugal dimensions, it seems that same sex couples do have a unique reality to their sexual orientation. The present article constitutes an innovative synthesis of the actual knowledge concerning therapeutic intervention with gay and lesbian couples. First, the specific motives for these couples to seek help are discussed (i.e., issues related to homophobia, the lack of conjugal models, the "coming out" process, and the influence of socialization). Then, changes relating to issues relevant to some same sex couples brought to theoretical frameworks in psychology are explored. The frameworks that we examine are psychoanalytic, adlerian and cognitive behavioural. Finally, issues associated with HIV are discussed given its importance for die homosexual population and its impact on gay couples. This article, far from wanting to stigmatize even more homosexual couples, aims to support psychologists in their reflection and search for adequate interventions with this population that still... (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Four studies examined gender differences in self-construals and the role of social comparison in generating these differences. Consistent with previous research, Study 1 (N=461) showed that women define themselves as higher in relational interdependence than men, and men define themselves as higher in independence/agency than women. Study 2 (N=301) showed that within-gender social comparison decreases gender differences in self-construals relative to a control condition, whereas between-genders comparison increases gender differences on both relational interdependence and independence/agency. Studies 3 (N=169) and 4 (N=278) confirmed these findings and showed that changing self-construal changes gender differences in social dominance orientation. Across the 4 studies, strong evidence for the role of in-group stereotyping as mediator of the effect of gender on self-construal was observed on the relational dimension but not on the agentic dimension. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The increasing resistance of Plasmodium falciparum to the most commonly used antimalarial drugs makes it necessary to identify new therapeutic targets. The telomeres of the parasite could constitute an attractive target. They are composed of repetitions of a degenerate motif ((5')GGGTTYA(3'), where Y is T or C), different from the human one ((5')GGGTTA(3')). In this report we investigate the possibility of targeting Plasmodium telomeres with G-quadruplex ligands. Through solution hybridisation assays we provide evidence of the existence of a telomeric 3' G-overhang in P. falciparum genomic DNA. Through UV spectroscopy studies we demonstrate that stable G-quadruplex structures are formed at physiological temperature by sequences composed of the degenerate Plasmodium telomeric motif. Through a FRET melting assay we show stabilisation of Plasmodium telomeric G-quadruplexes by a variety of ligands. Many of the tested ligands display strong quadruplex versus duplex selectivity, but show little discrimination between human and Plasmodium telomeric quadruplexes.  相似文献   
99.
Biological Functions and Metabolism of Oleoylethanolamide   总被引:2,自引:0,他引:2  
The present review is focused on the metabolism and the emerging roles of oleoylethanolamide (OEA) with emphasis on its effects on food intake control and lipid metabolism. The biological mechanism of action, including a non-genomic effect mediated through peroxisome proliferator-activated receptor alpha (PPAR-alpha) and transient receptor potential vanilloid type 1 (TRPV1) receptor, is discussed. The research related to fatty acid ethanolamides has been focused until recently on anandamide and its interaction with cannabinoid receptor subtype 1. The roles of other N-acyl ethanolamine fatty acid derivatives have been neglected until it was demonstrated that OEA can modulate food intake control through interaction with PPAR-alpha. Further investigations demonstrated that OEA modulates lipid and glucose metabolism, and recent study confirmed that OEA is an antagonist of TRVP1. It has been demonstrated that OEA has beneficial effects on health by inducing food intake control, lipid beta-oxidation, body weight loss and analgesic effects. The investigation of the mechanism of action revealed that OEA activates PPAR-alpha and stimulates the vagal nerve through the capsaicin receptor TRPV1. Pre-clinical studies showed that OEA remains active when administered orally.  相似文献   
100.
European corn borer larvae detect and avoid feeding in the presence of phytoecdysteroids (PEs) such as 20-hydroxyecdysone (20E). Therefore, we hypothesized that females would have taste receptors similar to larvae and avoid laying eggs in the presence of 20E. We found female-specific taste sensilla on the tarsi that respond to 20E at concentrations as low as 10−6 M, a threshold comparable to that of larvae. However, in choice tests, females laid a similar number of eggs on 20E-treated and on nontreated artificial substrates (filter paper, glass, and nylon), although they spent significantly more time in behavioral sequences related to substrate assessment when 20E was present. In contrast, when given a choice between maize plants (eight leaves) sprayed with 20E or only the solvent, females laid 70% fewer eggs on the treated than on control plants. These observations suggest that other chemical cues of plant origin must be present at the same time as 20E for females to modify their oviposition behavior.  相似文献   
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