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Discusses the proliferation of crisis telephone services, which are usually staffed by nonprofessionals. When psychologists offer their services to these organizations, they are usually met with resentment. Perhaps the best role for psychologists would be assisting in training the volunteers. Training methods include didactic sessions and role playing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Expression of nucleoside diphosphate(NDP) kinase, which is homologous to the nm23 gene product in a variety of species, has been found to be inversely associated with metastatic potential. However, the relationship remains controversial according to the tumor cell types and experimental system, with conflicting results from different research groups. In order to determine whether NDP kinase expression serves as a marker for metastatic potential in human skin cancer, we assessed the levels of NDP kinase expression in 9 keratoacanthomas (KAs), 26 squamous cell carcinomas (SCCs), and 25 basal cell carcinomas (BCCs) using immunohistochemistry. The expression of NDP kinase was intense in KA and SCC compared with BCC. However, the difference of NDP kinase expression between KA and SCC was not statistically significant. And there was no statistically significant difference in NDP kinase expression between SCC with metastasis and SCC without metastasis. Our results contradict the hypothesis concerning the possible role of nm23 gene as a metastatic suppressor gene in human skin cancer. The mechanism of overexpression in various tumor cell types and its biological significance in cutaneous carcinogenesis remain to be determined.  相似文献   
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Problem, research strategy, and findings: We draw on a multidisciplinary body of research to consider how planning for urban agriculture can foster food justice by benefitting socioeconomically disadvantaged residents. The potential social benefits of urban agriculture include increased access to food, positive health impacts, skill building, community development, and connections to broader social change efforts. The literature suggests, however, caution in automatically conflating urban agriculture’s social benefits with the goals of food justice. Urban agriculture may reinforce and deepen societal inequities by benefitting better resourced organizations and the propertied class and contributing to the displacement of lower-income households. The precariousness of land access for urban agriculture is another limitation, particularly for disadvantaged communities. Planners have recently begun to pay increased attention to urban agriculture but should more explicitly support the goals of food justice in their urban agriculture policies and programs.

Takeaway for practice: We suggest several key strategies for planners to more explicitly orient their urban agriculture efforts to support food justice, including prioritizing urban agriculture in long-term planning efforts, developing mutually respectful relationships with food justice organizations and urban agriculture participants from diverse backgrounds, targeting city investments in urban agriculture to benefit historically disadvantaged communities, increasing the amount of land permanently available for urban agriculture, and confronting the threats of gentrification and displacement from urban agriculture. We demonstrate how the city of Seattle (WA) used an equity lens in all of its programs to shift its urban agriculture planning to more explicitly foster food justice, providing clear examples for other cities.  相似文献   

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1. Cyanopindolol (CYP) is a potent antagonist at the beta 3-adrenoceptor in rat ileum. Several analogues of CYP and pindolol were synthesized that also produced antagonist effects at the beta 3-adrenoceptor. However, at high concentrations, these compounds appear to act as "partial agonists'. This study was conducted to determine the structural requirements of CYP analogues necessary for antagonist activity and to examine the possibility that the agonist effects of CYP and its analogues may occur through a mechanism independent of beta-adrenoceptor activation. 2. Analogues of CYP and pindolol were tested for antagonist activity in rat ileum in which the beta 1- and beta 2-adrenoceptors were blocked. Fourteen compounds were tested against (-)-isoprenaline, and four of the more potent analogues were then tested against BRL 37344. The two most potent antagonists were CYP and iodocyanopindolol. The pKb values (negative log of equilibrium dissociation constant) obtained against (-)-isoprenaline were significantly higher than those obtained against BRL 37344, but the cause of this difference is not known. 3. Several structural requirements were determined for antagonist activity. Modification at the carbon atom alpha to the secondary amine caused the antagonist potency to fall as the level of saturation was reduced. Thus, a quaternary carbon group, such as t-butyl, produced the most potent antagonist. Substitution with a large moiety such as a cyclohexyl or benzyl group reduced antagonist activity, probably due to steric hindrance. Inclusion of an electron-withdrawing group, such as a cyano or ethylester moiety, alpha to the indole nitrogen, also increased the potency. Iodination of CYP and ethylesterpindolol at the 3-position of the indole ring did not increase antagonist potency. In contrast, iodination of the almost inactive analogues produced a significant increase in potency, suggesting that a beneficial electronic effect on the indole ring imparted by the iodo moiety may be able to offset partially the negative effects caused by either the steric hindrance, of lack of a quaternary carbon alpha to the secondary amine. 4. Values for pseudo-pD2 were also determined by conducting cumulative concentration-response studies up to the limit of drug solubility. For nine of the compounds tested, the pKb was significantly higher than the pseudo-pD2 value. 5. The discrepancy between the pKb and pseudo-pD2 values was examined further. The agonist effects of iodocyanopindolol, the agonist with the highest potency, were not antagonized by CYP which was the most potent antagonist of (-)-isoprenaline and BRL 37344 at the beta 3-adrenoceptor. This suggests that the agonist effects of iodoCYP were produced through a different mechanism: either via another receptor, another isoform of the rat beta 3-adrenoceptor, or through a non-receptor-mediated effect. Pseudo-pD2 values did not correlate with log P values for these compounds, indicating that their relaxant effects were not simply a function of their lipid solubility. 6. This study has highlighted several structural requirements for antagonist binding potency at the rat ileum beta 3-adrenoceptor and should assist in the development of potent selective antagonists for this receptor.  相似文献   
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Hoey C  Sherer M 《Food management》1994,29(3):74-7, 80, 82-4
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The effects of the Anemonia sulcata toxin ATX II on action potentials and contractility of isolated papillary muscles and single myocytes from rat and guinea-pig hearts have been studied. ATX II prolonged the action potential in both rat and guinea-pig papillary muscle. Although it produced a positive inotropic effect in guinea-pig papillary muscle, it failed to do so in rat papillary muscle. However, in single rat and guinea-pig ventricular cells, it both prolonged the action potential and had a positive inotropic effect. We suggest that ATX II does not cause a positive inotropic effect in rat papillary muscle, because it induces Ca2+ overload. In single cells the positive inotropic effect was reduced by approximately 50% when the contractions were triggered by voltage clamp pulses of constant duration rather than by action potentials. This suggests that the inotropic effect of ATX II is in part the result of the prolongation of the action potential. The intracellular Na+ activity (a(i)Na) in single ventricular cells was measured with the Na(+)-sensitive fluorescent dye SBFI. After exposure of the cells to ATX II, a(i)Na was increased by a maximum of 1.9 +/- 0.3 and 2.2 +/- 0.3 mM in rat and guinea-pig cells, respectively. It is suggested that the positive inotropic effect of ATX II is also in part the result of the rise in a(i)Na.  相似文献   
40.
Reefs of the tube-building polychaete Lanice conchilega are known to represent hotspots of biodiversity within inter- and subtidal soft sediments of the North Sea. However, because of their patchy distribution, point sampling does not appropriately map their subtidal spatial distribution. This study evaluated the feasibility to detect L. conchilega reefs by very-high resolution side-scan sonar imagery. A subtidal very-high resolution (410 kHz) side-scan survey, combined with grab sampling, revealed high densities of L. conchilega (up to 1979 ind. m? 2) to coincide with a higher reflectivity, patchy and grainy acoustic facies. From the side-scan sonar imagery, individual reefs were estimated to reach a maximum size of 15 m2. To ground truth the acoustic facies, the distribution of intertidal L. conchilega reefs was mapped at low tide and side-scan sonar imagery was recorded during the following high tide. Intertidal L. conchilega reefs had a patch size of 0.8 m2 up to 11.6 m2, elevated 7.5 to 11.5 cm above the surrounding seafloor and covered approximately 10% of the selected area. The very-high (445 kHz) resolution side-scan sonar imagery revealed a similar acoustic facies as in the subtidal. Lower-resolution (132 kHz) side-scan sonar imagery was less efficient to detect physically less developed L. conchilega reefs. We conclude that (1) there are no major technical restrictions to map L. conchilega reefs using side-scan sonar, (2) the developmental stage of L. conchilega reefs impacts the detectability of the reefs, and (3) very-high resolution side-scan sonar imagery is considered a necessity when mapping small-scale structures, such as L. conchilega reefs.  相似文献   
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