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71.
Zusammenfassung: Seit nun mindestens zwei Jahren liegen durch wissenschaftliche Nachweise mehrfach best?tigte Befunde vor, die es gestatten, grunds?tzlich davon auszugehen, dass Fischleber – insbesondere die Leber von Dorschen aus der ?stlichen Ostsee – einen hohen Gehalt an Dioxinen und PCB aufweist. Im vorliegenden Kurzbeitrag wird dargelegt, inwieweit und ob die rechtlichen Regelungen auf EU-Ebene diesem Tatbestand Rechnung tragen und die Verbraucherinnen und Verbraucher vor dem unbedachten Verzehr solcher Fischleber mit hoher Dioxinbelastung schützen. Eingegangen: 18. Dezember 2007 相似文献
72.
Andrea Goldson Melanie Lam Christine H Scaman Sabine Clemens Allison Kermode 《Journal of the science of food and agriculture》2008,88(4):619-625
BACKGROUND: Oral therapy with phenylalanine ammonia lyase (PAL), naturally encapsulated in plant cells, may provide a potential alternative treatment for hyperphenylalaninemic patients, including those with phenylketonuria. Therefore different sources of plant tissue were investigated for PAL activity. RESULTS: Enzyme activity was highest in grain seedlings, with maximal enzyme activity in 7‐day‐old red spring wheat (Triticum aestivum L.) seedlings. The PAL activities of leaves and roots/endosperm of wheat seedlings were 11.90 ± 2.64 and 6.48 ± 1.59 µmol h?1 g?1 dry weight respectively. Three PAL‐related polypeptides with molecular weights of 74, 83 and 103 kDa were identified in wheat seedling leaf tissues, while only the 74 kDa polypeptide was detected in root/endosperm tissues. Dehydration was investigated as a method of concentrating PAL in wheat seedlings. Freeze‐drying was found to retain the most PAL activity (>90% recovery on a dry weight basis) compared with air drying and vacuum microwave drying for both leaf and root/endosperm samples. CONCLUSION: This study has led to a better understanding of PAL activity and stability in plant tissues and provides the basis for developing a natural plant preparation as a dietary supplement for the treatment of hyperphenylalaninemia. Copyright © 2007 Society of Chemical Industry 相似文献
73.
David A. Palandro Serge Andréfouët Chuanmin Hu Pamela Hallock Frank E. Müller-Karger Phillip Dustan Michael K. Callahan Christine Kranenburg Carl R. Beaver 《Remote sensing of environment》2008,112(8):3388-3399
The loss of coral reef habitats has been witnessed at a global scale including in the Florida Keys and the Caribbean. In addition to field surveys that can be spatially limited, remote sensing can provide a synoptic view of the changes occurring on coral reef habitats. Here, we utilize an 18-year time series of Landsat 5/TM and 7/ETM+ images to assess changes in eight coral reef sites in the Florida Keys National Marine Sanctuary, namely Carysfort Reef, Grecian Rocks, Molasses Reef, Conch Reef, Sombrero Reef, Looe Key Reef, Western Sambo and Sand Key Reef. Twenty-eight Landsat images (1984–2002) were used, with imagery gathered every 2 years during spring, and every 6 years during fall. The image dataset was georectified, calibrated to remote sensing reflectance and corrected for atmospheric and water-column effects. A Mahalanobis distance classification was trained for four habitat classes (‘coral’, ‘sand’, ‘bare hardbottom’ and ‘covered hardbottom’) using in situ ground-truthing data collected in 2003–2004 and using the spectral statistics from a 2002 image. The red band was considered useful only for benthic habitats in depths less than 6 m. Overall mean coral habitat loss for all sites classified by Landsat was 61% (3.4%/year), from a percentage habitat cover of 19% (1984) down to 7.6% (2002). The classification results for the eight different sites were critically reviewed. A detailed pixel by pixel examination of the spatial patterns across time suggests that the results range from ecologically plausible to unreliable due to spatial inconsistencies and/or improbable ecological successions. In situ monitoring data acquired by the Coral Reef Evaluation and Monitoring Project (CREMP) for the eight reef sites between 1996 and 2002 showed a loss in coral cover of 52% (8.7%/year), whereas the Landsat-derived coral habitat areas decreased by 37% (6.2%/year). A direct trend comparison between the entire CREMP percent coral cover data set (1996–2004) and the entire Landsat-derived coral habitat areas showed no significant difference between the two time series (ANCOVA; F-test, p = 0.303, n = 32), despite the different scales of measurements. 相似文献
74.
Wulfert Edelgard; Franco Christine; Williams Kevin; Roland Brian; Maxson Julie Hartley 《Canadian Metallurgical Quarterly》2008,22(3):380
Many gamblers claim that gambling is intrinsically exciting, with money playing only a secondary role. To examine the effects of the expectancy of winning money, the authors randomly assigned 243 male college student gamblers to 1 of 6 experimental or 1 of 3 control conditions. Control participants either simply watched a videotaped horse race or they picked a horse, but without wagering; that horse later turned out to be either the winner of the race or the runner-up. Experimental participants wagered $1 on a horse for a chance of winning either $2, $7, or $15, with half winning and half losing their wagers. Wagering led to increased heart rates and subjective excitement as a function of the expected payoff and of winning as opposed to losing the wager. The study was replicated with 200 female college student gamblers with similar results. These findings support the notion that the excitement of gambling is tied to the expectancy of winning money. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
75.
Glynn Laura M.; Schetter Christine Dunkel; Hobel Calvin J.; Sandman Curt A. 《Canadian Metallurgical Quarterly》2008,27(1):43
Objective: To determine whether the pattern of prenatal stress, as compared to prenatal stress assessed at a single gestational time point, predicts preterm delivery (PTD). Design: Perceived stress and anxiety were assessed in 415 pregnant women at 18-20 and 30-32 weeks' gestation. Main Outcome Measures: Gestational length was determined by last menstrual period and confirmed by early pregnancy ultrasound. Births were categorized as preterm ( 相似文献
76.
Nezu Arthur M.; Nezu Christine Maguth; Jain Diwakar 《Canadian Metallurgical Quarterly》2008,27(6):829
Objective: The present study tested the hypothesis that social problem solving (SPS) served to mediate the relationship between preceived stress and noncardiac chest pain (NCCP). Design: Adults undergoing stress myocardial perfusion imaging (MPI) to determine the presence of underlying cardiovascular disease related to the experience of chest pain were recruited prior to stress testing to complete a series of self-report inventories. Main Outcome Measures: MPI results were used to identify individuals with NCCP (N = 166; 91 men, 75 women; mean age = 53.92 years, SD = 11.98). Measures included perceived stress, SPS, and chest pain frequency and intensity. Results: In direct tests of the mediational effects of SPS, it was found that two problem-solving dimensions, negative problem orientation and rational problem solving, each served as significant mediators of the effects of stress on both NCCP intensity and frequency. Conclusion: These results support a mediational analysis of NCCP that includes stress and SPS. As such, it identifies SPS as a potentially important clinical target to consider when developing future psychosocial-based therapy protocols for treating individuals with NCCP. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
77.
Delforge Catherine; Le Scanff Christine; Fontayne Paul 《Canadian Metallurgical Quarterly》2008,40(1):42
Parents have an influence on the evolution of their child and his/her successes in school, sports or music. Their support by example is critical. Some of their behaviours can also have a negative impact. Research aiming at better defining parents/child relations and their influence on the successes and the well-being of the child is needed. To this end, the use of a questionnaire is profitable. But there are few valid tools available in French. The existing tools do not focus on the evaluation of essential dimensions of child development. To palliate this deficiency, this article aims at validating the QéRPE (Questionnaire d'évaluation des relations parents/enfant), the French translation of the EMBU (Egna Minnen Betr?ffende Uppfostran, Perris et al., 1980). It underscores the level of support, overprotection and reject felt by the child by his parents. It is applied here in a relation parents/sport. The factor pattern (exploratory and confirmatory analysis) and the internal consistency of the QéRPE have been tested, and an external validation has been made. Results show that the psychometrics quality of the QéRPE is very acceptable. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
78.
Charyton Christine; Jagacinski Richard J.; Merrill John A. 《Canadian Metallurgical Quarterly》2008,2(3):147
Psychology and engineering faculty developed a new assessment tool to measure creativity in engineering design (Creative Engineering Design Assessment or CEDA). Fifty-eight engineering students (52 men and 6 women) and 59 psychology students (27 men and 32 women) completed the CEDA as well as other general creativity measures (creative personality, creativity temperament, and cognitive risk tolerance). Interrater reliability for the overall CEDA was high (r = .98). On average, men and women displayed similar levels of creative personality, cognitive risk tolerance, and engineering creativity (CEDA scores). However, the CEDA scores exhibited a cross-over interaction between academic class (engineering and psychology) and gender. Women displayed more creativity temperament. Intertest correlations indicate that the CEDA is different from the other general creativity measures. These results suggest that engineering design creativity may be a specialized skill that needs to be honed in engineering students. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
79.
Vann Seralynne D.; Denby Christine; Love Seth; Montaldi Daniela; Renowden Shelley; Coakham Hugh B. 《Canadian Metallurgical Quarterly》2008,22(5):658
Despite increasing evidence that the fornix is important for memory, uncertainty remains about the exact nature of subsequent impairments arising from damage to this tract. This uncertainty is often created by pathology in additional brain structures. The present study involved a young man, DN, who had almost complete bilateral loss of the rostral columns of the fornix and much of the surrounding septum in the left hemisphere following the surgical removal of a cavernous angioma. Quantitative MRI analyses of structure size, normalized to intracranial volume, showed no difference in any of the additional brain regions measured, apart from those areas removed to expose the tumor. DN showed a marked, stable anterograde memory impairment that was still present 4 years postsurgery. In contrast, DN performed within normal levels on most tests of recognition memory. This sparing was most striking when given a 24-hr delay between study and test of the Warrington Recognition Memory Test. This recall/recognition dissociation provides further evidence for neuroanatomical divisions within recognition memory processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
80.
The authors investigated the impact of response activation on dual-task performance by presenting a subliminal prime before the stimulus in Task 2 (S2) of a psychological refractory period (PRP) task. Congruence between prime and S2 modulated the reaction times in Task 2 at short stimulus onset asynchrony despite a PRP effect. This Task 2 congruence effect was paralleled by a Task 1 congruence effect and emerged exclusively under conditions of cross talk, whereas it did not occur under dual-task conditions preventing cross talk between tasks. This suggests that response activation operates during the PRP in dual tasks and affects the response times in Task 2 via cross talk between common processing elements at prebottleneck stages but not by directly affecting the postbottleneck stages. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献