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291.
Komulainen P Pedersen M Hänninen T Bruunsgaard H Lakka TA Kivipelto M Hassinen M Rauramaa TH Pedersen BK Rauramaa R 《Neurobiology of learning and memory》2008,90(4):596-603
Brain-derived neurotrophic factor (BDNF) is one of the key molecules modulating brain plasticity. While low circulating levels of BDNF have been suggested to predispose to Alzheimer's disease, very little data are available on its association with cognitive function in general population. We evaluated the association between plasma BDNF levels and cognition in a representative population sample of ageing men and women. The subjects (n=1389) were participants of the Dose-Responses to Exercise Training (DR's EXTRA) Study and represent a random sample of Eastern Finnish people (684 men and 705 women), 57-79 years of age at baseline of the study. Plasma BDNF levels were measured by enzyme-linked immunosorbent assay (ELISA). Cognitive function was evaluated using the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) neuropsychological test battery. Women had a higher mean (+/-SEM) plasma BDNF level than men (1721+/-55vs. 1495+/-54pg/ml, P<0.001). In women, 1 SD decrease in BDNF increased the risk for a low score in Naming Test by 53% (95% CI 1.21-1.92, P<0.001), in Mini-Mental State Examination by 63% (95% CI 1.21-2.20, P=0.001), in Word List Memory by 56% (95% CI 1.08-2.26, P=0.019), in Word List Recall by 50% (95% CI 1.10-2.05, P=0.010), in Word List Saving by 49% (95% CI 1.12-1.99, P=0.007), and in Word List Recognition by 64% (95% CI 1.19-2.25, P=0.002). Data were adjusted for age, education, depression, impaired glucose metabolism, cardiovascular disease, antihypertensive medication, lipid lowering medication, use of sex hormones, smoking, alcohol consumption, storing time of plasma in the freezer and platelet count. BDNF was not associated with cognition in men. Present data suggest that plasma BDNF is a biomarker of impaired memory and general cognitive function in ageing women. 相似文献
292.
Kakuk P 《Science and engineering ethics》2008,14(3):357-375
The discursive explosion that was provoked by the new genetics could support the impression that the ethical and social problems posed by the new genetics are somehow exceptional in their very nature. According to this view we are faced with special ethical and social problems that create a challenge so fundamental that the special label of genethics is needless to justify. The historical account regarding the evolution of the gene concepts could serve us to highlight the limits of what we know about genes and what we can do with genes. The widespread notion about the exceptionality of genetic knowledge and its applicative possibilities is hardly justifiable and leads to misunderstandings regarding the conceptualization of the ethical and social problems we might face. Following a more realistic interpretation of the role of genes in human life we might avoid a whole set of fictive dilemmas and counterproductive regulatory efforts in bioethics. Bioethical discourse should move from the gene-centered scientific discourse toward the more sophisticated and complex discourses where human development represented as a matter of complex interactions between genomes and environments, between genes, educational factors, nutritional regimes, and other different developmental resources. If a gene is seen as one among the different developmental resources that are shaping a given human trait then both genethics and genetic exceptionalism could hardly be represented as a justified approach in discussing the ethical and social problems of genetics. 相似文献
293.
This study set out to examine children’s notions of the malleability of their academic competencies and the relations of these
notions to the child’s grade-level and gender and the parent’s educational level. In interviews of a total of 103 boys and
girls of the third and the sixth grade, children of academically and vocationally educated parents were asked to rate their
potential for improving their competencies in mathematics and Finnish. The children were asked to use intrapersonal and normative
criteria in their ratings. The ratings were found to form distinct domains of the notions of malleability, as they did not
correlate with each other. The children’s ratings of their current competencies, i.e. their academic self-concepts, turned
out to be related to their normative ratings of the malleability of their competencies. The findings further suggested that
the children’s notions of the malleability of their academic competencies became more pessimistic in the course of their school
years.
相似文献
Kati KasanenEmail: |
294.
Ilg R Burazanis S Wohlschläger AM Wölleir A Wagenpfeil S Mühlau M 《Perception & psychophysics》2008,70(3):437-442
The temporal integration of continuous sensory information into a temporally extended percept becomes evident in spontaneous reversals of ambiguous apparent motion. To study the temporal relation of spontaneous percept reversals and temporal stimulus properties, we systematically varied presentation frequency in an ambiguous-apparent-motion paradigm. Moreover, we triggered percept reversals in a manner that was not consciously perceived by manipulating the duration of single frames. We found that the reversal rate depended on the stimulus frequency (with higher frequencies resulting in faster percept reversals) and that we could externally trigger perceptual reversals. Our findings support the idea that spontaneous reversals of ambiguous apparent motion are influenced by bottom-up effects at early processing levels. The paradigm allows for specific contrasts of spontaneous and externally triggered (but otherwise identical) perceptual reversals and, by this means, for further study of the underlying mechanisms. 相似文献
295.
David Dorn Justina A. V. Fischer Gebhard Kirchgässner Alfonso Sousa-Poza 《Journal of Happiness Studies》2008,9(2):227-255
We re-evaluate the relation between cantonal direct democracy and perceived subjective well-being in Switzerland using new
data from the Swiss Household Panel. In addition, this study goes beyond previous work by carefully controlling for cultural
determinants of happiness such as languages and religion. We find that once language is controlled for, no robust significant
relationship between the extent of direct democracy and life satisfaction can be observed. The results also show that direct
democracy does not affect well-being within language groups in Switzerland.
相似文献
Justina A. V. FischerEmail: |
296.
Offshore orientation in marine mammals is still a mystery. For visual orientation during night-time foraging and travelling
in the open seas, seals cannot rely on distant terrestrial landmarks, and thus might use celestial cues as repeatedly shown
for nocturnally migrating birds. Although seals detect enough stars to probably allow for astronavigation, it was unclear
whether they can orient by the night sky. The widely accepted cognitive mechanism for bird night-time orientation by celestial
cues is a time-independent star compass with learned geometrical star configurations used to pinpoint north as the rotational
centre of the starry sky while there is no conclusive evidence for a time-compensated star compass or true star navigation.
Here, we present results for two harbour seals orienting in a custom made swimming planetarium. Both seals learned to highly
accurately identify a lodestar out of a pseudo-randomly oriented, realistic projection of the northern hemisphere night sky.
Providing the first evidence for star orientation capability in a marine mammal, our seals’ outstanding directional precision
would allow them to steer by following lodestars of learned star courses, a celestial orientation mechanism that has been
known to be used by Polynesian navigators but has not been considered for animals yet. 相似文献
297.
Chimpanzees (Pan troglodytes) know what others can and cannot see in a competitive situation. Does this reflect a general understanding the perceptions of others? In a study by Hare et al. (2000) pairs of chimpanzees competed over two pieces of food. Subordinate individuals preferred to approach food that was behind a barrier that the dominant could not see, suggesting that chimpanzees can take the visual perspective of others. We extended this paradigm to the auditory modality to investigate whether chimpanzees are sensitive to whether a competitor can hear food rewards being hidden. Results suggested that the chimpanzees did not take what the competitor had heard into account, despite being able to locate the hiding place themselves by the noise. 相似文献
298.
Emotional-neutral pairs of visual scenes were presented peripherally (with their inner edges 5.2 degrees away from fixation) as primes for 150 to 900 ms, followed by a centrally presented recognition probe scene, which was either identical in specific content to one of the primes or related in general content and affective valence. Results indicated that (a) if no foveal fixations on the primes were allowed, the false alarm rate for emotional probes was increased; (b) hit rate and sensitivity (A') were higher for emotional than for neutral probes only when a fixation was possible on only one prime; and (c) emotional scenes were more likely to attract the first fixation than neutral scenes. It is concluded that the specific content of emotional or neutral scenes is not processed in peripheral vision. Nevertheless, a coarse impression of emotional scenes may be extracted, which then leads to selective attentional orienting or--in the absence of overt attention--causes false alarms for related probes. 相似文献
299.
The prospective study compares 31 patients in long-term behavior therapy with 31 patients in psychoanalytically oriented long-term therapy. A naturalistic design was applied within the German health system. All patients underwent a diagnostic interview (SCID) by an external interviewer. Only patients who fulfilled the DSM III-R criteria for a depression or an anxiety disorder were included in the study. Although the diagnoses of the patients undergoing long-term behaviour therapy and long-term psychoanalytical psychotherapy were comparable, we found that they differed in various ways. The differences arose in a number of characteristics, such as education, access to psychotherapy (recommended by professionals versus patients introducing themselves), usage of psychotropic medication, and the strain of symptoms. The average duration of long-term behavior therapy was 2.4 years and 64 sessions. The average duration of psychoanalytically oriented long-term therapy was 3.6 years and 209 sessions. Symptoms (SCL-90-R) and interpersonal problems (IIP) were examined at the beginning, after 1 year, 2.5 years, 3.5 years and after 7 years. Both groups showed significant degrees of improvement within the first 3.5 years and remained stabilized in the following 3.5 years regarding the symptomatic aspects. Focussing on the interpersonal problems, group PA showed further improvement after the 3.5-year period. The BT group however, showed no further improvement after 3.5 years but stabilized. The evaluated phase-model of psychotherapeutic change for short-term therapy was confirmed more clearly for long-term therapies of psychoanalytical orientation than for long-term therapies of behavioral orientation. 相似文献
300.
From June until August 2004 we asked 488 established psychological psychotherapists in selected German federal states for a subjective evaluation of their own health, their utilization of the health care system and their health-related behavior. It turned out that the psychotherapists mainly reported a good state of health although their reported state of health was more negative than in the general population with equal age and level of education. This finding is surely connected with specific mental, physical and existential burdens of their profession as well as with specifics of the “psychotherapist personality”. The psychotherapists’ evaluations highly depend on age, but not significantly on sociodemographical criteria like gender and place of establishment (East/West Germany). Also the affiliation to a therapy school (psychoanalysis, depth psychological funded psychotherapy, behavior therapy) is irrelevant for the subjective evaluation of one’s own health. Concerning the annual number of consultations and disability days the psychotherapists are clearly below average. They report a lot of attentiveness about their health and practice a health-benefical behavior. In this case they make higher demands on themselves than the general population. 相似文献