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141.
The concept of informed consent was one of the most fruitful ideas that deeply changed the relationships between physicians
and their patients from paternalism to respect for the personal autonomy of subjects needing professional medical care. The
great progress in medicine, also involving the pharmaceutical industry, has created an increasing need to perform different
clinical and experimental trials. The evolution of clinical research in the last decades has influenced strongly the design
of these studies. One of the most important changes in this field has been the use of placebo groups in double-blind controlled
studies. The controversies have involved not only the use of placebo when standard or proven treatment was available, but
also some specific problems concerning the procedure of obtaining informed consent in such trials. This paper briefly presents
the evolution of informed consent in Poland as well as different ethical and legal problems concerning informed consent and
the use of placebo controls in clinical trials.
An earlier version of this paper was presented at an international conference, “Placebo: Its Action and Place in Health Research
Today,” held in Warsaw, Poland on 12–13 April, 2003. 相似文献
142.
Yago E Duarte A Wong T Barceló F Knight RT 《Cognitive, affective & behavioral neuroscience》2004,4(4):609-617
Single-unit, event-related potential (ERP), and neuroimaging studies have implicated the prefrontal cortex (PFC) in top-down
control of attention and working memory. We conducted an experiment in patients with unilateral PFC damage (n=8) to assess the temporal kinetics of PFC-extrastriate interactions during visual attention. Subjects alternated attention
between the left and the right hemifields in successive runs while they detected target stimuli embedded in streams of repetitive
task-irrelevant stimuli (standards). The design enabled us to examine tonic (spatial selection) and phasic (feature selection)
PFC-extrastriate interactions. PFC damage impaired performance in the visual field contralateral to lesions, as manifested
by both larger reaction times and error rates. Assessment of the extrastriate P1 ERP revealed that the PFC exerts a tonic
(spatial selection) excitatory input to the ipsilateral extrastriate cortex as early as 100 msec post stimulus delivery. The
PFC exerts a second phasic (feature selection) excitatory extrastriate modulation from 180 to 300 msec, as evidenced by reductions
in selection negativity after damage. Finally, reductions of the N2 ERP to target stimuli supports the notion that the PFC
exerts a third phasic (target selection) signal necessary for successful template matching during postselection analysis of
target features. The results provide electrophysiological evidence of three distinct tonic and phasic PFC inputs to the extrastriate
cortex in the initial few hundred milliseconds of stimulus processing. Damage to this network appears to underlie the pervasive
deficits in attention observed in patients with prefrontal lesions. 相似文献
143.
Prey might assess that risk level estimated in the first encounter with a predator was fixed in subsequent responses, whereas prey using flexible behavior would track short-term changes in risk. The authors examined, in the field, refuge use of Iberian rock lizards (Lacerta monticola) after simulated predator attacks and tested (a) how risk was assessed when multiple sources of risk were present simultaneously, (b) how short-term changes in risk level of successive attacks affected refuge use, and (c) whether the interval between attacks was important, insofar as attacks were considered to be coming from the same or different predators. Results suggest that lizards have a flexible estimate of risk that is based on multiple sources and flexibly dependent on previous estimates. 相似文献
144.
López SR Nelson Hipke K Polo AJ Jenkins JH Karno M Vaughn C Snyder KS 《Journal of abnormal psychology》2004,113(3):428-439
The authors examined the role of family factors and the course of schizophrenia by carrying out additional assessments and analyses in 2 previously published studies of Mexican American and Anglo American patients and families. The authors found partial support for an attributional model of relapse for families who are low in emotional overinvolvement. Attributions of control, criticism, and warmth together marginally predicted relapse. The data also indicated that for Mexican Americans, family warmth is a significant protective factor, whereas for Anglo Americans, family criticism is a significant risk factor. These findings suggest that the sociocultural context shapes the pathways by which family processes are related to the course of illness. Moreover, the warmth findings suggest that families may contribute to preventing relapse. 相似文献
145.
Schmitt DP Alcalay L Allik J Angleitner A Ault L Austers I Bennett KL Bianchi G Boholst F Borg Cunen MA Braeckman J Brainerd EG Caral LG Caron G Casullo MM Cunningham M Daibo I De Backer C De Souza E Diaz-Loving R Diniz G Durkin K Echegaray M Eremsoy E Euler HA Falzon R Fisher ML Foley D Fry DP Fry S Ghayur MA Golden DL Grammer K Grimaldi L Halberstadt J Haque S Herrera D Hertel J Hoffmann H Hooper D Hradilekova Z Hudek-Kene-evi J Jaafar J Jankauskaite M Kabangu-Stahel H Kardum I Khoury B 《Journal of personality and social psychology》2004,86(4):560-584
146.
Freyd and Tversky's [Am. J. Psychol. 97 (1984) 109] data suggested that human observers tend to overestimate relatively high levels of symmetry (symmetry effect), and tend to underestimate relatively low levels of symmetry (asymmetry effect). However, on the basis of their holographic approach to visual regularity, van der Helm and Leeuwenberg [Psychol. Rev. 103(3) (1996) 429] predicted that, at any level of symmetry, both symmetry and asymmetry effects may occur as a consequence of correct estimates of symmetry-to-noise ratios. This prediction was tested in two experiments, with tasks and stimuli similar to those in Freyd and Tversky's study. First, subjects had to judge whether a noisy symmetry is more similar to a slightly more symmetrical variant or to a slightly less symmetrical variant. Second, for every pair of stimuli in such a triadic comparison, subjects had to judge which stimulus is the more symmetrical one. The results from both experiments show that the occurrence of (a)symmetry effects indeed depends on symmetry-to-noise ratios. 相似文献
147.
The authors examined anticipation in tool use, focusing on tool length and tool-use posture. Adults (9 women and 9 men in each experiment) held a rod (length 0.4-0.8 m), with the tip upward; walked toward a cube; chose a place to stop; and displaced the cube with the rod's tip. In 2 experiments, rod length, mass, and mass distribution, and the size of the cube were manipulated. Chosen distance depended on rod length and cube size. Because effects of cube size on distance resulted only from postural changes related to required control, distance anticipated displacement posture. A postural synergy comprising legs and trunk provided a stable platform for the displacement. An arm synergy was less extended for small cubes, longer rods, and handle-weighted rods. Selected distance anticipated those postures. 相似文献
148.
Jiří Adámek 《Studia Logica》2004,78(1-2):7-33
Finitary quasivarieties are characterized categorically by the existence of colimits and of an abstractly finite, regularly projective regular generator G. Analogously, infinitary quasivarieties are characterized: one drops the assumption that G be abstractly finite. For (finitary) varieties the characterization is similar: the regular generator is assumed to be exactly projective, i.e., hom(G, –) is an exact functor. These results sharpen the classical characterization theorems of Lawvere, Isbell and other authors.Supported by the Czech Grant Agency (Project 201/02/0148).Special issue of Studia Logica: Algebraic Theory of Quasivarieties Presented by
M. E. Adams, K. V. Adaricheva, W. Dziobiak, and A. V. Kravchenko 相似文献
149.
The aim of this study was to explore the psychological consequences of two earthquakes in Iceland in two probability samples of subjects--residents in the exposed area and a control group from an unexposed area. The sample was composed of 52 adults exposed to the earthquakes and 29 adults in a control group. Three months after the earthquakes, both groups were approached with questions from a survey consisting of the Harvard Trauma Questionnaire (HTQ), the Trauma Symptom Checklist (TSC), the Coping Styles Questionnaire (CSQ), the World Assumption Scale (WAS), and the Crisis Support Scale (CSS). The results revealed that 24% in the exposed group had Posttraumatic Stress Disorder (PTSD), and none in the control group had PTSD. Earthquake-related anxiety, inability to express one's thoughts and feelings, and emotional coping predicted 81% of the HTQ variance for both groups. Previous life events, low self-worth, and luck attributions, together with numbing and the feeling of being let down, predicted 56% of the symptom variance for both groups. When degree of traumatization and emotional coping were added to the model, another 30% of the variance could be explained. 相似文献
150.
Hugo?WesterlundEmail author Anna?Bergstr?m T?res?Theorell 《Integrative psychological & behavioral science》2004,39(1):3-15
Thirty-two female participants in a mobilising labour market programme offering temporary, alternative employment in Sweden
were followed longitudinally for one year, including a six month post participation follow-up period. It can be hypothesised
that an important aspect of the physiological effects of unemployment is a change in the balance between anabolic and catabolic
activities in the body and that re-employment should lead to a shift towards anabolism. An earlier study of a smaller subset
of the data, however, including both men and women, showed increased prolactin and decreased dehydroepiadrosterone sulphate
(DHEA-s) levels, contrary to the initial hypothesis. In the present analysis, intended to elucidate these results, psychophysiological
data were summarised in two indices, one connected with anabolism (made up of testosterone and DHEA-s) and one with catabolism
(prolactin, γ-glutamyl transferase, aspartate amino transferase, α levuline amino transferase, and body mass index). In addition,
self-rated anxiety, depression, hopelessness and personal control were analysed. The results indicate that the effect of ‘better’
activities within the programme was a temporary increase in anabolism, possibly indicating lower stress levels, and the effect
of ‘worse’ activities, on the one hand, a temporary decrease in the catabolic index, probably reflecting repressed alcohol
consumption, and, on the other hand, impaired anabolism. There was also a general but transient decrease in depressiveness
measured by the Hospital Anxiety and Depression Scale. The results seem to imply that it is difficult to achieve lasting effects
through a relatively short participation in a mobilising programme. 相似文献