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71.
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
72.
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
73.
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
74.
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
75.
Shea MT Stout RL Yen S Pagano ME Skodol AE Morey LC Gunderson JG McGlashan TH Grilo CM Sanislow CA Bender DS Zanarini MC 《Journal of abnormal psychology》2004,113(4):499-508
In this study, the authors examined time-varying associations between schizotypal (STPD), borderline (BPD), avoidant (AVPD), or obsessive-compulsive (OCPD) personality disorders and co-occurring Axis I disorders in 544 adult participants from the Collaborative Longitudinal Personality Disorders Study. The authors tested predictions of specific longitudinal associations derived from a model of crosscutting psychobiological dimensions (L. J. Siever & K. L. Davis, 1991) with participants with the relevant Axis I disorders. The authors assessed participants at baseline and at 6-, 12-, and 24-month follow-up evaluations. BPD showed significant longitudinal associations with major depressive disorder and posttraumatic stress disorder. AVPD was significantly associated with anxiety disorders (specifically social phobia and obsessive-compulsive disorder). Two of the four personality disorders under examination (STPD and OCPD) showed little or no association with Axis I disorders. 相似文献
76.
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
77.
We present two experiments in which we measured lexical decision latencies and errors to words with few or many orthographic neighbors (ie., Coltheart's N). The main goal of the study was to examine whether or not the neighborhood size effect in a lexical decision task could be affected by the exposure duration of the stimulus item (unlimited vs. limited time exposure, 150 msec plus a backward mask) and the type of decision involved in the task (yes/no vs. go/no-go lexical decision tasks). In the yes/no task, the results showed a facilitative neighborhood size effect for low frequency that did not interact with exposure duration (Experiment 1). In contrast, in the go/no-go task (in this task, participants are instructed to respond as quickly as they can when a word is presented and not to respond if a nonword is presented), the neighborhood size effect for low-frequency words (and for nonwords) was greater under limited viewing time (Experiment 2). In addition, the word frequency effect was greater in the go/no-go task than in the yes/no task, replicating Hino and Lupker (1998, 2000). The results were interpreted in terms of the interaction of decision and lexical factors in visual-word recognition. 相似文献
78.
The present study examined the validity of a Spanish version of the Participation Motivation Inventory, modified for swimming by Gould, Feltz, and Weiss in 1985, and investigated whether young swimmers differing in sex and age vary in their objectives for participation. Swimmers (204 boys and 224 girls, ranging in age from 8 to 22 years) were administered the inventory. Factor analysis with varimax rotation identified seven factors fairly consistent with previous research. Differences were found across age and sex. Females placed greater emphasis than males on Friendship and Fun and indicated lower importance rating to Status. Younger children (8-10 years) rated Fun/Friendship, Competition/Skills, Significant Others, and Status significantly higher in importance than did the other age groups. 相似文献
79.
This study investigated amygdala-hippocampus's functional asymmetry in the emotional modulation of memory for stories. Thirty-nine, right-handed, drug-resistant epilepsy patients who had been submitted to unilateral temporal lobectomy (19 left and 20 right) watched either an arousing or neutral version of a story presented audio-visually. The slide sequence was the same in the neutral and arousing version, the narratives were matched for structure and comprehensibility. The set and order of the 11 slide sequence were identical in both conditions. Free recall and recognition measures were taken 2h after story presentation. Subjects in the TLE group who watched the arousing version recalled more details than the subjects who watched the neutral version (t(37)=3.4,p<.001). The group who watched the arousing version recalled more details of the phase 2 of the story (t(37)=6.76,p<.001). Scores in both conditions did not differ between control subjects and temporal lobectomy patients. When the right and left lesioned groups' results were analyzed separately, it was observed that the two groups did not differ in their recall of the neutral version. The right lesioned group recalled more items of the arousal than the neutral version (Z=-3.55,p<.001). However the left lesioned group did not show the memory enhancement for the emotional version, in this group it was only found an enhanced recall of the more pictorial emotional segment of the narrative (Z=-3.11,p<.001). This illustrates that the right amygdala can influence retention of complex emotional stimuli with verbal and pictorial arousing properties. We concluded that an intact left amygdala-hippocampus is important for enhancement of memory related to emotionally arousing verbal material. 相似文献
80.
The process of learning the structure of novel objects involves the selective use of information available in the distal stimulus. By allowing participants to explore the object within a limited field of view, we were able to examine more rigorously what regions of the object are actually selected in the learning process. Participants explored objects either by moving a circular aperture over a stationary novel object (the aperture-movement condition), or by moving the object behind a stationary aperture (the object-movement condition). Given the differences in how the spatial layout of object parts is revealed in the two study conditions, we expected that exploration would be more systematic in the aperture-movement condition than it would be in the object-movement condition, and would lead to better object recognition. We show evidence that in the aperture-movement condition exploration patterns were more related to the structure of the object and, as a consequence, the aperture-movement condition resulted in more accurate recognition in a later old--new discrimination test. 相似文献