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111.
Xenotransplantation, or the use of animal cells, tissues and organs for humans, has been promoted as an important solution to the worldwide shortage of organs. While scientific studies continue to be done to address problems of rejection and the possibility of animal-to-human virus transfer, socio-ethical and legal questions have also been raised around informed consent, life-long monitoring, animal welfare and animal rights, and appropriate regulatory practices. Many calls have also been made to consult publics before policy decisions are made. This paper describes the Canadian public consultation process on xenotransplantation carried out by the Canadian Public Health Association in an arm’s length process from Health Canada, the ministry overseeing government health policy and regulation. Focusing on six citizen fora conducted around the country patterned after the citizen jury deliberative approach, the paper describes the citizen panelists’ recommendations to hold off on proceeding with clinical trials and the rationales behind this recommendation. The consultation process is discussed in the context of constructive technology assessment, a framework which argues for broader input into earlier stages of technology innovation, particularly at the technology design stage. This study was supported by a grant to the first author from the Social Sciences and Humanities Research Council in Canada.  相似文献   
112.
In the current controversy about the value of transgenic crops, matters open to empirical inquiry are centrally at issue. One such matter is a key premise in a common argument (that I summarize) that transgenic crops should be considered to have universal value. The premise is that there are no alternative forms of agriculture available to enable the production of sufficient food to feed the world. The proponents of agroecology challenge it, claiming that agroecology provides an alternative, and they deny the claim that it is well founded on empirical evidence. It is, therefore, a matter of both social and scientific importance that this premise and the criticisms of it be investigated rigorously and empirically, so that the benefits and disadvantages of transgenic-intensive agriculture and agroecology can be compared in a reliable way. Conducting adequate investigation about the potential contribution of agroecology requires that the cultural conditions of its practice (and, thus, of the practices and movements of small-scale farmers in the "third world") be strengthened--and this puts the interests of investigation into tension with the socio-economic interests driving the development of transgenics. General issues about relationship between ethical argument and empirical (scientific) investigation are raised throughout the article.  相似文献   
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In 2 experiments, German-speaking dyslexic children (9-year-olds) showed impaired learning of new phonological forms (pseudonames) in a variety of visual-verbal learning tasks. The dyslexic deficit was also found when phonological retrieval cues were provided and when the to-be-learned pseudonames were presented in spoken as well as printed form. However, the dyslexic children showed no name-learning deficit when short, familiar words were used and they also had no difficulty with immediate repetition of the pseudowords. The dyslexic children's difficulty in learning new phonological forms was associated with pseudoword-repetition and naming-speed deficits assessed at the beginning of school, but not with phonological awareness and visual-motor impairments. We propose that the difficulty in learning new phonological forms may affect reading and spelling acquisition via impaired storage of new phonological forms, which serve as phonological underpinnings of the letter patterns of words or parts of words.  相似文献   
116.
The authors used a daily diary methodology to examine over 60 days how the within-person associations among event stress, alcohol consumption, and desire to drink varied as a function of gender, positive and negative alcohol-outcome expectancies, and avoidant coping in a sample of 88 regular drinkers. Multilevel regression analyses indicated that men who more strongly anticipated positive outcomes or a sense of carelessness from drinking drank relatively more on stressful days compared with low-stress days. Similar results were found predicting desire to drink. Men who anticipated greater impairment from drinking drank relatively less on stressful days. In general, these effects did not hold for women. Little evidence was found for the predicted effects for avoidant coping style, and some results showed that avoidant coping style buffered the exacerbating effects of careless unconcern expectancies.  相似文献   
117.
Photic Feedback treatment of a patient diagnosed with Miller Fisher syndrome has resulted in the rapid and permanent remission of symptoms. During Photic Feedback treatment, the CD20 appeared to be slightly increased. This may have been associated with changes in humoral immunity. The present clinical observation of a single patient suggests that Photic Feedback treatment should be investigated as a possible adjunct therapy for patients who suffer from polyneuropathies, such as Miller Fisher syndrome, within a carefully controlled clinical trial.  相似文献   
118.
The present study investigated the readiness potential (RP) preceding a brisk extension of the right middle finger during different arousal states as monitored by skin potential level (SPL). The late component of the readiness potential in the medium arousal state was significantly larger than those in the low and high arousal states. This finding indicates that the RP waveform may vary as a function of arousal states, suggesting the inverse U-shaped relationship proposed in studies of the contingent negative variation.  相似文献   
119.
This paper reports a series of experiments of the perceived position of the hand in egocentric space. The experiments focused on the bias in the proprioceptively perceived position of the hand at a series of locations spanning the midline from left to right. Perceived position was tested in a matching paradigm, in which subjects indicated the perceived position of a target, which could have been either a visual stimulus or their own fingertip, by placing the index finger of the other hand in the corresponding location on the other side of a fixed surface. Both the constant error, or bias, and the variable error, or consistency of matching attempts, were measured. Experiment 1 showed that (1) there is a far-left advantage in matching tasks, such that errors in perceived position are significantly lower in extreme-left positions than in extreme-right positions, and (2) there is a strong hand-bias effect in the absence of vision, such that the perceived positions of the left and right index fingertips held in the same actual target position in fact differ significantly. Experiments 2 and 3 demonstrated that this hand-bias effect is genuinely due to errors in the perceived position of the matched hand, and not to the attempt at matching it with the other hand. These results suggest that there is no unifying representation of egocentric, proprioceptive space. Rather, separate representations appear to be maintained for each effector. The bias of these representations may reflect the motor function of that effector.  相似文献   
120.
Backward-masking functions have been hitherto categorized into two types, commonly named Type A and Type B. The analysis of a model of Retino-Cortical Dynamics produces the prediction that spatially localized stimuli should reveal an oscillatory metacontrast function. The predicted new type of metacontrast masking function was investigated in a psychophysical experiment. The results show oscillatory metacontrast functions with significant power in the gamma range (30-70 Hz). A marked decrease in the oscillations is observed when the spatial extent of the stimuli is increased. The theoretical basis of the study relates the oscillations found in the metacontrast function to gamma-range oscillations observed in scalp and intracerebral recordings. The qualitative agreement between the model and data provides support for this putative relationship.  相似文献   
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