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41.
Between 1993 and 2002, 39 clinical trial staff were investigated for scientific misconduct by the Office of Research Integrity
(ORI). Analysis of ORI case records reveals practices regarding workload, training and supervision that enable misconduct.
Considering the potential effects on human subjects protection, quality and reliability of data, and the trustworthiness of
the clinical research enterprise, regulations or guidance on use of clinical trial staff ought to be available. Current ORI
regulations do not hold investigators or institutions responsible for supervision and training of clinical trial staff. Given
the important issues at stake, the definition of research misconduct should encompass the intentional or negligent mismanagement
of scientific projects. Individual institutions and professional associations not only can but should adopt stricter standards
of conduct than those reflected in federal regulations. 相似文献
42.
The ordinary long-term rod and cone dark-adaptation curves have generally been assumed to follow a single exponential rate of recovery. However, in two previous papers on rod dark-adaptation (Stabell et al., 1986a, b), the recovery curve was found to consist of three different sections. The results of the present paper show the same type of recovery function with three different sections for the long-term dark-adaptation curve of the long-wave cone system. During the major, middle section log cone threshold, like log rod threshold, is linearly related to the logarithm of the concentration of bleached photopigment. Presupposing that the bleached cone photopigment acts as a ligand, the change in threshold level obtained during the middle section of the dark-adaptation curve is well described by the change in activity rate of an allosteric, postively cooperative enzyme built as a dimer. 相似文献
43.
RAGNAR J. VÆRNES GUNNAR KNUDSEN ARVID PÅSCHE INGVAR EIDE ASBJØRN AAKVAAG 《Scandinavian journal of psychology》1988,29(2):111-122
An experimental study was set up simulating the environmental conditions and work load among drillers and maintenance personnel offshore. Thirty-six male subjects participated in the experimental study involving 3h exposures with dry gloves, wet gloves or without gloves. The subjects were working on tasks involving heavy and light muscle work, dexterity and cognitive tasks. Body and skin temperatures and heart rate variability were continuously monitored. Neuropsychological and endocrinological parameters were intermittently monitored. The data from the work performance tasks showed that motor functions, both gross and fine, were impaired when working with wet and, especially, without gloves. Working without gloves also affected mental work tasks. The neuropsychological and physiological data confirmed the work task studies: working with wet or without gloves led to increased tremor and impaired finger dexterity. Furthermore, reasoning was consistently impaired throughout the exposures compared with working with dry gloves. The heart-rate variability data and the endocrine results also showed a significant central nervous stress reaction for the two hypothermic conditions compared with the dry glove condition. Especially for drilling further north these data should imply that both health and performance may be detrimentally affected during working under such conditions with insufficient thermal protection. 相似文献
44.
BJØRN KILLINGMO 《Scandinavian journal of psychology》1985,26(1):53-62
In two articles the controversial situation within contemporary psychoanalytic theory is discussed with reference to both the form and content of the theory. In the first article some areas of theoretical conflict between traditional drive theory, on the one hand, and object relations theory, self theory, and ego theory, on the other, are surveyed. It is concluded that inconsistency and ambiguity seem so penetrating that one can hardly speak of a unified theory of psychoanalysis at present. This seems to be a new situation in the history of psychoanalysis. A main issue of disagreement is that between drive theory and object relations theory concerning the nature of human motivation. In order to bridge the theoretical gap between the two positions, it seems necessary for psychoanalysis to disclaim the monolithic status of the drives and to adopt a broad theory of motivation where drives are only one contribution among several types of motivating forces. In the second article some lines of advance in psychoanalytic theory are discussed. 相似文献
45.
The purpose of the present study was to investigate the stability of memory and information processing in schizophrenics and affectively disturbed patients. Twenty-two schizophrenics, eight affectives and 14 normal controls were tested twice, with an interval of approximately one year. Results showed that normals performed better than schizophrenics and affectively disturbed patients on almost all of the cognitive measures. The differences reached a level of significance on a reaction time test, a vigilance task and a long-term memory task. The only measure where the difference did not reach a level of significance was on a short-term memory test. Groups' performance to some extent changed over time on most of the measures, but the changes were not significantly different for different groups. 相似文献
46.
Using a Wright colorimeter the ordinary long-term, long-wave cone dark-adaptation curve was measured at 0, 2, 4, 7, 17, 25, 40 and 49 degrees nasally in the visual field. In opposition to previous findings, the results show that the dark-adaptation function of the long-wave cones changes markedly when the test field is moved outward from the rod-free fovea. It is suggested that the kinetics of the long-wave cone photopigment change with eccentricity. Also, at variance with previous findings, the present curves at all eccentricities may reasonably well be interpreted as consisting of three different sections; a first section where the threshold decreases rapidly, followed by a major, approximately linear section and a terminating section that converges asymptotically towards the final level of sensitivity. This finding suggests that the dark-adaptation process of the cone system, under the given experimental conditions, is based on three somewhat different processes. 相似文献
47.
Following substantial bleaches, the specific form and hue thresholds were measured during dark adaptation with a test stimulus of 1 x 2 degrees at 40 degrees extrafoveally. The wavelength of the test field was varied between runs. The results show that both thresholds started to rise at about the cone-rod break of the dark-adaptation curve, irrespective of wavelength used in the test. Furthermore, the specific threshold for form was found to rise when a scotopic stimulus was superimposed on a photopic test flash. On the other hand, both thresholds remained at the cone-plateau level when the test flash was confined within the rod-free fovea. In order to explain the rise in the specific thresholds, it is suggested that signals from rods generated directly in response to the test stimulus may suppress both cone-mediated form and colour. It is also suggested that this type of rod-cone interaction represents a general characteristic involved in several kinds of visual information processing. 相似文献
48.
Stabell, B. & Stabell, U. Chromatic rod vision. VII. Intensity of pre-stimulation varied. Scand. J. Psychol., 1973, 14, 12–15.-Change in scotopic hue with variation of intensity of pre-stimulation was predicted on the basis of Hering's opponent theory of color, but the experimental results could not be adequately explained within the framework of the theory. 相似文献
49.
William C. Stebbins Robert N. Lanson 《Journal of the experimental analysis of behavior》1962,5(3):299-304
Four Ss were trained to press and hold down a telegraph key in the presence of a light. Subsequent release of the key during a tone was followed by water reinforcement. The schedule of reinforcement for key release was varied, and its effects on the latency (RT) of key release to the tone were studied. Both median RT and variability of RT were found to be inversely related to frequency of reinforcement as determined by the schedule. 相似文献
50.
Recent evidence strongly suggests that the relationship between threshold elevation ( T ) and fraction of bleached rhodopsin ( B ), obtained during a major, middle period of long-term rod dark adaptation in man, is well described by a power function, i. e., T = k · Bn , where k is a multiplicative constant and n is the exponent. Due primarily to the low reliability of measurements of rhodopsin regeneration, however, the exponent n of the power function cannot, at present, be given an exact value. Available information indicates that the value of the exponent ranges between 2.4 and 4. Implications of this uncertainty are discussed within the framework of the allosteric, tetrameric model of rod dark adaptation. It is concluded that this model in its simplest form may only offer a first approximation of the real system implicated in the process. 相似文献