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991.
992.
A McCollough effect was induced in subjects by having them view typical adapting stimuli binocularly for 5 min. In the control condition, the strength of the McCollough effect was measured 20 min after the end of the adaptation. The strength was measured during monocular and binocular viewing of a test pattern via a color cancellation technique. Monocular strengths for the two eyes of a given subject were equal to each other and slightly weaker than the binocular strength. In the test condition, 15 min of the 20 min between adaptation and testing were spent monocularly viewing black and white gratings of the same orientation and spatial frequency as the adapting gratings. The strength of the effect as measured ipsilaterally was markedly decreased from that in the control condition. The strength of the effect as measured with the contralateral eye showed only a small decrease from that of the control condition. This finding is relevant to various models of the McCollough effect and related color aftereffects, especially those that posit a “learning” type of mechanism between achromatic spatial channels (which exhibit clear interocular transfer of various achromatic effects) and monocular color channels.  相似文献   
993.
An electronic device for detecting movement in small animals is described. The principle involves assessing changes in resistance between pairs of grid bars in a cage. The device is inexpensive, sensitive to movement, easy to calibrate and install, reliable across different activity arenas, and indifferent to animal size.  相似文献   
994.
995.
The concepts of informed consent and surveillance of human research designed to protect human subjects is commendable. The regulations of the Institutional Review Board (IRB) are having a major impact on clinical cancer research. There is greater administrative time needed of the investigator, the mechanisms of patient care have become cumbersome and some patients reject optional medical management that could be life saving. IRB regulations must be flexible to meet the needs of human subjects as well as those of the clinical investigator.  相似文献   
996.
This article describes three kinds of information constraints in medical encounters that have not been discussed at length in the medical ethics literature: constraints from the concept of a disease, from the diffusion of medical innovation, and from withholding information. It describes how these limit the reliance rational people can justifiably put in their doctors, and even the reliance doctors can have on their own advice. It notes the implications of these constraints for the value of informed consent, identifies several procedural steps that could increase the value of the latter and improve diffusion of innovation, and argues that recognition of these constraints should lead us to devise protections which intrude on but can improve these encounters.  相似文献   
997.
A radiotelemetry system for continuous monitoring of the temperature and/or location of small animals is described. All the functions of system control are carried out by an on-line microcomputer (TRS-80 Model III), resulting in a versatile system capable of alternating recording the temperature/location of multiple subjects with other behavioral or physiological events, such as activity level. We describe the use of this system in monitoring body temperature in hamsters and in recording the incubation pattern of breeding ring doves.  相似文献   
998.
Prior surgical implantation of a venous catheter sensitized rats to coldimmobilization stress. Three of six catheterized females succumbed during the stress. The remaining rats fell into two groups in terms of their core temperature at the end of the stress period: Male uncatheterized rats had higher temperatures than rats in the other three groups. No relation was found between catheter patency and magnitude of hypothermia. Degree of gastric disease paralleled the core temperature findings in that the male uncatheterized rats had significantly fewer gastric erosions than the rats in the other three groups. Additionally, a robust effect of gender was found with uncatheterized females showing more hypothermia and more gastric disease than uncatheterized males. A subsequent experiment was conducted to evaluate whether anesthesia or wearing the protective spring was responsible in part for the sensitization seen. Here, the gender difference was less although females consistently averaged lower core temperatures after stress than did males. Despite similar core temperatures after stress, females that were prepared with the protective spring apparatus developed more gastric disease than female controls or similarly treated males. Thus, the additional sensitization exhibited by females in the first experiment may relate to the fact that both catheterization and the taping procedure were sensitizers while only catheterization was a sensitizer for males.  相似文献   
999.
1000.
D McDermott 《Adolescence》1984,19(73):89-97
The purpose of this study was to examine the relationship of two variables, parental drug use and parental attitude toward adolescent drug use, both as perceived by the adolescent respondent to his or her own use or nonuse of drugs. A sample of 106 drug-using and 96 nondrug-using adolescents was obtained through the use of the anthropological " snowball " technique. All respondents were administered a drug use history profile and a personal data questionnaire. In order to be classed as drug users, respondents had to have been using two or more recreational substances on a regular basis. Nondrug users were those who used no recreational drugs, although individuals who had tried alcohol or tobacco experimentally were included in this group. On the personal data form, respondents were asked to describe their parents' use of alcohol, tobacco, or other substances, and to indicate their parents' attitudes concerning adolescent use of drugs. Parental attitudes were classed as permissive if the respondent indicated that parents were indifferent about drug use, if they accepted a certain range of drugs, or if the decision were left up to the youth. A nonpermissive attitude was defined as one which would not accept drug use by the adolescent. Four 2 x 2 Chi-square analyses were used to determine significance of the relationship between adolescent drug use and parents' use or nonuse of drugs, parents' attitudes about adolescent use or nonuse and actual adolescent use or non-use, and this same attitudinal relationship looking at parent users and nonusers separately.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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