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991.
高原训练的生物学效应   总被引:1,自引:1,他引:1  
高原训练对人体有着复杂的生理学效应和训练学效应,是提高运动员运动能力的一种较好的赛前训练方法。对高原训练的起源及对人体呼吸、心血管、血液、骨骼肌、中枢神经等系统的影响进行了分析,为科学认识和实施高原训练提供参考。  相似文献   
992.
As society ages, there is an increasing demand for knowledge and skills to care for the elderly. Innovative ways to stimulate the interest of medical students in geriatric medicine present an important challenge to medical schools today. This article discusses the value of a student interest group in meeting this challenge. In 1988, the Department of Geriatrics at the Mount Sinai School of Medicine in New York City initiated a student interest group in geriatrics. Over the ensuing years, this group has provided medical students with a forum for pursuing research interests in geriatrics, networking with other students, and interacting with faculty role models interested in geriatric medicine.  相似文献   
993.
The effectiveness of noise of various intensities and frequencies in modulating the amplitude of the acoustic startle reflex was evaluated, as a preliminary test of the capacity of these noises to produce consistent and reliable fear-potentiated startle in rats. It was determined that bands of noise containing high frequencies (greater than 10 kHz) tend to unconditionally reduce acoustic startle responses, probably by masking the high-frequency startle-eliciting stimulus. Noise containing high frequencies produced reliable fear-potentiated startle only when its estimated unconditioned startle suppression was subtracted from the enhancement obtained after pairing it with footshocks. Noises devoid of high frequencies produced modest-unconditioned startle enhancements and the most robust and reliable fear-potentiated startle when they were paired with footshocks. A nonmonotonic relationship between training shock intensity and the level of fear-potentiated startle was also exhibited when a low-frequency noise was used as a conditioned stimulus, a finding consistent with previous studies in which a visual stimulus was used. Finally, a differential Pavlovian conditioning procedure indicated that rats could readily discriminate between two different low-frequency bands of noise. The outcome of these experiments indicates that it is easier to employ low-frequency bands of noise to obtain auditory fear-potentiated startle with high-frequency startle-eliciting stimuli.  相似文献   
994.
In this case study, we assessed academic functioning, service satisfaction, and needs of student veterans at a community college who had accessed the Veterans Health Administration (VHA) Student Veteran Health Program (SVHP) (n = 36). The SVHP provides outreach and behavioral health services directly on a large community college campus to overcome common barriers to engagement in mental health care (e.g., distance from a VA medical center). Academic difficulties that were most commonly reported were in the areas of retention of information, meeting deadlines, and cooperation with other students. Overall, the majority of student veterans who received services in the SVHP were satisfied (76.5%). Services targeting attention and concentration and utilization of educational benefits were highlighted as important by student veterans. This case study of VA services delivered within the community college setting provides important insights into how to design VA services to target the needs of student veterans. Specific recommendations for supporting student veterans on a community college campus are discussed.  相似文献   
995.
Aversive conditioning was studied in individual honeybees flying back and forth between the hive and the sill of an open laboratory window, where they took sucrose solution from a target so constructed that shock could be delivered while the proboscis was in contact with the solution. During feeding, a conditioned stimulus—substrate vibration or airstream—was paired with brief shock avoidable by interruption of feeding. In Experiment 1, unreinforced preexposure of the conditioned stimulus was found to retard acquisition (latent inhibition). In Experiment 2, which was designed to inquire into the stimulus specificity of the effect, differential conditioning was found to be impaired by unreinforced preexposure of the positive stimulus and facilitated by unreinforced preexposure of the negative stimulus. In Experiment 3, a summation experiment designed to test various alternative explanations of the effect, a preexposed stimulus was found to suppress response to an excitatory conditioned stimulus when the two stimuli were presented together.  相似文献   
996.
The bounded-input bounded-output stability, finite time stability and settling time of a single-loop feedback system consisting of a nonlinear time-varying gain followed by a linear time-invariant system are investigated via a nonlinear integral inequality. The gain has the form k0+k1(t)+k2(t)g(bd) where g(bd) is a monotonic increasing function. The system is bounded-input bounded-output stable provided the time-varying gains are L1(0, t8) functions and is finite time stable for bounded gains. The nonlinear integral inequality, which is used to obtain explicit and useful bounds on the output of the system, is also employed to determine the settling time.  相似文献   
997.
Findings are presented from the second phase of a UK longitudinal study of 33 gay father, 35 lesbian mother, and 43 heterosexual parent families when their adopted children reached early adolescence. Participants predominantly lived in urban/suburban areas and were mostly white and well-educated. Standardized interviews, observations, and questionnaires of parental mental health, parent–child relationships, and adolescent adjustment were administered to parents, children, and teachers between 2016 and 2018. There were few differences between family types. However, adjustment problems had increased in all family types, with better parenting quality and parental mental health associated with fewer adjustment problems. The findings contribute to adoption policy and practice, and to theoretical understanding of the role of parental gender in child development.  相似文献   
998.
In this article we review findings from a recent longitudinal study of the contribution of phonological working memory to vocabulary acquisition and reading development. A total of 80 children were tested initially at school entry at the age of four years, and were tested in three further waves at ages 5, 6, and 8 years. The results indicate that phonological memory skills constrain vocabulary growth during the first year or so in school but that subsequently, vocabulary knowledge is a pacemaker in the development relationship with memory. Phonological memory skill in prereading children was found to be significantly linked with scores on a reading test at age 8 which encourages the use of a phonological recoding strategy. The theoretical and practical implications of the findings, and important areas for future research, are discussed.  相似文献   
999.
Using nationally representative samples of 45,964 two‐ to nine‐year‐old children and their primary caregivers in 17 developing countries, this study examined the relations between children's cognitive, language, sensory, and motor disabilities and caregivers' use of discipline and violence. Primary caregivers reported on their child's disabilities and whether they or anyone in their household had used nonviolent discipline, psychological aggression, and physical violence toward the target child and believed that using corporal punishment is necessary. Logistic regression analyses supported the hypothesis that children with disabilities are treated more harshly than children without disabilities. The findings suggest that policies and interventions are needed to work toward the United Nations' goals of ensuring that children with disabilities are protected from abuse and violence.  相似文献   
1000.
成人教育与终身教育   总被引:1,自引:1,他引:1  
成人教育是普通教育的补充和延伸,有其自身特色,它又是终身教育的重要组成部分,实施终身教育必须依托成人教育。体育成人教育又是成人教育的有机成分之一。时代呼唤终身教育,社会需要成人教育,二者有其有内在联系,也存在区别。本文试图就成人教育、体育成人教育和终身教育的意义、作用及其关系作一简略述评。  相似文献   
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