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71.
宋人刘斧的《青琐高议》是一本极有价值的书:首先是它的辑佚补遗价值;二是作家作品研究之资料价值;三是弥补诗话(词话)或阙的价值;四是史料价值;五是为许多小说、戏曲提供原始材料的价值。但由于孔子以来所提倡之"不语怪、力、乱、神"偏颇认识的影响,从宋而降,一直被斥之为"荒怪"和"低俗"。其实,《青琐高议》中那些描写鬼神怪异之事,虽幻诞诡奇,而质实素朴,成为《聊斋志异》之先河,是文学艺术新异手法之先驱探索者。  相似文献   
72.
《苕溪渔隐丛话》是宋代三大诗话总集之一,《岁寒堂诗话》是宋代三大诗话别集之一。二书的诗学观不无相合之处:论诗崇尚诗骚、汉魏,称道渊明;高度肯定李、杜、韩、白等人之诗;肯定宋四家的转益多师。但其差异性更是显而易见:胡仔论诗兼取唐宋,认为诗歌代有才人,肯定了宋诗的成就及新变精神;张戒论诗宗唐黜宋,认为诗以代降,代不如人。尤其是对苏、黄的批评,前者体大包容,后者精深激切。二人对宋诗的健康发展都功不可没。  相似文献   
73.
利用H1(Rn)的原子分解理论以及h1(Rn)(局部Hardy空间)的分子理论,证明了一类奇异积分算子从H1(Rn)到h1(Rn)有界.作为应用,得到了若A′∈L (R1),则Cauchy积分算子CA从H1(R1)到h1(R1)有界.  相似文献   
74.
钱南扬先生的《〈宦门子弟错立身〉校注》对《宦门子弟错立身》中的生字难词、戏剧术语和方言俚俗语等详加解释,多所创发,但是仍然存在一些缺陷。文章主要讨论《〈宦门子弟错立身〉校注》中"敷演"、"却"和"且"的词语释义问题。  相似文献   
75.
钮树玉为人笃志好古,不为科举之业,精研文字、声音、训诂之学,为清代著名的《说文》学家。其研究《说文》的代表作为《说文解字校录》、《段氏说文注订》及《说文新附考》,分别涉及校勘、订段及新附字研究。由于前人对钮氏的著作尚未进行全面深入的研究,故对其在《说文》学史上的地位重视不够。整理钮氏的《说文》研究,对《说文》学史的建设具有重要的意义。  相似文献   
76.
Known as the ‘third polar region’, the Qinghai-Tibet Plateau represents one of the harshest highland environments in the world and yet a number of organisms thrive there. Previous studies of birds, animals and humans have focused on well-differentiated populations in later stages of phenotypic divergence. The adaptive processes during the initial phase of highland adaptation remain poorly understood. We studied a human commensal, the Eurasian Tree Sparrow, which has followed human agriculture to the Qinghai-Tibet Plateau. Despite strong phenotypic differentiation at multiple levels, in particular in muscle-related phenotypes, highland and lowland populations show shallow genomic divergence and the colonization event occurred within the past few thousand years. In a one-month acclimation experiment investigating phenotypic plasticity, we exposed adult lowland tree sparrows to a hypoxic environment and did not observe muscle changes. Through population genetic analyses, we identified a signature of polygenic adaptation, whereby shifts in allele frequencies are spread across multiple loci, many of which are associated with muscle-related processes. Our results reveal a case of positive selection in which polygenic adaptation appears to drive rapid phenotypic evolution, shedding light on early stages of adaptive evolution to a novel environment.  相似文献   
77.
78.
Aim was to identify critical load (CL) in young and elderly apparently healthy male cohorts. To contrast the metabolic, cardiovascular and perceptual responses on CL according to age. We evaluated 12 young (23 ± 3 years) and 10 elderly (70 ± 2 years) apparently healthy active males, who underwent: (1) 1 repetition maximum (1RM) test on a 45° Leg Press; (2) on different days, three high-intensity resistance exercise constant load tests (60%, 75% and 90% 1RM) until fatigue (Tlim). Absolute values of both the CL asymptote and curvature constant (kg) were significantly lower in elderly subjects (P < 0.05). In contrast, elderly subjects demonstrated a significantly higher number of repetitions at CL when compared with young subjects (P < 0.05). As expected, oxygen uptake (VO2) and heart rate (HR) during maximal aerobic exercise testing were significantly reduced in older subjects. However, percent-predicted aerobic capacity were higher in older subjects (P < 0.05). In addition, blood lactate ([La?]) corrected to Tlim and rating of perceived exertion values were greater in younger subjects at all intensities (P < 0.05). These findings, despite reduced force production in older subjects, endurance-related parameters are well preserved according to age-adjusted percent-predicted values in apparently healthy males.  相似文献   
79.
We investigated combined effects of ambient temperature (23°C or 13°C) and fraction of inspired oxygen (21%O2 or 13%O2) on energy cost of walking (Cw: J·kg?1·km?1) and economical speed (ES). Eighteen healthy young adults (11 males, seven females) walked at seven speeds from 0.67 to 1.67 m s?1 (four min per stage). Environmental conditions were set; thermoneutral (N: 23°C) with normoxia (N: 21%O2) = NN; 23°C (N) with hypoxia (H: 13%O2) = NH; cool (C: 13°C) with 21%O2 (N) = CN, and 13°C (C) with 13%O2 (H) = CH. Muscle deoxygenation (HHb) and tissue O2 saturation (StO2) were measured at tibialis anterior. We found a significantly slower ES in NH (1.289 ± 0.091 m s?1) and CH (1.275 ± 0.099 m s?1) than in NN (1.334 ± 0.112 m s?1) and CN (1.332 ± 0.104 m s?1). Changes in HHb and StO2 were related to the ES. These results suggested that the combined effects (exposure to hypoxia and cool) is nearly equal to exposure to hypoxia and cool individually. Specifically, acute moderate hypoxia slowed the ES by approx. 4%, but acute cool environment did not affect the ES. Further, HHb and StO2 may partly account for an individual ES.  相似文献   
80.
我国多数男生引体向上得"零"分,使上肢力量测评出现"地板效应"。采用量化研究和质性研究两种范式提高研究效度。量化研究对学生体质与健康调研数据和监测数据进行方差分析、多重比较和回归分析,结果表明:(1)每5~10年,男生的握力、体重、身高、BMI、引体向上均值差异显著;(2)年龄、握力、体重、身高、BMI分别显著预测引体向上成绩,体重和握力是影响我国男生引体向上成绩的主要影响因素。质性研究结果表明,引体向上"零"分主要有四个方面的原因:体重增长难挡,力量增长受限,个体认知偏差,社会支持薄弱。结论:我国男生引体向上"零"分的首要原因是体重增长较快,其次,主要肌群绝对力量和耐力增长不足,男生对引体向上的认知有偏差,学校、家长、社会支持较弱;借助政策控制体重、发展肌力、完善测评标准、促进男生积极练习引体向上十分重要。  相似文献   
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