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采用常规组织学方法观察和测量斯氏鼢鼠(Myospalax smithi)、棕色田鼠(Microtus mandarinus)和昆明种小白鼠(Mus musculus)(简称小鼠)肾脏的显微结构。结果表明:皮质与髓质的厚度比在三种鼠中有差异,其大小依次为:斯氏鼢鼠>棕色田鼠>小鼠;皮质迷路内近曲小管与远曲小管的数量比在三种鼠中也不相同,斯氏鼢鼠为1.92∶1,棕色田鼠为1.77∶1,小鼠为2.11∶1;三种鼠肾小囊腔的腔隙从小到大依次为:小鼠、棕色田鼠和斯氏鼢鼠。上述结果表明,小鼠肾脏重吸收能力大于棕色田鼠和斯氏鼢鼠,与它们的生境和食性密切相关。 相似文献
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考场作文需戴着镣铐跳舞。今年江西卷的作文命题限制性极强．除了要符合书信的格式要求外．还要符合书信的语体特征．如亲切自然．口语化。此外还要符合命题者提出的“为田鼠或田鼠的天敌代拟一封给人类的信”的要求．即要采用拟人的手法．符合田鼠或田鼠的天敌的口吻。这篇文章在这点上完全符合命题者的要求,语言亲切自然,拟人化手法运用贴切．文字间流淌着“构建一个和谐的、诗意的、全新的美好自然”的强烈愿望。 相似文献
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种群遗传结构是目前继种群生态学和行为生态之后研究的又一热点。布氏田鼠（Lasiopodomys brandtii）是我国内蒙古典型的草原害鼠和田鼠型鼠疫的主要宿主。近年来,气候变化和人类活动导致草原生态系统的逆向演替,在一些隔离区,布氏田鼠的栖息地遭到严重破坏,致使被隔离的种群受到严重的影响。深入了解布氏田鼠种群遗传结构将对研究布氏田鼠物种适应性、区域性成灾调控和治理以及预防控制田鼠型鼠疫具有重要意义。因此,本文就基于不同的分子标记对布氏田鼠种群遗传结构的研究进行简要综述。 相似文献
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情绪表达及其辨认是人际互动的第一步。为了探究识别情绪的影响因素,研究结果表明:1.情绪识别呈现心境一致性效应。高愉悦度的心理体验对情绪识别效果要好于低愉悦度的情绪识别,且差异达到显著性水平;2.情绪识别存在显著的性别差异。其中,无论男被试还是女被试,在识别女性表情时准确率都高,表明女性在情绪识别中存在自我性别偏见。男性的情绪识别存在反向的性别偏见;3.无论被试的性别、启动情绪如何变化,情绪识别在愤怒表情、恐惧表情上都存在显著差异。通过探讨在不同心理体验条件下情绪识别的差异研究,为提高情绪管理能力提供新思路。 相似文献
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一天,田鼠爸爸和田鼠妈妈带着小田鼠又去糟蹋粮食,结果被早已躲在边上的农夫用锄头剁死了。小田鼠由于身体小而幸免于难。小田鼠跌跌撞撞、惊魂未定地回到洞里时,沾满泥巴的身体已是青一块紫 相似文献
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New World primates face problems of communication distinct from those of their Old World counterparts. We suspected that the odor of urine might serve the function of communicating information among animals or troops. Two studies were conducted withSaimiri sciureus; one examined, in a laboratory enclosure, the influence of breeding season, social condition, area, and whether the urine was from known animals or from strangers, and the second measured, in a seminatural rain forest, responses to our spreadingSaimiri urine on selected sites. Enclosure and field produce the same general patterns of frequencies of behavior for urination, the urine wash and kick wash, and rubbing. The chief difference in behavior between the environments is found in the frequency of sneezing. Season (breeding or nonbreeding) is the most effective variable producing this general pattern: During the breeding season, males urine-wash throughout the enclosure or troop range, whereas during the nonbreeding season, this behavior is restricted in location, at least in the enclosure. At this time, females increase their frequencies of sniffing and rubbing. Many of these behaviors are observed only in special locations of the enclosure. The results show thatSaimiri respond differently to the urine of known and foreign animals, depending upon the season and whether they are with members of their own sex or both sexes. It is suggested that primates not equipped with specialized organs for scent marking may use urine opportunistically to communicate. 相似文献
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宋玮 《河北广播电视大学学报》2012,(1):77-79
普通话能力测试越来越受到社会的重视,在普通话的教学过程中,既要考虑学生的实际情况,帮助他们树立学好普通话的信心,同时通过多种教学方法和教学手段提高他们学习的兴趣,使其掌握正确的学习方法,再辅以普通话水平测试的促进作用,推动普通话教学的顺利进行和推普工作的可持续发展。 相似文献
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普通话是汉民族的共同语 ,地方普通话是介于地方方言和标准语普通话之间的一种过渡语 ,研究地方普通话对提高方言区人民普通话水平有很大帮助。本文从语音、词汇两方面分析了邢台地方普通话的语言特征 相似文献
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为考察普通话学习者是否具有自身声调范畴及具体的表现形式,对3名初级和3名中级普通话学习者进行发音实验及听辨实验,以被试听辨自己普通话声调的判定与实际声调是否一致作为标准。结果显示声调范畴感知没有阶段性差异。但有相对固定声调感知范畴者,一部分是因为本身发音和辨别音高变化的能力佳,其声调感知范畴与普通话声调范畴相似,另一部分采取了特定的感知策略,如通过音长、音强等声学特征辅助等。 相似文献
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Concentrations of sex hormones in umbilical-cord blood: their relation to sex and birth order of infants. 总被引：4，自引：0，他引：4
In 3 groups of human newborns, 5 sex hormones were assayed from samples of umbilical-cord blood, and concentrations were analyzed by the sex and birth order of the infants. The 5 hormones assayed were testosterone, androstenedione, estrone, estradiol, and progesterone. Concentrations of testosterone were significantly greater in males than females. The other 4 hormones did not differ significantly by sex. In both sexes, firstborns had significantly more progesterone and estrogens, with progesterone showing the largest birth-order effects. Among male infants, firstborns had higher concentrations of testosterone. The higher concentrations of progesterone in firstborns of both sexes, and of testosterone in firstborn boys, were found not to be due to length of labor, birth weight, or maternal age. However, they were a function of temporal spacing of childbirths. Later borns who were closely spaced in relation to their next-older siblings had lower concentrations of hormones. The effect of temporal separation was greater on male than female infants for each of the 5 hormones studied. The results are discussed in terms of the possible effects of hormone "depletion" on the psychological development of closely spaced later borns. 相似文献
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Mary Vakali 《European Journal of Psychology of Education - EJPE》1991,6(3):325-336
The present research aimed to study how children identify and produce various types of clock time on pictures of analogue display and whether the use of digital watches makes a difference in their performance on the identification and production tasks. Over one hundred (129) 7–10 year-old children of both sexes were tested under two different conditions. In the first condition the subjects were expected to write down the exact times as shown by pictures of analogue clock faces. In the second condition they had to draw two lines — a short one for the hour hand and a longer one for the minute hand — on pictures of analogue display, in order to match the relevant times, which were provided by written questions. Statistical analysis of correct responses showed that clock time production is more difficult than clock time identification. Hours past are handled more easily, as to both identification and production, than hours to. Whole hour and quarter past times are easier than half past times. The acquisition of clock time knowledge improves with age. However, sex does not affect performance. The qualitative analysis of errors has yielded a variety of error categories. It has also shown the deviations produced by the use of digital watches in the identification and production of clock time on analogue clock faces. 相似文献
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许悦 《福建师大福清分校学报》2005,(3):22-25
知识女性成才问题,已成为当今重要的研究课题.本文从女性的自然性别差异的特殊性、社会性别的角色定位、传统性别的角色分工、社会评价标准的导向作用和社会机会的不均等等方面探讨知识女性成才的障碍,并为创造健康良好的知识女性成才的外部环境,进一步促进知识女性潜能的充分发挥提出了相应的对策. 相似文献
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普通话水平测试员应具有的素质 总被引：1，自引：0，他引：1
普通话水平测试是新时期推普工作的重大举措，担任主要测试工作的测试员肩负着这一重任，如何全面提高测试队伍的测试水平，增强测试员自身的素质是保征这一举措实施的关键。依据在测试工作中的深刻体会和思考，对普通话测试员应具有的专业素质和政治素质进行评述。 相似文献
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黔东方言,总体上说都属于西南官话,但内部有差异。到底有何差异,语音上的分区常常显得不得要领,而利用方言特征词,能为区分方言与方言之间的差异提供较为可行和较为科学的依据,弥补历来凭借语音标准区分差异的不足。 相似文献
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Sarah A. Sloane Sandra L. Shea Melissa Miley Procter Donald A. Dewsbury 《Learning & behavior》1978,6(2):244-248
A total of 200 muroid rodents, 20 from each of 10 species from diverse ecological adaptations, were tested for depth perception near the age of weaning. Each animal was given 10 trials in a visual cliff. Seven of the 10 species, Israeli gerbils, California voles, house mice, meadow voles, cactus mice, cotton mice, and deer mice, showed some evidence of depth discrimination. By contrast, white-footed mice, prairie voles, and montane voles showed no evidence of such discriminative ability. Although there was no strong relationship apparent between the usual habitat of the species and their tendency to choose the shallow side in the visual cliff, a relationship was found among ecological factors, open-field behavior, and the latency to make a descent from the centerboard of the visual cliff. 相似文献