听觉剥夺对成年雄性斑胸草雀鸣唱行为和LMAN核团的影响

对成年雄性斑胸草雀听觉剥夺引起鸣曲声谱结构和音节参数的变化进行分析,利用焦油紫染色等方法,检测了听觉剥夺对LMAN核团平均面积、体积和核团内的细胞面密度的影响。成年雄性斑胸草雀致聋后14 d,声谱结构出现畸变,音节的熵值和熵值变异数均发生显著变化,表明斑胸草雀成年后稳定的鸣曲需要听觉反馈来维持,失去听觉导致致聋鸟变成聋哑鸟。同时LMAN核团的平均面积和体积有明显减小的趋势,LMAN核团内的细胞面密度下降,说明了致聋导致鸣唱行为的畸变,可能与致聋所导致其脑内发声学习通路中的输出核团-LMAN核团退化有关,该结果为探究LMAN核团在鸣禽发声系统中的功能和揭示致聋后聋哑变化可能的机理提供了理论参考。     

界面核和高级发声中枢与鸣禽鸣曲的学习和维持

鸣禽鸣唱和人类语言都是经过后天学习而获得的。幼鸟在学习鸣唱时先记住教习曲模板，再通过发声反馈比较自鸣曲和模板并调整发声输出，成年后同样需要听觉反馈来维持自鸣曲的特征和稳定。因此，鸣禽听觉系统和运动系统对刺激的感觉运动整合过程是非常重要的。近年研究发现，感觉期幼鸟编码记忆模板的过程需要NIf-HVC投射的参与，同时这一突触联系与维持成年鸣禽可塑性鸣曲空间特征和鸣曲节律至关重要，其中，NMDAR、AchR和NE可能参与调节NIf-HVC突触的效能。HVC类似于人类的Broca区，而NIf类似于人类的Spt区，因此研究NIf-HVC突触在神经环路中的作用有助于揭示人类这两个脑区在语言形成中潜在的功能，有利于探索发声过程相关的感觉运动信息整合的机制     

鸣禽鸟脑的季节可塑性

呜禽鸟的发声控制脑区具有明显的季节可塑性变化，它是鸣啭季节差异的神经基础．目前鸣禽成鸟的发声控制系统已成为研究中枢神经系统形态和功能可塑性的重要模型．本文着重就引起发声控制核团或脑区体积改变的诱导因素和触发体积改变的机制进行探讨．     

探讨歌唱中的咬字吐字

声乐艺术是音乐艺术范畴中，唯一直接运用语言和音乐相结合表达思想感情，塑造艺术形象的艺术形式。在初学发声时，就应该懂得发声与咬字，吐字与情感表达之间不可分割的特殊关系。只有基于这种观念而建立的歌唱发声方法，才是真正完善而有效的发声方法。     

人类说话的秘密

语言是思维的工具，是人类区别于动物的最大特征之一。除此之外，你对语言究竟了解多少？1、人类的喉结位置比黑猩猩等灵长类动物更低。人类独特的较大发声系统，使人类具备说话和唱歌必备的宽泛音域，只有人类才有真正的语言。     

链霉素对鸟类听觉毛细胞损伤的研究

将健康成年虎皮鹦鹉（Melopsitiacus undelafusp）分成三批按120mg／kg的剂量连续注射链霉素15天，分别于停药后15天、30天、60天时处死，对照组不给任何药物．然后制作石蜡切片并用光镜观察，检测对比实验组与对照组之间的不同．结果表明随着时间增加，高毛细胞数目增加，是毛细胞再生的结果；而矮毛细胞数目减少，直接导致了听力敏感性降低．可见毛细胞的再生是有可能的．     

海人酸致沙鼠癫痫模型初探

采用腹腔注射海人酸(KA)的方法制作沙鼠癫痫模型。结果显示,实验中所设的四个剂量组(5 mg/kg,10mg/kg,15 mg/kg,20 mg/kg)均能成功诱发癫痫发作,是良好的颞叶癫痫动物模型。随着KA剂量的增加,沙鼠癫痫发作的潜伏期、发作时间均明显缩短(P<0.01),但动物的死亡率增加(P<0.01)。提示制作沙鼠癫痫模型时腹腔注射KA的适宜剂量是5 mg/kg。     

5％AVM水悬液对绵羊胃、肠道线虫驱除试验

本试验再次证实阿维菌素的确是一种低毒高效广谱抗体内寄生虫的驱虫药，不同剂量5％AVM水悬液0．5mg/kg b．w．、lmg／kg b．w．、1．5mg／kg b．w．与1％阿维菌素注射液0．2mg/kg b．w．驱虫效果一致，虫卵减少率和粗计驱虫率均达100％。     

秋季黄胸巫鸟发声相关核团体积的雌雄差异

利用组织方法及微机处理技术测量了秋季成年雌、雄鸣禽黄胸巫鸟（ Ｅｍ ｂｅｒｉｚａ ａｕｒｅｏｌａ）发声相关核团 Ｈ Ｖｃ、 Ｒ Ａ、 Ｘ 区、ｎⅩⅡｔｓ 以及与发声无关的核团（ Ｓｐ Ｍ）的体积．结果表明：前脑的发声相关核团 Ｈ Ｖｃ、 Ｒ Ａ 及 Ｘ区具有明显的雌雄差异,而延髓的ｎⅩⅡｔｓ 以及与发声无关的核团 Ｓｐ Ｍ 则差异不明显     

阿霉素对昆明种小白鼠腹腔给药的半致死剂量研究

目的:研究阿霉素对小白鼠经腹腔给药途径的半致死剂量.方法:通过预实验得到近似的最大致死剂量(Dm)和最小致死剂量(Dn),在正式实验中,将70只小鼠随机分为7组,每组10只,雌雄各半.给药途径为腹腔注射,给药次数1次,给药剂量为对照组给生理盐水,其余六组的剂量分别是13.4 mg/kg、19.2 mg/kg、27.4 mg/kg、39.2 mg/kg、56 mg/kg、80 mg/kg.给药后观察时间为14 d,统计小鼠的死亡情况.结果:除对照组和最小剂量(13.4 mg/kg)外,其他剂量组在7 d内均有数量不等的动物死亡,并且死亡率随着阿霉素浓度的增加而递增.经Bliss软件计算,其LD50值为24.941 mg/kg,95%的可信限为21.241～29.271 mg/kg.     

Precise auditory-vocal mirroring in neurons for learned vocal communication

Brain mechanisms for communication must establish a correspondence between sensory and motor codes used to represent the signal. One idea is that this correspondence is established at the level of single neurons that are active when the individual performs a particular gesture or observes a similar gesture performed by another individual. Although neurons that display a precise auditory-vocal correspondence could facilitate vocal communication, they have yet to be identified. Here we report that a certain class of neurons in the swamp sparrow forebrain displays a precise auditory-vocal correspondence. We show that these neurons respond in a temporally precise fashion to auditory presentation of certain note sequences in this songbird's repertoire and to similar note sequences in other birds' songs. These neurons display nearly identical patterns of activity when the bird sings the same sequence, and disrupting auditory feedback does not alter this singing-related activity, indicating it is motor in nature. Furthermore, these neurons innervate striatal structures important for song learning, raising the possibility that singing-related activity in these cells is compared to auditory feedback to guide vocal learning.     

洞庭湖区土壤、稻米的镉问题及其治理

镉是1984年联合国环境规划署提出的具有全球意义的12种危害物质之一。已披露的资料表明,稻田土壤中镉含量大于0.87mg/kg,稻米中镉含量大于1.13mg/kg,长期通过食物链可导致人出现镉中毒病症。洞庭湖区浅层土壤中镉含量均值为0.36mg/kg,深层土壤中均值为0.14mg/kg;稻米中镉含量早稻均值为0.06mg/kg,晚稻均值为0.16mg/kg。洞庭湖区农田按现镉水平及种植的现水稻品种来看,稻米食品是安全的。但是如果稻田土壤镉还在累积,又种植富集镉强势的超级杂交稻,那么难免有一天会出现稻米食品不安全,因此不使现在水稻土壤有镉的累积最为关键。     

Pulmonary toxicity induced by three forms of titanium dioxide nanoparticles via intra-tracheal instillation in rats

Titanium dioxide (TiO2) nanoparticles are in wide commercial use worldwide. To evaluate if acute pulmonary toxicity can be induced by nano-TiO2 particles, rats were intra-tracheally instilled with 0.5, 5, or 50 mg/kg of 5, 21, and 50 nm TiO2 primary particles. Toxic effects were determined with the coefficients of lung tissues to body weight, histopathology, biochemical parameters of blood, activity of lactate dehydrogenase (LDH), alkaline phosphatase (ALP) and acid phosphatase (ACP) in tissues, and the phagocytotic ability of alveolar macrophages (AMs). All the indicators were observed in sacrificed rats one week post-exposure. There was a significant difference of coefficients of pulmonary tissues between the high-dose group and the low- or moderate-dose groups with an exposure of 5 nm TiO2. At the same time, 5 nm TiO2 primary particles increased the activity of LDH and ALP when exposure dose was >5 mg/kg. A significant difference in LDH and ALP activity was observed between the 50 mg/kg group and 0.5 or 5 mg/kg group with exposure of 5 nm TiO2. Lung tissues showed increased ALP activity only if treated with 5 and 50 mg/kg of 21 nm TiO2 particles. There was no significant difference in LDH and ALP activity in the 50 nm TiO2 group and control group. Histopathologic examination of lung tissues indicated that the pulmonary response to exposure to TiO2 particles in rats manifested as dosedependent inflammatory lesions, which mainly consisted of infiltration of inflammatory cells and interstitial thickening. Analysis of uptake of neutral red dye showed that 50 nm TiO2 particles significantly increased phagocytotic ability of AMs compared with controls (P < 0.05), whereas exposure with 5 nm TiO2 reduced the phagocytotic ability of AMs when the exposure dose was 50 mg/kg. These results suggest that particle size and exposure dose may have important roles in pulmonary toxicity. The toxic effect of TiO2 nanoparticles in lung tissue exhibited a dose–response relationship. After exposure with TiO2 particles of >5.0 mg/kg, 5 and 21 nm TiO2 particles induced standing pulmonary lesions; and 5 nm TiO2 particles may suppress the phagocytotic ability of AMs if exposure dose was ≥50 mg/kg. Pulmonary toxicity caused by 5 nm TiO2 particles was more severe than that caused by 21 and 50 nm TiO2 particles.     

甲基杀虫脒盐酸盐在小鼠体内致突变研究

甲基杀虫脒盐酸盐作为一种化学诱变物具有一定致突变性。本研究设计中突变的最低剂量组1/50LD50=4.48mg/kg体重,在小鼠骨髓细胞微核出现率中,与对照组比较,呈极显著性差异。因此,无作用剂量组应低于4.5mg/kg体重。染色体畸变的最低剂量在1/5LD50与阴性对照组有极显著性差异,染色体畸变的无作用剂量在8.95～44.76mg/kg范围内。     

Bird song: superfast muscles control dove's trill

Bird songs frequently contain trilling sounds that demand extremely fast vocalization control. Here we show that doves control their syrinx, a vocal organ that is unique to birds, by using superfast muscles. These muscles, which are similar to those that operate highly specialist acoustic organs such as the rattle of the rattlesnake, are among the fastest vertebrate muscles known and could be much more widespread than previously thought if they are the principal muscle type used to control bird songs.     

桦木酮酸抑制PI3K/AKT通路体内抗肿瘤作用研究

采用免疫细胞化学法对H22细胞中的PI3K、AKT蛋白进行检测;分光光度法检测H22细胞中Caspase-3,9的活性对桦木酮酸通过抑制PI3K/AKT通路抗H22肝癌腹水瘤的机制进行初步研究.结果表明,桦木酮酸给药量为500 mg/（kg·d）和1000 mg/（kg·d）时,对H22腹水瘤有显著的抑制作用;当桦木酮酸给药量为1000 mg/（kg·d）时,PI3K和AKT蛋白的表达分别从56%和60%降到28%和31%;Caspase-3,9的活性在桦木酮酸给药量为500 mg/（kg·d）和1000 mg/（kg·d）时,与空白组相比均有显著性差异.说明桦木酮酸可能通过抑制PI3K/AKT细胞存活通路抑制细胞增殖,并通过提高Caspase-3,9的活性促进细胞凋亡而起到抗肿瘤的作用.     

去势对成年雄性斑胸草雀HVC神经元电生理特性的影响

鸣唱控制系统的高级发声中枢HVC（high vocal center）是发声运动通路和前端脑通路的始端，是发声行为的起始控制脑区，亦可接受听觉信号的输入及反馈，是鸣禽鸣唱调控最为重要的脑区.以往研究表明,雄激素及其代谢产物对鸣禽鸣唱控制有重要作用.去势显著改变鸣禽体内激素含量，进而影响鸣禽鸣曲稳定性，但其具体机制尚未阐明.我们运用全细胞膜片钳记录法，在离体细胞水平研究了去势引起的雄激素水平降低对HVC不同神经元电生理特性的影响.研究结果显示,去势组与对照组相比，投射神经元HVCRA，HVCX膜输入电阻减小，膜时间常数降低，动作电位后超极化幅值升高及达到峰值时间延长，表明雄激素可以提高两类投射神经元的兴奋性. 综上所述，雄激素可以一定程度上提高HVC神经元的兴奋性，雄激素可增强HVC对发声运动通路（vocal motor pathway,VMP)的控制，抑制前端脑通路(anterior forebrain pathway,AFP)来实现维持鸣曲的稳定.     

静脉胺碘酮在恶性室性心律失常中的应用

目的静脉应用胺碘酮对危及生命的室性心律失常的临床应用经验。方法42例合井器质性心脏病的反复发作持续性室性心动过速（VT）/心室颤动（VF）患者,静脉注射胺碘酮首剂3～5mg/kg,10min注入,继之以1．0～1．5rag/min维持静脉点滴,以后依病情渐减。静脉应用同时加用口服600-1200mg/24h。第1次负荷量后,若心律失常控制不理想,可每隔15～30min再给1．5～3．0mg/kg的追加负荷量,以VT、VF消失为有效。结果总有效率85．7％。对持续性VT终止率25％。静脉用药早期对PR、QTc间期、QRS波时限无影响。静脉用药期间,2例出现窦性心动过缓,经减量后恢复;1例出现一过性Ⅱ度房室阻滞;8例出现静脉炎。结论静脉胺碘酮治疗危及生命的室性心律失常安全有效。24h 1000～1500mg为较合适的初始静脉用量。     

Neural substrates of vocalization feedback monitoring in primate auditory cortex

Vocal communication involves both speaking and hearing, often taking place concurrently. Vocal production, including human speech and animal vocalization, poses a number of unique challenges for the auditory system. It is important for the auditory system to monitor external sounds continuously from the acoustic environment during speaking despite the potential for sensory masking by self-generated sounds. It is also essential for the auditory system to monitor feedback of one's own voice. This self-monitoring may play a part in distinguishing between self-generated or externally generatedauditory inputs and in detecting errors in our vocal production. Previous work in humans and other animals has demonstrated that the auditory cortex is largely suppressed during speaking or vocalizing. Despite the importance of self-monitoring, the underlying neural mechanisms in the mammalian brain, in particular the role of vocalization-induced suppression, remain virtually unknown. Here we show that neurons in the auditory cortex of marmoset monkeys (Callithrix jacchus) are sensitive to auditory feedback during vocal production, and that changes in the feedback alter the coding properties of these neurons. Furthermore, we found that the previously described cortical suppression during vocalization actually increased the sensitivity of these neurons to vocal feedback. This heightened sensitivity to vocal feedback suggests that these neurons may have an important role in auditory self-monitoring.     

原儿茶酸在大鼠血浆中的药代动力学研究

研究原儿茶酸在大鼠血浆中的药代动力学.以原儿茶酸50、100、150 mg/kg(低、中、高)3剂量对大鼠灌胃给药,血浆样品经甲醇乙腈沉淀蛋白后,用HPLC法测定原儿茶酸的浓度,绘制药时曲线.实验数据用3P97药动学软件处理,得相应药动学参数.原儿茶酸在大鼠体内的药动学过程符合二室开放模型.原儿茶酸在剂量由50 mg/kg增至100 mg/kg时药动学过程呈现出非剂量依赖,具有非线性特征;其剂量由100 mg/kg增至150 mg/kg时药动学过程呈现出剂量依赖,具有线性特征.对于其产生非线性特征的原因,需要通过进一步实验进行研究确证.