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Changes of summating potentials and morphology in theguinea pig cochlea during anoxia

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Chinese Journal of Acoustics 1995年第4期14卷 358-363页

作者： li xingqi SUN Jianhe SUN Wei and JIANG Sichang(Institute of Oiorhinolaryngology PLA, General Hospital, Beijing 100853)

The dynamic changes in CAP, and EP in the scale media were examined with single micropipet during anoxia and reventilation with oxygen. Also, the morphologic changes in IHC, OHC and synapse were observed in this experiment. It was found that the amplitude of SP and EP values declined with alteration in polarity of these value. The changes in polarity and amplitude of SP followed the changes of CAP threshold induced by anoxia. The histologic examinations revcaled no cvidence of acetylcholinesterase (AChE) alteration in the synapse and no succinict dehydrogenase (SDH) changes in IHC appeared. However, the activity of SDH in the OHC decreased. The results suggest that the polarity and amplitude of SP were influenced passively by the changes of EP value. In addition, the change of SP polarity from positive tonegative during anoxia is due to the loss of mudulation process of OHC to IHC, while the SP polarity from negative to positive during the supply of oxygen is caused by regain of the modulation process of OHC.

关键词： Audiometry Evoked response Anoxia

Amplitude recruitment of cochlear potential

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Chinese Journal of Acoustics 2001年第1期20卷 11-17页

作者： li xingqi,SUN Wei,SUN Jianhe,YU Ning,JIANG Sichang (The Institute of Otolaryngology, PLA General Hospital Beijing 100853) The Institute of Otolaryngology PLA General Hospital Beijing100853

Intracellular recordings were made from outer hair cells (OHC) and the cochlear microphonics (CM) were recorded from scala media (SM) in three turn of guinea pig cochlea, the compound action potential (CAP) were recorded at the round window (RW) before and after the animal were exposed to white noise. The results suggest that the nonlinear properties with 'saduration' of input/output (I/O) function of OHC AC recepter potential and CM were founded; the nonlinear properties with 'Low', 'Plateau' and 'high' of CAP also were investigated. After explosion, the threshold shift of CAP has about 10 dB. The I/O of OHC responses and CM were changed in a linearizing (i.e., nonlinearity loss), the 'plateau' of I/O CAP disappeared and the growth rate of CAP amplitude were larger than before explosion. The response amplitude recruitment of OHC appears to result from reduction in gain (i.e., hearing loss); It was due to the nonlinear growth function of OHC receptor potentials was changed in linearzing that the basilar membrance motion was changed in linearizing. Since intensity coding in the inner ear depends on an interactions of nonlinear basilar membrance and nerve fibers. So that it must lead to a linearizing of CAP as input responses.

关键词： cell Amplitude recruitment of cochlear potential

Abnormal augmentation of the receptor potential and morphology changes of guinea pig's cochlea induced by Cisplatin

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Chinese Journal of Acoustics 2000年第1期19卷 1-9页

作者： li xingqi SUN Wei SUN Jianhe YU Ning JIANG Sichang (Institute of Otolaryngology, General Hospital of PLA Beijing 100853) Institute of Otolaryngology General Hospital of PLA Beijing100853

To investigate the characteristics of cochlear microphonic (CM), summating potential (SP) and compound action potential (CAP) and morphology changes of outer hair cells (OHCs) and inner hair cells (IHCs) after OHCs were selectively damaged by acute cochlear perfusion of cisplatin. Dynamic changes of CM, SP and CAP were recorded from the scala media of the third turn of the guinea pig's cochlea during Cisplatin perfusion into the whole cochlea for 2 hours. The results indicated that after one hour of the perfusion, the amplitude of CM, SP and CAP decreased at stimulus intensity litude increased at stimulus intensity > 70 dB SPL, as compared to those examined before perfusion of Cisplatin (the average of CM increased by 3.6 mV at 90 dB SPL, average of SP increased by 1.6 mV at 120 dB SPL, average of CAP increased by 0.23 mV at 90dB SPL). After two hours of perfusion, the amplitude of CM, SP and CAP decreased in all stimulus intensities. The staining of Succinic Dehydrogenase (SDH) was weak in OHCs, while the stain ing of IHCs remained normal. transmission electron microscopic examination of organ of Corti showed varieties of morphological changes in OHCs, such as nucleus chromosome disappear, mitochondria denaturalization and number reduction, while the structure of IHC appeared normal. SDH staining showed normal staining pattern in both IHCs and OHCs when the cochlea was perfused with artificial perilymph for 2 hours. The abnormal augmentation phenomenon of CM and SP may be induced by the abnormal control of Ca++ in IHCs and OHCs. The abnormal augmentation of CAP suggests that the suppression effects of OHCs and efferent neurotransmitter on IHCs and afferent neurotransmitter may be reduced after OHCs damaged.

关键词： Cisplatin guinea augmentation perfusion cisplatin auditory cochlear evoked stria appeared

Changes of summating potentials in the guinea pig cochlea after impulse sound exposure

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Chinese Journal of Acoustics 2003年第4期22卷 297-301页

作者： li xingqi LU Yunyun SUN Wei SUN Jianhe(Institute of Otorhinolaryngology, Chinese PLA General Hospital Beijing 100853)

Compound action potentials (CAP) and action potential-summating potential com-plex (AP-SP) evoked by click and tone burst respectively were recorded from the round window in guinea pigs. Correlations between the positive and negative summating potentials (SP+ and SP-) were examined befroe and after impulse sound exposure. The results show that the SP-is related to CAP threshold shift. In comparison to normai condition, it appears with high incidence when auditory threshold shift reaches 30 dB or more. SP- increases in amplitude when SP+ decreases. The smaller the amplitude of SP+, the larger that of SP-. This suggests that in normai hearing condition SP- may be suppressed by SP+. Such suppression may be released if OHC are injured. The dominant SP- as a sign of recruitment may be due to the change in the nonlinear character of IHC following OHC damage.

关键词： of is on et in SP Changes of summating potentials in the guinea pig cochlea after impulse sound exposure OHC

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综合评价方法中的最优无量纲化模型研究

统计与决策 2024年第5期40卷 44-49页

作者：李兴奇高晓红楚雄师范学院管理与经济学院云南楚雄675000 楚雄师范学院数学与计算机科学学院云南楚雄675000

针对综合评价过程中无量纲化方法选择盲目性较强的问题,文章首先引入综合评价结果优良性的度量指标,优化综合评价结果稳定性和区分度的度量函数,建立无量纲化有效性的统计检验方法;其次,以无量纲化有效为主要约束条件,分别以稳定性最高... 详细信息

针对综合评价过程中无量纲化方法选择盲目性较强的问题,文章首先引入综合评价结果优良性的度量指标,优化综合评价结果稳定性和区分度的度量函数,建立无量纲化有效性的统计检验方法;其次,以无量纲化有效为主要约束条件,分别以稳定性最高、区分度最高以及稳定性和区分度均最高为目标函数构建三类最优无量纲化模型,分析大平移尺度和小平移尺度约束条件对最优无量纲化模型的影响;最后,通过大量的数值模拟实验研究了6种常用综合评价方法中的最优无量纲化模型,并对结果进行深入分析。研究发现,大平移尺度约束下几种综合评价方法中的最优无量纲化结果均不同于现有无量纲化方法,小平移尺度约束下的最优无量纲化与均值化较为接近,但不完全相同;经过不断优化后的稳定性函数和区分度函数能更科学地度量综合评价结果的稳定性和区分度大小,无量纲化有效性的统计检验方法能准确判断指标间的量纲差异是否被有效消除;综合评价方法、目标函数和约束条件不同时所对应的最优无量纲化结果不同。

关键词：综合评价方法最优无量纲化模型稳定性区分度有效性

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综合评价结果的区分度与稳定性研究

统计与决策 2022年第16期38卷 16-21页

作者：李兴奇高晓红楚雄师范学院管理与经济学院云南楚雄675000 楚雄师范学院数学与计算机科学学院云南楚雄675000

综合评价是一项系统而又复杂的工作,其目的是获取能反映被评价对象全貌的综合评价值来区分不同个体的优劣。好的综合评价结果应该具备较高的区分度和稳定性,因此如何科学度量评价值的区分度和稳定性成为综合评价结果可靠与否的关键。文... 详细信息

综合评价是一项系统而又复杂的工作,其目的是获取能反映被评价对象全貌的综合评价值来区分不同个体的优劣。好的综合评价结果应该具备较高的区分度和稳定性,因此如何科学度量评价值的区分度和稳定性成为综合评价结果可靠与否的关键。文章构建一种新的区分度度量方法,提升了区分度的准确性和适用性;分析了导致综合评价结果波动的诸多因素,引进综合评价结果稳定性的度量指标,并证明了该指标的科学性与合理性;通过大量的数值模拟实验来计算不同综合评价方法的区分度和稳定性,研究区分度和稳定性的影响因素。结果表明,不同分布类型数据的取值规律不同,不同无量纲化方法处理数据的效用不同,不同综合评价方法确定权重的机理不同,任何一种因素的改变都会对综合评价结果的区分度和稳定性产生影响,所以进行综合评价前需要充分考虑数据的分布类型进而选择恰当的无量纲化方法和综合评价方法,以提高结果的区分度和稳定性。

关键词：综合评价区分度稳定性无量纲化数值模拟

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服从不同分布数据的无量纲化方法研究

统计与决策 2022年第10期38卷 31-36页

作者：李兴奇高晓红楚雄师范学院管理与经济学院云南楚雄675000 楚雄师范学院数学与计算机科学学院云南楚雄675000

无量纲化的优点是能缩小指标间的量纲差异,缺点是容易造成原始信息损失,科学评价无量纲化方法的利弊有助于寻找不同分布中的最佳无量纲化方法,提高数据的处理质量。文章分别构建无量纲化效果和信息损失情况的评价指标,通过数值模拟实验... 详细信息

无量纲化的优点是能缩小指标间的量纲差异,缺点是容易造成原始信息损失,科学评价无量纲化方法的利弊有助于寻找不同分布中的最佳无量纲化方法,提高数据的处理质量。文章分别构建无量纲化效果和信息损失情况的评价指标,通过数值模拟实验来比较不同分布中各无量纲化方法的效果和信息损失速率。结果发现,无量纲化过程中利弊并存,不同分布数据适用的无量纲化方法不同,需要综合考虑数据的分布特点和研究的需要来选择无量纲化方法,其中线性无量纲化不改变数据的分布特征,伸缩法不改变数据的变异性,平移法不改变数据的差异性大小,归一化和规范化的无量纲化效果较好,但信息损失速率较快。

关键词：不同分布无量纲化方法无量纲化的效果信息损失速率弹性

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排水对我国两种典型湿地土壤有机碳微生物转化过程的影响

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应用生态学报 2024年第1期35卷 133-140页

作者：贾娟李星奇冯晓娟中国科学院植物研究所植被与环境变化国家重点实验室北京100093 国家植物园北京100093 中国科学院大学北京100049

湿地储存了全球三分之一的土壤有机碳(SOC),并受到人为排水的强烈影响。然而,排水引起的水位下降对不同湿地碳循环(特别是微生物转化)过程的影响尚不明确。为此,本研究以我国两种典型湿地(贫营养型的大九湖湿地和富营养型的红原湿地)土... 详细信息

湿地储存了全球三分之一的土壤有机碳(SOC),并受到人为排水的强烈影响。然而,排水引起的水位下降对不同湿地碳循环(特别是微生物转化)过程的影响尚不明确。为此,本研究以我国两种典型湿地(贫营养型的大九湖湿地和富营养型的红原湿地)土壤为研究对象,通过添加13C标记葡萄糖的室内培养试验,分析了短期和长期排水对SOC降解、胞外酶活性、微生物碳利用效率(CUE)和微生物碳积累效率(CAE)的影响。结果表明:长期和短期排水显著提高了两种湿地SOC降解速率(从淹水处理的1.47μg C·g^(-1)·h^(-1)升高到排水处理的2.47μg C·g^(-1)·h^(-1))、葡萄糖来源的微生物生物量碳(从0.21 mg C·g^(-1)升高到1.00 mg C·g^(-1))和CAE(从0.29升高到0.73),但未改变CUE(变化范围为0.34~0.86)。长期排水提高了大九湖湿地α-葡萄糖苷酶活性,但降低了红原湿地β-葡萄糖苷酶和酚氧化酶活性。综上,排水主要通过增强微生物胞内代谢过程(包括呼吸)提高湿地土壤“微生物碳泵”作用和效率,同时加速了SOC降解。

关键词：微生物碳利用效率微生物碳积累效率土壤有机碳循环湿地排水

铜催化炔基溴与丙炔醇的偶联-异构化反应合成戊炔烯酮

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有机化学 2015年第3期35卷 610-617页

作者：杨宗莲廖沛球李兴奇毕锡和东北师范大学化学学院长春130024 南开大学元素有机化学国家重点实验室天津300071

乙炔溴和丙炔醇在哌啶溶剂中,用醋酸铜作催化剂,能够发生偶联-异构化反应获得具有立体选择性的唯一产物（E）-1,5-二取代-戊-2-烯-4-炔-1-酮.机理研究表明,哌啶在反应体系中起到了溶剂和碱的双重作用.该反应具有简单、高效、反应范围宽... 详细信息

乙炔溴和丙炔醇在哌啶溶剂中,用醋酸铜作催化剂,能够发生偶联-异构化反应获得具有立体选择性的唯一产物（E）-1,5-二取代-戊-2-烯-4-炔-1-酮.机理研究表明,哌啶在反应体系中起到了溶剂和碱的双重作用.该反应具有简单、高效、反应范围宽泛等特点,能够以40%~83%的产率获得目标产物反式1,5-二取代的戊炔烯酮.

关键词：戊炔烯酮乙炔溴丙炔醇偶联-异构化反应