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Effects and its possible mechanism of Radix Saposhnikoviae on rat colonic smooth muscle in vitro

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Journal of Nanjing Medical University 2009年第5期23卷 311-316页

作者： zhenqing liu Tao Lü Ping Hu Muxin Wei Department of Traditional Chinese Medicine the First Affiliated Hospital of Nanjing Medical University Nanjing 210029 China

Objective： To determine the effect of different concentrations of Radix Saposhnikoviae （RS） on the contraction of smooth muscle strips and the Ca2＋ mobilization of cultured smooth muscle ceils of rat colon and its possible mechanism of action. Methods： Strips of rat colon longitudinal muscle were prepared and smooth muscle cells from rat colon were isolated and cultured. In the experiments, in vitro muscle strips were suspended in an organ bath and the contraction of the strips was recorded. In the cell- experiments, intracellular Ca2＋ was assessed using fluorescent intensity （FI） of smooth muscle cells loaded with Fluo-4/AM, measured with a laser scanning confocal microscope and related software. Results： In the in vitro experiment, RS （0.02, 0.2, 2, 20 g/L） inhibited contraction of muscle strips in a concentration-dependent manner, and this inhibition was significant for the three higher RS concentrations （P 〈 0.01） for both Peak （the maximal contraction amplitude） and Area （the area under curves）. Similarly, RS inhibited Ach-induced contraction. In these experiments the inhibition of the Peak values in the RS 2 and 20 g/L groups was significant （P 〈 0.01）, as was the inhibition of the Area values in all RS groups （P 〈 0.05）. Naloxone and propranolol did not significantly affect the inhibitory effect of RS on smooth muscle contractility, while phentolamine significantly reduced the inhibitory effect （P 〈 0.01）. In experiments using primary smooth muscle cell cultures in Ca2＋ - containing buffer, the post-treatment fluorescence of cells in the RS 0.2, 2 and 20 g/L groups differed significantly from pre-treatment values （P 〈 0.05）, and the percent inhibition of fluorescence in the RS 2 g/L and 20 g/L groups was significant （P 〈 0.01）. However, in Ca2＋-free buffer, FS had no significant effect on cell fluorescence. Conclusion： RS inhibited both the spontaneous and Ach-stimulated contraction of rat colonic smooth muscle strips. This RS effect appeared to involve α -ad

关键词： Radix Saposhnikoviae Colonic smooth muscle strips contraction Colonic smooth muscle cells lntracellular Ca^2+

Control of the Rendition Wavelength Shifts of Color Lippmann Holograms Recordedin Single-layer panchromatic Silver-halide Emulsion

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Chinese Journal of Lasers 2000年第2期9卷 155-160页

作者： ZHU Jianhua, GUO Lurong, LI Zuoyou, liu zhenqing (Information Optics Institute, Sichuan University, Chengdu 610064, China Institute of Southwest Find Physics, Chengdu 610003, China ) 四川大学四川成都中国工程物理研究院西南流体物理所四川成都

Russian PFG-03C panchromatic ultra-high resolution silver-halide emulsion is regarded as the most successful material for the fabrication of color reflection holograms. But the lack of established and reliable processing sequences prevents its practical applications in business and everyday life. Though much attention is drawn upon the processing of PFC-03C color reflection holograms, the color desaturation is still a problem. The article describes the new processing of color holograms recorded in PFC- 03C plates which is demonstrated experimentally to have the capacity of controlling the rendition wavelength shifts and improving the color desaturation effectively. The rendition spectra of Red-Green-Blue (R. G. B. ) single-line reflection holographic gratify, and the color reflection hologram as well, are given in this paper.

关键词： color holography reflection holograms rendition wavelength color desaturation

A phase deviation based split-spectrum processing algorithm for ultrasonic flaw detection

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Chinese Journal of Acoustics 2002年第1期21卷 36-44页

作者： liu zhenqing (Institute of Acoustics, Tongji University Shanghai 200092) Institute of Acoustics Tongji University Shanghai200092

The Split Spectrum Processing (SSP) technique has proved its ability in reduction of interference noise in ultrasonic nondestructive testing for coarse gained materials. However, the results of SSP algorithms are not sufficiently stable since they are sensitive to the filter bank and filter parameters. And the mechanism of the technique to fully explore the signals is not clear. The statistical phase response characteristic of filter outputs for ultrasonic testing is discussed. Thus, a new SSP algorithm based on phase standard deviation is proposed. The performance is examined for both computer simulated and experimental data, and compared to commonly used minimum algorithm. The phase standard deviation algorithm is proved its superior effect and is less sensitive on the number of filters.

关键词： SSP

Propagation of Iamb waves in adhesively bonded multilayered media

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声学技术 2003年第Z1期22卷 40-43页

作者： ZHANG Haiyan XIE Yuanxia liu zhenqing School of Communication and Information Engineering Shanghai UniversityShanghai 200072China Institute of Acoustics Tongji UniversityShanghai 200092China

The effect of introducing attenuation on Lamb wave dispersion curves is studied in this paper. Attenuation is introduced to a three-layered composite plate by an adhesive bond layer with viscous behavior. No changes are required to the transfer matrix formulation for the propagation of elastic waves. By introduction of a complex wavenumber, the model can be used to the propagation of attenuative Lamb waves. Numerical examples for a three-layered aluminium-epoxy-aluminium plate show that attenuation values of each mode in plates are related not only to attenuation, but also to the thickness of the bonded layer, which is in agreement with practical situations.

关键词： adhesive bond multilayered media Lamb waves attenuation dispersion

Ultrasonic study of nitric acid

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Chinese Journal of Acoustics 1995年第4期14卷 364-372页

作者： liu zhenqing(Institute of Acoustics, Tongji University, Shanghai 200092)

Ultrasonic velocity was measured by an automatic pulse-echo velocimeter at various temperatures in nitric acid at various concentrations ranging from 20 to 99%. The various parameters i.e. molar sound velocity, specific acoustic impcdance, adiabatic compressibility,intermolecular free length for the solution and the ultrasonic velocity of pure nitric acid were computed from the measurement results. Excess ultrasonic velocity, excess molar volume, excess adiabatic compressibility and excess intermolecular free length, were also calculated. The results show that with increasing concentration of nitric acid the strength of ion-ion interaction in the solution may first increase to a maximum and then decreases.

关键词： Nitric acid Ultrasonic velocity Automatic pulse-echo velocimeter

Fuzzy detection for ultrasonic flaw inspectionof highly scattering materials

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Chinese Journal of Acoustics 1997年第4期16卷 332-338页

作者： liu zhenqing and WEI Moan (Institute of Acocustics, Tongji University Shanghai 200092)

Fuzzy logic detection has been applied to the signal enhancement of ultrasonic flaw echoes from the structure noise due to nonflaw related scattering of ultrasound in highly scattering materials. Cross-correlation, phase difference and fractal dimension are used as signal characteristics in fuzzy logic detection. Experimental results show that this new method has better performance than the commonly used correlation detection.

关键词： Fuzzy detection for ultrasonic flaw inspectionof highly scattering materials Wang

Experimental analysis of acousto-ultrasonic wave propagation mode in thin plate

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Chinese Journal of Acoustics 2000年第3期19卷 277-284页

作者： liu zhenqing HUANG Ruiju (Institute of Acoustics, Tongji University Shanghai 200092)

in the acousto-ultrasonic technique, a broadband ultrasonic wave is injected onto the surface at one location of the tested plate with the help of a longitudinal transducer and a receiving transducer is coupled to the same surface at another location. Thus, understanding the propagation characteristics of the ultrasonic wave is essential for successful application of the technique. It has been found that the dominant acousto-ultrasonic waves produced experimentally in thin plate are multi-mode Lamb waves. The broadband generation and detection of Lamb waves have been performed in two aluminum plates with different thickness using the acousto-ultrasonic method.

关键词： wave mode Experimental analysis of acousto-ultrasonic wave propagation mode in thin plate

The ERα/KDM6B regulatory axis modulates osteogenic differentiation in human mesenchymal stem cells

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Bone Research 2022年第1期10卷 95-106页

作者： zhenqing liu Hye-Lim Lee Jin Sook Suh Peng Deng Chang-Ryul Lee Olga Bezouglaia Mojan Mirnia Vivian Chen Michael Zhou Zhong-Kai Cui Reuben HKim Min Lee Tara Aghaloo Christine Hong Cun-Yu Wang Division of Oral Biology and Medicine School of DentistryUniversity of CaliforniaLos Angeles(UCLA)Los AngelesCA 90095USA Department of Anatomy&Neurobiology University of CaliforniaIrvine(UCI)IrvineCA 92697USA Department of Orofacial Sciences School of DentistryUniversity of CaliforniaSan Francisco(UCSF)San FranciscoCA 94143USA School of Dentistry University of CaliforniaSan Francisco(UCSF)San FranciscoCA 94143USA Division of Diagnostic and Surgical Sciences School of DentistryUniversity of CaliforniaLos Angeles(UCLA)Los AngelesCA 90095USA School of Dentistry University of CaliforniaLos Angeles(UCLA)Los AngelesCA 90095USA Division of Advanced Prosthodontics School of DentistryUniversity of CaliforniaLos Angeles(UCLA)Los AngelesCA 90095USA Division of Constitutive and Regenerative Sciences School of DentistryUniversity of CaliforniaLos Angeles(UCLA)Los AngelesCA 90095USA Department of Bioengineering University of CaliforniaLos Angeles(UCLA)Los AngelesCA 90095USA

Osteoporosis is a highly prevalent public health burden associated with an increased risk of bone fracture, particularly in aging women. Estrogen, an important medicinal component for the preventative and therapeutic treatment of postmenopausal osteoporosis, induces osteogenesis by activating the estrogen receptor signaling pathway and upregulating the expression of osteogenic genes, such as bone morphogenetic proteins(BMPs). The epigenetic regulation of estrogen-mediated osteogenesis,however, is still unclear. In this report, we found that estrogen significantly induced the expression of lysine-specific demethylase 6B(KDM6B) and that KDM6B depletion by shRNAs led to a significant reduction in the osteogenic potential of ***, upon estrogen stimulation, estrogen receptor-α(ERα) was recruited to the KDM6B promoter, directly enhancing KDM6B expression. Subsequently, KDM6B was recruited to the BMP2 and HOXC6 promoters, resulting in the removal of H3K27me3 marks and activating the transcription of BMP2 and HOXC6, the master genes of osteogenic differentiation. Furthermore, we found that estrogen enhanced DMSC osteogenesis during calvarial bone regeneration and that estrogen’s pro-osteogenic effect was dependent on KDM6B in vivo. Taken together, our results demonstrate the vital role of the ERα/KDM6B regulatory axis in the epigenetic regulation of the estrogen-dependent osteogenic response.

关键词： expression stimulation ERα

要素短缺、财政支农与农业经济波动效应--基于城乡融合DSGE模型

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中国管理科学 2024年第8期32卷 74-83页

作者：刘振清耿申河南大学中原发展研究院河南郑州450046 陕西省人民政府办公厅陕西西安710006 西安财经大学统计学院陕西西安710100

生产要素离农加剧经济系统性风险,农业支持政策能够促进城乡融合发展。文章基于城乡要素禀赋差异与融合流通机制,构建城乡融合DSGE模型,分析要素短缺和农业支持政策对农业与经济总体的冲击效应。研究发现:(1)劳动供给减少会抑制就业和消... 详细信息

生产要素离农加剧经济系统性风险,农业支持政策能够促进城乡融合发展。文章基于城乡要素禀赋差异与融合流通机制,构建城乡融合DSGE模型,分析要素短缺和农业支持政策对农业与经济总体的冲击效应。研究发现:(1)劳动供给减少会抑制就业和消费,提升生产成本和通胀水平,投资刺激不显著,农业部门与经济总体波动趋势一致,前者波动幅度更大、时间更长。(2)耕地供给减少会加速劳动力非农化,提升农业生产成本,短期内抑制农业发展,总就业和产出增加,工资降低,农业投资增加,通胀加剧,挤出居民消费,经济总体波动一致,但幅度更大。(3)农业生产性补贴会改进要素配置结构,提升配置效率,促进经济增长,农业生产性财政支出会正向影响经济基本面,对农业和经济总体的冲击效应一致;农业技术创新补贴会加速劳动力离农,激发劳动活力,对农业和经济总体产生积极影响,后者波动幅度较大和持续时间较长。因此,要素禀赋短缺将提高生产成本,加剧经济系统性波动;农业支持政策能够提升要素配置效率,促进农业发展,对经济系统产生积极溢出效应。

关键词：要素短缺生产性补贴 DSGE模型模型评价