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On the subspace selection and frequency identification of rotor blade vibration signal measured by blade tip timing
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作者 Zengkun WANG Zhibo YANG +3 位作者 Baijie QIAO min ye Hao ZUO Baoqing DING 《Chinese Journal of Aeronautics》 2025年第7期273-284,共12页
Anti-aliasing spectrum analysis is essential for rotor blade condition monitoring based on Blade Tip Timing(BTT).The Multiple Signal Classification(MUSIC)algorithm,which exploits the orthogonality between signal and n... Anti-aliasing spectrum analysis is essential for rotor blade condition monitoring based on Blade Tip Timing(BTT).The Multiple Signal Classification(MUSIC)algorithm,which exploits the orthogonality between signal and noise subspaces,has been successfully applied for this purpose.However,conventional subspace selection methods relying on fixed thresholds are sensitive to variations in large eigenvalues.Furthermore,the complex disturbances during rotor operation and measurement complicate the identification of blade vibration characteristics.To overcome these challenges,this paper proposes Adaptive Subspace Separation(ASS)and Local Spectral Centroid(LSC)methods to improve the adaptability of subspace selection and the stability of frequency identification,respectively.The impacts of overestimating and underestimating the subspace dimensions on MUSIC's performance are derived mathematically.Simulation and experiments demonstrate the effectiveness of proposed approaches:ASS offers more accurate and stable subspace dimension selection and tracking,while LSC reduces the standard deviation of estimated frequencies by 30 percent. 展开更多
关键词 Blade tip timing Rotor blade Signal subspace Spectrum analysis MUSIC
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Simultaneous determination of 35 constituents and elucidation of effective constituents in a multi-herb Chinese medicine formula Xiaoer-Feire-Kechuan 被引量:5
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作者 Zhanpeng Shang Lulu Xu +6 位作者 Yi Kuang Yan Lin Shuang Liu Long Sun Tao Bo min ye Xue Qiao 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2021年第6期717-725,共9页
Xiaoer-Feire-Kechuan(XFK) is an 11-herb Chinese medicine formula to treat cough and pulmonary inflammation.The complicated composition rendered its chemical analysis and effective-component elucidation.In this study,w... Xiaoer-Feire-Kechuan(XFK) is an 11-herb Chinese medicine formula to treat cough and pulmonary inflammation.The complicated composition rendered its chemical analysis and effective-component elucidation.In this study,we combined quantitative analysis and bioactivity test to reveal the antiinflammatory constituents of XFK.First,UPLC-DAD and UHPLC/Q-Orbitrap-MS methods were established and validated to quantify 35 analytes(covering 9 out of 11 herbs) in different XFK formulations.Parallel reaction monitoring mode built in Q-Orbitrap-MS was used to improve the sensitivity and selectivity.Then,anti-inflammatory activities of the 35 analytes were analyzed using in vitro COX-2 inhibition assay.Finally,major analytes forsythosides H,I,A(8-10),and baicalin(15)(total contents varied from 21.79 to 91.20 mg/dose in different formulations) with significant activities(inhibitory rate ≥ 80%) were proposed as the anti-inflammatory constituents of XFK.The present study provided an effective strategy to discover effective constituents of multi-herb formulas. 展开更多
关键词 Multi-herb formulas Effective constituents Xiaoer-Feire-Kechuan formula(XFK) Parallel reaction monitoring(PRM) Cyclooxygenase-2(COX-2)
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Intestinal Absorption of Ergostane and Lanostane Triterpenoids from Antrodia cinnamomea Using Caco-2 Cell Monolayer Model 被引量:2
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作者 Qi Wang Xue Qiao +5 位作者 Yi Qian Zi-wei Li yew-min Tzeng De-min Zhou De-an Guo min ye 《Natural Products and Bioprospecting》 CAS 2015年第5期237-246,共10页
Antrodia cinnamomea is a precious medicinal mushroom.It exhibits promising therapeutic effects on cancer,intoxication,hypertension,hepatitis,and inflammation.Its major bioactive constituents are ergostane and lanostan... Antrodia cinnamomea is a precious medicinal mushroom.It exhibits promising therapeutic effects on cancer,intoxication,hypertension,hepatitis,and inflammation.Its major bioactive constituents are ergostane and lanostane triterpenoids.In this study,we used intestinal Caco-2 cell monolayer model to reveal the intestinal absorption property of 14 representative triterpenoids from A.cinnamomea.The bidirectional transport through the monolayer at different time points was monitored by a fully validated LC/MS/MS method.In the case of pure compounds,ergostanes 5(25R-antcin H),6(25Santcin H)and 10(25R-antcin B)could readily pass through the Caco-2 cell layer,whereas lanostanes 13(dehydroeburicoic acid)and 14(eburicoic acid)could hardly pass through.When the cells were treated with A.cinnamomea extract,antcins A,B,C,H and K(1–6 and 9–11)were absorbed via passive transcellular diffusion,and showed high PAB and PBA values(>2.5×10^(-5) cm/s).Meanwhile,the lanostanes dehydrosulphurenic acid(8),15a-acetyldehydrosulphurenic acid(12),13 and 14 exhibited poor permeability.Transport features of these compounds were consistent with their pharmacokinetic behaviors in rats.This study could also be helpful in predicting the intestinal absorption of A.cinnamomea in human. 展开更多
关键词 Antrodia cinnamomea Ergostane LANOSTANE TRITERPENOIDS CACO-2
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Identification and determination of (+)-sesamin in Semen Cuscutae by capillary GC and GC-MS 被引量:1
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作者 Yan LI min ye +2 位作者 Hu Wei LIU Xiu Hong JI Yu Ning YAN 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第12期1073-1076,共4页
(+)-Sesamin was found in Semen Cuscutae for the first time. A rapid and simple approach for the analysis of(+)-sesamin in different sources of Semen Cuscutae is proposed, which used GC-FID for the determination of(+)-... (+)-Sesamin was found in Semen Cuscutae for the first time. A rapid and simple approach for the analysis of(+)-sesamin in different sources of Semen Cuscutae is proposed, which used GC-FID for the determination of(+)-sesamin and CC-MS for its identification. The result suggested that this approach could be used to identify Semen Cuscutae from various sources based on the different content of(+)-sesamin in them. 展开更多
关键词 gas chromatography gas chromatography-mass spectrometry (+)-sesamin Semen Cuscutae
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Detection of minor constituents in TongMai Granules using NP×RP off-line twodimensional liquid chromatography coupled with orbitrap mass spectrometry 被引量:1
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作者 Lulu Xu Zhanpeng Shang +4 位作者 Yue Chai Yang Zhang Rong Yu min ye Xue Qiao 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2020年第11期793-803,共11页
TongMai Granules is a Chinese medicine patent drug to treat cardiovascular diseases.It is prepared from the water extract of Dan-shen,Chuan-xiong and Ge-gen.The main compounds of TongMai Granules are isoflavone glycos... TongMai Granules is a Chinese medicine patent drug to treat cardiovascular diseases.It is prepared from the water extract of Dan-shen,Chuan-xiong and Ge-gen.The main compounds of TongMai Granules are isoflavone glycosides,isoflavones,and phenolic acids.However,it is difficult to detect low-polar compounds such as tanshinones and phthalides though they may also contribute to the therapeutic effect.In this work,an off-line two-dimensional chromatography method was developed to enrich the minor constituents in TongMai Granules.The extract was subjected to an SEP-PAK silica SPE column and eluted with petroleum ether,ethyl acetate–methanol(6:1,v/v),and methanol,successively.The three fractions were then analyzed using ultra-high performance liquid chromatography coupled with orbitrap mass spectrometry(UHPLC/orbitrap-MS).The isoflavones from Ge-gen,phenolic acids from Dan-shen and phthalides from Chuan-xiong were distributed in different fractions.A total of 131 compounds,including 59 from Ge-gen,26 from Dan-shen,43 from Chuan-xiong,and 3 common ones from Dan-shen and Chuan-xiong were tentatively identified.Among them,26 compounds were identified by comparing with reference standards.This study set a good example for comprehensive analysis of the constituents in traditional Chinese medicine formula. 展开更多
关键词 TongMai Granules Off-line two-dimensional chromatography NP×RP UHPLC/orbitrap-MS
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Chloride Assisted Growth of Aluminum Nitride Nanobelts and Their Enhanced Dielectric Responses
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作者 Ting Xie min ye +4 位作者 Zhi Jiang Yong Qin Yu-cheng Wu Guo-wen Meng Li-de Zhang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2008年第6期586-590,共5页
Aluminum nitride (AlN) nanobelts were successfully synthesized in high yield through a chloride assisted vapor-solid process. X-ray diffraction, transmission electron microscopy, and selected area electronic diffrac... Aluminum nitride (AlN) nanobelts were successfully synthesized in high yield through a chloride assisted vapor-solid process. X-ray diffraction, transmission electron microscopy, and selected area electronic diffraction demonstrate that the as-prepared nanobelts are pure, structurally uniform and single crystalline, and can be indexed to hexagonal wurtzite structure. The micro observations show that there exist no defects in the obtained nanobelts. The growth direction of the nanobelts is along [0001]. The frequency spectra of the relative dielectric constant and of the dielectric loss were measured in the frequency range of 50 Hz to 5 MHz. Analysis of these spectra indicates that the interface in samples has great influence on the dielectric behavior of samples. As compared with AlN micropowders, AlN nanobelts have much higher relative dielectric constant, especially at low frequencies at room temperature. 展开更多
关键词 Aluminum nitride NANOBELT Chloride assisted growth Dielectric property
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Preliminary Study on Rooting Promotion Activity of 33 Species of Plant Extracts
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作者 Jing WANG Xia LIU +4 位作者 Lin LIU Chun XIAO min ye Liming FAN Yougui ZHA 《Plant Diseases and Pests》 CAS 2012年第3期32-34,共3页
[ Objective ] The paper was to study the rooting promotion activity of plant extracts, so as to lay the foundation for development of natural source of roo- fing reagent with high efficiency, safety and environment fr... [ Objective ] The paper was to study the rooting promotion activity of plant extracts, so as to lay the foundation for development of natural source of roo- fing reagent with high efficiency, safety and environment friendship. [Method] Using mung bean rooting method, the rooting promotion effects of 33 plant extracts on mung bean section were studied. [Result] When the concentration was 1 mg/mL, Eupatorium adenophorum (stem and leaf), Cryptomeriafortunei (stem and leaf), Pinus yunnanensis (stem), Pinus yunnanensis (leaf), Rhododendron simsii (leaf), Pinus armandii (leaf), Litchi chinensis (pericarp), P/nus armandiifruit (fruit) and Alnus cremastogyne (leaf) showed strong promotion effect on rooting of mung bean sections, and the rooting promotion rate reached over 100% ; the roo- ting promotion effect ofE. adenophorum (stem and leaf) was the strongest, reaching(1068.42 +7.87)%, which was extremely higher than the extracts of other plants. [Conclusion] E. adenophorum (stem and leaf), C. fortunei (stem and leaf), P. yunnanens/s (stem), P. yurmanens/s (leaf), R. simsii (leaf), P. armandii (leaf), L. chinensis (pericarp), P. armandiifruit (fruit) and A. cremastogyne (leaf) all contained substances with st/ong rooting promotion effect, which could be further used for development of natural rooting reagent. 展开更多
关键词 Botanical pesticide Rooting reagent Biological screening
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Metabolites identification and quantification of antcin H in mice tumors after oral administration of the anticancer mushroom Antrodia camphorata
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作者 Zi-Wei Li Shuai Ji +4 位作者 Bin Li Shuang Wang yew-min Tzeng Xue Qiao min ye 《TMR Modern Herbal Medicine》 2018年第2期1-11,共11页
Objective: Antrodia camphorata (AC), a precious medicinal mushroom in Taiwan, is popularly used for adjuvant cancer therapy. This paper aims to clarify the metabolites which are present in tumor tissues after oral ... Objective: Antrodia camphorata (AC), a precious medicinal mushroom in Taiwan, is popularly used for adjuvant cancer therapy. This paper aims to clarify the metabolites which are present in tumor tissues after oral administration of AC in Sarcoma-180 tumor-bearing mice, as well as their contents in tumors. Methods: Tumors of Sarcoma-180 tumor-bearing mice were obtained at 1 h and 4 h after oral administration of AC extract, and the metabolites in the tumor homogenate samples were characterized using UHPLC-orbitrap/MS analysis. Then, a fully validated LC-MS/MS method was developed for quantitative analysis of the most abundant compounds in tumor tissues, namely (25R/S)-antcin H. Results: A total of 33 compounds were characterized in tumor homogenate samples including 28 prototypes of triterpenoids and 5 metabolites. Among them, (25R)-antcin H and (25S)-antcin H had the highest contents of 2.03 and 0.66 μg/g tumor tissues for the 1 h group, and 2.04 and 0.59 μg/g tumor tissues for the 4 h group, respectively. It was obvious that (25R)-antcin H had higher tumor affinity than (25S)-antcin H, since the content of (25R)-antcin H was lower than that of (25S)-antcin H in AC extract (P 〈 0.01). Conclusion: Triterpenoids can enter tumor tissues after oral administration of AC. Particularly, (25R)-antcin H showed higher exposure to tumor than (25S)-antcin H. These compounds could contribute to the anticancer activities of AC. 展开更多
关键词 Antrodia camphorata Antcin H METABOLITE ANTICANCER LC-MS/MS
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“逆传心包”刍议
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作者 罗金丽 王亚运 +5 位作者 杨映映 李青伟 周凌 闵叶 赵林华 仝小林 《南京中医药大学学报》 北大核心 2025年第4期421-424,共4页
“温邪上受,首先犯肺,逆传心包”是温病致病的一般规律,历代医家对“逆传心包”一句看法不一,尤以其中“逆”字最为关键。仝小林教授提出,心主神明,心包与心其气相通,心受邪由心包代受,叶天士所提“逆传心包”,实为温邪顺传于脑。将流... “温邪上受,首先犯肺,逆传心包”是温病致病的一般规律,历代医家对“逆传心包”一句看法不一,尤以其中“逆”字最为关键。仝小林教授提出,心主神明,心包与心其气相通,心受邪由心包代受,叶天士所提“逆传心包”,实为温邪顺传于脑。将流脑作为本底疾病,可与卫气营血传变的典型阶段一一对应。结合顶焦理论,认为“心主神明”的功能更侧重于现代解剖意义上的脑。将中医传统温病辨治思路与现代医学有机结合,揭示疾病本质,把握病机核心,从新角度解析“逆”字,探讨其真正含义,对明确其内涵并探索温病发展规律、指导温病辨证治疗具有重要意义。 展开更多
关键词 逆传心包 《温热论》 顶焦 流行性脑脊髓膜炎 顺传于脑 叶天士
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海上风电机组叶片海运叠放支架结构
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作者 李云龙 闵烨 +3 位作者 张璟 马宇轩 杜建国 闫中杰 《船舶工程》 北大核心 2025年第S2期149-153,共5页
[目的]海上风力发电机组叶片长且柔,导致海运空间存在占地大和运输成本高等问题,所受外载荷相比于陆上叶片运输更复杂。[方法]针对海上大容量的机组叶片,开发设计叶片海运叠放支架结构来保障叶片的安全,依托叠放功能,节约运输空间,对降... [目的]海上风力发电机组叶片长且柔,导致海运空间存在占地大和运输成本高等问题,所受外载荷相比于陆上叶片运输更复杂。[方法]针对海上大容量的机组叶片,开发设计叶片海运叠放支架结构来保障叶片的安全,依托叠放功能,节约运输空间,对降本增效起到比较大的作用。运用ANSYS软件,针对某海上项目10 MW风电机组87 m叶片支架结构进行仿真计算,主要包括叶片叠放支架强度分析、支架连接销轴和销孔强度分析以及工装连接螺栓强度分析。[结果]结果表明:叶片海运叠放支架全面考虑叶片质量、风载荷、浪载荷和海运三方向加速度;采用Joint连接准确高效模拟销轴连接,提高计算效率;叶根和叶尖支架整体整体位移云图分布较合理,位置为最上方叶片叶根端部;整体应力云图分布较合理,局部存在应力集中,结构最大应力超过材料许用应力且屈服区域很小时,可以通过塑性应变来判定结果;叶根支架连接销轴结构考虑弯曲强度和剪切强度,主要由弯曲强度控制,工装连接螺栓包括工装与叶根支架螺栓、工装连接螺栓,工装连接螺栓等效应力最大。[结论]研究成果可为海上风电机组叶片叠放支架结构设计提供一定参考。 展开更多
关键词 海上风电叶片 海运叠放支架结构 支架销轴及螺栓 强度分析
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海上漂浮式风-光-波多能互补系统水池试验与仿真一致性验证
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作者 闵烨 李云龙 +1 位作者 马宇轩 张坤鹏 《船舶工程》 北大核心 2025年第S2期9-15,共7页
[目的]旨在通过水池试验,对海上漂浮式风-光-波多能互补系统缩比模型进行试验验证。[方法]结合理论分析、数值模拟和物理模型试验的综合评估方法,通过模拟实际海洋环境中的风、浪、流等条件,评估海上漂浮式风-光-波多能互补系统缩比模... [目的]旨在通过水池试验,对海上漂浮式风-光-波多能互补系统缩比模型进行试验验证。[方法]结合理论分析、数值模拟和物理模型试验的综合评估方法,通过模拟实际海洋环境中的风、浪、流等条件,评估海上漂浮式风-光-波多能互补系统缩比模型在正常工况和极端工况下的性能和响应特性,对比有无波浪能装置对系统运动响应及稳性影响,验证浮体在舱室破损后的总体运动响应特性。[结果]结果表明:多能互补系统缩尺模型运动响应和结构载荷与水池试验测量值的总体趋势保持一致,验证了数值一体化仿真结果的可靠性和准确性;随着波高增大,半潜式平台运动响应的离散程度显著提升,验证了波浪载荷对浮体低频振荡特性的主导作用,千瓦级波浪能装置不足以引发表征性的质心偏移或浮体稳性参数的实质性改变。[结论]试验结果验证了设计方案的有效性,可为海上漂浮式风-光-波多能互补系统的设计提供科学和可靠的技术支持,为后续的工程设计和优化提供指导。 展开更多
关键词 漂浮式多能互补 水池试验 波浪能装置 破舱工况
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礁灰岩地质下重力锚基础的承载特性
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作者 张坤鹏 闵烨 +3 位作者 黄佳 蔡英鹏 马宇轩 罗国滔 《船舶工程》 北大核心 2025年第S1期850-858,共9页
[目的]为探究重力锚在礁灰岩地质条件下的承载特性,[方法]采用ABAQUS有限元分析软件基于礁灰岩的力学特性,对传统重力锚和带裙板重力锚的承载特性进行数值模拟分析。[结果]结果表明,带裙板重力锚在所有摩擦因数工况下均表现出优于传统... [目的]为探究重力锚在礁灰岩地质条件下的承载特性,[方法]采用ABAQUS有限元分析软件基于礁灰岩的力学特性,对传统重力锚和带裙板重力锚的承载特性进行数值模拟分析。[结果]结果表明,带裙板重力锚在所有摩擦因数工况下均表现出优于传统重力锚的承载性能,尤其是在摩擦因数较低时,裙板设计显著提高了承载力。但随着摩擦因数的增大,带裙板的设计优化效果逐渐减弱。所以在高锚岩摩擦因数下,是否增加裙板对重力锚的承载能力影响不大。[结论]研究结果为礁灰岩地质条件下重力锚基础的设计提供了理论依据。 展开更多
关键词 礁灰岩地质 重力锚 有限元分析 承载特性
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Effects of Chloramphenicol Prednisone Liniment on Anti-inflammatory and Anti-pruritic Responses and Skin Barrier Function in an Acute Eczema Mouse Model
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作者 min ye Faying YUE +1 位作者 Shengxin ZHANG Yong XIANG 《Medicinal Plant》 2025年第6期72-74,79,共4页
[Objectives]To observe the effects of chloramphenicol prednisone liniment on anti-inflammatory and anti-pruritic responses and skin barrier function in an acute eczema mouse model and explore its potential underlying ... [Objectives]To observe the effects of chloramphenicol prednisone liniment on anti-inflammatory and anti-pruritic responses and skin barrier function in an acute eczema mouse model and explore its potential underlying mechanism.[Methods]Twenty-four female SPF-grade ICR mice were randomly and equally assigned to three groups:the blank control group,the acute eczema group,and the chloramphenicol prednisone liniment group according to the random number table method,with 8 mice per group.Except for the blank control group,the acute eczema model was established by applying 2,4-dinitrochlorobenzene(DNCB)to the right dorsal area.On day 10(d10),0.1 mL of normal saline was administered to the modeling site in both the blank control group and the acute eczema group,whereas chloramphenicol prednisone liniment was applied to the positive drug group.Medication was applied twice daily in all three groups for a total duration of 14 d.Sixty minutes following the final administration of the drug,the development of eczema in mice was visually assessed,and the severity of skin lesions was scored.Trans-epidermal water loss(TEWL)was measured using a multifunctional skin tester.Experiments inducing and alleviating pruritus were performed to compare the frequency of mice licking their bodies,the latency period before pruritus onset,and the duration of pruritus episodes.Levels of histamine and substance P(SP)in the lesion tissues were quantified using enzyme-linked immunosorbent assay(ELISA).[Results]Compared to the acute eczema group,the chloramphenicol prednisone liniment group exhibited a prolonged latency period of pruritus,an increased inhibition rate,and a shortened duration of pruritus.Additionally,there was a significant reduction in the frequency of mice licking their bodies,as well as in six eczema severity indicators:redness and swelling,scratch marks,papules,blisters,exudation or erosion at the lesion site,and the degree of skin swelling.Furthermore,levels of TEWL,histamine,and SP were also significantly decreased(P<0.05).[Conclusions]Chloramphenicol prednisone liniment exhibits anti-inflammatory and anti-pruritic properties.Its mechanism of action may involve the inhibition of mast cell activation within the lesion tissues of eczema model mice,thereby reducing the release of histamine and other active substances.This process alleviates inflammatory damage associated with eczema and contributes to the restoration of skin barrier function. 展开更多
关键词 Chloramphenicol prednisone liniment Acute eczema model Anti-inflammatory and anti-pruritic Mast cells Histamine Skin barrier function
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Clinical Observation of the Treatment of Postherpetic Neuralgia by External Application of Self-prepared Chinese Prescription Decoction Combined with Gabapentin and Cotton Moxibustion
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作者 min ye Shengxin ZHANG +1 位作者 Fengqin ZHANG Yong XIANG 《Medicinal Plant》 2025年第1期62-63,共2页
[Objectives]To discuss the curative effect of the external application of self-prepared Chinese prescription decoction combined with gabapentin and cotton moxibustion on postherpetic neuralgia(PHN)and analyze its mech... [Objectives]To discuss the curative effect of the external application of self-prepared Chinese prescription decoction combined with gabapentin and cotton moxibustion on postherpetic neuralgia(PHN)and analyze its mechanism.[Methods]96 patients with PHN were divided into the control group(group A)and observation group(group B)(n=48).In group A,the patients were given gabapentin orally and treated by cotton moxibustion.In group B,the patients were treated by the external application of self-prepared Chinese prescription decoction on the basis of the above basic treatment.The total effective rate,apparent time and recurrence rate of the two groups were compared.[Results]The cure rate(72.91%)and total effective rate(95.83%)of patients in group B were higher than those in group A(54.16%,83.33%).The average apparent time[(5.79±1.40)d]and recurrence rate(5.97%)of patients in group B were significantly lower than those in group A[(7.03±4.37)d,10.45%],and the difference between the two groups was statistically significant(P<0.05).[Conclusions]The external application of self-prepared Chinese prescription decoction combined with gabapentin and cotton moxibustion therapy had a significant curative effect and low recurrence rate. 展开更多
关键词 Herpes zoster Neuralgia self-designed Chinese prescription decoction Cotton moxibustion therapy Curative effect
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Characterization of two highly specific O-rhamnosyltransferases involved in the biosynthesis of steroidal saponins from Paris polyphylla var.yunnanensis
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作者 Jia-Jing Zhou Zi-Long Wang +4 位作者 Meng Zhang Yang-Oujie Bao Guo-Wei Chang Yun-Gang Tian min ye 《Chinese Chemical Letters》 2025年第11期436-440,共5页
Steroidal saponins are major bioactive compounds of the medicinal plant Paris polyphylla var.yunnanensis.In this work,two O-rhamnosyltransferases Pp Rha GT1 and Pp Rha GT2 with strict substrate specificity were charac... Steroidal saponins are major bioactive compounds of the medicinal plant Paris polyphylla var.yunnanensis.In this work,two O-rhamnosyltransferases Pp Rha GT1 and Pp Rha GT2 with strict substrate specificity were characterized from this plant.These enzymes could catalyze the synthesis of paris saponinsⅡandⅦ,and realized semi-biosynthesis of a series of paris steroidal saponins in tobacco leaves.Molecular dynamics simulation revealed the substrate specificity of Pp Rha GT1 was due to interactions between the 2-O-rhamnosyl group and surrounding amino acids particularly S382 and E383. 展开更多
关键词 Paris polyphylla var.yunnanensis GLYCOSYLTRANSFERASE Paris saponinⅡ Paris saponinⅦ BIOSYNTHESIS
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Effects of Huanglian Jiedu Decoction on Pain Behaviors in Rat Models of Postherpetic Neuralgia
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作者 min ye Shengxin ZHANG +1 位作者 Faying YUE Yong XIANG 《Medicinal Plant》 2025年第4期37-38,92,共3页
[Objectives]To observe the effects of Huanglian Jiedu Decoction on pain behaviors in rat models of postherpetic neuralgia(PHN)and analyze potential mechanisms.[Methods]Twenty SD rats with PHN models induced by intrapl... [Objectives]To observe the effects of Huanglian Jiedu Decoction on pain behaviors in rat models of postherpetic neuralgia(PHN)and analyze potential mechanisms.[Methods]Twenty SD rats with PHN models induced by intraplantar injection of 50μL(6×106)varicella-zoster virus(VZV)into the left hind paw were randomly divided into two groups(n=10 each)using a random number table:the model group(PHN group)and the Huanglian Jiedu Decoction group.From day 7 after inoculation,the Huanglian Jiedu Decoction group received oral gavage of Huanglian Jiedu Decoction twice daily for 14 days,while the PHN group received an equal volume of 0.9%saline.Thermal withdrawal latency(TWL)and mechanical withdrawal threshold(MWT)were measured at 1,4,7,14,and 21 d after inoculation.Pain-related behaviors(vocalization,scratching,and licking/biting of the hind paw)were recorded.[Results]Compared with the PHN group,the Huanglian Jiedu Decoction group exhibited significantly prolonged TWL and increased MWT at days 14 and 21(P<0.05).At day 4 post-inoculation,both groups showed marked pain-related behaviors(e.g.,vocalization,scratching,licking/biting).These behaviors persisted until day 21 in the PHN group but significantly decreased in the Huanglian Jiedu Decoction group at days 14 and 21(P<0.05).[Conclusions]Huanglian Jiedu Decoction reduces pain sensitivity and alleviates pain-related behaviors in PHN model rats.The mechanism may involve elevating pain thresholds and decreasing pain conduction velocity. 展开更多
关键词 Huanglian Jiedu Decoction Postherpetic neuralgia(PHN) Pain-related behaviors Pain threshold
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用小波变换讨论地震中的多普勒现象 被引量:1
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作者 李启成 闵也 何书耕 《吉林大学学报(地球科学版)》 CAS CSCD 北大核心 2021年第3期909-918,共10页
地震中多普勒效应可以确定地震的破裂面等,说明对多普勒效应的研究有实际意义,但目前确定地震中是否存在多普勒效应的方法并不成熟。在研究多普勒效应空间分布规律的基础上,提出用小波变换确定地震中是否存在多普勒效应的方法。选择位... 地震中多普勒效应可以确定地震的破裂面等,说明对多普勒效应的研究有实际意义,但目前确定地震中是否存在多普勒效应的方法并不成熟。在研究多普勒效应空间分布规律的基础上,提出用小波变换确定地震中是否存在多普勒效应的方法。选择位于汶川地震断层滑动前方的若干台站对台站最初时段的地震记录进行小波变换时,发现随着震中距的增加,小波谱高频幅值明显大于小波谱低频幅值;说明虽然存在介质对地震波的吸收衰减作用,但多普勒效应的存在仍使得小波谱高频幅值增大。选择与汶川地震断层垂直方位的若干台站对台站最初时段的地震记录进行小波变换时,发现随着震中距的增加,小波谱高频幅值迅速降低,震中距大到一定程度后低频部分的小波谱幅值会明显大于高频部分的小波幅值;说明在该方向上,介质对地震波的高频吸收衰减起主要作用,没有发生多普勒效应。 展开更多
关键词 多普勒效应 地震 频率 小波变换 汶川地震
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用随机有限断层方法模拟2016-11-13新西兰M_W7.8地震 被引量:1
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作者 李启成 何书耕 +1 位作者 闵也 郑新娟 《大地测量与地球动力学》 CSCD 北大核心 2019年第12期1237-1242,共6页
在未来大地震发震构造已知的前提下,提出用经验公式确定大地震断层长度、宽度、地震矩和滑动分布等参数,并用随机有限断层方法预测未来大地震。用随机有限断层方法模拟2016-11-13新西兰M W7.8地震的12个基岩台站地震动时程和反应谱,并... 在未来大地震发震构造已知的前提下,提出用经验公式确定大地震断层长度、宽度、地震矩和滑动分布等参数,并用随机有限断层方法预测未来大地震。用随机有限断层方法模拟2016-11-13新西兰M W7.8地震的12个基岩台站地震动时程和反应谱,并用模拟的频谱幅值与记录频谱幅值平均比值确定模拟误差。结果表明,在周期为0~10 s的范围内,模拟误差在0.92~1.08之间,不同频率模拟误差的标准差变化范围不超过1。95%的置信区间宽度随频率无明显变化,模拟结果反映了地震动记录的平均效果。用准随机方法重新获取新西兰大地震断层初始破裂点和位错滑动分布,模拟地震动并计算模拟误差随频率的变化,得到与最初模型相似的结论,从而进一步证实了本文提出的获取震源参数并用随机有限断层方法预测未来大地震的可靠性,且其特别适用于大地震远场模拟。 展开更多
关键词 地震 有限断层 随机方法 模拟
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用相干体属性开展断层识别 被引量:7
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作者 席桂梅 何书耕 +2 位作者 闵也 孙颍川 李启成 《西北地质》 CAS CSCD 北大核心 2019年第1期244-249,共6页
利用地震属性可以提高三维地震解释的精度和速度,并且节约成本,有利于矿井安全生产。在重点对相干体属性做出阐述和分析的基础上,以永城煤矿为研究区,首先正确合理选用相干体属性的最优参数,然后将相干体属性应用于实例获取数据体,再从... 利用地震属性可以提高三维地震解释的精度和速度,并且节约成本,有利于矿井安全生产。在重点对相干体属性做出阐述和分析的基础上,以永城煤矿为研究区,首先正确合理选用相干体属性的最优参数,然后将相干体属性应用于实例获取数据体,再从属性数据体中提取出沿层切片,最后对地震数据进行相干体处理后得到了地震剖面。与不经相干处理的的地震原始剖面相比较,经相干处理的地震剖面更清晰地反映了地层和断层。相干体方法是有前途的地震剖面解释方法。 展开更多
关键词 地震属性 参数 相干体
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半潜式浮式风机系统湿拖过程动力响应研究 被引量:2
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作者 李亚杰 闵烨 +3 位作者 张坤鹏 刘利琴 余勇军 孟春蕾 《舰船科学技术》 北大核心 2022年第18期116-121,共6页
研究浮式风力机系统整体湿拖的运动及拖缆张力,建立浮式风力机系统的水动力模型,基于三维势流理论计算浮式基础的水动力。考虑风、浪、流环境载荷,计算拖航过程浮式基础运动、风机法兰倾角、机舱加速度、拖缆张力等关键参数,分析缆长、... 研究浮式风力机系统整体湿拖的运动及拖缆张力,建立浮式风力机系统的水动力模型,基于三维势流理论计算浮式基础的水动力。考虑风、浪、流环境载荷,计算拖航过程浮式基础运动、风机法兰倾角、机舱加速度、拖缆张力等关键参数,分析缆长、有义波高、谱峰周期等参数对计算结果的影响。结果表明,在给定的环境参数范围内,浮式风机运动符合限制条件;拖缆越短相同环境参数下拖缆张力越大,600 m及以上缆长的拖缆张力相对稳定,受波浪参数影响较小。最后给出不同缆长作业的波浪参数限制条件,为浮式风机整体湿拖作业提供参考。 展开更多
关键词 浮式风机 整体湿拖 风机运动 拖缆力
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