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基于四种常用机器学习的梭梭(Haloxylon ammod-endron(C.A.Mey)Bunge)适宜生境分布研究 被引量:1
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作者 朱妮 郭彦龙 《生态科学》 CSCD 2023年第4期190-199,共10页
梭梭Haloxylon ammodendron (C.A.Mey) Bunge是适应中亚荒漠生境的耐寒、抗旱、耐盐碱C4植物,预测该物种地理分布范围以及未来不同气候变化情景下该物种适宜生境分布的变化,对于我国荒漠区生态环境保护具有重要意义。利用收集的梭梭分... 梭梭Haloxylon ammodendron (C.A.Mey) Bunge是适应中亚荒漠生境的耐寒、抗旱、耐盐碱C4植物,预测该物种地理分布范围以及未来不同气候变化情景下该物种适宜生境分布的变化,对于我国荒漠区生态环境保护具有重要意义。利用收集的梭梭分布数据与33个环境因子,基于四种常用的机器学习算法组成的组合模型对该物种适宜生境在我国西北干旱区的分布进行了预测。结果表明:(1)不同的模型算法的结果在空间上具有较高的一致性,但其分布细节具有一定的差异性。(2)梭梭在我国的适宜生境面积约为0.91×10^(6) km^(2),主要分布在新疆的准噶尔盆地和塔里木盆地边缘,甘肃河西走廊地区,内蒙古巴丹吉林、乌兰布和、腾格里沙漠和库布齐沙漠的西部,青海省柴达木盆地等地区。(3)未来气候变化对该物种适宜生境分布的影响取决于升温幅度,但是在大部分的增温情景中,该物种的适宜生境变化较小。(4)高适宜生境面积为0.19×10^(6) km^(2),应该作为梭梭原生产地保护以及人工种植的重点区域。(5)集成多模型结果的组合物种分布模型能够在一定程度上减少模型的不确定性,增加模型的精度。在环境条件限制性较高的干旱区,加入土壤因素能够有效提高物种分布模型的建模科学性和合理性。 展开更多
关键词 梭梭(Haloxylon ammodendron(c.a.Mey)Bunge 物种分布 机器学习 组合模型 荒漠物种
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A new coumarin from Wikstroemia indica (L.) C.A.Mey 被引量:1
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作者 Yang Chen Wen Wei Fu +3 位作者 Li Xin Sun Qia Wang Wei Qi Hua Yu 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第5期592-594,共3页
A new coumarin was obtained from the stems and roots of Wikstroemia indica (L.) C. A. Mey. Its structure was elucidated as methyl 3-(2-hydroxy-4-(7-hydroxy-6-methoxy-2-oxo-2H-chromen-3-yloxy) phenyl) propanoate ... A new coumarin was obtained from the stems and roots of Wikstroemia indica (L.) C. A. Mey. Its structure was elucidated as methyl 3-(2-hydroxy-4-(7-hydroxy-6-methoxy-2-oxo-2H-chromen-3-yloxy) phenyl) propanoate by spectroscopic methods. 展开更多
关键词 Wikstroemia indica (L.) c.a. Mey COUMARIN Structure elucidation
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A new triterpene saponin from Panax japonicus C.A.Meyer var major(Burk.) C.Y.Wu et K.M.Feng 被引量:5
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作者 Hong Zhao Lin Shi +3 位作者 Jia Qing Cao Wei Li Xia Wen Yu Qing Zhao 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第10期1216-1218,共3页
One new Iriterpene saponin was isolated from Panaxjaponicus C. A. Meyer var major (Burk.) C. Y. Wu et K. M. Feng, and established as oleanolic acid 3-O-[β-D-glucopyranosyl-(1 →2)-β-D-glucuronopyranosyl-6'-O-n-... One new Iriterpene saponin was isolated from Panaxjaponicus C. A. Meyer var major (Burk.) C. Y. Wu et K. M. Feng, and established as oleanolic acid 3-O-[β-D-glucopyranosyl-(1 →2)-β-D-glucuronopyranosyl-6'-O-n-butyl ester] which showed mod- erate antitumor activities against the A2780 cells and OVCAR-3 cells. Its structure was established by means of spectral data, particularly NMR, including HSQC and HMBC techniques. 展开更多
关键词 Oleanolic acid 3-O-[β-D-glucopyranosyl-(1 2)-β-D-glucuronopyranosyl-6'-O-n-butyl ester] Antitumor Panax japonicus C. A.Meyer vat major (Burk) C Y wu et K. M Feng Triterpene saponin
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Study on Surface Sterilization Method for Tissue Culture of Haloxylon ammodendron(C.A.Mey.) Bunge Seeds 被引量:1
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作者 Dong WANG Guiping ZHAO 《Agricultural Biotechnology》 CAS 2012年第3期26-28,共3页
[ Objective ] The aim was to select appropriate sterilization methods and explants for tissue culture of Haloxylon ammodendron ( C. A. Mey. ). [Method] H. ammodendron (C. A. Mey. ) seeds were used as experimental ... [ Objective ] The aim was to select appropriate sterilization methods and explants for tissue culture of Haloxylon ammodendron ( C. A. Mey. ). [Method] H. ammodendron (C. A. Mey. ) seeds were used as experimental materials to investigate the sterilization results of different sterilization treatments and the effect of different seed sizes on the survival rate of aseptic seedlings. [ Result] Sterilization of H. ammodendron ( C.A. Mey. ) seeds achieved the best result by using 75% alcohol for 15 min and 0.1% mercuric chloride for 8 min. Seeds with diameter φ 〉 2.0 mm were used as explants and achieved relatively high surviv- al rate of aseptic seedlings, which reached above 65%. [ Conclusion] This study established a surface sterilization method for tissue culture of H. ammodendron ( C. A. Mey. ) Bunge seeds. 展开更多
关键词 Haloxylon ammodendron (C. A. Mey. Bunge Sterilization methods Tissue culture
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C.A.摘录 V.9 4(1981)
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《中国胶粘剂》 CAS 1982年第3期70-82,共13页
永基粘合剂2036 31962 低能固化的聚合物.Am.Dyest Rep 1980,69(10),19-21,45(英文).使用以丙烯酸酯为基料的乳液聚合物如:Rhoplex LE-1126作为纺织品的层压和植绒的粘合剂,革除了昂贵的烘箱固化操作。
关键词 乙烯 烯烃 丁苯橡胶 V.9 4 c.a 层压制品
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Y.M.C.A.与Y.W.C.A.
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作者 姜志伟 《语言教育》 1996年第12期91-91,共1页
Y.M.C.A.(Young Men’s Christian Association)意思是“基督教青年会”。该组织是在乔治·威廉斯爵士(Sir George Williams)倡导下,于1844年在英国伦敦建立的以通过团体活动和公民训练发扬基督徒高尚品德为宗旨的跨教派的非政治性... Y.M.C.A.(Young Men’s Christian Association)意思是“基督教青年会”。该组织是在乔治·威廉斯爵士(Sir George Williams)倡导下,于1844年在英国伦敦建立的以通过团体活动和公民训练发扬基督徒高尚品德为宗旨的跨教派的非政治性组织。Williams 是伦敦一家布店店员,后来成为店主。起初该组织是一个俱乐部,拥有12名青年成员,他们提出的口号是:“提高布店和其他行业青年的灵性修养”。这个俱乐部迅速推广到英国各地。1850年传到澳大利亚,1851年传到北美洲,其后在北美洲各地得到空前发展。 展开更多
关键词 基督教青年会 非政治性 Y.M.c.a Y.W.c.a 威廉斯 基督教女青年会 团体活动 生活辅导 德夫 学位资格
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K.C.A.法脱硫通过技术鉴定
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作者 林桂就 《广西化工》 1989年第3期60-60,共1页
广西化工研究所开发的新型脱硫剂——K.C.A.它在小氮肥厂使用时仍以氨水为脱硫吸收介质。K.C.A.法在玉林化肥厂进行了一年多的工业性应用试验;迄今,全国已有十三个省(区)四十多家小氮肥厂由使用对苯二酚、MQ、MSQ、FeSO_4·7H_2O及... 广西化工研究所开发的新型脱硫剂——K.C.A.它在小氮肥厂使用时仍以氨水为脱硫吸收介质。K.C.A.法在玉林化肥厂进行了一年多的工业性应用试验;迄今,全国已有十三个省(区)四十多家小氮肥厂由使用对苯二酚、MQ、MSQ、FeSO_4·7H_2O及栲胶等氨水液相催化法改用K.C.A.法,只要脱硫设备合理且使用得法,大都获得较满意的效果。 展开更多
关键词 脱硫剂 氮肥 K.c.a 脱硫
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General and Specific Combining Abilities of Pacific Oyster(Crassostrea gigas)and Fujian Oyster(C.angulata)for Growth,Survival and Thermal Tolerance of Their Reciprocal Hybrids 被引量:1
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作者 JIANG Gaowei XU Chengxun LI Qi 《Journal of Ocean University of China》 2025年第1期238-248,共11页
A crossbreeding program was established in 2019 to address the declining Crassostrea gigas harvests caused by Pacific Oyster Mortality Syndrome(POMS).As a part of the program,this study was performed to estimate the g... A crossbreeding program was established in 2019 to address the declining Crassostrea gigas harvests caused by Pacific Oyster Mortality Syndrome(POMS).As a part of the program,this study was performed to estimate the genetic structure underlying phenotypic variation.Fifteen complete diallel crossings of C.gigas and C.angulata,comprising 60 full-sib families,were used to evaluate the general combining ability(GCA)and specific combining ability(SCA),as well as genotype and environment interactions for shell height(SH),summer survival(SS),and thermal tolerance(TT)of reciprocal hybrids GA(C.gigas♀×C.angulata♂)and AG(C.angulata♀×C.gigas♂)grown in Rongcheng and Rushan,Shandong Province,China.The results suggested that heterosis of the reciprocal hybrids was evident for SH,SS,and TT.The hybrid GA had larger heterosis than AG in both testing environments,and can be a potential donor in the breeding program.The male C.gigas had better GCA for SH in Rongcheng,whereas male C.angulata was a good general combiner for SS and TT in both Rongcheng and Rushan.The estimate of SCA was much higher than GCA for SH and lower than GCA for TT.To harness both additive and non-additive genetic effects,combination breed-ing could be taken to develop hybrid varieties possessing both thermal tolerance and fast-growing traits.The positive correlations between SH and TT suggested that these traits could be improved simultaneously.The significant G×E interactions demonstrated the importance to undertake site-specific breeding programs in different environments.Overall,this study can provide essential information for developing crossbreeding strategies for the oyster farming industry. 展开更多
关键词 CROSSBREEDING combining ability genotype×environment interaction Crassostrea gigas c.angulata
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Nutritional quality of interspecific backcross between hybrids of Crassostrea gigas×C.angulata and their two parental species
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作者 Chenchen WEI Luping WANG +4 位作者 Xinfeng SUN Wei WANG Guofan ZHANG Li LI Rihao CONG 《Journal of Oceanology and Limnology》 2025年第3期1022-1035,共14页
Oysters are of the most economically important bivalves worldwide.It has high nutritional value and is regarded as a good source of proteins,lipids,glycogen,and amino acids.C.gigas and C.angulata are allopatric congen... Oysters are of the most economically important bivalves worldwide.It has high nutritional value and is regarded as a good source of proteins,lipids,glycogen,and amino acids.C.gigas and C.angulata are allopatric congeneric dominant oysters that are widely cultivated in the northern and southern coast of China,and have shown remarkable differentiation in the nutritional content.Interspecific hybridization and backcross of the two species are effective ways to improve the nutritional quality of the oyster.Sixteen progenies were constructed based on a 4×4 diallel crosses among broodstock of C.gigas(G),C.angulata(A)and their hybrids GA(H)and AG(R).The glycogen,fatty acids,and amino acids performance of these progenies were evaluated in 22 months after fertilization.The glycogen content of AA was significantly lower than that of the other 15 progenies(P<0.05),while only the GH progeny was significantly higher than the GG(P<0.05),with a heterosis value of 21.06%.The backcross progenies GR exhibited significantly higher saturated fatty acids,eicosapentaenoic acid(EPA),and polyunsaturated fatty acids(PUFAs)content than those of GG(P<0.05),and did not show significant differences from AA.The AA showed significantly higher content of total amino acids(TAAs)than GG(P<0.05).The AH progeny displayed significantly higher taurine(Tau)content than GG(P<0.05),and the heterosis value was 27.88%.Therefore,the backcross breeding was shown an effective way to improve the glycogen,fatty acids,and TAAs of GG,and the glycogen of AA.This study provided useful information to characterize the benefits of backcrossing in nutritional quality,which will facilitate the production of differentiated products and increase the efficiency of the oyster industry. 展开更多
关键词 Crassostrea gigas c.angulata interspecific backcross GLYCOGEN fatty acid amino acid
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“More Like a Real Person Walking on a Thin Line”─On the Characterizational Shift of C.Auguste Dupin in Edgar Allan Poe’s Detective Stories
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作者 Biy Bin Feng Huang 《Journal of Literature and Art Studies》 2025年第10期737-749,共13页
This paper aims to examine the characterizational shift of C.Auguste Dupin in Edgar Allan Poe’s detective stories.First,Poe’s detective stories were written when the Enlightenment,which emphasizes Reason,was being e... This paper aims to examine the characterizational shift of C.Auguste Dupin in Edgar Allan Poe’s detective stories.First,Poe’s detective stories were written when the Enlightenment,which emphasizes Reason,was being embedded in the fabric of American culture.Meanwhile,beneath the Enlightenment was also an undercurrent of irrationality.In Poe’s“The Murders in the Rue Morgue”and“The Mystery of Marie Rogêt,”Dupin typifies a flat character standing for Reason/Good.However,in Poe’s“The Purloined Letter,”Dupin has been depicted as a round character;not only is he characterized a lot more vividly but also he bears striking resemblance to his opponent,Minister D.Namely,the dichotomous relationship between them has been erased,and Dupin has been portrayed more like a real person walking on the thin line between Good and Evil.Speaking of dissecting this characterizational shift of Dupin,I believe the key lies in the fact that Poe actually has taken an attitude of openness about Reason and Unreason,and that he has a way with opposing elements.In“The Murders in the Rue Morgue”and“The Mystery of Marie Rogêt,”Poe intends for Reason,represented by Dupin,to keep under control Unreason,represented by the criminals.In such a case,Dupin only needs to be a flat character representing Good/Reason.But in“The Purloined Letter,”Poe intends for Reason/Good and Unreason/Evil to be merged.Under such circumstances,Dupin will conveniently evolve into a round character. 展开更多
关键词 (c.auguste)Dupin (Edgar Allan)Poe the characterization(al shift) detective stories
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CO一步法C.autoethanogenum发酵产乙醇的工艺研究 被引量:5
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作者 徐惠娟 梁翠谊 +4 位作者 许敬亮 何敏超 袁振宏 陈小燕 张宇 《农业工程学报》 EI CAS CSCD 北大核心 2017年第23期246-251,共6页
合成气/CO发酵制备燃料乙醇是一项具有吸引力的新技术,为促进C.autoethanogenum在该技术中的应用,对C.autoethanogenum的乙醇发酵工艺及过程参数进行了研究。结果表明,C.autoethanogenum代谢木糖的产物以乙酸为主,只产生少量乙醇;与无... 合成气/CO发酵制备燃料乙醇是一项具有吸引力的新技术,为促进C.autoethanogenum在该技术中的应用,对C.autoethanogenum的乙醇发酵工艺及过程参数进行了研究。结果表明,C.autoethanogenum代谢木糖的产物以乙酸为主,只产生少量乙醇;与无机氮源相比较,C.autoethanogenum在含有机氮源的培养基中生长迅速,菌体浓度高。在3 L发酵罐中进行C.autoethanogenum的批式发酵试验,采用木糖生长-CO发酵两步法,乙醇主要在CO发酵阶段产生,最高乙醇质量浓度为1.71 g/L;发酵罐经改进之后,采用CO一步法发酵,虽然得到的菌体浓度降低了,但是发酵时间延长,最高乙醇质量浓度达到7.36 g/L,而乙酸质量浓度在整个发酵过程中均低于1.1 g/L。此外,研究发现发酵液的pH值和氧化还原电位ORP与乙酸/乙醇产物分布密切相关,尤其是pH值。上述研究结果可为C.autoethanogenum发酵CO生产乙醇的中试放大提供参考。 展开更多
关键词 乙醇 发酵 一氧化碳 合成气发酵 乙酸 c.autoethanogenum
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毛喉素调控ERK和Akt信号通路促进C2C12成肌细胞分化
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作者 黄柳艳 张文烯 +3 位作者 陈淑雯 余诗美 戴忠 左长清 《中国组织工程研究》 北大核心 2026年第5期1114-1121,共8页
背景:毛喉素是一种从毛喉鞘蕊花中提取到的二萜类天然化合物,对骨骼肌的修复具有重要的调节作用。但毛喉素对C2C12骨骼肌细胞成肌分化的调控作用尚未得到充分探索。目的:研究毛喉素对C2C12成肌细胞系分化的影响,并探讨其潜在的分子机制... 背景:毛喉素是一种从毛喉鞘蕊花中提取到的二萜类天然化合物,对骨骼肌的修复具有重要的调节作用。但毛喉素对C2C12骨骼肌细胞成肌分化的调控作用尚未得到充分探索。目的:研究毛喉素对C2C12成肌细胞系分化的影响,并探讨其潜在的分子机制。方法:在C2C12细胞生长过程中分别加入0,0.1,0.25,0.5,1,5,10,20μmol/L毛喉素进行处理,CCK-8和qRT-PCR检测细胞增殖情况。在诱导C2C12细胞成肌分化过程中分别加入0,0.25,0.5,1μmol/L毛喉素进行处理,免疫荧光染色及qRT-PCR检测C2C12细胞成肌分化状况;Western blot检测影响成肌分化的相关信号通路蛋白的表达水平。结果与结论:①高浓度(>1μmol/L)毛喉素处理后,C2C12细胞的活力下降,细胞增殖被抑制。②与0μmol/L组比较,成肌诱导4 d时,qRT-PCR结果显示毛喉素能够上调Myh2、Myh4、Myomaker的表达,但是下调Myh7的表达;免疫荧光染色结果表明,毛喉素处理后C2C12细胞的融合指数和肌管直径均增加,肌管的数量增多。③Western blot结果表明成肌分化诱导2 d时,毛喉素处理明显抑制细胞外信号调节激酶1/2磷酸化蛋白表达水平,促进蛋白激酶B磷酸化蛋白表达;毛喉素处理会显著上调成肌分化转录因子肌细胞生成素蛋白表达水平。④结果表明,毛喉素可能通过调控细胞外信号调节激酶1/2及蛋白激酶B信号传导促进C2C12骨骼肌细胞成肌分化。 展开更多
关键词 毛喉素 成肌分化 C2C12细胞 ERK1/2 Akt 骨骼肌 肌细胞生成素 细胞增殖
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C.Alisa与王姣bdFF动作起跳出台技术对比分析
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作者 龙春生 薛淑君 《沈阳体育学院学报》 2004年第5期619-622,共4页
分析结果显示:C Alisa的bdFF动作的起跳及出台技术更加合理,其动作的运动学特征更加符合目前国际裁判对bdFF动作的评分理念和标准,即起跳后重心垂直升起高度要高,尽可能的"晚"转体和"快"转体,实现所谓的腾起后尽可... 分析结果显示:C Alisa的bdFF动作的起跳及出台技术更加合理,其动作的运动学特征更加符合目前国际裁判对bdFF动作的评分理念和标准,即起跳后重心垂直升起高度要高,尽可能的"晚"转体和"快"转体,实现所谓的腾起后尽可能的"等待",而在转体中要有明确而清晰的周际间的"分隔"。与C Alisa相比较,王姣在起跳及出台技术的内涵和外部表象特征上存在着一定差距,这种差距是影响后继动作的完成质量及获得较高技评分值的根本原因。 展开更多
关键词 c.alisa 王姣 bdFF动作 跳台滑雪 运动员 起跳出台技术 对比分析 空中技巧 助滑速度 动作完成质量 运动生物力学
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Multi-analytical characterization of Os Draconis:distinguishing authentic samples from fossilized specimens and counterfeits for improved authentication
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作者 Dong-Han Bai Lu Luo +5 位作者 Zi-Hao Zhang Zi Xing Remy Macdonald Shu-Min Chen Qiao-Chu Wang Zhi-Jie Zhang 《Traditional Medicine Research》 2026年第3期36-55,共20页
Background:Os Draconis is an important material in traditional Chinese medicine(TCM).However,its market is saturated with counterfeit products,and the limitations of current identification methods pose a serious threa... Background:Os Draconis is an important material in traditional Chinese medicine(TCM).However,its market is saturated with counterfeit products,and the limitations of current identification methods pose a serious threat to clinical effectiveness and drug safety.This study aims to establish a more accurate and comprehensive authentication system for Os Draconis.Methods:A comprehensive approach was employed to analyze authentic Os Draconis,fossilized Os Draconis,counterfeit products,and lab-prepared modern animal bones.The analytical techniques included ^(14)C dating,electron probe microanalysis(EPMA),polarized light microscopy,X-ray diffraction(XRD),inductively coupled plasma mass spectrometry(ICP-MS),and fourier-transform infrared spectroscopy(FTIR).The study focused on examining the microstructural features and micro-area elemental compositions to identify distinguishing characteristics.Results:Physical identification alone was insufficient to reliably distinguish authentic Os Draconis from its counterfeits.XRD analysis revealed that while hydroxyapatite is the main component in all samples,authentic Os Draconis also contains calcium carbonate and quartz,which were absent in counterfeit and lab-prepared samples.FTIR spectra identified the carbonate ion(CO_(3)^(2-))as a characteristic infrared marker for authentic Os Draconis.ICP-MS analysis showed that Ca and P are the major elements,with a notably high content of Lanthanum(La)among rare earth elements in authentic samples.The EPMA results demonstrated that the Ca/P ratio of authentic Os Draconis is distinct,falling between that of fossilized Os Draconis and counterfeit samples.Conclusion:This study successfully identified several precise markers,including the presence of calcium carbonate,the characteristic CO_(3)^(2-)infrared peak,a high La content,and a specific Ca/P ratio,for the accurate and rapid authentication of Os Draconis.Furthermore,the analysis of its natural porous structure,suitable pore size,and surface area suggests that Os Draconis has significant potential as a natural drug carrier. 展开更多
关键词 Os Draconis ULTRASTRUCTURE ^(14)C dating EPMA XRD ICP-MS FTIR
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替罗非班序贯双抗联合瑞舒伐他汀治疗进展性脑卒中的疗效及对C反应蛋白的影响分析
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作者 杨金凤 董琛 魏玉艳 《中国现代药物应用》 2026年第2期102-104,共3页
目的分析替罗非班序贯双抗联合瑞舒伐他汀对进展性脑卒中的疗效及对C反应蛋白的影响。方法选取进展性脑卒中患者70例,根据治疗方案不同分为两组,各35例。对照组采用双抗(阿司匹林+氯吡格雷)联合瑞舒伐他汀治疗,观察组替罗非班序贯双抗... 目的分析替罗非班序贯双抗联合瑞舒伐他汀对进展性脑卒中的疗效及对C反应蛋白的影响。方法选取进展性脑卒中患者70例,根据治疗方案不同分为两组,各35例。对照组采用双抗(阿司匹林+氯吡格雷)联合瑞舒伐他汀治疗,观察组替罗非班序贯双抗治疗。对比两组治疗效果、C反应蛋白水平、神经功能缺损程度(NIHSS)评分、Barthel指数及不良反应发生率。结果观察组总有效率为88.57%,较对照组的68.57%更高(P<0.05)。治疗后,观察组C反应蛋白(5.28±1.36)mg/L较对照组的(7.85±1.82)mg/L更低(P<0.05)。治疗后,与对照组的(11.36±2.85)、(65.28±11.67)分对比,观察组NIHSS评分(8.25±2.18)分更低,Barthel指数(78.56±12.34)分更高(P<0.05)。两组不良反应发生率对比无差异(P>0.05)。结论替罗非班序贯双抗联合瑞舒伐他汀治疗进展性脑卒中,可降低患者C反应蛋白水平,改善神经功能,提升其日常生活活动能力,且具有一定安全性。 展开更多
关键词 替罗非班 双抗 瑞舒伐他汀 进展性脑卒中 C反应蛋白
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Topical administration of GLP-1 eyedrops improves retinal ganglion cell function by facilitating presynaptic GABA release in early experimental diabetes
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作者 Yu-Qi Shao Yong-Chen Wang +6 位作者 Lu Wang Hang-Ze Ruan Yun-Feng Liu Ti-Hui Zhang Shi-Jun Weng Xiong-Li Yang Yong-Mei Zhong 《Neural Regeneration Research》 2026年第2期800-810,共11页
Diabetic retinopathy is a prominent cause of blindness in adults,with early retinal ganglion cell loss contributing to visual dysfunction or blindness.In the brain,defects inγ-aminobutyric acid synaptic transmission ... Diabetic retinopathy is a prominent cause of blindness in adults,with early retinal ganglion cell loss contributing to visual dysfunction or blindness.In the brain,defects inγ-aminobutyric acid synaptic transmission are associated with pathophysiological and neurodegenerative disorders,whereas glucagon-like peptide-1 has demonstrated neuroprotective effects.However,it is not yet clear whether diabetes causes alterations in inhibitory input to retinal ganglion cells and whether and how glucagon-like peptide-1 protects against neurodegeneration in the diabetic retina through regulating inhibitory synaptic transmission to retinal ganglion cells.In the present study,we used the patch-clamp technique to recordγ-aminobutyric acid subtype A receptor-mediated miniature inhibitory postsynaptic currents in retinal ganglion cells from streptozotocin-induced diabetes model rats.We found that early diabetes(4 weeks of hyperglycemia)decreased the frequency of GABAergic miniature inhibitory postsynaptic currents in retinal ganglion cells without altering their amplitude,suggesting a reduction in the spontaneous release ofγ-aminobutyric acid to retinal ganglion cells.Topical administration of glucagon-like peptide-1 eyedrops over a period of 2 weeks effectively countered the hyperglycemia-induced downregulation of GABAergic mIPSC frequency,subsequently enhancing the survival of retinal ganglion cells.Concurrently,the protective effects of glucagon-like peptide-1 on retinal ganglion cells in diabetic rats were eliminated by topical administration of exendin-9-39,a specific glucagon-like peptide-1 receptor antagonist,or SR95531,a specific antagonist of theγ-aminobutyric acid subtype A receptor.Furthermore,extracellular perfusion of glucagon-like peptide-1 was found to elevate the frequencies of GABAergic miniature inhibitory postsynaptic currents in both ON-and OFF-type retinal ganglion cells.This elevation was shown to be mediated by activation of the phosphatidylinositol-phospholipase C/inositol 1,4,5-trisphosphate receptor/Ca2+/protein kinase C signaling pathway downstream of glucagon-like peptide-1 receptor activation.Moreover,multielectrode array recordings revealed that glucagon-like peptide-1 functionally augmented the photoresponses of ON-type retinal ganglion cells.Optomotor response tests demonstrated that diabetic rats exhibited reductions in visual acuity and contrast sensitivity that were significantly ameliorated by topical administration of glucagon-like peptide-1.These results suggest that glucagon-like peptide-1 facilitates the release ofγ-aminobutyric acid onto retinal ganglion cells through the activation of glucagon-like peptide-1 receptor,leading to the de-excitation of retinal ganglion cell circuits and the inhibition of excitotoxic processes associated with diabetic retinopathy.Collectively,our findings indicate that theγ-aminobutyric acid system has potential as a therapeutic target for mitigating early-stage diabetic retinopathy.Furthermore,the topical administration of glucagon-like peptide-1 eyedrops represents a non-invasive and effective treatment approach for managing early-stage diabetic retinopathy. 展开更多
关键词 diabetic retinopathy glucagon-like peptide-1 inhibitory synaptic transmission miniature inhibitory postsynaptic currents NEURODEGENERATION NEUROPROTECTION patch-clamp recording protein kinase C signaling pathway visual function
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茶树炭疽菌 Colletotrichum gloeosporioides和C.acutatum的生物学特性比较及致病毒性初探 被引量:7
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作者 沈大航 乔文君 +2 位作者 刘智 童华荣 陈应娟 《西南农业学报》 CSCD 北大核心 2018年第5期980-985,共6页
【目的】从重庆地区茶树种植区内的感病茶树叶片上分离纯化到2种能侵染茶树的炭疽菌,经形态学和多基因序列分析鉴定为C.acutatum和C.gloeosporioides,其中C.acutatum为本实验室从茶树上分离保存的新记录种。【方法】比较该2种炭疽菌的... 【目的】从重庆地区茶树种植区内的感病茶树叶片上分离纯化到2种能侵染茶树的炭疽菌,经形态学和多基因序列分析鉴定为C.acutatum和C.gloeosporioides,其中C.acutatum为本实验室从茶树上分离保存的新记录种。【方法】比较该2种炭疽菌的一般生物学特性。【结果】C.gloeosporioides的生长速度明显快于C.acutatum,但2种菌均能在多种培养基上进行生长,且同是以PDA和PSA为最适生长培养基,而菌生长的最适宜温度均在25~28℃之间,在40℃时仍能进行生长,菌丝致死温度在60~65℃之间。致病毒素研究发现2种茶树炭疽菌均能产生有致病力的外毒素,引起类似于自然状态下病原菌侵染形成的叶片坏死、萎焉等症状,但相比之下C.gloeosporioides的毒素活性更强。【结论】研究结果为后续茶树炭疽菌的致病性差异及其致病机制研究奠定了基础,也为炭疽菌的有效防治开辟了新的路径。 展开更多
关键词 茶树 C.gloeosporioides c.acutatum 生物学特性 毒素活性
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一个艰辛的、呼之欲出的广告新时代——来自C.A.A.A.的启示
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作者 沈毅 《声屏世界(广告人)》 2008年第2期78-78,共1页
现在广告公司赖以生存的核心竞争力是:自己对商业(消费业)理解的能力。有了这个能力,创作才会有爆破力;有了这个能力,才能赢得企业的尊敬。
关键词 广告文化 c.a.A.A 中国广告 媒介购买 行业协会领导 公司创始人 网络界 运用资本 电通 品牌理论
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美国战俘保护制度的双重性标准探析——以《§ 2005.Prisoners of war 50 App.U.S.C.A.§ 2005》为视角
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作者 朱海梦 《西安政治学院学报》 2015年第6期100-105,共6页
近几场局部战争中,美军频发虐囚事件,引发世界高度关注。为削减虐囚事件带来的负面影响,平复美军内部厌战情绪,美军开始反思自己的战俘政策。2005年出台的《§2005.Prisoners of war 50 App.U.S.C.A.§2005》,对战俘身份确认、... 近几场局部战争中,美军频发虐囚事件,引发世界高度关注。为削减虐囚事件带来的负面影响,平复美军内部厌战情绪,美军开始反思自己的战俘政策。2005年出台的《§2005.Prisoners of war 50 App.U.S.C.A.§2005》,对战俘身份确认、战俘待遇、赔偿提请程序作出了一系列改进,但与《关于战俘待遇之日内瓦公约》及后续出台相关国际公约中规定的战俘保护制度相比,美军战俘保护制度的双重性标准彰显无遗。 展开更多
关键词 战俘 《§2005.Prisoners of war 50 App.U.S.c.a.§2005》 日内瓦公约 双重性
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The beginning of acupuncture in Washington,D.C.and Maryland:an interview with Dr.Yeh-chong Chan 被引量:6
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作者 Arthur Yin Fan Zivi Fan 《Journal of Integrative Medicine》 SCIE CAS CSCD 2013年第3期220-228,共9页
Dr. Yeh-chong Chan (Y.C. Chan) is one of the earliest acupuncturists in the United States (US). He served for seven years in the first acupuncture center in the US, which was established in Washington, D.C. in 197... Dr. Yeh-chong Chan (Y.C. Chan) is one of the earliest acupuncturists in the United States (US). He served for seven years in the first acupuncture center in the US, which was established in Washington, D.C. in 1972. In 1979, he moved the clinic to Rockville, Maryland and continued to practice acupuncture there for over 30 years. He is a well-known licensed acupuncturist (LAc), one of the developers of the acupuncture profession, and a scholar of acupuncture and traditional Chinese medicine (TCM). He has treated two US Governors (In the US, the title Governor refers to the chief executive of each state or insular territory and the political and ceremonial head of the state.) and many sports stars. He is the author of books entitled Acupuncture Practice in the United States, 展开更多
关键词 ACUPUNCTURE the United States MARYLAND Washington DC interview as topic history of medicine Dr. Yeh-chong Chan (Y.C. Chan)
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