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乙型肝炎病毒相关慢加急性肝衰竭评分模型及检验参数对诊断及预后影响的研究进展 被引量:1
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作者 吴悦嘉 谢青 +2 位作者 刘玉盒 陈小勇 闫雪华 《世界华人消化杂志》 CAS 2023年第6期207-213,共7页
乙肝相关慢加急性肝衰竭(hepatitis B virus relatedacute-on-chronic liver failure,HBV-ACLF)是肝衰竭的常见类型,可发生在慢性乙型病毒性肝炎或肝硬化代偿期或失代偿期的基础上,其病情进展快速,常合并肝、脑、心、肾、凝血等多器官... 乙肝相关慢加急性肝衰竭(hepatitis B virus relatedacute-on-chronic liver failure,HBV-ACLF)是肝衰竭的常见类型,可发生在慢性乙型病毒性肝炎或肝硬化代偿期或失代偿期的基础上,其病情进展快速,常合并肝、脑、心、肾、凝血等多器官功能衰竭的临床综合征,病死率极高.美国胃肠病学会(American Gastroenterological Association,ACG)将其定义为具有潜在可逆性疾病,早期诊断,规范治疗,将极大影响其预后.近年来,一些新的评分模型及生物标志物的临床应用,有效提高了对HBV-ACLF的诊断及预后判断.本文对目前临床应用较广的评分模型及检验参数进行了梳理,进一步探讨其对HBV-ACLF的诊断和预后影响的价值. 展开更多
关键词 慢加急性肝衰竭 乙型肝炎病毒 诊断价值
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Bibliometric analysis of research relating to refractive cataract surgery over a 20-year period:from 2003 to 2022 被引量:2
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作者 xiao-yong chen Qian-Ru Wu +2 位作者 Min-Yue Xie Di Zhang Chun Zhang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第10期1692-1701,共10页
AIM:To investigate the research trend on refractive cataract surgery,compare the contributions of different countries,institutions,journals,and authors in the past 20y,and explore its potential research hotspots.METHO... AIM:To investigate the research trend on refractive cataract surgery,compare the contributions of different countries,institutions,journals,and authors in the past 20y,and explore its potential research hotspots.METHODS:All publications were extracted relating to refractive cataract surgery from 2003 to 2022 from Web of Science.Document types were limited to original articles and reviews,and the language was limited to English.Quantitatively and qualitatively of the publications were analyzed through Microsoft Excel and GraphPad Prism.VOSviewer and CiteSpace were used for bibliometric and visualized analysis.RESULTS:A total of 2090 publications were enrolled.The United States contributed the most publications(434,20.8%),followed by China(345,16.5%)and England(163,7.80%).Publications from the United States were cited more frequently(9552 citations)with the highest H-index of 48.China ranked second in the total number of publications,the papers were not cited that frequently(3237 citations),and the H-index ranked sixth(H-index=29).Journal of Cataract and Refractive Surgery published the most papers(333,15.9%),and the University of London had the highest number of publications(75,3.59%).Dick HB from Germany published the most papers.Corneal astigmatism-related research,cataract surgery methodrelated research,postoperative visual-quality relate to research,and postoperative complications-relate research are the hotspots in this field.The most significant limitation was that the database was updated frequently and the latest publications were not included.CONCLUSION:The bibliometric analysis shows a brief summarization of the contribution of the authors,institutions,countries,and journals.Corneal astigmatism,cataract surgery method,postoperative visual-quality and postoperative complications related researches have become the emerging hotspots,which can give a direction in the future researches. 展开更多
关键词 bibliometric analysis cataract surgery refractive cataract surgery corneal astigmatism
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Vicariance and monsoon as drivers of diversification of nemacheilid loaches(Teleostei:Cypriniformes)around the Hengduan Mountains of China
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作者 Rui Min Ya-Hui Zhao +2 位作者 Bin Kang xiao-yong chen Jun-Xing Yang 《Zoological Research》 SCIE CSCD 2023年第5期936-938,共3页
DEAR EDITOR,High mountainous terrains facilitate the diversification of biota by providing a variety of opportunities for isolation(Favre et al.,2015).Within the Nemacheilidae family of loaches,the highly diverse Nema... DEAR EDITOR,High mountainous terrains facilitate the diversification of biota by providing a variety of opportunities for isolation(Favre et al.,2015).Within the Nemacheilidae family of loaches,the highly diverse Nemacheilini tribe is a polyphyletic group,with extensive distribution across the Indian and Eurasian plates(Chen et al.,2019;Sgouros et al.,2019). 展开更多
关键词 CYPRINIFORMES mountainous Eurasian
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Macular edema after cataract surgery in diabetic eyes evaluated by optical coherence tomography 被引量:11
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作者 xiao-yong chen Wen-Jun Song +1 位作者 Hong-Yuan Cai Lin Zhao 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2016年第1期81-85,共5页
AIM:To assess quantitative changes of the macula in diabetic eyes after cataract surgery using optical coherence tomography(OCT)and to estimate the incidence of development or worsening of macular edema(ME)in dia... AIM:To assess quantitative changes of the macula in diabetic eyes after cataract surgery using optical coherence tomography(OCT)and to estimate the incidence of development or worsening of macular edema(ME)in diabetic eyes with or without pre-existing ME.·METHODS:In this prospective,observational study,92eyes of 60 diabetic patients who underwent cataract surgery were evaluated before surgery and 1,3mo after surgery using OCT.Macular thickness was measured with OCT at nine macular subfields defined by the 9zones early treatment of diabetic retinopathy study(ETDRS),as well as total macular volume obtained by OCT at 1,3mo after surgery were compared with baseline features obtained before surgery.In addition,the incidence of development or worsening of ME was analyzed in diabetic eyes with or without pre-existing ME.·R ESULTS:The central subfield mean thickness increased 21.0μm and 25.5μm at 1,3mo follow-up,respectively(〈0.01).The average thickness of inner ring and outer ring increased 14.2μm and 9.5μm at 1mo,18.2μm and 12.9μm at 3mo.Central-involved ME developed in 12 eyes at 3mo,including 4 eyes with preexisting central-involved and 8 eyes with pre-existing non-central involved ME.Pre-existing diabetic macular edema(DME)was significantly associated with centralinvolved ME development(〈0.001).·C ONCLUSION:A statistically significant increase could be detected in the central subfield as well as perifoveal and parafoveal sectors though the increase was mild.And eyes with pre-operative DME prior to cataract surgery are at higher risk for developing central-involved ME. 展开更多
关键词 macular edema DIABETES optical coherence tomography cataract surgery
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A review of the Cypriniform tribe Yunnanilini Prokofiev,2010 from China,with an emphasis on five genera based on morphologies and complete mitochondrial genomes of some species 被引量:4
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作者 Li-Na Du Jian Yang +2 位作者 Rui Min xiao-yong chen Jun-Xing Yang 《Zoological Research》 SCIE CAS CSCD 2021年第3期310-334,共25页
The loach tribe Yunnanilini from China is reviewed here using morphological characters and complete mitochondrial genomes of select species.Molecular data suggest that the tribe Yunnanilini is not monophyletic and can... The loach tribe Yunnanilini from China is reviewed here using morphological characters and complete mitochondrial genomes of select species.Molecular data suggest that the tribe Yunnanilini is not monophyletic and can be divided into three clades.Species of the Yunnanilus nigromaculatus group form an independent genus and are placed in Eonemachilus.In the phylogenetic tree,Y.jinxiensis clusters with Paranemachilus genilepis,and Y.pulcherrimus clusters with Micronemacheilus cruciatus,indicating that Y.jinxiensis and Y.pulcherrimus belong to Paranemachilus and Micronemacheilus,respectively.Based on while Y.jinxiensis and Y.pulcherrimus,are placed in Paranemachilus and Micronemacheilus,respectively.Yunnanilus niulanensis and Y.qujinensis are treated as junior synonyms of Eonemachilus caohaiensis.Eonemachilus,Micronemacheilus,and Yunnanilus are show short separation between anterior and posterior nostrils.The genera can be distinguished from each other by mouth structure,lateral line and cephalic lateral-line canals,and papillae on median part of both lips.The anterior and posterior nostrils of Heminoemacheilus and Paranemachilus are closely set.Paranemachilus and Micronemacheilus are distinguished by cheeks covered with scales and lips with papillae,respectively.Our phylogenetic tree and morphological characters support Traccatichthys as a valid genus,which can be distinguished from Micronemacheilus by anterior and posterior nostrils closely set(vs.clearly separated).Four species are placed in Traccatichthys. 展开更多
关键词 Eonemachilus Heminoemacheilus Micronemacheilus Paranemachilus Yunnanilus Taxonomy
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Three-dimensional morphology of the Sinocyclocheilus hyalinus(Cypriniformes: Cyprinidae) horn based on synchrotron X-ray microtomography 被引量:2
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作者 You HE xiao-yong chen +1 位作者 Ti-Qao XIAO Jun-Xing YANG 《Zoological Research》 CAS CSCD 北大核心 2013年第5期I0020-I0026,共7页
Sinocyclocheilus is a cave-dwelling cyprinid genus endemic to southwest China. Several species possess a conspicuous horn on their head, which has been suggested as a constructive troglomorphic trait but lacks substan... Sinocyclocheilus is a cave-dwelling cyprinid genus endemic to southwest China. Several species possess a conspicuous horn on their head, which has been suggested as a constructive troglomorphic trait but lacks substantial evidence. We used non- invasive, high spatial resolution synchrotron X-ray microtomography to investigate the three-dimensional (3D) morphology of the horn of Sinocyclocheilus hyalinus, one of eight such troglobiotic species. 3D renderings demonstrated the osteological components, which were comprised of a rear wall comprised of the supraoccipital bone, a remaining frontal wall with numerous fenestrae, and the bottom continuous with the parietal and epiotic. A horn cavity occurred within the horn. The fenestrae in the frontal wall were continuous in the horn cavity and showed elaborate channeling, and were, connected to the cranial cavity by soft tissue. We tentatively called this configuration the "otocornual connection" due to its anatomic and putative functional similarity to the otolateralic connection in clupeids and loricariids, which provide an indirect pathway to enhance perception of underwater sound signals. This study provides a functional morphology context for further histological and physiological investigations of such horn structures in Sinocyclocheilus cavefish, and we suggest that the horn might enhance acoustic perception to compensate for visual loss in subterranean life, which warrants future physiological examination as lab-reared S. hyalinus become available. 展开更多
关键词 Sinocyclocheilus hyalinus CAVEFISH HORN Troglomorphism Synchrotron X-ray microtomography
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Tilt and decentration with various intraocular lenses: A narrative review 被引量:2
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作者 xiao-yong chen Yu-chen Wang +2 位作者 Tian-Yao Zhao Zi-Zhen Wang Wei Wang 《World Journal of Clinical Cases》 SCIE 2022年第12期3639-3646,共8页
We find that tilt and decentration of intraocular lens (IOL) commonly cause visualquality deterioration after cataract surgery. Multiple factors affect IOL tilt anddecentration in the pre-, mid-, and post-operation ph... We find that tilt and decentration of intraocular lens (IOL) commonly cause visualquality deterioration after cataract surgery. Multiple factors affect IOL tilt anddecentration in the pre-, mid-, and post-operation phases. Moreover, the tilt anddecentration of 1-piece IOL are less correlated with internal ocular HOAs thanthose of 3-piece IOL. Aspherical IOLs are more sensitive to decentration or tiltthan spherical IOLs. Furthermore, the optical performance of toric IOLs with anaccurate axis remains stable irrespective of tilt and decentration. The opticalquality of asymmetric multifocal IOLs varies significantly after decentration andtilt in different directions. The image quality enhances or deteriorates in thedirection of the decentered IOL. An extended depth of focus IOL can achievegood visual acuity in the distant, intermediate, and near range. Additionally, itstilt and decentration have less impact on the vision than bifocal and trifocal IOL.This is the first review that compares the effect of IOL tilt and decentration onimage quality for various IOL designs. The result indicates that a deeperunderstanding of tilt and decentration of various IOLs can help achieve a bettervisual effect to visually improve refractive cataract surgery. 展开更多
关键词 Intraocular lens Tilt and decentration High order aberration Visual quality
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Morphological analysis of the Chinese Cipangopaludina species(Gastropoda; Caenogastropoda: Viviparidae) 被引量:1
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作者 Hong-Fa LU Li-Na DU +2 位作者 Zhi-Qiang LI xiao-yong chen Jun-Xing YANG 《Zoological Research》 CAS CSCD 北大核心 2014年第6期510-527,共18页
Viviparidae are widely distributed around the globe, but there are considerable gaps in the taxonomic record. To date, 18 species of the viviparid genus Cipangopaludina have been recorded in China, but there is substa... Viviparidae are widely distributed around the globe, but there are considerable gaps in the taxonomic record. To date, 18 species of the viviparid genus Cipangopaludina have been recorded in China, but there is substantial disagreement on the validity of this taxonomy. In this study, we described the shell and internal traits of these species to better discuss the validity of related species. We found that C. ampulliformis is synonym of C. lecythis, and C. wingatei is synonym of C. chinensis, while C. ampullacea and C. fluminalis are subspecies of C. lecythis and C. chinensis, respectively. C. dianchiensis should be paled in the genus Margarya, while C. menglaensis and C. yunnanensis belong to genus Mekongia. Totally, this leaves 11 species and 2 subspecies recorded in China. Based on whether these specimens' spiral whorl depth was longer than aperture depth, these species or subspecies can be further divided into two groups, viz. chinensis group and cathayensis group, which can be determined from one another via the ratio of spiral depth and aperture depth, vas deferens and number of secondary branches of vas deferens. Additionally, Principal Component Analysis indicated that body whorl depth, shell width, aperture width and aperture length were main variables during species of Cipangopaludina. A key to all valid Chinese Cipangopaludina species were given. 展开更多
关键词 Cipangopaludina GASTROPODA Bellamyinae ANATOMY TAXONOMY CHINESE
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A new species of sisorid catfish of the genus Exostoma from the Salween drainage, Yunnan, China 被引量:1
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作者 xiao-yong chen William J. Poly +1 位作者 David Catania Wan-Sheng Jiang 《Zoological Research》 CAS CSCD 2017年第5期291-299,共9页
A new species of the sisorid catfish genus Exostoma Blyth, 1860 was collected from two hill-stream tributaries of the Nujiang (Salween River) drainage in Gaoligong Mountain, south-western Yunnan Province, China from... A new species of the sisorid catfish genus Exostoma Blyth, 1860 was collected from two hill-stream tributaries of the Nujiang (Salween River) drainage in Gaoligong Mountain, south-western Yunnan Province, China from 2003 to 2006 and from two tributaries of the Salween River in Cangyuan County Lingcang Prefecture, Yunnan Province, China (in 2007) and in Yongde County, Lingcang Prefecture, Yunnan Province, China (in 2015). Exostoma gaoligongense sp. nov. is the 10th species of the genus and is most similar to E. vinciguerrae in morphology but can be distinguished by pelvic fin reaching anus vs. not reaching; maxillary barbels just reaching or slightly surpassing pectoral-fin origin vs. surpassing pectoral-fin origin or even reaching posterior end of gill membrane; abdominal vertebrae 23-25 vs. 25-27; length of dorsal fin/dorsal to adipose distance 90.3%-287.0% vs. 59.2-85.7. A key to Exostoma spp. is provided. 展开更多
关键词 Glyptosterninae SISORIDAE Nujiang Gaoligong Mountain YUNNAN
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A new genus and species of disc-bearing Labeoninae(Teleostei:Cypriniformes)from Guangxi,China 被引量:1
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作者 Zhi-Bang Wang xiao-yong chen Lan-Ping Zheng 《Zoological Research》 SCIE CAS CSCD 2022年第3期409-412,共4页
DEAR EDITOR,Guigarra cailaoensis sp.nov.,a new genus and species of Labeoninae,was collected from Guangxi Zhuang Autonomous Region,China.It differs from all other genera within Labeoninae by a unique combination of th... DEAR EDITOR,Guigarra cailaoensis sp.nov.,a new genus and species of Labeoninae,was collected from Guangxi Zhuang Autonomous Region,China.It differs from all other genera within Labeoninae by a unique combination of the following characters:(1)rostral cap smooth with posterior margin slightly serrated;(2)upper lip well developed and covering most of upper jaw;(3)gular disc present with crescentic torus. 展开更多
关键词 slightly China. TORUS
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Three-dimensional morphology of the Sinocyclocheilus hyalinus(Cypriniformes:Cyprinidae)horn based on synchrotron X-ray microtomography
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作者 You HE xiao-yong chen +1 位作者 Ti-Qao XIAO Jun-Xing YANG 《Zoological Research》 SCIE CAS CSCD 北大核心 2013年第S05期128-134,共7页
Sinocyclocheilus is a cave-dwelling cyprinid genus endemic to southwest China.Several species possess a conspicuous horn on their head,which has been suggested as a constructive troglomorphic trait but lacks substanti... Sinocyclocheilus is a cave-dwelling cyprinid genus endemic to southwest China.Several species possess a conspicuous horn on their head,which has been suggested as a constructive troglomorphic trait but lacks substantial evidence.We used non-invasive,high spatial resolution synchrotron X-ray microtomography to investigate the three-dimensional(3D)morphology of the horn of Sinocyclocheilus hyalinus,one of eight such troglobiotic species.3D renderings demonstrated the osteological components,which were comprised of a rear wall comprised of the supraoccipital bone,a remaining frontal wall with numerous fenestrae,and the bottom continuous with the parietal and epiotic.A horn cavity occurred within the horn.The fenestrae in the frontal wall were continuous in the horn cavity and showed elaborate channeling,and were,connected to the cranial cavity by soft tissue.We tentatively called this configuration the“otocornual connection”due to its anatomic and putative functional similarity to the otolateralic connection in clupeids and loricariids,which provide an indirect pathway to enhance perception of underwater sound signals.This study provides a functional morphology context for further histological and physiological investigations of such horn structures in Sinocyclocheilus cavefish,and we suggest that the horn might enhance acoustic perception to compensate for visual loss in subterranean life,which warrants future physiological examination as lab-reared S.hyalinus become available. 展开更多
关键词 Sinocyclocheilus hyalinus CAVEFISH HORN Troglomorphism Synchrotron X-ray microtomography
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Five newly recorded Cyprinid fish (Teleostei: Cypriniformes) in Myanmar
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作者 Tao Qin Zhi-Ying chen +4 位作者 Lu-Lu Xu Paing Zaw Yunn Mi Mi Kyaw Kyaw Win Maung xiao-yong chen 《Zoological Research》 CAS CSCD 2017年第5期300-309,共10页
Freshwater fish from the Putao and Myitkyina areas were collected in three ichthyofaunal surveys of the Mall Hka River and tributaries in and around Khakaborazi National Park and Hponkanrazi Wildlife Sanctuary, Kachin... Freshwater fish from the Putao and Myitkyina areas were collected in three ichthyofaunal surveys of the Mall Hka River and tributaries in and around Khakaborazi National Park and Hponkanrazi Wildlife Sanctuary, Kachin State, from 2014-2016. Tor yingjiangensis Chen et Yang 2004, Tor qiaojiensis Wu et al. 1977, Garra qiaojiensis Wu et al. 1977, Garra bispinosa Zhang 2005, and Schizothorax oligolepis Huang 1985, originally described from the upper Irrawaddy (Ayeyarwaddy) River in China, are first reported herein as new records to Myanmar. Counts, measurements, descriptions, photographs, and distributions of the specimens of the five newly recorded species are provided. 展开更多
关键词 New record CYPRINIDAE Mali Hka River Irrawaddy Myanmar
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What is the destiny of a threatened fish, Ptychobarbus chungtienensis, now that non-native weatherfishes have been introduced into Bita Lake, Shangri-La?
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作者 Wan-Sheng JIANG Tao QIN +5 位作者 Wei-Ying WANG Ya-Peng ZHAO Shu-Sen SHU Wei-Hong SONG xiao-yong chen Jun-Xing YANG 《Zoological Research》 CAS CSCD 2016年第5期275-280,共6页
Biological invasion is a pervasive negative force of global change, especially in its effects on sensitive freshwater ecosystems. Even protected areas are usually not immune. Ptychobarbus chungtienensis is a threatene... Biological invasion is a pervasive negative force of global change, especially in its effects on sensitive freshwater ecosystems. Even protected areas are usually not immune. Ptychobarbus chungtienensis is a threatened freshwater fish now almost confined to Bita Lake, in the Shangri-La region of Yunnan province, China. Its existence is threatened by the introduction of non-native weatherfishes (Misgumus anguillicaudatus and Paramisgurnus dabryanus) by an unusual method known as 'prayer animal release' Periodic surveys revealed the ratio of invasive weatherfishes to P. chungtienensis has been increasing since the former species was first recorded from the lake in August, 2009. Ptychobarbus chungtienensis shows low genetic diversity in the relict Lake Bita population. Weatherfishes, however, have highly successful survival strategies. The degree of dietary overlap between the species is alarming and perhaps critical if food is found to be a limiting factor. 展开更多
关键词 Biological invasion Threatened fish Prayer animal release Genetic diversity DIETARY
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Morphological and molecular studies on Garra imberba and its related species in China
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作者 Wei-Ying WANG Wei ZHOU +1 位作者 Jun-Xing YANG xiao-yong chen 《Zoological Research》 CAS CSCD 北大核心 2014年第1期20-32,共13页
Garra imberba is widely distributed in China. At the moment, both Garra yiliangensis and G. hainanensis are treated as valid species, but they were initially named as a subspecies of G. pingi, a junior synonym of G. i... Garra imberba is widely distributed in China. At the moment, both Garra yiliangensis and G. hainanensis are treated as valid species, but they were initially named as a subspecies of G. pingi, a junior synonym of G. imberba. Garra alticorpora and G. nujiangensis also have similar morphological characters to G. imberba, but the taxonomic statuses and phylogenetic relationships of these species with G. imberba remains uncertain. In this study, 128 samples from the Jinshajiang, Red, Nanpanjiang, Lancangjiang, Nujiang Rivers as well as Hainan Island were measured while 1 mitochondrial gene and 1 nuclear intron of 24 samples were sequenced to explore the phylogenetic relationship of these five species. The results showed that G. hainanensis, G. yiliangensis, G. alticorpora and G. imberba are the same species with G. imberba being the valid species name, while G. nujiangensis is a valid species in and of itself. 展开更多
关键词 Garra imberba TAXONOMY MORPHOLOGY Molecular phylogeny
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Hardening and Optimizing of the Black Gold Thin Film as the Absorption Layer for Infrared Detector
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作者 Dong-pei Qian Chuan-gui Wu +4 位作者 Yao Shuai Wen-bo Luo Qiang-xiang Peng xiao-yong chen Wan-li Zhang 《Optics and Photonics Journal》 2013年第2期281-283,共3页
This paper reports on the study of the black gold thin film as the absorption layer in the near infrared spectrum. The fabrication of the black gold thin film was achieved by a thermal evaporation technique in N2 atmo... This paper reports on the study of the black gold thin film as the absorption layer in the near infrared spectrum. The fabrication of the black gold thin film was achieved by a thermal evaporation technique in N2 atmosphere. Different evaporation conditions were attempted to optimize the absorbance of the black gold coating, especially the atmosphere pressure and the mass of evaporation source. The long-standing problem of black gold’s adhesion with the substrate was solved by fuming 502 superglues into the black gold layer, which had almost no impact on the absorbance performance. Layers produced at N2 atmosphere of 3×103 Pa show an absorbance exceeding0.9 inthe near infrared. 展开更多
关键词 BLACK GOLD 502 FUMING ABSORPTION Layer
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Habitat fragmentation alters predator satiation of acorns 被引量:3
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作者 Xin Tong Yu-Xuan Zhang +2 位作者 Rong Wang Moshe Inbar xiao-yong chen 《Journal of Plant Ecology》 SCIE CSCD 2017年第1期67-73,共7页
Aims Acorn weevils(Curculio spp.),endoparasitic granivorous insects,impede recruitment of fagaceous trees,and in turn affect community structure and ecosystem functioning.Previous studies have made considerable progre... Aims Acorn weevils(Curculio spp.),endoparasitic granivorous insects,impede recruitment of fagaceous trees,and in turn affect community structure and ecosystem functioning.Previous studies have made considerable progress in elucidating local factors that contribute to seed predation by acorn weevils,but it is still not clear how habitat configurations interplay with local factors in influencing Curculio predation.In this study,we assessed the roles of crop size,landscape configurations(area and isolation)and their interactions on the predation rate of seeds by acorn weevils.Methods We studied acorn weevils feeding on the seeds of Castanopsis sclerophylla(Fagaceae)on two peninsulas and nine islands with varying areas and isolation levels in the Thousand-island Lake in Chun’an County,Zhejiang Province of China.Overall,crop size was estimated for 130 trees and predation status was assessed for 26207 seeds from these trees during two years.Generalized linear mixed models were performed to clarify how island area and isolation interplayed with crop size to determine predation rate on a single tree.Important Findings A negative relationship was detected between crop size and seed predation rate,indicating predator satiation at the tree level.This suggests that acorn weevils tend to stay sedentary once they have arrived at a suitable habitat.Habitat fragmentation had significant effects on seed predation such that predation rate was higher on larger,less isolated islands.Furthermore,the relationship between crop size and predation rate was significantly changed by both island area and isolation.This finding highlighted that the effects of habitat isolation might be overlooked relative to those of habitat loss. 展开更多
关键词 Castanopsis sclerophylla CURCULIO ISOLATION limited dispersal predator satiation
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Effects of water depth on clonal characteristics and biomass allocation of Halophila ovalis (Hydrocharitaceae) 被引量:3
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作者 Na-Na Xu Xin Tong +2 位作者 Po-Kueug Eric Tsang Hong Deng xiao-yong chen 《Journal of Plant Ecology》 SCIE 2011年第4期283-291,共9页
Halophila ovalis is a dioecious seagrass with a wide geographical and water depth range.The objective of this study was to understand its plasticity in clonal characteristics and biomass and also its allocation betwee... Halophila ovalis is a dioecious seagrass with a wide geographical and water depth range.The objective of this study was to understand its plasticity in clonal characteristics and biomass and also its allocation between above-and belowground in seagrass beds at different water depths.Methods Four monospecific H.ovalis beds,Shabei,Xialongwei,Beimu and Yingluo,which have different water depths at maximum tide level(MTL)but otherwise similar environmental conditions,were studied.We measured main clonal characteristics,i.e.horizontal internodal length,branching angle,shoot height,leaf length and width,and rhizome diameter.Above-and belowground biomasses of H.ovalis were also estimated using a harvest method.Important Findings We found no significant differences in coverage,leaf pair density or number of stem nodes per square meter between the four study sites.However,horizontal internodal length,leaf length,width,rhizome diameter and shoot height all increased significantly with the increases in water depth from 2-to 9-m MTL and decreased when the water depths were greater than 9-m MTL.No significant difference in above-or belowground biomass between the seagrass beds was found.However,the ratio of above-to belowground biomass was significantly higher in the shallowest site compared to the other three seagrass beds,indicating that more biomass was stored belowground in deeper water.The results demonstrated plastic responses in clonal characteristics and biomass allocation in H.ovalis across the water depth gradient. 展开更多
关键词 Halophila ovalis water depth gradient RHIZOME SHOOT biomass allocation SEAGRASS
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The prevalence of freezing of gait in Parkinson’s disease and in patients with different disease durations and severities 被引量:9
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作者 Hong-Liang Ge xiao-yong chen +6 位作者 Yuan-Xiang Lin Ting-Juan Ge Liang-Hong Yu Zhang-Ya Lin Xi-Yue Wu De-Zhi Kang chen-Yu Ding 《Chinese Neurosurgical Journal》 CSCD 2020年第2期92-102,共11页
Background:The prevalence rates of freezing of gait(FOG)in Parkinson’s disease(PD)vary widely,ranging from 14.0 to 55.1%.Our aim is to calculate the overall prevalence of FOG in all PD patients with different disease... Background:The prevalence rates of freezing of gait(FOG)in Parkinson’s disease(PD)vary widely,ranging from 14.0 to 55.1%.Our aim is to calculate the overall prevalence of FOG in all PD patients with different disease durations and severities.Methods:Using Medline/PubMed/Embase,we carried out a systematic literature search for studies reporting the PD and clinically relevant FOG.Results:After primary screening,a total of 35 studies were identified and further analyzed for inclusion into the analysis,and 29 studies fulfilled the quality criteria and included in this meta-analysis.The overall prevalence of FOG in PD was 39.9%(95%CI 35.3-44.5%).The FOG identified by the freezing of gait questionnaire item 3 may be more prevalent(43.8%,95%CI 38.5-49.1%)than the FOG identified by the Unified Parkinson’s Disease Rating Scale item 14(36.0%,95%CI 29.0-43.1%).Disease duration and severity are both the clinical features associated with the FOG.The highest FOG prevalence rate in PD patients was seen in patients with disease durations≥10 years,at 70.8%,followed that of PD patients with disease durations≥5 years(53.3%),and PD patients with disease durations<5 years(22.4%).FOG presented in 28.4%of PD patients with Hoehn and Yahr staging(H&Y)score≤2.5,and in 68.4%of PD patients with H&Y score≥2.5.Conclusion:This meta-analysis confirms that the prevalence of FOG in PD is considerable,and highlights the need for accurate identification of FOG in PD. 展开更多
关键词 PREVALENCE FREEZING GAIT Parkinson disease
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High genetic diversity and strong differentiation in dramatically fluctuating populations of Zostera japonica(Zosteraceae):implication for conservation 被引量:2
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作者 Kai Jiang Po-Keung Eric Tsang +1 位作者 Na-Na Xu xiao-yong chen 《Journal of Plant Ecology》 SCIE CSCD 2018年第5期789-797,共9页
Aims Seagrasses provide a variety of ecosystem goods and services,but they are subjected to frequently anthropogenic disturbances.In this study,we genotyped samples collected from Zostera japonica mead-ows with dramat... Aims Seagrasses provide a variety of ecosystem goods and services,but they are subjected to frequently anthropogenic disturbances.In this study,we genotyped samples collected from Zostera japonica mead-ows with dramatic fluctuations in the area in order to understand the distribution of genetic variation within and among populations.Methods We collected samples from eight extant populations along coastal areas of southern China.Ten polymorphic microsatellites were adopted to genotype the samples.Parameters of genetic diversity and differentiation were calculated with general software.Important Findings High levels of genetic diversity were found in the studied populations,suggesting that the effective population size has not decreased signifi-cantly,which was supported by no signs of recent bottlenecks.High genetic diversity reflects an important role of sexual seedling recruit-ment in Z.japonica populations.We found a significant relationship between genetic differentiation and the shortest sea surface distance of populations,suggesting that ocean currents play a critical role in shap-ing the genetic structure of Z.japonica populations.STRUCTURE soft-ware analysis clustered the eight populations into two groups:western and eastern populations separated by the Qiongzhou Strait/Leizhou Peninsula,hinting that there was very limited gene flow through the narrow strait in this marine plant.Four populations had high contribu-tion diversity and,thus,high priority for in situ conservation. 展开更多
关键词 SEAGRASS Zostera japonica Genetic diversity Genetic differentiation Microsatellites
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Demographic Genetic Structure of Cryptomeria japonica var. sinensis in Tianmushan Nature Reserve, China 被引量:1
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作者 Yan chen Shu-Zhen Yang +3 位作者 Ming-Shui Zhao Bi-Ye Ni Liang Liu xiao-yong chen 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2008年第9期1171-1177,共7页
Genetic changes over space and time provide insights into the relative roles of evolutionary factors in shaping genetic patterns within plant populations. However, compared with spatial genetic structure, few studies ... Genetic changes over space and time provide insights into the relative roles of evolutionary factors in shaping genetic patterns within plant populations. However, compared with spatial genetic structure, few studies have been conducted on genetic changes over time. In this study, we used six polymorphic microsatellite loci to assess genetic variation of six size-classes of the population of Liushan, Cryptomeriajaponica var. sinensis, in the Tianmushan National Nature Reserve, whose origin was debatable. The mean number of alleles per locus and expected heterozygosity were 4.583 and 0.5999 respectively, lower than other conifers with the same life history characteristics. FST was 0.0024-0.003, and the pairwise test revealed no significant differentiation in any pair of size classes. Significant heterozygosity excesses were detected in five size classes except the oldest one, indicating bottleneck event(s). The above results support the hypothesis that Tianmushan population was introduced and followed by natural regeneration. 展开更多
关键词 Cryptomeriajaponica var. sinensis founder effect genetic variation microsatellites size class.
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