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Cytological Events during Zygote Formation of the Fern Ceratopteris thalictroides

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Journal of Integrative Plant Biology 2010年第3期52卷 254-264页

作者： jian-guo cao quan-xi wang nai-ying yang Wen-Mei Bao College of Life and Environment Science Shanghai Normal University Shanghai 200234 China

The cytological events, including nuclear fusion, digestion of male organelles and rebuilding of the plasmalemma and cell wall, during zygote formation of the fern Ceratopteris thalictroides （L.） Brongn. are described based on the observations of transmission electron microscopy. When the spermatozoid enters the egg and contacts the cytoplasm, the male chromatin relaxes continually. The microtubular ribbon （MTr） is separated from the male nucleus and then an envelope reappears around the male nucleus. During nuclear fusion, the egg nucleus becomes highly irregular and extends some nuclear protrusions. It is proposed that the protrusions fuse with the male nucleus actively. After nuclear fusion the irregular zygotic nucleus contracts gradually. It becomes spherical before the zygote divides. The male chromatin is identifiable as fibrous structure in the zygotic nucleus in the beginning, but it gradually becomes diffused completely. The male organelles, including the MTr, multilayered structure, flagella and the male mitochondria are finally digested in the zygotic cytoplasm. Finally a new plasmalemma and cell wall are formed outside the protoplast. The organelles in the zygote are rearranged, which produces a horizontal polarity zygote. The zygote divides with an oblique-vertical cell plate facing the apical notch of the gametophyte.

关键词： EMBRYOLOGY FERNS CERATOPTERIS thalictroides MALE reproductive organs CHROMATIN FLAGELLA (Microbiology) PLANT reproduction

Formation of the Fertilization Pore during Oogenesis of the Fern Ceratopteris thalictroides

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Journal of Integrative Plant Biology 2010年第6期52卷 518-527页

作者： jian-guo cao quan-xi wang Wen-Mei Bao College of Life and Environment Sciences Shanghai Normal University Shanghai 200234 China

The development of the fertilization pore during oogenesis of the fern Ceratopteris thalictroides was followed using transmission electron microscopy. The newly formed egg is appressed closely to the adjacent cells. There are well-developed plasmodesmata between the egg and the ventral canal cell, but none between the egg and the jacket cells of the archegonium. During maturation, a separation cavity is formed around the egg. However, a pore region persistently connects the egg and the ventral canal cell. The extra egg membrane is formed by deposition of sheets of endoplasmic reticulum （ER）, but no ER is deposited on the inner surface of the pore region. Thus, a fertilization pore, covered by a layer of plasmalemma, is formed. The ventral canal cell undoubtedly participates the formation of the fertilization pore, probably by absorbing the sheets of ER beneath the pore region. The functional significance of the ventral canal cell in formation of the fertilization pore is discussed. The features of the mature egg include that abundant concentric membranes and osmiophilic vesicles occur in the cytoplasm of the mature egg. The initial, round nucleus of the egg eventually becomes cup-shaped. This investigation gives some new insights about the cells participating oogenesis in ferns.

关键词： FERTILIZATION of plants OOGENESIS CERATOPTERIS thalictroides TRANSMISSION electron microscopy PLASMODESMATA ENDOPLASMIC reticulum CELL membranes CELL interaction (Biology)

Characterization and Wettability of ZnO Film Prepared by Chemical Etching Method

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Chemical Research in Chinese Universities 2013年第2期29卷 333-337页

作者： guo Hua-xi JIA Hui-ying ZENG jian-bo CONG Qian REN Lu-quan Key Laboratory of Bionic Engineering Ministry of Education Jilin University Changchun 130025 P. R. China

ZnO thin films were prepared by a chemical etching method and their wettability was investigated. The structure and surface composition structure were characterized by means of scanning electron microscopy, X-ray photoelectronic spectrometry（XPS）, X-ray diffraction（XRD） and Raman spectrometry. These analyses reveal that the etched films were large-scale micro-nanohierarchical structures composed of a Zn core and a ZnO coating. Superhy- drophobic surfaces with water contact angles of over 150~ were obtained by n-octadecanethiol（ODT） modification. The XPS and Raman results indicate that ODT molecules were bound to the ZnO surface with the S head group by forming Zn--S bond.

关键词： ZnO Chemical etching Micro-nanostructure Raman spectrometry Wettability

Review on recent advances of inorganic electrode materials for potassium-ion batteries

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Tungsten 2024年第1期6卷 174-195页

作者： jian-Zhen xiong Ze-Cheng yang xin-Liang guo xi-ying wang Chao Geng Zong-Fu Sun An-Yong xiao quan-Chao Zhuang Ya-xin Chen Zhi-Cheng Ju School of Materials Science and Physics China University of Mining and TechnologyXuzhou 221116China

Rechargeable potassium-ion batteries(PIBs)have great potential in the application of electrochemical energy storage devices due to the low cost,the abundant resources and the low standard reduction potential of *** electrode materials are the key factors to determine the electrochemical performance of devices,relevant research is being carried out to build high-performance *** recent years,significant progress has been made in the study of the design of inorganic electrode ***,we review the cathode materials(Prussian blue and its analogues,layered oxides and poly anionic compounds)and the anode materials(antimony-based,selenium-based and bismuth-based compounds).On the basis of previous work,the structural design principles for improving the performance of electrode materials are reasonably *** the same time,the problems that need to be solved in the preparation of electrode materials and the direction of future research and improvement are pointed out.

关键词： Inorganic electrode materials Potassium-ion batteries Cathode materials Anode materials

In-situ observation of microstructural evolution in reheated low carbon bainite weld metals with various Ni contents

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Journal of Iron and Steel Research International 2017年第12期24卷 1206-1214页

作者： Gao-jun Mao Rui cao jian-hong Chen xi-li guo Yong jiang Department of Materials Science and Engineering Lanzhou University of TechnologyLanzhou 730050GansuChina State Key Laboratory of Advanced Processing and Recycling of Non ferrous Metals Lanzhou University of TechnologyLanzbou 730050GansuChina Atlantic China Welding Concumables Inc.Zigong 643000SichuanChina

Microstructural evolution in weld metals was in-situ observed through utilizing a laser scanning confocal microscope at two cooling *** specimens with various nickel contents were adopted for the *** the specimen with low fraction of Ni（≤2 wt.%）,granular bainite microstructure（*** surface relief）transformation from intragranular nucleation site was in-situ observed,while,lath bainite microstructure originating from grain boundary of austenite was in-situ observed for specimens with high mass percentage of Ni（≥4 wt.%）.With increasing nickel content,the transformation temperature *** prior austenite grain size was initially depressed and subsequently coarsened dramatically with the addition of *** microstructure difference was ascribed to various nucleation sites and growth direction in the *** account of those observations,not only the chemical component,cooling rate and microstructure were systematically correlated,but also the microstructural evolution was definite.

关键词： Weld metal Ni content Bainite Nucleation site Growth In-situ observation

Short term effects of small incision lenticule extraction surgery on corneal endothelium

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International Journal of Ophthalmology(English edition) 2016年第4期9卷 536-539页

作者： Dan-yang wang Man-Li Liu Yi-Le Chen xiao-ying Zhang yang-Tao Xu jian-Chao wang Chi-Ho To jian-guo wang quan Liu State Key Laboratory of Ophthalmology Zhongshan Ophthalmic CenterSun Yat-sen UniversityGuangzhou 510060Guangdong ProvinceChina Department of Ophthalmology Liuzhou Worker's HospitalLiuzhou 545006Guangxi Zhuang Autonomous RegionChina Department of Ophthalmology the Second Affiliated Hospital of Xi'an Jiaotong UniversityXi'an 710000Shaanxi ProvinceChina Laboratory of Experimental Optometry Centre for Myopia ResearchSchool of Optometrythe Hong Kong PolytechnicUniversityHong KongChina Wuzhishan Ophthalmic Hospital Wuzhishan 572200Hainan ProvinceChina Hainan Eye Hospital Zhongshan Ophthamic CenterSun Yat-sen UniversityHaikou 570311Hainan ProvinceChina

AIM： To assess the effects of small incision lenticule extraction（SMILE） surgery on the corneal endothelium at1 d to 1mo postoperatively.·METHODS： A retrospective, observational study was conducted on 47 patients（47 eyes） who received SMILE surgery. Patients were grouped according to contact lens wear condition. The corneal endothelium was examined preoperatively and at 1d, 1wk and 1mo *** corneal endothelium was analyzed for endothelial cell density（ECD）, percentage of hexagonal cells, and coefficient of variation（CV） of cell size.·RESULTS： There were no significant decrease in the ECD, percentage of hexagonal cells or increase in CV at1 d, 1wk and 1mo postoperatively（P 〉0.05）. However,there was a small increase of ECD by 2.88% in contact lens wearers（78.26±113.62 cell/mm2, P 〈0.05）.· CONCLUSION： SMILE has no significant adverse effects on the corneal ECD and morphology during 1mo follow-up time.

关键词： myopia corneal endothelium refractive surgery

8-bromo-7-methoxychrysin inhibits properties of liver cancer stem cells via downregulation of β-catenin

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World Journal of Gastroenterology 2013年第43期19卷 7680-7695页

作者： Mei-Fang quan Li-Hong xiao Zhi-Hong Liu Hui guo Kai-Qun Ren Fei Liu jian-guo cao xi-Yun Deng Medical College Hunan Normal University Department of pathology Hunan Provincial Tumor Hospital

AIM:To evaluate whether 8-bromo-7-methoxychrysin(BrMC),a synthetic analogue of chrysin,inhibits the properties of cancer stem cells derived from the human liver cancer MHCC97 cell line and to determine the potential ***:CD133+cells were sorted from the MHCC97 cell line by magnetic activated cell sorting,and amplified in stem cell-conditioned medium to obtain the enriched CD133+sphere forming cells(SFCs).The stem cell properties of CD133+SFCs were validated by the tumorsphere formation assay in vitro and the xenograft nude mouse model in vivo,and termed liver cancer stem cells(LCSCs).The effects of BrMC on LCSCs in vitro were evaluated by MTT assay,tumorsphere formation assay and transwell chamber *** effects of BrMC on LCSCs in vivo were determined using a primary and secondary xenograft model in Balb/c-nu *** of the stem cell markers,epithelialmesenchymal transition(EMT)markers andβ-catenin protein were analyzed by western blotting or immunohistochemical ***:CD133+SFCs exhibited stem-like cell properties of tumorsphere formation and tumorigenesis capacity in contrast to the parental MHCC97 *** found that BrMC preferentially inhibited proliferation and self-renewal of LCSCs(P<0.05).Furthermore,BrMC significantly suppressed EMT and invasion of ***,BrMC could efficaciously eliminate LCSCs in ***,we showed that BrMC decreased the expression ofβ-catenin in *** ofβ-catenin by small interfering RNA could synergize the inhibition of self-renewal of LCSCs induced by BrMC,while Wnt3a treatment antagonized the inhibitory effects of ***:BrMC can inhibit the functions and characteristics of LCSCs derived from the liver cancer MHCC97 cell line through downregulation ofβ-catenin expression.

关键词： Liver cancer Cancer stem cell 8-bromo7-methoxychrysin Self-renewal β-catenin

Laparoscopic partial splenectomy in the treatment of splenic ectopic pregnancy

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Hepatobiliary Surgery and Nutrition 2024年第3期13卷 569-572页

作者： Ke-xi Liao Li cao Yan-Zhou wang Bao-Lin wang Shu-guo Zheng jian-Wei Li Institute of Hepatobiliary Surgery First Affiliated HospitalArmy Medical UniversityChongqingChina Department of Gynecology and Obstetrics First Affiliated HospitalArmy Medical UniversityChongqingChina

Ectopic pregnancy is a pregnancy that occurred outside the uterus,usually in the fallopian tube,followed by other abdominal *** pregnancy could not develop normally to term and requires sufficient evaluation and intervention with medication or surgery in most cases(1).As a rare form of abdominal pregnancy(2),splenic ectopic pregnancy could be treated by drug treatment(3)or surgical interventions,including laparotomy and laparoscopy,which focused on total splenectomy(4,5).A previous study(6)indicated that laparoscopic partial splenectomy for selected patients was safe and *** to the fragile texture of the spleen,the suture method during laparoscopic partial splenectomy was technically demanding since it might encounter higher risk of splenic vascular hemorrhage than total ***,few reports focused on the treatment of splenic ectopic pregnancy via laparoscopic partial splenectomy(7).In order to avoid the potential severe complications such as hemoperitoneum(8)caused by drug treatment alone,and to avert impaired hematopoietic and immune function caused by total splenectomy,we herein presented a case(Video 1)of a 30-year-old woman(gravida 2,para 1)undergoing laparoscopic partial splenectomy performed by hepatobiliary surgeons to treat splenic ectopic pregnancy.

关键词： pregnancy splenectomy impaired

Frequency Measurement of the Electric Quadrupole Transition in a Single Laser-Cooled 40Ca＋

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Chinese Physics Letters 2011年第1期28卷 74-77页

作者： LIU Qu HUANG Yao cao jian OU Bao-quan guo Bin GUAN Hua HUANG Xue-Ren GAO Ke-Lin State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and Mathematics (WIPM) Chinese Academy of Sciences Wuhan 430071 Centers for Cold Atom Physics Chinese Academy of Sciences Wuhan 430071 Graduate School of the Chinese Academy of Sciences Beijing 100049 Department of Physics Science College National University of Defense Technology Changsha 410073

The optical frequency of the 4s2S1/2 3d2 Ds/2 transition in a single trapped and laser-cooled 40 Ca＋ ion is measured with an optical frequency comb system referenced to a hydrogen maser, A 729-nm laser can be locked ... 详细信息

关键词： Lasers Measurement