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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

Ultrastructure of the Mature Egg and Fertilization in the Fern Ceratopteris thalictroides

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Journal of Integrative Plant Biology 2009年第3期51卷 243-250页

作者： jian-guo cao Nai-Ying Yang quan-xi wang College of Life and Environment Sciences Shanghai Normal University Shanghai 200234 China

The ultrastructure of the mature egg and fertilization in the fern Ceratopteris thafictroides （L.） Brongn. were observed by transmission electron microscopy. The results revealed that the mature egg possesses an obvious egg membrane at the periphery of the egg. Furthermore, a fertilization pore was identified in the upper egg membrane of the mature egg. The structure of the pore is described for the first time. The fertilization experiment indicated that spermatozoids crowd into the cavity above the egg through the neck canal of the archegonium; however, only one of these can penetrate into the egg through the fertilization pore. Immediately on penetration of the spermatozoid, the egg begins to shrink. The volume of the fertilized egg decreases to almost one-half that of the unfertilized egg. As a result, the protoplasm of the fertilized egg becomes dense and opaque, which may lead to a situation where the organelles of both the egg and the fertilizing spermatozoid become indistinguishable. Simultaneously, abundant vesicles containing concentric membranes or opaque materials appear near the fertilization pore in the cytoplasm of the fertilized egg. These vesicles are considered to act as a barrier that prevents polyspermy. The present study provides a new insight into the ultrastructure of the mature egg and the cytological mechanism of fertilization in ferns.

关键词： Ceratopteris thalictroides fern fertilization fertilization pore.

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

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三种毛枝藻的培养研究及其异丝性特征

植物分类学报 2006年第6期44卷 654-669页

作者：祖国辉包文美王全喜曹建国哈尔滨师范大学生命与环境科学学院哈尔滨150080 上海师范大学生命与环境科学学院上海200234

毛枝藻属Stigeoclonium植物是异丝性藻类,由直立系统和匍匐系统共同组成;直立系统的形态高度变化,虽然匍匐系统的形态比直立系统的形态稳定,但野外采来的标本匍匐系统不全,影响鉴定的效果。将采自野外的10号毛枝藻属样的标本通过实验室... 详细信息

毛枝藻属Stigeoclonium植物是异丝性藻类,由直立系统和匍匐系统共同组成;直立系统的形态高度变化,虽然匍匐系统的形态比直立系统的形态稳定,但野外采来的标本匍匐系统不全,影响鉴定的效果。将采自野外的10号毛枝藻属样的标本通过实验室培养,观察到它们从孢子萌发至匍匐系统和直立系统发育全过程的细节,确定其中3种毛枝藻的种名为夏毛枝藻***(Haz.)Coll.、偏生毛枝藻***ütz.和丰满毛枝藻***。夏毛枝藻和偏生毛枝藻孢子萌发大致为匍匐式,夏毛枝藻匍匐系统是分枝的丝状体,不产生假根,细胞圆球形或短圆柱形,内具叶绿体;偏生毛枝藻的匍匐系统是假二叉分枝的假根,假根由单列长圆柱形细胞组成,最后叶绿体消失变为无色;丰满毛枝藻的孢子萌发是严格的匍匐式,匍匐系统由主枝和分枝构成假薄壁组织的盘状结构。这3种毛枝藻的匍匐系统都各具其独特而持久的形态特征。它们的直立系统都是分枝的丝状体,夏毛枝藻和偏生毛枝藻分枝较多,一侧生或互生,无对生,枝顶尖细或为毛状,前者细胞宽7–9μm,长17–30μm,长为宽的3–4倍;后者宽10–14μm,长18–36μm,长为宽的2–3倍,细胞外胶质层厚。丰满毛枝藻分枝稀少或不发育,细胞宽8–10μm,长9–32μm,长为宽的2–4倍。但此3种毛枝藻直立系统的形态特点是不稳定而可变的,故毛枝藻的分类应主要参考它们的匍匐系统而定。首次报道了中国产毛枝藻的培养研究。

关键词：毛枝藻属夏毛枝藻偏生毛枝藻丰满毛枝藻藻类分类藻类培养异丝性藻类

中国羽纹藻属(硅藻门)的新记录植物(英文)

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植物分类学报 2007年第3期45卷 346-352页

作者：刘妍王全喜曹建国上海师范大学生命与环境科学学院上海200234

报道了采自大兴安岭达尔滨湖及其周围沼泽水体的硅藻门Bacillariophyta羽纹藻属Pinnularia中国新记录植物5种3变种,分别为北方羽纹藻近岛变种*** *** Krammer、极歧纹羽纹藻近喙头变种*** *** Cleve-Euler、巨大羽纹藻*** Cleve、不定... 详细信息

报道了采自大兴安岭达尔滨湖及其周围沼泽水体的硅藻门Bacillariophyta羽纹藻属Pinnularia中国新记录植物5种3变种,分别为北方羽纹藻近岛变种*** *** Krammer、极歧纹羽纹藻近喙头变种*** *** Cleve-Euler、巨大羽纹藻*** Cleve、不定羽纹藻*** Krammer、狗鱼形羽纹藻*** Fusey、斯匹次羽纹藻*** Cleve、波曲羽纹藻*** (Schumann) Krammer和波曲羽纹藻中狭变种*** *** Krammer。对这些种类在光镜和扫描电镜下的分类学特征进行了详细的描述,并记录了这些种的生境特点。

关键词：羽纹藻属新记录中国

Stepped-up development of accelerator mass spectrometry method for the detection of ^(60)Fe with the HI-13 tandem accelerator

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Nuclear Science and Techniques 2024年第4期35卷 136-143页

作者： Yang Zhang Sheng-quan Yan Ming He Qing-Zhang Zhao wen-Hui Zhang Chao-xin Kan jian-Ming Zhou Kang-Ning Li xiao-Fei wang jian-Cheng Liu Zhao-Hua Peng Zhuo Liang Ai-Ling Li jian Zheng Qi-wen Fan Yun-Ju Li You-bao wang Zhi-Hong Li Yang-Ping Shen Ding Nan Wei Nan Yu-Qiang Zhang Jia-Ying-Hao Li Jun-wen Tian jiang-Lin Hou Chang-xin guo Zhi-Cheng Zhang Ming-Hao Zhu Yu-wen Chen Yu-Chen jiang Tao Tian Jin-Long Ma Yi-Hui Liu Jing-Yu Dong Run-Long Liu mei-Yue-Nan Ma Yong-Shou Chen Wei-Ping Liu Bing guo China Institute of Atomic Energy P.O.Box 275(10)Beijing 102413China College of Science Southern University of Science and TechnologyShenzhen 518055China School of Physics Xi’an Jiaotong UniversityXi’an 710049China

The Moon provides a unique environment for investigating nearby astrophysical events such as *** samples retain valuable information from these events,via detectable long-lived“fingerprint”radionuclides such as^(60)*** this work,we stepped up the development of an accelerator mass spectrometry(AMS)method for detecting^(60)Fe using the HI-13tandem accelerator at the China Institute of Atomic Energy(CIAE).Since interferences could not be sufficiently removed solely with the existing magnetic systems of the tandem accelerator and the following Q3D magnetic spectrograph,a Wien filter with a maximum voltage of±60 kV and a maximum magnetic field of 0.3 T was installed after the accelerator magnetic systems to lower the detection background for the low abundance nuclide^(60)Fe.A 1μm thick Si_(3)N_(4) foil was installed in front of the Q3D as an energy *** particle detection,a multi-anode gas ionization chamber was mounted at the center of the focal plane of the ***,an^(60)Fe sample with an abundance of 1.125×10^(-10)was used to test the new AMS *** results indicate that^(60)Fe can be clearly distinguished from the isobar^(60)*** sensitivity was assessed to be better than 4.3×10^(-14)based on blank sample measurements lasting 5.8 h,and the sensitivity could,in principle,be expected to be approximately 2.5×10^(-15)when the data were accumulated for 100 h,which is feasible for future lunar sample measurements because the main contaminants were sufficiently separated.

关键词： Accelerator mass spectrometry Wien filter Isobar separation Supernovae Chang'e-5 lunar samples

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两种胶毛藻科植物的培养研究

西北植物学报 2008年第11期28卷 2217-2225页

作者：曹建国祖国辉包文美王全喜上海师范大学生命与环境科学学院上海200234 哈尔滨师范大学生命与环境科学学院哈尔滨150080

对胶毛藻科植物优美胶毛藻[Chaetophora elegans（Roth）Agardh]和羽枝竹枝藻[Draparnaldia plumosa（Vauch） Agardh]进行了室内培养,对它们自游动孢子萌发到成熟丝状体形成等生活史各阶段都进行了详细观察,并做了活体显微镜照相记录... 详细信息

对胶毛藻科植物优美胶毛藻[Chaetophora elegans（Roth）Agardh]和羽枝竹枝藻[Draparnaldia plumosa（Vauch） Agardh]进行了室内培养,对它们自游动孢子萌发到成熟丝状体形成等生活史各阶段都进行了详细观察,并做了活体显微镜照相记录。结果显示：（1）优美胶毛藻的游动孢子较小,直径为9--11μm,顶端具4条等长鞭毛,自母细胞释放后,游动孢子固定在基质上萌发,萌发类型为直立式,顶端细胞发育为直立系统,其直立系统为二叉状分枝,无明显主枝,侧枝发达,分枝顶端细胞渐尖或毛状,各级分枝细胞大小基本相同,圆柱形,宽约为6--8μm,长约为10--12μm。基细胞发育为匍匐系统,首先产生匍匐枝,由它产生假根。随生长,直立系统下部的细胞产生次生假根,成熟的优美胶毛藻外观近球形,与野生胶毛藻的形态相似。（2）羽枝竹枝藻游动孢子产生于母细胞,游动孢子体积较大,直径约为30μm左右,顶端具4条等长鞭毛。游动孢子从母细胞内释放后,固定在基质上萌发,萌发类型亦为直立式,顶端细胞发育为直立系统,其直立系统为分枝丝状体,主枝粗壮,细胞圆柱形,长约为50--60μm,宽约为48--50μm,内有多个蛋白核;侧枝细胞为长圆形,长约为40--50μm,宽约为17--19μm,分枝顶端的细胞尖细或为毛状。基细胞发育为假根和匍匐枝。当藻体成熟时,直立系统下部的细胞产生次生假根。

关键词：胶毛藻科羽枝竹枝藻优美胶毛藻藻类培养

Novel thick-target inverse kinematics method for the astrophysical ^(12)C+^(12)C fusion reaction

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Nuclear Science and Techniques 2024年第11期35卷 237-243页

作者： Wei-Ke Nan You-bao wang Yao-De Sheng Jun Su Yu-Qiang Zhang Lu-Yang Song Yang-Ping Shen Fu-Qiang cao Chen Chen Chao Dong Yun-Ju Li Zhi-Hong Li Gang Lian Wei Nan Qiang wang Na Song Sheng-quan Yan Seng Zeng Qi-wen Fan Hao Zhang Ming-Hao Zhu Bing guo Wei-Ping Liu China Institute of Atomic Energy P.O.Box 275(10)Beijing 102413China Key Laboratory of Beam Technology and Material Modification of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China School of Physics Xi’an Jiaotong UniversityXi’an 710049China Department of Physics Southern University of Science and TechnologyShenzhen 518055China

The ^(12)C+^(12)C fusion is one of the most important reactions in modern nuclear *** trend and magnitude of the reaction rate within the Gamow window strongly influence various astrophysical ***,direct measurement of this reaction is extremely difficult,which makes it necessary to develop indirect *** this study,the ^(23)Na+p reaction system was used to study the compound nucleus ^(24)*** employed a thick-target inverse kinematics method combined with theγ-charged-particle coincidence technique to measure the proton andα exit channels of ^(24)*** details of the ^(23)Na+p thick-target inverse kinematics experiment and analysis are presented herein.

关键词： Nuclear astrophysics ^(12)C+^(12)C Thick-target inverse kinematics method γ-charged particle coincidence

绵马鳞毛蕨精母细胞和游动精子超微结构特征的研究(英文)

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西北植物学报 2005年第4期25卷 761-769页

作者：曹建国何群王全喜田国伟包文美上海师范大学生命与环境科学学院哈尔滨学院生物系哈尔滨师范大学生命与环境科学学院哈尔滨师范大学生命与环境科学学院哈尔滨150080

应用电镜技术对蕨类植物绵马鳞毛蕨DryopteriscrassirhizomaNakai精母细胞和游动精子的超微结构特征进行了研究.精母细胞为多边形,细胞质内含有丰富的线粒体、质体、内质网、高尔基体等常见的细胞器,在细胞质中还可见到一些同心圆膜状结... 详细信息

应用电镜技术对蕨类植物绵马鳞毛蕨DryopteriscrassirhizomaNakai精母细胞和游动精子的超微结构特征进行了研究.精母细胞为多边形,细胞质内含有丰富的线粒体、质体、内质网、高尔基体等常见的细胞器,在细胞质中还可见到一些同心圆膜状结构,位于质膜的附近或精母细胞的角偶.同心圆膜状结构由双层膜环绕构成,外被1层单位膜.精母细胞与精子器的璧细胞之间形成了分离腔,在精母细胞质膜外形成了嗜锇层,这些结构的形成说明精母细胞已经开始与雄配子体逐渐分离,进入独立发育的阶段.尽管精母细胞之间也有嗜锇层的形成,但嗜锇层是不连续的,其上有一些空隙,精母细胞之间可通过空隙进行物质和信息的交流.成熟的精子细胞外被1层透明的薄膜,里面为游动精子,螺旋状,由环状细胞器环绕3～4圈构成,这些环状细胞器包括多层结构、微管带、巨大线粒体、鞭毛带和1个长形浓缩的细胞核.游动精子的后端为一些泡囊化的细胞质,其中包括一些残存的线粒体、造粉质体及大的囊泡等.当成熟的精子细胞排出精子器后,其内的游动精子挣脱透明质膜的束缚,摆脱后端的囊泡,成为1条游动精子.本文还对绵马鳞毛蕨和其它蕨类植物精子的超微结构特征进行了比较.

关键词：绵马鳞毛蕨精母细胞游动精子超微结构