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Cytological analysis and genetic control of rice anther development

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Journal of Genetics and Genomics 2011年第9期38卷 379-390页

作者： Dabing Zhang xue luo Lu Zhu Institute of Plant Science State Key Laboratory of Hybrid Rice School of Life Sciences and Biotechnology Shanghai Jiao Tong University Shanghai 200240 China Bio-X Research Center Shanghai Jiao Tong University Shanghai 200240 China

Microsporogenesis and male gametogenesis are essential for the alternating life cycle of flowering plants between diploid sporophyte and haploid gametophyte generations. Rice （Oryza sativa） is the world＇s major staple food, and manipulation of pollen fertility is particularly important for the demands to increase rice grain yield. Towards a better understanding of the mechanisms controlling rice male reproductive development, we describe here the cytological changes of anther development through 14 stages, including cell division, differentiation and degeneration of somatic tissues consisting of four concentric cell layers surrounding and supporting reproductive cells as they form mature pollen grains through meiosis and mitosis. Furthermore, we compare the morphological difference of anthers and pollen grains in both monocot rice and eudicot Arabidopsis thaliana. Additionally, we describe the key genes identified to date critical for rice anther development and pollen formation.

关键词： Rice (Oryza Sativa) Anther Developmental stages Cellular morphology Arabidopsis thaliana

OPTIMAL CONTROL FOR A NONLINEAR n-DIMENSIONAL COMPETING SYSTEM WITH AGE-STRUCTURE

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International Journal of Biomathematics 2012年第3期5卷 133-144页

作者： ZHI-xue luo JIAN-YU YANG YA-JUAN luo Department of Mathematics Lanzhou Jiaotong University Lanzhou 730070 P. R. China Department of AuditLanzhou Jiaotong UniversityLanzhou 730070 P. R. China School of Automation & Electrical Engineering Lanzhou Jiaotong University Lanzhou 730070 P. R. China

This paper is concerned with optimal harvesting control of a first order partial differential equation system representing a nonlinear n-dimensional competitive population model with age-structure. By the Ekeland＇s variational principle, the existence and unique char- acterization of the optimal control strategy are established. The optimality conditions for the control problem are obtained by the concept of the normal cone.

关键词： Optimal control age-dependence competition the maximum principle.

PERSISTENCE, EXTINCTION AND STABILITY FOR NONLINEAR PLANKTON ALLELOPATHY MODEL WITH DELAYED NEGATIVE FEEDBACKS

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International Journal of Biomathematics 2012年第2期5卷 157-196页

作者： YAN-PING LIU ZHI-xue luo College of Science Gansu Agricultural University Lanzhou 730070P.R.China Department of Mathematics Lanzhou Jiaotong University Lanzhou 730070P.R.China

By the techniques of comparison argument and Lyapunov-like functionals, some criteria about persistence and extinction of the species are obtained. And then, with the help of constructing Lyapunov functionals and some new analysis method, sufficient conditions, provided with the form of average value of a function, to guarantee the stability of the system are derived. Finally, some examples together with their numerical simulations show the feasibility of these main results. Our conclusions are different from many existing forms for nonlinear competitive systems.

关键词： Persistence extinction stability toxicant Lyapunov functional delay.

Gastrointestinal bleeding caused by extrahepatic arterioportal fistula associated with portal vein thrombosis

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World Journal of Gastroenterology 2012年第44期18卷 6501-6503页

作者： Ling Nie xue-Feng luo Xiao Li Laboratory of Pathology Department of Pathology State Key Laboratoty of Biotherapy West China Hospital Sich- uan University Chengdu 610041 Sichuan Province China Department of Gastroenterology West China Hospital Sichuan University Chengdu 610041 Sichuan Province China Center for Vascular and Liver Disease West China Hospital Sichuan University Chengdu 610041 Si- chuan Province China

An extrahepatic arterioportal fistula(APF) involving the gastroduodenal artery and superior mesenteric vein is rare and mostly results from iatrogenic *** clinical symptoms associated with APFs may include abdominal pain,gastrointestinal bleeding,ascites,nausea,vomiting,diarrhea,or even congestive heart *** present the case of a 70-year-old man who presented with chronic abdominal pain and gastrointestinal bleeding secondary to APF and portal vein *** endovascular embolization of APF was accomplished successfully,and symptoms of portal hypertension resolved immediately after ***,the patient did not respond well to anticoagulation therapy with ***,the patient underwent implantation of a transjugular intrahepatic portosystemic shunt,and the complications of portal hypertension *** conclusion,the embolization of APF is technically feasible and effective and can be considered the first-choice therapy in selected patients.

关键词： Extrahepatic arterioportal fistula Portal veinthrombosis Embolization Transjugular intrahepaticportosystemic shunt

Distribution of platelet-derived growth factor-alpha receptor expressing oligodendrocyte precursor cells in the adult rat brain

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Neural Regeneration Research 2009年第12期4卷 1093-1098页

作者： Hongjun Yu Jun Fei xue luo Zhongxiang Yao Department of Rehabilitation Southwest Hospital Third Military Medical University Chongqing 400038 China Department of Histology and Embryology Third Military Medical University Chongqing 400038 China Trauma Center of Daping Hospital Third Military Medical University Chongqing 400038 China

BACKGROUND： Studies have demonstrated that NG2-positive glial cells in the adult rats are predominantly located in the gray and white matter of the cerebral cortex and hippocampus. Platelet-derived growth factor-a receptor （PDGF-αR） cells are a subset of oligodendrocytes, which are not as mature as NG2-positive cells. Distribution and migration of PDGF-αR-positive cells in the rat brain remain poorly understood. OBJECTIVE： Using immunohistochemical methods, the distribution of oligodendrocyte precursor cells （PDGF-αR-positive） was analyzed in the adult rat brain. DESIGN, TIME AND SETTING： Immunohistochemical study was performed at the Department of Histology and Embryology of the Third Military Medical University from September 2007 to September 2008. MATERIALS： Rabbit anti-PDGF-αR polyclonal antibody was purchased from Santa Cruz Biotechnology, USA. Streptomycin-avidin-biotin complex immunohistochemistry kit was purchased from Zhongshan Goldenbridge Biotechnology, China. METHODS： Whole brains from 5 healthy, adult, Wistar rats were collected for immunohistochemistry, and the mean value of PDGF-αR-expressing cells was quantified. The absolute values were translated to ranked data of high, moderate, and low grades （high grade： 10 positive cells; moderate grade： 5-9 cells; low grade：〈 5 cells in a 400 × visual field）. Based on the number of cell processes and branches, as well as the number of PDGF-αR-positive cells, in different regions, the cells were classified into three categories, i.e., type Ⅰ-Ⅲ. From type I to type Ill, the number of processes gradually increased. MAIN OUTCOME MEARSURES： The number and distribution of PDGF-αR-positive cells in different brain regions of adult rats. RESULTS： PDGF-αR-positive cells were located in the forebrain and midbrain, but not in the cerebellum or brainstem. In the olfactory bulb and hippocampus, a total of 60% PDGF-αR-positive cells were type Ⅰ and these cells were not mature as others. In the cerebral cortex, olfactory s

关键词： Platelet-derived growth factor-α receptor oligodendrocyte progenitor cells brain distribution

Study on semantic-oriented hybrid indexing strategy of resource metadata in peer-to-peer network

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第1期8卷 88-94页

作者： LIU Zhen ZHOU Mao-wei HUANG Hong-bin luo xue-shan College of Information System and Management National University of Defense Technology Changsha 410073 China

Applying ontology to describe resource metadata richly in the peer-to-peer environment has become current research trend. In this semantic peer-to-peer environment, indexing semantic element of resource description to support efficient resource location is a difficult and challenging problem. This paper provided a hybrid indexing architecture, which combines local indexing and global indexing. It uses community strategy and semantic routing strategy to organize key layer metadata element and uses DHT (distributed hash table) to index extensional layer metadata element. Compared with related system, this approach is more efficient in resource location and more scalable.

关键词： Peer-to-peer (P2P) Ontology Metadata Resource indexing

Evaluation of Tensile and Fatigue Properties of Metals Using Small Specimens

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Acta Metallurgica Sinica(English Letters) 2023年第1期36卷 147-157页

作者： Wen‑Ke Yang Zhu‑Man Song xue‑Mei luo Guang‑Ping Zhang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China

Small specimens are increasingly being used in getting mechanical properties directly when there are limited materials to facilitate standard specimens,which play a great role in the rapid measurement of mechanical properties and residual life assessment of in-service reactor *** tensile and fatigue properties of the small specimens are investigated extensively,theoretical models for describing the mechanical properties of small specimens need to be ***,we conduct a systematic investigation of tensile and fatigue properties of pure Cu specimens with thicknesses ranging from 3 to 0.2 *** results show that the decrease in uniform elongation of the 0.2 mm-thick specimens is mainly due to the efects of grain boundary and free surface on the strain hardening rate.A modifed theoretical model correlated with the ratio of the surface grain layer thickness to the grain size is proposed to predict variation in yield strength of the small specimens more ***,the mechanism for the diference in fatigue life between the 0.2 mm-thick specimen and other thicker specimens is *** Basquin equation-based model is presented as a potential way to evaluate the fatigue life of metals using small specimens.

关键词： Size efect Small specimen Tensile property Fatigue life

Expression and localization of inwardly rectifying potassium channel Kit2.1 in glia cells of native bovine retina

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Journal of Central South University of Technology 2005年第Z1期12卷 350-355页

作者： PAN Ai-hua luo xue-gang Department of Anatomy and Neurobiology Xiangya School of Medicine Central South University Changsha 410013 China Department of Anatomy and Neurobiology Xiangya School of Medicine Central South University Changsha 410013 China

Objective The purpose of this study is to identify the molecular basis of the contacting -neuron membrane K+ conductance in glia cells of native bovine retina. Methods RT-PCR, Northern blot and Western blot analyses were used to detect the expression of the inwardly rectifying K+ (Kir) channel subunits Kir2.1 in native bovine RPE and neural retina. The distribution of Kir2.1 protein was determined in frozen sections of bovine retina-RPEchoroid by indirect immunofluorescence analysis. Results RT-PCR analysis reveals Kir2.1 transcript in both RPE and neural retina. In Northern blots, Kir2.1 probe hybridizes to an appropriately sized-transcript in neural retina but not in RPE. In Western blots, Kir2.1 antibody recognizes a major monomer of about 60 kDa in neural retina but not in RPE. Immunofluorescence reveals that Kir2.1 immunostaining is expressed at many parts of Muller cells, especially in the membrane domains of Muller cells that contact retinal neurons, i. e. , along the two stem processes,over the soma, and in the side branches extending into the synaptic layers. No immunostaining is seen in RPE. Doubling staining shows that Kir2.1 proteins and glutamine synthetase proteins which are a marker of Muller cell co-localized well. Conclusions These results reveal that Kir2.1 is localized in the Muller cells, no Kir2.1 in RPE. These data suggests that Kir2.1 may be involved in the transport of K+ in the bovine neural retina.

关键词： Kir2.1 Muller cell glia cell retina

Endoscopic magnetic compression stricturoplasty for congenital esophageal stenosis:A case report

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World Journal of Clinical Cases 2022年第33期10卷 12313-12318页

作者： Shi-Qi Liu Yi Lv Rui-xue luo Department of Nursing The Medical CollegeXijing UniversityXi’an 710123Shaanxi ProvinceChina Department of Hepatobiliary Surgery The First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina The Corrosion&Protection Research Lab Northwest Institute for Nonferrous Metal ResearchXi’an 710016Shaanxi ProvinceChina

BACKGROUND Congenital esophageal stenosis(CES)is a rare malformation of the digestive *** dilation and thoracotomy have been the main treatments for ***,there is no well-defined management *** compression stricturoplasty(MCS)has been used in refractory esophageal stricture in children after esophageal *** SUMMARY We describe the first case of MCS for CES in one female child *** child(aged 3 years and 1 mo)was admitted due to frequent vomiting and choking after eating complementary food since 7 mo *** and gastroendoscopy showed that there was stenosis in the lower esophagus,suggesting a diagnosis of *** patient did not receive any treatment for esophageal stricture including surgery or endoscopic dilation procedures before *** procedure was smoothly conducted without *** 24 mo after MCS,durable esophageal patency without dysphagia was *** MCS may serve as an alternative and efficient method for patients with CES.

关键词： Congenital esophageal stenosis Magnetic compression stricturoplasty Endoscopy Case report