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哺乳动物性别分化的调控 总被引:2,自引:0,他引:2
哺乳动物性别分化调控的分子机制的研究特别是性别分化的层次调控、剂量补偿和性染色体进化这三个领域,已取得快速进展。已经发现Y染色体性别决定区基因(SRY)、X染色体DSS-AHC决定区基因1(DAX-1)、甾类生成因子1基因(SF1)和Wilms瘤抑制基因(WT-1)等与哺乳动物性别决定有关。SRY启动睾丸分化,但胚胎发育成雄性的其余步骤由睾丸分泌的激素控制。DAX-1编码一种女性特异功能的蛋白质, 相似文献
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昆虫促前胸腺激素研究进展 总被引:4,自引:0,他引:4
昆虫促前胸腺激素研究进展李毅平龚和(中国科学院动物研究所,北京100080)关键词促前胸腺激素受体信号系统促前胸腺激素(prothoracicotropichor-monePTTH)因其促进前胸腺(PG)合成和分泌蜕皮激素而得名,以前也称为脑激素,因... 相似文献
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海洋微藻基因工程的选择标记 总被引:12,自引:0,他引:12
6种海洋微藻新月菱形藻(Nitzschia closterium Ehr.)、牟勒氏角刺藻(Chaetocdros muelleri Lemm.)、三角褐指灌(Phaeodactylum tricornutum Bohl.)绿光等鞭金藻8701(Isochrysis galbana Parke 8701)、亚心形扁藻(Platymonas subcordi-formis(Wille)Hazen)和 相似文献
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家蚕蜕皮与变态的内分泌调控 总被引:3,自引:1,他引:2
家蚕的蜕皮与变态是由前胸腺分泌的脱皮素(molting hormone或 ecdysteroid简称 MH)及由咽侧体分泌的保幼激素(juvenile hormone)控制的,而促有前胸腺激素(prothoracicotropic hormone,以下简称PTTH)的功能为刺激前胸腺分泌蜕皮素。笔者近10年来从家蚕内分泌体系的一系列研究中发现,蜕皮素浓度的变化可以通过控制咽侧体的保幼激素的生物合成来影响幼虫发育,而PTTH的信息传递可通过调控前胸腺的功能,进而影响血淋巴中蜕皮素浓度。 相似文献
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秦岭南坡旬河流域及邻近地区森林与其生境关系的初步研究 总被引:3,自引:0,他引:3
秦岭南坡旬河流域及邻近地区森林与其生境关系的初步研究康慕谊(西北大学地理系,西安710069)RelationshipbetweenForestVegetationandItsHabitatsinXunheRiverBasinofQinlingMountainandItsAdjacentAreas¥KangMuyi(DepartmentofGeography,NorthwestUniversity,Xiaan710069).ChineseJournalofEcology,1993,12(6):62-66.Principlesofvegetationecologyandmethodofmultivariateanalysis(DoubleSievingStepRegression)areappliedtorevealthegeneralrelationshipbetweenforestvegetationanditshabitatsintheupperandmid-dlereachesofXunheRiverbasinandtheiradjacentareas。Theresultsshowthatthespe 相似文献
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小兴安岭阔叶红松林凋落物产量及动态的研究 总被引:7,自引:0,他引:7
小兴安岭阔叶红松林凋落物产量及动态的研究刘传照,李景文,潘桂兰,李传荣(东北林业大学红松研究所,黑龙江带岭153106)LitterProductionandDynamicsinBroadleavcd-KoreanPineForestsinXiaoxinganMountaiils¥LiuChuanzhao;LiJingwen;PanGuilan;LiChuanrong(InstituteofKoreanPineStudies,NortbeastForestryUniversity,Dailing,Heilongjiang153106).ChneseJournalofEcology,1993,12(6):29-33.Three-yearstudywasdoneonlitterproductionanddynamicsunderbroadleaved-KoreanpineforestsintheXiaoxinganMountains。Resultsshowedthatannuallitterfallis4.25±0.17t.ha ̄(-1).yr ̄(-1).Amongtotallitterfall,leaflit 相似文献
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广东黑石顶常绿阔叶林生物量及其分配的研究 总被引:24,自引:0,他引:24
本文采用标准木和回归分析法(乔木层)及样方收获法(灌木层,草本层)研究了黑石顶自然保护区南亚热带常绿阔叶林的生物量及其分配规律。1.四种回归模型:(a)Y=a+bX,(b)Y=aX^b,(c)Y=ac^bx,(d)Y=a+blnX都能成功地应用于该森林的生物量研究,但一般以(b)及(c)的相关系数较高。对较大胸径的样木组(D≥10cm)直径方程的唯一显著的模型。2.森林总生物量为357.976t· 相似文献
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哺乳动物性别分化调控的分子机制的研究特别是性别分化的层次调控、剂量补偿和性染色体进化这三个领域,已取得快速进展。已经发现Y染色体性别决定区基因(SRY)、X染色体DSS-AHC决定区基因1(DAX-1)、甾类生成因子1基因(SF1)和Wilms瘤抑制基因(WT-1)等与哺乳动物性别决定有关。SRY启动睾丸分化,但胚胎发育成雄性的其余步骤由事丸分泌的激素控制。DAX-1且编码一种女性特异功能的蛋白质,它在男性中被SRY所抑制。SF-1和WT-1在SRY开启之前作用于性腺和肾上腺发育的启动。哺乳动物通过随机失活雌性两条X染色体中的一条来使X连锁的基因在两性间的表达水平达到平衡(剂量补偿)。X染色体失活由X染色体失活中心(XIC)控制。失活的X染色体专一转录基因(XIST)是XIC的强烈候选者,它可能参与X失活的启动。对有袋目和单孔目动物性染色体的研究为我们提供了其进化的信息。有证据支持性染色体起源于一对同源常染色体,而SRY的祖先基因可能是SOX-3。 相似文献
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Michael Hesse 《Plant Systematics and Evolution》1980,134(3-4):229-267
Some closely related members of the monocotyledonous familiesAlismataceae, Liliaceae, Juncaceae, Cyperaceae, Poaceae andAraceae with variable modes of pollination (insect- and wind-pollination) were studied in relation to the ultrastructure of pollenkitt and exine (amount, consistency and distribution of pollenkitt on the surface of pollen grains). The character syndromes of pollen cementing in entomophilous, anemophilous and intermediate (ambophilous or amphiphilous) monocotyledons are the same in principal as in dicotyledons. Comparing present with former results one can summarize: 1) The pollenkitt is always produced in the same manner by the anther tapetum in all angiosperm sub-classes. 2) The variable stickiness of entomophilous and anemophilous pollen always depends on the particular distribution and consistency of the pollenkitt, but not its amount on the pollen surface. 3) The mostly dry and powdery pollen of anemophilous plants always contains a variable amount of inactive pollenkitt in its exine cavities. 4) A step-by step change of the pollen cementing syndrome can be observed from entomophily towards anemophily. 5) From the omnipresence of pollenkitt in all wind-pollinated angiosperms studied one can conclude that the ancestors of anemophilous angiosperms probably have been zoophilous (i.e. entomophilous) throughout. 相似文献
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Surveillance of Class Ⅰ Newcastle Disease Virus at Live Bird Markets and Commercial Poultry Farms in Eastern China Reveals the Epidemic Characteristics 下载免费PDF全文
Xiaolong Lu Xiaoquan Wang Tiansong Zhan Yifan Sun Xin Wang Naiqing Xu Tianxing Liao Yu Chen Min Gu Shunlin Hu Xiaowen Liu Xiufan Liu 《中国病毒学》2021,36(4):818-822
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正Dear Editor,Parainfluenza virus 5 (PIV5), known as canine parainfluenza virus in the veterinary field, is a negative-sense,nonsegmented, single-stranded RNA virus belonging to the Paramyxoviridae family (Chen 2018). The virus was first reported in primary monkey kidney cells in 1954 (Hsiung1972), then it has been frequently discovered in various 相似文献
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Altaf Hussain Tiantian Wu Hui Li Linjin Fan Kai Li Li Gao Yongqiang Wang Yulong Gao Changjun Liu Hongyu Cui Qing Pan Yanping Zhang Asim Aslam Khan Muti-Ur-Rehman Muhammad Munir Salman Latif Butt Xiaomei Wang Xiaole Qi 《中国病毒学》2019,34(1):102-105
<正>Dear Editor,Infectious bursal disease (IBD) is one of the most important diseases of the poultry. The IBD virus (IBDV), a nonenveloped virus belonging to the Birnaviridae family with a genome consisting of two segments of double-stranded RNA (segments A and B), targets B lymphocytes of bursa of Fabricious leading to immunosuppression. In Pakistan,poultry farming is the second biggest industry and IBD is the second biggest disease threating the poultry sector.However, there is limited genome information of IBDV 相似文献
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Jiaming Li Yidun Zhang Lina Jiang Hongliang Cheng Jingjing Li Li Li Zehui Chen Fei Tang Yingying Fu Yifei Jin Bing Lu Jing Zheng Zhongyi Wang 《中国病毒学》2022,37(5):762-764
Highlights
1 Aerosol emission rates of Delta or Omicron patients were similar.
2 Viral loads in upper respiratory tract of Alpha, Delta and Omicron patients were similar.
3 Viral loads in upper respiratory tract of vaccinated or unvaccinated Delta patients had no difference. 相似文献
1 Aerosol emission rates of Delta or Omicron patients were similar.
2 Viral loads in upper respiratory tract of Alpha, Delta and Omicron patients were similar.
3 Viral loads in upper respiratory tract of vaccinated or unvaccinated Delta patients had no difference. 相似文献
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Danrong Shi Keda Chen Xiangyun Lu Linfang Cheng Tianhao Weng Fumin Liu Nanping Wu Lanjuan Li Hangping Yao 《中国病毒学》2022,37(2):295-298
Highlights
1) A comprehensive evaluation method for anti-SARS-CoV-2 drugs was established based on RT-qPCR, TCID50 method, and immunofluorescence.
2) A significant antiviral effect of rHuIFN-α1b was shown with EC50=0.12 IU/mL in Vero cells and EC50=0.52 IU/mL in Calu-3 cells, which was better than rHuIFN-α2b (EC50=0.25 IU/mL in Vero cells and EC50=2.48 IU/mL in Calu-3 cells).
3) rHuIFN-α1b has a good potential in the application of anti-COVID-19 therapy. 相似文献
1) A comprehensive evaluation method for anti-SARS-CoV-2 drugs was established based on RT-qPCR, TCID50 method, and immunofluorescence.
2) A significant antiviral effect of rHuIFN-α1b was shown with EC50=0.12 IU/mL in Vero cells and EC50=0.52 IU/mL in Calu-3 cells, which was better than rHuIFN-α2b (EC50=0.25 IU/mL in Vero cells and EC50=2.48 IU/mL in Calu-3 cells).
3) rHuIFN-α1b has a good potential in the application of anti-COVID-19 therapy. 相似文献