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1.
中蜂(Apis cerana)蛹期脂肪体营养细胞蛋白质颗粒…   总被引:2,自引:1,他引:1  
本文以差分析法;小角X-射线散射及偏光显微镜等方法证明,中蜂蛹期脂肪体内营养细胞蛋白质颗粒呈液晶态,表现出结构有序的特征。正交偏光下,“蛋白质颗粒”显示出外区具强双折射的马尔它十字消光现象;以DTA等方法测得,液晶态“蛋白质颗粒”在26℃时可向各向同态转变,且具可逆性,由于“蛋白质颗粒”的大量存在,以SAXS直接测定脂肪体,证实中蜂蛹期体内营养细胞液晶态“蛋白质颗粒”的Bragg间距为44A,属于  相似文献   

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为提高DEX对新生儿呼吸窘迫综合征(NRDS)的防治,本文研究了地塞米松(DEX)促进肺表面活性物质(PS)合成的作用机制。用分离培养的20天大鼠胚胎肺泡Ⅱ型细胞为材料,观察了单独用DEX、用与不用DEX刺激后的成纤维细胞条件培养液(DEXFCM、FCM)对肺泡Ⅱ型细胞PS中磷脂合成及特异性肺表面活性物质蛋白质SPB、SPCmRNA表达的影响。结果表明,DEX本身及未用DEX刺激的FCM对肺泡Ⅱ型细胞的上述三种指标均没有影响,而DEX刺激后的DEXFCM使这三个指标有不同程度的增加效应。提示糖皮质激素刺激肺泡Ⅱ型细胞PS合成增加是由成纤维细胞介导的  相似文献   

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中国山西,广西美芒藻属两新种   总被引:1,自引:0,他引:1  
中国山西、广西美芒藻属两新种谢树莲凌元洁(山西大学生命科学系太原030006)TWONEWSPECIESOFCOMPSOPOGON(RHODOPHYTA)FROMSHANXIANDGUANGXI,CHINAXIEShuLianLINGYuanJ...  相似文献   

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黑龙江铜木蚜蝇雌性的描述DESCRIPTIONOFTHEFEMALECHALCOSYRPHUS(XYLOTOMIMA)AMURENSIS(STACKELBERG)(DIPTERA:SYRPHIDAE)¥HEJilong;CHUXiping(Depar...  相似文献   

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非离子型去垢剂Triton X—114提取两歧双歧杆菌的脂磷壁酸   总被引:6,自引:0,他引:6  
本研究利用非离子型去垢剂Triton X-114提取两歧双歧杆菌细胞壁的脂磷壁酸(LTA),DEAE-Sephacel阴离子层垢后,Triton X-114与LTA分开为两个峰,收集LTA洗脱峰,经紫外扫描、化学组分分析证实提取的LTA无明显蛋白质、核酸污染。被动血球凝集试验结果显示,LTA能自主粘附绵羊红血球,并能同抗LTA抗体或抗两歧双歧杆菌抗体结合而使血球凝集。我们采用的方法是分离细胞壁LT  相似文献   

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植物的诱导抗病性   总被引:17,自引:2,他引:15  
植物的诱导抗病性洪剑明邱泽生柴晓清(首都师范大学生物系,北京100037)INDUCEDDISEASERESISTANCEOFPLANTHongJian-mingQiuZe-shengChaiXiao-qing(DepartmentofBiolog...  相似文献   

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植物学教学中的卵菌分类地位   总被引:1,自引:0,他引:1  
钟恒 《植物学通报》1995,12(3):59-61
植物学教学中的卵菌分类地位钟恒(中山大学生物系,广州510275)THETAXONOMICSTATUSOFOOMYCETESINTHEBOTANICALTEACHINGZhongHeng(DepartmentofBiology,ZhongshanUn...  相似文献   

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水分胁迫条件下谷子抗旱生理特性的研究   总被引:7,自引:0,他引:7  
水分胁迫条件下谷子抗旱生理特性的研究程林梅阎继耀张原根张和(山西省农业科学院作物遗传研究所,太原030031)STUDYONDROUGHTRESISTANTPHYSIOLOGICALCHARACTERISTICSOFFOXTAILMILLETUND...  相似文献   

9.
D—半乳糖对神经元和成纤维细胞拟老化作用的实验研究   总被引:21,自引:0,他引:21  
实验用体内、外相结合的方法,观察了D-半乳糖(D-galactose,D-gal.)对细胞的促老化作用。结果表明,D-gal使培养大鼠胎脑神经元出现生长发育缓慢、突起脱落、死亡率增高等退行性变;大鼠肺成纤维细胞的体外分裂代数减少;人胎儿肺二倍体成纤维细胞(HBS)分裂周期中G2-M期细胞减少、G-G1期细胞增加、DNA含量下降,细胞增殖速度减慢;大鼠胎脑神经细胞和HBS中SOD含量降低,丙二醛(MDA)水平升高,这些结果与次黄瞟呤(HPX)-黄瞟呤氧化酶(XOD)系统产生的超氧阴离子自由基(O-2·)作用一致。提示,D-gal抑制细胞生长发育和分裂繁殖,加速细胞老化,其机理可能与O-2·等活性氧(ROS)过荷引起的脂质过氧化有关。  相似文献   

10.
植被类型图的绘制——以西藏植被图为例   总被引:2,自引:0,他引:2  
植被类型图的绘制———以西藏植被图为例田新智(中国科学院植物研究所,北京100093)METHODSINDRAWINGMAPOFVEGETATIONTYPETianXinzhi(InstituteofBotany,ChineseAcademyofS...  相似文献   

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K. Hausmann 《Protoplasma》1979,100(2):199-213
Summary The membranes of the pellicle of the ciliatePseudomicrothorax dubius are investigated using thin section electron microscopy and freeze-fracture replicas. The plasma membrane is covered by a surface coat and is connected to the outer alveolar membrane by short, sometimes branched, bridges. The inner alveolar membrane is coated on both sides. The epiplasm lies in intimate contact with the cytoplasmic surface of this membrane, and there is a corresponding deposit on the other surface. This deposit is regularly striated.The epiplasmic layer and the alveoli are interrupted at sites of cytotic activity,e.g., the attachment sites of trichocysts, the cytoproct, and the parasomal sacs. The striated deposit ends where the epiplasm ends, indicating a direct relationship between these two epimembranous layers.There is a deposit along the sides of the first part of the tip of the trichocysts, and in this region the trichocyst membrane is free of intramembranous particles.The membrane of the parasomal sacs has a coat on both surfaces. That on the extraplasmic surface is similar to the surface coat of the plasma membrane. The origin of the cytoplasmic coat is unknown. The cytotic activity of these sacs is indicated by their highly irregular profiles.  相似文献   

13.
Summary The differentiation of the spermatid, especially in reference to the formation of the flagellum, and transformation of the shape of the nucleus was investigated in the domestic fowl.In the early stage of the spermatid, a prominent Golgi apparatus appears around the centrioles. The Golgi vesicles then surround the axial-filament complex which develops from the distal centriole. These vesicles fuse to form continuous membrane at the earliest stage of flagellar formation, and in the succeeding stage Golgi lamellae are attached to the plasma membrane of the developing flagellum. From these observations, it is assumed that Golgi apparatus may be a source of the membrane system of the flagellum.The microtubules distributed around the nucleus form the circular manchette. The anterior region of the nucleus with the manchette is cylindrical in shape and the posterior region without it remains irregular in shape. When the circular manchette has been completed, the whole nucleus acquires a slender cylindrical shape. The circular manchette then changes into the longitudinal manchette. The nuclei of spermatids without a longitudinal manchette are abnormal in shape. In view of these observations it is assumed that the nuclear shaping of the spermatid may be accomplished by circular manchette and the maintenance of shape of the elongated nucleus by longitudinal manchette.The authors wish to thank Mr. Takayuki Mori for his helpful suggestions and technical advices  相似文献   

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Summary According to light- and electron-microscopic observations the pineal organ of the 3-day-old chicken consists of a prominent end vesicle and a tapering parenchymal stalk. During this stage the pineal lumen is in open communication with the third ventricle. However, in the 40-day-old chicken, which still possesses a well-developed end vesicle, the proximal portion of the pineal stalk displays regressive changes leading to local fragmentation. At this stage the pineal stalk is reduced, and the pineal lumen is missing. In 1-year-old chickens the parenchyma of the proximal portion of the stalk is further diminished, and in 3-year-old domestic fowl is completely displaced by bundles of collagenous fibers, only some nerve fibers being present. This post-hatching pineal development may reflect the sequence of changes leading from pineal sense organs to pineal glands.This work was supported by a grant-in-aid for Scientific Research from the Ministry of Education, Science and Culture of Japan  相似文献   

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