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1.
阿霉素铁(Ⅲ)配合物与DNA结合作用的研究   总被引:2,自引:0,他引:2  
应用吸收光谱法研究了阿霉素铁(Ⅲ)[ADM·Fe(Ⅲ)]与DNA的结合作用,结果表明ADM·Fe(Ⅲ)作为一个整体嵌入DNA碱基之间形成ADM·Fe(Ⅲ)·DNA三元复合物。应用荧光淬灭法得到了不同Na+浓度下ADM及ADM·Fe(Ⅲ)与DNA结合作用的结合常数(K)、结合位点距离(n)及标准自由能(ΔG),并根据多聚电解质理论将ΔG分解为电荷作用部分(ΔGpe)及非电荷作用部分(ΔGt)。结果表明ADM·Fe(Ⅲ)中铁离子直接参与了与DNA的作用,ADM·Fe(Ⅲ)较ADM更易与DNA结合,且结合更为紧密  相似文献   

2.
四种抗脂肪肝物质降低草鱼肝胰脏脂质积累的替代关系   总被引:17,自引:0,他引:17  
采用11种添加不同水平的蛋氨酸(Met),胆碱(Ch)甜菜碱(Bet)和大豆卵磷脂(Lec)的饲料饲养初始体重约15g的草鱼,研究了它们降低草鱼肝胰脏脂质积累的相互替代关系,11种饲料中这四种物质的含量分别为(%):(1)1.1Met0.08Ch,(2)1.1Met0.33Ch,(3)1.3Met0.23Ch,(4)1.5Met0.13Ch,(5)1.3Met0.13Ch,(6)1.3Met0.1  相似文献   

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综述了中国木兰科10属的次生木质部解剖学特征,包括导管分子,纤维管胞和木射线。同时,进一步讨论了其系统演化。这10属分为两亚科,即木兰亚科(Magmoliodae),包括木兰族(Magnolieae)和含笑族(Michelieae Law),木兰族有木莲属(Maglietia Bl.)、华兰木属(Manglietiastrum Law)、木兰属(Magnolia L.)、拟草性木兰属(Parakm  相似文献   

4.
许涛  钱琛  汪远金 《生物学杂志》2000,17(6):24-24,23
用腺嘌呤复制动物性慢性肾功能衰竭(CRF)模型。观察大鼠血浆血尿素氮(BuN)、血肌酐(Cr)、血红蛋白(Hb)、超氧化物歧化酶(SOD)和中分子物质(MMS)总量的变化。结果表明,CRF大鼠血浆BuN、Cr和MMS总量明显升高(P〈0.01)、Hb和SOD含量显著降低(P〈0.01)。提示CRF大鼠MMS总量升高、SOD活性降低。  相似文献   

5.
酸枣的组织培养和植株再生   总被引:8,自引:0,他引:8  
1植物名称酸枣(Zizyphus jujubavar.Spinosa)。2材料类别沂河岸堤自然生长的野生植株上的嫩芽。3培养条件诱导愈伤组织培养基:(1)MS+6-BA2mg·L’(单位下同)+NAA0.1;(2)MS+6-BA2+NAA0.2;(3)MS+6.BA2+NAA0.4;(4)MS+6.BA2+NAA1;(5)MS+6.BA2+NAA0.01;(6)MS+6.BA2+NAA0.05;(7)MS+6-BAI+NAA0.5。芽分化培养基:(8)MS+6-BAI;(9)MS+6-BA2;(…  相似文献   

6.
猪肥大细胞的超微结构研究   总被引:6,自引:0,他引:6  
许乐仁  江萍 《动物学研究》1996,17(2):103-107
对4头一月龄长白仔猪的肠粘膜肥大细胞(MMC)、粘膜下结缔组织肥大细胞(CTMC)及胸腺髓质肥大细胞(TMMC)进行了透射电镜观察。未发现它们之间存在超微结构的显著差异。  相似文献   

7.
宫粉郁金的组织培养和快速繁殖   总被引:8,自引:1,他引:7  
1植物名称宫粉郁金(Curcuma kwangsiensis)。2材料类别 块茎萌动芽。3培养条件 萌动芽生长培养基:(1)MS+6-BA1mg·L-1(单位下同)+NAA0.2。不定芽增殖与愈伤组织诱导培养基:(2)MS+6-BA10+KT5;(3)MS+6.BA10;(4)MS+6-BA5+KT2.5;(5)MS+6-BA5;(6)MS+6-BA2+KT1。生根培养基:(7)MS+NAA0.5;(8)MS+6-BA0.5+NAA0.5;(9)MS。以上培养基均加0.7%琼脂,3%蔗糖,pH5…  相似文献   

8.
野生经济植物资源橡籽仁可利用价值的研究   总被引:2,自引:0,他引:2  
以京白种鸡作鸡作试验动,以玉米、稻谷作对照,采用鸡真代谢能(TME)法研究野生经济植物资源橡胶籽仁的可利用营养价值。结果表明,橡籽仁1kg含量总能(GE)16.53MJ,表观代谢能(AME)11.13MJ,真代谢能(TME)11.66MJ,,含粗蛋白(CP)10.63%,CP的表观利用率(CPAA)45.55%,真利用率(CPTA)49.83%,17种氨基酸(AA)总含量9.23%,必需氨基酸(E  相似文献   

9.
根据锤头核酶模型,设计合成了一个以黄瓜花叶病毒(CMV)外壳蛋白(CP)亚基因组RNA为底物的锤头型核酶(RZC),在证明它能有效切割该底物后,再将这个核酶与一个能专一性切割烟草花叶病毒(TMV)移动蛋白(MP)亚基因组RNA的锤头型核酶(RZ1)相互串联构成了一个双价核酶(RZ1C),体外结果表明,这个双价核酶能与相应的单价核酶RZ1和RZC一样专一而有效地切割CMV CP和TMV MP RNA  相似文献   

10.
根据锤头核酶模型,设计合成了一个以黄瓜花叶病毒(CMV) 外壳蛋白(CP) 亚基因组RNA 为底物的锤头型核酶(RZC) 。在证明它能有效切割该底物后,再将这个核酶与一个能专一性切割烟草花叶病毒(TMV) 移动蛋白( MP) 亚基因组RNA 的锤头型核酶(RZ1) 相互串联构成了一个双价核酶(RZ1C) 。体外结果表明,这个双价核酶能与相应的单价核酶RZ1 和RZC 一样专一而有效地切割CMVCP和TMV MPRNA。  相似文献   

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12.
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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This study aimed to analyze the aqueous humor (AH) and the vitreous body (VB) of the eye of the adult frog Rana temporaria L. as a representative species of amphibians, which lead a semi-terrestrial life. The presence of collagen, albumin, uric acid and electron donors was shown in both media; however, there are slight differences in their concentrations. To determine collagen, a spectral-fluorescent probe, cyanine dye, was used. The presence of collagen in AH of the frog was found at the first time. The total content of electron donors (ascorbic and uric acids, tryptophan, and tyrosine) in VB and HA was roughly estimated at ~ 1.5 × 10− 4 mol/L. Both VB and AH absorb light in similar UV regions. The total protein and albumin contents in AH were found to be somewhat higher than those in VB. The uric acid content was at an equally low level in both intraocular media. It is supposed that the similarity of VB and AH compositions shown in this work is due to some exchange between VB and AH contents in the course of accommodation. The role of intraocular fluids in physiological functions of the eye and in protecting the retina against UV light is discussed.  相似文献   

20.
Summary The choriocapillaris is a fenestrated capillary bed located posterior to the retinal pigment epithelium. It serves as the main source of supply to the photoreceptors, retinal pigment epithelium, and other cells of the outer retina. The permeability of these capillaries to intravenously injected ferritin (MW — approx. 480,000; mol. diam. 11 nm) was examined in the mouse, rabbit, and guinea pig, each of which is characterized by a different type of retinal vascularization. In all three species, the bulk of the ferritin remained in the capillary lumina, where it appeared to be blocked at the level of the diaphragmed fenestrae. Some ferritin was present in endothelial cell vacuoles. The results confirm previous work on the rat choriocapillaris and indicate that the barrier function of the choriocapillary endothelium is present even among species in which the retinal circulation differs significantly.Supported by NIH grant EY03418  相似文献   

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