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111.
112.
结扎大鼠一侧输尿管,复制肾盂积水模型。在冷光源-光导纤维-导光棒的透射照明下,通过显微电视系统,成功地观察到完整肾脏皮质表层肾小球及其周围血管微血流动态的清晰图像。正常肾小球呈树状分布,密集、大小均匀。高倍镜下可清楚辨认入球及出球小动脉,其血细胞流态为直线状。并发现肾小球有交替开放现象。 相似文献
113.
硒对培养人胚肝细胞Ⅲ型前胶原,羟脯氨酸合成的影响 总被引:7,自引:0,他引:7
原代培养人胚肝细胞经1.156×10 ̄(-7)mol/L硒预处理4h,加入20mmol/L四氟化碳作用20h,观察硒对其Ⅲ型前胶原(PCⅢ)和羟脯氨酸(Hyp)生成的影响。结果培养液中PCⅢ水平、细胞内Hyp含量及细胞内外丙二醛(MDA)水平均降低,与未加硒对照组比较差别有显著性(P<0.01)。而硒谷腕甘肽过氧化物酶(Se-GSH-PX)活性则较对照组显著增高(P<0.001),且PCⅢ水平与Se-GSH-P_X/MDA比值呈负相关(r=-0.9156,P<0.01)。提示硒可提高Se-GSH-P_X/MDA比值,抑制脂质过氧化激发的肝细胞胶原合成。 相似文献
114.
115.
116.
大鼠正中神经一级传入纤维在脊髓胶状质定位投射的定量分析——FRAP法 总被引:1,自引:0,他引:1
本文用抗氟化物酸性磷酸酶(FRAP)法和显微测量,对大鼠正中神经一级传入纤维在脊髓胶状质(SG)的定位投射进行了定量分析.大鼠正中神经向SG的纵向投射主要为C_5~T_1.C_5~T_1各节段SG水平向眉毛状反应带所测均值(mm)分别为0.888、0.935、0.957、0.905和 0.776,而正中神经向C_5~T_1各节段SG水平向投射所测均值(mm)分别在0~0.204、0~0.303、0~0.409、0~0.432和0~0.336的范围,这显示了正中神经投射区均位于SG的内侧带和部分中间带. 相似文献
117.
鸦胆子抗肿瘤活性成分的化学研究 总被引:6,自引:0,他引:6
从苦木科植物鸦胆子[Brucea javanica(L.)Merr]干躁果实的硅胶干柱柱层析所得的活性部位中经层析分离得到7个四环三萜苦木内酯成份(A,B,C,D,E,F,G),经UV,IR,~1H-NMR,~(13)C-NMR等方法鉴定分别为鸦胆苦醇(Brusatol A),双氢鸦胆苦醇(Dihydrobrusatol,B),鸦胆因B(Bruceine B,C),鸦胆因D(Bruceine D,D),鸦胆因H(Bruceine H,E),鸦胆子甙A(Bruceoside A,F)和双氢鸦胆子甙A(Yadanzioside A,G)。据报道,鸦胆苦醇和鸦胆子甙A具有较强的抗肿瘤活性。 相似文献
118.
Expression of Bcl-2 protein in the epiphyseal plate cartilage and trabecular bone of growing rats 总被引:2,自引:0,他引:2
Ying Wang Renée Toury Michelle Hauchecorne N. Balmain 《Histochemistry and cell biology》1997,108(1):45-55
The protooncogene protein, Bcl-2, protects cells from apoptosis and ensures their survival in vitro by inhibiting the action
of the apoptosis-inducer, Bax. Its expression in proliferative and long-lived cells in vivo also indicates that it protects
against cell death. The chondrocytes of the epiphyseal plate cartilage undergo a series of maturation steps and deposit mineral
in the cartilage matrix before dying. The possibility that Bcl-2 helps protect chondrocytes until mineral deposition is completed
was investigated by determining the distribution of Bcl-2 immunoreactivity in the epiphyseal plate cartilage of growing rats
and its subcellular localization, using a specific antibody. The involvement of Bax in the triggering of chondrocyte death
was checked by immunocytochemistry. Bcl-2 expression in the osteoblasts and the final result of their evolution, the osteocytes,
was also examined in trabecular bone. Bcl-2 immunoreactivity was non-uniformly distributed throughout the epiphyseal cartilage.
It was maximal in proliferative chondrocytes, decreased in mature chondrocytes, and low in hypertrophic chondrocytes, whereas
there was Bax immunoreactivity in all chondrocytes examined. Immunolabeling was intense in osteoblasts but considerably lower
in fully differentiated osteocytes. Bcl-2 immunoreactivity was mainly in the cytoplasm of chondrocytes, osteoblasts, and early
osteocytes; the nuclei appeared clear. The subcellular distribution of Bcl-2 immunolabeling in chondrocytes, revealed by gold
particles in the electron microscope, showed that gold particles were frequently concentrated in the mitochondria in all the
cartilage zones and lay mainly within the organelles, not at their periphery. The endoplasmic reticulum contained moderate
immunoreactivity and there were few gold particles in the cytoplasm and nuclei. The number of gold particles decreased in
all the subcellular compartments from proliferative to hypertrophic chondrocytes. In contrast, Bax immunoreactivity changed
little during chondrocyte terminal evolution, and its subcellular distribution mirrored that of Bcl-2. These immunocytochemical
data indicate that Bcl-2 helps maintain chondrocytes and osteoblasts until their terminal maturation.
Accepted: 19 February 1997 相似文献
119.
Characterization of a plasma membrane-associated phosphoinositide-specific phospholipase C from soybean 总被引:12,自引:1,他引:11
Jinrui Shi Robert A. Gonzales Madan K. Bhattacharyya 《The Plant journal : for cell and molecular biology》1995,8(3):381-390
Phosphoinositide-specific phospholipase C (PI-PLC) is a key signal transducing enzyme which generates the second messengers inositol trisphosphate and diacylglycerol in mammalian cells. A cDNA clone (PI-PLC1) encoding a phosphoinositide-specific phospholipase C was isolated from soybean by screening a cDNA expression library using an anti-(plasma membrane) serum. Genomic DNA gel blot analysis suggested that the corresponding gene is a member of a multigene family. The deduced amino acid sequence of the soybean PI-PLC1 isozyme contains the conserved X and Y regions, found in other PI-PLCs. It is closely related to mammalian δ-type PI-PLCs, Dictyostelium discoideum PI-PLC and yeast PI-PLC1 in terms of the arrangement of the conserved region. Unlike mammalian δ-type PI-PLCs and yeast PI-PLC1, the putative Ca2+ -binding site of the soybean PI-PLC1 is located in the region spanning the X and Y domains, and the N-terminal region is truncated. FLAG epitope-tagged PI-PLC1 fusion protein purified from transgenic tobacco plants showed phosphoinositide-specific phospholipase C activity. Heterologous expression of the soybean PI-PLC1 cDNA in a yeast PI-PLC1 deletion mutant complemented the lethality phenotype of haploid PI-PLC1 disruptants. Immunoblot analysis of the cell fractions prepared from transgenic tobacco plants over-expressing the FLAG epitope-tagged PI-PLC1 fusion protein indicated that the protein encoded by the PI-PLC1 cDNA was localized in the cytosol and plasma membrane. 相似文献
120.
IL-6受体结构与功能的研究进展 总被引:1,自引:0,他引:1
IL-6是一个多功能的细胞因子,其生物学作用在很大程度上受IL-6受体(IL-6R)结构和功能的影响。IL-6R由两条多肽链组成,即配体结合链gp80和信号传导链gp130。它们在结构和功能上既有分工又有合作。两种亚基组成的高和力IL-6R是介导细胞效应所必需的。IL-6Rα中的造血功能区属于造血因子受体超家族成员,它决定着结合IL-6的能力,然而gp130则是多种细胞因子共用的信号传递分子,其胞 相似文献