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931.
HBsAg阴性母亲的新生儿接种不同剂量乙型肝炎血源疫苗的效果 总被引:2,自引:0,他引:2
HBsAg阴位母亲的新生儿,按0,1、6月程序分别接种10-10-10μg(1组)、20-10-10μg(2组)和30-10-10μg(3组)乙型肝炎血源疫苗。第一针后一年,检查抗-HBs阳转率,分别为87.60%,90.64%和88.97%,无统计学显著差异。3针10μg组免疫后l~4年抗-HBs阳性率分别为88.31%、81.08%、80.10%和78.39%,虽稍下降,但无统计学显著差异。3个剂量组HBsAg阳性率分别为0.71%,0.49%和0.74%,说明HBsAg阴性母亲的新生儿,用国产血源HBsAg疫苗免疫以10μ×3效果较理想。 相似文献
932.
摩尔达维亚苏维埃社会主义共和国位于苏联欧洲部分的西南端。面积33,700平方公里,人口370多万。境内丘陵与河谷平原相间。中部为高地,巴拉湟什特海拔达429米。高地南、北均成倾斜平原。土壤以黑土为主,占75%;棕色和灰色森林土约占10%,遍布中部高地;沿河滩地为冲积草甸土。气候温和,属中 相似文献
933.
934.
Ribonuelease activity and its isozyme pattern of mung bean cotyledon segment were determined during dedifferentiation. The results showed that the activity of ribonuelease in the dedifferentiated tissue is higher than that of control, three new bands of isozyme appear during callus formation. Addition of cycloheximide (CHM) at 0 or 24 hours inhibits either the enzyme activity or the appearance of new bands. These facts indicate that the changes of ribanuelease are at translation level. 相似文献
935.
慢性缺氧大鼠肺动脉一氧化氮合酶与蛋白激酶C表达变化关系的免疫组织化学研究 总被引:2,自引:0,他引:2
观察慢性缺氧对大鼠肺动脉诱导型一氧化氮合酶 (i NOS)和蛋白激酶 C (PKC)表达的影响 ,并探讨 i NOS及 PKC的相互关系在肺动脉高压形成中的作用。建立常压缺氧肺动脉高压模型。应用免疫组化染色和计算机定量图像分析技术观察各组 i NOS和 PKC在蛋白质水平表达的变化 ,并分析二者之间的关系。结果表明随着缺氧时间的延长 ,PKC的表达逐渐上升而 i NOS的表达逐渐下降 ,直线相关分析结果呈显著性负相关 (n=2 4,r=- 0 .94,P<0 .0 1) ,提示 i NOS与 PKC相互拮抗作用与缺氧性肺动脉高压的形成及发展有关 相似文献
936.
Sphingomyelinase enhances low density lipoprotein uptake and ability to induce cholesteryl ester accumulation in macrophages. 总被引:8,自引:0,他引:8
Cholesteryl ester-loaded macrophages, or foam cells, are a prominent feature of atherosclerotic lesions. Low density lipoprotein (LDL) receptor-mediated endocytosis of native LDL is a relatively poor inducer of macrophage cholesteryl ester accumulation. However, the data herein show that in the presence of a very small amount of sphingomyelinase, LDL receptor-mediated endocytosis of 125I-LDL was enhanced and led to a 2-6-fold increase in 125I-LDL degradation and up to a 10-fold increase in cholesteryl ester accumulation in macrophages. The enhanced lipoprotein uptake and cholesterol esterification was seen after only approximately 12% hydrolysis of LDL phospholipids, was specific for sphingomyelin hydrolysis, and appeared to be related to the formation of fused or aggregated spherical particles up to 100 nm in diameter. Sphingomyelinase-treated LDL was bound by the macrophage LDL receptor. However, when unlabeled acetyl-LDL, a scavenger receptor ligand, was present during or after sphingomyelinase treatment of 125I-LDL, 125I-LDL binding and degradation were enhanced further through the formation of LDL-acetyl-LDL mixed aggregates. Experiments with cytochalasin D suggested that endocytosis, not phagocytosis, was involved in internalization of sphingomyelinase-treated LDL. Nonetheless, the sphingomyelinase effect on LDL uptake was macrophage-specific. These data illustrate that LDL receptor-mediated endocytosis of fused LDL particles can lead to foam cell formation in cultured macrophages. Furthermore, since both LDL and sphingomyelinase are present in atherosclerotic lesions and since some lesion LDL probably is fused or aggregated, there is a possibility that sphingomyelinase-treated LDL is a physiologically important atherogenic lipoprotein. 相似文献
937.
Interest in altered ether-lipid metabolism, associated with peroxisomal disorders including adrenoleukodystrophy and Zellweger's syndrome, has highlighted present limitations in our understanding of the biosynthesis and turnover of plasmalogens. These 1-alkenyl ethanolamine phosphoglycerides are major phospholipids in brain, vascular tissue, neutrophils, and most tumors, and they constitute 15-20% of total phospholipids in cultured glioma cell. In glioma, turnover of polyunsaturated acyl chains in the sn-2 position of plasmalogens was examined in relation to selectivity for the (n - 3) and (n - 6) families. Remodeling of acyl chains was more dependent on chain length than on selectivity between families, consistent with plasmalogens enriched in polyunsaturated, but not specifically (n - 3), fatty acids. Extracellular serine was a precursor of serine and ethanolamine phosphoglycerides and was associated with plasmalogens due to decarboxylation and headgroup exchange. Incorporation of extracellular serine ceased within 8 h, even though more than 50% of the label remain in the medium. Analyses of medium and cellular water-soluble components indicated rapid conversion of serine to glycine and other metabolites not used in phospholipid biosynthesis. Thus, nutrient molecules as precursors of plasmalogens are involved in complex competitive interactions. As functions of plasmalogens are clarified, regulation of plasmalogen turnover becomes an increasingly important issue and elucidation of these processes is essential. 相似文献
938.
We have used a Mus domesticus/-Mus spretus congenic animal that was selected for retention of Mus spretus DNA around the pearl locus to create a highly polymorphic region suitable for screening new markers. Representation difference
analysis (RDA) was performed with either DNA from the congenic animal or C57BL/6J as the driver for subtraction. Four clones
were identified, characterized, and converted to PCR-based polymorphic markers. Three of the four markers equally subdivide
a 10-cM interval containing the pearl locus, with the fourth located centromeric to it. These markers have been placed on
the mouse genetic map by use of an interspecific backcross panel between Mus domesticus (C57BL/6J) and Mus spretus generated by The Jackson Laboratory.
Received: 12 June 1995 / Accepted: 17 August 1995 相似文献
939.
Callus formation from protoplasts of Artemisia sphaerocephala Krasch and some factors influencing protoplast division 总被引:2,自引:0,他引:2
Round wormwood (Artemisia sphaerocephala Krasch) seeds were germinated on Murashige & Skoog (1962) medium without plant growth regulators. The hypocotyls of seedlings were sliced and cultured on M1 medium with 2,4-dichlorophenoxyacetic acid (9.05 M) to induce callus. The induced calluses were subcultured on the same medium. Ten day old calluses were used to isolate protoplasts in an enzyme solution with 0.65 M mannitol. Protoplast yield strongly depended upon the state of callus cultures. Certain amount of hemicellulase could improve protoplast isolation. Purified protoplasts were cultured in modified Kao & Michayluk (1975) medium with 0.60 M mannitol as osmoticum, suggesting that protoplasts of A. sphaerocephala need a high initial osmolarity. Protoplasts generally divided evenly and the percentage of first division could reach 10%. Kinetin exhibited a positive effect on initial cell division. Furthermore, we studied the effect of protoplast density and vitamin C on sustained growth of protoplasts. After forty days, 1 mm calluses in diameter formed.Abbreviations CH
casein hydrolysate
- 2,4-D
2,4-dichlorophenoxyacetic acid
- KM8P
Kao & Michayluk (1975) protoplast medium
- MS
Murashige & Skoog (1962) medium
- MES-2
(N-morpholino)ethanesulfonic acid 相似文献
940.