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异质性荧光染色的巨噬细胞功能研究I.异质性荧光染色的巨噬细胞吞噬活性 总被引:1,自引:1,他引:0
利用淀粉多糖和免疫促进剂(白喉类毒素和卡介苗)诱导和活化小鼠腹腔巨噬细胞,观察了四种异质性荧光染色的巨噬细胞非特异性和特异性吞噬活性。实验证明,深蓝色和淡蓝色荧光的巨噬细胞是分化程度低的幼稚细胞,非特异性吞噬功能较弱,但在特异性吞噬过程中呈现了活跃的吞噬活性,特别是在免疫促进剂的活化下,它们的特异性吞噬功能显著增强、淡蓝绿色荧光的巨噬细胞是分化程度较高、非特异性和特异性吞噬功能最旺盛的巨噬细胞,而黄色荧光的巨噬细胞是分化程度最高、特异性吞噬功能较减退的巨噬细胞。 相似文献
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本实验用免疫印迹法纯化的抗EBNA亚型抗体,结合显微荧光分光光度检测技术,检测在不同感染状态下,三种亚型EBNA抗原在细胞中的表达程度。结果表明,处于潜伏感染状态下的Raji细胞EBNA-1表达量较大,经巴豆油和正丁酸诱导进入钝挫感染状态后EBNA-1表达减少,而EBNA-2的表达增强。B_(95-8)细胞也有相似的趋势。表明EB病毒的激活可能与不同EBNA亚型表达量的改变有关。 相似文献
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Andrea Casasco Marco Casasco Antonia Lcaro Cornaglia Marco Danova Monica Giordano Alberto Calligaro 《Biotechnic & histochemistry》1994,69(2):112-117
PC10 is a monoclonal antibody to proliferating cell nuclear antigen, a nuclear protein associated with the cell cycle. We have evaluated the effects of tissue fixation on PC10 immunoreactivity in sections of paraffin embedded rat tissues. Immunoreactivity was well preserved in tissues after fixation with alcohol-based solutions for 3-24 hr. Fewer PC10-positive cells were detectable in samples fixed with formaldehydecontaining solutions compared with samples fixed with alcohol for the same time. Loss of PC10 immunoreactivity in formaldehyde fixed tissues was progressive, and quantifiable as early as after 3 hr fixation. Consequently, alcohol-based fixatives are strongly recommended for any immunocytochemical prospective study using PC10 antibody. In contrast, loss of PC10-immunoreactivity is always predictable, but difficult to quantitate, using formaldehyde fixed specimens. This aspect should be considered when using PC10 antibody in retrospective studies with routinely-processed archival material. 相似文献
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Identification of a nucleo-cytoplasmic ionic pathway by osmotic shock in isolated mouse liver nuclei
Summary The observation that the nuclear envelope outer mem brane contains ion channels raises the question of whether these conductances
communicate between the cytosol and the nuclear envelope cisternae or between the cytosol and the cytoplasm. Failure to detect
large, nonselective holes using the patch-clamp technique has led to the speculation that ion channels and nuclear pores are
in fact the same.
In this paper we present evidence that the ionic channel, recorded in isolated liver nuclei with the patch-clamp configura
tion of “nucleus-attached,” spans the double membrane of the envelope, providing a direct contact between nucleoplasm and
cytoplasm. 相似文献
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Calcium deficiency in zucchini (Cucurbita pepo L.) is associated with reduced growth and a reduced ability to transport auxin (Allan and Rubery, 1991, Planta 183, 604–612). An investigation of the effects of calcium-deficiency on zucchini hypocotyl cells was made using weak-acid uptake
and 31P-nuclear-magneticresonance (31P-NMR) spectroscopy in vivo and in tissue extracts. Calcium-deficient tissue had the same cytoplasmic and vacuolar pHs as
normal tissue when extracellular pH was near neutral. At acidic external pH the vacuolar pH was lower in deficient tissue.
Adenine nucleotides were present predominantly as ATP in both control and calcium-deficient tissues. Addition of calcium to
calcium-deficient tissue, under conditions which cause recovery of auxin transport induced no changes in the 31P-NMR spectra of deficient tissue. The content of mobile, phosphorylated metabolites was reduced in calcium-deficient tissue
in comparison to control tissue. However, a substantial increase in the content of phosphorylcholine occurs in calcium-deficient
tissues compared with controls; this may reflect changes in lipid turnover in calcium-stressed cells.
We wish to thank Drs. Terry Moore and Jamie Vandenberg for technical assistance and Professor Peter Morris for providing the
gated oxygen device. A.C.A. thanks the Cambridge Commonwealth Trust for a Prince of Wales Scholarship and the O.R.S. Awards
Scheme for an award. 相似文献