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71.
Patients with hairy cell leukemia (HCL) and chronic lymphocytic leukemia (CLL) were treated with recombinant interferon alpha A (rIFN- alpha A). The binding of iodinated recombinant interferon-alpha to baseline samples of peripheral blood mononuclear cells (PBMCs) from the leukemia patients was compared with clinical responsiveness to rIFN- alpha A. HCL patients (8/10) responded to rIFN-alpha A therapy, whereas none (0/10) of the CLL patients studied responded. The PBMCs from the eight responsive HCL patients bound approximately twice as much iodinated interferon as the PBMCs from nonresponsive CLL patients. This difference was due to more high-affinity receptors per cell with no difference in the affinity of the interferon-receptor interaction. However, because PBMCs from HCL patients were larger than PBMCs from CLL patients, the cell surface receptor density was similar. The leukemic cells from one of the two nonresponsive HCL patients bound iodinated interferon similarly to the cells from the responsive HCL patients, whereas the leukemic cells from the other nonresponsive HCL patient bound considerably less. The rapidity of response of the HCL patients did not correlate with the level of binding of iodinated interferon. Our results suggest that the absolute number of interferon receptors per cell may be only one of several important parameters in the response to rIFN-alpha A therapy, and that the responsiveness of a particular lymphoproliferative disease or a particular patient to rIFN- alpha A therapy cannot be predicted or explained solely by the degree of interaction between IFN and its cell surface receptor.  相似文献   
72.
BMP2,3,4,5 mRNA在三叉神经中的表达分析   总被引:1,自引:0,他引:1  
目的:明确 B M Ps 与外周神经的关系。方法:用原位杂交方法观察 B M P2,3,4,5 的m R N A在三叉神经中的表达。结果:在外周神经(三叉神经)中均有 B M P2,3,4,5 m R N A 分布, B M P2,3,4,5 的分布主要位于构成神经纤维髓鞘的雪旺细胞中;此外发现 B M P2 在部分神经纤维中也有表达。结论:首次确定了 B M P2,3,4,5 在外周神经中的表达和分布,揭示了 B M P2,3,4,5可能在外周神经的发育和再生以及形态结构的维持中发挥着调控作用。  相似文献   
73.
OBJECTIVES: Ameloblastomas appear to exhibit biological heterogeneity and, except in the case of malignancy, histological appearances that do not always allow their behaviour to be predicted. The aim of this study was to assess keratin expression in African ameloblastomas and to correlate this with their clinical and histological features. MATERIALS AND METHODS: Expression of simple keratins 7, 8, 18 and 19; cornification keratins 1 and 10; basal and differentiation keratins 5 and 14 and hyperproliferation-related keratins 6 and 16 in 14-39 cases of ameloblastoma was assessed by immunohistochemical methods. RESULTS: There was patchy expression of keratin 7 in the suprabasal and stellate reticulum-like cells in some cases. All cases showed similar weak expression for keratins 8 and 18 in suprabasal and stellate reticulum-like cells but none showed keratin 1 or 10 expression. There was intense expression of keratins 5, 14 and 19 by all tumour cells suggesting that they may retain basal cell characteristics with a potential for proliferation. No consistent relationship was seen between histological types and keratin expression pattern. However, keratins 6 and 16, expressed by suprabasal and stellate reticulum-like cells, showed a marked variation within and between cases, with the highest levels of expression in squamous strands. CONCLUSIONS: We propose that squamous strands may represent the sites of most active growth within individual tumours and expression of keratins 6, 16 and 19 may be predictors of rapid growth. There is a need for further investigation of this in longitudinal clinical studies.  相似文献   
74.
During the course of differentiation of early human myeloid cells toward monocytes and granulocytes, cell surface expression of the cell adhesion molecule, CD11b/CD18 (Mo1) increases dramatically and expression of myeloperoxidase (MPO), a bacteriocidal enzyme, decreases markedly. Using the inducible promyelocytic cell line HL-60 as a model, we studied the mRNA expression of these genes. Differentiation of these cells along both a monocytic and a granulocytic pathway demonstrated that the mRNA levels of the two subunits of CD11b/CD18 increased in a pattern temporally and quantitatively similar to the increase in cell surface expression of this heterodimer. In contrast, the expression of MPO mRNA decreased in a temporal and quantitative pattern similar to the known decrease in MPO protein during differentiation, suggesting that regulation of these myeloid-specific proteins may occur at the level of mRNA expression. These findings have important implications with regard to the nature of the block in differentiation in acute nonlymphocytic leukemia and the regulation of myeloid gene expression.  相似文献   
75.
HPLC柱切换法测定血浆和尿样中头孢克肟浓度   总被引:8,自引:0,他引:8  
用双泵HPLC柱切换系统直接进样测定血浆和尿样中头孢克肟(cefixime,CFIX)的浓度。血浆和尿样的回收率分别为99.1%和98.6%;最低检测浓度分别为0.05和0.2μg/ml;日内和日间的RSD小于5%;血浆和尿样浓度分别在0.1~3.2和1.0~32μg/ml范围内呈线性相关。此方法集样品净化、富集成分和色谱分析一次连续进行,操作简便、快速,可以进较大的样品量,灵敏度相对明显提高。  相似文献   
76.
高建华  文广伶  张其楷 《药学学报》1990,25(12):891-897
研究了强效抗胆碱药dl-3-(2-苯基-2-环戊基-2-羟基-乙氧基)-奎宁环烷的四个光学异构体的两种不对称合成方法,用HPLC检测了异构体含量,讨论了构效关系。  相似文献   
77.
78.
AIM:The present study was undertaken to isolate and standardize the various active phytochemical constituents present in the fruit rinds of Punica granatum.METHODS:Fruit rinds of Punica granatum were dried and extracted with methanol in a static extractor;the percentage yield of the methanolic extract (MEPG) was found to be 26%;the methanolic extract was partitioned using n-butanol,ethyl acetate and water;the percentage yield of the fractions were found to be 17.16%,26.88% and 47.72% respectively.HPLC was c...  相似文献   
79.
80.
Cytokine networks in destructive periodontal disease   总被引:1,自引:0,他引:1  
GL Howells 《Oral diseases》1995,1(4):266-270
BACKGROUND Cytokines are important regulatory proteins, produced by activated cells, which act by binding high affinity cell surface receptors. They are involved in almost all aspects of cell biology and form interacting networks, with cascades of sequential cell activation. They often show overlapping activities ( redundancy ) or the same cytokine may have a variety of different effects (pleiotropy). In excess, certain cytokines are damaging and proinflammatory. Tumour necrosis factor a (TNFα) and interleukin-I (IL-I) are markedly proinflammatory, inducing bone resorption, collagenase and prostaglandin E2 production.
OBJECTIVE: This paper focuses on the role of TNFa and IL-l in the cytokine networks of destructive chronic per-iodontitis; specifically their regulation by T cell cytokines, receptor antagonists and inhibitory soluble forms of the IL-l and TNF receptors.
CONCLUSION: A hypothesis is proposed that destructive periodontal disease may be due to disregulation of these inhibitors, rather than an overproduction of IL-l and TNFα per se.  相似文献   
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