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991.
992.
目的探讨CD28分子在蕈样肉芽肿发病机制中的作用。方法15例蕈样肉芽肿病人,分别采用免疫组织化学ABC方法检测皮损组织,流式细胞仪检测外周血淋巴细胞上的CD28分子表达水平。结果免疫组化结果显示蕈样肉芽肿组皮损中CD28表达明显增多,与正常人对照组相比差异均有显著性(t=4.53,P<0.01)。流式细胞仪检测显示MF外周血淋巴细胞上CD28 T淋巴细胞低于正常对照组(t=16.12,P<0.001)。MF外周血CD8 -CD28 T淋巴细胞低于正常对照组(t=4.925,P<0.001)。结论CD28分子在蕈样肉芽肿发病过程中起一定的作用。  相似文献   
993.
臭牡丹全草化学成分的研究(一)   总被引:6,自引:0,他引:6  
从臭牡丹全草的乙醇提取物的脂溶性部分分离得到三个单一尬发,经理化常数和波谱分析证明,化全物1为新化合物臭牡丹甾醇(bungesterol),化合物Ⅱ为桢桐酯(clerodone),化合物Ⅲ为α-香树脂醇(α-amyrin),均为首次从该植物中得到。  相似文献   
994.
Peng  Yawen  Guo  Genhua  Shu  Bin  Liu  Daiqiang  Su  Peng  Zhang  Xuming  Gao  Feng 《Neurochemical research》2017,42(11):3254-3267

CX3CL1 (fractalkine), the sole member of chemokine CX3C family, is implicated in inflammatory and neuropathic pain via activating its receptor CX3CR1 on neural cells in spinal cord. However, it has not been fully elucidated whether CX3CL1 or CX3CR1 contributes to the development of morphine tolerance. In this study, we found that chronic morphine exposure did not alter the expressions of CX3CL1 and CX3CR1 in spinal cord. And neither exogenous CX3CL1 nor CX3CR1 inhibitor could affect the development of morphine tolerance. The cellular localizations of spinal CX3CL1 and CX3CR1 changed from neuron and microglia, respectively, to all the neural cells during the development of morphine tolerance. A microarray profiling revealed that 15 members of chemokine family excluding CX3CL1 and CX3CR1 were up-regulated in morphine-treated rats. Our study provides evidence that spinal CX3CL1 and CX3CR1 may not be involved in the development of morphine tolerance directly.

  相似文献   
995.
Acetylcholinesterase (AChE) plays a key role in terminating neurotransmission at cholinergic synapses. AChE is also found in tissues devoid of cholinergic responses, indicating potential functions beyond neurotransmission. It has been suggested that AChE may participate in development, differentiation, and pathogenic processes such as Alzheimer's disease and tumorigenesis. We examined AChE expression in a number of cell lines upon induction of apoptosis by various stimuli. AChE is induced in all apoptotic cells examined as determined by cytochemical staining, immunological analysis, affinity chromatography purification, and molecular cloning. The AChE protein was found in the cytoplasm at the initiation of apoptosis and then in the nucleus or apoptotic bodies upon commitment to cell death. Sequence analysis revealed that AChE expressed in apoptotic cells is identical to the synapse type AChE. Pharmacological inhibitors of AChE prevented apoptosis. Furthermore, blocking the expression of AChE with antisense inhibited apoptosis. Therefore, our studies demonstrate that AChE is potentially a marker and a regulator of apoptosis.  相似文献   
996.
BACE蛋白的表达、纯化和活性测定   总被引:2,自引:0,他引:2  
在大肠杆菌中表达、纯化并重新折叠以获得有活性的酸性蛋白水解酶 (BACE蛋白 )———一种与阿尔茨海默病 (AD)发病相关的蛋白水解酶。克隆BACE活性区的表达序列到原核表达载体 pET11a中 ,经E .coliBL2 1(DE3)表达 ,从包涵体中获取蛋白质 ,电泳鉴定后经梯度反向快速折叠法重新折叠 ,柱层析分离纯化 ,得到了表达的重组可溶性BACE蛋白 ;用高效液相色谱、质谱等方法检测其对人工合成多肽底物的水解作用 ;测定了BACE蛋白的酶促动力学常数。结果表明 ,得到的重组BACE蛋白具有水解人工合成小肽底物的活性。  相似文献   
997.
The gene mel1, encoding alpha-galactosidase in Schizosaccharomyces pombe, and the gene bgl2, encoding and beta-glucosidase in Trichoderma reesei, were isolated and co-expressed in the industrial ethanol-producing strain of Saccharomyces cerevisiae. The resulting strains were able to grow on cellobiose and melibiose through simultaneous production of sufficient extracellular alpha-galactosidase and beta-glucosidase activity. Under aerobic conditions, the growth rate of the recombinant strain GC 1 co-expressing 2 genes could achieve 0.29 OD600 h(-1) and a biomass yield up to 7.8 g l(-1) dry cell weight on medium containing 10.0 g l(-1) cellobiose and 10.0 g l(-1) melibiose as sole carbohydrate source. Meanwhile, the new strain of S. cerevisiae CG 1 demonstrated the ability to directly produce ethanol from microcrystalline cellulose during simultaneous saccharification and fermentation process. Approximately 36.5 g l(-1) ethanol was produced from 100 g of cellulose supplied with 5 g l(-1) melibose within 60 h. The yield (g of ethanol produced/g of carbohydrate consumed) was 0.44 g/g, which corresponds to 88.0% of the theoretical yield.  相似文献   
998.
999.
本研究采用SDS—PAGE分析了冀麦七号、冀麦18和冀早15三个品种激光后代籽粒贮藏蛋白的变异情况。结果表明,高分子量麦谷蛋白和醇溶蛋白亚基变异较小,其控制位点为Glu—1和Gl—3或Gli—1;而低分子量部分变异较大,其控制位点多在Glu—3、Gli—2和Gli—3。这些变异具有一定的随机性。有关激光诱变对小麦面粉品质的影响有待进一步研究。  相似文献   
1000.
HIC-1 is a gene that is hypermethylated in cancer, and commonly downregulated in human breast cancer. However, the precise mechanisms and molecular pathways regulated by HIC-1 remain unclear. We assessed HIC-1 expression on a tissue microarray containing 80 cases of breast cancer. We also analyzed its biological function by restoring HIC-1 expression using 5-aza-2′ deoxycytidine (5-CdR) and small-activating RNAs for the reversal of HIC-1 tumor suppressive effects on MCF-7 and MDA-MB-231 cell lines. An Agilent Q44h global expressing microarray was probed after restoring the expression of HIC-1. Data demonstrated that HIC-1 expression was reduced significantly in breast cancer tissues. HIC-1 immunohistochemistry resulted in mean staining scores in cancer tissue and normal ductal epithelia of 3.54 and 8.2, respectively (p<0.01). 5-CdR partially reversed HIC-1 expression, and modulated cell growth and apoptosis. dsHIC1-2998, an saRNA, showed activating efficacy in breast cancer cells. A group of differentially expressed genes were characterized by cDNA microarray. Upon saRNA treatment, genes upregulated included those involved in immune activation, cell cycle interference, the induction of apoptosis, anti-metastasis, and cell differentiation. Downregulated genes included oncogenes and those that play roles in cell invasion, cell growth, and cell division. Our findings may provide valuable resources not only for gene functional studies, but also for potential clinical applications to develop novel drug targets.  相似文献   
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