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991.
在构建了含毛细胞白血病相关的结构性倒位inv (5) (p13.1q13.3)的细胞系后,为了确定该新建细胞系在建株过程中其倒位断裂点关键区遗传物质是否发生改变,以生物素或地高辛标记的cCI5-216 和cCI5-267黏粒DNA为探针,进行染色体中期、间期和DNA纤维3种双色荧光原位杂交的分析。结果表明:该新建细胞系的3种双色荧光原位杂交结果,均与该细胞系的原代细胞的完全相同,证实了该细胞系倒位断裂点关键区的遗传物质结构未发生改变。该细胞系是揭示毛细胞白血病发病的分子机理的重要研究材料。 相似文献
992.
红壤茶树根层土壤基础呼吸作用和酶活性 总被引:14,自引:4,他引:14
对不同树龄茶树根层土壤的呼吸作用(包括代谢熵qCO2)和土壤酶(脲酶、转化酶和酸性磷酸单酯酶)活性进行了研究、不同树龄茶树根层土壤日基础呼吸作用强度(36.23—58.52mg·kg^-1·d^-1)和日代谢墒(0.30一0.68)都以40和90年茶树较为接近,分别显著大于和小于10年树龄茶树根层土壤;服酶活性(41.48—47、72mg·kg^-1·d^-1)则三者间差异不大,虽然随树龄增长而下降;转化酶活性(189.29—363.40mg·kg^-1·d^-1)也随树龄增长而下降,并且10年茶树根层土壤显著大于40和90年树龄茶树;而酸性磷酸单酯酶活性(444.22—828.32mg·kg^-1·d^-1)相反,随树龄增长而增强.结果表明,土壤基础呼吸作用、代谢熵和3种土壤酶活性都与茶树树龄、土壤pH、土壤有机碳、土壤全氮、土壤可活性酚总量、及土壤微生物生物量密切相关. 相似文献
993.
福建省耕地土壤重金属含量和可浸提性研究 总被引:8,自引:3,他引:8
测定了福建省6市、县耕地土壤中的Cu、Zn、Cd、Ni、Pb、Hg、As等7种重金属元素的全量和可浸提态含量,并对测定结果进行了数理统计。结果表明,福建省耕地土壤存在着不同程度的重金属污染,但依元素不同而不同,重金属可浸提态含量占全量的10.0?52.2 Cu、Zn、Cd、Pb、Ni的可浸提态含量与全量之间的相关达极显著水平,Zn、Cd、Pb、As等4元素含量之间存在着显著正相关,而Ni则只与Zn元素有极显著正相关,Cu和Hg与其它重金属元素的相关则均不显著。 相似文献
994.
995.
996.
口服型HCV融合抗原DNA疫苗在小鼠诱导免疫应答 总被引:1,自引:0,他引:1
将编码一个外源信号肽、一个通用型辅助性T淋巴细胞抗原表位和HCV核心 包膜蛋白E2融合抗原基因的真核表达质粒pST CE2t(DNA疫苗 )转化到减毒鼠伤寒沙门菌SL72 0 7.将该重组菌口服接种BALB c小鼠 3次 .小鼠的抗HCV核心和E2抗体阳转率分别达 6 0 %和 70 % .体外以重组HCV核心或E2抗原刺激小鼠脾细胞 ,均使之发生明显的增殖反应 ,且小鼠脾细胞能有效杀伤表达HCV核心抗原的同系骨髓瘤细胞SP2 0 .这为研制高效免疫、成本低廉、接种方便的HCV疫苗提供了一个新的可行途径 相似文献
997.
1. AMPA receptor potentiators (ARPs) exhibit antidepressant-like activity in preclinical tests (for example, the forced swim test) that are highly predictive of efficacy in humans. Unlike most currently used antidepressants, ARPs do not elevate extracellular levels of biogenic amines (e.g., 5HT, NE) in prefrontal cortex at doses that are active in the forced swim test.2. The present series of experiments examined the effects of combining the ARP, LY 392098, with biogenic amine-based antidepressants in the forced swim test. Male, NIH Swiss mice were placed in a cylinder of water and observed for attempted escape behaviors and immobility.3. LY 392098 dose-dependently decreased immobility as did a range of classical antidepressants. At doses of LY 392098 below those that decreased immobility, this compound significantly increased the potency with which fluoxetine and citalopram (SSRI antidepressants), imipramine (tricyclic antidepressant), duoxetine (norepinephrine/serotonin uptake blocker), nisoxetine (norepinephrine uptake inhibitor), and rolipram (PDE4 inhibitor) decreased immobility in the forced swim test with potency shifts upward of 5-fold (fluoxetine, imipramine, and rolipram). Likewise, ineffective doses of the traditional antidepressants potentiated the effects LY 392098 with shifts in the dose-effect functions that were 10-fold or more for citalopram, fluoxetine, imipramine, and duloxetine.4. Combined with other evidence for a role of AMPA receptors in the efficacy of antidepressants, the current data suggest that the addition of an ARP may augment the activity and perhaps the onset of the therapeutic effects of biogenic amine and second messenger-based antidepressants. 相似文献
998.
HaploBlockFinder: haplotype block analyses 总被引:8,自引:0,他引:8
Recent studies have unveiled discrete block-like structures of linkage disequilibrium (LD) in the human genome. We have developed a set of computer programs to analyze the block-like LD structures (haplotype blocks) based on haplotype data. Three definitions of haplotype block are supported, including minimal LD range, no historic recombination, and chromosome coverage. Tagged SNPs that uniquely distinguish common haplotypes are identified. A greedy algorithm was used to improve the efficiency. Two separate utilities were also provided to assist visual inspection of haplotype block structure and pattern of linkage disequilibrium. AVAILABILITY: A web interface for the HaploBlockFinder is available at http://cgi.uc.edu/cgi-bin/kzhang/haploBlockFinder.cgi the source codes are also freely available on the web site. 相似文献
999.
P—选择素凝集素—EGF功能域的克隆、表达及其单克隆抗体制备 总被引:19,自引:0,他引:19
制备特异性抗人P 选择素的凝集素 表皮生长因子 (L EGF)功能域的单克隆抗体。利用特异引物 ,通过RT PCR从外周血血小板中扩增出人P 选择素的L EGF功能域基因 ,将其克隆至pET42b( )载体中 ,测序验证后转染大肠杆菌BL2 1,经诱导表达了C端融合 6×His的蛋白质。融合蛋白质经分离纯化后 ,免疫Balb/c小鼠 ,应用杂交瘤技术 ,通过间接ELISA筛选阳性克隆。获得 3株可稳定分泌抗L EGF功能域单抗的杂交瘤细胞株 (B10、F3和H5 )。其亚型分别为IgG2 、IgG1和IgG3;轻链均为κ型。所获的单抗对LPS刺激活化的人脐静脉内皮细胞均有特异性结合反应 ,并可在体外阻断经凝血酶激活的血小板与中性粒细胞间的粘附。表明所获的单抗可特异性识别结合天然P 选择素 ,具有体外抗活化血小板与中性粒细胞粘附的功能 ,为进一步应用此单抗进行P 选择素结构和功能及抗粘附治疗研究提供了实验基础。 相似文献
1000.
Jiaxing Zhang Chenhui Lu Jun Zhang Jiuhong Kang Chuanwu Cao Maoquan Li 《Molecular biology reports》2013,40(2):949-956
This study intended to investigate the expression of the ZEB1 and E-cadherin proteins in lung squamous cell carcinoma (LSCC) tissues and to examine the clinicopathological correlation between protein levels and LSCC. RT-PCR and Western blot were used to examine the expression of ZEB1 and E-cadherin mRNAs and proteins in LSCC tissues as well as in adjacent normal tissues, and then analyze the relationship between the clinicopathological characteristics and the expression changes of ZEB1 and E-cadherin mRNAs in LSCC. In addition, RNAi was used to knockdown the expression of the ZEB1 gene in Human HCC827 cells; subsequently, changes in the invasive ability of the resultant cells were studied. The positive rates of ZEB1 and E-cadherin mRNAs in LSCC tissues were 69.2 and 38.5 %, respectively. They differed significantly from the corresponding positive rates in the adjacent normal lung tissues (15.4 and 80.8 %, p < 0.05). There was a negative correlation between the protein levels of ZEB1 and E-cadherin in LSCC tissues (r = -0.714, p < 0.001); in addition, it was found that ZEB1 protein expression in LSCC tissues was significantly higher than that in the neighboring normal lung tissues (p < 0.05), and its expression was also significantly higher in patients with lymph node metastases and distant metastases compared to those patients without metastatic disease (p < 0.05). On the contrary, E-cadherin expression was significantly lower in LSCC tissues than that in the neighboring normal tissue (p < 0.05). It was lower in patients with lymph node metastasis and distant metastasis compared to patients without metastatic disease (p < 0.05). However, the expression of ZEB1 and E-cadherin was independent of gender, age, tumor size, or tumor differentiation level (p > 0.05). Transfection of ZEB1 siRNA into HCC827 cells significantly reduced the ZEB1 protein level (p < 0.01) and significantly elevated E-cadherin levels (p < 0.01). Moreover, significantly less ZEB1 siRNA-transfected cells migrated through Transwell chambers in the LSCC tissue than that in the control groups (untransfected or transfected with control siRNA, p < 0.01). The expression of the ZEB1 gene in LSCC tissues is downregulated with the expression of E-cadherin. On the other hand, the expression of siRNA against ZEB1 promotes E-cadherin expression and suppresses the invasive ability conferred by E-cadherin. In conclusion, our data suggested that overexpression of the ZEB1 gene is possibly associated with the occurrence, development, invasion of LSCC. 相似文献