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苏北盆地油源判别指标研究   总被引:2,自引:2,他引:0       下载免费PDF全文
苏北盆地有上白垩统泰州组二段、古新统阜宁组二段、四段3套油源,母岩干酪根性质和地质环境十分接近,通过一般的地球化学指标很难彻底区分它们,为此因地制宜采用了多参数联合图版以及正烷烃分布、原生甾烷分布、三芳甾系列、二甲基咔唑系列等指标,使3套油源达到有效区分。值得提出的是,用于运移研究的二甲基咔唑系列分布在同源油之间也表现出惊人的稳定性,并且提供出进一步细分油源的指纹信息。   相似文献   
3.
林宝元  王育生 《核技术》1993,16(5):283-285
对37名骨密度(BD)低下的飞行员(实验组)和BD正常的48名飞行员、100名地面人员(正常对照组)进行了BD和血清TT_3、TT_4、TSH IRMA、CT、PTH、E_2和T放射免疫测定。结果显示,实验组BD均值明显低于对照组(p<0.01),血清TT_3、TT_4、CT、E_2(女性)和T(男性)均值与对照组比较,大多数年龄存在着显著或非常显著差异(p<0.05或p<0.01)。同时对飞行人员BD与几种内分泌激素关系进行了探讨。  相似文献   
4.
Hormone signaling plays a pivotal role in plant–microbe interactions. There are three major phytohormones in plant defense: salicylic acid (SA), jasmonic acid (JA), and ethylene (ET). The activation and trade-off of signaling between these three hormones likely determines the strength of plant defense in response to pathogens. Here, we describe the allocation of hormonal signaling in Brassica napus against the fungal pathogen Leptosphaeria maculans. Three B. napus genotypes (Westar, Surpass400, and 01-23-2-1) were inoculated with two L. maculans isolates (H75 8-1 and H77 7-2), subsequently exhibiting three levels of resistance: susceptible, intermediate, and resistant. Quantitative analyses suggest that the early activation of some SA-responsive genes, including WRKY70 and NPR1, contribute to an effective defense against L. maculans. The co-expression among factors responding to SA/ET/JA was also observed in the late stage of infection. The results of conjugated SA measurement also support that early SA activation plays a crucial role in durable resistance. Our results demonstrate the relationship between the onset patterns of certain hormone regulators and the effectiveness of the defense of B. napus against L. maculans.  相似文献   
5.
Hormone receptor expression patterns often correlate with infiltration of specific lymphocytes in tumors. Specifically, the presence of specific tumor-infiltrating lymphocytes (TILs) with particular hormone receptor expression is reportedly associated with breast cancer, however, this has not been revealed in epithelial ovarian cancer (EOC). Therefore, we investigated the association between hormone receptor expression and TILs in EOC. Here we found that ERα, AR, and GR expression increased in EOC, while PR was significantly reduced and ERβ expression showed a reduced trend compared to normal epithelium. Cluster analysis indicated poor disease-free survival (DFS) in AR+/GR+/PR+ subgroup (triple dominant group); while the Cox proportional-hazards model highlighted the triple dominant group as an independent prognostic factor for DFS. In addition, significant upregulation of FoxP3+ TILs, PD-1, and PD-L1 was observed in the triple dominant group compared to other groups. NanoString analyses further suggested that tumor necrosis factor (TNF) and/or NF-κB signaling pathways were activated with significant upregulation of RELA, MAP3K5, TNFAIP3, BCL2L1, RIPK1, TRAF2, PARP1, and AKT1 in the triple dominant EOC group. The triple dominant subgroup correlates with poor prognosis in EOC. Moreover, the TNF and/or NF-κB signaling pathways may be responsible for hormone-mediated inhibition of the immune microenvironment.  相似文献   
6.
CYP154C5 from Nocardia farcinica is a P450 monooxygenase able to hydroxylate a range of steroids with high regio- and stereoselectivity at the 16α-position. Using protein engineering and substrate modifications based on the crystal structure of CYP154C5, an altered regioselectivity of the enzyme in steroid hydroxylation had been achieved. Thus, conversion of progesterone by mutant CYP154C5 F92A resulted in formation of the corresponding 21-hydroxylated product 11-deoxycorticosterone in addition to 16α-hydroxylation. Using MD simulation, this altered regioselectivity appeared to result from an alternative binding mode of the steroid in the active site of mutant F92A. MD simulation further suggested that the entrance of water to the active site caused higher uncoupling in this mutant. Moreover, exclusive 15α-hydroxylation was observed for wild-type CYP154C5 in the conversion of 5α-androstan-3-one, lacking an oxy-functional group at C17. Overall, our data give valuable insight into the structure–function relationship of this cytochrome P450 monooxygenase for steroid hydroxylation.  相似文献   
7.
聚乙二醇化重组人生长激素的性质及活性   总被引:1,自引:0,他引:1  
目的 研究聚乙二醇化重组人生长激素的性质及活性。方法 通过分子筛高效液相 (SizeexclusionHPLC)、毛细管等电聚焦 (CIEF)、圆二色谱 (CD)以及荧光光谱等方法检测单聚PEG- GH的纯度、等电点、二级结构以及分子构象 ;采用妊娠兔肝细胞放射受体分析法 (RRA)检测单聚PEG GH的体外受体亲和力 ,采用未成年去垂体大鼠体重增加法检测体内生物活性。结果 分子筛高效液相图谱上仅出现一个峰 ,表明样品纯度很高 ,等电点范围为 5 .1~ 5 .2 ,与未修饰的rhGH的等电点相一致 ;CD谱与荧光光谱均表明单个mPEG ALD的修饰对rhGH的二级结构以及分子构象没有明显影响 ;与未修饰的rhGH相比 ,单聚PEG GH体外受体亲和力明显降低 ;但体内作用时间更长 ,且更加有效。结论 此结果为进一步研究和开发长效重组人生长激素提供了理论依据。  相似文献   
8.
The aggregation pheromone of the German cockroach,Blattella germanica, consists of attractant and arrestant, which can be detected by olfactometer and choice-chamber assay, respectively. Both were extracted from the frass-contaminated filter paper being used as a shelter. They were separated by solvent partition withn-butanol and water. The arrestant from then-butanol phase was purified by open column chromatography and then successive HPLC isolated two major arrestant components. Spectral evidence from SI-MS, HR-EI-MS, and NMR experiments with pulse techniques provided possible structures as 1-(6-chloro-4,5-epoxy-5-stigmast-3-yl)--d-glucopyranoside and 1-(6-chloro-5-hydroxy-5-stigmast-3-yl)--d-glu-copyranoside, denoted as blattellastanoside-A and blattellastanoside-B, respectively. They represented arrestant activity as median effective doses (ED50) at 0.044 (A) and 3.2 (B) nmol on 1.0 cm2 of Whatman No. 1 filter paper.  相似文献   
9.
针对网络故障诊断中的模式识别问题, 提出一种基于多重提升(MultiBoost) 的优化支持向量机集成学习方法. 首先, 利用自适应的荷尔蒙调节遗传算法(HMGA), 对支持向量机基分类器进行建模参数优化; 然后, 通过构建MultiBoost 集成学习方法将多个基分类器集成, 建立以多分类器优化集成为核心的故障诊断系统. 实验结果表明, 所提出的方法在网络故障诊断中, 迭代次数少、建模时间短, 并且能够明显提高故障分类的准确率.  相似文献   
10.
为了解决多机器人系统分布式控制问题,借鉴人体内分泌系统研究的理论成果,提出基于晶格的人工内分泌系统模型.该模型以环境晶格化为基础,以细胞智能化为依托,以累加激素为纽带,以靶细胞为导向,能够适应外环境的持续变化,保持内环境的相对稳定,充分体现人体内分泌系统的自组织和自修复特性.实验结果表明,无需复杂的集中控制策略,基于该...  相似文献   
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