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141.
Bromodomain-containing protein 4 (BRD4) is a new therapeutic target for the treatment of diseases including cardiovascular diseases, cancer, inflammation and central nervous system (CNS) disorders. In this study, we introduced the pharmacophore of fibrates to a BRD4 inhibitor, RVX-208, to design dual-active hypolipidemic compounds, and found that some of new analogues showed favorable hypolipidemic activities. Synthetic accessibility towards this class of compounds optimized RVX-208 as well as would supply more thoughts on hypolipidemic drugs.  相似文献   
142.
目的探讨HPV16E6对细胞中Rap1GAP蛋白水平的影响,为阐明宫颈癌发生发展的分子机制提供实验依据。本研究组前期实验显示,宫颈癌石蜡切片组织中Rap1GAP蛋白水平下降,且与高危型HPV16/18感染相关。本文将进一步探讨HPV16 E6是否导致Rap1GAP蛋白下调的原因。方法通过将HPV16 E6基因插入pGEX-KG的BamHI和Hind Ⅲ酶切位点构建GST标记的HPVE6质粒,采用脂质体转染法将其转染入HeLa细胞中,Westernblot方法观察GST-tagged-HPV16 E6在HeLa细胞中的表达,并观察其对HeLa细胞中内源性Rap1GAP蛋白水平的影响。结果测序表明成功构建GST标记的HPV16E6质粒;Western blot检测表明HPV16E6在HeLa细胞中成功表达;并且发现HeLa细胞中过表达HPV16 E6后,Rap1GAP蛋白相对含量(0.602±0.205)明显低于未转染组(1.130±0.163),差异具有统计学意义(P0.05)。结论HPV16 E6下调Rap1GAP蛋白水平。  相似文献   
143.

Objective

Many studies have addressed the diagnostic performance of echocardiography to evaluate acute cardiac allograft rejection compared with endomyocardial biopsy. But the existence of heterogeneity limited its clinical application. Thus, we conducted a comprehensive, systematic literature review and meta-analysis for the purpose.

Methods

Studies prior to September 1, 2014 identified by Medline/PubMed, EMBASE and Cochrance were examined by two independent reviews. We conducted meta-analysis by using Meta-DiSc 1.4 software. An assessment tool of QUADAS-2 was applied to evaluate the risk of bias and applicability of the studies.

Results

Thirty studies met the inclusion criteria of meta-analysis. The four parameters of pressure half time, isovolumic relaxation time, index of myocardial performance and late diastolic mitral annular motion velocity were included in the meta-analysis, with a pooled diagnostic odds ratio of 10.43, 6.89, 15.95 and 5.68 respectively, and the area under the summary receiver operating characteristic curves value of 0.829, 0.599, 0.871 and 0.685 respectively.

Conclusion

The meta-analysis and systematic review demonstrate that no single parameter of echocardiography showed a reliable diagnostic performance for acute cardiac allograft rejection. A result of echocardiography for ACAR should be comprehensively considered by physicians in the context of clinical presentations and imaging feature.  相似文献   
144.
布氏田鼠摄食量、累积摄食量与日龄的关系   总被引:2,自引:3,他引:2  
布氏田鼠 (Microtusbrandti)是内蒙古典型草原区的主要害鼠 ,其危害方式主要表现之一为与牲畜争夺牧草资源[1,4 ,11,12 ] 。准确地测定其日食量(DFC)与累积摄食量 (CFC) ,对于定量地衡量该鼠的危害程度 ,进一步推算鼠害防治的经济阈值有着重要的意义。一些学者着手有关该鼠食性与食量 ,以及非取食性牧草消耗量的研究工作[3 ,7~ 9] 。但由于受实验手段的限制 ,一直未能解决布氏田鼠日食量、累积摄食量与田鼠年龄的关系等难题。本文以测定典型草原区布氏田鼠日食量与体重的关系 ,结合布氏田鼠体重与年龄的数学关系方程 …  相似文献   
145.
单面针的生物碱研究   总被引:2,自引:2,他引:2  
自芸香科(Rutaceae)花椒属植物单面针(Zanthoxylum nitidum var. fastuosum How ex Huang)的根皮中分得五种已知生物碱:乙氧基白屈菜红碱(ethoxychelerythrine)(Ⅰ);氯化光花椒碱(nitidine chloride)(Ⅱ);去甲基白屈菜红碱(des-N-methychelerythrine)(Ⅲ);α—别隐品碱(α-allocryptopine)(Ⅳ);鹅掌揪宁(liriodenine)(Ⅴ).  相似文献   
146.
147.
Wang  Zhi-Min  Wei  Ai-Li  Zheng  Dan-Man 《Photosynthetica》2001,39(2):239-244
Chlorophyll content, photosystem 2 functioning (Fv/Fm, Fv/F0), activity of ribulose-1,5-bisphosphate carboxylase/oxygenase, and net photosynthetic rates (P N) of flag leaf blade, sheath, peduncle, and ear organs were assessed in large-ear type (Pin 7) and small-ear type (ND93) wheat cultivars. Some differences were found in photosynthetic properties between different green plant parts, the values of all studied parameters in ear parts being higher in Pin7 than in ND93. Furthermore, ear surface areas and ear P N in 26 wheat genotypes measured at anthesis showed highly significant positive correlation with grain mass per ear. Hence a greater capability of ear photosynthesis may result in a greater grain yield in large-ear type cultivars.  相似文献   
148.
Radiation and Environmental Biophysics - Double tracer studies in healthy human volunteers with stable isotopes of cerium citrate were performed with the aim of investigating the gastro-intestinal...  相似文献   
149.
The conformation of native and denaturedPhaseolus coccineus var. rubronanus lectin was studied by circular dichroism (CD) and correlated to the hemagglutinating activity. The far-UV CD spectrum at 25°C showed a broad, negative band around 223 nm and a positive one at 196 nm. CD data analysis of the lectin indicated a -sheet-rich protein. At high temperatures, the spectrum was blue-shifted with increasing magnitude; these changes correlated well with the loss of the activity. The conformation of lectin betweenpH 2 and 10 remained essentially unchanged. AtpH 13 the CD spectrum resembled that of unordered form with a negative band near 200 nm and the activity was completely lost. The denatured lectin in 6 M guanidine hydrochloride would be renatured upon diluting the denaturant to 0.75 M; the changes in CD spectrum again correlated well with the loss of the activity. The effect of sodium dodecyl sulfate on the lectin was drastic; it sharply increased thea-helix at the expense of the -sheet and reduced the activity; the changes reached a plateau above 20 mM surfactant.  相似文献   
150.
Li Y  Tan Z  Li Z  Sun Z  Duan S  Li W 《Bioscience reports》2012,32(3):315-321
xCT is the functional subunit of the cystine/glutamate antiporter system xc-, which exchanges intracellular glutamate with extracellular cystine. xCT has been reported to play roles in the maintenance of intracellular redox and ambient extracellular glutamate, which may affect neuronal function. To assess a potential role of xCT in the mouse hippocampus, we performed fear conditioning and passive avoidance for long-term memories and examined hippocampal synaptic plasticity in wild-type mice and xCT-null mutants, sut mice. Long-term memory was impaired in sut mice. Normal basal synaptic transmission and short-term presynaptic plasticity at hippocampal Schaffer collateral-CA1 synapses were observed in sut mice. However, LTP (long-term potentiation) was significantly reduced in sut mice compared with their wild-type counterparts. Supplementation of extracellular glutamate did not reverse the reduction in LTP. Taken together, our results suggest that xCT plays a role in the modulation of hippocampal long-term plasticity.  相似文献   
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