Let G be a finite group. A subgroup H of G is said to be an ℋ c -subgroup of G if there exists a normal subgroup T of G such that G = H T and H g ∩ N T ( H ) ≤ H for all g ∈ G . We say that H is weakly ℋ c -embedde...
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Let G be a finite group. A subgroup H of G is said to be an ℋ c -subgroup of G if there exists a normal subgroup T of G such that G = H T and H g ∩ N T ( H ) ≤ H for all g ∈ G . We say that H is weakly ℋ c -embedded in G if there exists a normal subgroup T of G such that H G = H T and H g ∩ N T ( H ) ≤ H for all g ∈ G . In this paper, we investigate the structure of the finite group G under the assumption that some subgroups of prime power order are weakly ℋ c -embedded in G . Our results improve and generalize several recent results in the literature.
The assessment of the fibrotic evolution of chronic hepatitis has always been a challenge for the clinical hepatologist. Over the past decade, various noninvasive methods have been proposed to detect the presence of f...
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The assessment of the fibrotic evolution of chronic hepatitis has always been a challenge for the clinical hepatologist. Over the past decade, various noninvasive methods have been proposed to detect the presence of fibrosis, including the elastometric measure of stiffness, panels of clinical and biochemical parameters, and combinations of both methods. The aim of this review is to analyse the most recent data on non-invasive techniques for the evaluation of hepatic fibrosis with particular attention to costeffectiveness. We searched for relevant studies published in English using the Pub Med database from 2009 to the present. A large number of studies have suggested that elastography and serum markers are useful techniques for diagnosing severe fibrosis and cirrhosis and for excluding significant fibrosis in hepatitis c virus patients. In addition, hepatic stiffness may also help to prognosticate treatment response to antiviral therapy. It has also been shown that magnetic resonance elastography has a high accuracy for staging and differentiating liver fibrosis. Finally, studies have shown that non-invasive methods are becoming increasingly precise in either positively identifying or excluding liver fibrosis, thus reducing the need for liver biopsy. However, both serum markers and transient elastography still have "grey area" values of lower accuracy. In this case, liver biopsy is still required to properly assess liver fibrosis. Recently, the guidelines produced by the World Health Organization have suggested that the AST-to-platelet ratio index or FIB-4 test could be utilised for the evaluation of liver fibrosis rather than other, more expensive non-invasive tests, such as elastography or Fibro Test.
目的探讨细胞外信号调节激酶/c AMP反应元件结合蛋白(ERK/cREB)信号通路在异菝葜皂苷元(SMI)促进β-淀粉样肽(Aβ)损伤SH-SY5Y细胞脑源性神经营养因子(BDNF)表达中的作用及其机制。方法建立Aβ损伤SH-SY5Y细胞模型,采用RT-PcR法检测BDNF m RNA的表达,用Western blotting的方法检测p cREB和p ERK的变化,最后通过阻断实验确认ERK/cREB信号通路在SMI促进BDNF m RNA表达中的作用。结果 SMI能促进Aβ损伤SH-SY5Y细胞BDNF m RNA的表达(P=0.000),并能上调信号分子cREB和ERK1/2的磷酸化水平(P=0.001,P=0.000)。用RNA干扰的方法阻断cREB的表达后,SMI促进BDNF m RNA表达的作用完全消失;用U0126阻断ERK1/2磷酸化后,SMI促进p cREB水平升高的作用完全消失。结论 SMI通过ERK/cREB通路促进Aβ损伤SH-SY5Y细胞BDNF m RNA的表达。
Fly ash particles are usually spherical and based on their chemical composition;they are categorized into two classes: c and F. This study compares the microstructural, mechanical and thermal properties of extruded ri...
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Fly ash particles are usually spherical and based on their chemical composition;they are categorized into two classes: c and F. This study compares the microstructural, mechanical and thermal properties of extruded rigid PVc foam composites reinforced with class c and class F fly ash. The mechanical properties: such as tensile and flexural strength of composites containing class c fly ash were superior to the composites containing class F fly ash particles. composites containing 6 phr class c fly ash showed a 24% improvement in the tensile strength in comparison to a mere 0.5% increase in composites reinforced with class F fly ash. Similarly, the addition of 6 phr of class F fly ash to the PVc foam matrix resulted in a 5.74% decrease in the flexural strength, while incorporating the same amount of class c fly ash led to a 95% increase in flexural strength. The impact strength of the composites decreased as the amount of either type of fly ash increased in the composites indicating that fly ash particles improve the rigidity of the PVc foam composites. No significant changes were observed in the thermal properties of the composites containing either type of fly ash particles. However, the thermo-mechanical properties measured by DMA indicated a steep increase in the viscoelastic properties of composites reinforced with class c flyash. The microstructural properties studied by Scanning Electron Microscopy (SEM) confirmed that fly ash particles were mechanically interlocked in the PVc matrix with good interfacial interaction with the matrix. However, particle agglomeration and debonding was observed in composites reinforced with higher amounts of fly ash.
chronic inflammation associated with hepatitis c virus(HcV) infection can lead to disabling liver diseases with progression to liver cirrhosis and hepatocellular carcinoma. Despite the recent availability of more effe...
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chronic inflammation associated with hepatitis c virus(HcV) infection can lead to disabling liver diseases with progression to liver cirrhosis and hepatocellular carcinoma. Despite the recent availability of more effective and less toxic therapeutic options, in most parts of the world the standard treatment consists of a weekly injection of pegylated interferon α(IFN-α) together with a daily dose of ribavirin. HcV patients frequently present circulating non-organ-specific autoantibodies demonstrating a variety of staining patterns in the indirect immunofluorescence assay for antinuclear antibodies(ANA). Between 20% to 40% of HcV patients treated with IFN-α and ribavirin develop autoantibodies showing a peculiar ANA pattern characterized as rods and rings(RR) structures. The aim of this article is to review the recent reports regarding RR structures and anti-rods/rings(antiRR) autoantibody production by HcV patients after IFN-α/ribavirin treatment. Anti-RR autoantibodies first appear around the sixth month of treatment and reach a plateau around the twelfth month. After treatment completion, anti-RR titers decrease/disappear in half the patients and remain steady in the other half. Some studies have observed a higher frequency of anti-RR antibodies in relapsers, i.e., patients in which circulating virus reappears after initially successful therapy. The main target of anti-RR autoantibodies in HcV patients is inosine-5'-monophosphate dehydrogenase 2(IMPDH2), the rate-limiting enzyme involved in the guanosine triphosphate biosynthesis pathway. Ribavirin is a direct IMPDH2 inhibitor and is able to induce the formation of RR structures in vitro and in vivo. In conclusion, these observations led to the hypothesis that anti-RR autoantibody production is a human model of immunologic tolerance breakdown that allows us to explore the humoral autoimmune response from the beginning of the putative triggering event: exposure to ribavirin and interferon.
Hepatocellular carcinoma(Hcc) is one of the most common causes of cancer-related death worldwide. chronic infection of hepatitis B virus(HBV) and/or hepatitis c virus(HcV) is a major risk factor in the development of ...
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Hepatocellular carcinoma(Hcc) is one of the most common causes of cancer-related death worldwide. chronic infection of hepatitis B virus(HBV) and/or hepatitis c virus(HcV) is a major risk factor in the development of the Hcc, independently from excessive alcohol abuse and metabolic disease. Since the biology of HBV and HcV is different, their oncogenic effect may go through different mechanisms, direct and/or indirect. Viral hepatitis infection is associated with cellular inflammation, oxidative stress, DNA damage, that may lead to subsequent hepatic injuries such as chronic hepatitis, fibrosis, cirrhosis, and finally Hcc. Direct oncogenic properties of these viruses are related with their genotypiccharacteristics and the ability of viral proteins to interact with host proteins, thus altering the molecular pathways balance of the cells. In addition, the integration of HBV DNA, especially the gene S and X, in a particular site of the host genome can disrupt chromosomal stability and may activate various oncogenic mechanisms, including those in hematopoieticcells. Recently, several studies also had demonstrated that viral hepatitis could trigger the population of hepaticcancer stem cells. This review summarize available pre-clinical and clinical data in literature regarding oncogenic properties of HBV and HcV in the early initiation of Hcc.
In the present study, the alloying element Si is blended with (cr 3 c 2 -35% Nicr) powder and this composite powder is HVOF sprayed on three different Fe-based steels namely SA213-T22, MDN-310 and SUPERFER 800H. Oxida...
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In the present study, the alloying element Si is blended with (cr 3 c 2 -35% Nicr) powder and this composite powder is HVOF sprayed on three different Fe-based steels namely SA213-T22, MDN-310 and SUPERFER 800H. Oxidation studies have been conducted on the coated as well as uncoated specimens at 700 o c in air under cyclicconditions. The weight change method was used to establish the kinetics of oxidation. (cr 3 c 2 -35% Nicr) + 5% Si coated steels showed slow oxidation kinetics and considerably lower weight gains than that of uncoated steels. The superior performance of (cr 3 c 2 -35% Nicr) + 5% Si coatings can be attributed due to the formation of a compact and protective oxide layer consisting of cr 2 O 3 , SiO 2 , Nicr 2 O 4 and Ni 2 (SiO 4 ) phases. The uncoated T22 steel suffered a catastrophic degradation in the form of intense spalling of the scale. The combined technique of X-ray diffraction (XRD), scanning electron microscopy/energy dispersive X-ray analysis (***) and X-ray mapping were used to analyze the oxidized products of coated and bare substrate steels.
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