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Melatonin suppresses TPA‐induced metastasis by downregulating matrix metalloproteinase‐9 expression through JNK/SP‐1 signaling in nasopharyngeal carcinoma 下载免费PDF全文
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Mengyan Nie Julian A. Wharton Andy Cranny Nick R. Harris Robert J.K. Wood Keith R. Stokes 《Materials》2013,6(10):4345-4360
The ability to predict structural degradation in-service is often limited by a lack of understanding of the evolving chemical species occurring within a range of different microenvironments associated with corrosion sites. Capillary electrophoresis (CE) is capable of analysing nanolitre solution volumes with widely disparate concentrations of ionic species, thereby producing accurate and reliable results for the analysis of the chemical compositions found within microenvironment corrosion solutions, such as those found at crevice and pit corrosion sites. In this study, CE with contactless conductivity detection (CCD) has been used to characterize pitting and crevice corrosion solution chemistries for the first time. By using the capillary electrophoresis with contactless conductivity detection (CE-CCD) system, direct and simultaneous detection of seven metal cations (Cu2+, Ni2+, Fe3+, Fe2+, Cr3+, Mn2+, and Al3+) and chloride anions was achieved with a buffer solution of 10 mM 2,6-pyridinedicarboxylic acid and 0.5 mM cetyltrimethylammonium hydroxide at pH 4 using a pre-column complexation method. The detection limits obtained for the metal cations and chloride anions were 100 and 10 ppb, respectively. The CE-CCD methodology has been demonstrated to be a versatile technique capable of speciation and quantifying the ionic species generated within artificial pit (a pencil electrode) and crevice corrosion geometries for carbon steels and nickel-aluminium bronze, thus allowing the evolution of the solution chemistry to be assessed with time and the identification of the key corrosion analyte targets for structural health monitoring. 相似文献
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Objectives To evaluate an intervention aimed at increasing the quantity and quality of brief opportunistic general practitioner (GP) advice to smokers encouraging and supporting quit attempts. Design Randomized controlled trial with two groups: (1) control and (2) GP desktop resource (GDR). Smoking cessation activities of GPs were assessed by an independent postal survey 1 month after distribution of resource. Subjects and setting One hundred and seven GPs in West Dorset. Main outcome measures GPs’ self‐reported rates of advising and counselling smokers on cessation over the previous week. Results The rate of opportunistic advice per week in the GDR group was 4.9 (SD = 4.1), compared with 2.8 (SD = 1.8) in the control group, F = 8.2, p = 0.0025, one‐tailed. The rate of giving counselling was also higher 2.2 (SD = 3.2) in the intervention group versus 1.0 (SD = 1.4) in the control group, F = 4.0, p = 0.025, one‐tailed. The proportion who had recommended or prescribed NRT was greater, although not significantly (54% versus 46%, Fisher’s exact p = 0.1, one‐tailed). Conclusions The findings indicate that the GDR can increase the rate of delivery of opportunistic advice and provision of counselling. Given the importance of this activity, a larger trial appears to be warranted to examine the long‐term effect and the effect on cessation rates in patients. 相似文献
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Rong-Nan Chien MD Professor Yun-Fan Liaw MD Professor 《Best Practice & Research: Clinical Gastroenterology》2008,22(6):1081-1092
Nucleoside and nucleotide analogues are potent HBV suppressors, but these agents rarely eradicate HBV. Therefore, the durability of viral response is a problem, and long-term therapy is usually required to ensure maintained HBV suppression. Studies have shown that long-term therapy starting with lamivudine may significantly improve survival, reduce the risk of liver-related major complications, and prevent the development of cirrhosis and HCC in chronic hepatitis B patients. However, drug resistance is a critical challenge during long-term nucleos(t)ide analogue maintenance therapy. The emergence of these mutants is characterized by an increasing level of serum HBV DNA, elevation of ALT level, and even hepatitis flare or decompensation. The prevention and proper management of drug resistance are crucial to ensure long-term success. To start treatment in the right patients at the right time with the right drug is essential in minimizing the problem of drug resistance. Each of these agents has a different profile of resistant mutations. In choosing a direct antiviral agent to initiate therapy, resistance profile is a crucial factor to consider, apart from potency and cost. In the case of drug resistance emerging, timely institution of a drug without cross-resistance may rescue the adverse effects of drug resistance and ensure the long-term success of nucleos(t)ide analogue therapy. To develop strategies for enhancing the therapeutic response and shortening the duration of therapy is an ultimate goal to avoid the problems of drug resistance.68
- • nucleos(t)ide analogues for hepatitis B virus (HBV) are highly effective in suppressing HBV replication but rarely eliminate the virus
- • long-term therapy is usually required
- • emergence of drug-resistant HBV mutations is a critical challenge
- • to treat the right patient at the right time with the drug with highest genetic barrier to drug resistance is essential to minimize the problem with drug resistance
- • the strategy of on-treatment adjustment based on level of suppression of HBV DNA needs to be clarified
- • studies are needed to find the optimal combination therapy for both better therapeutic efficacy and less drug resistance
- • oral antiviral agents able to attack cccDNA are urgently needed
120.
Beaglehole R Epping-Jordan J Patel V Chopra M Ebrahim S Kidd M Haines A 《Lancet》2008,372(9642):940-949
The burden of chronic diseases, such as heart disease, cancer, diabetes, and mental disorders is high in low-income and middle-income countries and is predicted to increase with the ageing of populations, urbanisation, and globalisation of risk factors. Furthermore, HIV/AIDS is increasingly becoming a chronic disorder. An integrated approach to the management of chronic diseases, irrespective of cause, is needed in primary health care. Management of chronic diseases is fundamentally different from acute care, relying on several features: opportunistic case finding for assessment of risk factors, detection of early disease, and identification of high risk status; a combination of pharmacological and psychosocial interventions, often in a stepped-care fashion; and long-term follow-up with regular monitoring and promotion of adherence to treatment. To meet the challenge of chronic diseases, primary health care will have to be strengthened substantially. In the many countries with shortages of primary-care doctors, non-physician clinicians will have a leading role in preventing and managing chronic diseases, and these personnel need appropriate training and continuous quality assurance mechanisms. More evidence is needed about the cost-effectiveness of prevention and treatment strategies in primary health care. Research on scaling-up should be embedded in large-scale delivery programmes for chronic diseases with a strong emphasis on assessment. 相似文献