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目的测定H9N2亚型禽流感病毒A/Chicken/Gansu/2/99(CK/GS/2/99)分离株的基因组序列并与参考毒株进行同源性分析,阐明该毒株的遗传变异及分子特征。方法采集发病鸡泄殖腔样品,经鸡胚尿囊腔接种分离病毒,采用RT-PCR方法对CK/GS/2/99株的8个分节段基因进行扩增,分别将其克隆到pGEM-T easy载体后进行序列测定与同源性分析。结果CK/GS/2/99株PB2、PB1、PA、HA、NP、NA、M、NS基因的开放阅读框分别由2280、2274、2151、1683、1497、1401、759、864个碱基组成,分别编码759、757、716、560、498、466、252/97、231/122个氨基酸残基。该毒株HA上HA1和HA2裂解位点序列为PARSSR↓GLF,具有典型的低致病性禽流感病毒的特征。同源性分析显示,CK/GS/2/99株与1998-2002年间大部分中国大陆分离株遗传关系较近,尤其与CK/NX/4/99和CK/HB/31/00株遗传关系密切。结论CK/GS/2/99与大部分流行于中国内陆的H9N2亚型毒株均来源于共同的祖先毒株CK/BJ/1/94,这为了解中国H9N2亚型禽流感病毒的分子流行病学提供了资料。  相似文献   

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AIM To evaluate whether fish oil(FO) can protect liver injury induced by intestinal ischemia/reperfusion(I/R) via the AMPK/SIRT-1/autophagy pathway.METHODS Ischemia in wistar rats was induced by superior mesenteric artery occlusion for 60 min and reperfusion for 240 min. One milliliter per day of FO emulsion or normal saline was administered by intraperitoneal injection for 5 consecutive days to each animal. Animals were sacrificed at the end of reperfusion. Blood andtissue samples were collected for analyses. AMPK, SIRT-1, and Beclin-1 expression was determined in lipopolysaccharide(LPS)-stimulated HepG2 cells with or without FO emulsion treatment.RESULTS Intestinal I/R induced significant liver morphological changes and increased serum alanine aminotransferase and aspartate aminotransferase levels. Expression of p-AMPK/AMPK, SIRT-1, and autophagy markers was decreased whereas tumor necrosis factor-α(TNF-α) and malonaldehyde(MDA) were increased. FO emulsion blocked the changes of the above indicators effectively. Besides, in LPS-stimulated HepG2 cells, small interfering RNA(siRNA) targeting AMPK impaired the FO induced increase of p-AMPK, SIRT-1, and Beclin-1 and decrease of TNF-α and MDA. SIRT-1 siRNA impaired the increase of SIRT-1 and Beclin-1 and the decrease of TNF-α and MDA.CONCLUSION Our study indicates that FO may protect the liver against intestinal I/R induced injury through the AMPK/SIRT-1/autophagy pathway.  相似文献   

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Recent studies have shown that the energy release capacity of Polytetrafluoroethylene (PTFE)/Al with Si, and CuO, respectively, is higher than that of PTFE/Al. PTFE/Al/Si/CuO reactive materials with four proportions of PTFE/Si were designed by the molding–sintering process to study the influence of different PTFE/Si mass ratios on energy release. A drop hammer was selected for igniting the specimens, and the high-speed camera and spectrometer systems were used to record the energy release process and the flame spectrum, respectively. The ignition height of the reactive material was obtained by fitting the relationship between the flame duration and the drop height. It was found that the ignition height of PTFE/Al/Si/CuO containing 20% PTFE/Si is 48.27 cm, which is the lowest compared to the ignition height of other Si/PTFE ratios of PTFE/Al/Si/CuO; the flame temperature was calculated from the flame spectrum. It was found that flame temperature changes little for the same reactive material at different drop heights. Compared with the flame temperature of PTFE/Al/Si/CuO with four mass ratios, it was found that the flame temperature of PTFE/Al/Si/CuO with 20% PTFE/Si is the highest, which is 2589 K. The results show that PTFE/Al/Si/CuO containing 20% PTFE/Si is easier to be ignited and has a stronger temperature destruction effect.  相似文献   

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目的观察黄连温胆汤对载脂蛋白E(ApoE)-/-小鼠动脉粥样硬化的干预效应,从磷脂酰肌醇3-激酶(PI3K)/蛋白激酶B(Akt)/哺乳动物西罗莫司靶蛋白(mTOR)信号通路探讨其机制。方法采用高脂饲料饲养ApoE-/-小鼠4周构建动脉粥样硬化模型。采用全自动生化分析仪检测小鼠血脂水平;采用苏木精-伊红(HE)染色、油红O染色、Masson染色观察主动脉斑块情况;采用免疫组化法检测小鼠主动脉根部PI3K、Akt、mTOR蛋白表达水平。结果与模型组比较,黄连温胆汤高剂量组总胆固醇(TC)、三酰甘油(TG)、低密度脂蛋白胆固醇(LDL-C)均降低(P<0.05)。HE染色显示:模型组主动脉根部斑块明显,呈易损斑块特征,各给药组斑块有不同程度减轻;油红O和Masson染色显示:与模型组比较,雷帕霉素组、黄连温胆汤高剂量组主动脉根部斑块面积减小,胶原纤维含量升高(P<0.05),易损斑块趋于稳定。蛋白免疫组化结果显示:黄连温胆汤中剂量组、黄连温胆汤高剂量组小鼠主动脉PI3K、Akt、mTOR蛋白表达水平降低(P<0.05)。结论黄连温胆汤具有降脂和抗动脉粥样硬化的作用,其机制可能与抑制PI3K/Akt/mTOR信号通路,诱导巨噬细胞自噬有关。  相似文献   

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In recent years, polytetrafluoroethylene (PTFE)/aluminum (Al) energetic materials with high-energy density have attracted extensive attention and have broad application prospects, but the low-energy release efficiency restricts their application. In this paper, oxide, bismuth trioxide (Bi2O3) or molybdenum trioxide (MoO3) are introduced into PTFE/Al to improve the chemical reaction performance of energetic materials. The pressurization characteristics of PTFE/Al/oxide as pressure generators are compared and analyzed. The experiments show that the significantly optimized quasi-static pressure peak, impulse, and energy release efficiency (0.162 MPa, 10.177 s·kPa, and 0.74) are achieved for PTFE/Al by adding 30 wt.% Bi2O3. On the other hand, the optimal parameter obtained by adding 10% MoO3 is 0.147 MPa, 9.184 s·kPa, and 0.68. Further, the mechanism of enhancing the energy release performance of PTFE/Al through oxide is revealed. The mechanism analysis shows that the shock-induced energy release performance of PTFE/Al energetic material is affected by the intensity of the shock wave and the chemical reaction extent of the material under the corresponding intensity. The oxide to PTFE/Al increases the intensity of the shock wave in the material, but the chemical reaction extent of the material decreases under the corresponding intensity.  相似文献   

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BackgroundRecent studies showed a high frequency of low bone mineral density (BMD) in HIV-infected patients and no reports have been issued in Turkey. Our aim was to evaluate BMD and risk factors for osteopenia/osteoporosis in HIV-infected patients that attended an outpatient clinic in Istanbul, Turkey.MethodIn order to determine the prevalence of BMD, 126 HIV-infected patients had been studied with dual energy X-ray absorptiometry (DEXA). The association between BMD and age, gender, body mass index (BMI), habits, 25(OH)vitamin D, HIV RNA, CD4 lymphocyte nadir, using and duration of highly active antiretroviral treatment (HAART) were investigated by using multivariate analysis.ResultsMedian age was 40.1 years (range, 20–70); 84% were male; 35.7% patients had AIDS, 63.5% were treated with HAART. Osteopenia and osteoporosis were diagnosed in 53.9% and 23.8%, respectively. Mean plasma HIV RNA was 5.2 (SD 1.0) log10 copies/mL and CD4 lymphocyte nadir was 313.8 (SD 226.2)/mm3. Factors associated with bone loss were high viral load (p = 0.034), using (p = 0.033) and duration of HAART (p = 0.008). No correlation had been seen between sex and osteopenia/osteoporosis (p = 0.794). However, males showed higher rates of osteoporosis than females (p = 0.042).ConclusionsOur results show a very high prevalence of bone mass reduction in Turkish HIV-infected patients. This study supports the importance of both HIV and antiretroviral therapy in low BMD.  相似文献   

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This article illuminates the main risks that American Indian/Alaska Native women face for contracting the human immunodeficiency virus, and their challenges in living with HIV disease, by presenting a case study of one Native woman's experiences. The woman, a member of a Midwestern Indian tribe, was a participant in a larger in-depth qualitative longitudinal study of 55 women living with HIV. The findings about her path to healing provide insights for understanding and serving this neglected ethnic population, and her words eloquently articulate the struggles of women of color living in dignity with HIV. The article explores potential venues for reaching Native women with culturally relevant prevention and intervention methods, emphasizing the importance of Native culture and Spirituality.  相似文献   

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血浆三酰甘油水平受基因和环境的双重影响,是脑血管病的重要危险因素之一。人载脂蛋白A1/C3/A4/A5基因簇定位于11号染色体上,对血脂代谢有重要影响。业已证实,APOA1/C3/A4/A5基因簇上的基因突变与血浆三酰甘油水平有关,但研究结果不一。文章将对此基因簇上不同基因多态性位点与血脂代谢及动脉粥样硬化的关系做了综述。  相似文献   

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The erosion phenomenon has a significant influence on many metallic materials used in numerous industrial sectors. In this paper, we present the results of an analysis of the influence of abrasive impact erosion on surface and properties of DC03/1.0347, DC04/1.0338, DC05/1.0312, and DD14/1.0389 deep drawing steels. The chemical composition, static tensile tests, hardness tests, drawability tests, erosion tests, microstructure analysis, surface roughness, and hardness of the plates were investigated. The wear mechanisms and wear behavior of the investigated steels were also discussed. The results obtained in this study allowed the assessment of the microstructural changes in deep drawing steels under the influence of intense erosive impact. The obtained results indicate that the erosive impact may cause a significant grain refinement of the microstructure of the surfaces of the investigated materials. Moreover, large amounts of heat released during erosive impact may cause the material phase changes. This research expands the knowledge on specific mechanisms taking place during sandblasting and their influence on the properties of deep drawing steels and their wear behavior.  相似文献   

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The recent emergence and circulation of the A/ASIA/G-VII (A/G-VII) lineage of foot-and-mouth disease virus (FMDV) in the Middle East has resulted in the development of homologous vaccines to ensure susceptible animals are sufficiently protected against clinical disease. However, a second serotype A lineage called A/ASIA/Iran-05 (A/IRN/05) continues to circulate in the region and it is therefore imperative to ensure vaccine strains used will protect against both lineages. In addition, for FMDV vaccine banks that usually hold a limited number of strains, it is necessary to include strains with a broad antigenic coverage. To assess the cross protective ability of an A/G-VII emergency vaccine (formulated at 43 (95% CI 8–230) PD50/dose as determined during homologous challenge), we performed a heterologous potency test according to the European Pharmacopoeia design using a field isolate from the A/IRN/05 lineage as the challenge virus. The estimated heterologous potency in this study was 2.0 (95% CI 0.4–6.0) PD50/dose, which is below the minimum potency recommended by the World Organisation for Animal Health (OIE). Furthermore, the cross-reactive antibody titres against the heterologous challenge virus were poor (≤log10 0.9), even in those cattle that had received the full dose of vaccine. The geometric mean r1-value was 0.2 (95% CI 0.03–0.8), similar to the potency ratio of 0.04 (95% CI 0.004–0.3). Vaccination decreased viraemia and virus excretion compared to the unvaccinated controls. Our results indicate that this A/G-VII vaccine does not provide sufficient protection against viruses belonging to the A/IRN/05 lineage and therefore the A/G-VII vaccine strain cannot replace the A/IRN/05 vaccine strain but could be considered an additional strain for use in vaccines and antigen banks.  相似文献   

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The crustacean eyestalk CHH/MIH/GIH gene family represents a unique group of neuropeptide originally identified in crustaceans. These neuropeptides shared a high degree of amino acid identity, and the conservation of cysteine residues at the same relative positions. Based on their biological, biochemical, and molecular properties, they can be divided into the CHH and MIH subtypes with two major members in each subtype. In the shrimp, the CHH-subtypes can be divided into two forms (CHH-A and CHH-B). The CHH-A gene also comprises several isoforms which shared a high overall sequence identity. Although the MIH subtypes are postulated to have evolved from the CHH subtypes, the number of major MIH subtypes in each species has yet to be confirmed. While most of the genes consist of the basic plan of three exons and two introns, other alternative spliced variants have recently been described. Moreover, these alternative forms are usually expressed in non-eyestalk tissues. These findings suggest that these neuropeptides may have a broader spectrum of functions in crustaceans. The results from phylogenetic analysis suggest that the evolution of this group of neuropeptides occurs in a manner similar is to the gene duplication and mutation events hypothesized for the origin of the prolactin and growth hormone gene family of the vertebrate pituitary system.  相似文献   

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Background and study aimsHepatitis C virus (HCV) prevalence inchronic kidney disease (CKD) patients is significantly higher than in the general population. This study evaluated the efficacy and safety of combined ombitasvir/paritaprevir/ritonavir-based therapy in HCV patients with renal impairment.Patients and methodsOur study included 829 patients with normal kidney functions (group 1) and 829 patients with CKD (group 2),which were subdivided into patients not requiring dialysis (group 2a) and those on hemodialysis (group2b). Patients received regimens of ombitasvir/paritaprevir/ritonavir with or without ribavirin or sofosbuvir/ombitasvir/paritaprevir/ritonavir with or without ribavirin for 12 weeks. Clinical and laboratory assessment was done before treatment, and patients were followed up for12 weeks after treatment.ResultsThe sustained virological response (SVR) at week 12 was significantly higher in group 1 than in the other three groups/subgroups, being 94.2% vs 90.2%, 90%, and 90.7%, respectively. The regimen with the highest SVR was ombitasvir/paritaprevir/ritonavir with ribavirin. The most common adverse event was anemia, which was more common in group 2.ConclusionOmbitasvir/paritaprevir/ritonavir-based therapy in chronic HCV patients with CKD is highly effective, with minimal side effects despite ribavirin-induced anemia.  相似文献   

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Background and study aimsHepatitis C virus (HCV) prevalence inchronic kidney disease (CKD) patients is significantly higher than in the general population. This study evaluated the efficacy and safety of combined ombitasvir/paritaprevir/ritonavir-based therapy in HCV patients with renal impairment.Patients and methodsOur study included 829 patients with normal kidney functions (group 1) and 829 patients with CKD (group 2),which were subdivided into patients not requiring dialysis (group 2a) and those on hemodialysis (group2b). Patients received regimens of ombitasvir/paritaprevir/ritonavir with or without ribavirin or sofosbuvir/ombitasvir/paritaprevir/ritonavir with or without ribavirin for 12 weeks. Clinical and laboratory assessment was done before treatment, and patients were followed up for12 weeks after treatment.ResultsThe sustained virological response (SVR) at week 12 was significantly higher in group 1 than in the other three groups/subgroups, being 94.2% vs 90.2%, 90%, and 90.7%, respectively. The regimen with the highest SVR was ombitasvir/paritaprevir/ritonavir with ribavirin. The most common adverse event was anemia, which was more common in group 2.ConclusionOmbitasvir/paritaprevir/ritonavir-based therapy in chronic HCV patients with CKD is highly effective, with minimal side effects despite ribavirin-induced anemia.  相似文献   

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目的了解新疆地区HIV感染者/AIDS患者膳食模式、膳食营养素摄人量和相关知识-态度-行为(KAP),为制定科学的膳食模式提供依据。方法采用营养流行病学的方法,设计膳食摄人情况以及相关行为调查表,确定感染者/患者的膳食摄入状况及行为相关情况。结果109例调查对象中以农民和无业者最多,分别占39.4%、33.9%,文化程度小学及以下者占40.4%;膳食结构中豆类及其制品摄人者仅占11.9%,动物性食物者占25.6%,其他畜禽肉、海产品类摄入甚少;除了膳食结构不合理外,患者中吸烟(x^2=39.64)、饮酒(x^2=6.65)分别占43.1%和10.1%,且男女间差异有统计学意义(均P〈0.05);平时体育锻炼者仅占17.4%;体重下降(x^2=6.657)和食欲减退(x^2=18.88)两个指标男女间差异有统计学意义(均P〈0.05)。结论新疆的HIV/AIDS感染者/患者大部分属低文化层次人群,信息来源较为闭塞,营养相关知识掌握甚少;患者中就餐不规律情况较普遍,膳食模式中动物性食物摄入量较少,而导致蛋白质、能量、维生素及矿物质的摄入量不足;感染者/患者的防病意识和自我保健意识淡薄,缺乏卫生保健和营养相关知识;应加强对艾滋病患者营养保健知识的宣传,使广大患者形成有益于健康的行为和生活方式,从而防治疾病,提高生活质量。  相似文献   

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糖尿病肾病(DN)是糖尿病重要的微血管并发症之一,其发病机制是多种因素共同作用的结果.近年来发现Rho/Rho激酶(Rho/ROCK)信号通路与多种组织重构如血管、心肌、肾纤维化等相关.高糖能够刺激肾脏细胞内Rho/ROCK信号通路的激活,后者通过调控转录因子的DNA结合活性上调多种基因的表达,从而引起各种炎性反应及肾小球纤维化,而应用此信号通路选择性抑制剂后可明显改善DN的发生和发展,从而认为Rho/ROCK信号转导通路可能在DN的发病机制中起关键作用.  相似文献   

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