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1.
BackgroundAmomum villosum Lour., (Zingiberaceae) an herbaceous plant in the ginger family, has been used to treat various diseases. In a single-blind, randomized, crossover study, we assessed the postprandial blood insulin and blood glucose responses in healthy subjects (n = 40) after the Amomum villosum water extract (AVE) (5 g/person) or a placebo (5 g/person) consumption.MethodsDuring each treatment course, the healthy subject consumed a regular late afternoon meal, followed by fasting for 12 h, and arrived at the clinical study center the next morning. Blood insulin and blood glucose levels were assessed at 0, 30, 60, 90, and 120 min after AVE consumption. Between each treatment, the subjects accomplished one week of a washout period.ResultsThe AVE intake demonstrated a significant (67.26%) decline in postprandial blood glucose AUC0–120 min (incremental area under the curve from 0 to 120 min) versus the placebo (P = 0.011). Furthermore, AVE reduced postprandial blood insulin AUC0–120 min by 59.95% compared to the placebo group (P < 0.003), supporting the blood glucose results.ConclusionThis study revealed that AVE consumption significantly reduced postprandial insulin and glucose levels in healthy individuals, due in part to inhibition of α-glucosidase, and glucose transport.  相似文献   
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The direct interaction of drugs with the cell membrane is often neglected when drug effects are studied. Systematic investigations are hindered by the complexity of the natural membrane and model membrane systems can offer a useful alternative. Here some examples are reviewed of how model membrane architectures including vesicles, Langmuir monolayers and solid supported membranes can be used to investigate the effects of drug molecules on the membrane structure, and how these interactions can translate into effects on embedded membrane proteins.  相似文献   
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A brief review is provided in some advances in understanding the ecology of pike Esox lucius Linnaeus over the last 10 years. Based on long-term studies and manipulative, often short-term experiments (laboratory, field and mesocosms) several established theories have been supported, as well as new concepts developed. Despite their wide distribution pike show low levels of polymorphism and divergence indicative of a recent common ancestral population. Recent genetic studies, however, indicate a single refugium in North America compared to several refugia in Europe. Pike are found in rivers, lakes and weakly saline waters. Variables such as growth and mortality are mainly affected by factors such as temperature, water transparency, productivity, availability of prey and density of pike and other predators. In choice of habitat pike have been shown to support the ideal free-distribution theory. The importance of macrophyte habitat in the life history of pike has been reconfirmed and pike have been shown to be flexible in response to water clarity. Pike are extremely ‘plastic’ in choice of prey types, prey size and in response to prey behaviour (e.g. they are unaffected by shoal size). Predation by pike not only affects abundance and biomass of prey (including younger and smaller pike through cannibalism which plays a major role in population dynamics, other fishes and invertebrates) but also evolution and adaptation of their morphology (in particular body shape) and behaviours. There appears to be no relationship between stock and recruitment. Recruitment is influenced by several abiotic factors in lakes and rivers. Pike play a major role in structuring freshwater communities and have been used in stocking programmes to improve water quality (biomanipulation). Many new concepts have been developed in pike behaviour in maximizing these stocking programmes both in biomanipulation and fisheries management. Despite many recent advances in understanding the ecology of pike, particularly at the individual level, developments in quantifying and modelling the role of pike as a top predator in large ecosystems have been limited, probably due to the difficulties of sampling natural populations. Guest editors: J. M. Farrell, C. Skov, M. Mingelbier, T. Margenau & J. E. Cooper International Pike Symposium: Merging Knowledge of Ecology, Biology, and Management for a Circumpolar Species  相似文献   
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Allergic rhinitis is a chronic inflammatory disease that is assumed to be due to an interaction between different genetic and/or environmental factors. A disintegrin and metalloprotease domain 33 (ADAM33) has been extensively studied as a susceptibility gene in asthma and has been linked to bronchial hyper-responsiveness. In this study, we investigated the association between ADAM33 single nucleotide polymorphisms and the incidence of allergic rhinitis among the Jordanian population. We conducted a case–control association study on 120 adult individuals diagnosed with allergic rhinitis and 128 normal healthy controls. 8 single-nucleotide polymorphisms in ADAM33 were genotyped using PCR-RFLP method. No significant differences in the allelic frequencies of all SNPs tested between AR patients and the control volunteers were found, although S2 C/G SNP showed a tendency toward significance with P = 0.06. On the genotype level significant association were found in the following genotypes: T1 AA, T1 AG, T2 GG, T2 AG, T + 1 GG, T + 1 AG, V4 CG, S2 CC, S2 CG, Q-1AA. Seven haplotypes were present only within AR patients and eight haplotypes were completely absent from the AR patients. Three haplotypes exhibited significant association with AR P ≤ 0.05, two of them were present only in AR patients. In conclusion, the polymorphisms in the ADAM33 gene are associated with susceptibility to AR in the Jordanian population. Furthermore, the haplotype of the tested SNPs were also associated with the risk of AR.  相似文献   
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According Global Cancer Statistics 2020 GLOBOCAN estimates female breast cancer was found as the most commonly diagnosed cancer, with an estimated 2.3 million new cases (11.7%), and the fourth leading cause (6.9%) of cancer death among women worldwide. Identification of new diagnostic marker sharply characterize the tumor feature is intensive need. The present work was performed to investigate the involvement of the INF-γ + 874 T/A gene polymorphism in different breast cancer prognostic factors. Polymorphism detection analysis was performed on 163 subjects from breast cancer patients, 79 with inflamed cells of breast patients and 144 controls. The gene polymorphism was detected using the amplification refractory mutation system- polymerase chain reaction method (ARMS-PCR). The distribution of INF-γ T + 874A gene polymorphism shows strong significant association between INF-γ + 874 T/A genotypes TT in BC patients (ORTT: 6.41 [95% CI = 2.72–15.1] P < 0.0001) as well as strong significant association regarding T allele (ORT: 1.99 [95% CI = 1.43–2.76] P < 0.0001) when compared to the healthy control. In ICB group the strong association was noted with INF-γ + 874 T/A genotypes AT genotype (ORAT: 2.28 [95% CI = 1.22–4.29] P = 0.007). From the different histological BC hormonal markers the human epidermal growth factor receptor 2 (HER2) was showing significant association in INF-γ + 874 T/A genotypes TT (P = 0.03) and recessive model (TT versus AA + AT P = 0.03). Concerning different BC prognostic models, the poor prognostic one of luminal B, (ER+ve PR+ve Her2+ve) show significant association in the host INF-γ + 874 T/A genotype (TT, P = 0.03) and recessive model (TT versus AA + AT P = 0.02) when compared to the good prognostic hormonal status luminal A model, (ER+ve PR+ve Her2-ve). It seems that this is the first study that interested in correlate the INF-γ + 874 T/A gene polymorphisms in Egyptian BC patients. T allele, TT genotype and recessive model of the INF-γ + 874 T/A gene variants were documented as risk factors for BC pathogenesis. It may be used as practical biomarker to guide the BC carcinogenesis and risk process.  相似文献   
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Falls in the hospital setting are a major health problem due to their high prevalence and their physical, functional, psychological or economic consequences. Since 1990s, different fall risk assessment scales have been developed to detect high-risk patients, which are also applied in the hospital setting. The aim of this review is to analyse the validity of different scales for assessing fall risk in adults in the hospital setting, especially in elderly patients. Following a literature search in April 2021, 36 primary studies were found that analysed the validity of the Downton, Morse, Hendrich II, Stratify and Tinetti scales. Meta-analyses of sensitivity and specificity showed a high heterogeneity that does not allow recommending a specific tool that can be considered as standard in acute inpatients.  相似文献   
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恶性胶质瘤年发病率约为5/100,000。美国每年有超过14,000例的新发恶性脑胶质瘤患者。治疗主要以手术治疗为主,手术肿瘤的切除程度影响患者的预后。外科手术治疗脑肿瘤需要精确定位脑肿瘤组织在正常脑组织中的位置以便能够获得精确的组织活检和肿瘤的完全切除。量子点是稳定存在的,产生荧光的可视化半导体纳米晶体。静脉注射量子点伴随着网状内皮系统和巨噬细胞的隔离。巨噬细胞可渗入到肿瘤组织并且能够吞噬通过静脉注射的光量子来产生可视化的肿瘤标记。通过巨噬细胞介导,将光量子运输至肿瘤组织展现了一种新兴技术来标记术前肿瘤组织。由于肿瘤组织中的光量子可以被光学成像和光谱学工具来探测,因此在脑肿瘤组织活检和切除中可以为外科医生提供可视化得实时反馈。  相似文献   
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LAMP-LFD技术及其在生物快检方面应用   总被引:1,自引:0,他引:1  
LAMP-LFD技术是环介导横温扩增技术(Loop-mediated isothermal amplification)与横向流动试纸条(Lateral flow dipstick)相结合的一种新颖的检测技术,该技术将核酸横温扩增和可视化试纸条检测有机地结合。环介导等温扩增技术(LAMP),只需要在恒温(60℃~65℃)条件下保温几十分钟,即可将所需目的基因扩增到109水平。横向流动试纸条(LFD),融合了免疫层析技术和分子生物学手段,能在纸条上形成有颜色的检测线从而可以特异性地检测出该目标产物。环介导横温扩增技术(LAMP)与横向流动试纸条(LFD)相互结合的技术,使LAMP扩增产物现场检测可视化,检测结果明显直观,通过肉眼即可辨认,并具有高特异性、高灵敏度、简便、安全及成本低的特点,一度引起科研工作者的广泛关注。综述了环介导横温扩增方法与横向流动试纸条相结合(LAMP-LFD)技术的原理、优势、及其在生物快速检测方面的应用等,并指出了LAMP-LFD技术目前存在的不足以及展望。  相似文献   
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