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991.
Dimitrios Stagos Gregorios D. Amoutzias Antonios Matakos Argyris Spyrou Aristides M. Tsatsakis Dimitrios Kouretas 《Food and chemical toxicology》2012
Primary liver cancer or hepatocellular carcinoma (HCC) is one of the most frequent tumors representing the fifth commonest malignancy worldwide and the third cause of mortality from cancer. Currently, the treatments for HCC are not so effective and new strategies are needed for its fight. Chemoprevention, the use of natural or synthetic chemical agents to reverse, suppress or prevent carcinogenesis is considered an important way for confronting HCC. Many of the chemopreventive agents are phytochemicals, namely non-nutritive plant chemicals with protective or disease preventive properties. In this review, we focus on plant polyphenols, one of the most important classes of phytochemicals, their chemopreventive properties against HCC and discuss the molecular mechanisms accounting for this activity. 相似文献
992.
The segmented genome of an influenza virus is encapsidated into ribonucleoprotein complexes (RNPs). Unusually among RNA viruses, influenza viruses replicate in the nucleus of an infected cell, and their RNPs must therefore recruit host factors to ensure transport across a number of cellular compartments during the course of an infection. Recent studies have shed new light on many of these processes, including the regulation of nuclear export, genome packaging, mechanisms of virion assembly and viral entry and, in particular, the identification of Rab11 on recycling endosomes as a key mediator of RNP transport and genome assembly. This review uses these recent gains in understanding to describe in detail the journey of an influenza A virus RNP from its synthesis in the nucleus through to its entry into the nucleus of a new host cell. 相似文献
993.
EGFR及NF-κB与鼻咽癌放射敏感性的相关性研究 总被引:1,自引:0,他引:1
目的:通过观察EGFR、NF—κB蛋白表达与鼻咽癌放射敏感性的关系,评价两因子在预测鼻咽癌放射敏感性方面的作用,并为以后靶向基因治疗鼻咽癌、提高放疗效果提供理论依据。方法:采用免疫组织化学SP法检测41例鼻咽癌组织中EGFR及NF-κB的表达情况,并通过随访及临床观察,判断每例患者放疗效果,从而将所有患者分为完全缓解组、部分缓解/稳定组和进展组,评定两因子表达水平与放射敏感性的关系。结果:EGFR、NF-κB在鼻咽癌中均有不同程度表达,两者在鼻咽癌组织的不同放射敏感性中表达各具有差异性(P〈0.05)。完全缓解组与部分缓解/稳定组的EGFR、NF-κB表达均低于进展组(P〈0.05),而完全缓解组与部分缓解/稳定组比较差异无统计学意义(P〉0.05)。两因子表达与鼻咽癌放射敏感性呈负相关。结论:EGFR、NF-κB可能成为预测鼻咽癌放射敏感性的2个重要指标,为鼻咽癌患者的靶向基因治疗提供理论依据。 相似文献
994.
Han-Chen Ho 《Journal of anatomy》2010,216(4):525-532
Extensive morphological modification occurs during mammalian spermiogenesis when spermatids change their spherical shape into cells with a compact head and a long tail. In this study, freeze-fracture was used to elucidate the alteration of the nuclear envelope during this process. Nuclear condensation resulted in a great reduction of spermatid nuclear volume and the formation of the redundant nuclear envelope. During nuclear condensation, distribution patterns of nuclear pores were greatly affected by the developing acrosome and manchette. As the acrosome enlarged to cap the nucleus, the pores redistributed caudally in the nuclear membranes and became exclusively localized to the redundant nuclear envelope. Manchette microtubules play an important role in shaping the nucleus, and formation of the manchette was associated with exclusion of nuclear pores from the underlying nuclear envelope; therefore, it is likely that the redistribution of nuclear pores was aided by manchette development. The appearance of an electron-lucent nuclear region surrounded by the nascent redundant nuclear envelope indicated a pathway for transporting degradation products through the nuclear pores to the residual cytoplasm. The packaging of the nuclear pores into the redundant nuclear envelope suggests that they play a role in late stages of sperm maturation or in fertilization, as most other unnecessary organelles of sperm are discarded during spermiogenesis or during shedding of the cytoplasmic droplet. 相似文献
995.
996.
997.
Brayden Finch Derek G. Gilligan Sean A. Halpin Megan E. Valentine 《Psychiatry, Psychology and Law》2017,24(3):410-427
The prediction and subsequent management of aggression by psychiatric inpatients is a crucial role of the mental health professional. This retrospective cohort study examines the predictive validity of 10 static and dynamic risk-of-violence measures and subscales in 37 forensic and 37 civil inpatients residing in a medium- to-low security psychiatric facility for a period of up to 6 months. Retrospective file records were sourced to conduct an AUC analysis of the ROC curve for short- and medium-term follow-up periods. The hypothesis that dynamic measures would be better predictors than static measures over the short term was supported. Albeit to a lesser extent, dynamic measures were still better predictors than static measures over the medium term. This result was seen in both civil and forensic groups. Three previously untested measures were found to predict aggression within the sample. It is recommended that mental health services employ the use of dynamic measures when making short-term risk-of-violence predictions for civil and/or forensic inpatients. 相似文献
998.
目的 建立使用微量动态浊度法检测细菌内毒素的方法,并进行验证。方法 采用动态浊度法鲎试剂,每孔样品和鲎试剂加样量25 μL,检测波长405 nm,预设OD值0.03,使用半孔酶标板检测,并经过4个实验室协作验证方法的准确度、重现性、线性和范围、耐用性以及重组新型冠状病毒疫苗、重组新型冠状病毒疫苗(5型腺病毒载体)、重组乙型肝炎疫苗、麻腮风联合减毒疫苗、双价肾综合征出血热灭活疫苗、四价流感病毒裂解疫苗共计6种疫苗的品种适用性。结果 高、中、低3个剂量组在4个实验室的共计24次试验总平均回收率分别为100.8%,150.0%,125.3%,RSD值分别为5.3%,11.0%,20.7%;标准曲线在0.01~10 EU·mL-1内相关系数平均值为0.990,耐用度考察2个来源的鲎试剂对检测的影响符合规定;6个品种的共计18批样品的干扰试验回收率均在50%~200%,干扰试验符合规定。结论 建立了使用微量动态浊度法检测细菌内毒素的方法,该方法具有良好的准确度、重现性、线性和范围、耐用性,并且在6种生物制品中具有良好的品种适用性。该方法可用于常规样品的细菌内毒素检测。 相似文献
999.
Skyler G. Jennings Michael G. Heinz Elizabeth A. Strickland 《Journal of the Association for Research in Otolaryngology》2011,12(3):345-360
Masked detection threshold for a short tone in noise improves as the tone’s onset is delayed from the masker’s onset. This
improvement, known as “overshoot,” is maximal at mid-masker levels and is reduced by temporary and permanent cochlear hearing
loss. Computational modeling was used in the present study to evaluate proposed physiological mechanisms of overshoot, including
classic firing rate adaptation and medial olivocochlear (MOC) feedback, for both normal hearing and cochlear hearing loss
conditions. These theories were tested using an established model of the auditory periphery and signal detection theory techniques.
The influence of several analysis variables on predicted tone-pip detection in broadband noise was evaluated, including: auditory
nerve fiber spontaneous-rate (SR) pooling, range of characteristic frequencies, number of synapses per characteristic frequency,
analysis window duration, and detection rule. The results revealed that overshoot similar to perceptual data in terms of both
magnitude and level dependence could be predicted when the effects of MOC efferent feedback were included in the auditory
nerve model. Conversely, simulations without MOC feedback effects never produced overshoot despite the model’s ability to
account for classic firing rate adaptation and dynamic range adaptation in auditory nerve responses. Cochlear hearing loss
was predicted to reduce the size of overshoot only for model versions that included the effects of MOC efferent feedback.
These findings suggest that overshoot in normal and hearing-impaired listeners is mediated by some form of dynamic range adaptation
other than what is observed in the auditory nerve of anesthetized animals. Mechanisms for this adaptation may occur at several
levels along the auditory pathway. Among these mechanisms, the MOC reflex may play a leading role. 相似文献
1000.
Gang Zhou Kun Xia Ge-fei Du Xin-ming Chen Xue-yi Xu Rui Lu Hong-mei Zhou 《Journal of oral pathology & medicine》2009,38(7):559-564
Backgroud: Nuclear factor-kappa B (NF-κB) is believed to be involved in the pathogenesis of various inflammatory diseases, including oral lichen planus (OLP). The objective of the present study was to investigate the possible relationship between NF-κB activation and expression of tumor necrosis factor-alpha (TNF-α) in OLP and their expression pattern in relation to several clinical features.
Methods: Thirty OLP cases were divided into atrophic-erosive form (14 cases) and reticular form (16 cases) according to their clinical manifestations. The expression of NF-κB p65 and TNF-α of both two groups were investigated by immunohistochemical staining, and the percentage of positive cells was calculated in each case. Biopsies of 10 normal oral mucosa (NOM) also underwent the same procedure as controls.
Results: Nuclear factor-kappa B p65 nuclear staining was found in nuclei of basal and suprabasal epithelial keratinocytes in OLP, however, no positive staining was found in NOM. Positive TNF-α staining was detected in cytoplasm of basal epithelial keratinocytes in OLP, and only scattered staining was detected in NOM. Expression of NF-κB p65 and TNF-α were significantly different with respect to clinical forms and lesion sites ( P < 0.05), except for genders ( P > 0.05) in 30 OLP cases. NF-κB nuclear staining positively correlated ( r = 0.676, P < 0.01) with TNF-α overexpression in OLP.
Conclusions: Nuclear factor-kappa B activation and its correlation with overexpression of TNF-α may play an important role in pathogenesis of OLP. There might be a positive regulatory loop between NF-κB and TNF-α, which may contribute to inflammation in OLP; NF-κB may also protect epithelial keratinocytes from excessive apoptosis. 相似文献
Methods: Thirty OLP cases were divided into atrophic-erosive form (14 cases) and reticular form (16 cases) according to their clinical manifestations. The expression of NF-κB p65 and TNF-α of both two groups were investigated by immunohistochemical staining, and the percentage of positive cells was calculated in each case. Biopsies of 10 normal oral mucosa (NOM) also underwent the same procedure as controls.
Results: Nuclear factor-kappa B p65 nuclear staining was found in nuclei of basal and suprabasal epithelial keratinocytes in OLP, however, no positive staining was found in NOM. Positive TNF-α staining was detected in cytoplasm of basal epithelial keratinocytes in OLP, and only scattered staining was detected in NOM. Expression of NF-κB p65 and TNF-α were significantly different with respect to clinical forms and lesion sites ( P < 0.05), except for genders ( P > 0.05) in 30 OLP cases. NF-κB nuclear staining positively correlated ( r = 0.676, P < 0.01) with TNF-α overexpression in OLP.
Conclusions: Nuclear factor-kappa B activation and its correlation with overexpression of TNF-α may play an important role in pathogenesis of OLP. There might be a positive regulatory loop between NF-κB and TNF-α, which may contribute to inflammation in OLP; NF-κB may also protect epithelial keratinocytes from excessive apoptosis. 相似文献