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新型冠状病毒肺炎(corona virus disease 2019,COVID-19)自2019年12月爆发以来,由于具有高传染性,迅速在世界各地蔓延,国内外疫情防治形势空前严峻。COVID-19不仅造成肺部、肠道、肾脏等多脏器损害,且部分患者以眼表损害为首发或伴发症状出现,临床上很容易被忽视。COVID-19的眼表损害归属于祖国医学“天行赤眼”范畴,本文结合国内外最新的文献报道,探讨新型冠状病毒(2019 novel corona virus,2019-nCoV)对眼表的损害,阐明其可能机制,并从中西医角度提出可行的治疗措施。  相似文献   
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ABSTRACT

Genotoxic compounds may be detoxified to non-genotoxic metabolites while many pro-carcinogens require metabolic activation to exert their genotoxicity in vivo. Standard genotoxicity assays were developed and utilized for risk assessment for over 40 years. Most of these assays are conducted in metabolically incompetent rodent or human cell lines. Deficient in normal metabolism and relying on exogenous metabolic activation systems, the current in vitro genotoxicity assays often have yielded high false positive rates, which trigger unnecessary and costly in vivo studies. Metabolically active cells such as hepatocytes have been recognized as a promising cell model in predicting genotoxicity of carcinogens in vivo. In recent years, significant advances in tissue culture and biological technologies provided new opportunities for using hepatocytes in genetic toxicology. This review encompasses published studies (both in vitro and in vivo) using hepatocytes for genotoxicity assessment. Findings from both standard and newly developed genotoxicity assays are summarized. Various liver cell models used for genotoxicity assessment are described, including the potential application of advanced liver cell models such as 3D spheroids, organoids, and engineered hepatocytes. An integrated strategy, that includes the use of human-based cells with enhanced biological relevance and throughput, and applying the quantitative analysis of data, may provide an approach for future genotoxicity risk assessment.  相似文献   
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Abstract

Cadmium (Cd) as environmental pollutant can induce severe damage, particularly to the testis. This study investigated the effects of Caffeic acid phenethyl ester (CAPE) on testicular dysfunction induced by Cd. Adult mice were intraperitoneally injected with cadmium chloride (CdCl2) with different doses of CAPE pretreatment. After CdCl2 injection, body/testis weight ratio decreased, Cd levels accumulated and zinc levels decreased in testis. Furthermore, Cd intoxication caused a significant increase of oxidative stress levels, antioxidant enzymes activities, and glutathione levels. Interestingly, significant improvements were observed after the administration of CAPE. Our results demonstrated the protective effect of CAPE, linking Cd testicular dysfunction to oxidative stress.  相似文献   
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Background and Aim:  We recently reported that cyclooxygenase (COX)-2 is upregulated in the rat small intestine after administration of indomethacin, and this may be the key to non-steroidal anti-inflammatory drug (NSAID)-induced intestinal damage. The present study investigated the mechanism for COX-2 expression induced in the rat small intestine by indomethacin, in relation with ulcerogenic processes.
Methods:  Animals were given indomethacin or SC-560 p.o., and the intestinal mucosa was examined 24 h later.
Results:  Indomethacin caused hemorrhagic lesions in the small intestine, accompanied with an increase in intestinal motility, bacterial invasion and inducible nitric oxide synthase (iNOS) activity, as well as the expression of COX-2 mRNA in the mucosa. Although SC-560 did not cause any damage, this agent caused intestinal hypermotility, the bacterial invasion and the upregulation of COX-2 expression. The mucosal PGE2 content was decreased by SC-560 at 3 h but recovered 12 h later, and this recovery of PGE2 was attenuated by both atropine and ampicillin, in addition to rofecoxib. The intestinal hypermotility response to indomethacin was prevented by both 16,16-dimethyl PGE2 and atropine, but not ampicillin. Yet all these agents inhibited not only the bacterial invasion but also the expression of COX-2 and iNOS activity in the intestinal mucosa following indomethacin treatment, resulting in the prevention of intestinal lesions.
Conclusion:  These results suggest that COX-2 expression in the intestinal mucosa following the administration of indomethacin is associated with intestinal hypermotility and bacterial invasion. The intestinal hypermotility caused by COX-1 inhibition may be a key to COX-2 expression after administration of NSAIDs and their intestinal ulcerogenic properties.  相似文献   
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目的:讨论萘对人体的慢性毒效应和亚临床客观检测指标。方法:对河南省萘暴露工人(环境接触萘浓度平均为8.25~26.43mg/m3)进行了健康监护和医学动态观察。结果:发现长期萘暴露工人的白细胞、血小板减少及眼晶体混浊检出率显著高于对照组(P<0.001);血清SOD同功酶、GSH-PX活性显著低于对照组,而LPO水平、神经元特异性烯醇化酶(NSE)活性水平以及外周血染色体畸变和微核阳性检出率均显著高于对照组(P<0.001)。神经行为功能检查结果,主要为消极情绪增加,记忆力下降等。事件相关电位P300峰潜伏期比对照组显著延长,与对照组差异显著(P<0.05)。结论:慢性低浓度萘暴露对工人主要损害部位(靶器官)有皮肤,眼、血液和神经组织等。NCTB、NSE、P300三项可作为早期神经受损的客观指标。  相似文献   
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74例小儿慢性头痛经辨证治疗,显效80.95%,好转16.67%,无效2.38%。痰浊头痛二陈汤或半夏白术天麻汤加减;肾虚头痛,杞菊地黄汤加减;淤血头痛,补阳还五汤;气血虚头痛八珍汤加减。指出了小儿内伤头痛的病因病机,并指出脑电图,脑阻抗血流图、CT、甲皱微循环可做为此病的诊断及疗效指标。  相似文献   
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