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31.
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
32.
L-丙酰肉碱对再灌注心肌损伤的保护及体外抗自由基作用 总被引:1,自引:0,他引:1
目的:观察L-丙酰肉碱对缺血再灌注心肌的保护作用,并探讨其机理。方法:采用大鼠在体心脏冠状动脉前降支阻断5min造成缺血再灌注模型,持续心电监护,观察心律失常与心功能指标;应用电子顺磁共振观察L-丙酰肉碱对Fenton体系及二甲基亚砜(DMSO)碱性有氧体系产生自由基的作用。结果:L-丙酰肉碱静脉给药明显减少再灌注时室性心动过速、室性纤维颤动的发生(P<0.05),促进再灌注后左室收缩压、左室压最大上升速率、左室压最大下降速率、心力环面积的恢复,与对照组相比,各参数均明显增高(P<0.05);静脉注射L-丙酰肉碱100mmol/L时促进Fenton体系OH的产生,而500mmol/L时产生明显抑制作用,L-丙酰肉碱明显抑制DMSO碱性有氧体系OS的产生。结论:L-丙酰肉碱明显减少再灌注心律失常的发生,促进再灌注后心功能的恢复。推测它对自由基的作用可能是再灌注损伤保护机理之一。 相似文献
33.
Reactive oxygen species and human spermatozoa: physiology and pathology 总被引:20,自引:1,他引:19
The role of reactive oxygen species (ROS) in the pathophysiology of human sperm function has been emphasized in recent years. ROS production in semen has been associated with loss of sperm motility, decreased capacity for sperm–oocyte fusion and loss of fertility. There is a current presumption that the most prolific source of ROS in sperm suspensions is an NADPH oxidase located in leukocytes or in spermatozoa which produces superoxide which is further converted to peroxide by the action of superoxide dismutase. Hydrogen peroxide has been recognized as the most toxic oxidizing species for human spermatozoa, which are very sensitive to lipid peroxidation owing to the high content of polyunsaturated fatty acids in their plasma membrane, though this is not the sole mechanism by which sperm function might be impaired by ROS. Although the excessive production of ROS is detrimental to human spermatozoa, there is a growing body of evidence which suggests that ROS are also involved in the physiological control of some sperm functions. This review focuses on the nature and source of the ROS generated by human spermataozoa as well as their operational mechanisms and their effects, which may be detrimental or beneficial. 相似文献
34.
35.
目的 研究透明质酸钠玻璃体腔内充填对严重开放性眼球损伤预后的影响。方法 在严重开放性眼球损伤一期手术缝合后玻璃体腔内充填透明质酸钠至眼压Tn。结果 用透明质酸钠在玻璃体腔内充填,眼球萎缩的发生率(6.67%)明显低于用BSS液充填的发生率(70.58%)。结论 透明质酸钠玻璃体腔内充填在严重开放性眼球损伤治疗中的应用对眼球外形维持和视功能恢复有重要作用。 相似文献
36.
Rickard Köhnke Andreas Lindqvist Nathanael Göransson Sinan C. Emek Per‐Åke Albertsson Jens F. Rehfeld Anna Hultgårdh‐Nilsson Charlotte Erlanson‐Albertsson 《Phytotherapy research : PTR》2009,23(12):1778-1783
Thylakoids are membranes isolated from plant chloroplasts which have previously been shown to inhibit pancreatic lipase/colipase catalysed hydrolysis of fat in vitro and induce short‐term satiety in vivo. The purpose of the present study was to examine if dietary supplementation of thylakoids could affect food intake and body weight during long‐term feeding in mice. Female apolipoprotein E‐deficient mice were fed a high‐fat diet containing 41% of fat by energy with and without thylakoids for 100 days. Mice fed the thylakoid‐enriched diet had suppressed food intake, body weight gain and body fat compared with the high‐fat fed control mice. Reduced serum glucose, serum triglyceride and serum free fatty acid levels were found in the thylakoid‐treated animals. The satiety hormone cholecystokinin was elevated, suggesting this hormone mediates satiety. Leptin levels were reduced, reflecting a decreased fat mass. There was no sign of desensitization in the animals treated with thylakoids. The results suggest that thylakoids are useful to suppress appetite and body weight gain when supplemented to a high‐fat food during long‐term feeding. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
37.
Summary Cranial computed tomography (CT) of 108 cases with dilated lateral ventricles was reviewed to elucidate the relationship between focal vulnerability of developing brain and disproportional dilatation of lateral ventricles. CT findings of 108 cases with symmetrical dilatation of lateral ventricles were classified into three types by morphometry of lateral ventricles: anterior horn predominant type (31 cases), diffuse type (36 cases), posterior horn predominant type (41 cases). Posterior horn predominant type has a tendency to occur in congenital anomalies and premature brain damage, and anterior horn predominant type in infantile brain damage. This disproportional dilatation of anterior or posterior horns suggests a vulnerability of periventricular structure in developing brain. 相似文献
38.
丹参酚酸B盐对内皮素诱导的人肝星状细胞收缩的抑制作用及机制研究 总被引:1,自引:0,他引:1
目的 以培养的人肝星状细胞(HSC)为研究对象,观察内皮素-1(ET-1)对HSC的收缩作用及丹参酚酸B盐(SA-B)对ET-1的抑制作用,并探讨SA B抑制HSC收缩的作用环节和可能作用机制。 方法 采用酶消化、Nycodenz密度梯度离心的方法分离人HSC,以胶原凝胶收缩法观察ET-1对于传代HSC的收缩作用,以及低、中、高3种剂量的SA B对其不同的干预作用;将ET-1、SA-B直接添加于传代HSC的无血清培养液中,以激光共聚焦显微镜技术观测HSC内钙离子浓度的变化。 结果 胶原凝胶收缩实验显示,ET-1可诱导HSC收缩(P<0.01);3种剂量的SA-B可明显抑制ET-1诱导的HSC收缩(均P<0.01);加入ET-1后,HSC形态学改变明显,细胞数量减少,但SA B对这些改变也有抑制。激光共聚焦显微镜下观察,ET-1可刺激细胞内钙离子短暂迅速增加,加入SA-B后,该作用被明显抑制。 结论 SA-B能显著抑制ET-1诱导的HSC收缩,其抑制收缩的机制与降低HSC内的钙离子浓度有关。SA-B的抑制HSC收缩作用可能是其抗肝纤维化及门脉高压的机制之一。 相似文献
39.
Matteo Tosato Valentina Zamboni Alessandro Ferrini Matteo Cesari 《Clinical Interventions in Aging》2007,2(3):401-412
Aging is commonly defined as the accumulation of diverse deleterious changes occurring in cells and tissues with advancing age that are responsible for the increased risk of disease and death. The major theories of aging are all specific of a particular cause of aging, providing useful and important insights for the understanding of age-related physiological changes. However, a global view of them is needed when debating of a process which is still obscure in some of its aspects. In this context, the search for a single cause of aging has recently been replaced by the view of aging as an extremely complex, multifactorial process. Therefore, the different theories of aging should not be considered as mutually exclusive, but complementary of others in the explanation of some or all the features of the normal aging process. To date, no convincing evidence showing the administration of existing “anti-aging” remedies can slow aging or increase longevity in humans is available. Nevertheless, several studies on animal models have shown that aging rates and life expectancy can be modified. The present review provides an overlook of the most commonly accepted theories of aging, providing current evidence of those interventions aimed at modifying the aging process. 相似文献
40.