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1.
乐敏飞 《中国公共卫生管理》2016,(4):477-479
目的调查宁波市北仑区0~14岁儿童哮喘发病率、发病规律及危险因素,为制定防治措施提供参考。方法2013年1月-2014年1月,采用整群抽样法抽取北仑区19所学校0~14岁儿童为调查对象进行问卷调查,对筛查出的疑似哮喘儿童进行确诊,并对其人口学特征进行分析,采用logistic回归方程分析危险因素。结果调查收回有效问卷23 781份,共检出哮喘患儿534例,发病率为2.25%,男女发病率比例为1.92:1。其中发病较轻患儿占44.01%,中度占31.46%,重度占24.53%。发病时间以换季、冬季为主,分别占35.96%、32.02%。多因素logistic回归分析显示,呼吸道感染、药物过敏史、家族过敏史和食物过敏史是儿童哮喘发病的危险因素(P<0.05)。结论北仑区儿童哮喘发病率较高,具有性别和季节发病差异,应加大对患病危险因素的宣传,规范标准化治疗方案,减少儿童哮喘疾病的发生。 相似文献
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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
3.
Uptake of iodine-123 MIBG by pheochromocytomas, paragangliomas, and neuroblastomas: a histopathological comparison 总被引:2,自引:0,他引:2
J Bomanji D A Levison W D Flatman T Horne P M Bouloux G Ross K E Britton G M Besser 《Journal of nuclear medicine》1987,28(6):973-978
The percentage uptake of [123I]metaiodobenzylguanidine (MIBG) by tumors of the paraganglion system is compared with the number of neurosecretory granules (assessed by both light and electron microscopy) in the subsequently resected tumors in six patients. Iodine-123 MIBG was injected intravenously; the tumor uptake of [123I]MIBG varied between 0.001% and 0.14% of the injected dose per gram of tumor tissue at 22 hr. The number of neurosecretory granules in tissue sections was scored on a scale of I-III. A direct proportional correlation was found between the percentage uptake of [123I]MIBG by the tumor and the number of neurosecretory granules in the tissue sections but not with plasma or urinary catecholamines. This technique for imaging reflects the storage status of the tumor better than plasma and urinary catecholamine measurements. 相似文献
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The requirements, problems and progress of radioimmunotherapy in the management of certain malignancies are described. The future prospects using a two- or three-stage approach are promising. 相似文献
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Israel Liberzon Stephan F Taylor K Luan Phan Jennifer C Britton Lorraine M Fig Joshua A Bueller Robert A Koeppe Jon-Kar Zubieta 《Neuropsychopharmacology》2007,61(9):1030-1038
BACKGROUND: Functional neuroimaging studies have detected abnormal limbic and paralimbic activation to emotional probes in posttraumatic stress disorder (PTSD), but few studies have examined neurochemical mechanisms that underlie functional alterations in regional cerebral blood flow. The mu-opioid neurotransmitter system, implicated in responses to stress and suppression of pain, is distributed in and is thought to regulate the function of brain regions that are implicated in affective processing. METHODS: Here we examined the micro-opioid system with positron emission tomography and the micro-opioid receptor-selective radiotracer [11C] carfentanil in 16 male patients with PTSD and two non-PTSD male control groups, with (n = 14) and without combat exposure (n = 15). Differences in micro-opioid receptor binding potential (BP2) were detected within discrete limbic and paralimbic regions. RESULTS: Relative to healthy controls, both trauma-exposed groups had lower micro-opioid receptor BP2 in extended amygdala, nucleus accumbens, and dorsal frontal and insular cortex but had higher BP2 in the orbitofrontal cortex. PTSD patients exhibited reduced BP2 in anterior cingulate cortex compared with both control groups. Micro-opioid receptor BP2 in combat-exposed subjects without PTSD was lower in the amygdala but higher in the orbitofrontal cortex compared with both PTSD patients and healthy controls. CONCLUSIONS: These findings differentiate the general response of the micro-opioid system to trauma from more specific changes associated with PTSD. 相似文献
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