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141.
随着污水厂出水排放标准日益提高,对排水中粪大肠菌群的控制也越来越严格。现场电解制次氯酸钠发生系统是一种较为理想的环境友好型氯消毒技术,能够有效杀灭城镇污水处理厂出水中的粪大肠杆菌。因原水水质不同,次氯酸钠的杀菌效果会有差异。次氯酸钠对原水中的氨氮有一定的去除作用,但是有可能氧化原水中残留的有机氮,从而使得氨氮含量重新升高。现场连续投加试验中,反应池次氯酸钠浓度为1.2mg/L,出水中的粪大肠菌群始终稳定达到GB18918-2002一级A标准的要求,且其他水质指标(如氨氮、COD等)良好。  相似文献   
142.
    
One of the major mediators of neuroinflammation in PD is tumour necrosis factor alpha (TNF-α), which, similar to other cytokines, is produced by activated microglia and astrocytes. Although TNF-α can be neuroprotective in the brain, long-term neuroinflammation and TNF release can be harmful, having a neurotoxic role that leads to death of oligodendrocytes, astrocytes, and neurons and, therefore, is associated with neurodegeneration. Apart from cytokines, a wide family of molecules with homologous structures, namely chemokines, play a key role in neuro-inflammation by drawing cytotoxic T-lymphocytes and activating microglia. The objective of the current study was to examine the levels of the serum TNF-α and CCL2 (Chemokine (C-C motif) ligand 2), also known as MCP-1 (Monocyte Chemoattractant Protein-1), in PD patients compared with healthy controls. We also investigated the associations between the serum levels of these two inflammatory mediators and a number of clinical symptoms, in particular, disease severity and cognition. Such an assessment may point to their prognostic value and provide some treatment hints. PD patients with advanced stage on the Hoehn–Yahr scale showed an increase in TNF-α levels compared with PD patients with stages 1 and 2 (p = 0.01). Additionally, the UPDRS score was significantly associated with TNF-α levels. CCL2 levels, however, showed no significant associations.  相似文献   
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144.
    
Mass spectrometry has become the gold standard for the identification of proteins in proteomics. In this review, I will discuss the available literature on proteomic experiments that analyze human cerebrospinal fluid (CSF) and brain extracellular fluid (ECF), mostly obtained by cerebral microdialysis. Both materials are of high diagnostic value in clinical neurology, for example, in cerebrovascular disorders like stroke, neurodegenerative diseases like Alzheimer's Disease, Parkinson's Disease, amyotrophic lateral sclerosis (ALS), traumatic brain injury and cerebral infectious and inflammatory disease, such as multiple sclerosis. Moreover, there are standard procedures for sampling. In a number of studies in recent years, biomarkers have been proposed in CSF and ECF for improved diagnosis or to control therapy, based on proteomics and mass spectrometry. I will also discuss the needs for a transition of research‐based experimental screening with mass spectrometry to fast and reliable diagnostic instrumentation for clinical use. © 2008 Wiley Periodicals, Inc., Mass Spec Rev 29:17–28, 2010  相似文献   
145.
粪便水对大坦沙污水厂生产运行的影响及控制措施   总被引:1,自引:0,他引:1  
广州市大坦沙污水处理厂承担着全市粪便水的处理任务。生产实践表明,由粪便水造成的水质冲击负荷对生产运行不利,导致设备维护率提高、运行成本增加。通过建造粪便水调节池、调整工艺参数、加大设备维修和技术改造力度、对恶臭源进行加盖除臭等措施可以降低粪便水对生产运行的影响。  相似文献   
146.
科学家已经研究获得了大量的蛋白质/多肽潜在生物标志物,这些生物标志物需要经过验证和确证才能进一步转化到临床应用.针对蛋白质/多肽的绝对定量研究在标志物验证和确证过程中起到关键作用.传统的蛋白质定量方法,如酶联免疫吸附试验(ELISA)技术存在蛋白质抗体难以获得、不同抗体批次之间存在差异、基于抗体的检测存在交叉反应等问题...  相似文献   
147.
脑卒中是一类高致残率、高死亡率的脑血管疾病,分为缺血性脑卒中和出血性脑卒中2种亚型,二者具有相似的临床症状,但治疗策略完全不同.目前,主要依赖医学影像学技术进行诊断,但存在耗时、费用高、难以区分2种脑卒中亚型等缺点,进而影响疾病治疗和预后.本研究收集了59例健康志愿者、60例急性脑缺血和36例脑出血患者的血浆样本,运用...  相似文献   
148.
We examined a suite of environmental contaminants and exposure endpoints in blackcrowned night-heron (Nycticorax nycticorax, BCNH) embryos collected in 2002 from colonies in Illinois, Minnesota, and Virginia. Embryos from the Lake Calumet, IL, colony had greater exposure to polychlorinated biphenyls (PCBs), 4,4’-dichlorodiphenyldichloroethylene (DDE), dieldrin, transnonachlor, oxychlordane, cobalt, copper, and selenium than did those from northwest MN and coastal VA. Embryos from IL and VA contained greater concentrations of mercury and zinc than those from MN, whereas the latter had greater accumulation of lead. Greater exposure of IL embryos to PCBs was reflected in greater ethoxyresorufin-O-deethylase and benzyloxyresorufin-O-dealkylase induction. However, measures of oxidative stress and genotoxicity were similar to those in embryos from the other colonies examined, and no overt toxic effects of contaminant exposure such as embryo mortality or malformations were observed. Although efforts to clean up the south Chicago environment are ongoing, Lake Calumet BCNH, and undoubtedly other piscivorous wildlife foraging in the region, continue to be exposed to a variety of environmental contaminants. Life-history characteristics of this species make it ideal as an environmental sentinel for the success of the cleanup of the south Chicago environment.  相似文献   
149.
A chemometric class modelling strategy (unequal dispersed classes – UNEQ) was applied for the first time as a possible screening method to monitor the abuse of growth promoters in veal calves. Five serum biomarkers, known to reflect the exposure to classes of compounds illegally used as growth promoters, were determined from 50 untreated animals in order to design a model of controls, representing veal calves reared under good, safe and highly standardised breeding conditions. The class modelling was applied to 421 commercially bred veal calves to separate them into ‘compliant’ and ‘non-compliant’ with respect to the modelled controls. Part of the non-compliant animals underwent further histological and chemical examinations to confirm the presence of either alterations in target tissues or traces of illegal substances commonly administered for growth-promoting purposes. Overall, the congruence between the histological or chemical methods and the UNEQ non-compliant outcomes was approximately 58%, likely underestimated due to the blindness nature of this examination. Further research is needed to confirm the validity of the UNEQ model in terms of sensitivity in recognising untreated animals as compliant to the controls, and specificity in revealing deviations from ideal breeding conditions, for example due to the abuse of growth promoters.  相似文献   
150.
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