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There was developed a little-work-consuming and non-expensive microdiffu- sion method of carboxyhaemoglobin determination in bloody in low range concentration. It can be used in the assessment of passive smokers' exposure to carbon monoxide. The amount of blood neccessary for the determination was 0.15 ml. An average precision of the developed method of the carbon monoxide determination (converting into HbCO) for the concentration ranged from 1 to 5%, from 3 to 12% and from 5 to 20% was respectively 5.96, 4.09 and 2.14.
The air qualities of four areas in Imo State with a total of twenty two locations were monitored for a period six months with respect to CO level using Gasman air monitor (Crowcon Instruments Ltd, England. The air quality monitoring was conducted in the morning, afternoon and evening hours within dry and wet seasons in order to elucidate the variability of this atmospheric pollutant in the study locations. The results obtained showed significant variation of the air pollutant in the morning, afternoon and evening including within the twenty four weeks, and between dry and wet seasons. The mean values of CO in the dry season are in the order Egbema > Okigwe > Owerri > Orlu, while the order for the mean CO level in wet season is Okigwe > Orlu > Egbema > Owerri. Elevated concentration of CO was observed in the study areas above 10 ppm, the Nigerian National ambient air quality standard. This observation calls for health and environmental concern. Hence, anthropogenic activities and fugitive emission sources of atmospheric pollutants such as increased vehicular traffic, biomass combustion, use of electric power generating sets, leakages from incinerators and flare stacks should be seriously monitored.
Carbon monoxide (CO) is an odorless, tasteless and colorless gas which is generated by heme oxygenase enzymes (HOs). HOs degrade heme releasing equimolar amounts of CO, iron and biliverdin, which is subsequently reduced to bilirubin. CO shares many properties with nitric oxide (NO), an established cellular messenger. Both CO and NO are involved in neural transmission and modulation of blood vessel function, including their relaxation and inhibition of platelet aggregation. CO, like NO, binds to heme proteins, although CO binds only ferrous (Fell) heme, whereas NO binds both ferrous and ferric (Felll). CO enhances the activity of guanylate cyclase although it is less potent than NO. In contrast, CO inhibits other heme proteins, such as catalase or cytochrome P450. The effects of CO on gene expression can be thus varied, depending on the cellular microenvironment and the metabolic pathway being influenced. In this review the regulation of gene expression by HO/CO in the cardiovascular system is discussed. Recent data, derived also from our studies, indicate that HO/CO are significant modulators of inflammatory reactions, influencing the underlying processes such as cell proliferation and production of cytokines and growth factors.
The high-altitude laboratory of greenhouse gas measurement, KASLAB, was founded on the Polish mountain Kasprowy Wierch in 1994. In the direct neighborhood of the measuring point there are no significant sources of compounds measured at the station. However, the measuring point may be affected by periodic anthropogenic emissions from the nearby Podhale region, with Zakopane the most popular tourist resort (6 km to the north and 1 km below Kasprowy Wierch). Periodic air enrichment in CO content detected at the KASLAB station indicates a prior contact of air masses that reach Kasprowy Wierch with the lower layer of the troposphere and can be used for qualitative and quantitative evaluation of trace gas emissions (for example CO2) from regions with strong anthropopression. Data analysis performed for 2010 presented in this paper revealed that the anthropogenic component of carbon dioxide observed at Kasprowy Wierch usually does not exceed 2 ppm, occasionally reaching a value of 10 ppm. Respiration component of atmospheric CO2 concentration at Kasprowy Wierch can be as high as 35 ppm.
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Cyclic GMP metabolism and its role in brain physiology

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Cyclic GMP (cGMP) is synthesized by guanylyl cyclase (GC) in response to nitric oxide (NO) and carbon monoxide (CO) or natiuretic peptides (NPs); atrial, brain and C-type (ANP, BNP and CNP). cGMP is degraded by several cGMP-specific phosphodiesterases (PDEs). Guanylate cyclases (GC) are differentiated into: membrane-bound/particulate (pGC) and cytosolic/soluble (sGC). In recent years evidence has accumulated that NO is the main activator of sGC and NO/cGMP plays important role in glutaminergic, cholinergic and dopaminergic signaling pathways. cGMP in the nervous system is involved in long term potentiation and depression (LTP, LTD) suggesting its participation in learning and memory mechanism. cGMP regulates calcium homeostasis and phototransduction. Its level is regulated by PDEs and their specific inhibitors protect cGMP level in cells and are very important from clinical point of view.
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