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Our study aims to discuss the association between inflammation-related factors such as single nucleotide polymorphisms (SNPs) with susceptibility and recurrence in nasopharyngeal carcinoma. We used Taqman real-time polymerase chain reaction (PCR) to characterize the genetic variation of five SNPs in 194 nasopharyngeal carcinoma patients and 231 healthy subjects. All statistical analysis is performed with statistical product and service solutions v13.0; odds ratio (OR) value and 95 % confidence interval (CI) were calculated. There is no relationship between TGFβ1 -869 T/C, IL-6 -634C/G, TGFβ1 -509C/T, IL1 -511C/T and nasopharyngeal carcinoma susceptibility. Both single factor and multiple factors analysis showed that IL1a -889 T/T genotype is significantly associated with nasopharyngeal carcinoma in decreasing the risk of nasopharyngeal carcinoma. A highly significant association was found between IL1a -889 T/T genotype and protective genotype as defined by various pathological types. This is more obvious in the protective genotype of the non-keratin-type squamous carcinoma undifferentiated type. We also discovered that genotype G/G and C/G + G/G of IL6 -634 gene are associated with reduced recurrence of nasopharyngeal carcinoma. IL1a -889 gene polymorphism and susceptibility is related to nasopharyngeal carcinoma and can potentially decrease the risk of nasopharyngeal carcinoma in the Han Chinese population in north China. IL1- 889 TT genotype is protective genotype for nasopharyngeal carcinoma. We have provided evidence that the GG genotype of the IL6 -634 gene is associated with recurrent risk of nasopharyngeal carcinoma. The G allele is the protective gene of nasopharyngeal carcinoma recurrence. [ABSTRACT FROM AUTHOR]

At present, the way to introduce the sample into the inductively coupled plasma atomic emission spectrometry (ICP-AES) light source is still in the form of solution. In order to improve the treatment effect of the aqueous solution and change its physical properties, the surface tension and viscosity under different experimental conditions were measured with magnetic stirring combined with laser irradiation. . The treated samples were introduced into the inductively coupled plasma (ICP) to measure the spectral line intensity, signal-to-background ratio, excitation temperature and electron density emitted by the ICP source. The experimental results showed that: when the magnetic stirrer rotate speed was 1 197 r·min-1, the laser power density was 0.227 6 W·cm-2 and irradiation for 15 min, the surface tension and viscosity of the solution were decreased by 27.85% and 8.66% respectively than those of the untreated solution. As to the element spectral lines of As 188.980 nm, Cd 214.439 nm, Cr 267.716 nm, Cu 324.754 nm, Hg 253.652 nm and Pb 220.353nm: the intensity was enhanced 32.07%, 65.36%, 18.27%, 32.29%, 19.38% and 54.28%; the signal-to-background ratio increased by 25.13%, 60.97%, 18.18%, 27.69%, 21.11% and 48.93%, respectively. The enhancement of the plasma radiation was explained to a certain extent by measuring the excitation temperature and electron density of the plasma. The processing method of the aqueous solution can effectively improve the spectral intensity and signal-to-background ratio of the ICP. Compared with the laser irradiation aqueous solution separately, this method significantly shortened the processing time, improve the efficiency. This method is simple, with no secondary pollution in the treatment of the sample solution, convenient popularization and use.

In order to change the physical properties of aqueous solution and improve the radiation intensity of the ICP emission spectrum, the effects of different laser power density and irradiation time on the surface tension and viscosity of aqueous solution were investigated by using near infrared laser at 976 nm and CO2 laser at 10. 6 µm to irradiate aqueous solution orthogonally, then the enhancement of ICP spectral intensity with processed solution was discussed. The results showed that the surface tension and viscosity of aqueous solution reduced by 42. 13% and 14. 03% compared with the untreated, and the atomization efficiency increased by 51.26% at the laser power density 0. 265 7 W . cm-2 of 976 nm and 0. 206 9 W . cm-2 of CO2 laser with 40 min irradiation time. With the optimized aqueous solution introduced into the ICP source, the spectral line intensity of sample elements As, Cd, Cr, Hg and Pb was enhanced by 46.29%, 94. 65%, 30. 76%, 33.07% and 94. 58% compared to the untreated aqueous solution, while the signal-to-background ratio increased by 43. 84%, 85. 35%, 28. 71%, 34. 37% and 90. 91%, respectively. Plasma temperature and electron density also increased by 5. 94% and 1. 18% respectively. It is obvious that the method of double-beam laser orthogonal irradiation on solution can reduce the surface tension and viscosity of aqueous solution significantly, and raise the radiationintensity of ICP source, and will provide a better condition for detecting the trace heavy metal elements in water samples.

In order to reduce the effect of the spectral line self-absorption on the analysis result in the laser induced plasma and enhance the qualities of spectrum, the spectral information was recorded by the spectral analysis system consisting of a modular multifunctional grating spectrometer and a CCD detector etc., and the electron temperature and electron density of the plasma were measured with the spectroscopic methods. A plane mirror device was used to constraint the laser plasma, and a reasonable explanation was got through comparing the linear evolution under different experimental conditions and measuring the temperature, electronic density and sample evaporation. The result shows that when an appropriate plane mirror device was used to constraint the laser plasma, the axial temperature of the plasma increased and the radial distribution of the plasma becomes uniform; the electron density increased dramatically; however, obviously sample evaporation decreased, which may be the reasons for being able to effectively reduce the level of self-absorption spectral lines. Therefore, the plane mirror device could reduce the self-absorption effect in the laser-induced plasma. This makes it possible to choose a sensitive line that acts as analysis line in the quantitative analysis of the major elements. In other words, this promotes the measurement precision in the laser-induced break-down spectroscopy.