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11.
Yue Yu Hui-Yu Pan Xin Zheng Fang Yuan Ying-Lin Zhou Xin-Xiang Zhang 《Molecules (Basel, Switzerland)》2022,27(20)
Early cancer diagnosis is essential for successful treatment and prognosis, and modified nucleosides have attracted widespread attention as a promising group of cancer biomarkers. However, analyzing these modified nucleosides with an extremely low abundance is a great challenge, especially analyzing multiple modified nucleosides with a different abundance simultaneously. In this work, an ultrasensitive quantification method based on chemical labeling, coupled with LC-MS/MS analysis, was established for the simultaneous quantification of 5hmdC, 5fdC, 5hmdU and 5fdU. Additionally, the contents of 5mdC and canonical nucleosides could be obtained at the same time. Upon derivatization, the detection sensitivities of 5hmdC, 5fdC, 5hmdU and 5fdU were dramatically enhanced by several hundred times. The established method was further applied to the simultaneous detection of nine nucleosides with different abundances in about 2 μg genomic DNA of breast tissues from 20 breast cancer patients. The DNA consumption was less than other overall reported quantification methods, thereby providing an opportunity to monitor rare, modified nucleosides in precious samples and biology processes that could not be investigated before. The contents of 5hmdC, 5hmdU and 5fdU in tumor tissues and normal tissues adjacent to the tumor were significantly changed, indicating that these three modified nucleosides may play certain roles in the formation and development of tumors and be potential cancer biomarkers. While the detection rates of 5hmdC, 5hmdU and 5fdU alone as a biomarker for breast cancer samples were 95%, 75% and 85%, respectively, by detecting these three cancer biomarkers simultaneously, two of the three were 100% consistent with the overall trend. Therefore, simultaneous detection of multiple cancer biomarkers in clinical samples greatly improved the accuracy of cancer diagnosis, indicating that our method has great application potential in clinical multidimensional diagnosis. 相似文献
12.
Theoretical analysis of nanosecond crystallization kinetics of phase-change optical recording films 下载免费PDF全文
A theoretical investigation of nanosecond crystallization kinetics of the phase-change optical recording films is presented. An extended Kissinger equation for the square-root heating is
derived, which properly describes the temperature evolution of the films by nanosecond laser heating. The extended Kissinger equation was used to explain our previous experimental results. 相似文献
13.
This paper reports the theoretical study of combining Z-scan technique with Gauss-Bessel (GB) beams beside a phase object (PO) to measure the third-order nonlinear susceptibility components.By using this method,the sign of refractive index which depends on the shape of the close aperture Z-scan curve can be easily determined.Meanwhile,the magnitude of nonlinear coefficients can also be deduced by theoretical fit.The proposed method is advantageous for high sensitivity and imposes a lower stress in the cases of fragile materials,since small pulse energy is enough for the measurement of nonlinear coefficients.Predictions of the models are compared with Gaussian Z-scan measurement and GB Z-scan measurement.By using GB beams with a PO,the sensitivity of Z-scan measurements is found to be a factor of over 60 times greater than for Gaussian beams and 2 times greater than for Gaussian-Bessel beams. 相似文献
14.
Synthesis of orientedly bioconjugated core/shell Fe3O4@Au magnetic nanoparticles for cell separation
Orientedly bioconjugated core/shell Fe3O4@Au magnetic nanoparticles were synthesized for cell separation. The Fe3O4@Au magnetic nanoparticles were synthesized by reducing HAuCl4 on the surfaces of Fe3O4 nanoparticles, which were further characterized in detail by TEM, XRD and UV-vis spectra. Anti-CD3 monoclonal antibody was orientedly bioconjugated to the surface of Fe3O4@Au nanoparticles through affinity binding between the Fc portion of the antibody and protein A that covalently immobilized on the nanoparticles. The oriented immobilization method was performed to compare its efficiency for cell separation with the non-oriented one, in which the antibody was directly immobilized onto the carboxylated nanoparticle surface. Results showed that the orientedly bioconjugated Fe3O4@Au MNPs successfully pulled down CD3+ T cells from the whole splenocytes with high efficiency of up to 98.4%, showing a more effective cell-capture nanostructure than that obtained by non-oriented strategy. This developed strategy for the synthesis and oriented bioconjugation of Fe3O4@Au MNPs provides an efficient tool for cell separation, and may be further applied to various fields of bioanalytical chemistry for diagnosis, affinity extraction and biosensor. 相似文献
15.
This paper studies a small f-number metallic lens with depth-modulated slits.Slits filled with dielectric between silver plates are designed to produce desired optical phase retardations based on the particular propagation properties of surface plasmon polaritons in nanostructures.Numerical simulation of this structure is performed through the finitedifference time-domain method.Different from the conventional dielectric lens,the metallic lens can be used as a pure phase element without energy loss brought by the light refraction at curved surfaces and total internal reflection.The focusing performance is consequently improved,with larger diffraction efficiency than that of the same shaped dielectric lens. 相似文献
16.
Optical nonlinearity measurement of 4-(N-methyl, N-hydroxyethl)amino, 4'-nitroazobenzene using a transmittance technique with a phase object (T-PO) with top-hat beams at 600-nm wavelength 下载免费PDF全文
The transmittance technique with a phase object(T-PO),for measuring optical nonlinear coefficients is proposed with a top-hat beam.The sensitivity of the T-PO with a top-hat beam is a factor of 4 greater than that with a Gaussian beam.The validity of this method is verified by measuring the nonlinearity of a well-characterized liquid,CS 2 at 532-nm wavelength.The ease of use of this method has been proved by measuring a new compound 4-(N-methyl,N-hydroxyethyl)amino,4’-nitroazobenzene(ANAB) at 600-nm wavelength,indicating that this method can be extended to the measurement of optical nonlinearities in a wide-band spectrum. 相似文献
17.
18.
Liang Ying-Lin Yin Liang-Jun Bui Hao-Van Jian Xian Yang Guang Ding Jie-Xiong 《Physics of the Solid State》2019,61(8):1450-1455
Physics of the Solid State - The main objective of this paper is to reveal the mechanism of enhanced excitation light absorption in nano-pores structure BaMgAl10O17:Eu2+ (BAM) phosphor by optical... 相似文献
19.
Zhou Jian-Liang Li Yi-Zhi Zheng He-Gen Xin Xin-Quan Yin Tao Wang Yu-Xiao Song Ying-Lin 《Transition Metal Chemistry》2004,29(2):185-188
The [MoO0.75S3.25Cu3Cl(bipy)2] complex was synthesized for nonlinear optical studies by the reaction of (NH4)2[MoOS3], CuCl and bipy in CH2Cl2 solution. A single crystal X-ray analysis revealed that the complex consists of a nest-shaped core. The Mo atom is tetrahedrally coordinated by four S atoms, or three S atoms and one terminal O atom. There are two types of copper atom in the MoO0.75S3.25Cu3 aggregate: two copper atoms are tetrahedrally coordinated and another copper atom is trigonally coordinated. The third-order nonlinear optical properties were investigated by the Z-scan technique with 8 ns laser pulses at 532 nm. The cluster exhibits both optical self-focusing and optical nonlinear absorption (effectively n
2 = 1.3 × 10–11 e.s.u.,
2 = 1.2 × 10–10 m W–1 in a 2.68 × 10–4 mol dm–3 CH2Cl2 solution). 相似文献
20.
0IntroductionThereiscurrentlyintenseresearchinterestinde-velopingnewnonlinearmaterialswithhighthird-ordernonlinearopticaleffectsduetotheirpotentialapplica-tionsinanumberofimportanttechnologiesincludingopticalpowerlimitingforsensorprotection,opticalswitches,allopticalsignalprocessingandopticalcom-puting犤1~3犦.Metalcomplexeswithplanar,π-conjugatedtetradentateorbidentateligandareofparticularinterestbecausetheycontainbothelectronsthatarefreetomovewithintheπextendedsystemoftheligand… 相似文献