| 1. |
- He, C. J., et al.
(författare)
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Advance in chemical mimic of Fe-only hydrogenase
- 2004
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Ingår i: Huaxue jinzhan. - 1005-281X. ; 16:2, s. 250-255
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Tidskriftsartikel (refereegranskat)abstract
- Hydrogenases are one of the important enzymes in many microorganisms, which can catalyze the reversible oxidation of hydrogen. They are classified into three categories according to their active metal centers, that is, Fe-only, [Ni-Fe] and metal free H-2 ases. This review introduces primarily the recent advances in structural investigation and chemical mimic of Fe-only H-2 ases.
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| 2. |
- He, Sailing, et al.
(författare)
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Synchrotron radiation photoemission study of Yb2.75C60
- 2005
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Ingår i: Wuli xuebao. - : Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences. - 1000-3290. ; 54:3, s. 1400-1405
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Tidskriftsartikel (refereegranskat)abstract
- The Yb275C60 thin film was prepared and studied by using the synchrotron radiation ultraviolet photoemission spectroscopy(PES) in an ultrahighvacuum system. The spectral line obtained in the range between the Fermi level and ～5 eV binding energy consists of those lines from the valence band (the molecular orbital LUMO, HOMO and HOMO1 derived energy bands of C60) and core levels(Yb 4f7/2 and 4f5/2). Taking into account the variations of the photoinization cross sections of C 2p and Yb 4f with different photon energies, we have measured the photoemission spectra under the condition of varying photon energies, and carried out simulations to deduce the component contributions. The peak positions, widths and intensities for the components are obtained quantitatively. The results reveals that the photoemission of 4f electrons has a significant intensity with the photon energies larger than ～300 eV, and that the measured spectra depart drastically from the density of states of the valence band. To observe the valence band structure, one should carry out the PES measurements by using photons with energies less than 300 eV. The photoionization crosssection oscillation is also observed in Yb275C60 with almost the same oscillation period as that for pure C60 However, the oscillation amplitude is obviously smaller than that for pure C60, which reveals that the chemical environment of C60 in compounds has nonnegligible effects on the photoionization crosssection oscillation phenomenon.
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| 3. |
- Li, Hui-xiang, et al.
(författare)
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[Expressions of thymidine phosphorylase, thymidylate synthase and dihydropyrimidine dehydrogenase in breast cancer and their correlations with prognosis]
- 2004
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Ingår i: Zhonghua zhong liu za zhi [Chinese journal of oncology]. - Beijing, China : Zhongguo Yixue Kexueyuan / Cancer Hospital, Chinese Academy of Medical Sciences. - 0253-3766. ; 26:11, s. 669-672
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Tidskriftsartikel (refereegranskat)abstract
- Objective: To study the expression of thymidine phosphorylase (TP), thymidylate synthase (TS) and dihydropyrimidine dehydrogenase (DPD) mRNA in breast cancer and its correlation with prognosis.Methods: Expression levels of TP, TS and DPD mRNA in 86 micro-selected breast cancer tissues and 9 normal breast tissues were detected by real-time quantitative PCR.Results: The median expression levels of TP, TS and DPD mRNA in tumor tissue and in normal tissues were 16.54, 0.38, 2.47 and 11.75, 0.25, 8.33, respectively, there were no significant differences (P >0.05). The expression levels of TP, TS and DPD mRNA showed no association with tumor size, lymph node metastasis, pathological grade and clinical stage, except that of DPD showed a negative association with patients' ages. There was no significant difference in disease-free survival or overall survival between the patients with high and low TP or DPD mRNA levels. Disease-free survival tends to be better in the patients with low TS mRNA level than those with high TS mRNA, but the difference was not significant (P=0.069), while the overall survival showed a statistically difference (59.00 month and 70.30 month) (P=0.0496).Conclusion: The expression level of TS mRNA may serve as a prognostic marker for breast cancer patients.
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