Background: The prognosis of patients with tumors is partly influenced by the stage when patients are diagnosed. Therefore, the time of confirmed diagnosis after onset can be considered as a prognostic predictor. Alth...Background: The prognosis of patients with tumors is partly influenced by the stage when patients are diagnosed. Therefore, the time of confirmed diagnosis after onset can be considered as a prognostic predictor. Although a few of studies work on it, factors that influence the duration remain poorly understood in different areas. Methods: This retrospective study involved patients with gastric cancer. Participants completed questionnaires by either phone or face-to-face interviews. Results: Females are with a longer interval than males. Farms lived in rural area and with New Rural Cooperative Medical Scheme are associated with a longer time interval. Patients whose income is mainly from their spouses also have a longer interval. Abdominal pain seems to be associated with longer interval time, while vomiting leads to a shorter time interval. Taking medicine after symptoms appear is associated with longer time intervals, especially those take medicine nonstandardly and more than 2 weeks. Conclusions: The results demonstrate that the medical resource in rural area should still be enhanced;meanwhile taking medicine without doctor’s advice should be cut down. Additional efforts must be made to devise strategies to properly guide patients’ behavior.展开更多
Geopolymer is a new type of eco-friendly cementitious material, and its superior drying and high temperature resistance has been widely recognized. The service performance of geopolymer under 150 ℃ high-temperature h...Geopolymer is a new type of eco-friendly cementitious material, and its superior drying and high temperature resistance has been widely recognized. The service performance of geopolymer under 150 ℃ high-temperature hydrothermal conditions is still less discussed. In this paper, the mechanical strength of pure metakaolin system with low calcium content and metakaolin-cement system with high calcium content under hydrothermal and non-hydrothermal conditions were studied. The results show that under 150 ℃ hydrothermal conditions, the strength of pure metakaolin geopolymer sharply decreases by reduction rate of 81.8% compared to the sample under 150 ℃ drying conditions, while the strength of metakaolin-cement geopolymers is well retained with only a slight decrease of 14.4%. This is mainly because the predominantly hydration product sodium aluminosilicate(N-A-S-H) gel of pure metakaolin system undergoes the process of “dissociation–repolymerization–crystallization” under 150 ℃ hydrothermal conditions, resulting in the loss of cementation ability and obvious deterioration of mechanical strength. In the metakaolin-cement system, the high-calcium calcium silicate gel(C-A-S-H)gel maintains a stable structure, thereby maintaining the macroscopic strength of the material under the hydrothermal conditions.展开更多
A series of structurally well-defined iron-dinitrogen complexes(LFe-N2)bearing cyclopentadienylphosphine ligands(L)were synthesized and analyzed by single-crystal X-ray structural analysis,IR/Raman spectra,magnetometr...A series of structurally well-defined iron-dinitrogen complexes(LFe-N2)bearing cyclopentadienylphosphine ligands(L)were synthesized and analyzed by single-crystal X-ray structural analysis,IR/Raman spectra,magnetometry,Mössbauer spectroscopy,and elemental analysis.The conversion relationship and the change of the spin states among the iron complexes with different valences were studied in detail.展开更多
文摘Background: The prognosis of patients with tumors is partly influenced by the stage when patients are diagnosed. Therefore, the time of confirmed diagnosis after onset can be considered as a prognostic predictor. Although a few of studies work on it, factors that influence the duration remain poorly understood in different areas. Methods: This retrospective study involved patients with gastric cancer. Participants completed questionnaires by either phone or face-to-face interviews. Results: Females are with a longer interval than males. Farms lived in rural area and with New Rural Cooperative Medical Scheme are associated with a longer time interval. Patients whose income is mainly from their spouses also have a longer interval. Abdominal pain seems to be associated with longer interval time, while vomiting leads to a shorter time interval. Taking medicine after symptoms appear is associated with longer time intervals, especially those take medicine nonstandardly and more than 2 weeks. Conclusions: The results demonstrate that the medical resource in rural area should still be enhanced;meanwhile taking medicine without doctor’s advice should be cut down. Additional efforts must be made to devise strategies to properly guide patients’ behavior.
基金supported by the State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development (20YYGZ-KF-GC-04)。
文摘Geopolymer is a new type of eco-friendly cementitious material, and its superior drying and high temperature resistance has been widely recognized. The service performance of geopolymer under 150 ℃ high-temperature hydrothermal conditions is still less discussed. In this paper, the mechanical strength of pure metakaolin system with low calcium content and metakaolin-cement system with high calcium content under hydrothermal and non-hydrothermal conditions were studied. The results show that under 150 ℃ hydrothermal conditions, the strength of pure metakaolin geopolymer sharply decreases by reduction rate of 81.8% compared to the sample under 150 ℃ drying conditions, while the strength of metakaolin-cement geopolymers is well retained with only a slight decrease of 14.4%. This is mainly because the predominantly hydration product sodium aluminosilicate(N-A-S-H) gel of pure metakaolin system undergoes the process of “dissociation–repolymerization–crystallization” under 150 ℃ hydrothermal conditions, resulting in the loss of cementation ability and obvious deterioration of mechanical strength. In the metakaolin-cement system, the high-calcium calcium silicate gel(C-A-S-H)gel maintains a stable structure, thereby maintaining the macroscopic strength of the material under the hydrothermal conditions.
基金supported by the Basic Science Center of Transformation Chemistry of Key Components of Air,National Natural Science Foundation of China(no.21988101).
文摘A series of structurally well-defined iron-dinitrogen complexes(LFe-N2)bearing cyclopentadienylphosphine ligands(L)were synthesized and analyzed by single-crystal X-ray structural analysis,IR/Raman spectra,magnetometry,Mössbauer spectroscopy,and elemental analysis.The conversion relationship and the change of the spin states among the iron complexes with different valences were studied in detail.
