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91.
在添加了[Δ]算子Gödeln值命题逻辑系统中,给出了Gödel[n]值命题逻辑系统中有限理论的平均真度的定义,给出了该系统下的一些重要结论并给予证明,验证了在该系统下平均真度的一些基本性质,为进一步在该系统下研究平均真度奠定了基础。 相似文献
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94.
高固体分丙烯酸树脂是目前环保树脂研究的一个很重要的分支,本文选择合适的丙烯酸单体,用溶液聚合法合成了一种高固体分丙烯酸树脂,并详细讨论了反应温度、加料时间及保温时间等工艺条件对合成树脂性能的影响。 相似文献
95.
SANHUA LI QINGHONG KONG XIAOKE ZHANG XINTING ZHU CHUNBO YU CHANGYAN YU NIAN JIANG JING HUI LINGJIE MENG YUN LIU 《Biocell》2022,46(11):2425-2432
Traditional Chinese medicine (TCM) has been increasingly employed in the last decades in China for both preventing and treating a variety of cancers. 3-epi-bufotalin is an active ingredient of TCM “Chanpi” with anti-tumor potential. However, the effect and mechanism of 3-epi-bufotalin on colorectal cancers were not well disclosed. The present study demonstrated that 3-epi-bufotalin could reduce viability, trigger apoptosis, and block the cell cycle at the G2/M stage in colorectal cancer cell lines HT29, RKO, and COLO205 in vitro. Moreover, 3-epi-bufotalin inhibited the JAK1/STAT3 signaling pathway. These results indicated the anti-proliferation ability of 3-epi-bufotalin in colorectal cancer cells. 相似文献
96.
QIANSHAN TAO QING ZHANG HUIPING WANG HAO XIAO MEI ZHOU LINLIN LIU HUI QIN JIYU WANG FURUN AN ZHIMIN ZHAI YI DONG 《Biocell》2022,46(1):159-169
Acute myeloid leukemia (AML) is regarded as a stem cell disease. However, no one unique marker is expressed
on leukemia stem cells (LSC) but not on leukemic blasts nor normal hematopoietic stem cells (HSC). CD34+
CD38- with
or without CD123 or CD44 subpopulations are immunophenotypically defined as putative LSC fractions in AML.
Nevertheless, markers that can be effectively and simply held responsible for the intrinsical heterogeneity of LSC is
still unclear. In the present study, we examined the frequency of three different LSC subtypes (CD34+
CD38-,
CD34+
CD38-
CD123+
, CD34+
CD38-
CD44+
) in AML at diagnosis. We then validated their prognostic significance on
the relevance of spectral features for diagnostic stratification, immune status, induction therapy response, treatment
effect maintenance, and long-term survival. In our findings, high proportions of the above three different LSC
subtypes were all significantly characterized with low complete remission (CR) rate, high relapse/refractory rate, poor
overall survival (OS), frequent FLT3-ITD mutation, the high level of regulatory T cells (Treg) and monocytic
myeloid-derived suppressor cells (M-MDSC). However, there was no significant statistical difference in all kinds of
other clinical performance among the three different LSC groups. It was demonstrated that CD34+
CD38-
subpopulation without CD123 and CD44 might be held responsible for LSC and correlated with an imbalance of
immune cell subsets in AML. 相似文献
97.
Exosomes, especially from mesenchymal stem cells, have attracted extensive attention in regeneration medicine. Mesenchymal stem cells derived exosomes (MSCs-exosomes) have shown anti-inflammatory, anti-oxidant, anti-apoptosis and tissue regeneration effects in a variety of tissue injury repair models. MSCs-exosomes hold many excellent properties such as low immunogenicity, biocompatibility, and targeting capability. With the in-depth study on the generation and function of exosomes, MSCs-exosomes are considered to be the bright stars in the field of regenerative medicine. However, there are still many obstacles to overcome in terms of exosomes isolation, clinical trials and safety evaluation. In this article, what we should focus on about MSCs-exosomes in regeneration medicine will be discussed. 相似文献
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100.
HANG YU HAI MING JINGJING GONG HAITAO LI HUI HUANG KEMING PAN YANG LIU ZHENHUI KANG JIE WEI DONGTIAN WANG 《Bulletin of Materials Science》2013,36(3):367-372
Au/ZnO nanocomposites have been prepared by a simple chemical method. For the first time, the nanocomposites were directly used as photocatalysts for hydroxylation of aromatic hydrocarbons under UV and visible light irradiation. The results show that the as-prepared photocatalysts display high photocatalytic activity for UV and visible catalytic hydroxylation of benzene. Without the assistance of any solvent or additive, high selectivity and high conversion efficiency were still obtained. Different photocatalytic mechanisms were proposed depending on whether excitation happens on ZnO semiconductor or on the surface plasmon band of Au. The former is Au nanoparticles act as electron buffer due to irradiation by UV light and ZnO nanoparticles as reactive sites for hydroxylation of benzene, the latter is that Au nanoparticles act as light harvesters and inject electrons into ZnO conduction band and as photocatalytic sites under visible light irradiation. 相似文献