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61.
褪黑素是由松果体分泌的一种吲哚胺,在各种生理活动中起着关键作用,包括调节昼夜节律、免疫应答、氧化过程及细胞凋亡。近年来,褪黑素的抗肿瘤特性逐渐引起关注。大量研究发现,褪黑素在急性胰腺炎早期过程中起保护作用,可通过细胞凋亡途径抑制胰腺癌细胞的产生,且可通过自噬作用调节胰腺内分泌激素的合成分泌从而影响胰腺内分泌肿瘤的发展。由此,褪黑素可能影响胰腺疾病的发展,但其对胰腺疾病的作用机理尚未完全明确。本文综述了近几年褪黑素与胰腺疾病的研究进展,分析了褪黑素在胰腺疾病中的作用,以及褪黑素联合化疗药物对胰腺癌的治疗作用。 相似文献
62.
Guosheng Su Xiaodong Xiao Jin Du Jingjie Zhang Peirong Zhang Zhanqiang Liu Chonghai Xu 《The International Journal of Advanced Manufacturing Technology》2020,107(1):73-83
Since Dr. Carl Salomon proposed the well-known hypothesis on cutting temperatures in 1931, the debate on the hypothesis has never stopped. It shows that ev 相似文献
63.
基于微型传感技术、嵌入式边缘计算和LoRa物联网,提出了一种新型的电缆外力扰动分布式监测技术。并针对LoRa数据传输的低密度、窄带宽要求,基于振动信号的时频特征,提出了一种精简化的特征集、状态集和控制集的单包数据装载方法。通过试验初步获得了电缆振动特征集的典型范围,为建立基于物联网窄带通信方式的电缆外力扰动智能预警系统提供了基础。 相似文献
64.
Ying Guo Mengting Ma Fan Jiang Wenqian Jiang Hanxin Wang Shuang-kui Du 《International Journal of Food Science & Technology》2020,55(2):720-728
Protein quality and antioxidant properties of soymilk derived from black soybean (eight varieties) in China were analysed following in vitro simulated gastrointestinal digestion (including dialysis). Soymilk from black soybean possessed high okara weight but low yield, protein content and sensory scores. The in vitro digestibility of protein in all black soymilk samples was higher than 60%, and the Shenmu black soybean exhibited the highest digestibility. Non-digested milk from the black soybean exhibited significantly high total phenolic content (TPC) (127.15–173.04 mg/100 mL), ferric-reducing antioxidant power (FRAP) (272.18–366.27 μmol L−1) and DPPH free radical-scavenging activity (61.20–83.81%). These parameters were significantly lower in the non-digested soymilk than those in soymilk after gastric digestion but higher than those of soymilk in the dialysed fraction. Gastric digestion significantly increased bioactive compound levels released from black soymilk, and the bioaccessibility of phenolic compounds was 24.37–36.05%. Hence, black soymilk was sufficiently available for human absorption. 相似文献
65.
Zu Guoqing Lu Yukuan Yan Yi Zhang Xiaoming Zhao Jingwei Du Wei Ran Xu Jiang Zhengyi 《Metals and Materials International》2020,26(2):248-259
Metals and Materials International - The flow behaviour and microstructure characteristics of a ferritic stainless steel were investigated using plain strain compression test on a Gleeble 3500... 相似文献
66.
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68.
Kang Du Jun Fan Zheng-Yu Zou Xiao-Qiang Song Wen-Zhong Lu Wen Lei 《Journal of the American Ceramic Society》2020,103(11):6369-6377
Low-permittivity Ca1−xSrxSnSiO5 (0 ≤ x ≤ 0.45) microwave dielectric ceramics were prepared via traditional state-reaction at 1400°C-1450°C for 5 hours. Moreover the microwave dielectric properties of SnO2 ceramic were obtained for the first time. SnO2 ceramic was difficult to densify, and SnO2 ceramic (ρrel = 65.1%) that was sintered at 1525°C exhibited the optimal microwave dielectric properties of εr = 5.27, Q × f = 89 300 GHz (at 14.5 GHz), and τf = −26.7 ppm/°C. For Ca1−xSrxSnSiO5 (0 ≤ x ≤ 0.15) ceramics, Sr2+ could be dissolved in the Ca2+ site of Ca1−xSrxSnSiO5 to form a single phase, and the partial substitution of Ca2+ by Sr2+ could improve the microwave dielectric properties of CaSnSiO5 ceramic. Secondary phases (SnO2 and SrSiO3) appeared at 0.2 ≤ x ≤ 0.45 and could adjust the abnormally positive τf value of CaSnSiO5 ceramic. The highest Q × f value (60 100 GHz at 10.4 GHz) and optimal microwave dielectric properties (εr = 9.42, Q × f = 47 500 GHz at 12.4 GHz, and τf = −1.2 ppm/°C) of Ca1−xSrxSnSiO5 ceramics were obtained at x = 0.05 and 0.45, respectively. 相似文献
69.
Neoteric Mn2+-activated Cs3Cu2I5 yellow-emitting halides were achieved by the simple solid-state reaction route. The near-ultraviolet light was the suitable excitation lighting source for the resultant halides. The resultant halides exhibited bright yellow emission under the excitation of 378 nm and the optimum dopant content was 11 mol%. The multipole-multipole interaction contributed to the concentration quenching mechanism and the critical distance was 28.65 Å. The thermal resistance of the prepared compounds was identified by the temperature-dependent emission spectra. Ultimately, the designed light-emitting diode showed bright white light with satisfied color rendering index, proper color coordinate, and suitable correlated color temperature. These results indicated that the prepared yellow-emitting halides were suitable for indoor illumination. 相似文献
70.
具有一定曲率外形的铝合金整体壁板属于典型的多筋零部件,传统弯曲成形工艺成形困难,容易产生多种缺陷。提出了离散填料辅助滚弯成形整体2A12T4铝合金壁板滚弯工艺,并通过实验与整体填料滚变成形进行了对比,同时采用有限元模拟技术,探究了离散填料辅助整体壁板滚弯成形中的影响因素。研究结果表明:填料数量、上下垫板厚度等因素对成形性能影响较大,填料在3~6块时成形稳定,可以有效地避免筋条屈曲与失稳;随垫板厚度增加,壁板表面圆弧更加光滑、连续,但是回弹性增强;上下垫板分别在10~20 mm厚度时,综合性能较好。通过离散填料辅助滚弯技术可以成形出质量较高的整体壁板。 相似文献