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951.
为了确定粗纤维调节素(Un) 是否具有促进成纤维细胞Ⅰ型胶原合成的作用, 我们采用地高辛原位杂交和斑点杂交技术, 观察了Un 对小鼠成纤维细胞(NIH/3T3) Ⅰ型前胶原m RNA转录的影响; 结果发现Un 对体外培养的3T3 细胞Ⅰ型前胶原基因转录具有促进作用; 提示Un 不仅作为一种细胞外基质而存在, 并且还有促进胶原合成的功能。 相似文献
952.
953.
Y Dai K A Carayanniotis P Eliades P Lymberi P Shepherd Y c Kong G Carayanniotis 《Journal of immunology (Baltimore, Md. : 1950)》1999,162(12):6987-6992
Thyroglobulin (Tg)-specific Abs occur commonly in thyroid disease, but it is not clear to what extent they affect Tg processing and presentation to T cells. Here we show that generation of the nondominant pathogenic Tg epitope (2549-2560), containing thyroxine (T4) at position 2553 (T4(2553)), is augmented by Tg-specific IgG mAbs that facilitate FcR-mediated internalization of Tg. However, other mAbs of the same (IgG1) subclass enhanced Tg uptake by APC but had no effect on the generation of this peptide. Treatment of APC with chloroquine or glutaraldehyde abrogated enhanced generation of T4(2553). The boosting effect was selective, since the enhancing mAbs did not facilitate generation of the neighboring cryptic (2495-2511) peptide, which is also pathogenic in mice. When Tg was simultaneously complexed to a mAb reactive with T4(2553) and to a mixture of boosting mAbs, the presentation of this epitope was totally suppressed. These results suggest that Tg-specific Abs alter Tg processing and may boost or suppress the presentation of nondominant pathogenic determinants during the course of disease. 相似文献
954.
香椿离体快繁技术研究 总被引:5,自引:3,他引:2
6~7月取香棒当年生半木质化、具腋芽的茎段为外植体,诱导腋芽萌发,进行繁殖培养。通过大量试验,筛选出各阶段适宜的培养基组成。萌芽诱导阶段培养在MS+6-BA0.2mg/L中,腋芽萌发早,生长快;在继代和增殖培养中以MS+6-BA0.2mg/L效果较好,MS+ZT0.2mg/L+GA32.0mg/L次之。培养30天繁殖倍数3.1~4.0,在仅含MS有机元素。铁盐减半、蔗糖15g/L的固体培养基中,附 相似文献
955.
开封沙地试验区不同作物种植方式的综合效益评价 总被引:9,自引:0,他引:9
开封沙区地处河南省沙区腹地,风沙灾害严重,旱涝灾害频繁,地力瘠薄,严重障碍着沙区农牧业生产的发展。因此,自1983年在国家科技攻关的基础上建立了开封沙地试验区,探索平原沙区农业生产的发展模式。尤其是“八五”攻关期间,深化农林牧复合生态系统的优化研究,... 相似文献
956.
Long Ma Qiushi Ruan Wenwen Zha Lingqiao Kong ZhengMing Sun 《Liver Transplantation》2024,14(11):2303586
Photo-assisted ion batteries demonstrate remarkable potential for portable and decentralized solar energy utilization, due to their profound capacity enhancement under irradiation accompanied by promoted discharge voltages. However, ion batteries in practice are highly compact with limited surface area for irradiation. Overcoming the size limit for irradiation is a challenge. Herein, an irradiation spillover effect in photo-assisted ion batteries is demonstrated, that is the impact of irradiation on the battery is not restrained within the irradiated area but can spillover the whole electrode. This phenomenon is a consequence of the light-induced potential difference between irradiated and unirradiated regions, leading to selective ion insertion. Irradiated regions favored H+ insertion due to light-induced proton-coupled electron transfer, while unirradiated regions preferred Zn2+ insertion. Consequently, the capacity enhancement remains unaffected by halving the irradiated area. This study overcomes the irradiation size limit for photo-assisted ion batteries and encourages highly integrated photo-assisted ion batteries for practice application. 相似文献
957.
Zhi Li Yu Zhang Kang Zhou Taoyi Kong Xing Zhou Yaming Hao Xin Huang Jie Xu Yuwen Cheng Haimei Liu Ziyang Guo Yonggang Wang 《Liver Transplantation》2024,14(15):2303786
Sodium-ion batteries (SIBs), based on hard carbon anodes and Na+-intercalation compound cathodes, have gained significant attention. Nonetheless, hard carbon anodes involve the storage of Na+ at a low potential, typically below 0.1 V (vs Na/Na+), which increases the risk of dendritic Na growth on the anode surface during overcharging. Herein, a safe organic/inorganic composite anode containing tetrasodium 3,4,9,10-perylenetetracarboxylate (Na4PTC) and Metallic bismuth (Bi) with a weight ratio of 7:2, which exhibits an average potential of 0.7 V (vs Na+/Na) and a capacity of 150 mAh g−1 is proposed. The electrode reaction involves a reversible coordination reaction within the organic host and alloying reactions within the metallic Bi component. Importantly, the organic component efficiently buffers the volume changes in Bi during the alloying reaction, while the metallic Bi enhances the electronic conductivity of the organic material. As a result, this composite anode shows high cycle stability and rate performance, even under high mass loadings ranging from 10 to 50 mg cm−2. Furthermore, it is demonstrated that the Na-ion full cell, consisting of the composite anode and the Na3V2O2(PO4)2F cathode, exhibits minimal capacity degradation over 100 cycles while maintaining a high areal capacity of 1.1 mA cm−2. 相似文献
958.
Soybean(Glycine max) is a major source of plant protein and oil.Soybean breeding has benefited from advances in functional genomics.In particular,the release of soybean reference genomes has advanced our understanding of soybean adaptation to soil nutrient deficiencies,the molecular mechanism of symbiotic nitrogen(N) fixation,biotic and abiotic stress tolerance,and the roles of flowering time in regional adaptation,plant architecture,and seed yield and quality.Nevertheless,many challenges remain... 相似文献
959.
960.
Tao Zhang Guangquan Zhang Wenbo Yang Hongze Chen Jisheng Hu Zhongjie Zhao Chundong Cheng Guanqun Li Yu Xie Yilong Li Rui Kong Yongwei Wang Gang Wang Hua Chen Xue-Wei Bai Shangha Pan Bei Sun Le Li 《Cell death & disease》2021,12(11)
Chronic pancreatitis (CP) is described as progressive inflammatory fibrosis of pancreas, accompanied with irreversible impaired endocrine and exocrine insufficiency. Pancreatic stellate cells (PSCs) are widely distributed in the stroma of the pancreas and PSCs activation has been shown as one of the leading causes for pancreatic fibrosis. Our previous study has revealed that autophagy is dramatically activated in CP tissues, which facilitates PSCs activation and pancreatic fibrosis. Long non-coding RNAs (LncRNAs) have been recognized as crucial regulators for fibrosis-related diseases. LncRNAs interact with RNA binding protein or construct competitive endogenous RNA (ceRNA) hypothesis which elicited the fibrotic processes. Until now, the effects of lncRNAs on PSCs activation and pancreatic fibrosis have not been clearly explored. In this study, a novel lncRNA named Lnc-PFAR was found highly expressed in mouse and human CP tissues. Our data revealed that Lnc-PFAR facilitates PSCs activation and pancreatic fibrosis via RB1CC1-induced autophagy. Lnc-PFAR reduces miR-141 expression by suppressing pre-miR-141 maturation, which eventually upregulates the RB1CC1 and fibrosis-related indicators expression. Meanwhile, Lnc-PFAR enhanced PSCs activation and pancreatic fibrosis through trigging autophagy. Our study interrogates a novel lncRNA-induced mechanism in promoting the development of pancreatic fibrosis, and Lnc-PFAR is suggested to be a prospective therapeutic target in clinical scenarios.Subject terms: RNAi, Diagnostic markers, Chronic pancreatitis 相似文献