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971.
Excised cucumber (Cucumis sativus, var. Jin-ian No. 4) cotyledons were incubated with 10 ppm of BA (benzyladenine) or water for 1 h, then thouroughly rinsed with water and grown in darkness on filter paper saturated with different concentrations of mannitol solution. Up to 24 h, the fresh weight, carotenoid, RNA, DNA and lipid contents of cotyledons were determined. Although mannitol solution reduced the effectiveness of BA treatment, in the same condition of osmotic potential, the increases of fresh weight, carotenoid, RNA and DNA contents, as well as the decrease of lipid per cotyledon were always much higher in BA treated tissues. BA enhanced the rate of water uptake by the cotyledons. The fresh weight of BA and 0.2 M mannitol treated cotyledons was equal to that of water control, but the increases of carotenoid and nucleic acid contents and the decrease of lipid were much higher in tho former than the latter. 0.3 M and 0.5 M mannitol solu- tions almost interrupted the water uptake of water and BA treated cotyledons respectively. However, the increases of carotenoid and nucleic acid contents as well as decrease of lipid were still occurred in these conditions. The different osmotic potential did nearly not affect the ratio of the increases of carotenoid and nucleic acid contents between BA treatment and control. It means the effectiveness of BA was almost the same under different osmotic potential It is evident that BA stimulated simultaneously the water uptake and metabolism of the cotyledons. They are probably different processes but closely related to each other. 相似文献
972.
Bai J Guo C Sun W Li M Meng X Yu Y Jin Y Tong D Geng J Huang Q Qi J Fu S 《Molecular biology reports》2012,39(3):2697-2703
Lung cancer is a leading cause of cancer-related death, about 40% human non-small cell lung cancer (NSCLC) patients showed lymph node involvements. However, the precise mechanism for the metastasis is still not fully understood. This study was to analyze the potential molecular mechanism for lung cancer metastasis. In the current study, proteomics analysis by two-dimensional electrophoresis (2-DE) was performed first to identify the differentially expressed protein between the higher metastasis lung adenocarcinoma cell line Anip973 and the lower metastasis lung adenocarcinoma cell line AGZY83-a. We confirmed the result by RT-PCR, immunoblotting and immunocytochemistry analyses in these two cell lines. Then we examined the expression of the differentially expressed protein in tumor tissues of NSCLC patients by immunoblotting and immunohistochemistry analyses. Using 2-DE analysis, we have identified DJ-1 was expressed higher in the higher metastasis Anip973 compared to the parental cell line AGZY83-a, that was confirmed by RT-PCR, immunoblotting and immunocytochemistry analyses. In NSCLC patients?? tumor tissues study, immunoblotting data showed that, DJ-1 expression level was significantly higher in 72.2% (13/18) of NSCLC tissue samples compared to that in paired normal lung tissues (P?=?0.044). Immunohistochemistry analysis demonstrated increased DJ-1 expression in 85 NSCLC tumor tissue samples compared with 7 normal lung tissue samples (P?=?0.044). DJ-1 expression was also found to be significantly correlated with cancer lymphatic metastasis (P?=?0.039). DJ-1 might contribute to the metastasis of NSCLC. 相似文献
973.
974.
在中国文物保护体系下,古道等遗产线路类的文物保护工作尚未能完全对接国际文化线路的保护理念,文化线路的国内文物保护体系和国际保护视野面临无法衔接的困境。以国际文化线路“物质线路”和“衍生要素”的分析视野,将具有申遗背景同时需要对接文物保护工作的米仓道(巴中段)作为对象,通过梳理其时空范畴和价值认知,分别辨析作为国内文物保护体系的交通遗产构成框架,以及对接申遗工作的文化线路衍生遗产要素。基于此,遗产线路衔接国内文物保护体系和“文化线路”申遗保护要求的工作框架得以厘清,可为国内面临类似研究需求的文化线路类遗产提供借鉴。 相似文献
975.
976.
Bing Zhang Zhou Cheng Su Tong Earn Tay Vincent B. C. Tan 《Journal of molecular modeling》2010,16(6):1159-1168
In the current work, CDK5/p25 complexes were pulled apart by applying external forces with steered molecular dynamics (SMD)
simulations. The crucial interactions between the kinase and the activation protein were investigated and the SMD simulations
showed that several activation-relevant motifs of CDK5 leave p25 in sequence during the pulling and lead to an apo-CDK2 like CDK5 structure after separation. Based on systematic examination of hydrogen bond breaking and classical MD/molecular
mechanics-generalized Born/surface area) (MM-GBSA) calculations, a CDK5 activation mechanism by p25 is suggested. This is
the first step towards the systemic development of CDK inhibitors and the mechanism proposed could lead to a better understanding
of the protein–protein recognition characteristics between the kinase and its activator. 相似文献
977.
Jain MR Li Q Liu T Rinaggio J Ketkar A Tournier V Madura K Elkabes S Li H 《Journal of proteome research》2012,11(3):1791-1803
Clinically relevant formalin-fixed and paraffin-embedded (FFPE) tissues have not been widely used in neuroproteomic studies because many proteins are presumed to be degraded during tissue preservation. Recent improvements in proteomics technologies, from the 2D gel analysis of intact proteins to the "shotgun" quantification of peptides and the use of isobaric tags for absolute and relative quantification (iTRAQ) method, have made the analysis of FFPE tissues possible. In recent years, iTRAQ has been one of the main methods of choice for high throughput quantitative proteomics analysis, which enables simultaneous comparison of up to eight samples in one experiment. Our objective was to assess the relative merits of iTRAQ analysis of fresh frozen versus FFPE nervous tissues by comparing experimental autoimmune encephalomyelitis (EAE)-induced proteomic changes in FFPE rat spinal cords and frozen tissues. EAE-induced proteomic changes in FFPE tissues were positively correlated with those found in the frozen tissues, albeit with ~50% less proteome coverage. Subsequent validation of the enrichment of immunoproteasome (IP) activator 1 in EAE spinal cords led us to evaluate other proteasome and IP-specific proteins. We discovered that many IP-specific (as opposed to constitutive) proteasomal proteins were enriched in EAE rat spinal cords, and EAE-induced IP accumulation also occurred in the spinal cords of an independent mouse EAE model in a disability score-dependent manner. Therefore, we conclude that it is feasible to generate useful information from iTRAQ-based neuroproteomics analysis of archived FFPE tissues for studying neurological disease tissues. 相似文献
978.
979.
人小细胞肺癌的发病率虽不及非小细胞肺癌,但其五年生存率却相对低得多,这两种细胞类型不仅在病理类型上表现不同,在许多其它性质上也表现不同。小细胞肺癌是一种异质性疾病,它由几种形态不同的瘤细胞组成,包括非小细胞肺癌在内;它易早期转移,能在肝、脑和骨髓中繁殖,具有L-Dopa胱羧酶,神经原特异的烯醇化酶(enolase),能合成神经递质和多肽激素蛙皮肽等特性。目前已有关于小细胞肺癌的单克隆抗体的报道,我们采用美国N I H建立的小细胞肺癌细胞株SH-77作免疫原,目前尚未见有关抗该细胞株的单克隆抗体的报道,现将我们制备的三个单抗体及其初步特异性鉴定结果简报如下 相似文献
980.
Jin Yanjun He Kun Xiang Peng Wang Xiaodong Tong Lintian Wei Zhen Zhang Xiuyue Song Zhaobin 《Environmental Biology of Fishes》2022,105(9):1139-1151
Environmental Biology of Fishes - We investigated the temporal dynamics of population genetics of the Chinese longsnout catfish (Leiocassis longirostris) given wild population decline due to... 相似文献