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51.
为研究异叶三宝木(Trigonostemon heterophyllus)的二萜成分及其抗菌活性,采用硅胶柱层析、凝胶柱层析、高效液相色谱对萃取物进行分离纯化,结合现代波谱技术对所得化合物进行结构鉴定,并通过牛津杯法和2倍稀释法检测化合物对革兰氏阴性菌大肠杆菌(Escherichia coli)以及革兰氏阳性菌肺炎双球菌(Pneumococcus)的生长抑制活性和MIC值。从异叶三宝木中分离得到了6个化合物,包括5个二萜类, 1个木脂素类,分别鉴定为trigonochinene E (1)、neoboutomannin (2)、6,9-O- dedimethyltrigonostemone (3)、stelltian B (4)、3,4-secosonderianol (5)、biondinin A (6)。化合物1、2、3、5对大肠杆菌有抑制作用,MIC值分别为9.375、18.75、18.75、18.75 μg/mL。化合物2、3、4、6为首次从该种植物中分离得到,化合物4为首次从该属植物中分离得到。除化合物4外,其他化合物都有一定的抗菌活性,且化合物1、2、3对大肠杆菌抑制作用强于阳性对照硫酸卡那霉素。 相似文献
52.
本文以粤油 116花生(Arachis hypogaea L.)为材料,对不同处理种子的除子叶“种胚”(以下简称“种胚”)的蛋白质进行了研究.实验结果表明,当花生种子活力下降到一定程度时,其“种胚”内出现一种新蛋白质( pI6.2、MW 10 KD),随种子老化程度加深,含量逐渐增多.我们认为该蛋白质与花生种子老化存在着一定的相关关系,可作为该种子老化的标志. 相似文献
53.
Diversity in nucleotide acquisition by antigenically similar Chlamydia psittaci of avian origin 总被引:2,自引:0,他引:2
Abstract Two different nucleic acid precursor utilization patterns were obtained for five avian isolates of Chlamydia psittaci . Three of the isolates bahaved in a manner similar to that previously described, showing total dependency on the host cell for ribonucleoside triphosphates and being unable to utilize medium-supplied thymidine. In contrast, the other two isolates were incapable of taking pyrimidine ribonucleotides from the host cell and they could efficiently utilize medium-supplied thymidine. These unusual isolates were resistant to 5-fluorouridine while the other three isolates were sensitive. Of the five isolates only 6BC was sensitive to sulfonamides. The five isolates were divided into two groups by comparing the Alu I restriction endonuclease patterns obtained following digestion of the major outer membrane protein (OMP1) gene, amplified by the polymerase chain reaction. The OMP1 genotyping results were confirmed by serotyping. 相似文献
54.
Lisong Hu Zhongping Xu Rui Fan Guanying Wang Fuqiu Wang Xiaowei Qin Lin Yan Xunzhi Ji Minghui Meng Soonliang Sim Wei Chen Chaoyun Hao Qinghuang Wang Huaguo Zhu Shu Zhu Pan Xu Hui Zhao Keith Lindsey Henry Daniell Jonathan F. Wendel Shuangxia Jin 《Plant biotechnology journal》2023,21(1):78-96
Zanthoxylum armatum and Zanthoxylum bungeanum, known as ‘Chinese pepper’, are distinguished by their extraordinary complex genomes, phenotypic innovation of adaptive evolution and species-special metabolites. Here, we report reference-grade genomes of Z. armatum and Z. bungeanum. Using high coverage sequence data and comprehensive assembly strategies, we derived 66 pseudochromosomes comprising 33 homologous phased groups of two subgenomes, including autotetraploid Z. armatum. The genomic rearrangements and two whole-genome duplications created large (~4.5 Gb) complex genomes with a high ratio of repetitive sequences (>82%) and high chromosome number (2n = 4x = 132). Further analysis of the high-quality genomes shed lights on the genomic basis of involutional reproduction, allomones biosynthesis and adaptive evolution in Chinese pepper, revealing a high consistent relationship between genomic evolution, environmental factors and phenotypic innovation. Our study provides genomic resources and new insights for investigating diversification and phenotypic innovation in Chinese pepper, with broader implications for the protection of plants under severe environmental changes. 相似文献
55.
Ting Liu Hengcheng Zhu Minghuan Ge Zhou Pan Yan Zeng Yan Leng Kang Yang Fan Cheng 《Journal of cellular and molecular medicine》2023,27(16):2328-2339
Few approaches have been conducted in the treatment of renal cell carcinoma (RCC) after nephrectomy, resulting in a high mortality rate in urological tumours. Mitophagy is a mechanism of mitochondrial quality control that enables selective degradation of damaged and unnecessary mitochondria. Previous studies have found that glycerol-3-phosphate dehydrogenase 1-like (GPD1L) is associated with the progression of tumours such as lung cancer, colorectal cancer and oropharyngeal cancer, but the potential mechanism in RCC is still unclear. In this study, microarrays from tumour databases were analysed. The expression of GPD1L was confirmed by RT–qPCR and western blotting. The effect and mechanism of GPD1L were explored using cell counting kit 8, wound healing, invasion, flow cytometry and mitophagy-related experiments. The role of GPD1L was further confirmed in vivo. The results showed that GPD1L expression was downregulated and positively correlated with prognosis in RCC. Functional experiments revealed that GPD1L prevented proliferation, migration and invasion while promoting apoptosis and mitochondrial injury in vitro. The mechanistic results indicated that GPD1L interacted with PINK1, promoting PINK1/Parkin-mediated mitophagy. However, inhibition of PINK1 reversed GPD1L-mediated mitochondrial injury and mitophagy. Moreover, GPD1L prevented tumour growth and promoted mitophagy by activating the PINK1/Parkin pathway in vivo. Our study shows that GPD1L has a positive correlation with the prognosis of RCC. The potential mechanism involves interacting with PINK1 and regulating the PINK1/Parkin pathway. In conclusion, these results reveal that GPD1L can act as a biomarker and target for RCC diagnosis and therapy. 相似文献
56.
卡特拉鱼形态,食性和生长的研究 总被引:6,自引:0,他引:6
观测卡特拉鱼的形态特征和1—3龄鱼主要可量性状及其比例的变动。1—3龄鱼除主食商品饲料外,同时也食较大比例的浮游生物。着重对浮游生物的种类和比例进行了分析。肠长与体长呈直线相关。Y=6.38X-89.95。1—4龄鱼体长和体重相对生长率和生长指标都随年龄增加而逐渐下降。体长与体重呈曲线相关。W=0.00002261L~(3.0569)。采用 Von.Bertalanffy 生长方程分析其生长特性。方程参数 L_∞=821.2mm,W_∞=19616.6g,t_0=0.6年,K=0.3。体长生长不具拐点,生长速度随年龄增加而递减;体重生长具拐点,其值4.3年。此时体重生长速度达最大值。4、3龄前是生长旺盛期,此后进入生长缓慢期。 相似文献
57.
Yunqiang Zhang Jianyu Liu Lu Guan Dongxue Fan Feiruo Xia Andong Wang Ying Bao Yongnan Xu 《化学与生物多样性》2023,20(3):e202200940
Zea mays (Z. mays) is one of the main cereal crops in the world, and it′s by-products have exhibited medicinal properties to explore. This article intends to review the chemical compositions and pharmacological activities of by-products of Z. mays (corn silks, roots, bract, stems, bran, and leaves) which support the therapeutic potential in the treatment of different diseases, with emphasis on the natural occurring compounds and detailed pharmacological developments. Based on this review, 231 natural compounds are presented. Among them, flavonoids, terpenes, phenylpropanoids, and alkaloids are the most frequently reported. The by-products of Z. mays possess diuretic effects, hepatoprotective, anti-diabetic, antioxidant, neuroprotective, anti-inflammatory, anti-cancer, plant protection activity, and other activities. This article reviewed the phytochemistry and pharmacological activities of Z. mays for comprehensive quality control and the safety and effectiveness to enhance future application. 相似文献
58.
Han Tian Jin-Lin Yang Yirui Deng Wenhao Tang Ruiping Liu Chenyang Xu Peng Han Hong Jin Fan 《Liver Transplantation》2023,13(1):2202603
The progress of aqueous zinc batteries (AZBs) is limited by the poor cycling life due to Zn anode instability, including dendrite growth, surface corrosion, and passivation. Inspired by the anti-corrosion strategy of steel industry, a compounding corrosion inhibitor (CCI) is employed as the electrolyte additive for Zn metal anode protection. It is shown that CCI can spontaneously generate a uniform and ≈30 nm thick solid-electrolyte interphase (SEI) layer on Zn anode with a strong adhesion via Zn O bonding. This SEI layer efficiently prohibits water corrosion and guides homogeneous Zn deposition without obvious dendrite formation. This enables reversible Zn deposition and dissolution for over 1100 h under the condition of 1 mA cm−2 and 1 mAh cm−2 in symmetric cells. The Zn-MnO2 full cells with CCI-modified electrolyte deliver an ultralow capacity decay rate (0.013% per cycle) at 0.5 A g−1 over 1000 cycles. Such an innovative strategy paves a low-cost way to achieve AZBs with long lifespan. 相似文献
59.
二氢叶酸还原酶结合底物的去除 总被引:1,自引:1,他引:0
分析了应用氨甲蝶呤(MTX-Agarose)亲和层析法提纯的鸡肝二氢叶酸还原酶的组成和性质.建立了用平面粒度胶等电聚焦法去除与酶紧密结合底物的方法.讨论了结合底物对酶构象研究的影响,并指出,用未完全去除结合底物的酶研究酶在变性过程构象变化会得到错误的结论. 相似文献
60.