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101.
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   
102.
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   
103.
Several research reports delineated the significant role of miRNAs in cancer proliferation, and their modulatory role in cancer mitigation, and drug resistance. Melanoma cells have been acquiring stemness to several chemotherapeutic agents through drug efflux proteins, epigenetic modulation, and DNA repair. miRNAs could be applied as novel therapeutic modalities for treating several kinds of cancers to modulate these mechanisms involved in stemness. Nanocarriers to carry these tumor-targeting miRNAs to modulate stemness are a prominent strategy to overcome their low penetrability, minimal stability, and nonspecificity. We have searched several public databases such as PubMed, Medline, Google scholar, and NLM and obtained the information pertinent to the miRNA-based nanocarrier systems to target stemness through epigenetic modulation in melanomas. This review delineates that various miRNAs can modulate the stemness in melanomas by specific intricate epigenetic signaling, and other cell-based signaling mechanisms. Specific nanocarrier formulations with specific miRNAs are optimal methods to deliver these miRNAs in order to achieve significant entrapment efficiency, loading efficiency, and stability. Furthermore, the combinatorial regimen of FDA-approved chemotherapeutic molecules with tumor-targeting miRNAs and chemotherapy combined with nanocarriers can efficiently deliver the utmost therapeutic window by targeting tumor matrix, invasion, metastasis, and angiogenesis in melanomas. Substantial research should focus on the clinical application of this gene therapy in melanomas using these low immunogenic, highly degradable, and biocompatible combinatorial nanotherapeutic regimens.  相似文献   
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Abstract  Nineteen kinds of spiro enol ether analogues were screened with larvae of Pieris rapae for antifeedant activity. The results showed that the antifeedant activity of compounds No.20 and No. 12 was higher than others. In non-choice test, AFC50 values within 24 h of compounds No.20 and No. 12 against 3rd instar larvae of P. rapae were 226.93 μg/mL and 370.00 μg/mL, and that in choice test against 4th larvae were 280.54 μg/mL and 398.88 μg/mL, respectively. Compd. No.20 could prolong the eggs hatch time and reduce the haemolymph content and the protein content in haemolymph of 4th instar larvae obviously. Compd. No.20 could protect tested leaves and control larvae of P. rapae effectively.  相似文献   
107.
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   
108.
日本紫花牵牛(Pharbilisnilcv.Violet)子叶完全展开后,短日照诱导前、诱导后和两个短日照间的长日照处理对植株的花芽分化都有一定的抑制作用。双向凝胶电泳分析表明,长日照处理的牵牛子叶内存在着短日照处理子叶内没有的两种蛋白质(pI4.1,MW16.5kD;pI4.2,MW16.5kD)。这些蛋白质可能与长日照抑制牵牛植株的花芽分化有一定关系。  相似文献   
109.
分析了陕西省稀有濒危植物46个种(包括种下等级)的地理分布和42个属的分布区类型及其区系特征,提出了稀有濒危植物种质资源的保护对策。  相似文献   
110.
本文测定了湖南产五步蛇蛇毒磷脂酶A2在不同温度保温后的酶活性,结果表明此酶具有一定的热稳定性。  相似文献   
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