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171.
The use of nanomaterials rationally engineered to treat cancer is a burgeoning field that has reported great medical achievements. Iron-based polymeric nano-formulations with precisely tuned physicochemical properties are an expanding and versatile therapeutic strategy for tumor treatment. Recently, a peculiar type of regulated necrosis named ferroptosis has gained increased attention as a target for cancer therapy. Here, we show for the first time that novel iron oxide nanoparticles coated with gallic acid and polyacrylic acid (IONP–GA/PAA) possess intrinsic cytotoxic activity on various cancer cell lines. Indeed, IONP–GA/PAA treatment efficiently induces ferroptosis in glioblastoma, neuroblastoma, and fibrosarcoma cells. IONP–GA/PAA-induced ferroptosis was blocked by the canonical ferroptosis inhibitors, including deferoxamine and ciclopirox olamine (iron chelators), and ferrostatin-1, the lipophilic radical trap. These ferroptosis inhibitors also prevented the lipid hydroperoxide generation promoted by the nanoparticles. Altogether, we report on novel ferroptosis-inducing iron encapsulated nanoparticles with potent anti-cancer properties, which has promising potential for further in vivo validation.  相似文献   
172.
桑蚕种良卵率是蚕种质量检验的重要指标,控制样本间卵粒数的偏差是保证良卵率准确性的关键。通过对桑蚕卵粒重的调查分析,得出其分布服从正态分布。若从一批蚕种中抽取1g卵作为样本,则来自同一总体的2个样本的卵粒数之差不超过16粒,其置信概率为95%;当置信概率取99%时,两个样本的卵粒数之差不超过21粒。文章为蚕业生产提供了一种实用的克卵粒数偏差控制方法。  相似文献   
173.
The drugs delivery system in the treatment of diseases has advantages such as reduced toxicity, increased availability of the drug, etc. Therefore, studies of the supramolecular interactions between local anesthetics (LAs) butamben (BTB) or ropivacaine (RVC) complexed with 2-hydroxypropyl-β-cyclodextrin (HP-βCD) and carried in Stealth liposomal (SL) are performed. 1H-NMR nuclear magnetic resonance (DOSY and STD) were used as the main tools. The displacements observed in the 1H-NMR presented the complexion between LAs and HP-βCD. The diffusion coefficients of free BTB and RVC were 7.70 × 10−10 m2 s−1 and 4.07 × 10−10 m2 s−1, and in the complex with HP-βCD were 1.90 × 10−10 m2 s−1 and 3.64 × 10−10 m2 s−1, respectively, which indicate a strong interaction between the BTB molecule and HP-βCD (98.3% molar fraction and Ka = 72.279 L/mol). With STD-NMR, the encapsulation of the BTB/HP-βCD and RVC/HP-βCD in SL vesicles was proven. Beyond the saturation transfer to the LAs, there is the magnetization transfer to the hydrogens of HP-βCD. BTB and RVC have already been studied in normal liposome systems; however, little is known of their behavior in SL.  相似文献   
174.
引入单直和子空间的概念,证明了线性空间可唯一分解为单直和子空间的直和,并且给出了计算方法.  相似文献   
175.
埋地热油管道正常运行的数值模拟研究   总被引:2,自引:0,他引:2  
对高凝原油管道输送的水力热力问题进行分析研究,掌握管线运行规律,保证管线安全经济运行有着重要意义.本文建立了埋地热油管道正常运行的数学模型,采用非结构化网格和有限容积法对该问题进行了研究,计算结果与实验测量值吻合良好.  相似文献   
176.
This study aimed to evaluate the antibacterial activity in vitro of Salpianthus macrodontus and Azadirachta indica extracts against potentially pathogenic bacteria for Pacific white shrimp. Furthermore, the extracts with higher inhibitory activity were analyzed to identify compounds responsible for bacterial inhibition and evaluate their effect on motility and biofilm formation. S. macrodontus and A. indica extracts were prepared using methanol, acetone, and hexane by ultrasound. The minimum inhibitory concentration (MIC) of the extracts was determined against Vibrio parahaemolyticus, V. harveyi, Photobacterium damselae and P. leiognathi. The polyphenol profile of those extracts showing the highest bacterial inhibition were determined. Besides, the bacterial swimming and swarming motility and biofilm formation were determined. The highest inhibitory activity against the four pathogens was found with the acetonic extract of S. macrodontus leaf (MIC of 50 mg/mL for Vibrio spp. and 25 mg/mL for Photobacterium spp.) and the methanol extract of S. macrodontus flower (MIC of 50 mg/mL for all pathogens tested). Both extracts affected the swarming and swimming motility and the biofilm formation of the tested bacteria. The main phenolic compounds related to Vibrio bacteria inhibition were naringin, vanillic acid, and rosmarinic acid, whilst hesperidin, kaempferol pentosyl-rutinoside, and rhamnetin were related to Photobacterium bacteria inhibition.  相似文献   
177.
薄层色谱-紫外可见分光光度法测定食品中的苏丹红Ⅰ号   总被引:1,自引:0,他引:1  
建立了测定食品中苏丹红Ⅰ号新方法:薄层色谱-紫外可见分光光度法.方法的线性回归方程为:A=0.00583 0.15105ρ,在0.50~10.0 μg/mL之间苏丹红Ⅰ号的浓度与吸光度之间呈线性关系,相关系数R=0.9992,检出限为0.05 μg/mL.测定结果与国家标准HPLC法对照,令人满意.可用于食品中苏丹红Ⅰ号的测定.  相似文献   
178.
The geometrical effect of chlorine atom positions in polyatomic molecules after capturing a low-energy electron is shown to be a prevalent mechanism yielding Cl2. In this work, we investigated hexachlorobenzene reduction in electron transfer experiments to determine the role of chlorine atom positions around the aromatic ring, and compared our results with those using ortho-, meta- and para-dichlorobenzene molecules. This was achieved by combining gas-phase experiments to determine the reaction threshold by means of mass spectrometry together with quantum chemical calculations. We also observed that Cl2 formation can only occur in 1,2-C6H4Cl2, where the two closest C–Cl bonds are cleaved while the chlorine atoms are brought together within the ring framework due to excess energy dissipation. These results show that a strong coupling between electronic and C–Cl bending motion is responsible for a positional isomeric effect, where molecular recognition is a determining factor in chlorine anion formation.  相似文献   
179.
Biomphalaria glabrata snails constitute the main vector of schistosomiasis in Brazil, and Bauhinia monandra Kurz, the leaves of which contain BmoLL lectin with biocidal action, is a plant widely found on continents in which the disease is endemic. This work describes the composition of B. monandra preparations and the effect on embryos and adult snails, their reproduction parameters and hemocytes. We also describe the results of a comet assay after B. glabrata exposure to sublethal concentrations of the preparations. Additionally, the effects of the preparations on S. mansoni cercariae and environmental monitoring with Artemia salina are described. In the chemical evaluation, cinnamic, flavonoid and saponin derivatives were detected in the two preparations assessed, namely the saline extract and the fraction. Both preparations were toxic to embryos in the blastula, gastrula, trochophore, veliger and hippo stages (LC50 of 0.042 and 0.0478; 0.0417 and 0.0419; 0.0897 and 0.1582; 0.3734 and 0.0974; 0.397 and 0.0970 mg/mL, respectively) and to adult snails (LC50 of 6.6 and 0.87 mg/mL, respectively), which were reproductively affected with decreased egg deposition. In blood cell analysis, characteristic cells for apoptosis, micronucleus and binucleation were detected, while for comet analysis, different degrees of nuclear damage were detected. The fraction was able to cause total mortality of the cercariae and did not present environmental toxicity. Therefore, B. monandra preparations are promising in combating schistosomiasis since they can control both the intermediate host and eliminate the infectious agent, besides being safe to the environment.  相似文献   
180.
α-氨基膦酸酯的合成方法研究进展   总被引:2,自引:0,他引:2  
从Lewis催化剂合成法、非Lewis催化剂合成法、绿色合成法3个方面综述了近年来国内外在α-氨基膦酸酯合成研究领域的最新进展.参考文献33篇.  相似文献   
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