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排序方式: 共有1476条查询结果,搜索用时 15 毫秒
51.
Adriana Gadioli Tarone Luiz Henrique Fasolin Fabiana de Assis Perrechil Míriam Dupas Hubinger Rosiane Lopes da Cunha 《Food and Bioproducts Processing》2013,91(2):111-120
Soy protein fractions rich in β-conglycinin (7S) or glycinin (11S) were freeze dried or spray dried at temperatures of 120, 150 or 180 °C. The fractions were characterized for their particle size distribution, sorption isotherms and by scanning differential calorimetry. The gelling capacity of the protein fractions was studied at pH values of 3 and 7 using oscillatory measurements, mechanical properties and water holding capacity. The rheological measurements showed that viscous modulus (G″) predominated at low temperatures and the elastic modulus (G′) at high temperatures. At pH 3, the G′–G″ crossover occurred at lower temperatures when compared to pH 7. This behaviour was more accentuated for the 11S fractions due to its capacity to form stronger gels. An increase of drying temperature led to a displacement of the gel point to higher temperatures and decreased the elasticity modulus or gelling capacity of protein fractions. These results were confirmed by the mechanical properties, since at higher temperatures the gels were more fragile and brittle, especially when formed at pH 7. 相似文献
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Gámbaro A Raggio L Dauber C Claudia Ellis A Toribio Z 《Archivos latinoamericanos de nutrición》2011,61(3):308-315
The relationship between nutritional knowledge and the consumption frequency of preferred food-types was studied among one sample of Uruguayan consumers. A locally-adapted version of Parmenter & Wardle's General Nutrition Knowledge Questionnaire and a food consumption survey based on 39 food groups were completed by a total of 270 participants. Cluster Analysis enabled the identification of two clusters showing different levels of nutritional knowledge--cluster 1 (n = 177) and cluster 2 (n = 93), providing an average of 73.6% and 52.9% of correct answers, respectively. These clusters differed significantly (p < or = 0.05) in age and educational distribution--cluster 1 was composed mainly by older adults and persons with a higher educational level. A number of areas were identified where nutritional knowledge was extremely poor, as was the case with the recommended daily fruit and vegetable intake and the caloric content of the nutrients. Overall, nutritional knowledge was found to have a positive influence on food preferences and consumption frequency, those participants with a higher nutritional knowledge reporting a higher consumption of fruits, vegetables and low-fat products, in addition to a lower consumption of high-fat and high-sugar foods. 相似文献
54.
Based on the assumption of true moving bed processes it was demonstrated that integration of a racemization reaction into a continuous chromatographic process can improve the production of single enantiomers. In view of possible practical implementations, the analysis is extended to more realistic simulated moving bed (SMB) processes. Superstructures of SMB‐based systems are defined that reflect the three general concepts of flow sheet, partial, and total process integration. Process candidates are generated by simultaneously optimizing process structure and operating conditions. Optimal process setups are determined under idealized conditions as a function of the purity requirement. The best performance is achieved by fully integrated processes. These are compared under more realistic conditions to units with side reactors. The results indicate that a simple fully integrated SMB system with three zones is a particularly promising new process option. The new concept is investigated in detail to identify relevant practical aspects. 相似文献
55.
Cytotoxic Activity and Structure–Activity Relationship of Triazole‐Containing Bis(Aryl Ether) Macrocycles 下载免费PDF全文
Dr. Eduardo Hernández‐Vázquez Dr. Alejandra Chávez‐Riveros Dr. Adriana Romo‐Pérez María Teresa Ramírez‐Apán Dr. Alma D. Chávez‐Blanco Dr. Rocío Morales‐Bárcenas Dr. Alfonso Dueñas‐González Dr. Luis D. Miranda 《ChemMedChem》2018,13(12):1193-1209
Cancer continues to be a worldwide health problem. Certain macrocyclic molecules have become attractive therapeutic alternatives for this disease because of their efficacy and, frequently, their novel mechanisms of action. Herein, we report the synthesis of a series of 20‐, 21‐, and 22‐membered macrocycles containing triazole and bis(aryl ether) moieties. The compounds were prepared by a multicomponent approach from readily available commercial substrates. Notably, some of the compounds displayed interesting cytotoxicity against cancer (PC‐3) and breast (MCF‐7) cell lines, especially those bearing an aliphatic or a trifluoromethyl substituent on the N‐phenyl moiety (IC50<13 μm ). Additionally, some of the compounds were able to induce apoptosis relative to the solvent control; in particular, (Z)‐N‐cyclohexyl‐7‐oxo‐6‐[4‐(trifluoromethyl)phenyl]‐11H‐3,10‐dioxa‐6‐aza‐1(4,1)‐triazola‐4(1,3),9(1,4)‐dibenzenacyclotridecaphane‐5‐carboxamide ( 12 f ) was the most potent in this regard (22.7 % of apoptosis). 相似文献
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Panagiotis Sarantis Alexandros Bokas Adriana Papadimitropoulou Evangelos Koustas Stamatios Theocharis Pavlos Papakotoulas Dimitrios Schizas Alexandros Papalampros Evangelos Felekouras Athanasios G. Papavassiliou Michalis V. Karamouzis 《International journal of molecular sciences》2021,22(13)
Pancreatic Cancer (PC) is recognized as a highly thrombogenic tumor; thus, low-molecular-weight heparin (LMWH) such as tinzaparin is routinely used for PC patients. On the basis of combinatorial therapy approaches to treat highly malignant and refractory cancers such as PC, we hypothesized that tinzaparin can augment the effectiveness of traditional chemotherapeutic drugs and induce efficient antitumor activity. PANC-1 and MIAPaCa-2 were incubated alone or in combination with tinzaparin, nab-paclitaxel and gemcitabine. In vivo evaluation of these compounds was performed in a NOD/SCID mouse using a model injected with PANC-1. Tinzaparin enhances the anti-tumor effects of nab-paclitaxel and gemcitabine in mtKRAS PC cell lines via apoptosis in in vitro experiments. The triple combination power acts through the induction of apoptosis, reduction of the proliferative potential and angiogenesis; hence, contributing to a decrease in tumor volume observed in vivo. The triple regimen provided an extra 24.3% tumor reduction compared to the double combination (gemcitabine plus nab-paclitaxel). Combinatorial strategies can create novel therapeutic approaches for the treatment of patients with PC, achieving a better clinical outcome and prolonged survival. Further prospective randomized research is needed and the investigation of various concentrations of tinzaparin above 150 UI/Kg, would potentially provide a valuable synergistic effect to the conventional therapeutic compounds. 相似文献
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Pâmela Maria Moreira Fonseca Luciano dos Santos Feitosa Adriana Barrinha Fernandes Ranato Amaro Zângaro Walter Miyakawa Carlos José de Lima 《臭氧:科学与工程》2015,37(1):85-89
Ozone gas diluted in water has been shown to produce significant results in terms of the elimination of microorganisms. Streptococcus mutans is the etiologic agent of dental caries. Methods using water containing ozone and an ultrasonic cleaner were employed for the disinfection of a curette. Streptococcus mutans was grown in a selective medium. The curette was submitted to disinfection by water containing ozone, by ultrasound, and then both techniques were combined. The results show that either method produced a significant microbial reduction, but the efficacy of both methods combined was greater. This method of disinfection proved to be both viable and cheap. 相似文献
60.
Luminita-Ioana Buruiana Ecaterina Avram Adriana Popa 《Polymer-Plastics Technology and Engineering》2015,54(7):671-681
Blends of quaternized polysulfones with triphenylphosphonium pendant groups/poly(vinylidene fluoride) were analyzed to establish their impact on the rheological, morphological and surface properties, as well as their interactions with some blood compounds. The rheological functions reflect the influence of both polymers’ chemical structures. Blend compositions of the corresponding films influence the surface tension parameters, increase blend hydrophobicity and, implicitly, decrease the polar surface tension parameters. The specific surface characteristics of polymer blends are related to their interactions with some blood constituents and plasma proteins. Also, the specific microarchitecture of the blend represents an excellent scaffold for medical applications. 相似文献