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151.
152.
Boulaiz H Alvarez PJ Prados J Marchal J Melguizo C Carrillo E Peran M Rodríguez F Ramírez A Ortíz R Aránega A 《International journal of molecular sciences》2011,12(11):7445-7458
Breast cancer research has developed rapidly in the past few decades, leading to longer survival times for patients and opening up the possibility of developing curative treatments for advanced breast cancer. Our increasing knowledge of the biological pathways associated with the progression and development of breast cancer, alongside the failure of conventional treatments, has prompted us to explore gene therapy as an alternative therapeutic strategy. We previously reported that gef gene from E. coli has shown considerable cytotoxic effects in breast cancer cells. However, its action mechanism has not been elucidated. Indirect immunofluorescence technique using flow cytometry and immunocytochemical analysis were used to detect breast cancer markers: estrogen (ER) and progesterone (PR) hormonal receptors, human epidermal growth factor receptor-2 proto-oncogene (c-erbB-2), ki-67 antigen and p53 protein. gef gene induces an increase in ER and PR expressions and a decrease in ki-67 and c-erbB-2 gene expressions, indicating a better prognosis and response to treatment and a longer disease-free interval and survival. It also increased p53 expression, suggesting that gef-induced apoptosis is regulated by a p53-mediated signaling pathway. These findings support the hypothesis that the gef gene offers a new approach to gene therapy in breast cancer. 相似文献
153.
Lilia L. Méndez‐Lagunas Ana María Pineda Reyes León Raúl Hernández Ochoa Juan Rodríguez Ramírez 《European Journal of Lipid Science and Technology》2011,113(6):780-785
In this study we evaluated the efficiency of six extraction methods for emu fat based on the quantification of yield, color, density, refraction index, and rheological behavior. Both physical methods (Bain Marie, rotary evaporator, fusion, ultrasound, and microwave) and chemical methods (solvents) were evaluated. Oil properties were compared with commercial emu oil as a reference. Solvent‐based extraction produced the greatest yield (72.8%). Among the physical methods, the greatest yield was produced by the ultrasound method (42.8%). In general, properties were similar to those reported for vegetable oils. The rotary evaporator method showed the greatest difference in total color (ΔE) in comparison with a commercially‐produced reference, while the fusion method showed the smallest ΔE. No statistically significant differences were found between the density and refraction index of the treated samples and those of the reference. Kinematic viscosity increased significantly in samples extracted via microwave method. All samples displayed pseudoplastic behavior. The data showed a good fit to the power law model (R2 > 0.90). The consistency coefficient and flow behavior index were determined for all methods. Practical applications: Therapeutic applications for oil have been posited for emu oil. In pharmaceutical products, oils are used as emollients and as carriers for medicinal substances. The practical importance of an oil depends on its physical properties, thus a thorough understanding of those physical properties is very important for identifying potential applications. These properties are affected by the extraction method employed; the present paper evaluates the effects of a range of extraction methods on yield efficiency, as well as physical and rheological properties. Novel extraction methods such as ultrasound and microwave are also evaluated in this study. 相似文献
154.
Franco M. Rabagliati Daniela E. Yañez Daniel Canales Raúl Quijada Paula A. Zapata 《Polymer Bulletin》2013,70(7):2111-2123
The copolymerization of styrene with cyclohexene, 1-methyl-1-cyclohexene, and norbornene using ethenylbisindenylzirconium dichloride and methylaluminoxane, Et(Ind)2ZrCl2-MAO, initiating systems has been tested. The results obtained with each styrene-cycloalkene couple, except styrene/norbornene, indicate a less effective polymerization process compared to styrene homopolymerization, in agreement with the electronic and steric effects present in each comonomer. The electronic I+ effects of substituent groups, depending on their placement, largely improve the polymerization process, while bulky groups on or near the vinyl carbon double bond of styrene decrease its effectiveness. The present study shows that the copolymers obtained are amorphous and their composition showed a lower abundance of comonomer units with respect to the initial feed. For comparison, the results of the copolymerization of styrene/(1-octadecene) using the same initiator system and polymerization process are included, a polymerization that indicates a more reactive process, and as the proportion of octadecene in the initial feed increases, it showed a crystalline fusion temperature as well as a Tg in the styrene region which can be attributed to the formation of block styrene/octadecene copolymers. 相似文献
155.
Numerous directional medium access control (DMAC) protocols have been developed to enhance the capacity of ad hoc networks using the underlying advanced physical layer techniques, such as beam-forming, multiuser detection (MUD), and multiple-input–multiple-output (MIMO). In this paper, we propose an innovative fully distributed DMAC protocol that cooperatively makes use of polarization diversity in low-mobility urban/suburban outdoor wireless ad hoc network environment. In the proposed cooperative polarization DMAC protocol (CPDMAC), each node directionally senses on both vertical and horizontal polarizations and dynamically adapts polarization that minimizes overall interference in the ad hoc network. Analysis is performed to establish relationship between vertically and horizontally polarized nodes in the network. Further, a theoretical lower bound is derived for probability of successful transmission to show capacity improvement as a function of cross polarization ratio (CPR). Simulation results confirm from 2% up to 400% improvement in average node throughput at data rate of 1.95 Mbps when compared to the traditional DMAC protocol. Moreover, our study clearly shows that the average throughput difference increases with increasing node density when compared to the traditional DMAC protocol. 相似文献
156.
Phenolic characterization and geographical classification of commercial Arbequina extra-virgin olive oils produced in southern Catalonia 总被引:1,自引:0,他引:1
Abdelhakim Bakhouche Jesús Lozano-Sánchez Raúl Beltrán-Debón Jorge Joven Antonio Segura-Carretero Alberto Fernández-Gutiérrez 《Food research international (Ottawa, Ont.)》2013,50(1):401-408
The aim of this work was to characterize Arbequina extra-virgin olive oils (EVOOs) from different locations in southern Catalonia (Spain) in terms of their phenolic profile, to show the classification of oil samples with respect to geographical area. The phenolic compounds present in 32 olive-oil samples were analyzed by a rapid and effective HPLC–ESI-TOF/MS method, and 18 phenolic compounds belonging to different phenolic types were identified. The results showed no qualitative differences in the phenolic fractions among EVOO from different geographical region. However, quantitative differences were observed in a wide number of phenolic compounds. In all olive-oil samples studied, secoiridoids were the most abundant, followed by lignans, phenolic alcohols, and flavonoids, respectively. Multivariate data were analysed by canonical discriminant analyses. Seventeen variables were used without a variable reduction step. Phenolic content of extra-virgin olive oils was found to depend highly on geographical area. 相似文献
157.
Comparative studies on major nutritional components of black waxy rice with giant embryos and its rice bran 总被引:1,自引:0,他引:1
Kim Jun Young Seo Woo Duck Park Dong-Soo Jang Ki Chang Choi Kyung-Jin Kim Sang-Yeol Oh Seong-Hwan Ra Ji-Eun Yi Gihwan Park Soo-Kwon Hwang Un-Ha Song You-Chun Park Bo-Ram Park Mi-Jin Kang Hang-Won Nam Min-Hee Han Sang-Ik 《Food science and biotechnology》2013,22(1):121-128
The concentration of nutrients in brown rice is mainly associated with embryo size. Various beneficial components have been purified from rice bran. Recently developed black waxy rice with a giant embryo (‘Milyang 263’, BGE), which is the ge t mutant of the GE gene, was selected and analyzed to produce high quality nutritional components. γ-Aminobutyric acid (GABA) content in BGE rice bran, one of the most important nutritional compounds in rice, showed a 10.6-fold increase (2.66±0.48 mg/g) compared to that of BGE brown rice (0.25±0.01 mg/g). In addition, brown rice and BGE rice bran showed enriched amylopectin (94.5±0.5 and 97.0±0.0%) and bioactive anthocyanin [Cy-3-G: 75.15±4.18 (brown rice), 82.97±0.81 (rice bran) and Pn-3-G: 1.52±0.50 (brown rice), 4.33±0.20 (rice bran); mg/100 g] contents. These results suggest that BGE rice bran can be used as an excellent raw material to efficiently produce high quality essential amino acids, cyanidin-3 glycoside-enriched anthocyanins, and GABA. 相似文献
158.
To improve the tensile bond strength of denim bonding agents, the adhesion between denim and MMA resin was investigated by applying initiator systems containing 1-cyclohexyl-5-ethyl barbituric acid (CEB), copper acetyl acetonate (CAA), quaternary ammonium chloride (QAC). cupric ion, with the addition of TEGDMA, and pretreatment solution for denim, and an HEMA primer. The effects of a cross-linking agent on barbituric acid-initiated denim bonding resin were examined by measuring degree of conversion, molecular weight, hardness of bonding resin, and tensile bond strengths. 相似文献
159.
Aranda PR Gil RA Moyano S De Vito I Martinez LD 《Journal of hazardous materials》2009,161(2-3):1399-1403
The heavy metal mercury (Hg) is a neurotoxin known to have a serious health impact even at relatively low concentrations. A slurry method was developed for the sensitive and precise determination of mercury in human serum blood samples by cold vapor generation coupled to atomic fluorescence spectrometry (CV-AFS). All variables related to the slurry formation were studied. The optimal hydrochloric concentration and tin(II) chloride concentration for CV generation were evaluated. Calibration within the range 0.1-10 microg L(-1) Hg was performed with the standard addition method, and compared with an external calibration. Additionally, the reliability of the results obtained was evaluated by analyzing mercury in the same samples, but submitted to microwave-assisted digestion method. The limit of detection was calculated as 25 ng L(-1) and the relative standard deviation was 3.9% at levels around of 0.4 microg L(-1)Hg. 相似文献
160.
Luis Juana Raúl Sánchez Leonor Rodríguez-Sinobas Francisco Laguna 《Canadian Metallurgical Quarterly》2009,135(2):186-199
This technical paper presents analytical expressions to estimate the probability function of head losses in any path of an on-demand branched irrigation network. They are developed for estimating the probability of pressure deficit of a given magnitude at any hydrant. They are also useful for examining the probability of a power deficit at a pumping station designed to guarantee service to a hydrant, as well as the head characteristic curve of the distribution system linked to a definite probability. All this quantified information is useful for decision making on network design and performance. The probabilities calculated with the developed expressions can be taken as complementary or alternative concepts to Clément’s classical design flow method, which is taken here as a benchmark for comparisons. Illustrative examples of network designs are presented to validate the proposed expressions. The least cost design solutions using Clément’s design flows are compared with design solutions here obtained to get the same probability of pressure deficit at the most unfavorable hydrants. The new solutions are less expensive because the flow constraint can be avoided. 相似文献