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排序方式: 共有713条查询结果,搜索用时 15 毫秒
1.
Carlos Garcia-Padilla Estefanía Lozano-Velasco María del Mar Muoz-Gallardo Juan Manuel Castillo-Casas Sheila Cao-Carrillo Francisco Jos Martínez-Amaro Virginio García-Lpez Amelia Arnega Diego Franco Virginio García-Martínez Carmen Lpez-Snchez 《International journal of molecular sciences》2022,23(15)
Various treatments based on drug administration and radiotherapy have been devoted to preventing, palliating, and defeating cancer, showing high efficiency against the progression of this disease. Recently, in this process, malignant cells have been found which are capable of triggering specific molecular mechanisms against current treatments, with negative consequences in the prognosis of the disease. It is therefore fundamental to understand the underlying mechanisms, including the genes—and their signaling pathway regulators—involved in the process, in order to fight tumor cells. Long non-coding RNAs, H19 in particular, have been revealed as powerful protective factors in various types of cancer. However, they have also evidenced their oncogenic role in multiple carcinomas, enhancing tumor cell proliferation, migration, and invasion. In this review, we analyze the role of lncRNA H19 impairing chemo and radiotherapy in tumorigenesis, including breast cancer, lung adenocarcinoma, glioma, and colorectal carcinoma. 相似文献
2.
Salima Alem Ta-Ya Chu Shing C. Tse Salem Wakim Jianping Lu Raluca Movileanu Ye Tao Francis Bélanger Denis Désilets Serge Beaupré Mario Leclerc Sheila Rodman David Waller Russell Gaudiana 《Organic Electronics》2011,12(11):1788-1793
We investigated the effect of solvents on the morphology, charge transport and device performance of poly[N-9″-hepta-decanyl-2,7-carbazole-alt-5,5-(4′,7′-di-2-thienyl-2′,1′,3′-benzothiadiazole)] (PCDTBT) and [6,6]-phenyl C71-butyric acid methyl ester (PC70BM) based solar cells. To carry out this investigation, chloroform and 1,2-dichlorobenzene were chosen as good solvents of the two compounds. Films prepared with chloroform exhibit larger domains than those prepared with 1,2-dichlorobenzene and their size increases with the amount of PC70BM. Fine tuning of the domain size was realized by using a solvent of mixed chloroform and 1,2-dichlorobenzene. At a mixing ratio of 50%:50%, a power conversion efficiency of 6.1% was achieved on PCDTBT:PC70BM (1:3) devices with an active area of 1 cm2, under air mass 1.5 global (AM 1.5 G) irradiation at 100 mW/cm2. 相似文献
3.
OH Perez R Aznar LM Ballesteros JD Mendez A Rosado 《Canadian Metallurgical Quarterly》1976,14(4):421-433
Ribonucleic acid (RNA) metabolism of the normal and copper-treated ( Cu-T200 IUD) human endometrium was investigated. The relative concentration of total, messenger, ribosomal and transfer RNA was measured in normal and Cu-treated endometrium using the technique of affinity chromatography in polysepharose. The transition from the proli ferative to the secretory endometrium in normal women was accompanied by significant increases (p less than .05) in total RNA, messenger RNA and in ribosomal RNA. The relative proportions of bound and free messenger RNA were also modified by endometrial maturation changing from 70% bound messenger RNA in the proliferative to 83% in the secretory phase. Cu-T200 Cu release appeared to particularly affect RNA metabolism in the secretory phase. During the proliferative phase only the concentration of transfer RNA and the proportion of bound to free messenger RNA were modified by the Cu-T200. The Cu-T200 induced significant decreases (p less than .01 and p less than .05) in all RNA parameters, with the exception of the RNA/deoxyribonucleic acid ratio. 相似文献
4.
Irene R. Grant Antonio C.G. Foddai James C. Tarrant Brenna Kunkel Faye A. Hartmann Sheila McGuirk Chungyi Hansen Adel M. Talaat Michael T. Collins 《Journal of dairy science》2017,100(12):9723-9735
When advising farmers on how to control Johne's disease in an infected herd, one of the main recommendations is to avoid feeding waste milk to calves and instead feed calf milk replacer (CMR). This advice is based on the assumption that CMR is free of viable Mycobacterium avium ssp. paratuberculosis (MAP) cells, an assumption that has not previously been challenged. We tested commercial CMR products (n = 83) obtained from dairy farms around the United States by the peptide-mediated magnetic separation (PMS)-phage assay, PMS followed by liquid culture (PMS-culture), and direct IS900 quantitative PCR (qPCR). Conventional microbiological analyses for total mesophilic bacterial counts, coliforms, Salmonella, coagulase-negative staphylococci, streptococci, nonhemolytic Corynebacterium spp., and Bacillus spp. were also performed to assess the overall microbiological quality of the CMR. Twenty-six (31.3%) of the 83 CMR samples showed evidence of the presence of MAP. Seventeen (20.5%) tested positive for viable MAP by the PMS-phage assay, with plaque counts ranging from 6 to 1,212 pfu/50 mL of reconstituted CMR (average 248.5 pfu/50 mL). Twelve (14.5%) CMR samples tested positive for viable MAP by PMS-culture; isolates from all 12 of these samples were subsequently confirmed by whole-genome sequencing to be different cattle strains of MAP. Seven (8.4%) CMR samples tested positive for MAP DNA by IS900 qPCR. Four CMR samples tested positive by both PMS-based tests and 5 CMR samples tested positive by IS900 qPCR plus one or other of the PMS-based tests, but only one CMR sample tested positive by all 3 MAP detection tests applied. All conventional microbiology results were within current standards for whole milk powders. A significant association existed between higher total bacterial counts and presence of viable MAP indicated by either of the PMS-based assays. This represents the first published report of the isolation of viable MAP from CMR. Our findings raise concerns about the potential ability of MAP to survive manufacture of dried milk-based products. 相似文献
5.
Tara J Fano Sheila M Tyminski Mary A T Flynn 《Revue canadienne de la pratique et de la recherche en diététique》2004,65(2):72-80
To evaluate the impact of the Calgary Health Region Collective Kitchen Program on various Population Health Promotion Model health determinants, data were collected through mail-in questionnaires that examined the members' (n=331) and coordinators' (n=58) perspectives of the program. Seventy-nine members (24%) and 26 coordinators (45%) were included in the study. Three incomplete questionnaires (from prenatal program members) were discarded. Sixty-one percent of members who reported income level and family size (n=61) had incomes below the low-income cut-off. Fifty-eight members (73%) reported improvements in their lives because of the program. Sixty-four members (81%) perceived they learned to feed their families healthier foods. The members reported their fruit and vegetable consumption before and since joining a collective kitchen, and the proportion of those consuming at least five fruit and vegetable servings a day rose from 29% to 47%. The most common reasons for joining this program concerned social interactions and support. Over 90% of the coordinators perceived that they were competent to coordinate a kitchen. The results indicate that the collective kitchens program addresses several health determinants, and may increase members' capacity to attain food security and to achieve improved nutritional health. 相似文献
6.
Barber LB Murphy SF Verplanck PL Sandstrom MW Taylor HE Furlong ET 《Environmental science & technology》2006,40(2):475-486
Identifying the sources and impacts of organic and inorganic contaminants at the watershed scale is a complex challenge because of the multitude of processes occurring in time and space. Investigation of geochemical transformations requires a systematic evaluation of hydrologic, landscape, and anthropogenic factors. The 1160 km2 Boulder Creek Watershed in the Colorado Front Range encompasses a gradient of geology, ecotypes, climate, and urbanization. Streamflow originates primarily as snowmelt and shows substantial annual variation. Water samples were collected along a 70-km transect during spring-runoff and base-flow conditions, and analyzed for major elements, trace elements, bulk organics, organic wastewater contaminants (OWCs), and pesticides. Major-element and trace-element concentrations were low in the headwaters, increased through the urban corridor, and had a step increase downstream from the first major wastewater treatment plant (WWTP). Boron, gadolinium, and lithium were useful inorganic tracers of anthropogenic inputs. Effluent from the WWTP accounted for as much as 75% of the flow in Boulder Creek and was the largest chemical input. Under both hydrological conditions, OWCs and pesticides were detected in Boulder Creek downstream from the WWTP outfall as well as in the headwater region, and loads of anthropogenic-derived contaminants increased as basin population density increased. This report documents a suite of potential endocrine-disrupting chemicals in a reach of stream with native fish populations showing indication of endocrine disruption. 相似文献
7.
8.
Sheila Romo-Sánchez María Arévalo-Villena Esteban García Romero Héctor L. Ramirez Ana Briones Pérez 《Food and Bioprocess Technology》2014,7(5):1381-1392
Enzyme immobilization is becoming more widely practised in biotechnology because of the advantages that this method brings. In this study, commercial β-glucosidase for aroma released in winemaking was immobilized on diverse supports (alginate–chitin, chitosan–chitin) by using different methods. It was found that the most appropriate matrix was chitosan by adsorption and reticulation. The optimal immobilization conditions were pH 3.5, immobilization time 120 min, and concentration of cross-linker glutaraldehyde 0.25 %. Stability of the immobilized enzymes was assessed, which revealed a number of advantages, such as a lower enzyme dose required for immobilization (367 times lower than the free enzyme dose recommended by the manufacturer), high stability over time, and reusability. In vitro studies of cellobiose and in vivo studies of wine and aroma precursors isolated from grape must yielded similar outcomes with respect to enzyme hydrolysis of free and immobilized proteins. 相似文献
9.
10.
Laura Vicente Nigel Deighton Sheila M. Glidewell José A. Empis Bernard A. Goodman 《European Food Research and Technology》1995,200(1):44-46
The generation of free radical intermediates as a result of the oxidative degradation of lipid molecules during the heating of grape seed oil has been established by a combination of “spin trapping” and electron paramagnetic resonance spectroscopy. The effects of temperature on the rates of formation and decomposition of the adduct with the spin trapN-t-butyl-α-phenylnitrone (PBN) have been investigated over the temperature range 105–180°C. The results show that PBN can be used for studies of free radical processes in oils in situ in the spectrometer cavity at temperatures up to 180°C. 相似文献