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51.
Journal of Plant Diseases and Protection - Chestnut is an important crop in Portugal, representing an important source of revenue for mountain regions in this country. However, it has been strongly...  相似文献   
52.
Journal of Plant Diseases and Protection - Silicon is considered a beneficial nutrient for agricultural crops by conferred protection against diseases. The antifungal effect of the phenolic...  相似文献   
53.
54.
Mecardonia tenella is an herbaceous plant widely distributed in the temperate region of South America. Both plant architecture and flower size are characteristics that can be improved to become a viable new ornamental plant. Chromosome doubling by the use of agents such as colchicine is an available methodology to this end. Nodal segments from in vitro grown plants of M. tenella were submerged in the following doses of colchicine in 1% (v/v) dimethyl-sulfoxide (DMSO) solution (%, v/v): 0.0, 0.001 and 0.01 (24 and 48 h). The DNA content of the regenerated plants was measured by flow cytometer. A total of 68 tetraploid plants were detected out of 126 colchicine treated plants. The flowers and leaves of the tetraploid plants were bigger compared to those from the wild diploid type (control). Under field conditions, the selected tetraploid plants showed a more compact shape than the control plants.  相似文献   
55.
Transforming growth factor-beta (TGF-beta) superfamily members regulate a plethora of developmental processes, and disruption of their activity has been implicated in a variety of human diseases ranging from cancer to chondrodysplasias and pulmonary hypertension. Intense investigations have revealed that SMAD proteins constitute the basic components of the core intracellular signaling cascade and that SMADs function by carrying signals from the cell surface directly to the nucleus. Recent insights have revealed how SMAD proteins themselves are regulated and how appropriate subcellular localization of SMADs and TGF-beta transmembrane receptors is controlled. Current research efforts investigating the contribution of SMAD-independent pathways promise to reveal advances to enhance our understanding of the signaling cascade.  相似文献   
56.
In this paper, accelerated solvent extraction (ASE) for the analysis of ochratoxin A (OTA) is applied for the first time. Optimization of the method is given for the extraction of OTA from rice samples. Several parameters such as type of solvent, temperature, pressure, static time, and cell size were investigated thoroughly to find the optimal extraction conditions. The optimum ASE operating conditions were methanol as extraction solvent, 1500 psi, 40 degrees C, 5 min of static time, 50% flush volume, 60 s of purge, 1 cycle, and 11 mL cell size. The total extraction time was approximately 15 min. OTA was determined by liquid chromatography coupled with a fluorescence detector and confirmed by methyl ester derivatization. The analytical performance of the method was monitored with quality control parameters. Finally, the optimized method was used to evaluate 12 rice samples, 1 of which was positive with an OTA content of 4.17 ng/g. The proposed method offers the possibility of a fast and simple process to obtain a quantitative extraction of OTA.  相似文献   
57.
Landscape Ecology - Validation of models of Land Use and Cover Change often involves comparing maps of simulated and reference change. The interpretation of differences between simulated and...  相似文献   
58.
Osteosarcoma is the most common paediatric primary bone malignancy. The major cause of death in osteosarcoma is drug‐resistant pulmonary metastasis. Previous studies have shown that thioredoxin reductase 2 is a driver of metastasis in osteosarcoma and can be inhibited by auranofin (AF). Moreover, studies have shown that AF significantly reduces pulmonary metastases in xenotransplant models. Here, we describe a phase I/II study of AF in canine osteosarcoma, a well‐recognized spontaneous model of human osteosarcoma. We performed a single‐arm multicentre pilot study of AF in combination with standard of care (SOC) (amputation + carboplatin). We recruited 40 dogs to the trial and used a historical SOC‐only control group (n = 26). Dogs >15 kg received 9 mg AF q3d PO and dogs <15 kg received 6 mg q3d. Follow‐up occurred over at least a 3‐year period. Auranofin plus SOC improved overall survival (OS) (P = .036) in all dogs treated. The improved outcome was attributable entirely to improved OS in male dogs (P = .009). At the time of writing, 10 dogs (25%) survive without measurable disease in the treatment group with survival times ranging between 806 and 1525 days. Our study shows that AF improves OS in male dogs when combined with SOC. Our findings have translational relevance for the management of canine and human osteosarcoma. Our data justify a larger multicentre phase 2 trial in dogs and a phase I/II trial in human patients with refractory disease at the time of initial surgery.  相似文献   
59.
Lake Yuriria, located in the heavily populated and polluted Mexican Central Plateau, receives domestic sewage, industrial effluents, and municipal wastewaters that are still directly discharged without treatment into the tributaries and the lake. Pollutants in water and sediments include heavy metals, aromatic hydrocarbons, and organochlorine pesticides. Activities of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), as well as Na+/K+-adenosine triphosphatase (Na+/K+-ATPase) activity, and lipid peroxidation (LPO) were evaluated in the livers of the fish Goodea atripinnis after 96 h of exposure to water collected in March and June 2005 from three sites: Y (limnetic zone), L (Lerma tributary), and C (la Cinta tributary). Physical and chemical parameters of the lake water were also analyzed. Increases in CAT activity and LPO levels at all three sites were detected compared with control fish (P < 0.05), while GPx and SOD activities decreased significantly (P < 0.05). Na+/K+-ATPase activities were similar to the control in fish exposed to limnetic water from both March and June but were higher than control at the two tributary sites in March (P < 0.05); fish exposed to water from the Lerma tributary in June exhibited lower Na+/K+-ATPase than the control (P < 0.05). During March, CAT and Na+/K+-ATPase activities were increasing more than in June in Y and L, respectively, while in June, SOD and GPx were depleted more than March in L and Y and L, respectively. Despite the antioxidant defenses of the fish liver, exposure to all water samples from Lake Yuriria exerted alterations in hepatic LPO levels, antioxidant enzymes, and Na+/K+-ATPase activities that could substantially impair the mechanisms of fish defenses against oxidative stress.  相似文献   
60.
A new natural spiro compound 3,4-dehydrotheaspirone and the known arctiol [1β,6α-dihydroxy-4(14)-eudesmene] were isolated from Juniperus brevifolia. Arctiol is reported for the first time in the Juniperus genus. Their structures were established by 1D, and 2D NMR and MS spectra. Antimicrobial and cytotoxic activities of 1 and several secondary metabolites ,,,,,,,,, previously isolated by our group from J. brevifolia were evaluated and some SAR has been established. The 18-hydroxydehydroabietane (4) displayed great antiproliferative activity against cancer cell lines tested, namely HeLa, A-549 and MCF-7. Compound 4 also presented a significant bactericidal effect against Bacillus cereus at different concentrations tested.  相似文献   
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