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81.
Irene Flickinger Barbara C Rütgen Wilhelm Gerner Ivana Calice Alexander Tichy Armin Saalmüller Miriam Kleiter 《Journal of veterinary science (Suw?n-si, Korea)》2013,14(2):207-214
To evaluate radiosensitivity and the effects of radiation on the expression of vascular endothelial growth factor (VEGF) and VEGF receptors in the canine oral melanoma cell line, TLM 1, cells were irradiated with doses of 0, 2, 4, 6, 8 and 10 Gray (Gy). Survival rates were then determined by a MTT assay, while vascular endothelial growth factor receptor (VEGFR)-1 and -2 expression was measured by flow cytometry and apoptotic cell death rates were investigated using an Annexin assay. Additionally, a commercially available canine VEGF ELISA kit was used to measure VEGF. Radiosensitivity was detected in TLM 1 cells, and mitotic and apoptotic cell death was found to occur in a radiation dose dependent manner. VEGF was secreted constitutively and significant up-regulation was observed in the 8 and 10 Gy irradiated cells. In addition, a minor portion of TLM 1 cells expressed vascular endothelial growth factor receptor (VEGFR)-1 intracellularly. VEGFR-2 was detected in the cytoplasm and was down-regulated following radiation with increasing dosages. In TLM 1 cells, apoptosis plays an important role in radiation induced cell death. It has also been suggested that the significantly higher VEGF production in the 8 and 10 Gy group could lead to tumour resistance. 相似文献
82.
Bronshtein A Chuang JC Van Emon JM Altstein M 《Journal of agricultural and food chemistry》2012,60(17):4235-4242
Development of a multianalyte enzyme-linked immunosorbent assay (ELISA) for detection of permethrin and aroclors 1248 or 1254 and implementation of the assay for analysis of soil/sediment samples are described. The feasibility of using the multianalyte ELISA to monitor aroclors 1254 and permethrin simultaneously was tested with permethrin and aroclor standards and with aroclor- and permethrin-containing soil/sediment and house dust samples. Comparison of the I?? and I?? values of the multianalyte with those of a single-analyte assay revealed similar results, and multianalyte ELISA determination of analyte amounts in soil/sediment dust samples yielded similar results to those of a single-analyte assay. A single-analyte assay of permethrin content in permethrin-containing dust samples showed that the ELISA can determine the analyte accurately in samples with dust matrix contents ranging from 6.25 to 100 mg as indicated by the good correlation between the results of the immunoassay and those of the gas chromatography analysis. 相似文献
83.
Ivones Hernndez-Balmaseda Idania Rodeiro Guerra Ken Declerck Jos Alfredo Herrera Isidrn Claudina Prez-Novo Guy Van Camp Olivier De Wever Kethia Gonzlez Mayrel Labrada Adriana Carr Geovanni Dantas-Cassali Diego Carlos dos Reis Livan Delgado-Roche Roberto Rafael Nuez Ren Delgado-Hernndez Miguel David Fernndez Miriam T. Paz-Lopes Wim Vanden Berghe 《Marine drugs》2021,19(2)
84.
Marcelo F. Tognelli Miriam Fernández Pablo A. Marquet 《Biological conservation》2009,142(12):3147-1050
The growing concern about the profound influence of human activities on marine ecosystems has been the driving force behind the creation of marine reserves in the last few decades. With almost 4200 km of coastline, Chile has not been the exception to this trend. A set of conservation priority sites has recently been proposed by the Chilean government to expand the current marine reserve network. In this study, we used the most comprehensive information currently available on the distribution of 2513 marine species in Chile to assess the efficiency of the existing system of marine protected areas (MPA) and the conservation priority sites identified by the government. Additionally, we evaluated the vulnerability of the reserve network selected with respect to threatening human activities. Our results show that both the existing protected areas and the proposed priority sites are relatively effective at protecting Chilean marine biodiversity. However, the majority of the species that are not represented within the existing or projected MPA network have very restricted distributions and are, therefore, of high conservation concern. To cover all species requires a network of 35 MPAs (46% of the total number of planning units). Many of the sites identified as irreplaceable present conflict with one or more human activities, particularly in the central region of the country. This study emphasizes the need for a systematic conservation planning approach to maximize the representation of species and prioritize those areas where conflicts between marine biodiversity conservation and human activities may occur. 相似文献
85.
86.
Villagrasa M Guillamón M Eljarrat E Barceló D 《Journal of agricultural and food chemistry》2006,54(4):1001-1008
A new analytical method based on the use of pressurized liquid extraction (PLE) followed by solid-phase extraction with LiChrolut RP C18 cartridges was evaluated for the sample preparation, extraction, and cleanup of eight naturally occurring benzoxazinone derivatives, 2-beta-D-glucopyranosyloxy-4-hydroxy-1,4-benzoxazin-3-one, 2-beta-D-glucopyranosyloxy-4-hydroxy-7-methoxy-1,4-benzoxazin-3-one, 2,4-dihydroxy-1,4-benzoxazin-3-one (DIBOA), 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one, 2-hydroxy-1,4-benzoxazin-3-one, 2-hydroxy-7-methoxy-1,4-benzoxazin-3-one, benzoxazolin-2-one, and 6-methoxybenzoxazolin-2-one in plant samples. Afterward, liquid chromatography-electrospray mass spectrometry, using the selected ion monitoring mode and internal standard (2-MeO-DIBOA, indoxyl-beta-D-glucoside, and quercetin-3-O-rutinoside) quantification method was performed. This paper demonstrates the effectiveness of the PLE method, in conjunction with sensitive and specific mass spectrometric detection, for the quantitative recovery of compounds of the benzoxazinone class from plants. The recoveries of the analytes ranged from 66 to 110% with coefficients of variation ranging from 1 to 14%. This method gave detection limits between 1 and 27 microg/g. The method was applied to foliage and roots of three different wheat cultivars, and the analytes were detected in the range of 11-3261 microg/g of dry weight. 相似文献
87.
Shan He Yichen Guo Tehila Stone Noah Davis Dongwhan Kim Taejin Kim Miriam Rafailovich 《Journal of Wood Science》2017,63(2):154-160
A wood-plastic combination (WPC) was created via in situ polymerization of the l-lactide monomer (3S)-cis-3,6-dimethyl-1,4-dioxane-2,5-dione. Commercial poplar boards (Liriodendron tulipifera) were impregnated with the flame retardant chemical resorcinol bis(diphenyl phosphate)(RDP). These samples were then soaked in a solution of the monomer and deionized water with sulfuric acid 5% wt/wood as a catalyst for polymerization. The wood and solution were placed in a vacuum oven for impregnation and polymerization of the monomers. The wood RDP combination was not flame retardant and had an Izod impact strength that was slightly smaller than neat wood sample. Addition of lactide monomer tripled the Izod impact strength relative to wood, and scanning electron microscope (SEM) images indicated that a polymerized coating had formed which reinforced the porous wood structure. Addition of all three components produced a synergy. The Izod impact strength of the material was nearly 14 times greater and the WPC was flame retardant surpassing the stringent UL-94-V0 requirement. 相似文献
88.
Kerkmann A Ganter M Frase R Ostmeier M Hewicker-Trautwein M Distl O 《Berliner und Münchener tier?rztliche Wochenschrift》2010,123(9-10):413-421
In three flocks, 13 pure- and 1 crossbred German black headed mutton lambs were ascertained which had clinical signs of epidermolysis bullosa (EB). The three farmers reported of further 20 affected lambs with similar signs in their flocks in the past lambing seasons. The affected lambs were progeny of six rams and 17 ewes. Two rams and six ewes with affected offspring from two farms were used for a breeding trial. In the course of these experimental matings, 21 lambs were born, six of which were affected by EB. All lambs born in this trial underwent clinical and haematological examination and all the affected lambs had to be euthanised due to severe and progressing clinical symptoms. Clinical examinations in 20 affected lambs revealed shedding of claw horn, erosions and ulcers of skin and mucous membranes. Histopathology showed subepidermal splitting and blistering with intact basal keratinocytes. These findings together with the premature death of affected lambs within the first two months of life made a Herlitz type of junctional EB most likely. The results of the test matings demonstrated the genetic transmission and indicated an autosomal recessive mode of inheritance for this lethal condition. 相似文献
89.
90.
Edge effects are suggested to have great impact on the persistence of species in fragmented landscapes. We tested edge avoidance by forest understory passerines in the Brazilian Atlantic Rainforest and also compared their mobility and movement patterns in contiguous and fragmented landscapes to assess whether movements would increase in the fragmented landscape. Between 2003 and 2005, 96 Chiroxiphia caudata, 38 Pyriglena leucoptera and 27 Sclerurus scansor were radio-tracked. The most strictly forest species C. caudata and S. scansor avoided forest edges, while P. leucoptera showed affinities for the edge. Both sensitive species showed larger mean step length and maximal observed daily distance in the fragmented forest versus the unfragmented forest. P. leucoptera did not show any significant difference. There were no significant differences in proportional daily home range use for any of the three species. Our results suggested that fragmentation and the consequent increase in edge areas do influence movement behavior of sensitive forest understory birds that avoided the use of edges and increased the speed and distance they covered daily. For the most restricted forest species, it would be advisable to protect larger patches of forest instead of many small or medium fragments connected by narrow corridors. However, by comparing our data with that obtained earlier, we concluded that movement behavior of resident birds differs from that of dispersing birds and might not allow to infer functional connectivity or landscape-scale sensitivity to fragmentation; a fact that should be taken into consideration when suggesting conservation strategies. 相似文献