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151.
The analysis of histological sections has long been a valuable tool in the pathological studies. The interpretation of tissue conditions, however, relies directly on visual evaluation of tissue slides, which may be difficult to interpret because of poor contrast or poor color differentiation. The Chromatic Contrast Visualization System (CCV) combines an optical microscope with electronically controlled light-emitting diodes (LEDs) in order to generate adjustable intensities of RGB channels for sample illumination. While most image enhancement techniques rely on software post-processing of an image acquired under standard illumination conditions, CCV produces real-time variations in the color composition of the light source itself. The possibility of covering the entire RGB chromatic range, combined with the optical properties of the different tissues, allows for a substantial enhancement in image details. Traditional image acquisition methods do not exploit these visual enhancements which results in poorer visual distinction among tissue structures. Photodynamic therapy (PDT) procedures are of increasing interest in the treatment of several forms of cancer. This study uses histological slides of rat liver samples that were induced to necrosis after being exposed to PDT. Results show that visualization of tissue structures could be improved by changing colors and intensities of the microscope light source. PDT-necrosed tissue samples are better differentiated when illuminated with different color wavelengths, leading to an improved differentiation of cells in the necrosis area. Due to the potential benefits it can bring to interpretation and diagnosis, further research in this field could make CCV an attractive technique for medical applications. 相似文献
152.
R Baumgart M Kettler C Zeiler A Betz L Schweiberer 《Canadian Metallurgical Quarterly》1997,100(10):797-804
Corrective measures on the bone undertaken after the fusion of epiphyses are only possible through an initial break in its continuity. This paper deals with the different methods of osteotomy available to the orthopaedic or trauma surgeon. After introducing the terminology of the so-called "osteotomy", the vascularity of the bone, special features of the various osteotomy site, the different indications, and particular details of the operative procedures are discussed. Special emphasis is placed on minimally invasive techniques and osteotomies in the framework of callus distraction. In addition to established procedures a new sawing technique for the Küntscher's closed osteotomy is described. 相似文献
153.
Regina Klimova Ekaterina Momotyuk Natalia Demidova Natalia Fedorova Yana Chernoryzh 《Fullerenes, Nanotubes and Carbon Nanostructures》2020,28(6):487-499
AbstractFullerene C60 is known as a promising therapeutic agent due to its antioxidant, anti-inflammatory and other properties, along with the lack of noticeable toxicity. In this article, we describe antiviral properties of aqueous fullerene C60 dispersion (ndC60) produced by biocompatible diafiltration technology and C60 amino derivatives against Herpes simplex virus type 1 (HSV-1) and Human cytomegalovirus (HCMV) infections. Their activity in vitro was evaluated by a plaque reduction assay using Vero and HF cells in pre- and post-treatment modes. Therapeutic efficacy of dnC60 and C60 derivatives was studied in DBA mice using cutaneous model of HSV-1 infection. Data obtained indicated low cytotoxicity of all used compounds for both cell lines (CC50 > 1?mg/ml). The antiviral activity of dnC60 in most tests exceeded the activity of both C60 amino adducts and acyclovir (ACV), and it demonstrated significant therapeutic effect against HSV-1 skin infection in mice. 相似文献
154.
Provin Ana Paula Cubas Anelise Leal Vieira Dutra Ana Regina de Aguiar Schulte Neide Köhler 《Clean Technologies and Environmental Policy》2021,23(10):2813-2825
Clean Technologies and Environmental Policy - The textile industry is one of the most complex sectors in relation to environmental degradation, both with regard to the materials used from petroleum... 相似文献
155.
T Dresbach ME Burns V O'Connor WM DeBello H Betz GJ Augustine 《Canadian Metallurgical Quarterly》1998,18(8):2923-2932
Sec1-related proteins are essential for membrane fusion at distinct stages of the constitutive and regulated secretory pathways in eukaryotic cells. Studies of neuronal isoforms of the Sec1 protein family have yielded evidence for both positive and negative regulatory functions of these proteins in neurotransmitter release. Here, we have identified a squid neuronal homolog (s-Sec1) of Sec1 proteins and examined its function in neurotransmitter release at the squid giant synapse. Microinjection of s-Sec1 into the presynaptic terminal of the giant synapse inhibited evoked neurotransmitter release, but this effect was prevented by coinjecting the cytoplasmic domain of squid syntaxin (s-syntaxin), one of the binding partners of s-Sec1. A 24 amino acid peptide fragment of s-Sec1, which inhibited the binding of s-Sec1 to s-syntaxin in vitro, completely blocked release, suggesting an essential function of the s-Sec1/s-syntaxin interaction in transmitter release. Electron microscopy showed that injection of s-Sec1 did not change the spatial distribution of synaptic vesicles at presynaptic release sites ("active zones"), whereas the inhibitory peptide increased the number of docked vesicles. These distinct morphological effects lead us to conclude that Sec1 proteins function at different stages of synaptic vesicle exocytosis, and that an interaction of s-Sec1 with syntaxin-at a stage blocked by the peptide-is necessary for docked vesicles to fuse. 相似文献
156.
Emmanuel T. D. Mensah Hederick R. Dankwa Torben L. Lauridsen Dennis Trolle Ruby Asmah Benjamin B. Campion Regina Edziyie Villy Christensen 《Lakes & Reservoirs: Research and Management》2019,24(3):246-254
A mass balance model of trophic interactions among ten key functional producer and consumer groups in Lake Volta was constructed using the Ecopath model to study the energy flows and species interactions in the lake. The present study was based on secondary and primary data on fish catch, diet composition, phytoplankton and zooplankton biomasses, collected in 2015 and 2016. Additional information on growth parameters of major species required for balancing the Ecopath model was obtained from sampling and FishBase. The functional groups were detritus, phytoplankton, zooplankton, benthos, prey fish, Tilapia, Bagrus, Chrysichthys, Alestes and Synodontis species. Four trophic levels were identified in the Lake Volta ecosystem, with the energy flow occurring mainly within the first three trophic levels. The calculated ecotrophic efficiency value of the primary producers (phytoplankton: 0.17; detritus: 0.22) indicated they were least exploited, compared to the secondary producers, zooplankton (0.80) and benthos (0.50). All secondary consumers had ecotrophic efficiency values higher than the primary producers, indicating they are exploited in the ecosystem. The main energy flows in the lake were from phytoplankton and detritus at trophic level I, and Bagrus species, the top predator, at a level of 3.30. The network analysis, illustrating a connectance index of 0.43 and an omnivory index of 0.06, in the lake system indicated the ecosystem is unstable, somewhat immature and still in a developing stage. 相似文献
157.
Regina Zschaler 《European Journal of Lipid Science and Technology》1977,79(3):107-109
Method for the Determination of the Dispersion of Water-Droplets in Water-in-Oil-Emulsion (w/o-Emulsion) We find emulsions of the w/o type for instance in margarine and butter. Besides other facts the fine dispersion of the water in microscopical small droplets, which are coated by fat, are of importance. Therefore, it is of interest for the manufacturer that he has an exact idea of the dispersion of the water droplets in his product. We describe the method for the determination of the water dispersion and the preparation of the test material. 相似文献
158.
Anna Wonaschuetz Theresa Haller Eva Sommer Lorenz Witek Hinrich Grothe Regina Hitzenberger 《Aerosol science and technology》2019,53(1):21-28
Steam collection devices collecting aerosol particles into liquid samples are frequently used to analyze water-soluble particulate material. The fate of water-insoluble components is often neglected. In this work, we show that fresh soot particles can be suspended into pure water using a steam collection device, the particle-into-liquid sampler (PILS, Weber et?al. 2001). The overall collection efficiency of freshly generated soot particles was found to be on the order of 20%. This shows that, depending on the analytic technique employed, the presence of insoluble, and/or hydrophobic particles in liquid samples from steam collection cannot be neglected.
Copyright © 2018 The Author(s). Published with license by Taylor & Francis Group, LLC 相似文献
159.
Rossi EA Vendramini RC Carlos IZ de Oliveira MG de Valdez GF 《Archivos latinoamericanos de nutrición》2003,53(1):47-51
This study was undertaken to verify the effect of a daily intake of a new fermented soy milk produced with Enterococcus faecium and Lactobacillus jugurti on the serum lipid levels in normocholesterolemic middle-aged men. The study was randomized, double-blind and placebo-controlled and was performed for a period of 6 weeks. Forty-four normocholesterolemic healthy, male volunteers, aged 40-55 years old were randomly separated in two groups: The F-group received 200 ml of the fermented product daily and the P-group received 200 ml of placebo (chemically fermented). The blood samples were drawn initially and after 3 and 6 weeks and serum values for total cholesterol, HDL-cholesterol and triglyceride were determined. The LDL-cholesterol value was estimated. No significant changes in the fermented group (F) were observed for total cholesterol, LDL-cholesterol or triglyceride levels, while the HDL-cholesterol level was significantly higher (p < or = 0.05) after 6 weeks. The total cholesterol and LDL-cholesterol levels were significantly higher (p < or = 0.05) in the placebo group (P), but no changes were found for the HDL-cholesterol and triglyceride levels during the experimental period. In conclusion, the intake of 200 ml/day of the fermented soy milk, produced with E. faecium and L. jugurti, for 6 weeks, did not affect the serum total cholesterol and LDL-cholesterol, and led an increase of 10% in the HDL-cholesterol level. 相似文献
160.
Neiva Maria de Almeida Maria Regina Bueno Franco 《Journal of the American Oil Chemists' Society》2006,83(8):707-711
This research aimed to quantify the methyl esters of linoleic (LA), γ-linolenic (LNA), arachidonic (AA), eicosapentaenoic
(EPA), and docosahexaenoic (DHA) acids in the muscular tissue and orbital cavity of farmed tambaqui (Colossoma macropomum) and in those caught in the Brazilian Amazonian Area during two periods. For the farmed fish, the amounts of LA, LNA, AA,
EPA, and DHA found in the muscle were 208.0, 12.4, 57.9, 5.0, and 25.1 mg/g, respectively. The amounts of these FA in the
orbital cavity were 103.4, 6.6, 20.0, 4.4, and 8.1 mg/g for LA, LNA, AA, EPA, and DHA, respectively. For the fish caught during
the flood period, the LA, LNA, AA, EPA, and DHA levels were 297.3, 50.7, 32.3, 3.8, and 14.1 mg/g in the muscle and in the
orbital cavity were 259.7, 40.3, 10.8, 5.5, and 9.3 mg/g, respectively. For the fish captured in the dry season the levels
of LA, LNA, AA, EPA and DHA in the muscle were 262.0, 48.0, 157.6, 9.3, and 40.2 mg/g and in the orbital cavity were 102.5,
15.7, 24.6, 7.0, and 8.9 mg/g. According to their contents of AA, EPA, and DHA, tambaqui captured in the dry season can be
considered as a rich source of EFA. The adipose tissue of the orbital cavity did not show sufficiently high EPA and DHA contents
to classify it as a better source of FA than the muscle. 相似文献