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排序方式: 共有211条查询结果,搜索用时 15 毫秒
21.
Alejandro M. S. Mayer Abimael D. Rodríguez Orazio Taglialatela-Scafati Nobuhiro Fusetani 《Marine drugs》2013,11(7):2510-2573
The peer-reviewed marine pharmacology literature from 2009 to 2011 is presented in this review, following the format used in the 1998–2008 reviews of this series. The pharmacology of structurally-characterized compounds isolated from marine animals, algae, fungi and bacteria is discussed in a comprehensive manner. Antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral pharmacological activities were reported for 102 marine natural products. Additionally, 60 marine compounds were observed to affect the immune and nervous system as well as possess antidiabetic and anti-inflammatory effects. Finally, 68 marine metabolites were shown to interact with a variety of receptors and molecular targets, and thus will probably contribute to multiple pharmacological classes upon further mechanism of action studies. Marine pharmacology during 2009–2011 remained a global enterprise, with researchers from 35 countries, and the United States, contributing to the preclinical pharmacology of 262 marine compounds which are part of the preclinical pharmaceutical pipeline. Continued pharmacological research with marine natural products will contribute to enhance the marine pharmaceutical clinical pipeline, which in 2013 consisted of 17 marine natural products, analogs or derivatives targeting a limited number of disease categories. 相似文献
22.
Tsutsumi T Amakura Y Ashieda K Okuyama A Tanioka Y Sakata K Kobayashi Y Sasaki K Maitani T 《Journal of agricultural and food chemistry》2008,56(9):2867-2874
The efficacy of a combination of two enzyme-linked immunosorbent assay (ELISA) kits was examined for screening the toxic equivalent (TEQ) concentrations of dioxins in retail fish. The coplanar PCB-EIA system, which is a competitive immunoassay specific for polychlorinated biphenyl (PCB) 118, was tested as a screening method for mono- ortho PCBs. The Ah immunoassay (Ah-I), which is an ELISA-based aryl hydrocarbon receptor binding assay, was analyzed for its screening ability for non- ortho PCBs, polychlorinated dibenzo- p-dioxins (PCDDs), and dibenzofurans (PCDFs). Dilution and recovery tests using purified fish extracts revealed no major interference of the matrix in the PCB-EIA and suggested that the matrix effect was minimized in the Ah-I. Finally, the results for the fish samples ( n = 20) showed a strong correlation between this method and high-resolution gas chromatography coupled to high-resolution mass spectrometry for the determination of the TEQ concentrations of mono- ortho PCBs ( r = 0.99) and non- ortho PCBs and PCDD/Fs ( r = 0.97). These data indicate that our method is suitable for screening retail fish to determine the TEQ concentrations of dioxins. 相似文献
23.
以日本横滨市国道两侧绿地土壤和横滨国立大学校内绿地土壤为研究区,采用连续浸提-ICP法分析了横滨市土壤环境中表层(0~5cm)和5~20cm处的Pb元素的水溶性、离子态、碳酸盐结合态、铁锰氧化物结合态、有机质结合态、和残渣态Pb的含量变化及其与土壤蚯蚓体内Pb含量的关系,结果表明:横滨市土壤表层全Pb含量在76.85~100.05mgkg-1之间,5~20cm土层全Pb含量为40.83~57mgkg-1之间,远高于当地的土壤Pb背景值(17mgkg-1),受到不同程度的污染;并且横滨国立大学校内绿地土壤比国道两侧绿地土壤表层的全Pb含量显著提高,其污染原因有待于进一步研究。蚯蚓体内的Pb含量变化范围在在研究区各采样点中没有显著差异,统计分析结果表明,蚯蚓体内的Pb含量与土壤环境中各形态Pb之间并无线性相关关系。 相似文献
24.
Molecular characterization of an H1N2 swine influenza virus isolated in Miyazaki, Japan, in 2006 总被引:1,自引:0,他引:1
Saito T Suzuki H Maeda K Inai K Takemae N Uchida Y Tsunemitsu H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(4):423-427
Swine influenza virus (SIV) was isolated from a farm in Miyazaki Prefecture in Japan in July 2006. An isolate was genetically subtyped as H1N2 and was designated A/swine/Miyazaki/1/2006 (H1N2). The nucleotide sequences of all eight viral RNA segments were determined, and then phylogenetic analysis was performed using the neighbor-joining method. All segments were shown to be closely related to those of Japanese SIV H1N2 isolates, which have been circulating since the 1980s. The results indicate the persistence of the SIV H1N2 subtype in the Japanese pig population for more than two decades and emphasize the importance of continuous surveillance for SIV. 相似文献
25.
We have characterized the cell surface properties of three mutant series of Pseudomonas aeruginosa that show various defects in their lipopolysaccharide (LPS) core region. The deepest rough mutants of each series used in this study lacked completely rhamnose and glucose, and contained only galactosamine and alanine as LPS outer core constituents. However, rough mutants other than the deepest rough mutants showed high cell surface hydrophobicity compared to the corresponding parental strains, the deepest rough mutants showed less hydrophobicity than other rough mutants. The reactivity of an anti-lipid A monoclonal antibody with the deepest rough mutants was markedly higher than that with other counterparts. The deepest rough mutants tended to be more susceptible to antibiotics, such as gentamicin and polymyxin B, than the corresponding parental strains and other rough mutants. The above evidence indicates that neutral sugar, namely rhamnose and glucose, residues of the LPS outer core region play a critical role in the cell surface properties of P. aeruginosa. 相似文献
26.
The external layer of a teleost fish scale is composed of type I collagen, an amorphous matrix substance and hydroxyapatite
crystals. Calcification of this layer can be inhibited in the scale-regenerating process under calcium- and phosphate-deficient
(CaDPD) conditions, and can be facilitated by incubation in physiological saline. The aim of this study was to evaluate this
model of calcification using histological and quantitative analysis in order to promote further understanding of the mechanism
of calcification in fish scales. We found that the external layer of the scales produced under CaDPD conditions contained
more densely aligned collagen fibrils with a small amount of the amorphous matrix substance. The CaDPD scale contained only
one-third of the amount of calcium and phosphate present in the control fish. After 4 hours of incubation, a two- to threefold
increase in calcium content and a 1.5-fold increase in phosphate content were observed. Calcification proceeded in the external
layer, and mineral deposits grew only in the electron-dense matrix substance. We conclude that this model would be suitable
for studying the early process of fish scale calcification that occurs in the noncollagenous substance. The electron-dense
substance may contain key molecules that promote calcification. 相似文献
27.
Takishita Kiyotaka Kawai Rihoko Tsutsumi Ayaka Tanifuji Goro Otsubo Mayuko 《Fisheries Science》2020,86(4):633-643
Fisheries Science - Tidal flats are ecologically important as they support a large community of animals (e.g., crabs, mollusks, and polychaetes) and restore water quality. However, information... 相似文献
28.
Konomi Sakamoto Wataru Honto Masaharu Iguchi Nobuhiro Ogawa Kazuhiro Ura Yasuaki Takagi 《Fisheries Science》2009,75(1):91-98
This study examines the following in the Japanese mitten crab: (1) the structure of the exoskeleton with special reference
to its calcification; (2) the progression of post-molt cuticle formation and calcification. In the crab, the structure and
calcification state of the exoskeleton at the molt and during the inter-molt stage were similar to those of other crustaceans.
During the inter-molt, the exoskeleton consisted of four cuticle layers; the outermost epicuticle, the exocuticle, the endocuticle
and the innermost membrane layer. Intense calcification was observed in the exo- and endocuticle. At the molt, the synthesis
of the epi- and exocuticle was already complete, and the addition of the endocuticle began after the molt. Calcification of
the exocuticle initiated soon after the molt, but there was a delay between endocuticle matrix synthesis and calcification.
Histology showed that the process of calcification was similar to that in other crustaceans. However, calcium concentrations
within the exoskeleton continued to increase and never reached the levels of the inter-molt stage at the end of the experiment.
This suggests that the Japanese mitten crab is relatively slow to calcify compared to other crustaceans. 相似文献
29.
Yasuro Iwashita Nobuhiro Suzuki Hiroyuki Matsunari Tsuyoshi Sugita Takeshi Yamamoto 《Fisheries Science》2009,75(5):1307-1315
To investigate the cause of the changes in intestinal morphology and biliary bile status of rainbow trout Oncorhynchus mykiss fed defatted soybean meal (SBM)-based diets, casein-based semipurified diets supplemented with soya saponin, soya lectin,
and cholyltaurine were fed to rainbow trout for 6 weeks. An unsupplemented control diet and a SBM-based diet were also tested
as references. Poor development of microvilli and pinocytotic vacuoles, and accumulation of large vacuoles in the epithelial
cells were observed in the distal intestine of fish fed diets containing saponin but not cholyltaurine. Hyperplastic connective
tissue in the mucosal folds of the distal intestine was observed in fish fed a diet containing both saponin and lectin but
not cholyltaurine. However, intestinal histological features in fish fed diet supplemented with cholyltaurine and lectin and/or
saponin were similar to those in the control diet group. Liver morphology and biliary bile status were not affected by saponin
and lectin. These results suggest that the abnormal features of the distal intestine of rainbow trout fed SBM-based diets
are caused by the combination of soya saponin and soya lectin, and that supplemental cholyltaurine plays certain roles in
normalizing the intestinal abnormalities caused by the saponin and lectin. 相似文献
30.
Kei Oyoshi Nobuhiro Tomiyama Toshio Okumura Shinichi Sobue Jun Sato 《Paddy and Water Environment》2016,14(4):463-472
In Asia, rice is a staple cereal crop and the continent accounts for about 90 % of the global rice production and consumption. Statistics on the areas planted with rice or production of paddy rice are fundamental to agriculture-related decisions or policy-making. Asia-Rice Crop Estimation & Monitoring (Asia-RiCE) aims to develop rice-related information, such as paddy field maps, rice growing conditions, yield, and production, using remote sensing tools and disseminate the same at the local and global scales. In this paper, we propose a methodology for the identification of rice-planted areas by using multi-temporal SAR images; a software named INternational Asian Harvest mOnitoring system for Rice (INAHOR) was developed to manipulate the proposed algorithm. The INAHOR uses the imagery observed both at the time of planting of rice and grown-up stages. In this study, two thresholds needed for the INAHOR were optimized based on the detailed land cover data collected through a field survey. Rice-planted areas across the study area in Japan were identified by the INAHOR using the RADARSAT-2 Wide Fine beam mode data. The classification results of RADARSAT-2 VV and VH polarizations were compared. The data with VH polarization showed a higher total accuracy of 83 % with ?20.5 dB and 3.0 dB for the minimum and range thresholds, respectively. The INAHOR is currently being used with the RADARSAT-2, ALOS, and ALOS-2 SAR data in the Southeast Asian countries to assess the robustness of the thresholds and classification accuracies under the framework of Asia-RiCE. 相似文献