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801.
Allergen induced histamine release and immunoreactive-leukotriene C4 generation from leukocytes in mite sensitive asthmatic patients 总被引:2,自引:0,他引:2
Leukocytes from mite sensitive asthmatic patient were challenged with the allergen and the supernatant was assayed for histamine and immunoreactive-leukotriene C4 (i-LTC4). The release of histamine was quantitated by an automated fluorometric technique and i-LTC4 was determined using a commercial radioimmunoassay kit. The results of analysis of the supernatant by high speed liquid chromatography, together with observations of modulation of the formation by agents, indicated that i-LTC4 consisted of LTC4 with a little amount of LTD4. i-LTC4 was generated as a result of basophil activation but not derived from the other cells such as monocytes and eosinophils. Allergen induced a concentration-dependent release of histamine and i-LTC4 and the maximal release of histamine and i-LTC4 occurred at the same dose of the allergen. At optimal concentration of the allergen, basophils produced 20.4 +/- 17.9 ng of i-LTC4/10(6)-cells (mean +/- S.D., n = 39) and histamine release was 55.6 +/- 20.1% of total histamine. There was a significant correlation in the capacity of leukocytes to release histamine and i-LTC4 (r = 0.47, p less than 0.01). We found a correlation between maximal histamine release or cell sensitivity, allergen concentration for 50% histamine release, and a ratio of specific IgE to mite to total IgE in the serum, but the amount of i-LTC4 failed to correlate significantly with the ratio. The releasability and the cell sensitivity of asthmatic patients' cells to the allergen for histamine release paralleled the severity to symptoms, but this correlation was not significant in i-LTC4 generation. 相似文献
802.
Ichiro Tayasu Riyo Hirasawa Nanako O. Ogawa Naohiko Ohkouchi Keita Yamada 《Limnology》2011,12(3):261-266
We determined both carbon and nitrogen isotope ratios of ten organic reference materials (CERKU-01 to CERKU-10) in the Center
for Ecological Research (CER), Kyoto University, and three organic reference materials (BG-A, BG-P, and BG-T) in the Institute
of Biogeosciences (BioGeos), Japan Agency for Marine-Earth Science and Technology (JAMSTEC), using an internationally recommended
calibration method of two-point anchoring. The reference materials cover δ13CVPDB range of −34.92 to −9.45‰ and δ15NAir range of −5.22 to 22.71‰ and can be used to measure isotope ratios of naturally occurring substances. 相似文献
803.
Martin Fikáček Shûhei Yamamoto Keita Matsumoto Rolf G. Beutel David R. Maddison 《Systematic Entomology》2023,48(2):233-249
Sphaeriusidae (Coleoptera: Myxophaga) is a group of shiny, blackish and hemispherical riparian beetles, known for their miniaturized bodies. They are worldwide in distribution, but very limited information is available about taxonomic and morphological diversity, and natural and evolutionary history. The aim of this study is to help fill in these gaps. We examined the external morphology of modern representatives using scanning electron microscopy (SEM), and reconstructed the phylogeny of the family using five DNA markers (cytochrome oxidase I, 18S rRNA, 28S rRNA, CAD and wingless). Our results suggest a larger morphological diversity than previously expected, corresponding to the deep genetic divergences of principal lineages. We also examined two inclusions in 99-million-year-old Burmese amber. The integration of all evidence allows us to recognize three genera: the extinct genus †Burmasporum Kirejtshuk, the newly defined genus Bezesporum gen.nov. preserved in Burmese amber (B. burmiticum sp.nov. ) and present in the modern fauna of Southeast Asia, and the genus Sphaerius Waltl with a world-wide distribution. Sphaerius species are morphologically highly uniform, with the exception of species from Australia and South Africa, which share some characteristics with Bezesporum gen.nov. despite being resolved as deeply nested lineages of Sphaerius by DNA data. The presence of Bezesporum gen.nov. in Burmese amber and in recent fauna indicates that Sphaeriusidae largely maintained their specific morphology and specialized riparian lifestyle for at least 100 million years. Therefore, they can be considered an exceptionally conserved group, with a minimum of evolutionary changes over a long period. Our study also demonstrates that the species numbers and fine-scale morphological diversity of Sphaeriusidae are larger than expected in both the past and present-day faunas. Both were apparently underestimated due to the minute body size and cryptic habits of these beetles. 相似文献
804.
Takaya Sugawara Tsubasa Furuhashi Kenji Shibata Masayuki Abe Keita Kikuchi Masato Arai 《Bioscience, biotechnology, and biochemistry》2019,83(8):1484-1489
ABSTRACTRice kefiran is superior in functionality, has high concentration of mucilaginous polysaccharide, and low lipid content, compared to conventional kefiran. However, reports on its physiological functionality, especially studies on life expectancy and aging, in model organisms are rare. In this study, nematodes were used as model organisms that were fed rice kefiran, along with Escherichia coli OP50, as a result of which, the lifespan of nematodes was extended and age-related retardation of mobility was suppressed. It also increased the heat stress resistance in nematodes. Experiments using daf-16 deletion mutant revealed that rice kefiran functions via DAF-16. Thus, this study revealed the longevity, anti-aging and heat stress tolerance effects of rice kefiran in nematodes. 相似文献
805.
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808.
Fukasawa Keita Mishima Yoshio Yoshioka Akira Kumada Nao Totsu Kumiko Osawa Takeshi 《Ecological Research》2016,31(4):493-493
In 2011, the Fukushima Daiichi Power Plant accident resulted in the evacuation of about 81,000 people from the evacuation zone, which suffered from high levels of radioactive contamination. Large-scale and long-term land abandonment can cause changes in species assemblages. Despite the extensive global attention this incident received, open and spatially-explicit datasets of mammal fauna from Fukushima remain quite limited. We established a continuous monitoring protocol using camera traps for mammals both inside and outside the evacuation zone; this paper presents our first dataset. These data represent the monitoring results from 45 camera traps from May 2014 to October 2014, including the location and actuation time of each camera, and the list of video records. After the publication of this initial data paper, we intend to continue monitoring until 2023 and the dataset will be hereafter updated with new observations. 相似文献
809.
B. Enanga C. Labat H. Boudra G. Chauvière M. Keita B. Bouteille M. Dumas G. Houin 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1997,696(2):213
A simple and sensitive high-performance liquid chromatographic method has been developed to measure megazol in human plasma. The method was optimized and validated according to the Washington Concensus Conference on the Validation of Analytical Methods (V.P. Shah et al., Eur. J. Drug Metab. Pharmacokinet., 15 (1991) 249). The criteria of complete validation were specificity, linearity, precision, analytical recovery, dilution and stability. It involved extraction of the plasma with dichloromethane, followed by reversed-phase high-performance liquid chromatography using a KromasilR C8 column and UV detection at 360 nm. The retention times of the internal standard (tinidazol) and megazol were 6.10 and 9.60 min, respevtively. The standard curve was linear from 2 ng ml−1 (limit of quantification) to 2000 ng ml−1. The coefficients of variation for all the criteria of validation were less than 6%; 85 to 92% extraction efficiencies were obtained. Megazol was stable during the storage period (one month at −20°C) in plasma and for two months at 25°C in standard solution. The method was tested by measuring the plasma concentration following oral administration to rat and was shown to be suitable for pharmacokinetic studies. 相似文献
810.