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51.
Y Nagai K Akiyama S Kotani Y Watanabe T Shimono T Shiba S Kusumoto 《Cellular immunology》1978,35(1):168-172
The peptide N-acetylmuramyl-l-alanyl-d-isoglutamine (MDP), which has adjuvant activities, and 17 of its derivatives and analogs were synthesized and assayed to elucidate the structure necessary for adjuvant activity in induction of experimental allergic encephalomyelitis (EAE) in guinea pigs. The results revealed the importance of the d configuration and the α-carboxamide group of the isoglutaminyl residue of MDP for adjuvant activity. Replacement of the l-alanyl residue of MDP by d-alanine, but not by l-serine or glycine, resulted in a marked decrease in the activity. The β-methyl glycoside of MDP was found to be more active than the α-methyl derivative. 6-O-Stearoyl-N-acetylmuramyl-l-alanyl-d-isoglutamme showed activity. 相似文献
52.
Using an EA rosetting system, it was observed that Fc receptors (FcR) were present on the surface of T cells as well as B cells, and that functional differences existed between FcR-positive (FcR+) and FcR-negative (FcR?) cells in both T and B cells in in vivo humoral immune responses. Approximately 15% of splenic T cells obtained by nylon wool passage are FcR+. The number of surface immunoglobulinbearing cells as detected by immunofluorescent staining accounted for less than 10% of these FcR+ cells. FcR+ and FcR? T+B-cell populations obtained from spleens contain 60 and 20% of surface immunoglobulin-positive cells, respectively. In the adoptive primary response in which horse RBC and dinitrophenyl-conjugated dextran (DNP-DE) were used as T-dependent and T-independent antigens, respectively, the majority of precursor B cells were FcR?. In the secondary response using hapten-primed B cells and carrier-primed T cells, the majority of memory B cells for a haptenic determinant were also FcR?. Furthermore, the majority of functional cells exerting helper activity in the same hapten-carrier system are FcR? cells, and FcR+ T cells collaborate much less effectively with either memory B cells or helper FcR? T cells. 相似文献
53.
New topics on ecology and systematics of recent and fossil Lingulids lead to an obvious revision of our knowledges on this zoological group. At first, the recent species need systematics and taxonomy on the bases of new described specific criteria (as, morphology of deltidial areas, muscle disposition); the results are briefly indicated. But, in fossil species, disorder and disparity of used characteristics are emphasized.The general conceiving on ecology of Lingulids are reviewed and discussed, especially on bathymetry and salinity; sediment and oxygenation conditions; taphocoenosis and lingulid «communities. On recent species, all these points are also studied, especially some ecological requirements (salinity, bathymetry, grain size), and mechanism of burrowing ability, burrow living positions in the sediments, as shell preservations after death and fossilization, to facilitate the paleobiotope interpretations. Recent animals are euryhalin, surviving at salinities from about 13 to 42‰; they could be considered as well adapted to waters with strong salinity fluctuations. They show preference to fine sand bottoms (lowest particle size about 40–60 μm). Their bathymetric distribution occurs between 0 and about 500 m (Lingula especially between 5–50 m; Glottidia 15–70 m). The isotherms 8–10°C seem to restrict their geographical and bathymetric distribution.Therefore, some post-palaeozoic lingulid bedsare studied or redescribed on the bases of the above discussed characteristics, and new interpretations on the environmental situation are given (Trias of Vosges Mountains; Oligocene from Japan; Eocene of London Basin). More caution must be used in study of fossil Lingulids that are not especially animals living in infralittoral bottoms with low salinity and deficient oxygenation, as generally accepted. 相似文献
54.
55.
Functional redundancy of multiple forest taxa along an elevational gradient: predicting the consequences of non‐random species loss
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Akira S. Mori Takayuki Shiono Takashi F. Haraguchi Aino T. Ota Dai Koide Takayuki Ohgue Ryo Kitagawa Ryo Maeshiro Toe Toe Aung Taizo Nakamori Yusuke Hagiwara Shunsuke Matsuoka Anzu Ikeda Takuo Hishi Satoru Hobara Eri Mizumachi Andreas Frisch Göran Thor Saori Fujii Takashi Osono Lena Gustafsson 《Journal of Biogeography》2015,42(8):1383-1396
56.
Various Pt(II)-glycine coordination compounds were characterized by 1H and 13C NMR spectroscopy, some of them also by electrophoretic and chromatographic behavior. The results were applied to the analysis of the reaction mixtures of cis-[Pt(NH3)2Cl2] and glycine obtained under various conditions. Cis-[Pt(NH3)2Cl2] reacts with glycine to give cis-diammine-(glycine-N,O)-Pt(II) and cis-diammine-bis(glycine-N-)Pt(II). Their ratio depends primarily on the pH of the reaction medium. Conformation of these compounds is discussed based on the observed Pt-C and Pt-H NMR coupling constants. 相似文献
57.
《Saudi Journal of Biological Sciences》2020,27(8):2065-2075
The marine microbiome is a complex and least-understood habitat, which play a significant role in global biogeochemical cycles. The present study reported the culture-independent assessment of microbial diversity from the Arabian Sea (AS) sediments (from Gujarat to Malabar; at 30 m depth) by using metagenome sequence analysis. Our results elucidated that bacterial communities in the Malabar coastal region are highly diverse than the Gujarat coast. Moreover, Statistical analysis (Spearman rank correlation) showed a significant correlation co-efficient value (r = P < 0.001) between microbial communities and physicochemical parameters (salinity and dissolved oxygen) in the water column. A total of 39 bacterial phyla were recorded from the eastern side of AS, of which six phyla Proteobacteria, Bacteroidetes, Actinobacteria, Cyanobacteria, Firmicutes, and Planctomycetes were found to be the most dominant group. The most dominant genus from Valapad region (Malabar Coast) was found to be Halomonas sp., while other regions were dominated with Psychrobacter pulmonis. The subsequent Principal Coordinate Analysis (PCoA) showed 99.53% variance, which suggests that, highly distinct microbial communities at Valapad (Malabar Coast) sampling location than other sites. Moreover, the microbial metabolic activity analysis revealed the important functions of microbial communities in the AS are hydrocarbon degradation, polymer degradation, nutrient oxidation and sulphate reduction (biodegradation process). Further extended studies are needed to be carried out for better understanding the functional diversity of microbial communities from the marine sediments. 相似文献
58.
《L'Anthropologie》2021,125(5):102955
The northeastern area of Honshu is composed of six departments: Aomori, Iwate, Akita, Miyagi, Yamagata and Fukushima. The study of Paleolithic began in 1927 and has given place to the discovery of the site of Hanaizumi. Subsequently, one pushed the research below on land and the discovery of the first paleolithic site in Iwajyuku happened in 1946. Then, H. Nakagawa took back a success of survey of the geomorphological processes and the ordering of the fluviatile terraces with some layers from the volcano-sedimentary deposit of the Pleistocene in the basin of Kitakami and the one of Mabechi. Therefore, we understood that the archaeological levels of the region contain several sedimentary deposits volcano of quaternary origin from the Mounts Öu. In the basin of Kitakami, one noted the deposit of fall pyroclastic of Aiçra (AT) above the layer of the local volcanic ash from Kurosawajiri. Especially, it is one key of an important layer, the last horizon located under AT and above the tephra of Daïfudô from the local volcano, the pyroclastic stream of Towada and the involution of the layer of the volcanic ash from Kurosawajiri. More than 610 paleolithic sites has been counted in the Northeast. 相似文献
59.
Norman K.B. Robson 《分类学与生物多样性》2013,11(1):19-98
Abstract Part 4(3) of this monographic series of papers on the genus Hypericum is prefaced by an introduction to the genus and a summary of the aims and methods of the project. This is followed by treatments of the remaining parts of sect. 9. Hypericum sensu stricto and the last segregate section from the original sect. Hypericum, sect. 9b. Graveolentia. Both hitherto untreated parts of the reduced sect. Hypericum are mainly Japanese, but some species extend in distribution as far as Kamchatka, eastern Siberia, central China, and Sabah (Mt. Kinabalu). Sect. Graveolentia is North and Central American. Sect. Hypericum subsect. Hypericum series Senanensia contains seven species from northern Japan and adjacent areas, including H. pibairense (Miyabe & Y. Kimura) N. Robson, stat. nov., H. nakaii subsp. miyabei (Y. Kimura) N. Robson, comb. et stat. nov., H. nakaii subsp. tatewakii (S. Watanabe) N. Robson, comb. et stat. nov. and H. senanense subsp. mutiloides (R. Keller) N. Robson, comb. et stat. nov. Sect. Hypericum subsect. Erecta contains 23 species and one hybrid from Japan, Korea, central China, Taiwan, Luzon, Sabah and Sumatera, including H. kawaranum N. Robson, stat. et nom. nov., H. watanabei N. Robson, stat. et nom. nov., H. kimurae N. Robson, stat. et nom. nov., H. pseudoerectum stat. et nom. nov., H. kitamense (Y. Kimura) N. Robson, stat. nov., H. kurodakeanum N. Robson, stat. et nom. nov., H. furusei N. Robson, sp. nov., H. nuporoense N. Robson, sp. nov. and H. ovalifolium subsp. hisauchii (Y. Kimura) N. Robson, stat. nov. Sect. Graveolentia contains nine species and one hybrid from southeastern Canada, the eastern half of the United States, Mexico and western Guatemala, including H. oaxacanum subsp. veracrucense N. Robson, subsp. nov. and H. macvaughii N. Robson, sp. nov. 相似文献
60.
The genus Lasinus Sharp, 1874 of the Pselaphodes complex of genera (Pselaphitae: Tyrini: Tyrina) is revised. The three so far known species, Lasinus mandarinus Raffray, 1890, Lasinus monticola Sawada, 1961 and Lasinus spinosus Sharp, 1874 are redescribed. Eight new species, Lasinus sinicus
sp. n. from China, Lasinus mikado
sp. n., Lasinus yamamotoi
sp. n., Lasinus inexpectatus
sp. n., Lasinus yakushimanus
sp. n., Lasinus amamianus
sp. n., Lasinus saoriae
sp. n., and Lasinus okinawanus
sp. n. from Japan, are described. And all species are illustrated. Lectotypes are designated for Lasinus mandarinus and Lasinus spinosus. An identification key to species of the genus Lasinus is provided. 相似文献