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排序方式: 共有989条查询结果,搜索用时 156 毫秒
1.
2.
J M Mato 《Biochemical and biophysical research communications》1979,88(2):569-574
Human leucocyte cell cultures were stimulated to initiate DNA synthesis by phytohemagglutinin and mercuric chloride. Both mitogens enhanced the accumulation of β2-microglobulin in the medium, which was synthesized by lymphocytes. Mercuric chloride promoted the accumulation of this protein optimaly with a concentration (1 × 10?5M) to produce the maximum stimulation of DNA synthesis. Combined use of phytohemagglutinin (50 μg/ml) and mercuric chloride (1 × 10?5M) produced additive effect on both DNA synthesis and β2-microglobulin accumulation. These findings suggest that mercuric ion causes the proliferative response of lymphocytes by a mechanism different from that for the stimulation by phytohemagglutinin. 相似文献
3.
Undifferentiated embryonal carcinoma cells (EC cells) in the embryoid bodies isolated from mouse teratocarcinoma contained nucleolus-like bodies (NLBs) of smaller sizes in their cytoplasm (their sectional area averaged about 0.036 μm2). At the onset of EC cell differentiation, the average sectional area of NLBs significantly increased (about 0.107 μm2). When EC cells had differentiated into mesenchymal cells and endothelial cells of primitive blood vessels, NLBs decreased dramatically both in size and number. The possible role of NLBs in the differentiation process of EC cells is discussed. 相似文献
4.
Pornparn Kongpracha Pattama Wiriyasermkul Noriyoshi Isozumi Satomi Moriyama Yoshikatsu Kanai Shushi Nagamori 《Molecular & cellular proteomics : MCP》2022,21(5):100206
Membrane proteins play essential roles in various cellular processes, such as nutrient transport, bioenergetic processes, cell adhesion, and signal transduction. Proteomics is one of the key approaches to exploring membrane proteins comprehensively. Bottom–up proteomics using LC–MS/MS has been widely used in membrane proteomics. However, the low abundance and hydrophobic features of membrane proteins, especially integral membrane proteins, make it difficult to handle the proteins and are the bottleneck for identification by LC–MS/MS. Herein, to improve the identification and quantification of membrane proteins, we have stepwisely evaluated methods of membrane enrichment for the sample preparation. The enrichment methods of membranes consisted of precipitation by ultracentrifugation and treatment by urea or alkaline solutions. The best enrichment method in the study, washing with urea after isolation of the membranes, resulted in the identification of almost twice as many membrane proteins compared with samples without the enrichment. Notably, the method significantly enhances the identified numbers of multispanning transmembrane proteins, such as solute carrier transporters, ABC transporters, and G-protein–coupled receptors, by almost sixfold. Using this method, we revealed the profiles of amino acid transport systems with the validation by functional assays and found more protein–protein interactions, including membrane protein complexes and clusters. Our protocol uses standard procedures in biochemistry, but the method was efficient for the in-depth analysis of membrane proteome in a wide range of samples. 相似文献
5.
《European journal of protistology》2014,50(5):496-508
Three species of Diophrys, D. peculiaris nov. spec., D. cf. scutum and D. oligothrix, isolated from the New Nagasaki Fishing Port, Nagasaki, Japan, were investigated using live observation and protargol impregnation. Diophrys peculiaris nov. spec. can be recognized by having two characteristic clusters of rod-like structures and two groups of dikinetids located on anterior dorsal portion of cell. Morphogenetic data show that this part of the life cycle basically proceeds as in congeners, except for the formation of dikinetids under the rod-like structures. In the opisthe, the origin of dikinetids under the rod-like structures is still unknown, but the old dikinetids under the rod-like structures may be retained by the proter. The Japanese population of Diophrys cf. scutum resembles other populations of D. scutum well except for moniliform macronuclear segments. Our populations of D. oligothrix correspond well with other populations in terms of general morphology and ciliary pattern, in particular the continuous dorsal kineties with loosely arranged cilia. 相似文献
6.
Functional redundancy of multiple forest taxa along an elevational gradient: predicting the consequences of non‐random species loss 下载免费PDF全文
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
7.
Brachypalpus (Brachypalpus) longifacies sp. nov. is described and illustrated from Eastern Asia (Russian Far East and Japan). It differs from other species of the nominative subgenus by several unusual characters, i.e. face in profile weakly convex dorsally and concave ventrally, antennae very elongated, and abdomen with reddish transversal maculae on 2nd tergum (male) or 2nd and 3rd terga (female). A key is given for known species of the subgenus Brachypalpus.LSID: urn:lsid:zoobank.org:pub:634CB6E2-B2C1-40EC-8811-BF3DD4BDE69A 相似文献
8.
A. A. Kepel' 《Russian Journal of Marine Biology》2000,26(6):450-452
The alga Analipus japonicus (Harv.) Wynne displays a distinct seasonal pattern in its development in Peter the Great Bay (Sea of Japan). In winter and spring, it occurs only in the form of basal crusts, and vertical axes develop in the summer–autumn period. It reproduces mostly asexually from July to November. Algae with unilocular sporangia occur very seldom, only in June and July. 相似文献
9.
A method for quantitative appraisal of disturbances of macrobenthic communities of soft substrata caused by anthropogenic pollution is proposed. This method is based on the establishment of the dependence of various parameters characterizing the abundance and structure of communities (biomass, population density, number of species, Shannon-Weaver and Pielou indices, etc.) on the level of total contamination of bottom sediments. Using the percentage of deviation of abundance parameters and ecological indices from the norm (the initial horizontal segment of model curves), as well as ERL q and ERM q values, which limit the area of progressive degradation of bottom communities (an almost linear drop in abundance and structure characters), is suggested as a numerical characteristic of such deformations. Mapping of aqueous areas on the basis of these characteristics enabled us to obtain a synoptic view of the extent and spatial scale of anthropogenic impacts. An example of the application of this method for assessment of the state of benthic communities in the Peter the Great Bay (Sea of Japan) is shown for the end of the 1980s. The method is verified on the basis of comparison with the results obtained by standard methods of appraisal of the ecological status of macrozoobenthic communities. 相似文献
10.
To examine geographic differentiation in Asarum heterotropoides var. heterotropoides in Hokkaido Is. in the northern Japan, in which two putative cryptic species have been suspected to exist, extensive and
detailed morphological research on 794 individuals from 44 populations throughout Hokkaido Is. was performed. Among the characters
examined, the angle between and tip shape of the calyx lobes and the supratecta of the pollen grains were significantly correlated
and were found in similar geographic clines. Among them, the pollen showed two discrete states in almost distinct distribution.
Multidimensional scaling analysis showed that individuals within each of the two pollen types had different trends in flower
characters. Consequently, we assumed a cline from south to north on Hokkaido Is. For the causes of the cline, the two hypotheses
were proposed, primary geographic differentiation or extensive introgressive hybridization between two distinct geographical
species existing in the past. 相似文献