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991.
Molecular signatures distinguish human central memory from effector memory CD8 T cell subsets 总被引:6,自引:0,他引:6
Willinger T Freeman T Hasegawa H McMichael AJ Callan MF 《Journal of immunology (Baltimore, Md. : 1950)》2005,175(9):5895-5903
Memory T cells are heterogeneous in terms of their phenotype and functional properties. We investigated the molecular profiles of human CD8 naive central memory (T(CM)), effector memory (T(EM)), and effector memory RA (T(EMRA)) T cells using gene expression microarrays and phospho-protein-specific intracellular flow cytometry. We demonstrate that T(CM) have a gene expression and cytokine signaling signature that lies between that of naive and T(EM) or T(EMRA) cells, whereas T(EM) and T(EMRA) are closely related. Our data define the molecular basis for the different functional properties of central and effector memory subsets. We show that T(EM) and T(EMRA) cells strongly express genes with known importance in CD8 T cell effector function. In contrast, T(CM) are characterized by high basal and cytokine-induced STAT5 phosphorylation, reflecting their capacity for self-renewal. Altogether, our results distinguish T(CM) and T(EM)/T(EMRA) at the molecular level and are consistent with the concept that T(CM) represent memory stem cells. 相似文献
992.
Diterpenoid phytoalexin factor,a bHLH transcription factor,plays a central role in the biosynthesis of diterpenoid phytoalexins in rice 下载免费PDF全文
993.
Toru Fukuda Shoichiro Kokabu Satoshi Ohte Hiroki Sasanuma Kazuhiro Kanomata Katsumi Yoneyama Hitoshi Kato Masumi Akita Hiromi Oda Takenobu Katagiri 《Differentiation; research in biological diversity》2010
Both BMPs and Wnts play important roles in the regulation of bone formation. We examined the molecular mechanism regulating cross-talk between BMPs and Wnts in the osteoblastic differentiation of C2C12 cells. Canonical Wnts (Wnt1 and Wnt3a) but not non-canonical Wnts (Wnt5a and Wnt11) synergistically stimulated ALP activity in the presence of BMP-4. Wnt3a and BMP-4 synergistically stimulated the expression of type I collagen and osteonectin. However, Wnt3a did not stimulate ALP activity that was induced by a constitutively active BMP receptor or Smad1. Noggin and Dkk-1 suppressed the synergistic effect of BMP-4 and Wnt3a, but Smad7 did not. Overexpression of β-catenin did not affect BMP-4-induced ALP activity. By contrast, inhibition or stimulation of GSK3β activity resulted in either stimulation or suppression of ALP activity, respectively, in the presence of BMP-4. Taken together, these findings suggest that BMPs and canonical Wnts may regulate osteoblastic differentiation, especially at the early stages, through a GSK3β-dependent but β-catenin-independent mechanism. 相似文献
994.
Stimulatory effects of islet amyloid polypeptide (amylin) on exocrine pancreas and gastrin release in conscious rats. 总被引:2,自引:0,他引:2
A Funakoshi K Miyasaka K Kitani J Nakamura S Funakoshi H Fukuda N Fujii 《Regulatory peptides》1992,38(2):135-143
A rat islet amyloid polypeptide (amylin), 37-residue peptide amide was synthesized by the Fmoc-based solid phase method and the biological activity of synthetic rat amylin on exocrine pancreas was evaluated for the first time in conscious rat. Amylin (1, 10 nmol/kg/h) stimulated pancreatic exocrine secretion and plasma gastrin concentration. CR-1409, a CCK receptor antagonist, did not change amylin-stimulated pancreatic secretion. However, omeprazole (proton pump inhibitor) and atropine inhibited amylin-stimulated pancreatic secretion. This study suggests that amylin may play a role in biological action in the exocrine pancreas possibly mediated by gastric acid hypersecretion. 相似文献
995.
XS Qi C Chen HP Comes S Sakaguchi YH Liu N Tanaka H Sakio YX Qiu 《The New phytologist》2012,196(2):617-630
? East Asia's temperate deciduous forests served as sanctuary for Tertiary relict trees, but their ages and response to past climate change remain largely unknown. To address this issue, we elucidated the evolutionary and population demographic history of Cercdiphyllum, comprising species in China/Japan (Cercdiphyllum?japonicum) and central Japan (Cercdiphyllum magnificum). ? Fifty-three populations were genotyped using chloroplast and ribosomal DNA sequences and microsatellite loci to assess molecular structure and diversity in relation to past (Last Glacial Maximum) and present distributions based on ecological niche modelling. ? Late Tertiary climate cooling was reflected in a relatively recent speciation event, dated at the Mio-/Pliocene boundary. During glacials, the warm-temperate C.?japonicum experienced massive habitat losses in some areas (north-central China/north Japan) but increases in others (southwest/-east China, East China Sea landbridge, south Japan). In China, the Sichuan Basin and/or the middle-Yangtze were source areas of postglacial northward recolonization; in Japan, this may have been facilitated through introgressive hybridization with the cool-temperate C.?magnificum. ? Our findings challenge the notion of relative evolutionary and demographic stability of Tertiary relict trees, and may serve as a guideline for assessing the impact of Neogene climate change on the evolution and distribution of East Asian temperate plants. 相似文献
996.
Photosynthesis Research - Zinc 3-hydroxymethyl-131-oxo-chlorins bearing a variety of primary alkyl groups at the 20-position were prepared as models of bacteriochlorophyll-c by chemical... 相似文献
997.
Akisue Kuramoto Hitoshi Kimura Norio Inou 《Molecular & cellular biomechanics : MCB》2019,16(4):235-243
Comfortable bedding is usually designed subjectively because of the difficulty in performing a quantitative evaluation. This paper proposes a quantitative evaluation method of comfortableness of beddings. The bedding shape determining how comfortable an individual may feel in using it depends on the body shape and normal posture of individuals. The internal physical load is expected to relate to the comfortableness of bedding. However, only a few quantitative discussions exist on the relation between the comfortableness of bedding and physical load. This study proposes a new evaluation method of physical load in a relaxed posture. The strain energy of muscles and joints was used as an indicator of physical load. To estimate physical load, a neutral body position was simulated from a natural standing posture and was used as a reference posture with the neutral condition of muscle lengths. By considering individual differences, multiple models of neutral body position were provided. We simulated individual differences of a comfortable pillow height using the proposed models. Physical load in a relaxed posture was varied according to the models. Calculated results show that physical load becomes small when a pillow is comfortable. For both subjective pillow comfortableness and smallness of physical load, there is a similar tendency that the low pillow with the small height difference between head and neck is preferable if the concave depth of back shape of head and neck is small. Moreover, the results show that muscles and joints equally affect the comfortableness of designed pillow. This implies that less total energy required for maintaining the posture contributes to pillow comfortableness. 相似文献
998.
999.
Complementary DNA Cloning and Characterization of Ferredoxin
Localized in Bundle-Sheath Cells of Maize Leaves 总被引:3,自引:2,他引:1
1000.
Habitat selection by tufted ducks (Aythya fuligula), a diving duck which swallows benthic prey organisms, was studied during winter at two neighboring lagoons (Lakes Nakaumi and Shinji, Honshu, Japan) which differ strongly in their benthic fauna and in their diving duck densities. The ducks fed overwhelmingly on the dominant bivalve found in each of the two lagoons, the mussel Musculista senhousia in L. Nakaumi and the clam Corbicula japonica in L. Shinji. In general, however, the ducks probably preferred the mussels to the clams because of: (i) their high (2.9 times) calorific content for their weight; (ii) their high digestibility; (iii) their greater accessibility; and (iv) their shorter handling time. An average tufted duck (850 g) was estimated to require 1.3 kg of mussels or 3.8 kg of clams to meet their daily energy requirements. As a result, the two wintering populations were estimated to consume 4970 t mussels and 4770 t clams during a single wintering season, amounting to some 20% of the standing clam crop. Throughout the winter the average gizzard weight (37 g), and gizzard–body mass ratio (4.2%) of the Lake Nakaumi population were half those of the Lake Shinji population (73 g, 8.1%, respectively), despite their significantly similar nutritive body condition (% body lipid > 12%). The need to maintain a specialized gizzard mass in order to be able to cope with the different prey species results in little opportunity for sampling movements of birds between lakes/prey types and as a result two subpopulations of ducks are indicated to be segregated. 相似文献