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排序方式: 共有1577条查询结果,搜索用时 31 毫秒
1.
Xylan Synthase Activity in Isolated Mesophyll Cells of Zinnia elegans during Differentiation to Tracheary Elements 总被引:1,自引:0,他引:1
Suzuki Kaoru; Ingold Edgar; Sugiyama Munetaka; Komamine Atsushi 《Plant & cell physiology》1991,32(2):303-306
A paniculate fraction obtained from mesophyll cells of Zinniaelegans that were differentiating into tracheary elements exhibitedxylan synthase activity, catalyzing the transfer of MC-xylosefrom UDP-D-[U-14C]-xylose into 1,4-linked xylan. The activityincreased transiently at the same time as thickening of secondarycell walls occurred, a process that is accompanied by the depositionof cellulose, xylan and lignin. (Received August 3, 1990; Accepted December 6, 1990) 相似文献
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Ken Takahashi Toru Taguchi Kazunori Itoh Kaoru Okada Kenji Kawakita 《Somatosensory & motor research》2013,30(4):299-305
Transcutaneous pressure with pressure probes of arbitrary diameters have been commonly used for measuring the threshold and magnitude of muscle pain, yet this procedure lacks scientific validation. To examine the valid probe dimensions, we conducted physiological experiments using 34 human subjects. Pin-prick pain, pressure pain threshold (PPT) to pressure probes of various diameters, heat pain threshold, and electrical pain threshold of deep tissues were measured before and after application of surface lidocaine anesthesia to the skin surface over the brachioradial muscle in a double-blinded manner. The anesthesia neither affected PPT with larger probes (diameters: 1.6 and 15?mm) nor increased electric pain threshold of deep structures, whereas it diminished pain count in pin-prick test and PPT with a 1.0?mm diameter probe, suggesting that mechanical pain thresholds measured with 1.6 and 15?mm probes reflect the pain threshold of deep tissues, possibly muscle. Pain thresholds to heat did not change after application of the anesthesia. These results suggest that larger pressure probes can give a better estimation of muscular pain threshold. 相似文献
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H. Takami Yoshihiro Takaki Kaoru Nakasone Tokuki Sakiyama G. Maeno Rumie Sasaki Chie Hirama Fumie Fuji Noriaki Masui 《Extremophiles : life under extreme conditions》1999,3(3):227-233
Seventeen Sse8387I linking clones isolated from the chromosome of Bacillus halodurans C-125 for the purpose of constructing a physical map were sequenced and analyzed by comparison with the BSORF database and
the nonredundant protein databank. The orientations of Sse8387I or AscI linking clones serving to join adjacent fragments were determined by southern blot analysis using specific DNA probes. One-third
of the open reading frames (ORFs) identified in the Sse8387I linking clones showed no significant similarity to any protein so far reported. The ORFs showing significant similarities
to those of Bacillus subtilis were mapped in the chromosome of strain C-125, and the locations of the putative genes on the map were not well conserved
between B. halodurans C-125 and B. subtilis.
Received: March 26, 1999 / Accepted: April 27, 1999 相似文献
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C Tayama S Ichimaru M Ito M Nakayana M Maeyama I Miyakawa 《Endocrinologia japonica》1983,30(2):155-162
The levels of unconjugated estradiol (E2), estriol (E3) and total (conjugated plus unconjugated) E3 in maternal vein serum during labor, cord vein serum, and cord artery serum were measured in normal singleton and twin pregnancies with appropriate for dates babies (AFD) and with light for dates babies (LFD). The mean level of total E3 in the maternal vein serum in singleton pregnancy was significantly lower in the LFD group than in the AFD group, but no differences were seen in the mean levels of unconjugated E2 or E3 between the groups. The concentration of unconjugated E2 in the maternal vein serum was significantly higher in the twin group with a large placenta than in the singleton group with a smaller placenta, while the concentration of total E3 in the case of twin pregnancy with LFD was lower than that in singleton pregnancy with AFD but not significantly. No difference in the concentration of total E3 was observed between the cord vein serum and cord artery serum. The present data suggest that the total E3 level in maternal vein serum may be used in evaluating fetal states such as intrauterine growth retardation. 相似文献
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Tsuguo Sasaki Yuko Sasaki Toshiharu Matsumura Noriko Oyama Kaoru Koshimizu 《Microbiology and immunology》1989,33(5):423-427
A strain of Mycoplasma hominis lacking a major membrane protein of 120 kDa was isolated from a Vero cell culture. This strain showed very slow growth rate and formed nipple-less colonies on agar medium. 相似文献
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Oxyopinins (Oxki1 and Oxki2) are antimicrobial peptides isolated from the crude venom of the wolf spider Oxyopes kitabensis. The effect of oxyopinins on lipid bilayers was investigated using high-sensitivity titration calorimetry and 31P solid-state NMR spectroscopy. High-sensitivity titration calorimetry experiments showed that the binding of oxyopinins was exothermic, and the binding enthalpies (ΔH) to 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphatidylcholine (POPC) small unilamellar vesicles (SUVs) were − 18.1 kcal/mol and − 15.0 kcal/mol for Oxki1 and Oxki2, respectively, and peptide partition coefficient (Kp) was found to be 3.9 × 103 M− 1. 31P NMR spectra of 1,2-dielaidoyl-sn-glycero-3-phosphoethanolamine (DEPE) membranes in the presence of oxyopinins indicated that they induced a positive curvature in lipid bilayers. The induced positive curvature was stronger in the presence of Oxki2 than in the presence of Oxki1. 31P NMR spectra of phosphaditylcholine (PC) membranes in the presence of Oxki2 showed that Oxki2 produced micellization of membranes at low peptide concentrations, but unsaturated PC membranes or acidic phospholipids prevented micellization from occurring. Furthermore, 31P NMR spectra using membrane lipids from E. coli suggested that Oxki1 was more disruptive to bacterial membranes than Oxki2. These results strongly correlate to the known biological activity of the oxyopinins. 相似文献