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排序方式: 共有3549条查询结果,搜索用时 15 毫秒
1.
Stability increments of 3' dangling ends on the core helices AUGCAU at various Na+ concentrations are reported. The results show that all 3' dangling ends except 3'U dangling at low Na+ concentrations can stabilize the helix and this stabilization is very sequence dependent. 相似文献
2.
We isolated five polymorphic microsatellite loci from the drepanosiphid aphid Tuberculatus quercicola (Matsumura) that is associated with the Daimyo oak, Quercus dentata Thunberg, using the magnetic particles method. The isolated loci were polymorphic, with four to 16 alleles in 40 aphids. Expected heterozygosities ranged from 0.4 to 0.82. These loci can be used to quantify seasonal changes in clonal diversity in the metapopulation and the extent of clonal mixing in the colonies. 相似文献
3.
L F Tietze U Bothe U Griesbach M Nakaichi T Hasegawa H Nakamura Y Yamamoto 《Bioorganic & medicinal chemistry》2001,9(7):1747-1752
Distinct biological properties of the ortho-carboranyl (1,2-dicarba-closo-dodecaboranyl) glycosides 1, 2 and 3 were evaluated to estimate the suitability of these compounds for cancer treatment by boron neutron capture therapy. The boron uptake into B16-Melanoma cells was significantly higher by incubating the cells with aqueous solutions of carboranyl glucoside 1 (11.2 ppm after 3h), lactoside 2 (13.2 ppm after 12h) and maltoside 3 (20.0 ppm after 24h) compared with solutions of clinically used p-boronophenylalanine (BPA) 5 (3.1 ppm after 24h). Carboranyl maltoside 3 was more effective than boron-10 enriched 5 in killing C-6 rat glioma cells by incubating the cells with the compound and subsequent treatment with thermal neutrons. 3 was also administrated iv, in concentrations of 25 mg boron/kg body weight to rats bearing brain tumors. After a period of 4h after administration the concentration of boron in the tumor tissue was 3.0 ppm. 相似文献
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The aim of this study was to investigate the effects of the relaxation of the gluten network on pasta rehydration kinetics. The moisture content of pasta, under conditions where the effects of the diffusion of water on the moisture content were negligible, was estimated by extrapolating the average moisture content of pasta of various diameters to 0?mm. The moisture content of imaginary, infinitely thin pasta did not reach equilibrium even after 1?h of rehydration. The rehydration of pasta made of only gluten was also measured. The rate constants estimated by the Long and Richman equation for both the pasta indicated that the rehydration kinetics of infinitely thin pasta were similar to those of gluten pasta. These results suggest that the swelling of starch by fast gelatinization was restricted by the honeycomb structural network of gluten and the relaxation of the gluten network controlled pasta rehydration kinetics. 相似文献
6.
Toshisada Suzuki Kaori Tomita-Yokotani Hirokazu Tsubura Shigeki Yoshida Isao Kusakabe Kosumi Yamada Yoichi Miki Koji Hasegawa 《Bioresource technology》2002,81(2):91-96
Tomato juice waste was hydrolyzed with acid. Tomato juice waste (500 g; wet weight) was heated with 0.5 N HCl (2.5 l) at 70 degrees C for 4 h. After neutralization, the growth-promoting extracts (300 g; dry weight) in the plants were produced from the tomato waste. The acid extract significantly promoted the growth of cockscomb (Celosia argentea L.) and tomato (Lycopersicon esculentum L.) seedlings. We have recognized potent plant growth-promoting substances in the acid extract from tomato waste. The most effective components in the active fraction were almost all oligogalacturonic acids (DP 6-12). This paper is the first report that plant growth-promoting oligosaccharides can be directly produced from tomato juice waste. It is possible that the substances from the tomato waste can become useful plant growth regulators in the agriculture field in the future. 相似文献
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Nobukazu Suganuma Satoru Ito Hiromichi Aso Masashi Kondo Mitsuo Sato Masahiro Sokabe Yoshinori Hasegawa 《PloS one》2012,7(9)
It is suggested that migration of airway smooth muscle (ASM) cells plays an important role in the pathogenesis of airway remodeling in asthma. Increases in intracellular Ca2+ concentrations ([Ca2+]i) regulate most ASM cell functions related to asthma, such as contraction and proliferation. Recently, STIM1 was identified as a sarcoplasmic reticulum (SR) Ca2+ sensor that activates Orai1, the Ca2+ channel responsible for store-operated Ca2+ entry (SOCE). We investigated the role of STIM1 in [Ca2+]i and cell migration induced by platelet-derived growth factor (PDGF)-BB in human ASM cells. Cell migration was assessed by a chemotaxis chamber assay. Human ASM cells express STIM1, STIM2, and Orai1 mRNAs. SOCE activated by thapsigargin, an inhibitor of SR Ca2+-ATPase, was significantly blocked by STIM1 siRNA and Orai1 siRNA but not by STIM2 siRNA. PDGF-BB induced a transient increase in [Ca2+]i followed by sustained [Ca2+]i elevation. Sustained increases in [Ca2+]i due to PDGF-BB were significantly inhibited by a Ca2+ chelating agent EGTA or by siRNA for STIM1 or Orai1. The numbers of migrating cells were significantly increased by PDGF-BB treatment for 6 h. Knockdown of STIM1 and Orai1 by siRNA transfection inhibited PDGF-induced cell migration. Similarly, EGTA significantly inhibited PDGF-induced cell migration. In contrast, transfection with siRNA for STIM2 did not inhibit the sustained elevation of [Ca2+]i or cell migration induced by PDGF-BB. These results demonstrate that STIM1 and Orai1 are essential for PDGF-induced cell migration and Ca2+ influx in human ASM cells. STIM1 could be an important molecule responsible for airway remodeling. 相似文献
10.
Betamethasone 17, 21-dipropionate (BMDP), a potent glucocorticoid, produces adrenal hypertrophy in the rat fetus. The present study was performed to investigate the possible alterations of corticosteroidogenesis due to endogeneous substrates or exogenous pregnenolone in the incubation of homogenates of fetal hypertrophic adrenals caused by BMDP given to pregnant rats at day 19 of pregnancy.The corticosteroidal products and those levels per mg homogenate in an incubate of the hypertrophic adrenal homogenate did not differ from those of a normal adrenal. No accumulations of abnormal precursors or intermediates were found in the incubates of the hypertrophic adrenals. It is concluded from these findings that no qualitative alterations in the pathway of corticosteroidogenesis occurred in the hypertrophic adrenal glands caused by BMDP in the rat fetus. When the calculation was done per adrenal gland, the content of corticosterone in the incubate of the homogenate of the hypertrophic adrenal was remarkably higher than that found in a normal gland. This finding was compatible with the significant increase of the plasma corticosterone concentration in the fetuses with the adrenal hypertrophy caused by BMDP. 相似文献