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排序方式: 共有575条查询结果,搜索用时 31 毫秒
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P J Robinson R R Schellenberg Y Wakai J Road P D Paré 《Journal of applied physiology》2004,96(3):1063-1068
Canine trachealis muscle will shorten by 70% of resting length when maximally stimulated in vitro. In contrast, trachealis muscle will shorten by only 30-40% when stimulated in vivo. To examine the possibility that an elastic load applied by the tracheal cartilage contributes to the in vivo limitation of shortening, single pairs of sonomicrometry crystals were inserted into the trachealis muscle at the level of the fifth cartilage ring in five dogs. The segment containing the crystals was then excised and mounted on a tension-testing apparatus. Points on the active length-tension curve and the passive length-tension relation of the cartilage only were determined. The preload applied to the muscle before contraction varied from 10 to 40 g (mean 21 +/- 4 g). The afterload applied by the cartilage during trachealis contraction ranged from 13 to 56 g (30 +/- 6 g). The calculated elastic afterloads were substantial and appeared to be sufficient to explain the degree of shortening observed in four of the seven rings; in the remaining three rings, the limitation of shortening was greater than would be expected from the elastic load provided by the cartilage. Additional sources of loading and/or additional mechanisms may contribute to limited in situ shortening. In summary, tracheal cartilage applies a preload and an elastic afterload to the trachealis that are substantial and contribute to the limitation of trachealis muscle shortening in vivo. 相似文献
3.
Suka Asako Oki Hiroya Kato Yuki Kawahara Kazuki Ohkubo Tadayasu Maruno Takahiro Kobayashi Yuji Fujii Sotaro Wakai Satoshi Lisdiana Lisa Sambongi Yoshihiro 《Extremophiles : life under extreme conditions》2019,23(2):239-248
Extremophiles - The stability of dimeric cytochrome c′ from a thermophile, as compared with that of a homologous mesophilic counterpart, is attributed to strengthened interactions around the... 相似文献
4.
Ehlinger Claire Dartevelle Pauline Zaet Abdurraouf Kurashige Yoshihito Haïkel Youssef Metz-Boutigue Marie-Hélène Marban Céline 《International journal of peptide research and therapeutics》2019,25(4):1679-1687
International Journal of Peptide Research and Therapeutics - The success of endodontic treatments depends on the elimination of intracanal pathogens. Since irrigation and instrumentation can only... 相似文献
5.
Akash Chandela Taeko Watanabe Kenji Yamagishi Yoshihito Ueno 《Bioorganic & medicinal chemistry》2019,27(7):1341-1349
With the aim to create a small interfering RNA (siRNA) with enhanced activity and resistance to nuclease degradation, we synthesized and evaluated the properties of the following siRNAs containing haloalkyl β-d-ribofuranosides at their 3′-dangling ends: 2,2,2-trifluoroethyl β-d-ribofuranoside, 2,2,2-trichloroethyl β-d-ribofuranoside and 2,2,2-tribromoethyl β-d-ribofuranoside. The gene silencing activities of the modified siRNAs were investigated through a dual luciferase reporter assay using HeLa cells. The highest silencing activity was observed for the trichloroethyl analog modified siRNA, which was closely followed by the trifluoroethyl and tribromoethyl analogs. The modified siRNAs were found to show increased binding affinity towards the Piwi-Argonaute-Zwille (PAZ) domain protein based on computational analysis and an experimental study. Furthermore, the RNAs modified with the analogs at their 3′-ends exhibited improved resistance to hydrolysis by a 3′-exonuclease. 相似文献
6.
A new species of Amphidinium, A. cupulatisquama Tamura et Horiguchi, from sand samples from Ikei Island, Okinawa Prefecture in subtropical Japan, is described based on light, scanning and transmission electron microscopy and the partial sequencing of the large subunit rDNA gene. The species has a typical morphology for the genus, but is distinguished from previously described species by having a combination of the following characteristics: (i) a relatively large cell (over 30 µm in length); (ii) possessing an eyespot on the dorsal side of the cingulum; (iii) the longitudinal flagellum emerging from a point close to the cingulum; (iv) cell division taking place in the motile phase; and (v) possessing body scales. This is the third species of this genus to possess body scales. The body scales of A. cupulatisquama are uniform and cup‐shaped in side view and elliptical in face view. Their dimensions are 136.4 nm by 91.0 nm by 81.8 nm high. In side view, the scale is seen to have a thick lower half and a thin upper half. This scale type is very different from those of previously reported Amphidinium species (HG114 and HG115). The molecular tree indicated that A. cupulatisquama and the two other strains of body scale‐bearing Amphidinium are distantly related within the Amphidinium clade. 相似文献
7.
Veerle Vanderheyden Takuya Wakai Geert Bultynck Humbert De Smedt Jan B. Parys Rafael A. Fissore 《Cell calcium》2009,46(1):56-64
Egg activation and further embryo development require a sperm-induced intracellular Ca2+ signal at the time of fertilization. Prior to fertilization, the egg's Ca2+ machinery is therefore optimized. To this end, during oocyte maturation, the sensitivity, i.e. the Ca2+ releasing ability, of the inositol 1,4,5-trisphosphate receptor type 1 (IP3R1), which is responsible for most of this Ca2+ release, markedly increases. In this study, the recently discovered specific Polo-like kinase (Plk) inhibitor BI2536 was used to investigate the role of Plk1 in this process. BI2536 inactivates Plk1 in oocytes at the early stages of maturation and significantly decreases IP3R1 phosphorylation at an MPM-2 epitope at this stage. Moreover, this decrease in Plk1-dependent MPM-2 phosphorylation significantly lowers IP3R1 sensitivity. Finally, using in vitro phosphorylation techniques we identified T2656 as a major Plk1 site on IP3R1. We therefore propose that the initial increase in IP3R1 sensitivity during oocyte maturation is underpinned by IP3R1 phosphorylation at an MPM-2 epitope(s). 相似文献
8.
Takuya Koseki Akane Hori Shouji Seki Tetsuya Murayama Yoshihito Shiono 《Applied microbiology and biotechnology》2009,83(4):689-696
Two hypothetical proteins XP_001818628 and XP_001819091 (designated AoFaeB and AoFaeC, respectively), showing sequence identity
with known type-C feruloyl esterases, have been found in the genomic sequence of Aspergillus oryzae. We cloned the putative A. oryzae feruloyl esterase-encoding genes and expressed them in Pichia pastoris. Both purified recombinant AoFaeB (rAoFaeB) and AoFaeC (rAoFaeC) had apparent relative molecular masses of 61,000 and 75,000,
respectively, on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. After N-deglycosylation, both proteins had a relative molecular mass of 55,000. The optimum pH for rAoFaeB was 6.0, although it was
stable at pH values ranging from 3.0 to 9.0; rAoFaeC had an optimum pH of 6.0 and was stable in the pH range of 7.0–10.0.
Thermostability of rAoFaeC was greater than that of rAoFaeB. Whereas rAoFaeC displayed hydrolytic activity toward methyl caffeate,
methyl p-coumarate, methyl ferulate, and methyl sinapate, rAoFaeB displayed hydrolytic activity toward methyl caffeate, methyl p-coumarate, and methyl ferulate but not toward methyl sinapate. Substrate specificity profiling of rAoFaeB and rAoFaeC revealed
type-B and type-C feruloyl esterases, respectively. Ferulic acid was efficiently released from wheat arabinoxylan when both
esterases were applied with xylanase from Thermomyces lanuginosus. Both recombinant proteins also exhibited hydrolytic activity toward chlorogenic acid.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
9.
Kedong Ma Minato Wakisaka Kenji Sakai Yoshihito Shirai 《Bioresource technology》2009,100(7):2289-2292
A stable mutant flocculent yeast strain of Saccharomyces cerevisiae KRM-1 was isolated during repeated-batch ethanol fermentation using kitchen refuse as the medium. The mechanism of flocculation and interaction with the medium was investigated. According to sugar inhibition assay, it was found that the mutant flocculent strain was a NewFlo phenotype. Flocculation was completely inhibited by protease, proteinase K and partially reduced by treatments with carbohydrate-hydrolyzing enzymes. Flocculation ability showed no difference for pH 3.0–6.0. Furthermore, the mutant flocculent yeast provided repeated-batch cultivations employing cell recycles by flocculation over 10 rounds of cultivation for the production of ethanol from kitchen refuse medium, resulting in relatively high productivity averaging 8.25 g/L/h over 10 batches and with a maximal of 10.08 g/L/h in the final batch. Cell recycle by flocculation was fast and convenient, and could therefore be applicable for industrial-scale ethanol production. 相似文献
10.
The application of the mutated acetolactate synthase gene from rice as the selectable marker gene in the production of transgenic soybeans 总被引:1,自引:0,他引:1
Makoto Tougou Noriko Yamagishi Noriyuki Furutani Koichiro Kaku Tsutomu Shimizu Yoshihito Takahata Jun-ichi Sakai Seiji Kanematsu Soh Hidaka 《Plant cell reports》2009,28(5):769-776
We investigated selective culturing conditions for the production of transgenic soybeans. In this culturing system, we used
the acetolactate synthase (ALS)-inhibiting herbicide-resistance gene derived from rice (Os-mALS gene) as a selectable marker gene instead of that derived from bacteria, which interfered with the cultivation and practical
usage of transgenic crops. T1 soybeans grown from one regenerated plant after selection of the ALS-targeting pyrimidinyl carboxy (PC) herbicide bispyribac-sodium
(BS) exhibited herbicide resistance, and the introduction and expression of the Os-mALS gene were confirmed by genetic analysis. The selective culturing system promoted by BS herbicide, in which the Os-mALS gene was used as a selectable marker, was proved to be applicable to the production of transgenic soybeans, despite the appearance
of escaped soybean plants that did not contain the Os-mALS transgene. 相似文献