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241.
Young June Lee 《Journal of Asia》2012,15(2):307-309
Pomponia bullata Schmidt, 1924 stat. rev. from Java is resurrected from junior synonymy with Pomponia picta (Walker, 1870) from Sumatra and redescribed. The only male specimen out of three syntypes is designated as the lectotype. 相似文献
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244.
Some β-d-hexopyranosides of 1-thio-d-glucose, 2-acetamido-2-deoxy-1-thio-d-glucose, and 1-thio-d-galactose were examined by laser-Raman spectroscopy. An anomeric CH bending vibration was found at 891 ± 7 cm-1 for all compounds investigated; thus, the anomers of these sugars can be differentiated by Raman spectroscopy. The N-acetyl group and carboxyl group can also be detected by Raman spectroscopy. Unlike protein samples, the carbohydrates in aqueous solution yield less useful information from Raman spectra than in the solid state; this is due to the extensive overlapping of carbohydrate OH bands with water OH bands. 相似文献
245.
Piao S Kim S Kim JH Park JW Lee BL Ha NC 《The Journal of biological chemistry》2007,282(14):10783-10791
A family of serine proteases (SPs) mediates the proteolytic cascades of embryonic development and immune response in invertebrates. These proteases, called easter-type SPs, consist of clip and chymotrypsin-like SP domains. The SP domain of easter-type proteases differs from those of typical SPs in its primary structure. Herein, we report the first crystal structure of the SP domain of easter-type proteases, presented as that of prophenoloxidase activating factor (PPAF)-I in zymogen form. This structure reveals several important structural features including a bound calcium ion, an additional loop with a unique disulfide linkage, a canyon-like deep active site, and an exposed activation loop. We subsequently show the role of the bound calcium and the proteolytic susceptibility of the activation loop, which occurs in a clip domain-independent manner. Based on biochemical study in the presence of heparin, we suggest that PPAF-III, highly homologous to PPAF-I, contains a surface patch that is responsible for enhancing the catalytic activity through interaction with a nonsubstrate region of a target protein. These results provide insights into an activation mechanism of easter-type proteases in proteolytic cascades, in comparison with the well studied blood coagulation enzymes in mammals. 相似文献
246.
Duck‐Oung Jung Dae‐Sup Park Jae‐Kyoung Shim Sukchan Lee Jaeho Pyee Kyeong‐Yeoll Lee 《Entomological Research》2019,49(1):72-77
Mites are one of the serious pests of turfgrass. Our survey of turfgrass fields from 2013 to 2015 in Korea showed that the occurrence of leaf chlorotic symptom has gradually extended to at least 60% of the examined golf courses. We identified the zoysiae mite Aceria zoysiae in most damaged zoysiagrasses. Artificial infestation of A. zoysiae into zoysiagrasses in pots resulted in symptoms of chlorosis and marginal rolling of the leaves within 3 weeks. We firstly determined the nucleotide sequence of mitochondrial cytochrome c oxidase subunit I (COI) and internal transcribed spacer 2 (ITS2) of the nuclear ribosomal DNA region of A. zoysiae. The variations in COI and ITS2 between A. zoysiae and other species of the genus were 20.9%–43.0% and 7.5%–67.3%, respectively, suggesting significant genetic divergence within the genus. Our study provides valuable information for the rapid diagnosis and infestation monitoring of A. zoysiae in turfgrass fields. 相似文献
247.
Background
Extracting biological information from high-density Affymetrix arrays is a multi-step process that begins with the accurate annotation of microarray probes. Shortfalls in the original Affymetrix probe annotation have been described; however, few studies have provided rigorous solutions for routine data analysis. 相似文献248.
High Performance Flexible Supercapacitor Electrodes Composed of Ultralarge Graphene Sheets and Vanadium Dioxide 下载免费PDF全文
Little is known regarding the effect of the graphene lateral size on the electrochemical performance of hybrid graphene electrode. This work examines the electrochemical performance of a flexible hybrid supercapacitor electrode composed of ultralarge graphene oxide (UGO; mean lateral size of 47 ± 22 μm) and vanadium dioxide (VO2) nanobelts, referring to a reference electrode composed of small scale graphene oxide (SGO; mean lateral size of 0.8 ± 0.5 μm) and VO2.Thermal treatment converts UGO/VO2 and SGO/VO2 to URGO/VO2 (denoted VURGO) and SRGO/VO2 (denoted VSRGO) electrodes, respectively. The sheet resistance of the VURGO film (0.57 ± 0.03 kΩ sq.–1) was two orders of magnitude lower than that of the VSRGO (55.74 ± 9.35 kΩ sq.–1). The VURGO hybrid electrode showed a specific capacitance of 769 F g?1, which was significantly better than the corresponding values for the VSRGO electrode (385 F/g). These results support the notion that the use of ultralarge graphene sheets (≈22 500 μm2) lowers the intersheet resistance due to the presence of fewer intersheet tunneling barriers. This article highlights the potential utility of URGO (as a conductive support) in hybrid electrode containing VO2 nanobelts for high performance flexible hybrid supercapacitor. 相似文献
249.
Schizophyllan (SPG)-treated macrophages and anti-tumor activities against syngeneic and allogeneic tumor cells 总被引:1,自引:0,他引:1
We tested anti-tumor activities of macrophages treated with a neutral polysaccharide, schizophyllan (SPG), against syngeneic and allogeneic tumor cell lines. SPG was a macrophage stimulant which was not mitogenic to lymphocytes. That made a sharp contrast with the data that Corynebacterium parvum, BCG, and muramyl dipeptide (MDF) were macrophage stimulants which had lymphocyte-activating properties. Treatment of SPG-treated PEC with Thy12 monoclonal antibody and guinea pig complement did not affect the capabilities of tumor-cell-growth suppression by the treated PEC. Thus, the effector cells were peritoneal adherent cells (macrophages morphologically) and effector-to-target contact seemed to be necessary for effective tumor-cell-growth inhibition, although contradictory data exist for this. Murine peritoneal adherent cells harvested 4 days after a single IP injection of SPG at a dose of 100 mg/kg body weight of mouse showed the most prominent cytostatic and cytotoxic activities against syngeneic and allogeneic tumor cells. The distribution of anti-tumor activity in macrophages of various sizes followed the same pattern as macrophages treated with C. Parvum, i.e., larger macrophages showed more remarkable anti-tumor activity. Crude nonadherent peritoneal cells incubated with SPG at a concentration of 10 micrograms/ml, 100 micrograms/ml, or 1 mg/ml did not secrete lymphokine that rendered macrophages cytotoxic, while ConA-treated nonadherent cells did so. Furthermore, spleen cells treated with SPG in vivo did not secrete macrophage-activating lymphokine in the presence of SPG. On the other hand, addition of 1 mg/ml of SPG-treated peritoneal adherent cells and bone-marrow-derived macrophages in vitro rendered them cytotoxic to a moderate degree. This implies that SPG may activate macrophages directly, allowing them to become cytotoxic in the peritoneal cavity. Lastly, SPG could induce production of II-1-like factor to a moderate degree. SPG, whose molecular structure is well elucidated, will provide us with a strong tool to analyze the mechanism of macrophage activation both in vitro and in vivo. 相似文献
250.
Kim TS Hague AB Lee TI Lian B Tegley CM Wang X Burgess TL Qian YX Ross S Tagari P Lin CH Mayeda C Dao J Jordan S Mohr C Cheetham J Viswanadhan V Tasker AS 《Bioorganic & medicinal chemistry letters》2004,14(1):87-90
A series of (4-piperidinylphenyl)aminoethyl amides based on dipeptide anilines were synthesized and tested against cathepsin K, cathepsin L and cathepsin B. These new non-covalent inhibitors exhibited single-digit nM inhibition of the cysteine proteases. Compounds 3 and 7 demonstrated potency in both mouse and human osteoclast resorption assays. 相似文献