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101.
102.
Complete mRNA sequence of transferrin from Galleria mellonella was obtained, and compared with those of other species. Until now, two types of insect transferrin were reported. Transferrins in cockroach and termite have two iron binding sites while those in most other insect groups, studied for the protein, have only one. It was suggested that the presence of two types of transferrin was related with transferrin evolution, because vertebrate transferrins have two iron binding sites, called N and C terminal lobe. It was shown that G. mellonella transferrin also has only one iron binding site (N terminal lobe), and the deduced amino acid sequence was most similar to those of Manduca sexta and Bombyx mori. 相似文献
103.
First finding of a quarantine pest,Atherigona (Acritochaeta) orientalis Schiner (Diptera: Muscidae), in Korea 下载免费PDF全文
The invasive quarantine pest fly, Atherigona (Acritochaeta) orientalis Schiner, is observed for the first time in tomato greenhouses in Gyeongsangbuk‐do, Korea. The genus Atherigona Rondani is also newly added to Korean fauna. Allium tuberosum is listed as a new host crop for this species. Some morphological characteristics for accurate identification and host lists are given to provide plant quarantine information for pest management. 相似文献
104.
浦东滩涂中型土壤动物群落结构及土质酸碱度生物评价分析 总被引:14,自引:2,他引:14
1999年,对上海浦东滩涂4类不同酸碱度土壤中的中型土壤动物进行了调查。应用物种丰富度,个体数多度,多样性指数和均匀度4个群落参数,并结合种类研究,讨论了土壤动物群落结构与不同酸碱度土壤的关系。结果表明,土壤中弹尾目和蜱螨目对不同酸碱度土壤反应敏感。弹尾目的3个群落参数和蜱螨目的4个参数均很好地反映与土壤反应敏感。弹尾目的3个群落参数和蜱螨目的4个参数均很好地反映与土壤pH的关系,相关系数分别在0.9以上和0.85左右,在pH相差较大的情况下,可以区分不同酸碱度的土壤。弹尾目的符Tao(Paranura sp.)可用于评价酸碱度较接近的土壤,球角Tao(Hypogastrura sp.)可用于评价酸碱度相差较大,高pH或环境条件较恶劣的土壤。 相似文献
105.
Jehun Choi Sung Jin Bae Young Mi Ha Jae Kyung No Eun Kyeong Lee Jun Sik Lee Suhee Song Hyojin Lee Hongsuk Suh Byung Pal Yu Hae Young Chung 《Bioorganic & medicinal chemistry letters》2010,20(16):4882-4884
In searching for new agents with a depigmenting effect, we synthesized a derivative of resveratrol, 5-(6-hydroxy-2-naphthyl)-1,2,3-benzenetriol (5HNB) with a potent tyrosinase inhibitory activity. 5HNB inhibited mushroom tyrosinase with an IC50 value of 2.95 μM, which is more potent than the well-known anti-tyrosinase activity of kojic acid (IC50 = 38.24). The results of the enzymatic inhibition kinetics by Lineweaver–Burk analysis indicated 5HNB inhibits tyrosinase non-competitively when l-tyrosine was used as the substrate. Based on the strong inhibitory action of 5HNB, it is expected that 5HNB can suppress melanin production in which tyrosinase plays the essential role. Our expectation was confirmed by the experimentations with B16 melanoma cells in which 5HNB inhibited melanin production. We propose that 5HNB might have skin-whitening effects as well as therapeutic potential for treating skin pigmentation disorders. 相似文献
106.
Young Ae Yoon Dong Hoon Kim Byoung Moon Lee Tae Kyun Kim Myung Hun Cha Jae Young Sim Jae Gyu Kim 《Bioorganic & medicinal chemistry letters》2010,20(17):5237-5240
A series of 1H-pyrrolo[2,3-c]pyridines as acid pump antagonists (APAs) was synthesized and the inhibitory activities against H+/K+ ATPase isolated from hog gastric mucosa were determined. After elaborating on substituents at N1, C5, and C7 position of 1H-pyrrolo[2,3-c]pyridine scaffold, we have observed that compounds 14f and 14g are potent APAs with H+/K+ ATPase IC50 = 28 and 29 nM, respectively. 相似文献
107.
Dong Soo Kim Yoon Kwon Nam Jae Koo Noh Chul Hong Park Frank A. Chapman 《Ichthyological Research》2005,52(1):94-97
The shortnose sturgeon Acipenser brevirostrum was revealed to have a larger number of chromosomes than previously reported for other sturgeon species. Its chromosome number ranged from 362 to 372 (of ten specimens examined), showing intraindividual variation. The karyotype of metaphase with the highest chromosome number (372) consisted of 89 pairs of macrochromosomes and 97 pairs of microchromosomes (fundamental number; NF=550). Although the microchromosomes were relatively shorter than the macrochromosomes, most of them had discernible arms and centromeres. Silver-stained nucleolar organizer regions (Ag-NORs) were localized on the telomeric regions of 5 pairs of chromosomes (Ag-NORs=10): 4 were made up of small meta/submetacentrics and 1 of acrocentrics. Polyploidy of A. brevirostrum should be hexaploid based on the karyotype, numerous chromosomes, Ag-NORs, and previously reported large genome size (ca. 13pg DNA/cell).Supplementary material to this paper is available in electronic format at http://dx.doi.org/10.1007/s10228-004-0257-z 相似文献
108.
Jaeyoon Kim Yoon Sup Choi Seyoung Lim Kyungmoo Yea Jong Hyuk Yoon Dong‐Jae Jun Sang Hoon Ha Jung‐Wook Kim Jae Ho Kim Pann‐Ghill Suh Sung Ho Ryu Taehoon G. Lee 《Proteomics》2010,10(3):394-405
Adipogenesis is a complex process that is accompanied by a number of molecular events. In this study, a proteomic approach was adopted to identify secretory factors associated with adipogenesis. A label‐free shotgun proteomic strategy was implemented to analyze proteins secreted by human adipose stromal vascular fraction cells and differentiated adipocytes. A total of 474 proteins were finally identified and classified according to quantitative changes and statistical significances. Briefly, 177 proteins were significantly upregulated during adipogenesis (Class I), whereas 60 proteins were significantly downregulated (Class II). Changes in the expressions of several proteins were confirmed by quantitative RT‐PCR and immunoblotting. One obvious finding based on proteomic data was that the amounts of several extracellular modulators of Wnt and transforming growth factor‐β (TGF‐β) signaling changed during adipogenesis. The expressions of secreted frizzled‐related proteins, dickkopf‐related proteins, and latent TGF‐β‐binding proteins were found to be altered during adipogenesis, which suggests that they participate in the fine regulation of Wnt and TGF‐β signaling. This study provides useful tools and important clues regarding the roles of secretory factors during adipogenic differentiation, and provides information related to obesity and obesity‐related metabolic diseases. 相似文献
109.
The optimization of submerged culture conditions for mycelial growth and exopolysaccharide (EPS) production in an edible mushroom Tremella fuciformis was studied in shake flasks and bioreactors. The temperature of 28 degrees C and pH 8 in the beginning of fermentation in agitated flasks was the most efficient condition to obtain maximum mycelial biomass and EPS. The optimal medium constituents were as follows (gL(-1)): glucose 20, tryptone 2, KH(2)PO(4) 0.46, K(2)HPO(4) 1 and MgSO(4).7H(2)O 0.5. The fungus was cultivated under various agitation and aeration conditions in a 5L stirred-tank bioreactor. The maximum cell mass and EPS production were obtained at a relatively high agitation speed of 200 rpm and at an aeration rate of 2 vvm. The flow behavior of the fermentation broth was Newtonian and the maximum apparent viscosity (35 cP) was observed at a highly aerated condition (2 vvm). The EPS productivity in an airlift reactor was higher than that in the stirred-tank reactor. The morphological study revealed that the fungus grows in mainly three different yeast-like forms: ovoid, elongated, and double yeast forms. The high population of the elongated yeast has a very close relationship to high EPS production. The EPS were protein-bound polysaccharides consisted of mainly mannose, xylose, and fucose. The molecular weights of EPS were determined to be (1.3-1.5)x10(6). 相似文献
110.
Jeong HJ Park YD Park HY Jeong IY Jeong TS Lee WS 《Bioorganic & medicinal chemistry letters》2006,16(21):5576-5579
A series of multi-substituted oximes were prepared and their potencies for inhibiting lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) activity were evaluated in vitro. Among them, compounds 3a, 3b, and 3m were identified to display a micromolar potency for inhibiting Lp-PLA(2) in whole human plasma and isolated human LDL. Based on these results, structure-activity relationship was studied on modification of three parts of R(1), R(2), and R(3) to identify a potent pharmacophore for Lp-PLA(2). In an attempt to introduce various functional groups at R(2) and R(3), we discovered that replacement of less lipophilic groups led to an increase of inhibitory activity. Among the tested oxime derivatives, cyano- and morpholino-substituted analogue 4f at R(2) and R(3) had the highest potency with an IC(50) value of 0.05 microM in whole human plasma. 相似文献