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11.
ABSTRACT In a review of the horseflies of the Tabanus mandarinus species group in Korea, six species are recognized. Among them, Tabanus nipponicus is newly recorded from Korea. Keys, annotated check lists of domestic records, collection data, and photographs of T. nipponicus are provided.  相似文献   
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The effect of Hg treatment on hemolymph and tissue ferritin in the wax moth Galleria mellonella was examined by western blotting. At 48 h after feeding HgCl2, the level of hemolymph ferritin increased approximately 1.8‐fold over that of control insects that were not fed HgCl2, while there was a small increase in tissue ferritin. Time series experiments showed that tissue ferritin had a typically saturated pattern, with a maximum level from 24 to 72 h, although it decreased 12 h following HgCl2 feeding, while hemolymph ferritin first decreased but subsequently increased. Tissue ferritin in the fat body, gut and Malpighian tubules, the main tissues of ferritin expression, was upregulated over time following treatment with Hg, and in particular, tissue ferritin in the gut increased by a large amount at 12–48 h. The results suggest that in G. mellonella, the ferritin‐inducible mechanisms following treatment with HgCl2 are different for hemolymph and tissue ferritin, as are their biochemical properties.  相似文献   
14.
The larentiine genus Trichopteryx Hübner in Korea is reviewed. Nine species, including one newly recorded species, T. misera (Butler), are recognized. Diagnostic characters of each species with photographs of adults and genitalia are provided. A key to the Korean species is also given.  相似文献   
15.
Monoclonal antibodies were prepared against lysosomal membrane proteins of amoebae and used to follow lysosome-phagosome fusion after induced phagocytosis. The specificity of antibodies was checked by indirect immunofluorescence microscopy, immunoelectron microscopy, and localization of the antigen in subcellular fractions. The antibody-recognized proteins started to appear on the membranes of phagolysosomes about 5 min after phagocytosis as detected by indirect immunofluorescence, and the intensity of fluorescence increased for up to 1 h. Results of injection experiments in which purified antibodies had been injected into living cells and probed by indirect fluorescence indicated that the antigens were located on the cytoplasmic side of the lysosomal membranes. Lysosomes fuse with phagosomes on the one hand but not with non-fusible vesicles such as symbiosomes on the other. The results support the view that a membrane component(s) of non-fusible vesicles somehow prevents lysosomoes from fusing with them.  相似文献   
16.
The present study relates to a methanol extract of the seed coat of Ginkgo biloba, and tested particularly on the third instar larvae of Spodoptera exigua. The extract was found to have an inhibitory effect on the growth of the larvae besides bringing a change in the nutrient reserves in the body of the insect. Topical application of five different doses of the methanol extract resulted in a mortal effect to third instar larvae of S. exigua that is very much dependent on the dose as well as duration of exposure. Lower doses revealed lower mortality after 24 h of application. At doses of 1.00, 2.00, 4.00, 8.00 and 16.00 ng/larva, mortalities were 9.25, 26.07, 50.32, 56.28 and 92.44%, respectively. The dose for 50% mortality (LD50) of methanol extracts by applied by a topical method with 1 µL of acetone solution was 1.92 ng/larva. Nutrient reserves like protein, glycogen and lipid are known to regulate pupation and adult emergence. These reserves have been found to be lower in treated larvae, indicating the insecticidal role of methanol extracts from G. biloba against third instar larvae of S. exigua.  相似文献   
17.
目的:研究枳实提取物及其药效组分橙皮苷和新橙皮苷对氧化低密度脂蛋白(oxidized low density lipoprotein,Ox-LDL)损伤的人脐静脉内皮细胞(human umbilical vein endothelial cells line,HUVEC)细胞间黏附分子-1(intercellular adhesion molecule-1,ICAM-1)表达和一氧化氮(nitric oxide,NO)释放的影响。方法:体外培养HUVEC,50μg/mL ox-LDL制造HUVEC损伤模型。以MTS染色法检测细胞毒性确定用药浓度。细胞ELISA法测定细胞表面ICAM-1的含量,试剂盒测定细胞培养上清液中NO含量。结果:①枳实提取物小于等于2 mg/mL时,橙皮苷浓度小于等于0.03125 mg/mL时,新橙皮苷浓度小于等于0.25 mg/mL时,HUVEC存活率分别大于80%。②2.0 mg/mL和1.0 mg/mL两个浓度的枳实提取物、15.625μg/mL的橙皮苷和0.2500 mg/mL新橙皮苷对ox-LDL诱导的HUVEC的ICAM-1表达有显著抑制作用。③2.0 mg/mL枳实提取物显著提高ox-LDL诱导的HUVEC和正常HUVEC培养液中的NO含量;7.813μg/mL、15.625μg/mL和31.250μg/mL 3个浓度的橙皮苷能显著提高ox-LDL诱导的HUVEC培养液中的NO含量,31.250μg/mL的橙皮苷能促进正常HUVEC的NO释放;0.2500 mg/mL和0.1250 mg/mL 2个浓度的新橙皮苷能显著提高ox-LDL诱导的HUVEC培养液中的NO含量。结论:枳实提取物及其药效组分橙皮苷、新橙皮苷能抑制ox-LDL诱导的HUVEC的ICAM-1表达,促进ox-LDL诱导的HUVEC的NO释放。  相似文献   
18.
Hypocotyl segments ofEleutherococcus senticosuscultured on Murashigeand Skoog's (MS) medium with 4.5 µM2,4-D produced somaticembryos directly from the surface of explants without interveningcallus formation. When these somatic embryos were subculturedto the same MS medium with 4.5 µM2,4-D, friable embryogeniccalli were formed mainly from radicle tips of somatic embryos,but at a low frequency (5%). Selected embryogenic calli weremaintained on MS agar or liquid medium with 4.5 µM2,4-D.To induce somatic embryo development, embryogenic calli andcell clumps were transferred to MS medium lacking 2,4-D. Thefrequency of somatic embryo formation differed between culturetypes with 1570 embryos formed per Petri dish from callus cultureand 5514 embryos formed per flask from cell suspension cultures.Somatic embryos formed on agar medium had larger cotyledonsthan those of embryos formed in liquid medium. GA3treatmentwas necessary to induce germination from somatic embryos. Therate of plant conversion was 97% in somatic embryos from callusculture and 76% in embryos from liquid culture. Regeneratedplantlets were successfully acclimatized in the glasshouse.Copyright1999 Annals of Botany Company Eleutherococcus senticosus, micro propagation, somatic embryogenesis.  相似文献   
19.
ABSTRACT. A new ciliate, Trimyema koreanum n. sp., isolated from hypersaline water (salinity of 293‰) from a solar saltern in Korea, was investigated using live observation, protargol impregnation, and gene sequencing. Trimyema koreanum is about 30 × 13 μm in vivo, has usually 23 longitudinal ciliary rows forming two distinct ciliary girdles visible both in vivo and in protargol impregnation. A third indistinct ciliary girdle as well as a girdle of mucocysts is distinguishable only in impregnated cells. We suggest T. koreanum as a new species, differing from the most similar species, T. marinum, by the presence of two distinct ciliary girdles (T. marinum usually has six ciliary girdles clearly visible in living cells and three anterior spirals that encircle the cell completely). Although the number of known 18S rRNA sequences in the genus Trimyema was limited, the Trimyema group including T. koreanum forms a strong clade. The phylogenetic position confirms that the isolate belongs to the genus Trimyema and is different from previously sequenced species. Trimyema koreanum is able to consume both prokaryotes and small eukaryotes (specifically, the alga Dunaliella sp.).  相似文献   
20.
Lespedeza (tribe Desmodieae, Fabaceae) follows a disjunct distribution in eastern Asia and eastern North America. Phylogenetic relationships among its species and related taxa were inferred from nuclear ribosomal internal transcribed spacer (ITS) and plastid sequences (trnH‐psbA, psbK‐psbI, trnK‐matK and rpoC1). We examined 35 species of Lespedeza, two of Kummerowia and one of Campylotropis, the sole constituents of the Lespedeza group. An analysis of these data revealed that the genus Campylotropis is sister to the other two genera. However, we were unable to resolve the relationships between Kummerowia and Lespedeza in the strict consensus trees of parsimony analyses based on plastid and combined DNA data. In the genus Lespedeza, the Old World subgenus Macrolespedeza is monophyletic, whereas the transcontinental subgenus Lespedeza is paraphyletic. Monophyly of eastern Asian species and of North American species is strongly supported. Although inconsistent with the traditional classification, this phylogenetic finding is consistent with seedling morphology. Three subgroups recognized in subgenus Macrolespedeza were unresolved in our phylogenetic trees. An incongruence length difference (ILD) test indicated that the two partitions (nuclear ITS and plastid sequences) were significantly incongruent, perhaps because of hybridization between species in Lespedeza. Most of the primary clades of tribe Desmodieae are Asian, implying that the relatively few New World ones, such as those in Lespedeza, are more recently derived from Asia. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 164 , 221–235.  相似文献   
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