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721.
A new eubrachythoracid arthrodire, Simosteus tuberculatus gen. et sp. nov., is described from the Upper Devonian Gogo Formation of Western Australia and its structure and relationships are discussed. It is related to the trematosteids, leiosteids and hadrosteids on the evidence of 'fused' preorbital and postnasal bones.  相似文献   
722.
Developing a robust root system is crucial to plant survival and competition for soil resources. Here we report that the non‐specific phospholipase C5 (NPC5) and its derived lipid mediator diacylglycerol (DAG) mediate lateral root (LR) development during salt stress in Arabidopsis thaliana. T‐DNA knockout mutant npc5‐1 produced few to no LR under mild NaCl stress, whereas overexpression of NPC5 increased LR number. Roots of npc5‐1 contained a lower level of DAG than wild type, whereas NPC5 overexpressor exhibited an increase in DAG level. Application of DAG, but not phosphatidic acid, fully restored LR growth of npc5‐1 to that of wild type under NaCl stress. NPC5 expression was significantly induced in Arabidopsis seedlings treated with NaCl. Npc5‐1 was less responsive to auxin‐mediated root growth than the wild type. These results indicate that NPC5 mediates LR development in response to salt stress and suggest that DAG functions as a lipid mediator in the stress signalling.  相似文献   
723.
Eight species of the genus Macrosiphum Passerini 1860 (Sternorrhyncha: Aphididae) are recognized from the Korean Peninsula. A new species, Macrosiphum ( Macrosiphum ) paektusani n. sp., is described herein for apterous and alate viviparous females on Rosa marretii Lev. (Rosaceae). The taxonomic position of Macrosiphum ( Macrosiphum ) cornifoliae Shinji 1924, com. rev., is transferred from the genus Sitobion Mordvilko 1914 to its original position. Host plants of the Korean Macrosiphum are reviewed and the identification key to subgenera and species is also presented.  相似文献   
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726.
Staphylococcus aureus is currently a significant multidrug-resistant bacterium, causing severe healthcare-associated and community-acquired infections worldwide. The current antibiotic regimen against this pathogen is becoming ineffective due to resistance, in addition, they disrupt the normal microbiota. It highlights the urgent need for a pathogen-specific drug with high antibacterial efficacy against S. aureus. α-Viniferin, a bioactive phytochemical compound, has been reported to have excellent anti-Staphylococcus efficacy as a topical agent. However, so far, there were no clinical trials that have been conducted to elucidate its efficacy. The present study aimed to investigate the antibacterial efficacy of α-viniferin against S. aureus in a ten-day clinical trial. Based on the results, α-viniferin showed 50% minimum inhibitory concentrations (MIC50 values) of 7.8 μg/ml in culture broth medium. α-Viniferin was administered in the nares three times a day for ten days using a sterile cotton swab stick. Nasal swab specimens were collected before (0 days) and after finishing the trial (10th day), and then analyzed. In the culture and RT-PCR-based analysis, S. ureus was reduced significantly: 0.01. In addition, 16S ribosomal RNA-based amplicon sequencing analysis showed that S. aureus reduced from 51.03% to 23.99% at the genus level. RNA-seq analysis was also done to gain insights into molecular mechanisms of α-viniferin against S. aureus, which revealed that some gene groups were reduced in 5-fold FC cutoff at two times MIC conditions. The study results demonstrate α-viniferin as a potential S. aureus-specific drug candidate.  相似文献   
727.
ABSTRACT. A choreotrich ciliate collected in waters off Geoje Island, on the eastern coast of the South Sea of the southern coastal water of Korea was morphologically and biometrically investigated through observations of permanent preparations after protargol impregnations. Morphological data and ciliary patterns indicated that the ciliate should be identified as Strombidinopsis acuminata based on the number of somatic kineties. The vertical distribution of the population abundance was also examined in relation to environmental conditions: higher abundances occurred in surface water with higher temperature (22–23 °C), lower salinity (32 psu), and higher concentration (ca 10 μg/L) of chlorophyll a . The 18S rRNA gene of specimens from clonal cultures isolated from natural assemblages was sequenced. While this isolate of S. acuminata is closer to Strombidinopsis jeokjo (99.6–99.8%) than other isolates of S. acuminata (<99.0%), monophyly of S. acuminata was not rejected by the AU test. We discuss the discordance between morphological and molecular data for Strombidinopsis . In order to confirm the species level of the Strombidinopsis specimens, additional information is required based on genealogical analyses of multiple loci.  相似文献   
728.
Serological comparisons of the seed proteins of Flagellaria indica L., Joinvillea bomeensis Becc. and Hanguana malayanum Merr. were made in order to provide evidence for the systematic evaluation of these taxa. Lack of serological cross-reactivity suggests the placement of these genera in three separate monogeneric families, Flagellariaceae, Joinvilleaceae and Hanguanaceae. Additional serological analyses are needed to evaluate their systematic position in the monocotyledons.  相似文献   
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