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利用柱色谱从异柱五加 (Acanthopanax sieboldianus forma albeofolium Yook) 叶的甲醇提取液中分离出四个齐墩果烷型皂苷类化合物.通过波谱方法(1H NMR、13C NMR、2D NMR和FAB-MS)鉴定它们分别为kalopanax-saponin B (1)、acanthopanax saponin CP3(2)、kalopanax-saponin A (3) 和sieboldianoside A (4). 相似文献
423.
EFFECTS OF FORGETTING ON PERFORMANCE ON VARIOUS INTENSITY SCALING PROTOCOLS: MAGNITUDE ESTIMATION AND LABELED MAGNITUDE SCALE (GREEN SCALE) 总被引:1,自引:0,他引:1
Judges rated the intensity of NaCl solutions using magnitude estimation and the labeled magnitude scale. They performed under four response conditions that varied in reliance on memory: (1) verbal response, (2) written response with no retasting and the response sheet removed, (3) written response with a single response sheet which allowed past scores to be reviewed and amended but with no retasting, (4) the same as '3' but with retasting. Discrimination errors tended to decrease from conditions '1' through '4' yet the major and significant effect was allowing judges to retaste stimuli. The effects of how forgetting lowered discrimination were discussed in the context of experimental design and the absolute versus relative cognitive models of scaling. 相似文献
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SUKYUNG KIM HOONHEE SEO MD ABDUR RAHIM HANIEH TAJDOZIAN YUN-SOOK KIM HO-YEON SONG 《Polish journal of microbiology》2021,70(3):345
Human vaginal microorganisms play an important role in maintaining good health throughout the human life cycle. An imbalance in the vaginal microbiota is associated with an increased risk of pelvic inflammatory disease (PID). This study aimed to characterize and compare vaginal microbial profiles of premenopausal Korean women with and without PID. 74 Korean premenopausal female vaginal samples were obtained; 33 were from healthy women (a control group) and 41 from PID patients. Vaginal fluid samples were collected from the vaginal wall and posterior cervix and then analyzed by 16S ribosomal ribonucleic acid (rRNA) gene-based amplicon sequencing. Results showed a significant difference between the vaginal microbial communities of the two groups (Jensen-Shannon, p = 0.014; Bray-Curtis, p = 0.009; Generalized UniFrac, p = 0.007; UniFrac, p = 0.008). Lactobacillus accounted for the highest percentage (61.0%) of the control group but was significantly decreased (34.9%) in PID patients; this was the most significant difference among all bacterial communities (p = 0.028, LDA effect size = 5.129). In addition, in the PID patient group, species diversity significantly increased (Simpson, p = 0.07) as the proportion of various pathogens increased evenly, resulting in a polymicrobial infection. Similarly, lactate, which constituted the highest percentage of the organic acids in the control group, was significantly decreased in the PID patient group (p = 0.04). The present study’s findings will help understand PID from the microbiome perspective and are expected to contribute to the development of more efficient PID diagnosis and treatment modalities. 相似文献
426.
Yowhan?SONEmail author In Hyeop?PARK Myong Jong?YI Hyun O?JIN Dong Yeob?KIM Rae Hyun?KIM Jung Ok?HWANG 《Ecological Research》2004,19(1):21-28
Biomass, production, and nutrient distribution of a pure Quercus variabilis Bl. stand (stand 1) and two mixed Q. variabilis–Q. mongolica Fisch. stands (stand 2 and 3) were investigated in central Korea. Stand 1 naturally occurred on a site with a southern aspect while stand 2 and stand 3 occurred on sites with a northern aspect. Total (overstory+understory vegetation) biomass (tha-1) and annual production (tha–1year–1) were 137.8 and 11.1 for stand 1, 216.2 and 16.6 for stand 2, and 253.3 and 19.7 for stand 3. Nutrient contents (kgha–1) in the vegetation were distributed as follows: K, 478–860; N, 471–839; Ca, 428–791; Mg, 72–125; Na, 77–141; and P, 37–71, and were greatest in stand 3 followed by stand 2, and stand 1. Stand density influenced the differences in biomass, annual production and nutrient contents in the vegetation. Forest floor dry mass and N content (kgha–1) were 13400 and 169 for stand 1, 10400 and 133 for stand 2, and 11200 and 127 for stand 3. Total amounts of N, P and Na in the ecosystem were greatest in the upper 40cm of mineral soil followed by the vegetation and forest floor. However, the vegetation contained a greater amount of K than the mineral soil. It appeared that microenvironments, such as, aspect influenced the distribution of natural oak species within a relatively small area and resulted in differences in biomass, production and nutrient distribution among the stands. 相似文献
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In the present study, we report the 16 823‐bp long complete mitochondrial genome (mitogenome) of a carabid beetle, Damaster mirabilissimus mirabilissim (Coleoptera: Carabidae), which is endangered in Korea. The gene arrangement of D. m. mirabilissim mitogenome is identical to the most common type found in insects. The start codon of the D. m. mirabilissim COI gene is a typical ATN codon. On the other hand, the initiation codon for ND1 gene is TTG, instead of ATN. All transfer RNAs (tRNAs) exhibit a stable canonical clover‐leaf structure, except for tRNASer(AGN), the dihydrouridine arm of which forms a simple loop. The 1703‐bp long A+T‐rich region is the second longest among the complete adephagan mitogenome sequences, next to Macrogyrus oblongus belonging to Gyrinoidea. One of the unusual features of the genome is the presence of a tRNALeu(UUR)‐like sequence in the A+T‐rich region. This sequence displays the proper anticodon sequence and the potential to form secondary structures, but also harbors many mismatches in the stems. 相似文献
429.
目的:研究冬凌草甲素(ORI)对人结肠癌细胞株HCT116生长的影响及其可能机制。方法:以体外培养的HCT116细胞为研究对象,给予不同浓度(0、2.5、5、10、20μM)ORI处理HCT116细胞不同时间(0、24、48、72 h),通过MTT法检测其对HCT116细胞增殖的影响,DAPI染色观察其对细胞核的形态的影响,western blot检测细胞内β-catenin、c-myc蛋白表达的变化。结果:1ORI可显著抑制HCT116细胞的增殖,且此作用随着浓度和作用时间的增加或延长而增强(P〈0.05)。2ORI处理HCT116细胞24小时后,细胞核固缩的百分率随药物作用浓度的增加而增加。35、10、20μM ORI处理HCT116细胞24小时后,细胞内的β-catenin、c-myc蛋白水平均显著下调,且随着ORI浓度的增加逐渐减少。结论:ORI能以浓度和时间依赖性的方式抑制HCT116细胞的增殖,其机制可能与Wnt/β-catenin信号通路有关。 相似文献
430.