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排序方式: 共有165条查询结果,搜索用时 515 毫秒
1.
目的 研究药用植物广藿香Pogostemon cablin内生真菌撕裂耙齿菌Irpex laceratus A878的活性次级代谢产物。方法 运用硅胶、Sephadex LH-20、HPLC等多种柱色谱技术以及重结晶方法对发酵产物进行分离纯化,并利用1H-和13C-NMR、UV等谱学方法鉴定化合物结构。采用SRB法和Griess法测定化合物的生物活性。结果 从广藿香内生真菌撕裂耙齿菌A878固体发酵产物中分离鉴定了2个新化合物和10个已知化合物。分别为撕裂耙齿菌内酯A(1)、撕裂耙齿菌内酯B(2)、细胞松弛素H(3)、细胞松弛素J(4)、18-甲氧基细胞松弛素J(5)、去乙酰基细胞松弛素H(6)、细胞松弛素J3(7)、拟茎点霉(口山)酮A(8)、狄瑟酚A(9)、桔青霉三酚A(10)、(22E,24R)-麦角甾-5,7,22-三烯-3β-醇(11)和1S,2R,4S-三羟基-对-薄荷烷(12)。结论 化合物1、2为新的吡喃内酯类化合物。活性研究表明化合物4、5和9对人神经癌SF-268细胞、人乳腺癌MCF-7细胞、人肝癌H... 相似文献
2.
The evolution, epidemiology and zoonotic aspects of Sapoviruses (SaV) are still not well explored. In this study, we applied high-resolution phylogeny to investigate the epidemiological and zoonotic origins as well as taxonomic classification of animal and human SaV. Bayesian framework analyses showed an increase in porcine SaV (PoSaV) population dynamics and genetic diversity between 1975 and 1982, resulting in a SaV gene flow and generation of new strains among porcine and human populations. Our results also show the contribution of different animal populations involved in SaV epidemiology and highlight zoonotic aspects, as exemplified by the crucial role that swine, dogs, mink and humans play in SaV spread. Additionally, phylogenetic analysis suggests that bats may play key role in SaV epidemiology. According to our hypothesis, these animals may act as reservoirs or intermediate host species, contributing to viral spread in zoonotic and other epidemiological scenarios and facilitating the generation of new SaV genogroups and genotypes through recombination events. Data from large-scale phylogeny partition based on patristic distance, did not show a correlation between transmission clusters on generation of SaV genogroups, nevertheless we present both important findings about SaV taxonomy and important considerations useful for further taxonomical studies. 相似文献
3.
Noroviruses (NoVs) are the primary cause of non-bacterial acute gastroenteritis worldwide. Most NoV infections are caused by GII.4, but GII.6 is also an important genotype with a long-term persistence in human populations. In this study, the complete genome sequence of a NoV strain GZ2010-L96 isolated in China was identified and analyzed phylogenetically. The viral genome comprised 7550 nucleotides, and its phylogenetic analysis revealed that the strain belonged to GII.6 genotype. All reported GII.6 NoV capsid protein sequences were also collected for comparative analysis, and GZ2010-L96 was clustered into GII.6-b with other 8 strains. Meanwhile, it was found that 53 spots on viral capsid showed subcluster specificity according to multiple alignments. Moreover, homologous modeling of GZ2010-L96 based on comparison with GII.4 VA387 strain showed a different antigen distribution pattern. In summary, the genome of the GII.6 strain GZ2010-L96 detected in China was extensively characterized, and phylogenetic analyses of GII.6 NoVs based on the capsid proteins may reveal a different evolution process from the predominant genotype GII.4. 相似文献
4.
A novel covalent triazine-based organic framework (CTF), SCAU-2, was fabricated and used as an adsorbent for the solid-phase extraction of fourteen kinds of sulfonamides (SAs) from meat. Another CTF, SCAU-1, was adopted as a comparison material, as it has a similar motif. A series of structural characterization steps was carried out on the synthesized materials and several parameters were investigated during the extraction process, including the amount of adsorbent, the dilution ratio, the pH of the sample, and the washing and elution solvents. After detection with UHPLC-Q/TOF-MS/MS, the results revealed that SCAU-2 showed high extraction efficiencies towards the selected SAs. The LOD values are from 0.05 to 0.54 ng g−1, and the recoveries are from 84.1% to 91.9%, with RSDs ranging from 3.2% to 4.8% for SCAU-2 when spiked at 50 ng g−1. The results demonstrated that the proposed method has good applicability for the determination of SAs in complicated samples.A novel triazine-based CTF and a comparison CTF were synthesized; both CTFs showed excellent extraction efficiencies towards fourteen kinds of sulfonamides in meat and could be promising materials for food sample pretreatment. 相似文献
5.
目的 探讨儿童孤独症发病的相关危险因素, 为孤独症的防治提供理论依据。方法 采用成组病例对照研究, 对165例孤独症儿童和320例正常对照组儿童, 采用自编的孤独症危险因素调查表收集相关危险因素、家庭一般情况等资料, 用χ2检验分析两组儿童之间危险因素的差异。结果 病例组母亲高生育年龄(≥35岁)、有人工流产史、母孕期抑郁情绪史、母孕期被动吸烟史及父亲内向所占比例较正常组高(P<0.05), 进一步进行Logistic 回归分析显示母高育龄、孕期抑郁情绪、孕期被动吸烟、有人工流产史以及父亲性格内向为孤独症的危险因素。结论 母亲高龄生育、有人工流产史、孕期抑郁情绪、孕期被动吸烟以及父亲性格内向均可使儿童孤独症发病风险增高。 相似文献
6.
Hong-Xin Liu Hai-Bo Tan Sai-Ni Li Yu-Chan Chen Hao-Hua Li Sheng-Xiang Qiu 《Journal of Asian natural products research》2019,21(7):696-701
Two new polyketide metabolites, the 12-membered macrolides 4-hydroxy-12-methyloxacyclododecane-2,5,6-trione (1) and 12-methyloxacyclododecane-2,5,6-trione (2), were isolated from the endophytic fungal strain Cladosprium colocasiae A801 of the plant Callistemon viminalis, together with five known derivatives. Their structures were fully characterized by means of detailed spectroscopic analysis for new structures, and in comparison with published data for known compounds. The antibacterial, cytotoxic, and α-glucosidase inhibitory activities of the new compounds 1 and 2 were evaluated. 相似文献
7.
Xiaofei Lv Yuan Zhang Fangfang Zeng Aihua Yin Ning Ye Haimei Ouyang Dan Feng Dan Li Wenhua Ling Xiaozhuang Zhang 《Clinical rheumatology》2014,33(12):1801-1805
Gout is a common metabolic disorder with high heritability. We tried to explore the association between rs2231142 and gout. We searched “rs2231142 or Q141K and gout” in four databases and scholar searching website until 1 June, 2013 and included data from 52,010 participants in meta-analysis and subgroup analysis. The T allele of rs2231142 was associated with increased gout susceptibility (odds ratio [OR] [95 % confidence interval (95 % CI)]?=?1.73 [1.55–1.91], P?0.001). It increased gout risk in Caucasians with OR (95 % CI)?=?1.68 (1.50–1.87), P?0.001; Asians with OR (95 % CI)?=?1.93 (1.54–2.31), P?0.001; Africans with OR (95 % CI)?=?1.76 (1.15–2.36), P?0.001; and New Zealand Pacific Islanders with OR (95 % CI)?=?2.94 (1.72–4.15), P?0.001, but not in New Zealand Maoris, with OR (95 % CI)?=?1.12 (0.57–1.67), P?=?0.061. No publish or other biases were observed. The T allele of rs2231142 was associated with increased risk of gout. 相似文献
8.
Junlin Wu Yunping Peng Xiaoyun Liu Wenmei Li Shixing Tang 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2014,59(2):267-271
Prompt and accurate diagnosis is necessary to start adequate treatment for different affecting species including P. falciparum and P. vivax. Here we described the Wondfo Rapid diagnostic Kit (Pf-HRP2/PAN-pLDH) for the detection of P. falciparum and pan-plasmodium in patient specimen by using a nano-gold immunochromatographic assay. Our rapid assay adapted nano-gold labeling techniques and the monoclonal antibodies (mAbs) against both histidine rich protein-2 (Pf HRP-2) of P. falciparum and pan plasmodium-specific pLDH (pan pLDH). The established two-antibody sandwich immunochromatographic assay could detect P. falciparum and pan-plasmodium. The sensitivity and specificity of Wondfo rapid diagnostic kit were determined by comparing with the “gold standard” of microscopic examination of blood smears. In this study1023 blood samples were collected from outpatient clinics in China and Burma, and detected by both Wondfo kit and microscopic examination. The detection sensitivity and specificity of Wondfo rapid diagnostic kit were 96.46% and 99.67% for P. falciparum (HRP2), 95.03% and 99.24% for pLDH, 96.83% and 99.74% for non-falciparum species, 96.70% and 99.74% for P. vivax, respectively. These results indicate that Wondfo rapid diagnostic assay may be useful for detecting P. falciparum and non-P. falciparum (especially P.v.) in patient specimen. 相似文献
9.
10.
目的观察复方邻苯二甲醛消毒液的杀菌效果。方法采用悬液定量杀菌试验和模拟现场试验进行了检测。结果以含5070mg/L邻苯二甲醛的复方消毒液作用1min和5min,对铜绿假单胞菌和金黄色葡萄球菌的杀灭率均为100%。以含5635mg/L邻苯二甲醛的复方消毒液作用3min,对白色念珠菌的杀灭率为100%;对枯草杆菌黑色变种芽孢作用60min,杀灭率为100%。含体积分数50%小牛血清对复方邻苯二甲醛消毒液杀菌效果有轻度影响。结论复方邻苯二甲醛消毒液对细菌繁殖体、真菌和细菌芽孢具有很好的杀灭作用,受有机干扰物影响小。 相似文献