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991.
We investigate how human fruit consumption affects the spread of the alien invasive Ziziphus mauritiana along road corridors in northern Zimbabwe. A field survey was conducted to identify and map Z. Mauritiana stems at 25 randomly located 6‐ha plots placed along two main roads connecting the Zambezi Valley to the Highveld region. The L‐function was used to test for evidence of significant spatial clustering of the stems. The inhomogeneous point model fitted by maximum likelihood was also applied to check whether distance from the road explains variation in the number of stems per unit area. Finally, a t test was executed on log‐transformed abundance data to test for significant differences in the mean number of saplings and adults between the Zambezi Valley and the Highveld. Results of the L‐function indicated that Z. mauritiana had a clustered and linear distribution along roads both in the Zambezi Valley and Highveld regions. Results of the t test showed that the mean number of saplings per plot in the Zambezi Valley (μ1 = 275) was three times higher than in the Highveld (μ2 = 78), with p < 0.01. The mean number of adult trees was also significantly higher in the Zambezi Valley than in the Highveld. 相似文献
992.
993.
994.
Paeoniae Radix Rubra (Chi-Shao in Chinese) and Paeoniae Radix Alba (Bai-Shao in Chinese) are two valuable traditional Chinese medicine (TCM) drugs, usually indicated for menstrual disorders and viral infections. Paeonia anomala subsp. anomala (Xinjiang-Shaoyao in Chinese) is taken as Chi-Shao substitute in Xinjiang, China. Due to the diverse growing conditions, there are some differences in chemical compositions of three TCM drugs. An UPLC fingerprint analysis with chemometric methods, including similarity analysis and hierarchical clustering analysis, was applied in the study. By virtue of UPLC-QTOF-MS, 29 components including 18 monoterpene glycosides, 5 galloyl glucoses and 6 phenolic compounds were simultaneously identified. It could be concluded that the UPLC-QTOF-MS combined with chemometric methods could efficiently identify the three TCM drugs, and was a powerful approach for the chemical profiling of three TCM drugs. The developed method provide an available approach for quality control of three TCM drugs. 相似文献
995.
In combination with phytochemical results, the pilot chemotaxonomy study on genus Hedysarum by using HPLC methods revealed differences between section Fruticosa and the three other sections Multicaulia, Obscura and Subacaulia, but there was a closer genetic relationship with Multicaulia and Subacaulia. Isoflavonoids and pterocarpans were proved to be the common constituents of genus Hedysarum, whereas pterocarpans, benzofurans, and coumestans were the characteristic constituents of section Fruticosa, and chalcones were the chemical markers of section Multicaulia and section Subacaulia. The present finding is consistent with the classical morphological classification of genus Hedysarum, and provides supporting evidences for dividing Hedysarum into two subgenera, i.e. subgenus Hedysara and subgenus Ruticosa. 相似文献
996.
【目的】本研究旨在阐明家蚕微孢子虫Nosema bombycis感染不同时间对家蚕Bombyx mori幼虫不同组织中家蚕海龟蛋白(Bombyx Turtle, Bmtutl)基因表达水平的影响,为揭示家蚕微孢子虫的侵染机制奠定基础。【方法】利用生物信息学方法对家蚕海龟蛋白3种亚型Bmtutl-464, Bmtutl-519和Bmtutl-810的序列结构特征进行了分析;利用qPCR检测家蚕微孢子虫感染后12, 24, 48, 72, 96和120 h,家蚕幼虫中肠、血淋巴与脂肪体组织中Bmtutl-464, Bmtutl-519和Bmtutl-810基因表达水平的变化情况。【结果】家蚕海龟蛋白3种亚型的二级结构均主要由无规则卷曲、α螺旋、β转角和延伸链组成,其中无规则卷曲所占比例最高。但是PredictProtein分析发现,Bmtutl-464, Bmtutl-519和Bmtutl-810之间的蛋白/多核苷酸结合位点存在较大差异。qPCR结果表明,感染家蚕微孢子虫后,家蚕幼虫中肠、血淋巴与脂肪体组织中Bmtutl-464, Bmtutl-519和Bmtutl-810基因的整体表达处于被抑制状态,尤其在脂肪体中最为明显:Bmtutl-519和Bmtutl-810基因的表达在家蚕微孢子虫感染家蚕后的72 h开始受到显著抑制,特别是Bmtutl-519基因,其相对表达水平均不到对照的5.0%。【结论】家蚕海龟蛋白这3种亚型的序列结构特征存在较大差异,家蚕微孢子虫感染在一定程度抑制了家蚕幼虫中肠、血淋巴与脂肪体组织中Bmtutl-464, Bmtutl-519和Bmtutl-810基因尤其是Bmtutl-519的表达。结果说明,与其他两种家蚕海龟蛋白亚型相比,Bmtutl-519蛋白可能在家蚕微孢子虫侵染宿主的过程中起主要作用。 相似文献
997.
Parkinson's disease (PD) is a neurodegenerative disorder involving progressive deterioration of dopaminergic neurons. Although few genetic markers for familial PD are known, the etiology of sporadic PD remains poorly understood. Microarray data was analysed for induced pluripotent stem cells (iPSCs) derived from PD patients and mature neuronal cells (mDA) differentiated from these iPSCs. Combining expression and semantic similarity, a highly-correlated PD interactome was constructed that included interactions of established Parkinson's disease marker genes. A novel three-way comparative approach was employed, delineating topologically and functionally important genes. These genes showed involvement in pathways like Parkin-ubiquitin proteosomal system (UPS), immune associated biological processes and apoptosis. Of interest are three genes, eEF1A1, CASK, and PSMD6 that are linked to PARK2 activity in the cell and thereby form attractive candidate genes for understanding PD. Network biology approach delineated in this study can be applied to other neurodegenerative disorders for identification of important genetic regulators. 相似文献
998.
A new genus and species, Espanoderus barbarae gen. et sp. nov., belonging to the family Tanyderidae (Diptera, Nematocera), is described from Lower Cretaceous amber of Spain (Álava amber). The new genus is the smallest member of Tanyderinae and the first member of the family from the Álava amber. The position of the new genus in a phylogenetic tree of Tanyderidae is presented.
http://zoobank.org/urn:lsid:zoobank.org:pub:EC3284BA-C07F-48AC-8AF5-4F9D2EF4EA6C 相似文献
999.
In this work, we study the effect of different variables affecting elution profile distortion on the enantiomeric resolution eventually achievable when working with on‐line coupled liquid chromatography to gas chromatography (LC‐GC). Specifically, the proposed configuration combines achiral reversed‐phase liquid chromatography (RPLC) and chiral gas chromatography (enantio‐GC), with heptakis‐(2,3,6‐tri‐O‐methyl)‐β‐cyclodextrin as enantioselective stationary phase to analyse target fractions transferred (from LC to GC) via the through oven transfer adsorption desorption (TOTAD) interface. The high degree of orthogonality resulting from the combination of two chromatographic columns having very different separation mechanisms (and also requiring mobile phases in distinct physical states), as well as integration of the sample preparation step in the first dimension of the system, significantly contributed to exploit the performance of the proposed two‐dimensional approach. Occasional adverse effects, which may result in severe peak distortions during LC‐GC analysis and could be explained by flow instabilities due to viscous fingering, are circumvented by using the outstanding capacity of the TOTAD interface for achieving effective elimination of the eluent arriving from the LC preseparation. 相似文献
1000.
Xin Chen Jiahong Yu Changhu Xue Yuming Wang 《Bioscience, biotechnology, and biochemistry》2019,83(7):1227-1238
Here we have explored the effect of neoagarotetraose (NAT) on liver injury caused by intense exercise. Our results showed that NAT treatment obviously decreased liver weight (p < 0.01), improved the liver morphological structure, decreased ALT level (p < 0.05) and endotoxin (LPS) (p < 0.01). In addition, NAT could regulate bile acid profiles in feces and serum of mice, which indicated the potential of liver function, suggesting that NAT was effective to relieve intense exercise-induced liver injury. NAT could regulate the expression of colon genes. NAT tended to alter the microbial composition of mice under intense exercise. We uncovered the network interactions between liver traits and microbial communities in NAT treatment mice. Interestingly, our data indicated that intense exercise-induced liver injury may be related to Clostridiales. In summary, these results demonstrated that NAT relieved liver injury induced by intense exercise may be related to gut microbiota. 相似文献