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841.
842.
原花青素(proanthocyanidins,PC)是目前国际上公认的清除人体内自由基最有效的天然抗氧化剂,广泛分布于多种天然植物中。阐述了葡萄废弃物中原花青素的功能,分析了其应用开发现状。结合常用的提取方法,并综合国内外关于原花青素的研究进展,对葡萄籽中原花青素提取的工艺参数进行优化,从而得出葡萄籽中原花青素最优提取方案。以期为葡萄籽的全面利用和原花青素的工业化生产提供科学依据,使原花青素拥有更广泛的应用。 相似文献
843.
在本实验室前期利用白色杜洛克×二花脸F2资源家系开展脐疝易感位点全基因组扫描定位的基础上,文章在7号染色体上的SWR1928和10号染色体上的SW830易感标记区域,结合脐疝发病机制在多群体中进行脐疝位置功能候选基因的筛选和易感位点的精细定位。在两个显著关联的微卫星位点区域搜寻到12个位置功能候选基因,采用比较测序法,选取12个候选基因内共计40个SNP位点在白色杜洛克×二花脸资源家系F2/F3脐疝群体中进行基因分型,利用Plink v1.07软件对基因型数据进行质量控制和传递不平衡(Transmission disequilibrium test,TDT)分析。结果表明,IL16(Interleukin 16)基因中的g.708C>T位点和CDC73(Cell division cycle 73)基因中的g.10664G>A位点与脐疝的关联性达到显著水平(P<0.05)。对这两个位点在西方商业猪种脐疝患病家系中进行基因分型和TDT验证分析,发现CDC73基因中的g.10664G>A位点仍与猪脐疝呈显著关联(P<0.05)。同时对CDC73基因中与资源家系脐疝呈弱相关的两个SNP位点g.10546A>G和g.10811A>G在西方商业猪种中进行TDT验证分析,发现这两个SNP位点与商业猪种脐疝发生的关联性达到极显著水平(P<0.01)。根据文章的分析结果,结合脐疝发生的生理机制及CDC73基因的生物学功能,推测CDC73基因可能为猪脐疝发生的易感基因。 相似文献
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847.
Qianming Dou Xue Du Yanfeng Cong Le Wang Chen Zhao Dan Song Hui Liu Tangbin Huo 《Ecology and evolution》2022,12(2)
The structural characteristics of the macroinvertebrate community can effectively reflect the health status of lake ecosystems and the quality of the lake ecological environment. It is therefore important to identify the limiting factors of macroinvertebrate community structure for the maintenance of lake ecosystem health. In this study, the community composition of macroinvertebrate assemblages and their relationships with environmental variables were investigated in 13 small lakes within Lianhuan Lake in northern China. A self‐organizing map and K‐means clustering analysis grouped the macroinvertebrate communities into five groups, and the indicator species reflected the environmental characteristics of each group. Principal component analysis indicated that the classification of the macroinvertebrate communities was affected by environmental variables. The Kruskal–Wallis test results showed that environmental variables (pH, total phosphorus, nitrate, water temperature, dissolved oxygen, conductivity, permanganate index, and ammonium) had a significant effect on the classification of the macroinvertebrate communities. Redundancy analysis showed that mollusks were significantly negatively correlated with pH and chlorophyll a, while annelids and aquatic insects were significantly positively correlated with chlorophyll a and dissolved oxygen. Spearman correlation analysis showed that the species richness and Shannon''s diversity of macroinvertebrates were significantly negatively correlated with total phosphorus, while the biomass of macroinvertebrates was significantly negatively correlated with pH. High alkalinity and lake eutrophication have a serious impact on the macroinvertebrate community. Human disturbances, such as industrial and agricultural runoff, negatively impact the ecological environment and affect macroinvertebrate community structure. Thus, macroinvertebrate community structure should be improved by enhancing the ecological environment and controlling environmental pollution at a watershed scale. 相似文献
848.
Xue Zhou Xiaoli Xie Ting Liu Shengxiong Chen Yijun Wang Jiuna Zhang Shuling Wang Yongjuan Wang Shiying Dou Ran Qi Ning Kang Dongxuan Zhang Xiaoxu Jin Ruolin Cui Huiqing Jiang 《Translational oncology》2022,15(1)
Cancer/testis antigens (CTAs) are often aberrantly expressed in cancer stem cells (CSCs) which are responsible for tumor metastasis. Rec8 meiotic recombination protein (REC8), a member of CTAs, shares distinct roles in various cancers, while its contribution to CSCs and colorectal cancer (CRC) remains unclear. We found that overexpression of REC8 facilitated the migration and invasion of CRC cells (DLD-1 and SW480 cells) in vitro and promoted the liver metastasis of CRC in vivo. Moreover, REC8 is highly expressed in CRC stem-like cells and is required for the maintenance of CSC stemness. Mechanistic studies suggested that REC8 mediated through the activation of Bruton tyrosine kinase (BTK). Inhibition of BTK by ibrutinib not only suppressed the migration and invasion-promoting ability, but also declined the increased expression of p-BTK, p-Akt, β-catenin, and CSC markers upon REC8 overexpression. Importantly, high expression of REC8 in cancerous tissues was related to advanced clinical stage and lymph node metastasis of 62 CRC patients, and REC8 was enriched in the cancerous cells positive for CSC markers. Collectively, our results indicate that REC8 promotes CRC metastasis by increasing cell stemness through BTK/Akt/β-catenin pathway. 相似文献
849.
Chin Hui-Chen Chang Mei-Chen Ling Ping-Ping Ting Chih-Tsun Dou Fang-Ping 《植物分类学报:英文版》1985,23(1):11-18
The chromosome numbers of 5 tuberous sections of Chinese Dioscorea, including 23 species and varieties, are reported in the present paper as a continuation of the previous reports. They are all polyploids with the basic number x=10. On the basis of analysis of chromosome numbers of whole genus, the rhizomatous diploid species of Sect. Stenophora Uline are presumed to be primitive taxa, while the polyploids of chromosome numbers 40-142 are considered derived groups as a result of hybridization between their ancestral diploids followed by chromosome doubling. Sect. Lasiophyton Pr. et Burk., Sect. Opsophyton UIine, Sect. Shannicorea Pr. et Burk., Sect. Combilium Pr. et Burk. and Sect. EnantiophylIum Uline may be the advanced groups. The chromosomal evolution and geographical distribution suggest that the primitivediploid might have originated in Hengduan Mountains of Asia, an old highland. 相似文献
850.
Apart from roots, rhizome, stem, the adaxial surfaces of the leaf sheaths and palea in the body of the plant of Spartina anglica, the salt glands are found in all other aerial parts, especially, they are abundant in lamina. The gland is composed of two differential cells, a big basal cell and a small, dome- shaped cap cell which is located on the neck-like protrusion of the basal cell. Both of the cap cell and the basal cell have dense cytoplasm, large nucleus, numerous mitoehondria and a few other organelles. The basal cell has wall protuberances, and infoldings of the partitioning membrane system which extend throughout the basal cell, and separate the basal cell cytoplasm. A dominant feature of the cap cell is the distinct compach, nueleolus and its chromatin distributed throughout the karyoplasm. In shoulder and bottom of the basal cell there is no cuticular layer separating them from the epidermal cell and mesophyll cells, but in the walls connceting the basal cell with the epidermal cells and cap cell there are pronounced plasmodesmata. It is possible that devolopment of the gland in Spartina anglica is the same as in S. townsendii, and that pathway of secretion is similar to both of S. foliosa and S. townsendii. 相似文献