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11.
金线蛙各月份的食性分析表明,成蛙以捕食昆虫为主,首食种类是水生动物中的负子昃、螺、虾等,摄食种类变化主要与生境及生长发育相关。  相似文献   
12.
Chen  Chunli  Xie  Xiangyun  Li  Xue 《Glycoconjugate journal》2021,38(4):517-525

Four neutral polysaccharides (ESBP1-1, ESBP1-2, ESBP2-1 and ESBP3-1) were successfully purified from the water extracted crude polysaccharides of Erythronium sibiricum bulbs through the combination of DEAE Sepharose CL-6B and Sephadex G-100 chromatography; their average molecular weights were 1.3?×?104, 1.7?×?104, 9.4?×?105 and 4.1?×?105 Da, respectively. Monosaccharide component analysis indicated that ESBP1-1 and ESBP1-2 were mainly composed of glucose (Glc). ESBP2-1 was composed of Glc, galactose (Gal) and arabinose, with a molar ratio of 24.3:1.1:1, whereas ESBP3-1 comprised Glc and Gal at a molar ratio of 14.8:1. In-vitro study showed that all of the four polysaccharides were able to considerably promote the proliferation and neutral red phagocytosis of RAW 264.7 macrophage cell. They could also stimulate the production of the cell lines’ secretory molecules [nitric oxide, tumour necrosis factor-α (TNF-α) and interleukin-1β (IL-1β)] in a dose-dependent manner. However, ESBP1-2 was not included in IL-1β. Overall, these results suggested that polysaccharides from E. sibiricum bulbs can be developed as immunomodulatory ingredients for complementary medicines or functional foods. However, further animal or clinical studies are required.

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13.
Anthocyanins play important role in plant protection and were closely involved with the plant evolution. Anthocyanidin synthase (ANS) is a late key enzyme in the flavonoid pathway which can catalyze leucoanthocyanidins to anthocyanidins. By our study, we found a miniature inverted-repeat transposable element (MITE) inserting in the promoter of ANS gene of mulberry. We used strawberry to evaluate the activities of ANS promoters from Morus alba and Morus notabilis with the method of Agrobacterium-mediated transient expression. The expression patterns of different promoters were also analyzed in transgenic lines of Arabidopsis thaliana and in this study, GUS was used as reporter gene. The 564-bp MITE insertion was strongly required for the activities of ANS promoter and it may reprogram the expression profiles of ANS gene in mulberry. Our results suggested that the MITE insertion was probably involved in either domestication or natural selection.  相似文献   
14.
New perinatal care technologies have improved the survival rate of preterm neonates, but the prevalence of bronchopulmonary dysplasia (BPD), one of the most intractable problems in neonatal intensive care unit (NICU), remains unchanged. In present study, high-throughput sequencing (HTS) was performed to detect the expression profiles of long noncoding RNAs (lncRNAs), messenger RNAs (mRNAs), circular RNAs (circRNAs), and microRNAs (miRNAs) in hyperoxia-induced BPD mouse model. Significant differentially expressed RNAs were selected and clustered between the BPD group and the control group. The results revealed that expressions of 1778 lncRNAs, 1240 mRNAs, 97 circRNAs, and 201 miRNAs were significantly altered in the BPD group. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) were performed to predict the potential functions of differentially expressed RNAs. lncRNA-mRNA and circRNA-miRNA coexpression networks were constructed to detect their association with the pathogenesis of BPD. Our study provides a systematic perspective on the potential function of RNAs during BPD.  相似文献   
15.
硼营养与植物细胞壁关系的研究进展   总被引:5,自引:0,他引:5  
植物必需的7种微量元素中,植物缺硼最为普遍,因而引起人们的广泛关注。半个多世纪以来,学者们对硼的生理功能和硼肥应用进行了广泛的研究,为农业生产作出了重大贡献。但由于硼元素的特殊性,至今对硼在植物体内的存在形式和基本生理功能仍不十分清楚。不同植物的缺硼症状尽管各不相同,但一个显著的共同特征就是根尖和茎尖的伸长首先受到抑制。顶端生长依赖于细胞分裂和细胞伸长,由此可见,硼必然首先影响分生组织的细胞分裂和细胞伸长。硼对细胞分裂的影响已进行了大量的研究。Whittington〔1〕曾报道缺硼减少大豆有丝分…  相似文献   
16.
Proteins destined for degradation by the ubiquitin-proteasome system are labelled with a 76-amino acid peptide, ubiquitin, through a series of conjugation steps by the E1, E2 and E3 enzymes respectively. Ubiquitin carboxy-terminal hydrolase 37 (UCH37) belongs to the UCH proteases family that deubiquitinates ubiquitin-protein conjugates in the ubiquitin-proteasome system. However, it is few reports about the relationship between UCH37 and apoptosis. In order to clarify the role of UCH37 on apoptosis, the A549 cells were chosen for this study. We transfected UCH37 siRNA and pcDNA3.1-UCH37 plasmid into A549 cells, respectively. Using MTT assay, Western blot, Hoechst 33342 staining assay and flow cytometry, we found that silencing of UCH37 in A549 cells induced apoptosis. The ratio of Bax/Bcl-2 was higher in silencing of UCH37 than that in control group after silencing of UCH37 in A549 cells. Meanwhile, experiments with the A549 cell line disclose that silencing of UCH37 could induce efficiently A549 cell apoptosis through activation of caspase-9 and caspase-3. On the other hand, over-expression of UCH37 led to the opposite effect. Hence, UCH37 might play an important role in apoptotic through altering Bax/Bcl-2 ratio and enzymatic activities of caspase-9 and caspase-3.  相似文献   
17.
朱相云 《生物多样性》2015,23(2):247-251
<正>豆科(Leguminosae/Fabaceae)是被子植物中继菊科和兰科之后的第三大科,全世界约有36族727属19,325种(Lewis et al.,2005)。中国有豆科植物33族180属1,670种(Zhu et al.,2007),也有学者认为有29族167属1,673种(Xu et al.,2010)。最新研究表明(朱相云等,2015,待发表),中国有豆科植物约33族183属1,859种(含归化种、栽培种)。豆科植物与人们的生活密切相关,我们日常食用的绿豆(Vigna radiata(L.)R.Wilczek)、大豆(Glycine max(L.)Merr.)和豌豆(Pisum sativum L.),药用的黄芪(Astragalus  相似文献   
18.
Anti-PspA antibodies are less efficient at protecting mice against certain pneumococcal strains. Immunization with PspA from EF5668 provided better protection against WU2 (a different capsular serotype and PspA family) than against EF5668. To understand the role of the pneumococcal genetic background in anti-PspA-mediated protection, we constructed a mutant of WU2 expressing pspA from EF5668. Both passive and active immunization demonstrated that the genetic background impacted the protection mediated by anti-PspA antibodies. We localized the protection-eliciting region to the first 122 amino acid residues of the N-terminus of the alpha-helical domain of PspA/EF5668.  相似文献   
19.
Six newly derived hybrid mouse embryonic stem (ES) cell lines and two inbred ES cell lines were tested for their ability to produce completely ES cell-derived mice by aggregation of ES cells with tetraploid embryos. Forty-five ES cell-tetraploid pups were generated from six hybrid ES cell lines and no pups from two inbred ES cell lines. These pups were found to have increased embryonic and placental weights than control mice. Twenty-two pups survived to adulthood and produced normal offsprings, and the other 23 pups died of several reasons including respiratory distress, abdomen ulcer-like symptoms, and foster failure. The 22 adult ES cell-tetraploid mice were completely ES cell-derived as judged by coat color and germline transmission, only two of them was found to have tetraploid component in liver, blood, and lung as analyzed by microsatellite loci. Our data suggested that genetic heterozygosity is a crucial factor for postnatal survival of ES cell-tetraploid mice, and tetraploid embryo aggregation using hybrid ES cells is a simple and efficient procedure for immediate generation of targeted mouse mutants from genetically modified ES cell clones, in contrast to the standard protocol, which involves the production of chimeras and several breeding steps.  相似文献   
20.
影响牛胚胎干细胞分离克隆因素的研究   总被引:24,自引:0,他引:24  
采用与同源胎儿成纤维细胞共同培养及传统饲养层培养方式,以高糖DMEM,添加0.1mM2-巯基乙醇,犊牛血清,细胞因子为培养基,以4-13周龄屠宰牛胎儿为实验材料,探讨影响牛原始生殖细胞分离克隆胚胎干细胞的相关因素,结果发现:当犊牛血清为15%时效果最好;细胞因子添加与否对胚胎干细胞的分离及同源牛胎儿成纤维细胞的贴壁与生长影响并不显著,而在传代过程中中有一定影响;以0.2%胰酶 0.04?TA为细胞消化液效果最佳;以同源胎儿成纤维细胞共培养的方式分离克隆牛胚胎干细胞,本研究观察到效果最好。  相似文献   
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