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91.
生物活性物的生物制造是指利用包括细胞、微生物和酶在内的生物系统生产具有生物活性的天然或合成分子的过程。这些分子可用于制药、化妆品、农业和食品工业等领域,对提高生命质量、延长生命长度具有重要意义。在合成生物学和自动化等技术的推动下,生物制造领域迅速发展,为创造新产品和替代传统产品提供了绿色可持续的生产模式,为生物经济的增长、创新作出了重要贡献。本文结合生物活性物研发及生产情况,简要梳理并分析了国内外生物活性物的现有市场和未来发展。生物制造作为一种绿色、可持续的生产方式,将在生物经济发展中持续发挥重要作用。  相似文献   
92.
苄基异喹啉化合物是一类钙调素拮抗剂.对新合成的双苄基异喹啉化合物 D20对钙调素依赖的磷酸二酯酶的抑制作用进行了研究,IC50=5μmol/L,表明其拮抗作用大于三氟啦嗪,是强的拮抗剂.荧光分析表明,钙调素与化合物 D20的结合常数为2.64(μmol/L)-1,一个化合物 D20分子与两个钙调素分子结合,并显示了结合方向性及空间位阻影响.  相似文献   
93.
甘蓝型油菜子叶和下胚轴再生植株无性系建立   总被引:4,自引:1,他引:3  
以甘蓝型油菜(Brassica napus L.)豫油2号和6257的子叶和下胚轴为材料,在不同激素配比的MS培养基上诱导出了愈伤组织。将经过继代的部分愈伤转入分化培养基,分化结果表明:除基因型、外植体和分化培养基的激素配比对分化率有影响外,诱导愈伤培养基的激素配比对分化率也至关重要。豫油2号的子叶和下胚轴在最适诱导培养基(ZT 1+NAA0.5+2,4-D 0.2 mg/L)和最适分化培养基(ZT4+IAA 0.2 mg/L)组合中的愈伤分化率分别为12.5%和75%;6257的子叶和下胚轴在其最适诱导培养基(KT 2+NAA1+2,4-D 0.2 mg/L)和最适分化培养基(6-BA 4+IAA 0.02 mg/L)组合中的愈伤分化率分别为50%和37.5%。将其最适诱导培养基中的愈伤组织继代达8个月以上,建立了不同继代愈伤的再生植株无性系。  相似文献   
94.
Long non-coding RNAs (lncRNA) have an extensive role in the progression and chemoresistance of gastric cancer (GC). Deeply study the regulatory role of lncRNAs could provide potential therapeutic targets. The aim of this study is to explore the regulatory role of HOTAIR in the progression and oxaliplatin resistance of GC. The expression of HOTAIR in GC and cell lines were detected by using qRT-PCR. Cell proliferation and apoptosis were analysed by CCK-8, EdU incorporation and flow cytometry. Luciferase reporter assay was used to identify the interaction between HOTAIR and ABCG2 (ATP-binding cassette (ABC) superfamily G member 2, ABCG2) via miR-195-5p. The regulatory functions were verified by using molecular biology experiments. HOTAIR was significantly overexpressed in GC and associated with poor prognosis. Knock-down of HOTAIR inhibited the GC cells proliferation and oxaliplatin resistance, while overexpression of HOTAIR showed opposite functions. Further studies found that HOTAIR acted as a competing endogenous RNA (ceRNA) to absorb miR-195-5p and elevated the expression of ABCG2, which leads to resistance of GC cells to oxaliplatin. Taken together, our findings demonstrated that HOTAIR regulates ABCG2 induced resistance of GC to oxaliplatin through miR-195-5p signalling and illustrate the great potential of developing new therapeutic targets for GC patients.  相似文献   
95.
本文选用10个DMD基因内部和桥探针,对山东省9个地区的21个DMD/BMD家系的173名成员进行RFLP分析,其中可疑携带者55人,多数家系应用1-3个探针,有基因重组家庭选用4-5个探针,便可完成多态分析,RFLP分析可以确定85.45%的可疑携带者(≥95%可信限),即13人确定为携带者,30人排除携带者,另有4人风险大幅提高,通过这些探针的群体多态检测和不同家庭结构和类型的应用分析,我们提出了在中国人群中DMD/SMD基因诊断的基本程序。  相似文献   
96.
97.
Bletilla striata (Thunb.) Reichb.f. is a perennial herb with abundant active ingredients. Previous research mainly focused on its tubers, however, the study on flowers, especially the variation of active ingredient contents at different flowering stages, was rarely seen. This study analyzed the total phenols, flavonoids, polysaccharides, anthocyanins, and cyanidin-3-O-glucoside content of B. striata flowers which were in cultivated in Herb Garden of Zhejiang A&F University and collected in May, 2019, in order to investigate the changes in active ingredients and antioxidant capacity among different flowering stages (bud, initial, and full bloom). Changes in radical scavenging capability of DPPH (1,1-Diphenyl-2-picrylhydrazyl radical), ABTS (2,2′-azinobis(3-ethylbenzthiazoline-6-sulphonate)), and hydroxy were analyzed. Significant differences in active ingredient content of flowers were detected among different flowering stages. The total phenolic content increased continuously during the entire flowering stage. The contents of total flavonoid, total polysaccharide, and cyanidin-3-O-glucoside reached peaks at the initial blooming stage and then fell as the flowering process continued. The antioxidant activity in initial stage was the highest than in any other flowering stages. Therefore, we conclude that the initial blooming stage is the best harvesting stage of B. striata flowers. This study provides a robust basis for the harvest and utilization of B. striata flowers in food, medical, and cosmetic industries.  相似文献   
98.
This work firstly reported a new polycaprolactone based material functionalized with guanidinium ionic liquid (PCL-GIL) as the stationary phase with high resolution performance for capillary gas chromatography (GC). It is composed of polycaprolactone (PCL) and guanidinium ionic liquid (GIL) with amphiphilic conformation. The PCL-GIL capillary column coated by static method exhibited high column efficiency of 3942 plates/m and moderate polarity. As a result, the PCL-GIL column exhibited high-resolution capability. For a mixture of 27 analytes with a wide ranging polarity and outperformed the PCL-2OH and HP-35 columns, showing its advantageous separation capability for analytes of diverse types. Moreover, the PCL-GIL column showed high resolving capability for various positional isomers and cis-/trans-isomers, including alkylbenzenes, chlorobenzenes, naphthalenes, bromonitrobenzenes, chloronitrobenzenes, benzaldehydes, phenols, alcohols, respectively. In a word, PCL derivatized by GIL units as a new type of stationary phase has a promising future in GC separations.  相似文献   
99.
100.
The power conversion efficiencies (PCEs) of all-polymer solar cells (all-PSCs) have already exceeded 17%. However, the limited absorption range of an all-polymer system results in significantly reduced short-circuit current density (Jsc), which eventually influences the PCE improvement. To broaden the light absorption of polymer acceptors, herein, benzotriazole is introduced in the core unit of small molecule acceptors and thus two narrow-bandgap polymer acceptors named PTz-BO and PTz-C11 featuring the same molecular backbone and different side-chain length are synthesized. Compared with PTz-C11, the PTz-BO based-all PSCs deliver a slightly reduced Jsc, a large open-circuit voltage (Voc) and a low voltage loss below 0.50 V. Moreover, ternary all-PSCs are constructed by introducing PTz-C11 as a guest component. Benefiting from the reduced recombination, improved exciton generation and dissociation, and balanced charge transport, a high efficiency of 16.58% is obtained for the ternary all-PSCs, with a high Jsc over 25 mA cm−2 without sacrificing the Voc. Such result represents the highest efficiency reported for benzotriazole-based all-PSCs in the literature thus far. This work demonstrates the great potential of benzotriazole for the synthesis of efficient narrow-bandgap polymer acceptors.  相似文献   
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