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91.
Yu  Jinlei  Xia  Manli  Zhao  Yanyan  He  Hu  Guan  Baohua  Chen  Feizhou  Liu  Zhengwen  Jeppesen  Erik 《Hydrobiologia》2021,848(18):4335-4346

Small fish are highly associated with submerged macrophytes but may potentially hamper their growth due to nutrient excretion that stimulate growth of phytoplankton and periphyton growth. We conducted a mesocosm experiment to elucidate the effects of the small omnivore Chinese bitterling Acheilognathus macropterus on the growth of phytoplankton, periphyton and the submerged macrophyte Vallisneria denseserrulata. The treatments were fishless as well as low (LF) and high (HF) fish density. We found that the concentrations of nutrients and the phytoplankton biomass increased substantially in both fish treatments, leading to a significantly higher light attenuation compared with the control. Moreover, bitterling substantially enhanced the biomass of periphyton on plant leaves. Consequently, the relative growth rate (RGR) of V. denseserrulata was significantly suppressed in HF, while RGR in the LF treatment did not differ significantly from the controls. However, the bitterling also stimulated the ramet production of V. denseserrulata, significantly. Our results indicate that Chinese bitterling reduce the RGR of V. denseserrulata under high fish density condition. Therefore, the density of Chinese bitterling should be kept low in order to reduce the negative effects of the fish on the RGR of submerged macrophytes (e.g. V. denseserrulata), when restoring lakes by plant transplantation.

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92.
高血压(hypertension,high blood pressure)是动脉血压持续偏高的慢性疾病,是人类社会最为常见的慢性医学问题.80%以上的高血压患者了解他们自身的血压状况,其中70%以上的患者服用治疗高血压药物.然而,这些认识到自身高血压状况的人中,只有48%的患者的高血压得到了充分的控制.本文系统地阐述了高血压的类型、诊断标准及治疗或控制策略,以期提高公众对高血压的认知,有利于患者对高血压的控制和管理.  相似文献   
93.
ERF(ethylene-responsive factor)蛋白是植物中一大类转录因子家族,在植物的生长发育及逆境胁迫中发挥着重要作用.为研究丹参中新的转录因子SmERF1的功能,本研究对其编码序列、表达模式进行分析,并在丹参中进行过表达,检测过表达后转基因植株耐盐性、次生代谢物和激素的变化.研究结果表明,SmERF1含有一个AP2结构域,是典型的ERF转录因子.SmERF1受到MeJA和酵母诱导子(YE)的诱导表达.在盐胁迫下,过表达SmERF1的丹参株系中脯氨酸含量、SOD和POD活性较野生型丹参植株高,MDA含量降低,说明转基因株系的抗盐特性增强.而且过表达SmERF1的丹参株系中ABA含量升高,GA含量降低;过表达SmERF1对丹参酮、丹酚酸等代谢物的合成调控效果不强.综合以上结果,表明SmERF1可能通过调节ABA的合成,提高了丹参耐盐性.  相似文献   
94.
Chu  Qing  Xu  Tianjun  Zheng  Weiwei  Chang  Renjie  Zhang  Lei 《中国科学:生命科学英文版》2021,64(7):1131-1148
Viral infection induces the initiation of antiviral effectors and cytokines which are critical mediators of innate antiviral responses.The critical molecular determinants are responsible for triggering an appropriate immune response. Long noncoding RNAs(lncRNAs) have emerged as new gene modulators involved in various biological processes, while how lncRNAs operate in lower vertebrates are still unknown. Here, we discover a long noncoding RNA, termed antiviral-associated long noncoding RNA(AANCR), as a novel regulator for innate antiviral responses in teleost fish. The results indicate that fish MITA plays an essential role in host antiviral responses and inhibition of Siniperca chuatsi rhabdovirus(SCRV) production. miR-210 reduces MITA expression and suppress MITA-mediated antiviral responses, which may help viruses evade host antiviral responses. Further,AANCR functions as a competing endogenous RNA(ceRNA) for miR-210 to control protein abundance of MITA, thereby inhibiting SCRV replication and promoting antiviral responses. Our data not only shed new light on understanding the function role of lncRNA in biological processes in teleost fish, but confirmed the hypothesis that ceRNA networks exist widely in vertebrates.  相似文献   
95.
利用固体淀粉筛选培养基,从安阳市郊区面粉厂附近的土壤里分离筛选出1株产淀粉酶的菌株,编号为MF-3-2.经过菌株形态、革兰氏染色、16S rDNA鉴定及系统进化树分析,初步确定其为枯草芽孢杆菌(Bacillus subtilis).摇瓶培养后对其酶学性质研究发现,该菌株淀粉酶的最适温度为65℃,最适pH值为6.0,在pH值4.8~6.0范围内仍能残余70%以上的酶活力.该菌株的最适生长温度为40℃,最适生长pH值为6.5.产酶条件优化结果表明:最适碳源为马铃薯淀粉,最适氮源为豆粕粉,最适碳氮比为1∶15,发酵温度30℃,发酵pH值6.0,装液量10%,种龄10h,接种量5%,转速200 r/min,48 h达到产酶高峰.通过发酵产酶条件优化,其淀粉酶活性达到86.8 U/mL,是优化前的35倍.另外,在酸性条件下还具有较好的活性.因此,该菌株的淀粉酶具有潜在的工业应用前景.  相似文献   
96.
Dear Editor, A series of studies had focused on the ecological stability of human microbiome (Lozupone et al.,2012;Faith et al.,2013;Moya and Ferrer,2016).Despite the continuous perturbation and the highly personalized composition within the human microbiome (Human Microbiome Project,2012),healthy adults stably maintain their microbial communities in terms of space and time (Faith et al.,2013;Moya and Ferrer,2016;Oh et al.,2016).This stability is proved to be critical for the well-being of human body (Lozupone et al.,2012).On the contrary,major shifts in microbial community composition are often related to diseases (Lynch and Pedersen,2016).  相似文献   
97.

As the most important construction features of ancient Chinese cities, the city walls nowadays have lost their function of enemy defense and turned to affect the urban structure and development. To clarify the impact of ancient city walls on modern urban development, this work was conducted to measure the differences of landscape types and levels between the inner and outer walls of three typical ancient Chinese cities with the help of geoinformatics materials and landscape ecology indices. The results of this research proved that city walls have great impact on landscape pattern. Specifically, the aggregation, fragmentation, diversity and evenness of landscape were strongly affected by well-preserved ancient city walls. By sorting out and consulting historical documents and China's “City Walls Protection Regulations”, we also found that city walls help the old city to retain its original style and design characteristics. The findings of this quantitative-analysis-based historical study can provide a theoretical basis for the protection of historical heritage and landscape design.

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98.
99.
Ma  Bohan  Liu  Zhanzhu  Yan  Wei  Wang  Lixue  He  Haobo  Zhang  Aijing  Li  Zeyuan  Zhao  Qiuzhu  Liu  Mingming  Guan  Shuyan  Liu  Siyan  Qu  Jing  Yao  Dan  Zhang  Jun 《Functional & integrative genomics》2021,21(3):435-450
Functional & Integrative Genomics - Soybean oil is composed of fatty acids and glycerol. The content and composition of fatty acids partly determine the quality of soybean seeds. Circular RNAs...  相似文献   
100.
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