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161.
Zhang Hongling Ran Chao Teame Tsegay Ding Qianwen Hoseinifar Seyed Hossein Xie Mingxu Zhang Zhen Yang Yalin Olsen Rolf Erik Gatlin Delbert M. Ringø Einar Duan Ming Zhou Zhigang 《Reviews in Fish Biology and Fisheries》2020,30(4):569-586
Reviews in Fish Biology and Fisheries - The intestinal mucosal barrier plays a critical role in the maintenance of host health. In farmed teleost fish, the intestinal epithelium is challenged by a... 相似文献
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Xiu‐li Liu Lan Wang Xiao‐wen Wang Yan Yan Xiao‐li Yang Meng‐yang Xie Zhi Hu Xing Shen Hao Ai Hong‐hui Lin Guo‐hua Xu Jian Yang Shu‐bin Sun 《The Plant journal : for cell and molecular biology》2020,102(1):53-67
Phosphorus (P) is an essential macronutrient required for plant development and production. The mechanisms regulating phosphate (Pi) uptake are well established, but the function of chloroplast Pi homeostasis is poorly understood in Oryza sativa (rice). PHT2;1 is one of the transporters/translocators mediating Pi import into chloroplasts. In this study, to gain insight into the role of OsPHT2;1‐mediated stroma Pi, we analyzed OsPHT2;1 function in Pi utilization and photoprotection. Our results showed that OsPHT2;1 was induced by Pi starvation and light exposure. Cell‐based assays showed that OsPHT2;1 localized to the chloroplast envelope and functioned as a low‐affinity Pi transporter. The ospht2;1 had reduced Pi accumulation, plant growth and photosynthetic rates. Metabolite profiling revealed that 52.6% of the decreased metabolites in ospht2;1 plants were flavonoids, which was further confirmed by 40% lower content of total flavonoids compared with the wild type. As a consequence, ospht2;1 plants were more sensitive to UV‐B irradiation. Moreover, the content of phenylalanine, the precursor of flavonoids, was also reduced, and was largely associated with the repressed expression of ADT1/MTR1. Furthermore, the ospht2;1 plants showed decreased grain yields at relatively high levels of UV‐B irradiance. In summary, OsPHT2;1 functions as a chloroplast‐localized low‐affinity Pi transporter that mediates UV tolerance and rice yields at different latitudes. 相似文献
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鲎是古老的海洋节肢动物。中华鲎(Tachypleus tridentatus)是世界现存4种鲎中体型最大的一种, 是河口生态系统的标志物种, 同时其血液被用于生产医用检验试剂――鲎试剂。中华鲎的自然地理分布范围相当狭窄, 仅局限于日本濑户内海向南延伸至印度尼西亚爪哇岛北岸以北的太平洋西岸海域, 其中在中国东岸和日本南部海域的历史产量较高。自20世纪50年代以来中华鲎种群数量出现了显著减少, 2019年中华鲎在IUCN红色名录中的濒危等级正式更新为濒危(EN), 明确了中华鲎资源呈现全球性衰退的状态, 究其原因可归纳为鲎生境破坏和过度捕捞两个方面。在开展鲎资源保护的实践工作中, 作者深刻反思当前鲎资源保护在海洋保护区划定、增殖放流及科普和野生动物保护法宣传中存在的问题并提出相应建议, 包括加快完善种群基线数据, 制定标准化种群和生境基线监测指南, 构建科学放流体系等, 以期推进全球范围内的中华鲎资源保护与科学管理。 相似文献
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Jun Wang Jiancheng Hu Tao Tang Jani Heino Xiaoming Jiang Zhengfei Li Zhicai Xie 《Ecology and evolution》2020,10(2):692-704
Identifying seasonal shifts in community assembly for multiple biological groups is important to help enhance our understanding of their ecological dynamics. However, such knowledge on lotic assemblages is still limited. In this study, we used biological traits and functional diversity indices in association with null model analyses to detect seasonal shifts in the community assembly mechanisms of lotic macroinvertebrates and diatoms in an unregulated subtropical river in China. We found that functional composition and functional diversity (FRic, FEve, FDis, MNN, and SDNN) showed seasonal variation for macroinvertebrate and diatom assemblages. Null models suggested that environmental filtering, competitive exclusion, and neutral process were all important community assembly mechanisms for both biological groups. However, environmental filtering had a stronger effect on spring macroinvertebrate assemblages than autumn assemblages, but the effect on diatom assemblages was the same in both seasons. Moreover, macroinvertebrate and diatom assemblages were shaped by different environmental factors. Macroinvertebrates were filtered mainly by substrate types, velocity, and CODMn, while diatoms were mainly shaped by altitude, substrate types, and water quality. Therefore, our study showed (a) that different biological assemblages in a river system presented similarities and differences in community assembly mechanisms, (b) that multiple processes play important roles in maintaining benthic community structure, and (c) that these patterns and underlying mechanisms are seasonally variable. Thus, we highlight the importance of exploring the community assembly mechanisms of multiple biological groups, especially in different seasons, as this is crucial to improve the understanding of river community changes and their responses to environmental degradation. 相似文献
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Evaluating how decomposition rates and litter nutrient release of different litter types respond to changes in water conditions is crucial for understanding global carbon and nutrient cycling. However, it is unclear how decreasing water affects litter mixture interactions for the maize–poplar system in arid regions. Here, the responses of the litter decomposition process and litter mixture interactions in the agroforestry system to changes in water conditions (control, light drought, and moderate drought) were tested. Moderate drought significantly decreased the decomposition rate for poplar leaf and mixed litters, and decomposition rate was significantly reduced for maize straw litter in light and moderate drought stress. The mass loss rates of maize straw and mixed litters were significantly higher than that of the poplar leaf litter under drought conditions, but there was no significant difference among the three litter types in the control. There was no interaction between mass loss of the mixed litter in the control and light drought conditions, and the litter mixture interaction showed nonadditive synergistic interactions under moderate drought. In terms of nutrient release, there was also no interaction between litter mixture with nitrogen and carbon, but there was antagonistic interaction with potassium release under the light drought condition. Our results demonstrate that drought conditions can lead to decreasing decomposition rate and strong changes in the litter mixture interactions from additive effects to nonadditive synergistic effects in moderate drought. Moreover, light drought changed the mixture interaction from an additive effect to an antagonistic interaction for potassium release. 相似文献
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目的探讨国产西罗莫司与原研品对移植宿主外周血中免疫细胞的影响效果。方法体外实验:人膀胱癌T24细胞体外培养,分别加入国产西罗莫司和原研品,CKK-8法检测并比较细胞增殖活性受抑制的情况。体内实验:建立小鼠异位心脏移植模型,设立对照无手术组(对照组)、移植无治疗组(Tx组)、移植+国产西罗莫司组(Tx+YXK组)、移植+原研品组(Tx+RAPA组)。观察移植心脏搏动情况,受者脾脏的流式细胞学检测,以及脾脏及移植物中免疫细胞浸润的病理检查。流式细胞检测树突状细胞(DC),CD8+细胞和调节性T细胞(Treg),病理组织学检测及免疫组化染色比较两组免疫细胞浸润情况。两组间比较采用独立样本t检验,多组间比较采用单因素方差分析,两两比较采用LSD-t检验。结果体外实验结果显示,国产西罗莫司与原研品对T24细胞活力影响的差异无统计学意义(P>0.05)。体内实验结果显示,Tx组移植心脏于第7天停止搏动,Tx+YXK组和Tx+RAPA组在第10天心脏搏动仍有力、节律正常。(1)脾脏流式细胞检测显示,与对照组、Tx组比较,Tx+RAPA组、Tx+YXK组CD11c+I-A+CD86+DC细胞(15.88±4.73、22.90±3.86比4.51±1.57、5.40±2.54)、CD8+淋巴细胞数量(6.32±0.98、6.75±1.34比3.03±1.12、3.23±0.97)均降低,而Tx+RAPA组CD4+CD25+Foxp3+阳性细胞数量(15.06±3.42比7.87±1.95,10.88±2.08)升高(P均<0.05)。Tx+YXK组和Tx+RAPA组3种免疫细胞数量差异均无统计学意义(P>0.05)。(2)移植心脏病理免疫细胞组化染色灰度分析,Tx组、Tx+YXK组和Tx+RAPA组CD4,CD8,IDO和CD11b数量差异无统计学意义(P>0.05),与Tx组比较,Tx+RAPA组和Tx+YXK组CD11c(25143.52±3525.12比12936.30±766.94、14240.60±3124.67)、Foxp3阳性细胞浸润数量(500.78±238.33比46.05±68.16、49.22±25.82)降低(P均<0.05),Tx+YXK组和Tx+RAPA组比较差异无统计学意义(P>0.05)。(3)模型动物脾脏病理免疫细胞组化染色灰度分析,Tx组CD 4和CD8阳性细胞浸润数量较Tx+YXK组和Tx+RAPA组少,但差异无统计学意义(P>0.05),Tx+YXK组和Tx+RAPA组比较,各种细胞染色的IOD值差异均无统计学意义。结论使用国产西罗莫司与原研品两种药物后受者移植心脏和脾脏中的细胞浸润变化一致;在体外对细胞增殖、移植后抗排斥作用和体内免疫细胞的影响表现均一致。 相似文献
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