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281.
Zhang Qi Li Yanan Yin Chunping Yu Jiaxu Zhao Juan Yan Lirong Wang Qiujun 《Neurochemical research》2022,47(6):1751-1764
Neurochemical Research - Postoperative cognitive dysfunction (POCD) remains one of the most common complications following anesthesia and surgery (AS) in the elderly population. Calcium-mediated... 相似文献
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Spawning activity of the four major Chinese carps in the middle mainstream of the Yangtze River,during the Three Gorges Reservoir operation period,China
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W. Xu Y. Qiao X.‐J. Chen Y.‐P. Cai Z. Yang H.‐G. Liu 《Zeitschrift fur angewandte Ichthyologie》2015,31(5):846-854
River flow alterations caused by dams have introduced many ecological problems, in particular a decline in aquatic species such as fishes. One compensatory measure is to create a hydrological process similar to the natural state with regard to the survival requirements of the fish. In recent years, the Three Gorges Reservoir (TGR) has introduced man‐made flood by ecological operation experiments to facilitate spawning of the four major Chinese carps in the Yangtze River, China. To investigate the fish spawning activities and their responses to the TGR operation, eggs from the four major Chinese carps were sampled using conical drift nets in the middle mainstream of the Yangtze River, May to July in 2012 and 2013. Spawning timing, location, and scale of the four carps were studied and compared between the 2 years; key hydrological and environmental factors associated with spawning were determined by principal component analysis and stepwise regression analysis. Two factors were significantly positive when correlated with egg abundance: one was increasing rate of the river flow (flood amplitude), and the other was river transparency; only one factor, starting of the river flow (flooding occasions), was significantly and negatively correlated with the time of spawning. Comparison of egg abundance in one flood pulse response to different operation rules showed that flooding made by an ecological operation induced a larger scale of spawning than a conventional operation. The study implied that suitable flood conditions could produce a successful spawning event, and that the occasion and pattern of the flood process might result in different responses in fish spawning. Further research is required to develop more scientific monitoring designs in order to obtain accurate field data for both biotic and abiotic factors, and explore new research methods for egg abundance estimations combined with particle experiment and hydrodynamic modeling. This work is fundamental to improve the strategic decisions on reservoir operation and river management. 相似文献
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为了探讨齐口裂腹鱼(Schizothorax prenanti)血细胞发生发育的模式,采用Wright’s、碘酸雪夫氏(PAS)和苏丹黑B(SBB)染色方法对齐口裂腹鱼的头肾、中肾、脾和肝组织印片进行染色,了解其发生的具体组织和发育的一般过程。结果表明:齐口裂腹鱼血细胞可分为红细胞系、淋巴细胞系、单核细胞系、粒细胞系和其他细胞,且这些细胞系的发育均经过3个阶段,即原始阶段、幼稚阶段、成熟阶段。通过观察和统计不同阶段各种血细胞的形态、大小、比例及染色特征,发现原始阶段的血细胞体积较大,其中原始单核细胞最大,大小为(18.90±1.59)μm×(16.32±0.70)μm,在4种组织中原始阶段的红细胞和单核细胞在头肾中所占比例最大,分别为0.64%和0.59%,原粒细胞和原淋巴细胞分别在中肾和脾中比例最大,在肝中少量存在,此外在各组织印片中均发现血栓细胞的存在,在肝中发现巨噬细胞。因此头肾、中肾和脾是齐口裂腹鱼的主要造血组织,少量细胞在肝中产生。粒细胞发育过程中,除原始粒细胞PAS染色阴性外,其他阶段均呈阳性,且阳性随不断成熟逐渐增强;单核细胞从原单核细胞到成熟的单核细胞,PAS阳性逐渐增强;而SBB染色发现,粒细胞、淋巴细胞及单核细胞均呈阳性,未成熟的细胞染色程度不一致,成熟的细胞阳性染色最为强烈。在红细胞系发育过程中经历了细胞由大变小再变大的过程,而粒细胞和淋巴细胞发育过程仅出现由大变小的过程,在红细胞的发育过程中还出现了染色质固缩和血红蛋白增加。 相似文献
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The purpose of the study was to explore the mechanism underlying the enhanced subthalamic nucleus (STN) neural activity during exhausting exercise from the perspective of monoamine neurotransmitters and changes of their corresponding receptors. Rats were randomly divided into microdialysis and immunohistochemistry study groups. For microdialysis study, extracellular fluid of the STN was continuously collected with a microdialysis probe before, during and 90 min after one bout of exhausting exercise. Dopamine (DA) and 5-hydroxytryptamine (5-HT) levels were subsequently detected with high-performance liquid chromatography (HPLC). For immunohistochemistry study, the expression of DRD2 and HT2C receptors in the STN, before, immediately after and 90 min after exhaustion was detected through immunohistochemistry technique. Microdialysis study results showed that the extracellular DA and 5-HT neurotransmitters increased significantly throughout the procedure of exhausting exercise and the recovery period (P<0.05 or P<0.01). Immunohistochemistry study results showed that the expression levels of DRD2 and HT2C in the rat STN immediately after exhausting exercise and at the time point of 90 min after exhaustion were both higher than those of the rest condition, but the difference was not significant (P>0.05). Our results suggest that the increased extracellular DA and 5-HT in the STN might be one important factor leading to the enhanced STN neural activity and the development of fatigue during exhausting exercise. This study may essentially offer useful evidence for better understanding of the mechanism of the central type of exercise-induced fatigue. 相似文献
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The Crc protein participates in down‐regulation of the Lon gene to promote rhamnolipid production and rhl quorum sensing in Pseudomonas aeruginosa
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Artificial leaf aids analysis of chlorophyll fluorescence and P700 absorbance in studies involving microalgae
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Hongjin Qiao Xiao Fan Dong Xu Naihao Ye Jiying Wang Shaona Cao 《Phycological Research》2015,63(1):72-76
Measuring chlorophyll fluorescence and P700 absorbance has been widely used to study photosynthesis in both terrestrial plants and algae. However, in order to apply these measurement techniques to study microalgae, a concentrated suspension of algae, which is usually prepared by centrifugation, is required. In this study, instead of using centrifugation, we concentrated microalgae on a nitrocellulose membrane using filtration to create an ‘artificial leaf’ before analysis. Overall, we were able to generate values of the appropriate photosynthetic parameters that were comparable to those obtained when chlorophyll fluorescence and P700 absorbance were measured following centrifugation. There were no statistically significant differences (P > 0.05) between the artificial leaf method and the traditional cuvette method for determining chlorophyll fluorescence or P700 absorbance at appropriate chlorophyll concentrations. We were also able to reduce background noise by using a filter membrane as a carrier. Therefore, an artificial leaf has the potential to be a valuable tool for phycologists interested in studying microalgal photosynthesis by enabling them to eliminate tedious centrifugation steps. In addition, fluorometers commonly used for studying the leaves of higher plants will also be suitable for studying microalgae. 相似文献