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61.
尾叶桉人工林生物量和生产力的研究 总被引:24,自引:0,他引:24
按径级标准木法测定了尾叶桉(Eucalyptus urophylla)器官生物量,建立了林木器官干重(w)与胸径和树高(D^3H)关系的相对生长方程,进而计算出尾叶桉林分的生物量和生产力。结果表明:东门林场10年生尾叶桉人工林平均生物量为144.85t hm^2,各器官生物量的在小序列为:干材(71.69%)〉根(14.21%)〉皮)7.99%)〉枝(4.71%)〉叶(4.71%)〉叶(1.40% 相似文献
62.
A reinvestigation of the alphatic nitro-compounds in Astragalus canadensis resulted in the identification of two new esters of glucose with 3-nitropropanoic acid and 5-oxotetrahydrofuran-3-acetic acid, together with six known conjugates of 3-nitropropanoic acid. 1H and 13CNMR data are reported for the new compounds. 相似文献
63.
M. Mahfuza Khatun Chen-Guang Liu Xin-Qing Zhao Wen-Jie Yuan Feng-Wu Bai 《Journal of industrial microbiology & biotechnology》2017,44(2):295-301
Ethanol fermentation from Jerusalem artichoke tubers was performed at elevated temperatures by the consolidated bioprocessing strategy using Saccharomyces cerevisiae MK01 expressing inulinase through cell surface display. No significant difference was observed in yeast growth when temperature was controlled at 38 and 40 °C, respectively, but inulinase activity with yeast cells was substantially enhanced at 40 °C. As a result, enzymatic hydrolysis of inulin was facilitated and ethanol production was improved with 89.3 g/L ethanol produced within 72 h from 198.2 g/L total inulin sugars consumed. Similar results were also observed in ethanol production from Jerusalem artichoke tubers with 85.2 g/L ethanol produced within 72 h from 185.7 g/L total sugars consumed. On the other hand, capital investment on cooling facilities and energy consumption for running the facilities would be saved, since regular cooling water instead of chill water could be used to cool down the fermentation system. 相似文献
64.
The resurrection flowering plant Ramonda serbica inhabits the shallow organo-mineral soil that develops in crevices on northern-facing carbonate rocks in the gorges in the
Balkan Peninsula. This type of soil represents a complex substrate whose physical and chemical properties were found to be
well suited to the most important requirements for the growth and development of R. serbica as well as for the plant’s survival in the state of anhydrobiosis in periods of drought stress. Considerable amount of organic
matter (39.4%) in the soil resulted in the high field capacity (134 ml/100 g soil) as well as the slow changes in the amount
of its available water. The suitable soil hydric status, based on the organic remains, supports the slow dehydration of this
poikilohydric plant, which is extremely important in allowing the activation of the plant’s protective mechanisms. The pH
of the soil solution was slighty alkaline (7.7) mostly due to carbonates in its crystallographic structure. The large amount
of incompletely decomposed organic debris resulted in a marked difference between total and available nutrient concentration
in the soil. Still, the adequate content of nutrients in the leaves points to efficient mineral consumption by the plant roots.
The sufficient bioavailability of nutrients and water was also improved by vesicular–arbuscular mycorrhiza detected in R. serbica roots. 相似文献
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Ti Dongdong Bai Miaomiao Li Xiaolei Wei Jianshu Chen Deyun Wu Zhiqiang Wang Yao Han Weidong 《中国科学:生命科学英文版》2021,64(3):363-371
Impaired tumor-specific effector T cells contribute to tumor progression and unfavorable clinical outcomes. As a compensatory T cell-dependent cancer immunoediting strategy, adoptive T cell therapy(ACT) has achieved encouraging therapeutic results,and this strategy is now on the center stage of cancer treatment and research. ACT involves the ex vivo stimulation and expansion of tumor-infiltrating lymphocytes(TILs) with inherent tumor reactivity or T cells that have been genetically modified to express the cognate chimeric antigen receptor or T cell receptor(CAR/TCR), followed by the passive transfer of these cells into a lymphodepleted host. Primed T cells must provide highly efficient and long-lasting immune defense against transformed cells during ACT. Anin-depth understanding of the basic mechanisms of these living drugs can help us improve upon current strategies and design better next-generation T cell-based immunotherapies. From this perspective, we provide an overview of current developments in different ACT strategies, with a focus on frontier clinical trials that offer a proof of principle. Meanwhile, insights into the determinants of ACT are discussed, which will lead to more rational, potent and widespread applications in the future. 相似文献
68.
Yong-Xin Liu Yuan Qin Tong Chen Meiping Lu Xubo Qian Xiaoxuan Guo Yang Bai 《蛋白质与细胞》2021,12(5):315-330
Advances in high-throughput sequencing(HTS)have fostered rapid developments in the field of microbiome research,and massive microbiome datasets are now being generated.However,the diversity of software tools and the complexity of analysis pipelines make it difficult to access this field.Here,we systematically summarize the advantages and limitations of micro-biome methods.Then,we recommend specific pipelines for amplicon and metagenomic analyses,and describe commonly-used software and databases,to help researchers select the appropriate tools.Furthermore,we introduce statistical and visualization methods suit-able for microbiome analysis,including alpha-and beta-diversity,taxonomic composition,difference compar-isons,correlation,networks,machine learning,evolu-tion,source tracing,and common visualization styles to help researchers make informed choices.Finally,a step-by-step reproducible analysis guide is introduced.We hope this review will allow researchers to carry out data analysis more effectively and to quickly select the appropriate tools in order to efficiently mine the bio-logical significance behind the data. 相似文献
69.
Yi Guo Dandan Bai Wenqiang Liu Yingdong Liu Yalin Zhang Xiaochen Kou Jiayu Chen Hong Wang Xiaoming Teng Ji Zuo Shaorong Gao 《Aging cell》2021,20(9)
Parental age at first pregnancy is increasing worldwide. The offspring of aged father has been associated with higher risk of several neuropsychiatric disorders, such as schizophrenia and autism, but the underlying mechanism remains elusive. Here we report that advanced paternal age in mice alters the profile of transfer RNA‐derived small RNAs (tsRNAs). Injection of sperm tsRNAs from aged male mice into zygotes induced anxiety‐like behaviors in F1 males. RNA sequencing of the cerebral cortex and hippocampus of those F1 male mice altered the gene expression of dopaminergic synapse and neurotrophin. tsRNAs from aged male mice injection also altered the neuropsychiatry‐related gene expression in two‐cell and blastocyst stage embryos. More importantly, the sperm tsRNA profile changes significantly during aging in human. The up‐regulated sperm tsRNA target genes were involved in neurogenesis and nervous system development. These results suggest that aging‐related changes of sperm tsRNA may contribute to the intergenerational transmission of behavioral traits. 相似文献
70.
Science China Life Sciences - 相似文献