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971.
972.
课程思政在高校实现“三全育人”体系中发挥着重要的作用,是当前高校教学改革研究的热点之一。本文以环境工程专业“环境工程微生物学”课程为例,首先从课程思政元素发掘、提升教师课程思政能力、培养学生学习兴趣和重要保障等四方面对该课程思政开展具体实践;其次从提升学生课程思政理念、提高学生课程成绩及对全校课程思政的引领等方面展现课程思政的实践成效;最后结合教学实践对课程思政进行了讨论和展望。通过上述研究,以期为环境工程专业课程思政改革提供实践路径,为发挥专业课的育人机制提供参考。  相似文献   
973.
Bamboo has been identified as a promising solution to the energy crisis and climate change as a source of biomass energy. Due to its rapid growth and high-value products, bamboo is considered as a potential source of biomass energy. Bamboo contains a significant amount of cellulose and hemicellulose, which can be converted to sugar constituents, making it an ideal raw material for energy production. This article reviews the different processes of producing bioethanol, biogas, biochar, and bio-oil from bamboo biomass using techniques such as pyrolysis, hydrothermal liquefaction, fermentation, and anaerobic digestion, and discusses the opportunities and challenges of these conversion technologies. It also reviews the main types and morphological characteristics of energy bamboo species and proposes an evaluation system for energy bamboo species, which optimizes the utilization efficiency of bamboo biomass energy and maximizes benefits by adopting appropriate methods for producing bioenergy based on the characteristics of different bamboo species.  相似文献   
974.
Several studies on the prognostic value of microRNA 142 (miR-142) in solid tumors have reported conflicting results. Therefore, the aim of this meta-analysis was to evaluate the relationship between the miR-142 and prognosis in solid tumors. A comprehensive search for relevant studies was conducted until 10 November 2020. Studies that investigated the prognostic significance of the miR-142 in solid tumors were included. The hazard ratio and 95% confidence interval were calculated using a random-effects model. All data analyses were performed using the STATA 12.0 software (Stata Corporation, College Station, TX, U.S.A.). Twenty articles involving 2451 participants were included in the meta-analysis. The results showed that high miR-142 expression was a better predictor of overall survival (OS) (HR = 0.66, 95% CI: 0.47–0.93) and disease-free/progression-free/recurrence-free survival (DFS/PFS/RFS) (HR = 0.71, 95% CI: 0.55–0.91) compared with low miR-142 expression. MiR-142 can be used as an effective prognostic marker for patients with solid tumors. Future large prospective studies are warranted to further confirm the present findings.  相似文献   
975.
One of the malignant transformation hallmarks is metabolism reprogramming, which plays a critical role in the biosynthetic needs of unchecked proliferation, abrogating cell death programs, and immunologic escape. However, the mechanism of the metabolic switch is not fully understood. Here, we found that the S-nitrosoproteomic profile of endogenous nitrogen oxide in ovarian cancer cells targeted multiple components in metabolism processes. Phosphofructokinase (PFKM), one of the most important regulatory enzymes of glycolysis, was S-nitrosylated by nitric oxide synthase NOS1 at Cys351. S-nitrosylation at Cys351 stabilized the tetramer of PFKM, leading to resist negative feedback of downstream metabolic intermediates. The PFKM-C351S mutation decreased the proliferation rate of cultured cancer cells, and reduced tumor growth and metastasis in the mouse xenograft model. These findings indicated that S-nitrosylation at Cys351 of PFKM by NOS1 contributes to the metabolic reprogramming of ovarian cancer cells, highlighting a critical role of endogenous nitrogen oxide on metabolism regulations in tumor progression.Subject terms: Cancer metabolism, Nitrosylation  相似文献   
976.
Growth factor-like phospholipids generated after corneal injury   总被引:4,自引:0,他引:4  
The present study provides evidence that growth factor-likeglycerophosphate mediators of the lysophosphatidic acid (LPA) familyare present in the aqueous humor and the lacrimal gland fluid of therabbit eye. By use of a combination of HPLC, two-dimensional TLC, massspectrometry, and the Xenopus oocytebioassay, the LPA-like phospholipids LPA, cyclic PA,alkenyl-glycerophosphate (GP), lysophosphatidylserine, and phosphatidicacid were detected as physiological constituents of the fluids bathingthe cornea. Corneal injury resulted in an increased production of someof these mediators. Alkenyl-GP, a novel member of the LPA family, hasbeen identified in postinjury aqueous humor, establishing that it isgenerated endogenously. LPA and its homologues were found to bemitogenic in freshly dissociated keratocytes from uninjured corneas.There appears to be a link between the occurrence of LPA responsivenessin keratocytes activated by injury and the increase in LPA-likeactivity in aqueous humor. These data suggest that LPA and itshomologues are involved in maintaining the integrity of the normalcornea and in promoting cellular regeneration of the injured cornea.

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977.
Recent studies have boosted our understanding of long noncoding RNAs (lncRNAs) in numerous biological processes, but few have examined their roles in somatic cell reprogramming. Through expression profiling and functional screening, we have identified that the large intergenic noncoding RNA p21 (lincRNA-p21) impairs reprogramming. Notably, lincRNA-p21 is induced by p53 but does not promote apoptosis or cell senescence in reprogramming. Instead, lincRNA-p21 associates with the H3K9 methyltransferase SETDB1 and the maintenance DNA methyltransferase DNMT1, which is facilitated by the RNA-binding protein HNRNPK. Consequently, lincRNA-p21 prevents reprogramming by sustaining H3K9me3 and/or CpG methylation at pluripotency gene promoters. Our results provide insight into the role of lncRNAs in reprogramming and establish a novel link between p53 and heterochromatin regulation.  相似文献   
978.
为了解燕山地区访花昆虫的群落结构及与其生境类型、干扰程度、海拔之间的关系, 本文采用样线法和灯诱法于2019年、2020年每年的7-8月对该地区湿地、森林、灌丛、草地、农田5种生境, 不同海拔梯度(0-1,200 m)的访花昆虫进行了采集。共采集访花昆虫1,306头, 隶属7目44科153种, 其中鳞翅目昆虫物种数最多, 半翅目昆虫个体数最多。灌丛生境的访花昆虫多样性最高。在中低海拔200-400 m段, Shannon-Wiener多样性指数、Margalef丰富度指数和Simpson优势度指数均最高。双变量回归结果表明, Shannon-Wiener多样性指数和Margalef丰富度指数分别与最暖季降水量和年降水量显著正相关(P < 0.05)。冗余分析(redundancy analysis)结果表明, 环境因子显著影响访花昆虫多样性, 但不同测度之间存在一定差异。温度和湿度均与Pielou均匀度指数呈正相关, 与Shannon-Wiener多样性指数、Margalef丰富度指数和Simpson优势度指数呈负相关; 弱干扰和中干扰程度对访花昆虫多样性影响最小, 科学管理农牧活动是保护访花昆虫多样性的关键。  相似文献   
979.
Tang  Hengfang  Wang  Peng  Wang  Han  Fang  Zhiwei  Yang  Qiang  Ni  Wenfeng  Sun  Xiaowen  Liu  Hui  Wang  Li  Zhao  Genhai  Zheng  Zhiming 《Bioprocess and biosystems engineering》2019,42(12):1923-1933

Increasing evidence shows that static magnetic fields (SMFs) can affect microbial growth metabolism, but the specific mechanism is still unclear. In this study, we have investigated the effect of moderate-strength SMFs on growth and vitamin K2 biosynthesis of Flavobacterium sp. m1-14. First, we designed a series of different moderate-strength magnetic field intensities (0, 50, 100, 150, 190 mT) and exposure times (0, 24, 48, 72, 120 h). With the optimization of static magnetic field intensity and exposure time, biomass and vitamin K2 production significantly increased compared to control. The maximum vitamin K2 concentration and biomass were achieved when exposed to 100 mT SMF for 48 h; compared with the control group, they increased by 71.3% and 86.8%, respectively. Interestingly, it was found that both the cell viability and morphology changed significantly after SMF treatment. Second, the adenosine triphosphate (ATP) and glucose-6-phosphate dehydrogenase (G6PDH) metabolism is more vigorous after exposed to 100 mT SMF. This change affects the cell energy metabolism and fermentation behavior, and may partially explain the changes in bacterial biomass and vitamin K2 production. The results show that moderate-strength SMFs may be a promising method to promote bacterial growth and secondary metabolite synthesis.

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980.
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