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Increased catabolism and decreased unsaturation of ganglioside in patients with inflammatory bowel disease 被引量:4
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作者 John J Miklavcic Glen K Shoemaker +8 位作者 Vera C Mazurak M Tom Clandinin Tasha DL Hart Kareena L Schnabl Gordon M Lees Bodil MK Larsen Oliver F Bathe Alan BR Thomson M Tom Clandinin 《World Journal of Gastroenterology》 SCIE CAS 2015年第35期10080-10090,共11页
AIM: To investigate whether accelerated catabolism of ganglioside and decreased ganglioside content contribute to the etiology of pro-inflammatory intestinal disease. METHODS: Intestinal mucosa from terminal ileum or ... AIM: To investigate whether accelerated catabolism of ganglioside and decreased ganglioside content contribute to the etiology of pro-inflammatory intestinal disease. METHODS: Intestinal mucosa from terminal ileum or colon was obtained from patients with ulcerative colitis or inflammatory Crohn's disease(n = 11) undergoing bowel resection and compared to control samples of normal intestine from patients with benign colon polyps(n = 6) and colorectal cancer(n = 12) in this observational case-control study. Gangliosides and phospholipids of intestinal mucosa were characterized by class and ceramide or fatty acid composition using liquid chromatography triple-quad mass spectrometry. Content and composition of ganglioside classes GM1, GM3, GD3, GD1 a, GT1 and GT3 were compared among subject groups. Content and composition of phospholipid classes phosphatidylcholine(PC) and phosphatidylethanolamine were compared among subject groups. Unsaturation index of individual ganglioside and phospholipid classes was computed and compared among subject groups. Ganglioside catabolism enzymes beta-hexosaminidase A(HEXA) and sialidase-3(NEU3) were measured in intestinal mucosa using western blot and compared among subject groups. RESULTS: Relative GM3 ganglioside content was 2-fold higher(P < 0.05) in intestine from patients with inflammatory bowel disease(IBD) compared to control intestine. The quantity of GM3 and ratio of GM3/GD3 was also higher in IBD intestine than control tissue(P < 0.05). Control intestine exhibited 3-fold higher(P < 0.01) relative GD1 a ganglioside content than IBD intestine. GD3 and GD1 a species of ganglioside containing three unsaturated bonds were present in control intestine, but were not detected in IBD intestine. The relative content of PC containing more than two unsaturated bonds was 30% lower in IBD intestine than control intestine(P < 0.05). The relative content of HEXA in IBD intestine was increased 1.7-fold(P < 0.05) and NEU3 was increased 8.3-fold(P < 0.01) compared to normal intestine. Intestinal mucosa in IBD is characterized by increased GM3 content, decreased GD1 a, and a reduction in polyunsaturated fatty acid constituents in GD3, GD1 a and PC.CONCLUSION: This study suggests a new paradigm by proposing that IBD occurs as a consequence of increased metabolism of specific gangliosides. 展开更多
关键词 GANGLIOSIDE PHOSPHOLIPID FATTY acid Lipid inflamma
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Modulation of immunity and inflammatory gene expression in the gut, in inflammatory diseases of the gut and in the liver by probiotics 被引量:15
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作者 Julio Plaza-Diaz Carolina Gomez-Llorente +1 位作者 Luis Fontana Angel Gil 《World Journal of Gastroenterology》 SCIE CAS 2014年第42期15632-15649,共18页
The potential for the positive manipulation of the gut microbiome through the introduction of beneficial microbes, as also known as probiotics, is currently an active area of investigation. The FAO/WHO define probioti... The potential for the positive manipulation of the gut microbiome through the introduction of beneficial microbes, as also known as probiotics, is currently an active area of investigation. The FAO/WHO define probiotics as live microorganisms that confer a health benefit to the host when administered in adequate amounts. However, dead bacteria and bacterial molecular components may also exhibit probiotic properties. The results of clinical studies have demonstrated the clinical potential of probiotics in many pathologies, such as allergic diseases, diarrhea, inflammatory bowel disease and viral infection. Several mechanisms have been proposed to explain the beneficial effects of probiotics, most of which involve gene expression regulation in specific tissues, particularly the intestine and liver. Therefore, the modulation of gene expression mediated by probiotics is an important issue that warrants further investigation. In the present paper, we performed a systematic review of the probiotic-mediated modulation of gene expression that is associated with the immune system and inflammation. Between January 1990 to February 2014, PubMed was searched for articles that were published in English using the MeSH terms &#x0201c;probiotics' and 'gene expression' combined with &#x0201c;intestines', 'liver', 'enterocytes', 'antigen-presenting cells', 'dendritic cells', 'immune system', and 'inflammation'. Two hundred and five original articles matching these criteria were initially selected, although only those articles that included specific gene expression results (77) were later considered for this review and separated into three major topics: the regulation of immunity and inflammatory gene expression in the gut, in inflammatory diseases of the gut and in the liver. Particular strains of Bifidobacteria, Lactobacilli, Escherichia coli, Propionibacterium, Bacillus and Saccharomyces influence the gene expression of mucins, Toll-like receptors, caspases, nuclear factor-&#x003ba;B, and interleukins and lead mainly to an anti-inflammatory response in cultured enterocytes. In addition, the interaction of commensal bacteria and probiotics with the surface of antigen-presenting cells in vitro results in the downregulation of pro-inflammatory genes that are linked to inflammatory signaling pathways, whereas other anti-inflammatory genes are upregulated. The effects of probiotics have been extensively investigated in animal models ranging from fish to mice, rats and piglets. These bacteria induce a tolerogenic and hyporesponsive immune response in which many genes that are related to the immune system, in particular those genes expressing anti-inflammatory cytokines, are upregulated. By contrast, information related to gene expression in human intestinal cells mediated by the action of probiotics is scarce. There is a need for further clinical studies that evaluate the mechanism of action of probiotics both in healthy humans and in patients with chronic diseases. These types of clinical studies are necessary for addressing the influence of these microorganisms in gene expression for different pathways, particularly those that are associated with the immune response, and to better understand the role that probiotics might have in the prevention and treatment of disease. 展开更多
关键词 Gene expression IMMUNITY IMMUNOTOLERANCE inflammation Microbiota PROBIOTICS GUT LIVER
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Inflammatory bowel disease: An increased risk factor for neurologic complications 被引量:6
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作者 Germán Morís 《World Journal of Gastroenterology》 SCIE CAS 2014年第5期1228-1237,共10页
Only a very few systematic studies have investigated the frequency of neurologic disorders in patients with Crohn&#x02019;s disease (CD) and ulcerative colitis (UC), which are the two main types of inflammatory bo... Only a very few systematic studies have investigated the frequency of neurologic disorders in patients with Crohn&#x02019;s disease (CD) and ulcerative colitis (UC), which are the two main types of inflammatory bowel disease (IBD). Results have been inconsistent and variable, owing to differences in case-finding methods and evaluated outcomes in different studies. The most frequent neurologic manifestations reported in CD and UC populations are cerebrovascular disease (with either arterial or venous events), demyelinating central nervous system disease, and peripheral neuropathy (whether axonal or demyelinating); however, the literature describes numerous nervous system disorders as being associated with IBD. The pathogenesis of nervous system tissue involvement in IBD has yet to be elucidated, although it seems to be related to immune mechanisms or prothrombotic states. The recently-introduced tumor necrosis factor (TNF) inhibitors have proven successful in controlling moderate to severe IBD activity. However, severe neurologic disorders associated with TNF inhibitors have been reported, which therefore raises concerns regarding the effect of anti-TNF-&#x003b1; antibodies on the nervous system. Although neurological involvement associated with IBD is rarely reported, gastroenterologists should be aware of the neurologic manifestations of IBD in order to provide early treatment, which is crucial for preventing major neurologic morbidity. 展开更多
关键词 Extraintestinal manifestations inflammatory bowel disease Multiple sclerosis NEUROPATHY STROKE Tumor necrosis factor inhibitor
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Can Na+/K+ATPase be a novel target to treat anxiety?A hint from its regulatory effect on neuroinflammation
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作者 HUANG Song-qiang ZHU Meng-yuan +2 位作者 LI Shan-shan NIE Xiao-wei BIAN Jin-song 《中国药理学与毒理学杂志》 CAS 北大核心 2021年第9期664-665,共2页
OBJECTIVE Na+/K+-ATPase(NKA)is large membrane protein expressed uni⁃versally which is indispensable for the mainte⁃nance of ionic gradient as well as neuronal excit⁃ability.The role of NKA in inflammatory regula⁃tion ... OBJECTIVE Na+/K+-ATPase(NKA)is large membrane protein expressed uni⁃versally which is indispensable for the mainte⁃nance of ionic gradient as well as neuronal excit⁃ability.The role of NKA in inflammatory regula⁃tion is still unclear.Inflammatory responses are initiated upon the activation of inflammasomes.In order to investigate the crosslink between NKA and inflammasome,NKAα1 knockout(KO)N2a cells were generated using CRISPR/Cas9 system.METHODS AND RESULTS qPCR results showed that NLRP1 and NLRP3 were upregulated in response to NKAα1 loss while both NLRC4 and AIM2 remained unaffected.Meanwhile,consistent with the change in NLRP1 and NLRP3,both the mRNA level of ASC and IL-1βwere significantly increased in NKAα1 KO cells.These data indicated that NKAα1 interfer⁃ence might influence the level of NLRP1 and NLRP3 inflammasomes in neuronal cells.Further evidence indicating the potential link between NKA and inflammasome pathway were provided using cytokine array assay where all the differen⁃tiated protein detected were closely linked to NLRP1 and NLRP3.To confirm this effect,we also observed the transcriptional levels of inflam⁃masome proteins in the brain cortex from both NKAα1+/+and NKAα1+/-mice.In line with the observation gained in NKAα1 KO cells,the mRNA level of NLRP1,NLRP3 and IL-1βwere significantly upregulated in NKAα1+/-mice brain.Interestingly,in the primary cultured astrocytes,treatment with LPS/ATP significantly reduced the mRNA and protein levels of NKAα1 expression.These data imply that a negative regulation loop between NKAα1 and inflammation may exist in the central nervous system.Since neuroinflam⁃matory mechanism is currently considered the most potential of interventions to target anxiety,we therefore perform behavioural experiments to investigate the role of NKAα1 in anxiety.Chronic restraint stress(CRS)for 10 d significantly reduced the time and frequency of entering the open arm and prolonged the retention time in the closed arm in the elevated plus-maze test.In the open field test,CRS also reduced both duration and frequency of entering into the central region.Although NKAα1 loss itself did not alter the behaviour performance in the normal condition,it exacerbated CRS-induced above behaviour abnormalities.CONCLUSION NKAα1 is regulat⁃ed upon inflammatory challenger and may be a novel target to treat anxiety. 展开更多
关键词 Na+/K+ATPase ANXIETY inflamma⁃some NEUROinflammation
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General awareness of symptoms of myocardial infarction and the need for urgent treatment:A cross-sectional,street survey in Chennai,Tamil Nadu
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作者 Thirumurugan E Gomathi K +4 位作者 Swathy P Syed Ali Afrin Ponduri Lakshmi Alekhya Jishnu B Banashree Das 《Journal of Acute Disease》 2023年第2期51-56,I0001-I0003,共9页
Objective:To investigate the golden-time-awareness of and the necessary actions in response to acute myocardial infarction among the general public.Methods:This study was conducted with the use of a descriptive resear... Objective:To investigate the golden-time-awareness of and the necessary actions in response to acute myocardial infarction among the general public.Methods:This study was conducted with the use of a descriptive research design and convenience sampling.A sample of 800 subjects,using self-structured knowledge questionnaires,was selected for data collection and analysis.The study was conducted at Dr.M.G.R.Educational and Research Institute,India,from February to November 2022.Awareness of myocardial infarction symptoms and intervention timeline(the golden time)was investigated.A multivariate logistic regression analysis was performed to identify the demographic factors affecting the recognition of the golden time of acute myocardial infarction.Results:A total of 800 subjects were included.Among the subjects,367(45.8%)were male,433(54.2%)were female,and 443(55.3%)participants failed to recognize the golden time.Our multivariate logistic regression analysis showed that people with a bachelor’s degree(OR=0.41,95%CI:0.23-0.74,P=0.03)and a high school level diploma(OR=0.55,95%CI:0.31-0.97,P=0.03)are more likely to know about myocardial infarction(golden time)than illiterate people.Additionally,people who are employed(OR=0.59,95%CI:0.41-0.85,P=0.05)are more likely to know about myocardial infarction(golden time)than those who are not.Conclusions:The majority of people in the awareness group realize that taking myocardial infarction patients to the hospital would be the best course of action.The unawareness of the ideal treatment window for myocardial infarction may cause a delay in seeking medical attention,which can lead to an increase in mortality and morbidity. 展开更多
关键词 Heart attack Intervention timeline SYMPTOMS TREATMENT Myocardial infarction Percutaneous coronary interven­tion
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经皮穴位电刺激对老年肝癌患者术后早期认知功能障碍及血清相关炎症因子的影响 被引量:1
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作者 戴敏 杨子昌 +3 位作者 胡瑞霖 李倩倩 易剑敏 虞琦 《中国中医急症》 2024年第1期85-89,共5页
目的 探讨经皮穴位电刺激(TEAS)对老年肝癌患者术后早期认知功能障碍(POCD)及血清相关炎症因子的影响。方法 选取本院收治的行手术治疗的100例肝癌患者,使用随机数字表法分为两组(各50例),TEAS组从麻醉前开始至术毕始终给予TEAS,对照组... 目的 探讨经皮穴位电刺激(TEAS)对老年肝癌患者术后早期认知功能障碍(POCD)及血清相关炎症因子的影响。方法 选取本院收治的行手术治疗的100例肝癌患者,使用随机数字表法分为两组(各50例),TEAS组从麻醉前开始至术毕始终给予TEAS,对照组不进行电流刺激。记录围术期指标、术后疼痛程度、POCD发生情况,并比较两组手术前后的血清S-100β蛋白(S-100β)、神经元特异性烯醇化酶(NSE)、白细胞介素-6(IL-6)及肿瘤坏死因子-α(TNF-α)水平变化。结果 两组的围术期指标及术后24 h VAS评分接近(P>0.05)。与对照组相比,TEAS组的丙泊酚用量、瑞芬太尼用量均明显更少(P<0.05)。与术前1 d相比,两组术后1、3、7 d MMSE评分更低,且组间对比显示TEAS组的MMSE评分更高(P<0.05)。TEAS组的POCD总发生率(24.00%)明显比对照组(68.00%)更低(P<0.05)。与术前1 d相比,两组患者术后1 d的血清S-100β、NSE、IL-6及TNF-α水平均显著升高(P<0.05),且TEAS组术后1 d的血清S-100β、NSE、IL-6及TNF-α水平较对照组更低。TEAS组术后的不良反应总发生率显著低于对照组(P<0.05)。结论 在老年肝癌患者术中行TEAS治疗可发挥镇痛作用,同时还能降低炎症因子水平,减轻脑损伤,降低POCD的发生风险,有利于患者的术后康复。 展开更多
关键词 肝部分切除术 认知功能障碍 经皮穴位电刺激 炎症因子 神经元特异性烯醇化酶
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Correlation of Abortus Imminence Cases in the First Trimester with Biochemical Markers 被引量:1
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作者 Küçükyurt Ayça Kubat Basat Dilara +2 位作者 Bingöl Bugra Berkan Artuğ Cansızlar Gülnihal İlhan Gülşah 《Open Journal of Obstetrics and Gynecology》 CAS 2023年第2期207-213,共7页
Objective: In this study, we compared the biochemical markers of imminent abortion, missed abortion, and healthy pregnant women in the first trimester to see if there were any differences. Materials and Methods: The s... Objective: In this study, we compared the biochemical markers of imminent abortion, missed abortion, and healthy pregnant women in the first trimester to see if there were any differences. Materials and Methods: The study method is prospective. Pregnant women who applied to the obstetrics clinic of Istanbul Training and Research Hospital between 01.04.22 and 31.10.22 were diagnosed with abortion imminens or missed abortion between 6 weeks and 12 weeks or had normal pregnancy follow-up, had no chronic diseases, and did not take magnesium and calcium supplements were included in the study. 20 pregnant women with missed abortion, 20 pregnant women with abortion imminens diagnosis and 20 normal pregnant women who met the criteria were included in the study. Magnesium (Mg), calcium (Ca), copper (Cu), zinc (Zn) and hemogram (CBC) levels were checked in pregnant women included in the study. Results: The Mg, Cu, Zn, and CBC values of the study participants’ women did not differ in a statistically significant way. When compared to pregnant women who had a normal pregnancy process, the difference in Ca value was found to be statistically substantially smaller in pregnant women who were diagnosed with abortion imminens and missed abortion. The findings of our study suggest that serum Ca levels be measured prior to conception or at the initial visit. Conclusion: Serum Ca levels were found to be significantly lower in the missed abortion group than in the abortus imminens and normal pregnant groups in our study (p 0.05). 展开更多
关键词 ABORtion Biochemical Markers CALCIUM Copper MAGNESIUM Missed Abor-tion Spontaneous Abortion Zinc
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生物科学与技术虚拟仿真实验教学中心的建设与应用 被引量:3
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作者 王甜 张大伟 +2 位作者 李佛生 熊莉 林宏辉 《生物学杂志》 CAS CSCD 北大核心 2024年第3期121-126,共6页
生物科学与技术虚拟仿真实验教学中心通过优秀科研项目转化以及与高新技术企业合作开发,建设了一批高质量的生物类虚拟仿真实验教学资源。多层次、多元化的资源为学生前沿科学知识学习、综合性科研训练和生物下游产业技术训练提供有利环... 生物科学与技术虚拟仿真实验教学中心通过优秀科研项目转化以及与高新技术企业合作开发,建设了一批高质量的生物类虚拟仿真实验教学资源。多层次、多元化的资源为学生前沿科学知识学习、综合性科研训练和生物下游产业技术训练提供有利环境,有效地实现教学模式的转变以及学科交叉知识的学习和延伸。全天候开放共享虚拟仿真实验教学平台,实现虚拟仿真实验教学软件、实验标准化视频、教学课件和测试题库等线上教学资源的有机整合,满足随时随地实验教学需求,支持了一系列的混合式线上线下实验教学课程开展。生物科学与技术虚拟仿真实验教学中心与国家级生物科学实验教学示范中心形成了“双中心”融合发展的创新人才培养实验教学体系,“虚实结合”的实验教学模式,提升了学生的综合科研能力与教师的业务水平,培养了满足社会需求的生物技术创新实践人才。 展开更多
关键词 虚拟仿真实验 实验教学资源 共享平台 虚实结合 人才培养
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补中益气汤联合穴位贴敷治疗术后早期炎性肠梗阻临床研究 被引量:2
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作者 石鹏 王翠敏 张宏昭 《安徽医药》 CAS 2024年第4期817-820,共4页
目的 探讨补中益气汤联合穴位贴敷治疗术后早期炎性肠梗阻(EPISBO)的临床效果。方法 纳入石家庄市中医院2019年6月至2022年3月收治的EPISBO病人110例,按随机数字表法分为对照组和治疗组(n=55),所有病人给予胃肠减压、静脉液体复苏、纠... 目的 探讨补中益气汤联合穴位贴敷治疗术后早期炎性肠梗阻(EPISBO)的临床效果。方法 纳入石家庄市中医院2019年6月至2022年3月收治的EPISBO病人110例,按随机数字表法分为对照组和治疗组(n=55),所有病人给予胃肠减压、静脉液体复苏、纠正水电解质及酸碱平衡紊乱、抗感染等基础对症治疗,对照组病人在基础对症治疗的基础上给予穴位贴敷治疗,治疗组病人在对照组的基础上加服补中益气汤,治疗周期为7 d。观察两组血清白细胞介素-1β(IL-1β)、内毒素、血管活性肽(VIP)、一氧化氮(NO)、去甲肾上腺素(NE)、5-羟色胺(5-HT)水平、胃肠功能改善时间、临床疗效以及不良反应发生率。结果 治疗组总有效率(92.73%)显著高于对照组(78.18%)(P<0.05);治疗1 d、7 d后,两组血清IL-1β、内毒素水平均显著降低,且治疗组低于对照组(P<0.05);治疗1 d、7 d后,两组血清VIP、NO、NE、5-HT水平均显著降低,且治疗7 d后治疗组血清VIP、NO、NE水平显著低于对照组(P<0.05);治疗组肠鸣音恢复时间、肛门排气恢复时间、进食恢复时间、住院时间均显著低于对照组(P<0.05)。结论 补中益气汤联合穴位贴敷对EPISBO病人的临床疗效显著,可有效降低血清IL-1β、内毒素水平,改善胃肠功能。 展开更多
关键词 肠假性梗阻 补中益气汤 穴位贴敷 手术后并发症 炎性肠梗阻 白细胞介素-1β 内毒素
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区域地震记录揭示的2023年甘肃积石山6.2级地震震源破裂过程 被引量:4
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作者 罗艳 朱音杰 高原 《地震》 CSCD 北大核心 2024年第1期189-194,共6页
基于有限断层模型反演方法,利用区域宽频带地震波形数据,反演了2023年12月18日甘肃临夏积石山6.2级地震的震源破裂过程,获得了积石山地震破裂滑动时空分布:此次地震是逆冲兼少量走滑型地震,破裂持续时间约为9 s,主体能量在前6 s释放,地... 基于有限断层模型反演方法,利用区域宽频带地震波形数据,反演了2023年12月18日甘肃临夏积石山6.2级地震的震源破裂过程,获得了积石山地震破裂滑动时空分布:此次地震是逆冲兼少量走滑型地震,破裂持续时间约为9 s,主体能量在前6 s释放,地震破裂主要沿断层走向向NW方向拓展,计算得到的标量地震矩为1.39×10^(18)N·m,相当于M_(W)6.02,破裂尺度约10 km左右,最大同震滑动量为35 cm。 展开更多
关键词 2023年积石山6.2级地震 震源破裂过程 滑动分布 有限断层
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西北地区草地贪夜蛾种群遗传多样性分析及治理策略 被引量:1
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作者 张大为 陈靖 +3 位作者 魏玉红 惠娜娜 郭致杰 罗进仓 《西北农业学报》 CAS CSCD 北大核心 2024年第2期312-320,共9页
旨在明确甘肃省草地贪夜蛾的入侵来源,并制定科学有效的防控对策。基于mtCOI基因分子标记分析中国草地贪夜蛾不同生态区8个省12个地理种群276个样品的遗传多样性指数、遗传分化系数及基因流等。结果表明,甘肃省草地贪夜蛾种群的单倍型... 旨在明确甘肃省草地贪夜蛾的入侵来源,并制定科学有效的防控对策。基于mtCOI基因分子标记分析中国草地贪夜蛾不同生态区8个省12个地理种群276个样品的遗传多样性指数、遗传分化系数及基因流等。结果表明,甘肃省草地贪夜蛾种群的单倍型多样性指数和平均核苷酸差异数分别为0.133~0.157与0.133~0.317,均低于中国周年繁殖区广东、广西、云南种群的0.157~0.819与1.033~7.705;所有种群的Tajima’s D中性检验和Fu’s F检验结果均为负值,表明草地贪夜蛾入侵中国后经历了明显的种群扩张事件。四川种群与其他种群遗传分化显著,62个种群间存在中等程度以上的基因交流。陕西略阳、陕西宁强、甘肃徽县、甘肃成县种群的有效迁入个体数和有效迁出个体数之和分别为11 860.66、11 708.65、10 878.66和10 379.32,在中国草地贪夜蛾的基因交流过程中具有中继站的作用,表明陕南汉水谷地为中国草地贪夜蛾西线北迁入侵西北的主要通道。 展开更多
关键词 mtCOI基因 草地贪夜蛾 遗传多样性 遗传分化 基因流
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Solidworks应用于《机械设计课程设计》课程教学 被引量:3
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作者 余丽 伍哲 +1 位作者 施冠羽 郭文勇 《机械设计与制造》 北大核心 2024年第1期20-22,29,共4页
在《机械设计课程设计》课程教学中引入计算机辅助设计软件Solidworks作为辅助教学手段,通过该软件特有的运动仿真功能,建立闭式齿轮传动、锥齿轮传动、开式齿轮传动、链轮绞盘机构的虚拟模型,装配各传动机构,检查、优化设计方案,实现... 在《机械设计课程设计》课程教学中引入计算机辅助设计软件Solidworks作为辅助教学手段,通过该软件特有的运动仿真功能,建立闭式齿轮传动、锥齿轮传动、开式齿轮传动、链轮绞盘机构的虚拟模型,装配各传动机构,检查、优化设计方案,实现了传动装置的运动仿真,完成了该锚机系缆装置的模拟设计,锻炼了学生的软件使用技能,增强了学生对理论知识的深入理解和应用,激发了学生对机械课程深入学习的兴趣,提高了学生的机械设计水平,同时有助于培养学生工程实践和综合应用能力,达到了预期的教学效果。 展开更多
关键词 机械设计课程设计 SOLIDWORKS 计算机辅助设计 课程教学 虚拟仿真 装配设计
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云南省蓝莓基质栽培发展现状及对策 被引量:1
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作者 苏泽春 杨燕林 +4 位作者 和加卫 杨正松 吴永斌 和志娇 余莹 《中国果树》 2024年第2期134-139,共6页
云南蓝莓凭借口感好、品质优、风味佳的优势一直备受消费者的青睐。云南省蓝莓采用基质栽培后,蓝莓产量、品质得到了进一步提升。截至2021年,云南省蓝莓种植面积已经突破6 667 hm^(2),产量约4.5万t。为了准确掌握云南省蓝莓基质栽培的... 云南蓝莓凭借口感好、品质优、风味佳的优势一直备受消费者的青睐。云南省蓝莓采用基质栽培后,蓝莓产量、品质得到了进一步提升。截至2021年,云南省蓝莓种植面积已经突破6 667 hm^(2),产量约4.5万t。为了准确掌握云南省蓝莓基质栽培的发展现状,云南省农业科学院高山水果创新团队调研了全省各个州(市)有代表性的种植企业、合作社、农民,通过查阅文献、实地调研等方式,分析了云南省蓝莓基质栽培发展现状、存在的主要问题,并提出了有关对策建议。 展开更多
关键词 蓝莓产业 基质栽培 发展现状 存在问题 对策建议
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论数字经济推动新质生产力形成的路径 被引量:19
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作者 焦方义 杜瑄 《工业技术经济》 北大核心 2024年第3期3-13,F0003,共12页
本文采用2013~2022年我国31个省(区、市)的面板数据,建立固定效应模型,从数据要素化、数字产业化、产业数字化、数字治理4个维度出发,实证检验了我国数字经济对新质生产力形成的影响及作用机制。研究发现,数字经济对新质生产力的形成有... 本文采用2013~2022年我国31个省(区、市)的面板数据,建立固定效应模型,从数据要素化、数字产业化、产业数字化、数字治理4个维度出发,实证检验了我国数字经济对新质生产力形成的影响及作用机制。研究发现,数字经济对新质生产力的形成有显著的正向影响,且在我国东部地区最为明显,中部地区次之,西部地区较为不明显。灰色关联度分析表明,战略性新兴产业和未来产业发展基础与我国新质生产力水平关联度最强。考察作用机制发现,数字产业化、产业数字化、数字治理是我国数字经济发展推动新质生产力形成的有效路径。大力发展数字化产业,促进数字技术创新;加快产业数字化转型升级,构建现代产业体系;提升数字治理能力,缩小新质生产力地区差距,成为推动我国新质生产力形成的重要政策启示。 展开更多
关键词 新质生产力 数字经济 数据要素化 数字产业化 产业数字化 数字治理
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中国竞技体操后备人才培养多元共治的影响因素研究 被引量:2
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作者 吕万刚 季彦霞 《成都体育学院学报》 北大核心 2024年第3期1-10,共10页
文章主要采用建构式案例研究方法,以扎根理论编码技术为辅助,对参与竞技体操后备人才培养治理的组织进行多案例分析,构建出竞技体操后备人才培养多元共治影响因素的理论框架。研究发现:竞技体操后备人才培养多元共治的影响因素包括价值... 文章主要采用建构式案例研究方法,以扎根理论编码技术为辅助,对参与竞技体操后备人才培养治理的组织进行多案例分析,构建出竞技体操后备人才培养多元共治影响因素的理论框架。研究发现:竞技体操后备人才培养多元共治的影响因素包括价值认同、资源投入、合作机制、组织能力和制度环境。其中,价值认同是实现竞技体操后备人才培养多元共治的原动力;资源投入和合作机制均对多元共治绩效产生正向的促进作用;组织能力和制度环境通过与其他因素产生交互作用而对竞技体操后备人才培养多元共治绩效产生正向的促进作用。 展开更多
关键词 竞技体操 后备人才 多元共治 影响因素 体教融合
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刈割对三尖叶猪屎豆养分积累与再生性的影响 被引量:1
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作者 赵志平 杨丽萍 +1 位作者 刘忠妹 杨春霞 《南方农业学报》 CAS CSCD 北大核心 2024年第1期169-178,共10页
【目的】探究三尖叶猪屎豆养分积累、再生性对刈割方式(刈割时期和频次)和留茬高度的响应,为橡胶园覆盖绿肥管理提供理论和技术指导。【方法】在树龄为3年的橡胶园中设12个处理:年刈割时期和频次为营养期刈割1次和2次、花期刈割1次,每... 【目的】探究三尖叶猪屎豆养分积累、再生性对刈割方式(刈割时期和频次)和留茬高度的响应,为橡胶园覆盖绿肥管理提供理论和技术指导。【方法】在树龄为3年的橡胶园中设12个处理:年刈割时期和频次为营养期刈割1次和2次、花期刈割1次,每个刈割时期和频次留茬高度为20.0、30.0、40.0和50.0 cm,监测不同刈割方式和留茬高度三尖叶猪屎豆的产量及干物质、氮、磷、钾、钙和镁积累量,以及刈割后1~4个月的萌发再生情况。【结果】刈割方式对三尖叶猪屎豆产量、干物质和养分积累量均具有显著影响(P<0.05,下同),营养期刈割2次/年处理三尖叶猪屎豆的产量、干物质和养分积累量均显著高于营养期刈割1次/年和花期刈割1次/年处理,产量分别提高102.44%~159.62%和54.96%~149.71%,干物质积累量分别提高103.19%~161.44%和50.46%~142.72%,氮积累量分别提高102.44%~159.62%和53.58%~209.70%,磷积累量分别提高100.44%~161.62%和-1.52%~65.73%,钾积累量分别提高101.42%~160.64%和-14.95%~108.59%,钙积累量分别提高104.42%~157.64%和46.65%~206.53%,镁积累量分别提高99.62%~155.44%和81.62%~223.57%。留茬高度对三尖叶猪屎豆产量、干物质和养分积累量具有显著影响,其中,花期刈割1次/年处理、留茬高度30.0 cm三尖叶猪屎豆的产量、干物质和养分积累量均最高;营养期刈割2次/年处理、留茬高度40.0 cm三尖叶猪屎豆的产量、干物质和养分积累量及再生性均最佳。方差分析结果表明,刈割方式和留茬高度及其互作,对猪屎豆的干物质和养分积累量均具有极显著影响(P<0.01)。【结论】刈割方式和留茬高度均显著影响三尖叶猪屎豆的产量、干物质和养分积累量及再生性。橡胶园间种三尖叶猪屎豆的最佳刈割方式为营养期刈割2次/年,留茬高度40.0 cm。 展开更多
关键词 三尖叶猪屎豆 刈割时期 刈割频次 留茬高度 产量 养分积累 再生性
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高职院校科研平台服务地方效能评价体系建设研究 被引量:1
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作者 吴玺玫 曹明 宋志敏 《中国职业技术教育》 北大核心 2024年第1期79-86,95,共9页
科教融汇新战略要求高职院校必须高度重视科研平台建设实效。面对高职院校科研平台建设层次低、体量小,重数量、轻成效,重管理、轻评价的现实问题,选择科研平台服务地方发展效能研究评价标准,有助于明确科研平台发展方向,增强发展动力,... 科教融汇新战略要求高职院校必须高度重视科研平台建设实效。面对高职院校科研平台建设层次低、体量小,重数量、轻成效,重管理、轻评价的现实问题,选择科研平台服务地方发展效能研究评价标准,有助于明确科研平台发展方向,增强发展动力,拓展发展空间。以破除“五唯”分类评价,定性定量综合考量,科学容错理性评价为原则,从平台效能目标推导评价指标体系,多元化选定评价主体,从目标设定、机构运行、有效投入、创新产出、收益影响等维度分类设计评价指标和测评点,创新性构建了高职院校科研平台服务地方效能评价体系。 展开更多
关键词 高职院校 科研平台 建设效能 评价体系
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金刚石砂轮与金刚石滚轮磨削接触的声发射监测 被引量:1
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作者 赵华东 刘勇 +1 位作者 朱振伟 张瑞 《机械设计与制造》 北大核心 2024年第2期174-178,共5页
为了实现金刚石砂轮磨削加工金刚石滚轮过程的自动化,需要对磨削接触状态进行准确识别。由于磨削过程中材料去除率较小导致声发射信号幅值变化不显著,仅用有效值对磨削接触状态识别的准确性受噪声影响很大。针对此问题,通过模态分解和... 为了实现金刚石砂轮磨削加工金刚石滚轮过程的自动化,需要对磨削接触状态进行准确识别。由于磨削过程中材料去除率较小导致声发射信号幅值变化不显著,仅用有效值对磨削接触状态识别的准确性受噪声影响很大。针对此问题,通过模态分解和相关性分析相结合的方法对采集的声发射信号进行处理,再计算各分量的有效值和方差值完成特征提取,最后利用支持向量机对磨削接触状态进行识别。实际应用发现:该方法对滚轮的磨削接触状识别准确率达到了98.3%,准确实现了对磨削接触状态的识别。 展开更多
关键词 金刚石滚轮 金刚石砂轮 声发射 模态分解 特征提取 磨削接触状态识别
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冻融环境下再生混凝土毛细吸水特性研究 被引量:1
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作者 肖前慧 师姗姗 +2 位作者 邱继生 李蕾蕾 武哲 《冰川冻土》 CSCD 2024年第3期909-918,共10页
本文采用ASTM C1585-13水工混凝土毛细吸水标准试验方法,研究了冻融循环和再生混凝土粗骨料取代率(0%、20%、40%和60%)对再生混凝土(RAC)毛细吸水性能的影响,建立了冻融环境下RAC初期毛细吸水率的预测模型,并结合非饱和毛细理论,建立了... 本文采用ASTM C1585-13水工混凝土毛细吸水标准试验方法,研究了冻融循环和再生混凝土粗骨料取代率(0%、20%、40%和60%)对再生混凝土(RAC)毛细吸水性能的影响,建立了冻融环境下RAC初期毛细吸水率的预测模型,并结合非饱和毛细理论,建立了RAC在不同冻融循环次数下相对含水量分布预测模型。结果表明:冻融环境相同时,RAC的累计吸水量和初期毛细吸水率随再生粗骨料取代率的增加而变大;再生粗骨料取代率相同时,RAC累计吸水量和初期毛细吸水率随冻融循环次数的增加而变大;从经济角度来看,40%掺量的RAC抗冻性能较优。经验证,通过回归分析建立的冻融损伤下RAC初期毛细吸水率预测模型,计算精度较高,可用于预测RAC的毛细吸水性能,为RAC的抗冻耐久性评价提供理论依据。 展开更多
关键词 再生混凝土 毛细吸水 冻融环境 累计吸水量 预测模型 微观结构
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艾司洛尔对急性心肌梗死PCI患者炎性因子及血清miR-29a、GDF-15的影响
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作者 杨树涵 任彦锋 +2 位作者 王增夏 邢永生 王志方 《医学研究与战创伤救治》 CAS 北大核心 2024年第6期622-626,共5页
目的 探究艾司洛尔对急性前壁ST段抬高型心肌梗死经皮冠状动脉介入(PCI)术患者的治疗效果,以及对患者炎性因子及血清微小核糖核酸-29a(miR-29a)、生长分化因子-15(GDF-15)的影响。方法 前瞻性选取2021年4月至2023年6月于新乡市中心医院... 目的 探究艾司洛尔对急性前壁ST段抬高型心肌梗死经皮冠状动脉介入(PCI)术患者的治疗效果,以及对患者炎性因子及血清微小核糖核酸-29a(miR-29a)、生长分化因子-15(GDF-15)的影响。方法 前瞻性选取2021年4月至2023年6月于新乡市中心医院行PCI术治疗的120例急性前壁ST段抬高型心肌梗死患者。按照随机数字表法分为艾司洛尔组和对照组,每组60例。对照组予以常规治疗,艾司洛尔组在常规治疗基础上予以艾司洛尔注射液治疗24 h,比较两组安全性、心功能指标、炎性因子水平、心肌酶学、miR-29a、GDF-15的差异。结果 两组在症状性低血压、症状性心动过缓以及恶性心律失常发生率方面比较差异没有统计学意义(P>0.05)。两组治疗1周后左心室射血分数与治疗前比较升高,左心室收缩末期容积指数、左心室舒张末期内径和BNP与治疗前比较降低(P<0.05);且艾司洛尔组治疗1周后左心室射血分数、左心室收缩末期容积指数、左心室舒张末期内径和BNP的变化优于对照组(P<0.05)。两组治疗1周后CRP、髓过氧化物酶、IL-6、CK-MB、cTnI与治疗前比较均降低(P<0.05);且艾司洛尔组治疗1周后CRP、髓过氧化物酶、IL-6、cTnI的变化均优于对照组(P<0.05)。重复测量分析结果显示,两组治疗3 d、1周miR-29a、GDF-15与治疗前相比均降低(P<0.05),且治疗1周miR-29a、GDF-15低于治疗3 d(P<0.05)。艾司洛尔组治疗3 d、治疗1周miR-29a、GDF-15优于对照组(P<0.05)。结论 艾司洛尔应用于行PCI术的急性前壁ST段抬高型心肌梗死患者可有效改善心功能,降低炎性因子水平,减少心肌损伤,并降低血清miR-29a、GDF-15水平,同时安全性较好。 展开更多
关键词 急性前壁ST段抬高型心肌梗死 经皮冠状动脉介入 艾司洛尔 安全性 炎性因子 miR-29a GDF-15
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