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Experimental and numerical simulation study on forced ventilation and dust removal of coal mine heading surface
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作者 Haotian Zheng Bingyou Jiang +1 位作者 Haoyu Wang Yuannan Zheng 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第1期204-220,共17页
In order to study the problems of unreasonable airflow distribution and serious dust pollution in a heading surface,an experimental platform for forced ventilation and dust removal was built based on the similar princ... In order to study the problems of unreasonable airflow distribution and serious dust pollution in a heading surface,an experimental platform for forced ventilation and dust removal was built based on the similar principles.Through the similar experiment and numerical simulation,the distribution of airflow field in the roadway and the spatial and temporal evolution of dust pollution under the conditions of forced ventilation were determined.The airflow field in the roadway can be divided into three zones:jet zone,vortex zone and reflux zone.The dust concentration gradually decreases from the head to the rear of the roadway.Under the forced ventilation conditions,there is a unilateral accumulation of dust,with higher dust concentrations away from the ducts.The position of the equipment has an interception effect on the dust.The maximum error between the test value and the simulation result is 12.9%,which verifies the accuracy of the experimental results.The research results can provide theoretical guidance for the application of dust removal technology in coal mine. 展开更多
关键词 heading surface Forced ventilation Airflow field Dust pollution
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系统性红斑狼疮并发股骨头坏死危险因素列线图预测模型的建立和验证
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作者 徐文博 汪利合 +1 位作者 李松伟 史鹏博 《中国组织工程研究》 CAS 北大核心 2025年第15期3215-3226,共12页
背景:股骨头坏死是系统性红斑狼疮患者常见的并发症,若能早期对其发生风险进行预测与验证,将有助于避免或延缓股骨头坏死的发展。目的:分析系统性红斑狼疮患者并发股骨头坏死的危险因素,构建系统性红斑狼疮患者并发股骨头坏死的列线图... 背景:股骨头坏死是系统性红斑狼疮患者常见的并发症,若能早期对其发生风险进行预测与验证,将有助于避免或延缓股骨头坏死的发展。目的:分析系统性红斑狼疮患者并发股骨头坏死的危险因素,构建系统性红斑狼疮患者并发股骨头坏死的列线图预测模型并进行验证。方法:回顾性分析2013年1月至2022年12月首次就诊于河南中医药大学第一附属医院的914例系统性红斑狼疮患者的病历资料,根据是否发生股骨头坏死分为发生股骨头坏死组(n=100)和未发生股骨头坏死组(n=814)。采用单因素、LASSO回归和多因素Logistic回归分析筛选和确定系统性红斑狼疮并发股骨头坏死的危险因素。同时将数据集按照7∶3的比例随机分为训练集和测试集,并基于多因素Logistic回归分析结果,构建系统性红斑狼疮并发股骨头坏死的列线图预测模型。同时,使用受试者工作特征曲线、Hosmer-Lemeshow校准曲线和决策曲线对列线图的性能进行评估。结果与结论:①股骨头坏死组与未发生股骨头坏死组患者在系统性红斑狼疮病程、系统性红斑狼疮疾病活动度评分、狼疮性肾炎、呼吸系统受累、胃肠道受累、干燥综合征、骨质疏松、抗核糖核蛋白抗体阳性、补体C3降低、环磷酰胺、吗替麦考酚酯、生物抑制剂、糖皮质激素最大日剂量、糖皮质激素冲击治疗方面差异有显著性意义(P<0.05);②采用LASSO回归分析方法筛选出10个与系统性红斑狼疮并发股骨头坏死风险相关的预测变量,将其纳入多因素Logistic回归分析,结果显示系统性红斑狼疮病程、呼吸系统受累、干燥综合征、骨质疏松、抗核糖核蛋白抗体阳性、环磷酰胺、吗替麦考酚酯、生物抑制剂、糖皮质激素最大日剂量是系统性红斑狼疮患者发生股骨头坏死的独立危险因素(P<0.05);③训练集中预测发生风险的受试者工作特征曲线下面积为0.802(95%CI=0.742-0.862),测试集预测发生股骨头坏死风险受试者工作特征曲线下面积为0.811(95%CI=0.745-0.876);Hosmer-Lemeshow校准曲线拟合度较好(训练集,P=0.447;验证集,P=0.870);决策曲线显示使用列线图预测模型预测系统性红斑狼疮患者发生股骨头坏死的风险是有益的;④月经异常为女性系统性红斑狼疮患者并发股骨头坏死的危险因素之一;⑤此次研究结果提示,系统性红斑狼疮并发股骨头坏死的危险因素是多因素的,同时建立了一个包含9个危险因素的列线图预测模型,可将其用于预测系统性红斑狼疮患者发生股骨头坏死的风险;此外,首次报道了月经异常为女性系统性红斑狼疮并发股骨头坏死的危险因素之一。 展开更多
关键词 系统性红斑狼疮 股骨头坏死 危险因素 列线图 预测模型 月经异常 LASSO回归 多因素Logistic回归
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QTL Mapping of Heading stage for Photoperiodthermo Sensitive Male Sterile Line BS366 in Wheat 被引量:3
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作者 张立平 徐小芹 +2 位作者 赵昌平 苑少华 郭玉平 《Agricultural Science & Technology》 CAS 2010年第6期45-48,共4页
[Objective]The study aimed to map QTLs(Quantitative trait loci)of heading stage for phtopeiod-thermo sensitive male sterile line BS366 in wheat.[Method] A population of 234 doubled haploid derived from the cross bet... [Objective]The study aimed to map QTLs(Quantitative trait loci)of heading stage for phtopeiod-thermo sensitive male sterile line BS366 in wheat.[Method] A population of 234 doubled haploid derived from the cross between BS366 and Baiyu149 was planted in Beijing and Funan in 2007,respectively.We used composite interval mapping(CIM)method to analyse the QTLs for heading stage.[Result]We detected 15 QTLs for heading stage.8 QTLs were detected in both Beijing and Funan,which were located on 1B,2A,2D,3B(2 loci),6B(2 loci)and 7B.A single QTL accounted for 2.42%-10.98% of pheotypic varience.[Conclusion] Eight QTLs which were detected under two environments could be applied for marker-assisted breeding and improvement of BS366.The QTL on chromosome 1B was new for heading stage,which enriches the QTL resource. 展开更多
关键词 Wheat(Triticum aestivum L.) heading stage QTL
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Investigation on the Sterility Changeover of Male Sterility Line CMS7311 in Heading Chinese Cabbage 被引量:12
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作者 张鲁刚 郝东方 《Acta Botanica Sinica》 CSCD 2001年第11期1123-1128,共6页
Sterility changeover induced by low temperature in male sterility line CMS7311 of heading Chinese cabbage ( Brassica campestris L. ssp. penkinsis) was investigated under constant temperature, day/night alternating tem... Sterility changeover induced by low temperature in male sterility line CMS7311 of heading Chinese cabbage ( Brassica campestris L. ssp. penkinsis) was investigated under constant temperature, day/night alternating temperature in light-growth-incubator and outdoor natural day/night alternating temperature respectively. It showed that the sterility of CMS7311 has significant change with temperature. The constant temperature of 6 - 12 degreesC was suitable to induce the changeover of sterility (CGS) of CMS7311 ; the shortest treatment time for CGS induction at this temperature was 3 d. The significant value of sterility changeover of CMS7311 occurred at the constant temperature of 6 - 9 degreesC after treatment for 6 - 9 d. The intensity of CGS was stronger under constant temperature than under alternate temperature, but the shortest treatment time inducing CGS has no difference between them. When treated for 9 d under the day/night alternating temperature of 11/7 degreesC, its sterility could also turn to normal fertility (near to sterile grade I or zero). In normal condition, the interval from the end of temperature treatment to the beginning of CGS induction was 10 - 16 d. In the condition of natural day/night alternating temperature, the lower limit of temperature for effective CGS induction was at the daily mean temperature ( DMT) of 3. 5 - 6. 8 degreesC, and the shortest treatment time which could induce the sterility changeover was also longer than that under constant temperature, being 11d at DMT of 1.5 - 3.1 degreesC. In addition, for the apical dominance, the flower bud on the first lateral branch showed the CGS 8 - 10 d later than the flower bud on the main stem under the same temperature with the same days of treatment. The intensity of CGS of CMS7311 on the first lateral branch was also weaker than the flower bud on the main stem. 展开更多
关键词 heading Chinese cabbage CMS7311 changeover of sterility (CGS) temperature sensitive
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Influence of Epistasis and QTL×Environment Interaction on Heading Date of Rice(Oryza sativa L.) 被引量:3
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作者 刘桂富 杨剑 +1 位作者 徐海明 朱军 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第7期608-615,共8页
QTLs for heading date of rice (Oryza sativa L.) with additive, epistatic, and QTL × environment (QE) interaction effects were studied using a mixed-model-based composite interval mapping (MCIM) method and a... QTLs for heading date of rice (Oryza sativa L.) with additive, epistatic, and QTL × environment (QE) interaction effects were studied using a mixed-model-based composite interval mapping (MCIM) method and a double haploid (DH) population derived from IR64/Azucena in two crop seasons. Fourteen QTLs conferring heading date in rice, which were distributed on ten chromosomes except for chromosomes 5 and 9, were detected. Among these QTLs, eight had single-locus effects, five pairs had double-locus interaction effects, and two single-loci and one pair of double-loci showed QTL × environment interaction effects. All predicted values of QTL effects varied from 1.179 days to 2.549 days, with corresponding contribution ratios of 1.04%-4.84%. On the basis of the effects of the QTLs, the total genetic effects on rice heading date for the two parents and the two superior lines were predicted, and the putative reasons for discrepancies between predicted values and observed values, and the genetic potentiality in the DH population for improvement of heading date were discussed. These results are in agreement with previous results for heading date in rice, and the results provide further information, which indicate that both epistasis and QE interaction are important genetic basis for determining heading date in rice. 展开更多
关键词 quantitative trait locus (QTL) EPISTASIS QTL ×environment interaction heading date rice (Oryza sativa L.)
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Effect of Extreme Natural High Temperature on Seed Setting Rate of Rice(Oryza sativa L.) at Heading and Flowering Stage 被引量:1
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作者 朱镇 赵庆勇 +5 位作者 张亚东 陈涛 姚姝 周丽慧 于新 王才林 《Agricultural Science & Technology》 CAS 2015年第8期1666-1671,共6页
The seed setting rates of total 198 rice cultivars (lines) at heading and flowering stage were investigated under the condition of extreme natural high tem- perature in 2013 so as to analyze the effect of extreme na... The seed setting rates of total 198 rice cultivars (lines) at heading and flowering stage were investigated under the condition of extreme natural high tem- perature in 2013 so as to analyze the effect of extreme natural high temperature on seed setting rate of different rice cultivar (line). The results showed that the contin- uous high temperature showed certain effects on the seed setting rates of tested materials, and significant differences were shown in seed setting rate among differ- ent rice cultivars (lines). The seed setting rates differed significantly among indica F1 hybrids derived from different sterile and restorer lines, indicating that the sterile and restorer lines had great effects on heat tolerances of different F~ hybrids. The cor- relation analysis showed that the seed setting rates of conventional indica restorer lines and conventional japonica rice cultivars (lines) were negatively related to the daily highest temperature (P〉0.05), and the seed setting rates of indica F1 hybrids were positively related to the seed setting rates of their restorer lines. Total four in- dica restorer lines, including Ninghuiguangkangzhan, Shuhui 527, Chenghui 3203 and Xianyin-8, and four new japonica rice cultivars (lines), including Wuyinjinghui (B2), Nanjing 4//W3660/Nanjing 44 (B12) and Wuyun 2330/JD6011 (B22) were pre- liminarily screened, and their seed setting rates were all close to the normal level (90%). The screened rice cultivars (lines) showed higher heat tolerances. 展开更多
关键词 High temperature seed setting rate heading and flowering stage RICE
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The Inheritance of Early Heading in the Rice Variety USSR5 被引量:1
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作者 江玲 徐俊锋 +4 位作者 魏祥进 王松凤 唐九友 翟虎渠 万建民 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第1期46-55,共10页
USSR5, a japonica rice variety from the former Soviet Union, is an extremely early maturing rice variety. To elucidate the genetic basis for its early heading, genetic analysis was carried out by crossing it with a se... USSR5, a japonica rice variety from the former Soviet Union, is an extremely early maturing rice variety. To elucidate the genetic basis for its early heading, genetic analysis was carried out by crossing it with a set of major gene nearly isogenic lines (NIL) and QTL-isogenic lines. The early heading of USSR5 was attributed to the presence of photoperiod-insensitive alleles at E1 and Se-1 gene, the photoperiod-sensitive inhibitor gene i-Se-1, and the dominant earliness gene Ef-1. Analysis of a backcrossed population (BCIF1) derived from the cross USSR5 x N22 indicated that two quantitative trait loci (QTL) for early heading were located on chromosomes 7 and 8, accounting for 27.4% and 11.2% of the phenotypic variance, respectively, with both early alleles originating from USSRS. From an F2 population of the same cross, early heading QTLs were detected on chromosomes 1, 2, 7, 9, and 10, with individual QTL accounting for between 4.1% and 15.4% of the phenotypic variance. Early heading alleles at four of these five QTLs originated from USSRS. A comparison of chromosomal locations suggests that one of these QTLs may be identical with the known gene Hd4 (E1). The relationship between the other QTLs and known genes for heading date are not clear. USSR5 is a promising source for propagating earliness for the development of improved early heading rice varieties. 展开更多
关键词 rice (Oryza sativa L.) heading date nearly isogenic line genotype analysis QTL mapping
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松脂醇二葡萄糖苷激活Wnt/β-catenin信号通路保护成骨细胞 被引量:1
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作者 余鹏 孟东方 +2 位作者 李慧英 刘洪飞 贺自克 《中国组织工程研究》 CAS 北大核心 2025年第2期339-346,共8页
背景:松脂醇二葡萄糖苷可以促进骨形成与骨基质的合成,加速骨组织修复,但其对成骨细胞的影响和作用机制仍需进一步探索。目的:基于Wnt/β-catenin信号通路探讨松脂醇二葡萄糖苷对地塞米松干预成骨细胞的影响和作用机制。方法:设置不同... 背景:松脂醇二葡萄糖苷可以促进骨形成与骨基质的合成,加速骨组织修复,但其对成骨细胞的影响和作用机制仍需进一步探索。目的:基于Wnt/β-catenin信号通路探讨松脂醇二葡萄糖苷对地塞米松干预成骨细胞的影响和作用机制。方法:设置不同浓度的地塞米松组和松脂醇二葡萄糖苷组对成骨细胞干预24 h,筛选最佳干预浓度;使用地塞米松、松脂醇二葡萄糖苷和Wnt/β-catenin抑制剂XAV-939对成骨细胞进行干预,设置对照组、地塞米松组、抑制剂组、松脂醇二葡萄糖苷组、松脂醇二葡萄糖苷+抑制剂组。CCK-8法检测细胞活性,检测各组细胞碱性磷酸酶和半胱氨酸天冬氨酸蛋白酶3/7酶活性,Annexin V/PI染色与EdU法检测细胞凋亡与增殖情况,Real-Time qPCR检测Wnt3a、β-catenin、c-myc、骨钙素、Ⅰ型胶原蛋白的mRNA表达水平,Western Blot检测Wnt3a、β-catenin、c-myc、骨钙素、Ⅰ型胶原蛋白的蛋白表达水平。结果与结论:①地塞米松和松脂醇二葡萄糖苷干预成骨细胞24 h后,发现浓度为10μmol/L的地塞米松细胞抑制率为实验最佳干预浓度;松脂醇二葡萄糖苷浓度在100μmol/L时,细胞增殖最为明显;②与地塞米松组比较,松脂醇二葡萄糖苷组的碱性磷酸酶活性显著增强(P<0.05),半胱氨酸天冬氨酸蛋白酶3/7酶活性显著降低(P<0.05);Annexin V/PI染色和EdU法细胞增殖检测结果表明,松脂醇二葡萄糖苷可抑制地塞米松干预后成骨细胞的凋亡,促进成骨细胞增殖;③与地塞米松组和抑制剂组比较,松脂醇二葡萄糖苷组和松脂醇二葡萄糖苷+抑制剂组中Wnt3a、β-catenin、c-myc、骨钙素、Ⅰ型胶原蛋白mRNA和蛋白表达水平均显著升高(P<0.05);④结果表明,松脂醇二葡萄糖苷可以抑制地塞米松干预后的成骨细胞凋亡,通过激活Wnt/β-catenin信号通路来保护成骨细胞活性,促进成骨细胞增殖,可能发挥延缓激素性股骨头坏死的作用。 展开更多
关键词 松脂醇二葡萄糖苷 激素性股骨头坏死 成骨细胞 细胞活性 WNT/Β-CATENIN信号通路 细胞增殖 细胞凋亡
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双髋关节MRI预测股骨头坏死塌陷风险
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作者 晋继明 郝阳泉 +4 位作者 赵汝顺 张玉婷 姜永宏 许鹏 鲁超 《中国组织工程研究》 CAS 北大核心 2025年第9期1890-1896,共7页
背景:MRI是诊断股骨头坏死的金标准,以往基于MRI图像预测股骨头坏死塌陷的方法多需要冠状面、矢状面图像联合评估。然而由于股骨头坏死好发于双侧,临床上大多医院检查时多行双侧髋关节MRI扫描,但双髋扫描仅可查看冠状面及横断面图像,难... 背景:MRI是诊断股骨头坏死的金标准,以往基于MRI图像预测股骨头坏死塌陷的方法多需要冠状面、矢状面图像联合评估。然而由于股骨头坏死好发于双侧,临床上大多医院检查时多行双侧髋关节MRI扫描,但双髋扫描仅可查看冠状面及横断面图像,难以获取矢状面图像,从而影响塌陷风险的评估。因此,建立一种应用双髋MRI可获取的图像评估早期股骨头坏死塌陷风险的方法有一定的临床实用价值。目的:建立一种应用双髋关节MRI冠状面与横断面图像评估股骨头坏死塌陷风险的方法。方法:回顾性分析2017年10月至2019年10月在西安交通大学附属红会医院门诊确诊的早期股骨头坏死患者111例(181髋)的病历资料。根据末次随访时股骨头塌陷情况分为2组,其中塌陷组69髋,未塌陷组112髋。在MRI影像系统上测量正中冠状面、横断面或其上下各一个层面图像上的坏死范围角度,以冠状面、横断面上坏死角两角之和作为联合坏死角,并取每髋3种联合坏死角的平均值得到每髋的平均联合坏死角。最后,分析3种联合坏死角及平均联合坏死角与股骨头坏死塌陷的相关性,利用受试者工作特征曲线评价4种联合坏死角预测塌陷的特异性与敏感性。结果与结论:①末次随访69髋(38.1%)发生股骨头塌陷,纳入塌陷组;112髋(61.9%)未发生塌陷进展,纳入非塌陷组;②塌陷组与未塌陷组在ARCO分期方面比较差异有显著性意义(P<0.001);在年龄、体质量指数、随访时间、性别分布、发病侧别、致病因素等方面比较差异均无显著性意义(P>0.05);③独立样本t检验结果提示,4种联合坏死角均与塌陷显著相关(P<0.0001);且ARCOⅠ期、Ⅱ期中塌陷组与未塌陷组患者的联合坏死角相比差异均有显著性意义(P<0.0001);④在受试者工作特征分析中,平均联合坏死角曲线下面积大于正中下一层面、正中层面、正中上一层面上的联合坏死角;⑤平均联合坏死角塌陷预测准确度高于正中下一层面、正中层面、正中上一层面上的联合坏死角;⑥提示平均联合坏死角对股骨头坏死塌陷风险的预测精准度较高,临床实用性较强,可考虑使用该方法对股骨头坏死塌陷风险进行预测。 展开更多
关键词 股骨头坏死 塌陷预测 MRI 冠状面 横断面 联合坏死角
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Influence Factors for Safety Full Heading of Machine-transplanted Rice Seedlings in Cool-warm Rice Area
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作者 王云华 周红萍 +3 位作者 王占红 梅贵华 平建芬 黄吉美 《Agricultural Science & Technology》 CAS 2016年第8期1796-1798,1899,共4页
[Objective] This study was conducted to discuss influence factors for safety full heading of machine-transplanted rice seedlings in cool-warm rice area. [Method] Effects of variety, seedling age and nitrogen fertilize... [Objective] This study was conducted to discuss influence factors for safety full heading of machine-transplanted rice seedlings in cool-warm rice area. [Method] Effects of variety, seedling age and nitrogen fertilizer dosage and strategy of machine-transplanted seedlings on safety full heading of machine-transplanted seedlings were investigated. [Result] During mechanized rice production in coolwarm rice area, mid-early-maturing cold-resistant varieties with growth periods no longer than 180 d could selected, and seedling age could controlled within 30-35 d; and the total amount of pure nitrogen should be less than 300 kg/hm^2, and the proportion of nitrogen fertilizer applied in later stages should be properly reduced. [Conclusion] Under this condition, safety full heading of rice is ensured, and the target yield is realized. 展开更多
关键词 RICE Machine-transplanted seedling Safety full heading Influence factors
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鹿角多肽调控SLC7A11/GPX4轴抑制地塞米松诱导的成骨细胞铁死亡
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作者 邵学坤 王成 +4 位作者 王仪 王平 邱卓雅 王欣如 孙铁锋 《中国组织工程研究》 CAS 北大核心 2025年第14期2875-2881,共7页
背景:激素性股骨头坏死与成骨细胞铁死亡密切相关,鹿角多肽可以通过抑制成骨细胞铁死亡,促进成骨细胞的存活与功能的建立,具有治疗激素性股骨头坏死的潜力,但其对成骨细胞铁死亡的调控机制尚未明确。目的:探究鹿角多肽抑制地塞米松诱导... 背景:激素性股骨头坏死与成骨细胞铁死亡密切相关,鹿角多肽可以通过抑制成骨细胞铁死亡,促进成骨细胞的存活与功能的建立,具有治疗激素性股骨头坏死的潜力,但其对成骨细胞铁死亡的调控机制尚未明确。目的:探究鹿角多肽抑制地塞米松诱导成骨细胞铁死亡的作用机制。方法:①采用不同浓度梯度的鹿角多肽与地塞米松干预MC3T3-E114细胞,CCK-8法检测细胞活性,确定鹿角多肽与地塞米松的作用浓度;②采用不同质量浓度梯度鹿角多肽干预被地塞米松(800μmol/L)处理后的MC3T3-E114细胞,分为空白对照组、地塞米松组、地塞米松+鹿角多肽组,采用CCK-8法计算不同质量浓度鹿角多肽对地塞米松(800μmol/L)干预MC3T3-E114细胞增殖的影响;③借助试剂盒检测空白对照组、地塞米松组、地塞米松+鹿角多肽组中超氧化物歧化酶活性及谷胱甘肽、丙二醛、脂质过氧化物、细胞铁、活性氧含量的变化,并应用Western blot检测谷胱甘肽过氧化物酶4、溶质载体家族7成员11蛋白的表达,验证鹿角多肽抑制铁死亡的通路。结果与结论:①CCK-8法检测细胞活性,结果确定后续实验选择以鹿角多肽(10 mg/mL)和地塞米松(800μmol/L)干预MC3T3-E114细胞处理24 h;②地塞米松干预后,丙二醛、脂质过氧化物、细胞铁、活性氧含量均升高(P<0.01),谷胱甘肽含量、超氧化物歧化酶活性均降低(P<0.01),谷胱甘肽过氧化物酶4、溶质载体家族7成员11蛋白表达降低(P<0.05-0.01);鹿角多肽干预后,上述各指标变化明显被逆转(P<0.05-0.01);③结果表明,鹿角多肽可能通过调控溶质载体家族7成员11/谷胱甘肽过氧化物酶4轴抑制成骨细胞铁死亡,发挥对激素性股骨头坏死的治疗作用。 展开更多
关键词 鹿角多肽 地塞米松 激素性股骨头坏死 抑制 成骨细胞 铁死亡
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Induced neural stem cells regulate microglial activation through Akt-mediated upregulation of CXCR4 and Crry in a mouse model of closed head injury
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作者 Mou Gao Qin Dong +3 位作者 Dan Zou Zhijun Yang Lili Guo Ruxiang Xu 《Neural Regeneration Research》 SCIE CAS 2025年第5期1416-1430,共15页
Microglial activation that occurs rapidly after closed head injury may play important and complex roles in neuroinflammation-associated neuronal damage and repair.We previously reported that induced neural stem cells ... Microglial activation that occurs rapidly after closed head injury may play important and complex roles in neuroinflammation-associated neuronal damage and repair.We previously reported that induced neural stem cells can modulate the behavior of activated microglia via CXCL12/CXCR4 signaling,influencing their activation such that they can promote neurological recovery.However,the mechanism of CXCR4 upregulation in induced neural stem cells remains unclear.In this study,we found that nuclear factor-κB activation induced by closed head injury mouse serum in microglia promoted CXCL12 and tumor necrosis factor-αexpression but suppressed insulin-like growth factor-1 expression.However,recombinant complement receptor 2-conjugated Crry(CR2-Crry)reduced the effects of closed head injury mouse serum-induced nuclear factor-κB activation in microglia and the levels of activated microglia,CXCL12,and tumor necrosis factor-α.Additionally,we observed that,in response to stimulation(including stimulation by CXCL12 secreted by activated microglia),CXCR4 and Crry levels can be upregulated in induced neural stem cells via the interplay among CXCL12/CXCR4,Crry,and Akt signaling to modulate microglial activation.In agreement with these in vitro experimental results,we found that Akt activation enhanced the immunoregulatory effects of induced neural stem cell grafts on microglial activation,leading to the promotion of neurological recovery via insulin-like growth factor-1 secretion and the neuroprotective effects of induced neural stem cell grafts through CXCR4 and Crry upregulation in the injured cortices of closed head injury mice.Notably,these beneficial effects of Akt activation in induced neural stem cells were positively correlated with the therapeutic effects of induced neural stem cells on neuronal injury,cerebral edema,and neurological disorders post–closed head injury.In conclusion,our findings reveal that Akt activation may enhance the immunoregulatory effects of induced neural stem cells on microglial activation via upregulation of CXCR4 and Crry,thereby promoting induced neural stem cell–mediated improvement of neuronal injury,cerebral edema,and neurological disorders following closed head injury. 展开更多
关键词 Akt signaling cerebral edema closed head injury Crry CXCR4 induced neural stem cell MICROGLIA NEUROINFLAMMATION
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Restless head syndrome:A retrospective study
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作者 Sanjay Prakash Varoon Vadodaria +2 位作者 Niraj Chawda Chetsi S Shah Anurag Prakash 《World Journal of Methodology》 2025年第1期51-59,共9页
BACKGROUND Restless legs syndrome(RLS)is characterized by an urge to move with an unpleasant sensation in the lower limbs.RLS typically affects the legs.However,it can also affect several other body regions,such as th... BACKGROUND Restless legs syndrome(RLS)is characterized by an urge to move with an unpleasant sensation in the lower limbs.RLS typically affects the legs.However,it can also affect several other body regions,such as the arms,abdomen,face,neck,head,and genital area.There are only a few reports of the RLS variant affecting the head.AIM To assess the epidemiological,clinical,and other aspects of the RLS variant affecting the head.METHODS We conducted a retrospective study of 17 adult patients(>18 years)who met the RLS criteria and simultaneously experienced RLS-like symptoms in the head.RESULTS The median age at which symptoms appeared was 41.6 years.Males and females were equally affected(1.1:1).All 17 patients had uncomfortable sensations in the lower legs.Insomnia or disturbed sleep was the most common comorbidity(n=16,88.2%).However,headache was the most common presenting or primary symptom(n=10,70.5%).Dizziness or an abnormal sensation in the head was the second most common presenting symptom(5 patients,29.4%).Other presenting features were leg pain,backache,and generalized body pain.All patients responded favorably to dopaminergic medications.CONCLUSION If RLS-related unpleasant sensations and pain are felt in the head,they may be misinterpreted as headache,dizziness,or psychosomatic symptoms.RLS and headaches in a subset of patients may be two phenotypic manifestations of the same disorder. 展开更多
关键词 Restless legs syndrome Restless head syndrome DOPAMINE HEADACHE MIGRAINE Tension-type headache
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三七总皂苷调控破骨细胞外泌体中差异miRNA表达抑制成骨细胞铁死亡
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作者 陶红成 曾平 +5 位作者 刘金富 田照 丁强 李晁辉 韦建杰 李豪 《中国组织工程研究》 CAS 北大核心 2025年第19期4011-4021,共11页
背景:激素性股骨头坏死多是由于长期大量使用激素所致,但具体的发病机制尚未明确,有待于进一步研究。目的:筛选出三七总皂苷干预破骨细胞来源外泌体中的差异miRNA,在此基础上构建成骨相关铁死亡调控网络,以探索激素性股骨头坏死发生的... 背景:激素性股骨头坏死多是由于长期大量使用激素所致,但具体的发病机制尚未明确,有待于进一步研究。目的:筛选出三七总皂苷干预破骨细胞来源外泌体中的差异miRNA,在此基础上构建成骨相关铁死亡调控网络,以探索激素性股骨头坏死发生的潜在机制及研究方向。方法:MTT实验检测不同浓度地塞米松和不同质量浓度三七总皂苷对Raw264.7细胞系的毒性作用;抗酒石酸酸性磷酸酶染色和TUNEL染色检测三七总皂苷对破骨细胞抑制和凋亡的影响;从三七总皂苷干预的破骨细胞中提取外泌体,对外泌体进行测序找出差异表达miRNA,通过CytoScape 3.9.1构建并可视化差异表达的miRNA与mRNA间的调控网络;通过GO分析和KEGG分析筛选候选mRNA;最后筛选出铁死亡相关的差异基因,构建铁死亡相关基因的调控网络。结果与结论:①通过MTT实验确定了适合干预Raw264.7细胞的地塞米松浓度(0.1μmol/L)和三七总皂苷质量浓度(1736.85μg/mL);②三七总皂苷对破骨细胞有抑制作用并能促进其凋亡;③从破骨细胞来源外泌体样本中鉴定出20个差异miRNA,通过靶标mRNA预测出11种成骨相关的差异miRNA,并构建了4个上调的差异表达miRNA对应于155个下调的候选mRNA以及7个下调的差异表达miRNA对应于238个上调的候选mRNA的调控网络;④在差异基因中筛选出与铁死亡相关的基因24个,最终构建了12个网络(miR-98-5p/PTGS2,miR-23b-3p/PTGS2,miR-425-5p/TFRC,miR-133a-3p/TFRC,miR-185-5p/TFRC,miR-23b-3p/NFE2L2,miR-23b-3p/LAMP2,miR-98-5p/LAMP2,miR-182-5p/LAMP2,miR-182-5p/TLR4,miR-23b-3p/ZFP36,miR-182-5p/ZFP36)。这些结果表明三七总皂苷可能通过调控破骨细胞外泌体来源miRNA的表达来调节成骨细胞铁死亡,为激素性股骨头坏死的机制研究提供新的思路。 展开更多
关键词 激素性股骨头坏死 三七总皂苷 破骨细胞 外泌体 铁死亡 调控网络
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机器学习识别激素性股骨头坏死中线粒体自噬诊断标志物及免疫浸润分析
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作者 黄柯琪 陈跃平 +1 位作者 陈尚桐 李加根 《中国组织工程研究》 CAS 北大核心 2025年第11期2402-2410,共9页
背景:线粒体自噬和激素性股骨头坏死的发生、发展关系密切,但具体生物标志物及调控机制尚未明确。目的:通过机器学习算法识别激素性股骨头坏死中线粒体自噬的关键标志物及免疫浸润分析。方法:从GEO数据库下载股骨头坏死数据集GSE123568... 背景:线粒体自噬和激素性股骨头坏死的发生、发展关系密切,但具体生物标志物及调控机制尚未明确。目的:通过机器学习算法识别激素性股骨头坏死中线粒体自噬的关键标志物及免疫浸润分析。方法:从GEO数据库下载股骨头坏死数据集GSE123568和GSE74089,分别作为训练集和验证集,在激素性股骨头坏死组和对照组之间选择差异表达基因,进行加权共表达分析。从MitoCarta 3.0数据库下载线粒体自噬相关基因,然后与差异基因和模块基因取交集。利用两种机器学习算法鉴定激素性股骨头坏死线粒体自噬关键基因,利用外部验证集进行验证。采用CIBERSORT和免疫浸润分析免疫细胞占比,单样本基因集富集分析线粒体自噬基因与免疫细胞的相关性分析。结果与结论:①差异分析共获得1163个差异基因,其中有663个上调基因和500个下调基因;加权共表达分析鉴定出4个相关模块,共1412个模块基因;②最终与线粒体自噬基因取交集初步筛选出39个交叉基因可能是疾病相关线粒体自噬基因;GO富集分析结果显示,生物过程主要涉及血红素代谢、线粒体运输、核苷酸双磷酸代谢和硫酯代谢过程,细胞组分主要涉及线粒体基质、线粒体外膜、细胞器外膜和线粒体内膜,分子功能主要涉及脂肪酸连接酶活性、铁-硫簇结合和辅酶A连接酶活性;KEGG富集分析结果共映射出6条通路,主要涉及脂肪酸降解、线粒体自噬、丁酸代谢、脂肪酸生物合成和辅因子生物合成;③经LASSO回归和随机森林算法分析最终得到4个核心基因(ALDH5A1、FBXL4、MCL1和STOM),4个核心基因和诊断列线图外部验证集的受试者工作特征曲线均大于0.9;④激素性股骨头坏死发生发展与活化的树突状细胞、骨髓来源的抑制性细胞、调节性T细胞和中心记忆CD8T细胞等免疫细胞有关;⑤结果显示,4个关键的线粒体自噬基因ALDH5A1、FBXL4、MCL1和STOM通过破骨细胞分化和免疫机制在激素性股骨头坏死进展中发挥关键作用,均具有较好的疾病预测效果,可能作为激素性股骨头坏死诊断和治疗的生物标志物。 展开更多
关键词 激素性股骨头坏死 线粒体自噬 机器学习 免疫细胞浸润 关键标志物
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后外侧胫骨平台骨折应用万向螺钉的有限元分析
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作者 胡正辉 张文 +6 位作者 衡红全 任伟志 吴晨颖 顾增辉 彭建 李柳炳 徐炜 《中国组织工程研究》 CAS 北大核心 2025年第27期5735-5742,共8页
背景:通过腓骨头上入路治疗后外侧胫骨平台骨折时,腓骨头与外侧平台间隙差无法满足所有患者行钢板后置。目的:有限元法分析腓骨头上入路治疗后外侧胫骨平台骨折过程中钢板横臂万向螺钉角度以及数量不同导致固定强度的差异。方法:选用一... 背景:通过腓骨头上入路治疗后外侧胫骨平台骨折时,腓骨头与外侧平台间隙差无法满足所有患者行钢板后置。目的:有限元法分析腓骨头上入路治疗后外侧胫骨平台骨折过程中钢板横臂万向螺钉角度以及数量不同导致固定强度的差异。方法:选用一名30岁健康成年男性志愿者膝关节至踝关节的CT图像,建立有限元模型。根据外侧锁定加压钢板是否后置分为后置组和非后置组,后置组根据2枚万向螺钉的偏移角度分为A-D组(0°,5°,10°,15°);非后置组根据2枚万向螺钉的偏移角度分为E,F组(0°,15°)。采用有限元法评估250,500,750 N载荷下的von Mises应力分布、最大von Mises应力和压缩位移,探究各组之间的力学差异。结果与结论:①有限元分析结果显示:750 N载荷水平下,内固定装置的最大压缩位移趋势为D<B=C=F<A<E,最大von Mises应力趋势为B<C<A<D<F<E,骨的最大压缩位移趋势为C=D<B<A<F<E,最大von Mises应力趋势为B<C<A<F<D<E;6组模型在250-750 N的位移和应力趋势相似;②提示通过腓骨头上入路固定后外侧胫骨平台骨折,应尽量满足钢板后置2枚螺钉固定;当术中后置钢板仅满足1枚螺钉固定时,可使用万向螺钉在0°-15°范围内后偏,增加2枚螺钉的固定概率。 展开更多
关键词 后外侧胫骨平台骨折 腓骨头上入路 有限元分析 万向螺钉 钢板后置 膝关节 应力分散 生物力学
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Applying the Principle of Dynamic Equivalence in the Translation of the Heading of News Report
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作者 赵宁 《科技信息》 2008年第25期600-,575,共2页
Nida's famous notion of Dynamic Equivalence in translation process is characterized by three stages - analysis, transfer and restructuring, which are explained in detail. The application of these principles are il... Nida's famous notion of Dynamic Equivalence in translation process is characterized by three stages - analysis, transfer and restructuring, which are explained in detail. The application of these principles are illustrated by providing step-by-step explanation on the translation process of headings of two news reports, which are selected from Far Eastern Economic Review. 展开更多
关键词 Dynamic Equivalence heading NEWS
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中药调控成骨细胞铁死亡治疗激素性股骨头坏死
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作者 张绵钰 韩杰 +2 位作者 曾浩 陈相汕 高振罡 《中国组织工程研究》 CAS 北大核心 2025年第1期185-192,共8页
背景:有研究发现成骨细胞铁死亡可作为重要的发病机制诱导激素性股骨头坏死的发生与发展。随着祖国医学的发展,有学者发现某些中药单体、中药复方及中成药等可通过多种通路机制调控成骨细胞铁死亡,最终起到治疗激素性股骨头坏死的作用... 背景:有研究发现成骨细胞铁死亡可作为重要的发病机制诱导激素性股骨头坏死的发生与发展。随着祖国医学的发展,有学者发现某些中药单体、中药复方及中成药等可通过多种通路机制调控成骨细胞铁死亡,最终起到治疗激素性股骨头坏死的作用。目的:探讨成骨细胞铁死亡与激素性股骨头坏死的关系及中草药调控成骨细胞铁死亡治疗激素性股骨头坏死的作用机制,为激素性股骨头坏死的诊治提供新的思路。方法:以“铁死亡,激素性股骨头坏死,成骨细胞,中草药,糖皮质激素,铁代谢,活性氧,谷胱甘肽过氧化物酶”为中文检索词,以“ferroptosis,Hormonal necrosis of the femoral head,osteoblast,Chinese herbal medicine,glucocorticoid,iron metabolism,ROS,GPX4”为英文检索词,检索中国知网、Pub Med、万方及维普数据库,筛选各数据库建库至2023年成骨细胞铁死亡与激素性股骨头坏死及中草药干预调控研究相关的文章,最终纳入74篇文献进行综述分析。结果与结论:(1)成骨细胞铁死亡在激素性股骨头坏死发病中起重要作用。(2)成骨细胞铁死亡的发生受到多种机制通路调控,如细胞内铁超载引起铁死亡;细胞发生脂质过氧化损伤细胞膜引起铁死亡;细胞膜上胱氨酸/谷氨酸逆向转运蛋白通过影响谷胱甘肽水平和谷胱甘肽过氧化物酶4活性,从而诱导铁死亡;细胞内发生芬顿反应产生大量活性氧引起铁死亡等。(3)中药单体淫羊藿苷等、中药复方青娥丸等及中成药补肾活血颗粒等均可通过调控成骨细胞铁死亡的发生,有助于防治激素性股骨头坏死。(4)目前关于成骨细胞铁死亡相关机制尚不明确,继续深入探明两者的作用机制,有望为临床治疗激素性股骨头坏死提供新选择。 展开更多
关键词 股骨头坏死 铁死亡 中医药 成骨细胞 糖皮质激素 铁代谢 活性氧 谷胱甘肽 谷胱甘肽过氧化物酶 脂质过氧化
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激素性股骨头坏死动物模型的造模方式和评价标准
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作者 吴秀丽 阎晓霞 +2 位作者 任之强 孙楠 李金菊 《中国组织工程研究》 CAS 北大核心 2025年第21期4560-4567,共8页
背景:激素性股骨头坏死是非创伤性股骨头坏死的关键危险因素,近年来发病率逐渐上升,但其具体发病机制尚不清楚,寻找一个合理的动物模型对于疾病研究及治疗至关重要。目的:综述近年来常用的激素性股骨头坏死动物模型,分析不同造模方式和... 背景:激素性股骨头坏死是非创伤性股骨头坏死的关键危险因素,近年来发病率逐渐上升,但其具体发病机制尚不清楚,寻找一个合理的动物模型对于疾病研究及治疗至关重要。目的:综述近年来常用的激素性股骨头坏死动物模型,分析不同造模方式和评价标准的优缺点,为后续研究提供参考。方法:以“股骨头坏死,激素性股骨头坏死,动物模型,femoral head necrosis,osteonecrosis of the femoral head,steroid-induced osteonecrosis of the femoral head,animal model”为关键词,在中国知网、万方及Pub Med等数据库中检索2013-2023年发表的文献,根据纳入标准,纳入61篇文献进行综合分析,其中英文文献38篇,中文文献23篇。结果与结论:(1)兔子、大鼠和鸡是目前在激素性股骨头坏死模型研究中应用较多的动物;(2)激素联合脂多糖或马血清建模死亡率低,模型成功率高,稳定性强;(3)组织病理学是评价模型金标准,但需要终止实验,不利于后续实验研究,所以寻找一种无创替代方法仍是未来的努力方向;(4)目前尚未探索出一种理想激素性股骨头坏死动物模型,未来研究者需继续努力早日在该领域实现突破。 展开更多
关键词 激素性股骨头坏死 组织病理学 动物模型 造模 综述
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三维有限元法在股骨头坏死中应用的可视化分析
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作者 刘雨航 李宏宇 +1 位作者 王勇 王丰幸 《中国组织工程研究》 CAS 北大核心 2025年第27期5933-5940,共8页
背景:有限元分析是一种广泛应用于工程技术领域的分析手段,但因其对复杂结构同样能做到高精度分析,在骨科领域的应用研究也逐年递增。近10年来,国内外利用有限元分析对股骨头坏死研究取得的成果数不胜数,但是尚缺乏对于当前研究现状和... 背景:有限元分析是一种广泛应用于工程技术领域的分析手段,但因其对复杂结构同样能做到高精度分析,在骨科领域的应用研究也逐年递增。近10年来,国内外利用有限元分析对股骨头坏死研究取得的成果数不胜数,但是尚缺乏对于当前研究现状和热点趋势的分析。目的:对近年来有限元法应用于股骨头坏死领域的研究现状及热点进行可视化分析。方法:从中国知网(CNKI)及Web of Science数据库中筛选出2014-2023年发表与股骨头坏死有限元分析相关的文章,利用Citespace 6.1.R6可视化分析软件对相关文献的主要研究内容进行归纳,并绘制出年度发文量、作者图谱、共被引文献、热点关键词等科学知识图谱,进行总结概括。结果与结论:①根据相关关键词检索文献后导入Citespace软件,使用软件去重功能去除重复文章后,Web of Science核心合集相关文献385篇,CNKI数据库相关文献149篇;②其中关键词共现分析发现Web of Science数据库近10年间关键词频次排名为:finite element analysis(163次)、femoral head(83次)、arthroplasty(44次)、fixation(40次)、replacement(39次),中心性排名为:finite element method(0.21)、hip joint(0.21)、stability(0.19)、fixation(0.15)、contact pressure(0.15);③CNKI数据库近10年间关键词频次排名为:有限元分析(91次)、生物力学(45次)、股骨头坏死(42次)、股骨颈骨折(33次)、内固定(16次),中心性排名为:内固定(0.45)、3d打印(0.44)、健脾活骨方(0.43)、三维重建(0.42)、股骨头坏死(0.38);④近10年在股骨头坏死领域的研究中,国内外的发展均从“静态”发展为“动态”,整体进程基本上相似,对于步态模型及风险预测研究都较为深入;此外随着国内学者对于中药研究的深入,中医药手段治疗股骨头坏死疗效也得到了很好的验证;而在近10年内医学材料及计算机技术等领域将会成为国内外研究的热点;⑤尽管国内相关领域的研究较为迟缓,仍需更多临床研究验证,但随着国内科技技术的进步,相信国内学者会在未来将股骨头坏死有限元分析真正应用到临床,起到辅助患者个体化治疗、提升远期疗效的作用。 展开更多
关键词 股骨头坏死 有限元分析 内固定 步态模拟 塌陷风险 预测 研究现状 生物力学
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