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Successful emergency surgical intervention in acute non-STsegment elevation myocardial infarction with rupture:A case report
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作者 Xing-Po Li Zi-Shan Wang +1 位作者 Hong-Xia Yu Shan-Shan Wang 《World Journal of Clinical Cases》 SCIE 2025年第4期41-47,共7页
BACKGROUND The incidence of acute myocardial infarction(AMI)is rising,with cardiac rupture accounting for approximately 2%of deaths in patients with acute ST-segment elevation myocardial infarction(STEMI).Ventricular ... BACKGROUND The incidence of acute myocardial infarction(AMI)is rising,with cardiac rupture accounting for approximately 2%of deaths in patients with acute ST-segment elevation myocardial infarction(STEMI).Ventricular free wall rupture(FWR)occurs in approximately 2%of AMI patients and is notably rare in patients with non-STEMI.Types of cardiac rupture include left ventricular FWR,ventricular septal rupture,and papillary muscle rupture.The FWR usually leads to acute cardiac tamponade or electromechanical dissociation,where standard resuscitation efforts may not be effective.Ventricular septal rupture and papillary muscle rupture often result in refractory heart failure,with mortality rates over 50%,even with surgical or percutaneous repair options.CASE SUMMARY We present a rare case of an acute non-STEMI patient who suffered sudden FWR causing cardiac tamponade and loss of consciousness immediate before undergoing coronary angiography.Prompt resuscitation and emergency open-heart repair along with coronary artery bypass grafting resulted in successful patient recovery.CONCLUSION This case emphasizes the risks of AMI complications,shares a successful treatment scenario,and discusses measures to prevent such complications. 展开更多
关键词 Acute non-ST segment elevation myocardial infarction Cardiac rupture Acute myocardial infarction Free wall rupture Case report
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IL-37对大鼠慢性子宫内膜炎的疗效
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作者 邵世清 曲长萍 +2 位作者 李好山 程海玲 王琛 《郑州大学学报(医学版)》 北大核心 2025年第1期78-82,共5页
目的:探讨IL-37对慢性子宫内膜炎(CE)大鼠的疗效。方法:选取10~12周龄体重220~240 g健康雌性SD大鼠30只,分为3组,每组10只。空白组不做药物处理;模型组和IL-37组均采用宫腔内推注苯酚胶浆方法建立CE模型,术后分别腹腔注射生理盐水1 mL/d... 目的:探讨IL-37对慢性子宫内膜炎(CE)大鼠的疗效。方法:选取10~12周龄体重220~240 g健康雌性SD大鼠30只,分为3组,每组10只。空白组不做药物处理;模型组和IL-37组均采用宫腔内推注苯酚胶浆方法建立CE模型,术后分别腹腔注射生理盐水1 mL/d或IL-37蛋白10μg/(kg·d)+生理盐水1 mL/d,连续21 d。处死大鼠,取双侧子宫,计算子宫指数,HE染色观察子宫内膜组织病理改变;免疫组化法和Western blot法检测子宫内膜组织中NLRP3、IL-1β、IL-6蛋白的表达,实时荧光定量PCR法检测3者mRNA的表达。结果:空白组、模型组和IL-37组子宫指数分别为(0.66±0.08)、(1.04±0.14)和(0.84±0.06),3组比较差异有统计学意义(P<0.001);模型组较空白组增加,IL-37组较模型组减小(P<0.001)。与空白组相比,模型组NLRP3、IL-1β、IL-6蛋白和mRNA表达水平均增加(P<0.05),IL-37组较模型组下降(P<0.05)。结论:IL-37可以明显改善CE大鼠子宫内膜炎症反应。 展开更多
关键词 IL-37 慢性子宫内膜炎 NLRP3 IL-1Β IL-6 大鼠
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重组人IL-37通过调控Wnt5a减少细颗粒物诱导的支气管上皮细胞外基质沉积
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作者 曲芳芳 徐海博 +2 位作者 齐天杰 蔡志刚 阎锡新 《中国病理生理杂志》 北大核心 2025年第1期46-53,共8页
目的:探讨重组人白细胞介素37(rhIL-37)干预对细颗粒物(PM_(2.5))暴露诱导的人支气管上皮细胞细胞外基质沉积的治疗作用及机制。方法:通过不同浓度(6.25、12.5、25和50 mg/L)的PM_(2.5)干预正常人支气管上皮细胞16HBE建立气道损伤的细... 目的:探讨重组人白细胞介素37(rhIL-37)干预对细颗粒物(PM_(2.5))暴露诱导的人支气管上皮细胞细胞外基质沉积的治疗作用及机制。方法:通过不同浓度(6.25、12.5、25和50 mg/L)的PM_(2.5)干预正常人支气管上皮细胞16HBE建立气道损伤的细胞模型,用Western blot和细胞免疫荧光检测Wnt家族成员5a(Wnt5a)表达水平,选取Wnt5a表达量最高时的PM_(2.5)浓度为最佳干预浓度。实验分为3组:PM_(2.5)+siRNA组、PM_(2.5)+Wnt5a siRNA组及control+Wnt5a siRNA,观察纤连蛋白(fibronectin)、IL-6和IL-1β的表达水平及活性氧(ROS)的产生。此外,又将实验分为PM_(2.5)+rhIL-37组、PM_(2.5)组和control组,研究rhIL-37是否能够下调Wnt5a、fibronectin、IL-6和IL-1β的表达。结果:(1)给予不同浓度(6.25、12.5、25和50 mg/L)的PM_(2.5)干预16HBE细胞24 h后,Wnt5a的表达除PM_(2.5)(50 mg/L)组,均较control组显著增加(P<0.05);在PM_(2.5)(12.5 mg/L)刺激下,Wnt5a表达最高(P<0.01)。(2)在PM_(2.5)(12.5 mg/L)干预16HBE细胞24 h后,fibronectin表达达到峰值(P<0.01)。(3)敲减Wnt5a后fibronectin和核因子E2相关因子2(Nrf2)的表达,ROS的产生,以及IL-6和IL-1β的分泌均较control组显著减少(P<0.01)。(4)rhIL-37干预后再给予PM_(2.5)刺激,Wnt5a、fibronectin和Nrf2的表达,ROS的产生,以及IL-6和IL-1β的分泌均较PM_(2.5)组显著减少(P<0.05)。结论:在体外细胞模型中,PM_(2.5)可能通过Wnt5a调控炎症反应和氧化应激,从而诱导支气管上皮细胞外基质沉积;rhIL-37通过下调Wnt5a减轻炎症反应和氧化应激,从而减少细胞外基质沉积。 展开更多
关键词 重组人白细胞介素37 空气污染物 细颗粒物 人支气管上皮细胞 Wnt5a蛋白
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Gouge stability controlled by temperature elevation and obsidian addition in basaltic faults and implications for moonquakes 被引量:1
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作者 Shutian Cao Fengshou Zhang +4 位作者 Mengke An Derek Elsworth Manchao He Hai Liu Luanxiao Zhao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第9期1273-1282,共10页
Basalt is a major component of the earth and moon crust.Mineral composition and temperature influence frictional instability and thus the potential for seismicity on basaltic faults.We performed velocitystepping shear... Basalt is a major component of the earth and moon crust.Mineral composition and temperature influence frictional instability and thus the potential for seismicity on basaltic faults.We performed velocitystepping shear experiments on basalt gouges at a confining pressure of 100 MPa,temperatures in the range of 100-400℃ and with varied obsidian mass fractions of 0-100%under wet/dry conditions to investigate the frictional strength and stability of basaltic faults.We observe a transition from velocity-neutral to velocity-weakening behaviors with increasing obsidian content.The frictional stability response of the mixed obsidian/basalt gouges is characterized by a transition from velocitystrengthening to velocity-weakening at 200℃ and another transition to velocity-strengthening at temperatures>300℃.Conversely,frictional strengths of the obsidian-bearing gouges are insensitive to temperature and wet/dry conditions.These results suggest that obsidian content dominates the potential seismic response of basaltic faults with the effect of temperature controlling the range of seismogenic depths.Thus,shallow moonquakes tend to occur in the lower lunar crust due to the corresponding anticipated higher glass content and a projected temperature range conducive to velocity-weakening behavior.These observations contribute to a better understanding of the nucleation mechanism of shallow seismicity in basaltic faults. 展开更多
关键词 Fault stability Basaltic fault Temperature elevation Obsidian content Shallow moonquakes
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Technical efficiency of cocoa farms at varying elevation levels in Davao City, Philippines: implications to sustainable upland farming systems 被引量:1
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作者 Francis Levi A.DURANO Jon Marx SARMIENTO +1 位作者 Larry N.DIGAL Pedro A.ALVIOLA IV 《Journal of Mountain Science》 SCIE CSCD 2024年第1期33-48,共16页
Elevation is one of many components that influence agriculture, and this in turn affects the level of both inputs and outputs of farmers. This article focuses on the productivity and technical efficiency of 100 cocoa ... Elevation is one of many components that influence agriculture, and this in turn affects the level of both inputs and outputs of farmers. This article focuses on the productivity and technical efficiency of 100 cocoa farms using cross-sectional data from areas ranging from 190 to 1021 m above sea level which were classified as low, medium, and high elevation in Davao City, considered as the chocolate capital of the Philippines. Using stochastic frontier analysis, the results showed that the cost of inputs per ha and the number of cocoa trees per ha significantly increase yield. Farms at high elevations were less technically efficient, as this entails lower temperatures and increased rainfall, and cocoa farming in those areas and conditions can be more challenging, especially with changes in farming practices, terrain, and distance to markets. Other significant variables were age of cocoa farms, married farmers, and age of the farmers. Older farms may be more developed, farmers who are married benefit from their spouses being able to readily contribute as farm labor, and lastly, older farmers' inefficiency may likely stem from nonadaptation of newer farming practices. With an average technical efficiency of 0.61, 0.63, and 0.26 in low, medium, and high elevation areas, respectively, farmers therefore have an incentive to improve farm practices and consider topographical variations found in high elevation areas. Recommendations for the improvement of technical efficiency of cocoa farms are better connectivity to markets, enhancing farm practices, and continuation and improvement of government programs on cocoa with an added emphasis on research. For farmers in high elevation areas, mitigating solutions such as sustainable agriculture practices and ecolabelling are key to improving efficiency and minimizing the potential negative impact on upland farming systems. Moreover, such adaptation measures may also contribute to sustainability of cocoa farming in high elevation areas. 展开更多
关键词 Cocoa farms Cobb-Douglas production function elevation Philippines Stochastic frontier analysis Technical efficiency
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Impact of primary percutaneous coronary intervention on ST-segment elevation myocardial infarction patients:A comprehensive analysis 被引量:1
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作者 Eza Nawzad Saeed Abdulsatar Kamil Faeq 《World Journal of Experimental Medicine》 2024年第1期58-69,共12页
BACKGROUND Myocardial infarction,particularly ST-segment elevation myocardial infarction(STEMI),is a key global mortality cause.Our study investigated predictors of mortality in 96 STEMI patients undergoing primary pe... BACKGROUND Myocardial infarction,particularly ST-segment elevation myocardial infarction(STEMI),is a key global mortality cause.Our study investigated predictors of mortality in 96 STEMI patients undergoing primary percutaneous coronary intervention at Erbil Cardiac Center.Multiple factors were identified influencing in-hospital mortality.Significantly,time from symptom onset to hospital arrival emerged as a decisive factor.Consequently,our study hypothesis is:"Reducing time from symptom onset to hospital arrival significantly improves STEMI prognosis."AIM To determine the key factors influencing mortality rates in STEMI patients.METHODS We studied 96 consecutive STEMI patients undergoing primary percutaneous coronary intervention(PPCI)at the Erbil Cardiac Center.Their clinical histories were compiled,and coronary evaluations were performed via angiography on admission.Data included comorbid conditions,onset of cardiogenic shock,complications during PPCI,and more.Post-discharge,one-month follow-up assessments were completed.Statistical significance was set at P<0.05.RESULTS Our results unearthed several significant findings.The in-hospital and 30-d mortality rates among the 96 STEMI patients were 11.2%and 2.3%respectively.On the investigation of independent predictors of in-hospital mortality,we identified atypical presentation,onset of cardiogenic shock,presence of chronic kidney disease,Thrombolysis In Myocardial Infarction grades 0/1/2,triple vessel disease,ventricular tachycardia/ventricular fibrillation,coronary dissection,and the no-reflow phenomenon.Specifically,the recorded average time from symptom onset to hospital arrival amongst patients who did not survive was significantly longer(6.92±3.86 h)compared to those who survived(3.61±1.67 h),P<0.001.These findings underscore the critical role of timely intervention in improving the survival outcomes of STEMI patients.CONCLUSION Our results affirm that early hospital arrival after symptom onset significantly improves survival rates in STEMI patients,highlighting the critical need for prompt intervention. 展开更多
关键词 Percutaneous coronary intervention Impact analysis Segment elevation Erbil
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外周血T淋巴细胞亚群、IL-37联合PNI对多发性骨髓瘤患者化疗效果及预后的预测价值
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作者 武少雄 党惠兵 林晓媛 《航空航天医学杂志》 2025年第1期6-9,共4页
目的探讨外周血T淋巴细胞亚群、白细胞介素-37(IL-37)联合预后营养指数(PNI)对多发性骨髓瘤(MM)患者化疗效果及预后的预测价值。方法选取2020年01月~2023年01月入院治疗的103例MM患者作为研究对象,采集治疗前患者外周血T淋巴细胞亚群、I... 目的探讨外周血T淋巴细胞亚群、白细胞介素-37(IL-37)联合预后营养指数(PNI)对多发性骨髓瘤(MM)患者化疗效果及预后的预测价值。方法选取2020年01月~2023年01月入院治疗的103例MM患者作为研究对象,采集治疗前患者外周血T淋巴细胞亚群、IL-37、PNI,探讨接受化疗的MM患者外周血T淋巴细胞亚群、IL-37、PNI对短期疗效、预后的评估价值。结果CD3^(+)、CD4^(+)、CD8^(+)、CD4^(+)/CD8^(+)、IL-37、PNI均为MM患者化疗疗效的独立影响因素(P<0.05)。CD3^(+)、CD4^(+)、CD8^(+)、CD4^(+)/CD8^(+)、IL-37、PNI曲线下面积(AUC)分别为0.719(95%CI:0.619~0.820)、0.764(95%CI:0.670~0.858)、0.732(95%CI:0.625~0.840)、0.700(95%CI:0.598~0.802)、0.779(95%CI:0.689~0.869)、0.750(95%CI:0.654~0.845),联合预测AUC为0.852(95%CI:0.777~0.926)。结论外周血T淋巴细胞亚群、IL-37、PNI水平为MM患者化疗疗效的独立影响因素,并且对MM患者预后具有较好的诊断效能。 展开更多
关键词 外周血T淋巴细胞亚群 IL-37 预后营养指数 多发性骨髓瘤 化疗 预后
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基于GPR37介导的炎症消散研究瘀血痹片对炎症性疼痛小鼠的干预作用
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作者 刘莹 张国鑫 +5 位作者 姚雪敏 王文丽 黄奥晴 王海平 朱春燕 林娜 《中国中药杂志》 北大核心 2025年第1期178-186,共9页
为了调查瘀血痹片对炎症性疼痛小鼠外周及中枢炎症消散的干预作用是否与其对G蛋白偶联受体37(GPR37)的调控有关,该研究通过足底注射完全弗氏佐剂(CFA)构建炎症性疼痛小鼠模型,假手术组注射等体积生理盐水。小鼠随机分为假手术组,模型组... 为了调查瘀血痹片对炎症性疼痛小鼠外周及中枢炎症消散的干预作用是否与其对G蛋白偶联受体37(GPR37)的调控有关,该研究通过足底注射完全弗氏佐剂(CFA)构建炎症性疼痛小鼠模型,假手术组注射等体积生理盐水。小鼠随机分为假手术组,模型组,布洛芬(91 mg·kg^(-1))组,瘀血痹片低、中、高剂量(60、120、240 mg·kg^(-1))组。造模第1~19天灌胃给药。以Von Frey法检测小鼠机械痛阈值,热板法检测热痛敏,酶联免疫吸附测定法(ELISA)检测脊髓中白细胞介素-10(IL-10)、转化生长因子-β(TGF-β)的含量,实时荧光定量PCR(qRT-PCR)及蛋白免疫印迹法检测脊髓中GPR37 mRNA及蛋白表达,免疫荧光法检测背根神经节中巨噬细胞抗原(macrosialin,又名CD68)、甘露糖受体(MRC1,又名CD206)、GPR37的表达及脊髓背角中离子钙结合衔接分子1(IBA1)、CD206、GPR37的表达。结果显示,与假手术组比较,模型组小鼠机械痛阈值显著下降,热缩足潜伏时间显著缩短,背根神经节中CD68、脊髓背角中IBA1表达明显增加,背根神经节及脊髓背角中CD206、GPR37表达明显降低,脊髓中IL-10、TGF-β含量明显减少。与模型组比较,瘀血痹片高剂量组小鼠机械痛阈值显著提高,热缩足潜伏时间显著延长,背根神经节中CD68、脊髓背角中IBA1表达明显减少,背根神经节及脊髓背角中CD206、GPR37表达明显上调,脊髓中IL-10、TGF-β含量明显增加。结果表明,瘀血痹片可通过上调CFA小鼠背根神经节及脊髓背角中GPR37的表达抑制巨噬细胞(小胶质细胞)浸润,促进巨噬细胞M2极化,提高IL-10、TGF-β的含量,促进外周及中枢炎症消散,进而发挥镇痛作用。 展开更多
关键词 瘀血痹片 炎症性疼痛 炎症消散 G蛋白偶联受体37(GPR37)
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Distribution of plant species along the elevation gradient in Pangi, a high altitude and remote eco-region in Western Himalaya, India
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作者 Anupam BHATT Amit CHAWLA 《Journal of Mountain Science》 SCIE CSCD 2024年第11期3739-3753,共15页
The Himalayan high-altitude eco-regions exhibit higher plant species diversity, and several environmental factors play a crucial role in shaping species distribution and diversity. The aim of the present study is to i... The Himalayan high-altitude eco-regions exhibit higher plant species diversity, and several environmental factors play a crucial role in shaping species distribution and diversity. The aim of the present study is to investigate the floristic composition, distribution of endemic, threatened and native taxa across the elevation zones and the effect of various environmental factors on species richness pattern along the elevation gradient in Pangi, a remote highaltitude region of Himalaya. We conducted extensive field surveys covering 31 localities and established elevational transects for assessing species distribution and the factors affecting thereof. Additionally, information on nativity, endemism, and IUCN red-list categories of threatened species were compiled from published and online resources. Data were analysed using regression model and Non-Metric MultiDimensional Scaling(NMDS). In the present study, we recorded a total of 771 plant species across the region. In regression model, the elevation and anthropogenic variables and their interaction showed significant negative effects on the species richness. Species richness was found to decrease with the increasing elevation, showing a humped shaped pattern, with maximum richness observed in the mid-elevations(2,400m to 3,300m above sea level). The pattern of distribution of native and non-native species along the elevation gradient showed opposite trends, and proportion of native species increased towards the higher elevations. Further, NMDS ordination suggests that zone-Ⅰ(2,100-2,500m asl) and zone-Ⅴ(4,001-4,500m asl) had highest differences in species composition, while zone-Ⅰ, zone-Ⅱ(2,501-3,000m asl), and zone-Ⅲ(3,001-3,500m asl) showed higher affinity with respect to their species composition. Thus, the present study revealed that remote and hitherto un-explored Pangi eco-region is rich in floristic diversity and provides pertinent information on the species distribution and composition, and various underlying factors influencing the richness patterns, which is necessary for framing suitable conservation strategies, management plans and futuristic population studies. 展开更多
关键词 elevational gradient FLORISTIC HIMALAYA IUCN NATIVE Richness pattern
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Beamspace maximum likelihood algorithm based on sum and difference beams for elevation estimation
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作者 CHEN Sheng ZHAO Yongbo +1 位作者 HU Yili PANG Xiaojiao 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第3期589-598,共10页
Beamspace super-resolution methods for elevation estimation in multipath environment has attracted significant attention, especially the beamspace maximum likelihood(BML)algorithm. However, the difference beam is rare... Beamspace super-resolution methods for elevation estimation in multipath environment has attracted significant attention, especially the beamspace maximum likelihood(BML)algorithm. However, the difference beam is rarely used in superresolution methods, especially in low elevation estimation. The target airspace information in the difference beam is different from the target airspace information in the sum beam. And the use of difference beams does not significantly increase the complexity of the system and algorithms. Thus, this paper applies the difference beam to the beamformer to improve the elevation estimation performance of BML algorithm. And the direction and number of beams can be adjusted according to the actual needs. The theoretical target elevation angle root means square error(RMSE) and the computational complexity of the proposed algorithms are analyzed. Finally, computer simulations and real data processing results demonstrate the effectiveness of the proposed algorithms. 展开更多
关键词 elevation estimation BEAMSPACE multipath environment maximum likelihood
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Comparative Study of Acute Coronary Syndrome with Persistent ST-Segment Elevation (STEMI) between Diabetics and Non-Diabetics in Dakar, Senegal
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作者 Ngoné Diaba Gaye Aliou Alassane Ngaïdé +4 位作者 Joseph Salvador Mingou Massar Wague Momar Dioum Alassane Mbaye Abdoul Kane 《World Journal of Cardiovascular Diseases》 CAS 2024年第10期631-643,共13页
Introduction: This study aimed to compare the frequency of diabetic and non-diabetic patients admitted for ST-elevation myocardial infarction (STEMI), assess their epidemiological, clinical, and paraclinical profiles,... Introduction: This study aimed to compare the frequency of diabetic and non-diabetic patients admitted for ST-elevation myocardial infarction (STEMI), assess their epidemiological, clinical, and paraclinical profiles, and evaluate their therapeutic strategies and outcomes. Methodology: A descriptive, analytical, comparative study with prospective and retrospective data collection was conducted from April 1, 2020, to March 31, 2021. Diabetic and non-diabetic patients with STEMI admitted to a cardiology department were included. STEMI diagnosis was based on clinical and electrocardiographic criteria showing persistent ST-segment elevation in at least two leads. All patients included in the study signed a written, informed consent form. Data analysis was performed using SPSS, with a p-value ≤ 0.05 considered statistically significant. Results: STEMI prevalence was 15.27%, with 37.11% of patients being diabetic and 62.89% non-diabetic. Diabetic patients had a mean age of 59.2 ± 10.9 years, while non-diabetics averaged 58 ± 13.4 years. Diabetics were predominantly female (72.2%), whereas non-diabetics were mainly male (83.6%). Smoking was less frequent among diabetics (25% vs. 47.54%), but hypertension, obesity, and sedentary lifestyle were more common. Diabetics had an average of 3.5 ± 1.1 risk factors compared to 2.6 ± 1.2 in non-diabetics. Admission delay was longer for diabetics (34.8 ± 51.6 hours vs. 23.3 ± 52.3 hours). Chest pain was the main symptom in both groups. Electrocardiograms showed that anterior and inferior infarctions were most frequent. Triple vessel disease and severe complications, such as cardiogenic shock, were more common in diabetics, who also had higher mortality (5.56% vs. 3.28%). Conclusion: Diabetic STEMI patients represent a high-risk group with distinct clinical features, longer admission delays, and a greater accumulation of cardiovascular risk factors, emphasizing the need for targeted interventions. 展开更多
关键词 Acute Coronary Syndrome with Persistent ST-Segment elevation DIABETES Senegal
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From furnace up to freezer:Elevational patterns of plant diversity in Mount Palvar,a semi-arid Irano-Turanian mountain range of southwest Asia
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作者 Atefeh GHORBANALIZADEH Moslem DOOSTMOHAMMADI 《Journal of Mountain Science》 SCIE CSCD 2024年第7期2236-2248,共13页
Much of the world's biodiversity lies in heterogeneous mountain areas with their diverse environments.As an example,Iranian montane ranges are highly diverse,particularly in the Irano-Turanian phytogeographical re... Much of the world's biodiversity lies in heterogeneous mountain areas with their diverse environments.As an example,Iranian montane ranges are highly diverse,particularly in the Irano-Turanian phytogeographical region.Understanding plant diversity patterns with increasing elevation is of high significance,not least for conservation planning.We studied the pattern of species richness,Shannon diversity,endemic richness,endemics ratio,and richness of life forms along a 3900 m elevational transect in Mount Palvar,overlooking the Lut Desert in Southeast Iran.We also analyzed the effect of environmental variables on species turnover along the vertical gradient.A total of 120 vegetation plots(10 m×10 m)were sampled along the elevational transect containing species and environmental data.To discover plant diversity pattern along the elevational gradient,generalized additive model(GAM)was used.Non-metric multidimensional scaling(NMDS)was applied for illustrating the correlation between species composition and environmental variables.We found hump-shaped pattern for species richness,Shannon diversity,endemic richness,and species richness of different life forms,but a monotonic increasing pattern for ratio of endemic species from low to high elevations.Our study confirms the humped pattern of species richness peaking at intermediate elevations along a complete elevational gradient in a semi-arid mountain.The monotonic increase of endemics ratio with elevation in our area as a case study is consistent with global increase of endemism with elevation.According to our results,temperature and precipitation are two important climatic variables that drive elevational plant diversity,particularly in seasonally dry areas.Our study suggests that effective conservation and management are needed for this low latitude mountain area along with calling for long-term monitoring for species redistribution. 展开更多
关键词 elevational gradient Biodiversity ENDEMIC Generalized additive model Hump-shaped pattern Irano-Turanian region
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Elevational and temporal patterns of pollination success in distylous and homostylous buckwheats(Fagopyrum)in the Hengduan Mountains
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作者 Ling-Yun Wu Shuang-Quan Huang Ze-Yu Tong 《Plant Diversity》 SCIE CAS CSCD 2024年第5期661-670,共10页
Reproductive strategies of sexually dimorphic plants vary in response to the environment.Here,we ask whether the sexual systems of Fagopyrum species(i.e.,selfing homostylous and out-crossing distylous)represent distin... Reproductive strategies of sexually dimorphic plants vary in response to the environment.Here,we ask whether the sexual systems of Fagopyrum species(i.e.,selfing homostylous and out-crossing distylous)represent distinct adaptive strategies to increase reproductive success in changing alpine environments.To answer this question,we determined how spatial and temporal factors(e.g.,elevation and peak flowering time)affect reproductive success(i.e.,stigmatic pollen load)in nine wild Fagopyrum species(seven distylous and two homostylous)among 28 populations along an elevation gradient of 1299-3315 m in the Hengduan Mountains,southwestern China.We also observed pollinators and conducted hundreds of hand pollinations to investigate inter/intra-morph compatibility,self-compatibility and pollen limitation in four Fagopyrum species(two distylous and two homostylous).We found that Fagopyrum species at higher elevation generally had bigger flowers and more stigmatic pollen loads;lateflowering individuals had smaller flowers and lower pollen deposition.Stigmatic pollen deposition was more variable in distylous species than in homostylous species.Although seed set was not pollenlimited in all species,we found that fruit set was much lower in distylous species,which rely on frequent pollinator visits,than in homostylous species capable of autonomous self-pollination.Our findings that pollination success increases at high elevations and decreases during the flowering season suggest that distylous and homostylous species have spatially and temporally distinct reproductive strategies related to environment-dependent pollinator activity. 展开更多
关键词 Biodiversity hotspot elevation gradient FAGOPYRUM Stigmatic pollen load Temporal pattern
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Casein kinase-2 inhibition promotes retinal ganglion cell survival after acute intraocular pressure elevation
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作者 Meng Wang Shi-Qi Yao +8 位作者 Yao Huang Jia-Jian Liang Yanxuan Xu Shaowan Chen Yuhang Wang Tsz Kin Ng Wai Kit Chu Qi Cui Ling-Ping Cen 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第5期1112-1118,共7页
Intraocular pressure elevation can induce retinal ganglion cell death and is a clinically reversible risk factor for glaucoma,the leading cause of irreversible blindness.We previously demonstrated that casein kinase-2... Intraocular pressure elevation can induce retinal ganglion cell death and is a clinically reversible risk factor for glaucoma,the leading cause of irreversible blindness.We previously demonstrated that casein kinase-2 inhibition can promote retinal ganglion cell survival and axonal regeneration in rats after optic nerve injury.To investigate the underlying mechanism,in the current study we increased the intraocular pressure of adult rats to 75 mmHg for 2 hours and then administered a casein kinase-2 inhibitor(4,5,6,7-tetrabromo-2-azabenzimidazole or 2-dimethylamino-4,5,6,7-tetrabromo-1H-benzimidazole)by intravitreal injection.We found that intravitreal injection of 4,5,6,7-tetrabromo-2-azabenzimidazole or 2-dimethylamino-4,5,6,7-tetrabromo-1H-benzimidazole promoted retinal ganglion cell survival and reduced the number of infiltrating macrophages.Transcriptomic analysis showed that the mitogen activated protein kinase signaling pathway was involved in the response to intraocular pressure elevation but was not modulated by the casein kinase-2 inhibitors.Furthermore,casein kinase-2 inhibition downregulated the expression of genes(Cck,Htrsa,Nef1,Htrlb,Prph,Chat,Slc18a3,Slc5a7,Scn1b,Crybb2,Tsga10ip,and Vstm21)involved in intraocular pressure elevation.Our data indicate that inhibition of casein kinase-2 can enhance retinal ganglion cell survival in rats after acute intraocular pressure elevation via macrophage inactivation. 展开更多
关键词 casein kinase-2 GLAUCOMA intraocular pressure elevation MACROPHAGES retinal ganglion cells
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The storage and utilization of carbohydrates in response to elevation mediated by tree organs in subtropical evergreen broad-leaved forests
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作者 Bin Xu Xueli Jiang +4 位作者 Yingying Zong G.Geoff Wang Fusheng Chen Zhenyu Zhao Xiangmin Fang 《Forest Ecosystems》 SCIE CSCD 2024年第1期52-61,共10页
Global climate change can affect tree growth and carbon sink function by influencing plant carbohydrate synthesis and utilization,while elevation can be used as an ideal setting under natural conditions to simulate cl... Global climate change can affect tree growth and carbon sink function by influencing plant carbohydrate synthesis and utilization,while elevation can be used as an ideal setting under natural conditions to simulate climate change effects.The effect of elevation on tree growth may depend on organ type.However,the allocation patterns of nonstructural and structural carbohydrates(NSCs and SCs,respectively)in different tree organs and their response to elevation remain unclear.We selected four dominant tree species,Schima superba,Castanopsis eyrei,Castanopsis fargesii and Michelia maudiae,along an elevation gradient from 609 to 1,207 m in subtropical evergreen broad-leaved forests and analyzed leaf,trunk,and fine root NSCs,carbon(C),nitrogen(N)and phosphorus(P)concentrations and the relative abundance of SCs.Leaf NSCs increased initially and then decreased,and trunk NSCs increased with increasing elevation.However,root NSCs decreased with increasing elevation.The relative abundance of SCs in leaves and trunks decreased,while the relative abundance of root SCs increased with increasing elevation.No significant correlations between SCs and NSCs in leaves were detected,while there were negative correlations between SCs and NSCs in trunks,roots,and all organs.Hierarchical partitioning analysis indicated that plant C/N and C/P were the main predictors of changes in SCs and NSCs.Our results suggest that tree organs have divergent responses to elevation and that increasing elevation will inhibit the aboveground part growth and enhance the root growth of trees.A tradeoff between the C distribution used for growth and storage was confirmed along the elevation gradient,which is mainly manifested in the"sink"organs of NSCs.Our results provide insight into tree growth in the context of global climate change scenarios in subtropical forest ecosystems. 展开更多
关键词 Nonstructural carbohydrates Structural carbohydrates elevation Subtropical evergreen broad-leaved forests Tree organs
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Changes in posterior corneal elevation after small incision lenticule extraction for different myopic diopters
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作者 Xiao-Tong Sun Yang Zhang +5 位作者 Xiao-Kun Mei Nan-Nan Zheng Ling-Zhi Niu Xiao-Li Qu Ai-Ping Song Jian Zhuo 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第3期491-498,共8页
●AIM:To study the changes and effect factors of posterior corneal surface after small incision lenticule extraction(SMILE)with different myopic diopters.●METHODS:Ninety eyes of 90 patients who underwent SMILE were i... ●AIM:To study the changes and effect factors of posterior corneal surface after small incision lenticule extraction(SMILE)with different myopic diopters.●METHODS:Ninety eyes of 90 patients who underwent SMILE were included in this retrospective study.Patients were allocated into three groups based on the preoperative spherical equivalent(SE):low myopia(SE≥-3.00 D),moderate myopia(-3.00 D>SE>-6.00 D)and high myopia(SE≤-6.00 D).Posterior corneal surfaces were measured by a Scheimpflug camera preoperatively and different postoperative times(1wk,1,3,6mo,and 1y).Posterior mean elevation(PME)at 25 predetermined points of 3 concentric circles(2-,4-,and 6-mm diameter)above the best fit sphere was analyzed.●RESULTS:All surgeries were completed uneventfully and no ectasia was found through the observation.The difference of myopia group was significant at the 2-mm ring at 1 and 3mo postoperatively(1mo:P=0.017;3mo:P=0.018).The effect of time onΔPME was statistically significant(2-mm ring:P=0.001;4-mm ring:P<0.001;6-mm ring:P<0.001).The effect of different corneal locations onΔPME was significant except 1wk postoperatively(1mo:P=0.000;3mo:P=0.000;6mo:P=0.001;1y:P=0.001).Posterior corneal stability was linearly correlated with SE,central corneal thickness,ablation depth,residual bed thickness,percent ablation depth and percent stromal bed thickness.●CONCLUSION:The posterior corneal surface changes dynamically after SMILE.No protrusion is observed on the posterior corneal surface in patients with different degrees of myopia within one year after surgery.SMILE has good stability,accuracy,safety and predictability. 展开更多
关键词 MYOPIA posterior corneal elevation corneal ectasia small incision lenticule extraction
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Productivity and technical efficiency of Robusta coffee farms at varying elevation categories in Sultan Kudarat, Philippines: implications on sustainability
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作者 Mark James S.SAGUIMPA Larry N.DIGAL 《Journal of Mountain Science》 SCIE CSCD 2024年第11期3615-3629,共15页
Elevation can affect agricultural outputs,affecting farms’productivity and efficiency.This article identified the significant production inputs influencing productivity and factors influencing technical efficiency(TE... Elevation can affect agricultural outputs,affecting farms’productivity and efficiency.This article identified the significant production inputs influencing productivity and factors influencing technical efficiency(TE)and determined the average TE scores of Robusta coffee farms at varying elevations in Sultan Kudarat,Philippines.Cross-sectional data from the Mahintana Foundation,Inc.using random stratified sampling and power analysis from September 9,2021,to January 13,2022,were used to analyze 604 farms from areas ranging from 0.33 to 1284.18 above mean sea level(amsl),classified as low,medium,and high elevation.Open-Data-Kit-based(ODK)mobile data collection systems were utilized to precisely determine the farms’coordinates and elevation.Using stochastic frontier analysis,results showed that increasing the total fertilizer amount and total trees by 1%significantly increased yield by 0.20%and 0.79%,respectively.Meanwhile,increasing the total land area by 1%,including areas unutilized for coffee farming,decreases total yield by 0.11%.Regarding TE,results showed that TE decreases by approximately 0.58%at high elevations.Meanwhile,increasing net income from coffee farming alone by 1%significantly increases TE by 0.00008%.With an average TE of 0.60,0.77,and 0.63 in low,medium,and high elevations,farms may be incentivized to improve farming practices to increase their TE further.TE improvement recommendations include promoting coffee-agroforestry systems and ecolabelling at medium elevations,such as shade-grown coffee,to promote sustainable production in Robusta coffee farms by assigning a premium to consumers demanding environmental conservation. 展开更多
关键词 Cobb-Douglas production function elevation Philippines Robusta coffee farms Stochastic frontier analysis Technical efficiency
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Performance validation of High Mountain Asia 8-meter Digital Elevation Model using ICESat-2 geolocated photons
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作者 Giribabu DANDABATHULA Subham ROY +7 位作者 Omkar Shashikant GHATAGE Vaibhav Balaso KOLASE Shwetambari SATPUTE Koushik GHOSH Sahibnoor KAUR Satyanarayana PONDARI Apurba Kumar BERA Sushil Kumar SRIVASTAV 《Journal of Mountain Science》 SCIE CSCD 2024年第8期2562-2578,共17页
High Mountain Asia(HMA),recognized as a third pole,needs regular and intense studies as it is susceptible to climate change.An accurate and high-resolution Digital Elevation Model(DEM)for this region enables us to ana... High Mountain Asia(HMA),recognized as a third pole,needs regular and intense studies as it is susceptible to climate change.An accurate and high-resolution Digital Elevation Model(DEM)for this region enables us to analyze it in a 3D environment and understand its intricate role as the Water Tower of Asia.The science teams of NASA realized an 8-m DEM using satellite stereo imagery for HMA,termed HMA 8-m DEM.In this research,we assessed the vertical accuracy of HMA 8-m DEM using reference elevations from ICESat-2 geolocated photons at three test sites of varied topography and land covers.Inferences were made from statistical quantifiers and elevation profiles.For the world’s highest mountain,Mount Everest,and its surroundings,Root Mean Squared Error(RMSE)and Mean Absolute Error(MAE)resulted in 1.94 m and 1.66 m,respectively;however,a uniform positive bias observed in the elevation profiles indicates the seasonal snow cover change will dent the accurate estimation of the elevation in this sort of test sites.The second test site containing gentle slopes with forest patches has exhibited the Digital Surface Model(DSM)features with RMSE and MAE of 0.58 m and 0.52 m,respectively.The third test site,situated in the Zanda County of the Qinghai-Tibet,is a relatively flat terrain bed,mostly bare earth with sudden river cuts,and has minimal errors with RMSE and MAE of 0.32 m and 0.29 m,respectively,and with a negligible bias.Additionally,in one more test site,the feasibility of detecting the glacial lakes was tested,which resulted in exhibiting a flat surface over the surface of the lakes,indicating the potential of HMA 8-m DEM for deriving the hydrological parameters.The results accrued in this investigation confirm that the HMA 8-m DEM has the best vertical accuracy and should be of high use for analyzing natural hazards and monitoring glacier surfaces. 展开更多
关键词 High Mountain Asia Digital elevation Model ICESat-2 geolocated photons Accuracy assessment
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Elevational patterns of warming effects on plant community and topsoil properties: focus on subalpine meadows ecosystem
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作者 HAO Aihua LUO Zhengming CHEN Xiaojiang 《Journal of Mountain Science》 SCIE CSCD 2024年第1期146-159,共14页
Climate warming profoundly affects plant biodiversity, community productivity, and soil properties in alpine and subalpine grassland ecosystems. However, these effects are poorly understood across elevational gradient... Climate warming profoundly affects plant biodiversity, community productivity, and soil properties in alpine and subalpine grassland ecosystems. However, these effects are poorly understood across elevational gradients in subalpine meadow ecosystems. To reveal the elevational patterns of warming effects on plant biodiversity, community structure, productivity, and soil properties, we conducted a warming experiment using open-top chambers from August 2019 to August 2022 at high(2764 m a. s. l.), medium(2631 m a. s. l.), and low(2544 m a. s. l.) elevational gradients on a subalpine meadow slope of Mount Wutai, Northern China. Our results showed that three years of warming significantly increased topsoil temperature but significantly decreased topsoil moisture at all elevations(P<0.05), and the percentage of increasing temperature and decreasing moisture both gradually raised with elevation lifting. Warming-induced decreasing proportions of soil organic carbon(SOC, by 19.24%), and total nitrogen(TN, by 24.56%) were the greatest at high elevational gradients. Experimental warming did not affect topsoil C: N, p H, NO_(3)^(-)-N, or NH_(4)^(+)-N at the three elevational gradients. Warming significantly increased species richness(P<0.01) and Shannon-Weiner index(P<0.05) at low elevational gradients but significantly decreased belowground biomass(P<0.05) at a depth of 0–10 cm at three elevational gradients. Warming caused significant increases in the aboveground biomass in the three elevational plots. Warming significantly increased the aboveground biomass of graminoids in medium(by 92.47%) and low(by 98.25%) elevational gradients, that of sedges in high(by 72.44%) and medium(by 57.16%) elevational plots, and that of forbs in high(by 75.88%), medium(by 34.38%), and low(by 74.95%) elevational plots. Species richness had significant linear correlations with SOC, TN, and C: N(P<0.05), but significant nonlinear responses to soil temperature and soil moisture in the warmed treatment(P<0.05). The warmed aboveground biomass had a significant nonlinear response to soil temperature and significant linear responses to soil moisture(P<0.05). This study provided evidence that altitude is a factor in sensitivity to climate warming, and these different parameters(e.g., plant species richness, Shannon-Weiner index, soil temperature, soil moisture, SOC, and TN) can be used to measure this sensitivity. 展开更多
关键词 Warming effect Plant diversity pattern Community structure change elevation gradient Alpine meadow ecosystem Mount Wutai
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No generality in biodiversity-productivity relationships along elevation in temperate and subtropical forest landscapes
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作者 Jiayun Zou Yahuang Luo +12 位作者 Rupert Seidl Dominik Thom Jie Liu Lisa Geres Tobias Richter Linjiang Ye Wei Zheng Liangliang Ma Jie Song Kun Xu Dezhu Li Lianming Gao Sebastian Seibold 《Forest Ecosystems》 SCIE CSCD 2024年第3期255-265,共11页
An improved understanding of biodiversity-productivity relationships(BPRs)along environmental gradients is crucial for effective ecosystem management and biodiversity conservation.The stress-gradient hypothesis sugges... An improved understanding of biodiversity-productivity relationships(BPRs)along environmental gradients is crucial for effective ecosystem management and biodiversity conservation.The stress-gradient hypothesis suggests that BPRs are stronger in stressful environments compared to more favorable conditions.However,there is limited knowledge regarding the variation of BPRs along elevational gradients and their generality across different landscapes.To study how BPRs change with elevation,we harnessed inventory data on 6,431 trees from152 plots surveyed twice in eight to ten year intervals in mountain forests of temperate Europe and subtropical Asia.We quantified the relationship between aboveground productivity and different biodiversity measures,including taxonomic,functional,and phylogenetic diversity.To elucidate the processes underlying BPRs,we studied the variation of different functional traits along elevation across landscapes.We found no general pattern of BPRs across landscapes and elevations.Relationships were neutral for all biodiversity measures in temperate forests,and negative for taxonomic and functional diversity in subtropical forests.BPRs were largely congruent between taxonomic,functional and phylogenetic diversity.We found only weak support for the stress-gradient hypothesis,with BPRs turning from negative to positive(effect not significant)close to the tree line in subtropical forests.In temperate forests,however,elevation patterns were strongly modulated by species identity effects as influenced by specific traits.The effect of traits such as community-weighted mean of maximum plant height and wood density on productivity was congruent across landscapes.Our study highlights the context-dependence of BPRs across elevation gradients and landscapes.Species traits are key modulating factors of BPRs and should be considered more explicitly in studies of the functional role of biodiversity.Furthermore,our findings highlight that potential trade-offs between conserving biodiversity and fostering ecosystem productivity exist,which require more attention in policy and management. 展开更多
关键词 Biodiversity-ecosystem functioning Climate mitigation elevation gradients Forest management Forest productivity Functional traits Nature conservation Phylogenetic diversity
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