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不同时间按压刺激对大鼠骨骼肌形态学及肿瘤坏死因子α、核因子κB的影响

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中国组织工程研究 2025年第17期29卷 3588-3595页

作者：石培丽林森赵文腾彭亚力胡亚哲华中师范大学体育学院湖北省武汉市430079 武汉体育学院体育科技学院湖北省武汉市430205

背景:研究发现不同时间长度按压点刺激正常肌肉,将产生不同的生理反应。目的:探讨在不同时间机械压力按压下,大鼠骨骼肌内炎性因子肿瘤坏死因子α及核因子κB表达的变化。方法:健康SPF级SD雄性大鼠20只,随机分为空白对照组、10 s按压组... 详细信息

背景:研究发现不同时间长度按压点刺激正常肌肉,将产生不同的生理反应。目的:探讨在不同时间机械压力按压下,大鼠骨骼肌内炎性因子肿瘤坏死因子α及核因子κB表达的变化。方法:健康SPF级SD雄性大鼠20只,随机分为空白对照组、10 s按压组、20 s按压组及30 s按压组,每只大鼠的单侧右腿用于实验。空白对照组不予干预,各按压组大鼠经2%戊巴比妥钠(35 mg/kg)腹腔注射麻醉后,使用自制机械压力装置,将压强固定在200 kPa,分别持续按压大鼠股薄肌10,20,30 s,随后即刻取右后肢按压处肌肉组织。苏木精-伊红染色观察骨骼肌组织形态学变化及肌纤维横截面积的变化,免疫组织化学检测骨骼肌肿瘤坏死因子α及核因子κB表达水平。结果与结论:①苏木精-伊红染色结果显示,各按压组大鼠骨骼肌肌纤维排列松散,肌纤维横截面积和直径变小,骨骼肌间隙变大。与空白对照组相比,各按压组骨骼肌肌纤维的横截面积显著减小(P0.05)。10 s按压组肌纤维间隙中未见明显红细胞,20 s按压组间隙中出现少量红细胞,30 s按压组骨骼肌肌纤维间毛细血管扩张,间隙中出现红细胞。②30 s按压组的骨骼肌肿瘤坏死因子α的表达水平显著高于空白对照组(P0.05)。④结果说明,压强固定在200 kPa时,骨骼肌经过按压会发生形态学变化,肌纤维横截面积减少,但按压10,20,30 s骨骼肌形态学及骨骼肌纤维横截面积无显著差异。随着时间点的变化,按压骨骼肌至30 s时,炎性因子肿瘤坏死因子α启动,但对核因子κB没有影响,推测短时间内炎性因子可出现表达,而转录因子未见明显变化。

关键词：骨骼肌炎性因子肿瘤坏死因子α 核因子κB 工程化细胞因子工程化组织构建

Agricultural Land Suitability of Production Space in the Taihang Mountains, China

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Chinese Geographical Science 2019年第6期29卷 1024-1038页

作者： GENG Shoubao shi peili ZONG Ning ZHU Wanrui Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China

The contradiction between the shortage of land for agriculture due to rapid expansion of industrialization and urbanization and increasing population pressure is projected to impose great threats to future food *** land suitability evaluation is an effective approach to improve the utilization of land resources for crop production and thus enhance the capacity of food *** this study, we evaluated the land suitability for agriculture of the production space in the Taihang Mountains by three steps: establishing indicator system, determining weights for indicators, and constructing a fuzzy matter-element model to assess the grades of *** showed that the land suitability had a significant linear correlation with potential crop yields, indicating our evaluation was effective to predict crop *** spatial pattern of land suitability for crop production demonstrated that land with higher suitability was generally located in piedmont plains and basins, while land with lower suitability was mostly situated in mountainous *** area of highly, moderately, marginally suitable and unsuitable land for agriculture was 32.13%, 28.58%, 37.49% and 1.80% of the production space, ***, the correlation degree analysis indicated that the requirements of these four suitability grades were currently not satisfied but could be potentially *** terms of indicator weights, soil properties were much more important than topography and location conditions to influence the grades of *** all indicators, slope, soil organic matter, soil texture and soil depth were the most influential factors, so slope farming prevention and organic fertilization were most likely to improve land suitability for *** the outputs of our land suitability evaluation model with the distribution of the existing croplands, we found that about 66.52% of marginally suitable and 54.55% of unsuitable land for agricul

关键词： agricultural land suitability matter-element model production space the Taihang Mountains

Effects of Grazing Exclusion on Plant Productivity and Soil Carbon, Nitrogen Storage in Alpine Meadows in Northern Tibet, China

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Chinese Geographical Science 2014年第4期24卷 488-498页

作者： XIONG Dingpeng shi peili SUN Yinliang WU Jianshuang ZHANG Xianzhou Lhasa National Ecological Research Station Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences University of Chinese Academy of Sciences

Grazing exclusion is widely adopted in restoring degraded alpine grasslands on the Qinghai-Tibetan Plateau. However, its effectiveness remains poorly understood. In this study, we investigated the effects of grazing exclusion on plant productivity, species diversity and soil organic carbon （SOC） and soil total nitrogen （STN） storage along a transect spanning from east to west of alpine meadows in northern Tibet, China. After six years of grazing exclusion, plant cover, aboveground biomass （AGB）, belowground biomass （BGB）, SOC and STN were increased, but species diversity indices declined. The enhancement of AGB and SOC caused by grazing exclusion was correlated positively with mean annual precipitation （MAP）. Grazing exclusion led to remarkable biomass increase of sedge species, especially Kobresia pygmaea, whereas decrease of biomass in forbs and no obvious change in grass, leguminous and noxious species. Root biomass was concentrated in the near surface layer （10 cm） after grazing exclusion. The effects of grazing exclusion on SOC storage were confined to shallow soil layer in sites with lower MAP. It is indicated that grazing exclusion is an effective measure to increase forage production and enhance soil carbon sequestration in the studied region. The effect is more efficient in sites with higher precipitation. However, the results revealed a tradeoff between vegetation restoration and ecological biodiversity. Therefore, carbon pools recover more quickly than plant biodiversity in the alpine meadows. We suggest that grazing exclusion should be combined with other measures to reconcile grassland restoration and biodiversitv conservation.

关键词： aboveground biomass belowground biomass soil organic carbon (SOC) soil total nitrogen (STN) biodiversity grazingexclusion precipitation alpine meadow

Effects of livestock exclusion and climate change on aboveground biomass accumulation in alpine pastures across the Northern Tibetan Plateau

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Chinese Science Bulletin 2014年第32期59卷 4332-4340页

作者： Jianshuang Wu Xianzhou Zhang Zhenxi Shen peili shi Chengqun Yu Baoxiong Chen Lhasa Plateau Ecosystem Research Station Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences University of Chinese Academy of Sciences

To better understand the ecological and economic benefits of short-term grazing exclusion on the aboveground net primary productivity(ANPP)of alpine pastures,we conducted annual multi-site transect surveys in the summers from 2009 to 2011 and calculated the aboveground biomass discrepancy(ABD)between grazed and ungrazed pastures at plant community and economic group levels for three zonal alpine grassland types—meadow,steppe,and desert-steppe—across the northern Tibetan *** results indicated that aboveground biomass(AGB)significantly differed among grassland types and declined northwesterly from 64.07 to11.44 g m-2with decreasing precipitation and increasing *** mean ABD exhibited considerable community dependency,with meadow(12.47 g m-2)[steppe(6.91 g m-2)[desert steppe(2.54 g m-2),and it declined from 25.42 to 1.29 g m-2with decreasing precipitation and increasing temperature.‘Good forage’,*** and sedges,benefited most from grazing exclusion,followed by edible *** longer grazing exclusion durations(GEDs),the aboveground biomass of poisonous locoweeds initially decreased and then increased compared with the adjacent grazed *** the nested analysis of co-variances with a general linear model,growing season precipitation(GSP;from May to September)accounted for 52.67%ofthe observed variation in AGB,followed by AGT(9.77%)and pasture management systems(PMSs;grazing or grazing-excluded,5.31%).The variation in ABD was explained primarily by AGT(16.52%),GED(20.25%),and the interaction of AGT 9 GED(19.58%).Our results confirm that precipitation is the primary factor controlling the ANPP of alpine grasslands on the Northern Tibetan Plateau and that the ecological benefits arising from grazing exclusion are also partly dependent on grassland type and exclusion ***,spatial and temporal variations in growing season precipitation and plant functional traits or economic group composition should be jointly considered when devel

关键词：地上生物量藏北高原生物量积累牧场高山气候变化荒漠草原牲畜

Impact of Cloud on Net Ecosystem CO_(2) Exchange of Alpine Meadow in Tibetan Plateau

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Chinese Journal of Population,Resources and Environment 2010年第4期8卷 69-75页

作者： Fan Yuzhi Zhang Xianzhou shi peili Wu Jianshuang Institute of Geographic Sciences and Resources Research Chinese Academy of SciencesBeijing 100101China Graduate University of Chinese Academy of Sciences Beijing 100049China

Meteorological elements and CO_(2) fluxes over alpine meadow ecosystem were observed continuously from 2004 to 2005 in Damxung Alpine Meadow Flux Station,China Flux *** on the eddy covariance CO_(2) fluxes and meteorological data obtained,the relationships among the CO_(2) fluxes,the cloud amount,and the meteorological factors in alpine meadow ecosystem were explored and *** conclusions can be drawn from the discussion with previous researches as following:(1)the cloud amount can affect the net ecosystem CO_(2) exchange(NEE)of alpine meadow on Tibetan Plateau;(2)the soil temperature sensitive to the cloud amount,is a major environmental controlling factor for NEE,and closely relates to the maximum of *** the moming period with large cloud amount,the NEE reaches its maximum when the clearness index ranges from 0.5 to 0.7;yet in the afternoon it comes to the maximum with the index from 0.2 to *** span of soil temperature covers from 12 to 15℃as the NEE at its highest;(3)the scatterplots between NEE and photosynthetic available radiation(PAR)was a significant inverse triangle in the clear day,two different kinds of concave curves in the cloudy day,and strongly convergent rectangular hyperbola in the overcast *** differences were controlled by the changes of light radiation and soil temperature.

关键词： net ecosystem CO_(2)exchange cloud amount clearness index alpine meadow ecosystem Tibetan Plateau

Characteristics of net ecosystem carbon dioxide exchange(NEE)from August to October of Alpine meadow on the Tibetan Plateau,China

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Frontiers in Biology 2006年第4期1卷 418-422页

作者： XU Lingling ZHANG Xianzhou shi peili YU Guirui SUN Xiaomin Institute of Geographical Sciences and Natural Resources Research Beijing 100101China Graduate School of Chinese Academy of Sciences Beijing 100039China

The Alpine meadow is one of the vegetation types widely distributed on the Tibetan Plateau in China with an area of about 1.2 million square *** Damxung rangeland station,located in the hinterland of the Tibetan Plateau,is covered with an typical *** continuous carbon flux data(from August to middle October,2003)measured with the open-path eddy covariance system was used to analyze the diurnal variation pattern of net ecosystem carbon dioxide exchange(NEE)and its relationship with the environmental factors,such as photosynthetically active radiation(PAR),precipitation,and *** showed that NEE presented obvious diurnal variation pattern with single-peak of diurnal maximum carbon assimilation at 11:00^(−1)2:00(local time)with an average of-0.268 mg CO_(2)⋅m^(−2)⋅s^(−1),i.e.,-6.08μmol CO_(2)⋅m^(−2)⋅s^(−1).During the daytime,NEE fitted fairly well with PAR in a rectangular hyperbola function with the apparent quantum yield(0.0203μmol CO_(2)μmol^(−1)PAR)and maximum ecosystem assimilation(9.7411μmol CO_(2)⋅m^(−2)⋅s^(−1)).During the night-time,NEE showed a good exponential relation with the soil temperature at 5 cm depth.

关键词： Tibetan Plateau in China Alpine meadow eddy covariance carbon flux environmental factors

Changes in individual plant traits and biomass allocation in alpine meadow with elevation variation on the Qinghai-Tibetan Plateau

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Science China(Life Sciences) 2010年第9期53卷 1142-1151页

作者： MA WeiLing shi peili LI WenHua HE YongTao ZHANG XianZhou SHEN ZhenXi CHAI SiYue Lhasa National Ecological Research Station Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Graduate University of Chinese Academy of Sciences Beijing 100049China

Plant traits and individual plant biomass allocation of 57 perennial herbaceous species,belonging to three common functional groups (forbs,grasses and sedges) at subalpine (3700 m ASL),alpine (4300 m ASL) and subnival (≥5000 m ASL) sites were examined to test the hypothesis that at high altitudes,plants reduce the proportion of aboveground parts and allocate more biomass to belowground parts,especially storage organs,as altitude increases,so as to geminate and resist environmental ***,results indicate that some divergence in biomass allocation exists among *** increasing altitude,the mean fractions of total biomass allocated to aboveground parts *** mean fractions of total biomass allocation to storage organs at the subalpine site (7%±2% S.E.) were distinct from those at the alpine (23%±6%) and subnival (21%±6%) sites,while the proportions of green leaves at all altitudes remained almost *** 4300 m and 5000 m,the mean fractions of flower stems decreased by 45% and 41%,respectively,while fine roots increased by 86% and 102%,*** leaf areas and leaf areas of forbs and grasses deceased with rising elevation,while sedges showed opposite *** all three functional groups,leaf area ratio and leaf area root mass ratio decreased,while fine root biomass increased at higher *** allocation patterns of alpine plants were characterized by a reduction in aboveground reproductive organs and enlargement of fine roots,while the proportion of leaves remained *** was beneficial for high altitude plants to compensate carbon gain and nutrient uptake under low temperature and limited nutrients by stabilizing biomass investment to photosynthetic structures and increasing the absorption surface area of fine *** contrast to forbs and grasses that had high mycorrhizal infection,sedges had higher single leaf area and more root fraction,especially fine roots.

关键词： Qinghai-Tibetan Plateau climate stress biomass allocation shoot/root ratio plant traits fine roots

High-altitude tree growth responses to climate change across the Hindu Kush Himalaya

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Journal of Plant Ecology 2021年第5期14卷 829-842页

作者： Lili Zheng Narayan Prasad Gaire peili shi Lhasa Plateau Ecosystem Research Station Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100190China CAS Key Laboratory of Tropical Forest Ecology Xishuanghanna Tropical Botanical GardenChinese Academy of SciencesMenglunMenglaYunnan 666303China Central Department of Environmental Science Tribhuvan UniversityKirtipurKathniantluNepal

Aims Rapid warming at high altitudes may lead to a higher sensitivity in tree growth to *** key factors constraining tree radial growth and to what extent regional tree growth has suffered from climatic changes are *** Tree-ring width data were collected from 73 sites across the Hindu Kush Himalaya(HKH),including three dominant genera(Abies,Juniperus and Picea)at high altitudes over 3000 *** time warping was introduced to develop subregional chronologies by considering the synchrony of annual tree growth among different *** quantified the contribution of the climate variables,and analyzed the spatiotemporal variation of the growth–climate *** Findings The site chronologies were grouped into three clusters,corresponding to the three distinct bioclimatic zones,*** western HKH,central-eastern HKH and southeastern Tibetan Plateau(TP).Tree growth was positively correlated to winter and spring precipitation in the drier western HKH,and to winter temperature and spring precipitation in the humid southeastern *** growth was markedly constrained by the minimum temperature,especially in winter,with its importance increasing from the west toward the *** shown by moving correlation analysis,the signal of winter temperature in tree growth was weakened in the western and central-eastern HKH,while it was enhanced in the southeastern TP following rapid warming since the *** results highlight that continuous warming may cause forest recession due to warming-induced moisture deficit in the western HKH,but forest expansion in the southeastern TP.

关键词： tree ring high-altitude forests key climate factors tree growth-climate relationships growth trends climate sensitivity

The relative controls of temperature and soil moisture on the start of carbon flux phenology and net ecosystem production in two alpine meadows on the Qinghai-Tibetan Plateau

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Journal of Plant Ecology 2020年第2期13卷 247-255页

作者： Xi Chai peili shi Minghua Song Ning Zong Yongtao He Yingnian Li Xianzhou Zhang Yanjiao Liu Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Science11ADatun RoadChaoyang DistrictBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesNo.80 Zhongguancun East RoadHaidian DistrictBeijing 100190China Northwest Institute of Plateau Biology Chinese Academy of SciencesNo.23 Xinning roadXiningQinghai Province 810008China Beijing Zhongnong Futong Horticulture Co. Ltd.No.17 Qinghua East RoadHaidian DistrictBeijing 100083China

Aims Variations in vegetation spring phenology are widely attributed to temperature in temperate and cold ***,temperature effect on phenology remains elusive in cold and arid/semiarid ecosystems because soil water condition also plays an important role in mediating *** We used growing degree day(GDD)model and growing season index(GSI)model,coupling minimum temperature(T_(min))with soil moisture(SM)to explore the influence of heat requirement and hydroclimatic interaction on the start of carbon uptake period(SCUP)and net ecosystem productivity(NEP)in two alpine meadows with different precipitation regimes on the Qinghai-Tibet Plateau(QTP).One is the water-limited alpine steppe-meadow,and the other is the temperature-limited alpine *** Findings We observed two clear patterns linking GDD and GSI to SCUP:SCUP was similarly sensitive to variations in preseason GDD and GSI in the humid alpine shrub-meadow,while SCUP was more sensitive to the variability in preseason GSI than GDD in the semiarid alpine *** divergent patterns indicated a balance of the limiting climatic factors between temperature and water *** the humid meadow,higher temperature sensitivity of SCUP could maximize thermal benefit without drought stress,as evidenced by the stronger linear correlation coefficient(R2)and Akaike’s information criterion(AIC)between observed SCUPs and those of simulated by GDD ***,greater water sensitivity of SCUP could maximize the benefit of water in semiarid steppe-meadow,which is indicated by the stronger R2 and AIC between observed SCUPs and those of simulated by GSI ***,although SCUPs were determined by GDD in the alpine shrub-meadow ecosystem,NEP was both controlled by accumulative GSI in two alpine *** study highlights the impacts of hydroclimatic interaction on spring carbon flux phenology and vegetation productivity in the humid and semiarid alpine *** resu

关键词： growing degree day growing season index the start of carbon uptake period net ecosystem production alpine meadows Qinghai-Tibet Plateau