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Expansion and Declination--An Analysis of Power's Ecological Thoughts in Gain 被引量:2
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作者 梁渊 陈益 《海外英语》 2018年第9期173-174,176,共3页
This paper attempts to interpret Richard Powers' ecological thoughts in his sixth novel Gain. It mainly records the development of the corporate body's expansion and the individual body's declination to fu... This paper attempts to interpret Richard Powers' ecological thoughts in his sixth novel Gain. It mainly records the development of the corporate body's expansion and the individual body's declination to further analyze how the corporate organism becomes a lethal threat to the individual in the end. The two narrative lines reveals the worsening of industrial greedy and the increasing danger of human existence.Powers expresses his holistic ecological vision: Are big companies human's greatest hope or greatest threat? 展开更多
关键词 GAIN EXPANSION declination Ecological Thoughts
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Changes in Endopeptidase Activity during Photosynthetic Declination in Rice Leaf
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作者 DENGZhi-rui ZHANGRong-xian 《Rice science》 SCIE 2004年第3期120-124,共5页
Two japonica rice varieties, Wuyujing 3 and 97-7, were used to study the changes in contents of soluble protein, free amino acids and endopeptidase activity during photosynthetic declination. The content of soluble pr... Two japonica rice varieties, Wuyujing 3 and 97-7, were used to study the changes in contents of soluble protein, free amino acids and endopeptidase activity during photosynthetic declination. The content of soluble protein in flag leaf of cv. Wuyujing 3 was higher than that of cv. 97-7, but decreased rapidly in Wuyujing 3. Free amino acids in flag leaf and the thirteenth leaf of Wuyujing 3 started to increase 10 days before the turning point of photosynthetic declination (TPPD), while it occurred just 1-2 days before TPPD in the flag leaf and the thirteenth leaf of 97-7. During reversible phase of photosynthetic declination, endopeptidase activity remained at a low level and increased slightly only in the later part of this phase. Then it rose up rapidly at irreversible decline phase and reached a very high level. For Wuyujing 3, the change in endopeptidase activity in the thirteenth leaf was parallel to that in flag leaf. However, for 97-7, the rapid increase of endopeptidase activity in the thirteenth leaf started later than that of flag leaf. The results implied that the rate of protein breakdown and conversion to transportable nitrogen in leaves of 97-7 was slower than that in leaves of Wuyujing 3 during photosynthetic declination and it led to relatively lower seed setting rate and fully filling grains rate in 97-7. This may be one of the important reasons why 97-7 could not bring the high yield potentiality into play and the findings may be taken into consideration while breeding for high potential varieties in future. 展开更多
关键词 RICE photosyntheric declination soluble protein free amino acids endopeptidase activity
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The rate of deadwood decomposition processes in tree stand gaps resulting from bark beetle infestation spots in mountain forests
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作者 Ewa Błonska Adam Gorski Jarosław Lasota 《Forest Ecosystems》 SCIE CSCD 2024年第3期339-346,共8页
Decaying wood is an essential element of forest ecosystems and it affects its other components.The aim of our research was to determine the decomposition rate of deadwood in various humidity and thermal conditions in ... Decaying wood is an essential element of forest ecosystems and it affects its other components.The aim of our research was to determine the decomposition rate of deadwood in various humidity and thermal conditions in the gaps formed in the montane forest stands.The research was carried out in the Babiog orski National Park.The research plots were marked out in the gaps of the stands,which were formed as a result of bark beetle gradation.Control plots were located in undisturbed stands.The research covered wood of two species–spruce and beech in the form of cubes with dimensions of 50 mm×50 mm×22 mm.Wood samples were placed directly on the soil surface and subjected to laboratory analysis after 36 months.A significant influence of the wood species and the study plot type on the physicochemical properties of the tested wood samples was found.Wood characteristics strongly correlated with soil moisture.A significantly higher mass decline of wood samples was recorded on the reference study plots,which were characterized by more stable moisture conditions.Poorer decomposition of wood in the gaps regardless of the species is related to lower moisture.The wood species covered by the study differed in the decomposition rate.Spruce wood samples were characterized by a significantly higher decomposition rate compared to beech wood samples.Our research has confirmed that disturbances that lead to the formation of gaps have a direct impact on the decomposition process of deadwood. 展开更多
关键词 Bark beetle BEECH Decomposition rate Forest ecosystem Mass decline SPRUCE Woody debris
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Neuroprotective effects of G9a inhibition through modulation of peroxisome-proliferator activator receptor gamma-dependent pathways by miR-128
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作者 Aina Bellver-Sanchis Pedro AAvila-López +9 位作者 Iva Tic David Valle-García Marta Ribalta-Vilella Luis Labrador Deb Ranjan Banerjee Ana Guerrero Gemma Casadesus Coralie Poulard Mercè Pallàs Christian Grinán-Ferré 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第11期2532-2542,共11页
Dysregulation of G9a,a histone-lysine N-methyltransferase,has been observed in Alzheimer’s disease and has been correlated with increased levels of chronic inflammation and oxidative stress.Likewise,microRNAs are inv... Dysregulation of G9a,a histone-lysine N-methyltransferase,has been observed in Alzheimer’s disease and has been correlated with increased levels of chronic inflammation and oxidative stress.Likewise,microRNAs are involved in many biological processes and diseases playing a key role in pathogenesis,especially in multifactorial diseases such as Alzheimer’s disease.Therefore,our aim has been to provide partial insights into the interconnection between G9a,microRNAs,oxidative stress,and neuroinflammation.To better understand the biology of G9a,we compared the global microRNA expression between senescence-accelerated mouse-prone 8(SAMP8)control mice and SAMP8 treated with G9a inhibitor UNC0642.We found a downregulation of miR-128 after a G9a inhibition treatment,which interestingly binds to the 3′untranslated region(3′-UTR)of peroxisome-proliferator activator receptor γ(PPARG)mRNA.Accordingly,Pparg gene expression levels were higher in the SAMP8 group treated with G9a inhibitor than in the SAMP8 control group.We also observed modulation of oxidative stress responses might be mainly driven Pparg after G9a inhibitor.To confirm these antioxidant effects,we treated primary neuron cell cultures with hydrogen peroxide as an oxidative insult.In this setting,treatment with G9a inhibitor increases both cell survival and antioxidant enzymes.Moreover,up-regulation of PPARγby G9a inhibitor could also increase the expression of genes involved in DNA damage responses and apoptosis.In addition,we also described that the PPARγ/AMPK axis partially explains the regulation of autophagy markers expression.Finally,PPARγ/GADD45αpotentially contributes to enhancing synaptic plasticity and neurogenesis after G9a inhibition.Altogether,we propose that pharmacological inhibition of G9a leads to a neuroprotective effect that could be due,at least in part,by the modulation of PPARγ-dependent pathways by miR-128. 展开更多
关键词 aging cognitive decline epigenetics G9a inhibition microRNAs miR-128 peroxisome-proliferator activator receptorγ(PPARγ) PPARG SAMP8
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Gut microbiota-astrocyte axis: new insights into age-related cognitive decline
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作者 Lan Zhang Jingge Wei +5 位作者 Xilei Liu Dai Li Xiaoqi Pang Fanglian Chen Hailong Cao Ping Lei 《Neural Regeneration Research》 SCIE CAS 2025年第4期990-1008,共19页
With the rapidly aging human population,age-related cognitive decline and dementia are becoming increasingly prevalent worldwide.Aging is considered the main risk factor for cognitive decline and acts through alterati... With the rapidly aging human population,age-related cognitive decline and dementia are becoming increasingly prevalent worldwide.Aging is considered the main risk factor for cognitive decline and acts through alterations in the composition of the gut microbiota,microbial metabolites,and the functions of astrocytes.The microbiota–gut–brain axis has been the focus of multiple studies and is closely associated with cognitive function.This article provides a comprehensive review of the specific changes that occur in the composition of the gut microbiota and microbial metabolites in older individuals and discusses how the aging of astrocytes and reactive astrocytosis are closely related to age-related cognitive decline and neurodegenerative diseases.This article also summarizes the gut microbiota components that affect astrocyte function,mainly through the vagus nerve,immune responses,circadian rhythms,and microbial metabolites.Finally,this article summarizes the mechanism by which the gut microbiota–astrocyte axis plays a role in Alzheimer’s and Parkinson’s diseases.Our findings have revealed the critical role of the microbiota–astrocyte axis in age-related cognitive decline,aiding in a deeper understanding of potential gut microbiome-based adjuvant therapy strategies for this condition. 展开更多
关键词 age aging Alzheimer’s disease ASTROCYTES cognitive decline DEMENTIA gut microbiota gut–brain axis microbial metabolites NEUROINFLAMMATION Parkinson’s disease
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Industrial-scale investigations on effects of tertiary-air declination angle on combustion and steam temperature characteristics in a 350-MW supercritical down-fired boiler
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作者 Xiaoguang LI Lingyan ZENG +8 位作者 Hongye LIU Yao LI Yifu LI Yunlong ZHAO Bo JIAO Minhang SONG Shaofeng ZHANG Zhichao CHEN Zhengqi LI 《Frontiers in Energy》 SCIE CSCD 2021年第1期132-142,共11页
Industrial-scale experiments were conducted to study the effects of tertiary air declination angle(TDA)on the coal combustion and steam temperature characteristics in the first 350-MW supercritical down-fired boiler i... Industrial-scale experiments were conducted to study the effects of tertiary air declination angle(TDA)on the coal combustion and steam temperature characteristics in the first 350-MW supercritical down-fired boiler in China with the multiple-injection and multiple-staging combustion(MIMSC)technology at medium and high loads.The experimental results indicated that as the TDA increased from 0°to 15°,the overall gas temperature in the lower furnace rose and the symmetry of temperature field was enhanced.The ignition distance of the fuel-rich coal/air flow decreased.In near-burner region,the concentration of O2 decreased while the concentrations of CO and NO increased.The concentration of NO decreased in near-tertiary-air region.The carbon in fly ash decreased significantly from 8.40%to 6.45%at a load of 260 MW.At a TDA of 15°,the ignition distances were the shortest(2.07 m and 1.73 m)at a load of 210 MW and 260 MW,respectively.The main and reheat steam temperatures were the highest(557.2℃ and 559.4℃ at a load of 210 MW,558.4℃ and 560.3℃ at a load of 260 MW).The carbon in fly ash was the lowest(4.83%)at a load of 210 MW.On changing the TDA from 15°to 25°,the flame kernel was found to move downward and the main and reheat steam temperatures dropped obviously.The change of TDA has little effect on NO_(x) emissions(660–681 mg/m^(3) at 6%O_(2)).In comprehensive consideration of the pulverized coal combustion characteristics and the unit economic performance,an optimal TDA of 15°is recommended. 展开更多
关键词 supercritical down-fired boiler industrialscale experiment tertiary air declination angle coal combustion steamtemperature
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Measuring magnetic declination with a compass, virtual globes and a global positioning system
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作者 William P.O’Brien Jr 《International Journal of Digital Earth》 SCIE 2009年第1期31-43,共13页
Earth’s magnetic declination was experimentally measured at 15 sites in western USA from Alaska to Texas;each site exhibited a large linear feature identifiable in virtual globe imagery(NASA’s World Wind or Google E... Earth’s magnetic declination was experimentally measured at 15 sites in western USA from Alaska to Texas;each site exhibited a large linear feature identifiable in virtual globe imagery(NASA’s World Wind or Google Earth).The difference between the geographic bearing of the linear feature measured directly on a virtual globe image and the magnetic bearing of the same linear feature measured on the ground with a compass defines the magnetic declination d for that site.For all 15 sites,d values,determined by this differencing procedure,ranged from about 208 to 58 E and fell within 18(over half within 0.58)of expected values.Global positioning system(GPS)data recorded at most sites and plotted on virtual globe images aided in the identification of relevant features.This straightforward method for determining magnetic declination using virtual globe software and a compass provides a contemporary geospatial field/laboratory activity that dramatically elucidates and contrasts features of magnetic and geographic coordinate systems for students in various disciplines involving geomagnetism,navigation,geography or spherical polar geometry. 展开更多
关键词 Earth observation GPS magnetic declination GEOPHYSICS
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Does pollinator dependence decrease along elevational gradients? 被引量:1
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作者 Yue-Wen Xu Lu Sun +3 位作者 Rong Ma Yong-Qian Gao Hang Sun Bo Song 《Plant Diversity》 SCIE CAS CSCD 2023年第4期446-455,共10页
Plants have long been thought to be less dependent on pollinators for seed production at higher elevations due to adverse pollination environments.However,recent research has yet to consistently support the generality... Plants have long been thought to be less dependent on pollinators for seed production at higher elevations due to adverse pollination environments.However,recent research has yet to consistently support the generality of this expectation.In this study,we asked whether pollinator dependence decreases along an elevational gradient and how it varies with various reproductive traits.To answer these questions,we quantified pollinator-plant associations and various reproductive traits for 112 flowering plants spanning a large elevational gradient(990-4260 m a.s.l.)in the Qinghai-Tibet Plateau.We found that flowering plants in the Qinghai-Tibet Plateau region are highly dependent on pollinators for seed production(76.2%of seed production was contributed by animal pollinators and 44.6%of plants would produce no seed without pollinator visitation).Contrary to our expectation,there was no significant elevational gradient in pollinator dependence index.Although the pollinator dependence index was not significantly correlated with pollen limitation,flower size,floral longevity,or reward type,it was correlated with compatibility status and flowering time.These findings indicate that pollinator dependence does not decrease along an elevational gradient in the Qinghai-Tibet Plateau.Our study also highlights the severe vulnerability of flowering plant seed production to pollinator declines under global change in the Qinghai-Tibet Plateau region,particularly for early-flowering or self-incompatible plants growing at higher elevations(e.g.,subnival belt). 展开更多
关键词 Global change Pollen limitation Pollinator decline Qinghai-Tibet plateau Seed production
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Shale oil enrichment evaluation and production law in Gulong Sag,Songliao Basin,NE China 被引量:2
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作者 SUN Longde CUI Baowen +9 位作者 ZHU Rukai WANG Rui FENG Zihui LI Binhui ZHANG Jingya GAO Bo WANG Qingzhen ZENG Huasen LIAO Yuanhui JIANG Hangl 《Petroleum Exploration and Development》 SCIE 2023年第3期505-519,共15页
Based on the results of drilling,tests and simulation experiments,the shales of the Cretaceous Qingshankou Formation in the Gulong Sag of the Songliao Basin are discussed with respect to hydrocarbon generation evoluti... Based on the results of drilling,tests and simulation experiments,the shales of the Cretaceous Qingshankou Formation in the Gulong Sag of the Songliao Basin are discussed with respect to hydrocarbon generation evolution,shale oil occurrence,and pore/fracture evolution mechanism.In conjunction with a substantial amount of oil testing and production data,the Gulong shale oil enrichment layers are evaluated and the production behaviors and decline law are analyzed.The results are drawn in four aspects.First,the Gulong shales are in the stage of extensive hydrocarbon expulsion when R_(0) is 1.0%-1.2%,with the peak hydrocarbon expulsion efficiency of 49.5%approximately.In the low-medium maturity stage,shale oil migrates from kerogen to rocks and organic pores/fractures.In the medium-high maturity stage,shale oil transforms from adsorbed state to free state.Second,the clay mineral intergranular pores/fractures,dissolution pores,and organic pores make up the majority of the pore structure.During the transformation,clay minerals undergo significant intergranular pore/fracture development between the minerals such as illite and illite/smectite mixed layer.A network of pores/fractures is formed by organic matter cracking.Third,free hydrocarbon content,effective porosity,total porosity,and brittle mineral content are the core indicators for the evaluation of shale oil enrichment layers.Class-I layers are defined as free hydrocarbon content equal or greater than 6.0 mg/g,effective porosity equal or greater than 3.5%,total porosity equal or greater than 8.0%,and brittle mineral content equal or greater than 50%.It is believed that the favourable oil layers are Q2-Q3 and Q8-Q9.Fourth,the horizontal wells in the core area of the light oil zone exhibit a high cumulative production in the first year,and present a hyperbolic production decline pattern,with the decline index of 0.85-0.95,the first-year decline rate of 14.5%-26.5%,and the single-well estimated ultimate recovery(EUR)greater than 2.0×10^(4)t.In practical exploration and production,more efforts will be devoted to the clarification of hydrocarbon generation and expulsion mechanisms,accurate testing of porosity and hydrocarbon content/phase of shale under formation conditions,precise delineation of the boundary of enrichment area,relationship between mechanical properties and stimulated reservoir volume,and enhanced oil recovery,in order to improve the EUR and achieve a large-scale,efficient development of shale oil. 展开更多
关键词 Songliao Basin Gulong shale oil Cretaceous Qingshankou Formation hydrocarbon generation and expulsion reservoir pore type pore/fracture formation mechanism enrichment layer evaluation production decline law
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Efficacy of prednisone combined with mycophenolate mofetil for immunoglobulin A nephropathy with moderate-to-severe renal dysfunction 被引量:1
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作者 Mei-Juan Meng Ling Hu +5 位作者 Yun Fan Han Gao Han-Zhi Chen Cai-Mei Chen Zhen Qi Bin Liu 《World Journal of Clinical Cases》 SCIE 2023年第35期8300-8309,共10页
BACKGROUND Immunoglobulin A nephropathy(IgAN)is a common form of chronic glomer-ulonephritis.Currently,IgAN is one of the main causes of chronic renal failure in China;its prognosis varies greatly between patients,wit... BACKGROUND Immunoglobulin A nephropathy(IgAN)is a common form of chronic glomer-ulonephritis.Currently,IgAN is one of the main causes of chronic renal failure in China;its prognosis varies greatly between patients,with renal function at the time of diagnosis and prognosis being strongly correlated.Mycophenolate mofetil(MMF)is a drug with a good immunomodulatory effect and is commonly used clinically.However,its effects in IgAN have not yet been clearly demonstrated.Therefore,herein,we retrospectively compared the effectiveness and safety of prednisone alone or combined with MMF for the treatment of primary IgAN with moderate-to-severe renal impairment.METHODS Between January 2011 and December 2020,200 patients with moderate-to-severe IgAN were included in this study,all of whom were admitted to Wuxi People's Hospital affiliated with Nanjing Medical University.All patients underwent a renal puncture biopsy,which revealed primary IgAN with a glomerular filtration rate(GFR)of 30–60 mL/min.The patients were divided into a glucocorticoid therapy group(GTG)and an immunosuppressive therapy group(ITG)according to the different treatment regimens,with 100 patients in each group.Based on general treatments,such as angiotensin-converting enzyme inhibitors/angiotensin receptor blockers,patients in the GTG were administered prednisone 0.5–0.8 mg/(kg·d^(-1))for 4–8 wk,which was reduced by 5 mg every two weeks until the maintenance(30 mg/d)dose was reached and maintained for 12 mo.In the ITG,MMF was administered at 1.0 g/d for 6–12 mo,followed by a maintenance dosage of 0.5 g/d for 12 mo.Age,sex,blood pressure,24-h urinary egg white measurement,serum creatinine(Scr),blood uric acid,blood albumin,blood potassium(K),hemoglobin,GFR,alanine aminotransferase,total cholesterol(T-CHO),fasting blood glucose,and body mass index were recorded.The 24-h urinary protein,Scr,and GFR levels were recorded 3,6,9,and 12 mo after treatment.Follow-up data were also collected.RESULTS No discernible differences existed between the two groups in terms of age,sex,blood pressure,creatinine,24-h urinary protein level,GFR,or other biochemical indicators at the time of enrollment.Both regimens significantly reduced the 24-h urinary protein quantitation and stabilized renal function.Nine months after treatment,the 24-h urinary protein and Scr of the ITG decreased more significantly than those of the GTG.By the 12th month of treatment,the 24-h urinary protein and Scr in both groups continued to decrease compared to those by the 9th month.In addition,the overall response rate in the ITG was significantly higher than that in the GTG.The occurrence of side effects did not vary significantly between the two regimens;however,endpoint events were significantly more common in the GTG than in the ITG.The follow-up time for the GTG was noticeably lower than that for the ITG.CONCLUSION Prednisone combined with MMF was effective for the treatment of IgAN with moderate-to-severe renal dysfunction. 展开更多
关键词 IGAN Moderate-to-severe decline in renal function PREDNISONE MYCOPHENOLATE Treatment effect Safety
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Reasons and effects of the decline of willing related potential living kidney donors 被引量:1
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作者 Rabea Ahmed Gadelkareem Amr Mostafa Abdelgawad +5 位作者 Nasreldin Mohammed Ahmed Reda Nashwa Mostafa Azoz Mohammed Ali Zarzour Hisham Mokhtar Hammouda Mahmoud Khalil 《World Journal of Transplantation》 2023年第5期276-289,共14页
BACKGROUND Although the availability of related living donors(LDs)provides a better chance for receiving kidney transplantation(KT),the evaluation protocols for LD selection remain a safeguard for the LD’s safety.The... BACKGROUND Although the availability of related living donors(LDs)provides a better chance for receiving kidney transplantation(KT),the evaluation protocols for LD selection remain a safeguard for the LD’s safety.These protocols are variable from one center to another,resulting in variable rates of decline of the potential LDs(PLDs).The decline of willing PLDs may occur at any stage of evaluation,starting from the initial contact and counseling to the day of operation.AIM To identify the causes of the decline of PLDs,the predictors of PLD candidacy,and the effect on achieving LDKT.METHODS A retrospective study was performed on the willing PLDs who attended our outpatient clinic for kidney donation to their related potential recipients between October 2015 and December 2022.The variables influencing their candidacy rate and the fate of their potential recipients were studied.Two groups of PLDs were compared:Candidate PLDs after a completed evaluation vs non-candidate PLDs with a complete or incomplete evaluation.A multivariate logistic regression was performed to assess the factors contributing to the achievement of PLD candidacy.RESULTS Of 321 willing PLDs,257 PLDs(80.1%)accessed the evaluation to variable extents for 212 potential recipients,with a mean age(range)of 40.5±10.4(18-65)years,including 169 females(65.8%).The remaining 64 PLDs(19.9%)did not access the evaluation.Only 58 PLDs(18.1%)succeeded in donating,but 199 PDLs(62.0%)were declined;exclusion occurred in 144 PLDs(56.0%)for immunological causes(37.5%),medical causes(54.9%),combined causes(9.7%),and financial causes(2.1%).Regression and release occurred in 55 PLDs(17.1%).The potential recipients with candidate PLDs were not significantly different from those with non-candidate PLDs,except in age(P=0.041),rates of completed evaluation,and exclusion of PLDs(P<0.001).There were no factors that independently influenced the rate of PLD candidacy.Most patients who failed to have KT after the decline of their PLDs remained on hemodialysis for 6 mo to 6 years.CONCLUSION The rate of decline of willing related PLDs was high due to medical or immunological contraindications,release,or regression of PLDs.It reduced the chances of high percentages of potential recipients in LDKT. 展开更多
关键词 Donor decline Donor evaluation Donor exclusion Kidney transplantation Living kidney donors Related living donors
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Alzheimer’s disease risk after COVID-19:a view from the perspective of the infectious hypothesis of neurodegeneration
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作者 Eugenia Olivera Albany Sáez +3 位作者 Lila Carniglia Carla Caruso Mercedes Lasaga Daniela Durand 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第7期1404-1410,共7页
In light of the rising evidence of the association between viral and bacterial infections and neurodegeneration,we aimed at revisiting the infectious hypothesis of Alzheimer’s disease and analyzing the possible impli... In light of the rising evidence of the association between viral and bacterial infections and neurodegeneration,we aimed at revisiting the infectious hypothesis of Alzheimer’s disease and analyzing the possible implications of COVID-19 neurological sequelae in long-term neurodegeneration.We wondered how SARS-CoV-2 could be related to the amyloid-βcascade and how it could lead to the pathological hallmarks of the disease.We also predict a paradigm change in clinical medicine,which now has a great opportunity to conduct prospective surveillance of cognitive sequelae and progression to dementia in people who suffered severe infections together with other risk factors for Alzheimer’s disease. 展开更多
关键词 Alzheimer amyloid beta antimicrobial cognitive decline COVID-19 infectious hypothesis long-term sequelae NEURODEGENERATION NEUROINFLAMMATION neurological symptoms NEUROTROPISM SARS-CoV-2
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Association Between Constipation and a Reduction in Lower Limb Muscle Strength in Preoperative Patients with Thoracic Spinal Tumors
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作者 Yong Liu Si-Yuan Yao +2 位作者 Xi Zhou Shu-Zhong Liu Yan-Yan Bian 《Chinese Medical Sciences Journal》 CAS CSCD 2023年第2期109-116,共8页
Objective To investigate the clinical symptoms experienced by patients with thoracic spinal tumors and verify the associated symptoms that are predictive of a decline in muscle strength in the lower limbs.Methods A si... Objective To investigate the clinical symptoms experienced by patients with thoracic spinal tumors and verify the associated symptoms that are predictive of a decline in muscle strength in the lower limbs.Methods A single-center,retrospective cross-sectional study was conducted on in-patients diagnosed with epidural thoracic spinal tumors between January 2011 and May 2021.The study involved a review of electronic medical records and radiographs and the collection of clinical data.The differences in clinical manifestations between patients with constipation and those without constipation were analyzed.Binary logistic regression analyses were performed to identify risk factors associated with a decline in muscle strength in the lower limbs.Results A total of 227 patients were enrolled,including 131 patients with constipation and 96 without constipation.The constipation group had a significantly higher proportion of patients who experienced difficulty walking or paralysis compared to those without constipation prior to surgery(83.2%vs.17.7%,χ~2=99.035,P 0.001).Constipation(OR=9.522,95%CI:4.150±21.849,P 0.001)and urinary retention(OR=14.490,95%CI:4.543±46.213,P 0.001)were independent risk factors for muscle strength decline in the lower limbs.Conclusions The study observed that patients with thoracic spinal tumors who experienced constipation symptoms had a higher incidence of lower limb weakness.Moreover,the analysis revealed that constipation and urinary retention were independent risk factors associated with a preoperative decline in muscle strength of lower limbs. 展开更多
关键词 CONSTIPATION thoracic spinal tumors muscle strength decline preoperation surgical intervention
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Nutrient retranslocation strategies associated with dieback of Pinus species in a semiarid sandy region of Northeast China
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作者 Chang Liu Kai Wang +3 位作者 Hongzhang Kang Baoming Du Risheng Zhang Shanshan Tai 《Forest Ecosystems》 SCIE CSCD 2023年第6期763-773,共11页
In the semiarid sandy region of Northeast China,Mongolian pine(Pinus sylvestris var.mongolica)suffers dieback after the age of 35,while Japanese red pine(Pinus densiflora)and Chinese pine(Pinus tabuliformis)stay healt... In the semiarid sandy region of Northeast China,Mongolian pine(Pinus sylvestris var.mongolica)suffers dieback after the age of 35,while Japanese red pine(Pinus densiflora)and Chinese pine(Pinus tabuliformis)stay healthy.Foliar nutrient retranslocation reflects the nutrient conservation and utilization mechanism of plants in response to their habitats.However,the nutrient retranslocation strategies employed by three Pinus tree species to cope with nutrient limitations remain largely unknown.For this study,we investigated the seasonal variations in nitrogen(N)and phosphorus(P)concentrations of Mongolian pine,Japanese red pine,and Chinese pine plantations in terms of the green needles of all ages,senesced needles,and soil.Further,the N retranslocation efficiency(NRE),and P retranslocation efficiency(PRE),and correlations between the N:P ratios of needles and soil were analyzed.The results showed that,except for the spring NRE in 1-year-old needles of Mongolian pine,the spring NRE and PRE in 1-and 2-year-old needles of the three tree species were greater than zero.The autumn PRE was higher than zero for Mongolian pine,but lower than zero for Japanese red pine and Chinese pine.Among the three Pinus species,Mongolian pine showed greater spring PRE in 2-year-old needles,and PRE from 1-to 2-yearold needles,and from 2-year-old needles to litter.However,Japanese red pine had higher P concentrations and lower N:P ratios in senesced needles,while greater PRE was found in Chinese pine litter.Significant relationships between the N:P ratios were found in the current year and 1-year-old needles and soil in the Mongolian pine plantation,while there was an insignificant relationship between the N:P ratios of the needles and soil in the Chinese pine plantation.Thus,for Mongolian pine,the removal of P from needles in autumn,and higher P translocation from older needles under P-deficient soil may have contributed to the tree dieback.In contrast,Japanese red pine and Chinese pine stored P in their needles during autumn.Japanese red pine returned more P to the soil via litter,while Chinese pine maintained N:P homeostasis and increased P withdrawal prior to needle abscission. 展开更多
关键词 Nutrient use strategy Nutrient limitation Seasonal retranslocation Needle age Shelter forest decline
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Analysis of Key Physiological Characteristics of Portunus trituberculatus in Response to Short-Term Low Salinity Stress
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作者 ZHANG Xinni LIU Qi +7 位作者 WANG Jiali GAO Gao NIU Mingming CHEN Lizhi WANG Huan WANG Fangfang WANG Chunlin MU Changkao 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第3期746-754,共9页
Salinity is a significant environmental factor that can affect the survival,metamorphosis,growth and feeding of Portunus trituberculatus.In order to analyze the key physiological characteristics of P.trituberculatus i... Salinity is a significant environmental factor that can affect the survival,metamorphosis,growth and feeding of Portunus trituberculatus.In order to analyze the key physiological characteristics of P.trituberculatus in response to short-term low salinity stress,the experiments of gradually decline and recovery as well as abrupt decline in salinity were carried out.The results showed that P.trituberculatus could survive in a certain low salinity range in the short term,and salinity 12 was the lowest tolerable salinity under the present experimental conditions.The change of the hemolymph osmotic pressure displayed significant positive correlations with water salinity,and the pressure was always higher than seawater osmotic pressure.Short-term low salinity stress changed the structure and morphology of gill tissue.The expansion of gill filament ends and epithelial cell shedding were conducive to osmotic adjustment.The activities of key ion transport enzymes such as Na^(+)-K^(+)-ATPase,carbonic anhydrase and V-ATPase also changed with the osmotic regulation,while Na^(+)-K^(+)-ATPase played a dominant role.In summary,as an osmotic adjustment species,P.trituberculatus rapidly adapt to the short-term low-salinity environment by osmotic adjustment in vivo,but salinity below salinity 12 is not conducive to its survival.Our result enriched the theoretical mechanism of osmotic regulation of P.trituberculatus,providing reference for the development of aquaculture technology of P.trituberculatus. 展开更多
关键词 Portunus trituberculatus gradual/abrupt decline in salinity GILL osmotic pressure ion transport enzymes
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Gut microbiota links with cognitive impairment in amyotrophic lateral sclerosis: A multi-omics study
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作者 Zhenxiang Gong Li Ba +6 位作者 Jiahui Tang Yuan Yang Zehui Li Mao Liu Chun Yang Fengfei Ding Min Zhang 《The Journal of Biomedical Research》 CAS CSCD 2023年第2期125-137,共13页
Recently, cognitive impairments(CI) and behavioral abnormalities in patients with amyotrophic lateral sclerosis(ALS) have been reported. However, the underlying mechanisms have been poorly understood. In the current s... Recently, cognitive impairments(CI) and behavioral abnormalities in patients with amyotrophic lateral sclerosis(ALS) have been reported. However, the underlying mechanisms have been poorly understood. In the current study, we explored the role of gut microbiota in CI of ALS patients. We collected fecal samples from 35ALS patients and 35 healthy controls. The cognitive function of the ALS patients was evaluated using the Edinburgh Cognitive and Behavioral ALS Screen. We analyzed these samples by using 16S rRNA gene sequencing as well as both untargeted and targeted(bile acids) metabolite mapping between patients with CI and patients with normal cognition(CN). We found altered gut microbial communities and a lower ratio of Firmicutes/Bacteroidetes in the CI group, compared with the CN group. In addition, the untargeted metabolite mapping revealed that 26 and 17 metabolites significantly increased and decreased, respectively, in the CI group, compared with the CN group. These metabolites were mapped to the metabolic pathways associated with bile acids. We further found that cholic acid and chenodeoxycholic acid were significantly lower in the CI group than in the CN group. In conclusion, we found that the gut microbiota and its metabolome profile differed between ALS patients with and without CI and that the altered bile acid profile in fecal samples was significantly associated with CI in ALS patients. These results need to be replicated in larger studies in the future. 展开更多
关键词 amyotrophic lateral sclerosis cognitive decline gut microbiota fecal metabolites bile acids
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Association between Serum Uric Acid and the Early Marker of Kidney Function Decline among Chinese Middle-Aged and Older Population:Evidence from the China Health and Retirement Longitudinal Study
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作者 TANG Xu XU Lu +4 位作者 MENG Ruo Gu DU Yi Qing LIU Shi Jun ZHAN Si Yan XU Tao 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2023年第3期231-240,共10页
Objective To evaluate the association between serum uric acid(SUA)and kidney function decline.Methods Data was obtained from the China Health and Retirement Longitudinal Study on the Chinese middle-aged and older popu... Objective To evaluate the association between serum uric acid(SUA)and kidney function decline.Methods Data was obtained from the China Health and Retirement Longitudinal Study on the Chinese middle-aged and older population for analysis.The kidney function decline was defined as an annual estimated glomerular filtration rate(e GFR)decrease by>3 mL/min per 1.73 m^(2).Multivariable logistic regression was applied to determine the association between SUA and kidney function decline.The shape of the association was investigated by restricted cubic splines.Results A total of 7,346 participants were included,of which 1,004 individuals(13.67%)developed kidney function decline during the follow-up of 4 years.A significant dose-response relation was recorded between SUA and the kidney function decline(OR 1.14,95%CI 1.03-1.27),as the risk of kidney function decline increased by 14%per 1 mg/d L increase in SUA.In the subgroup analyses,such a relation was only recorded among women(OR 1.22,95%CI 1.03-1.45),those aged<60 years(OR 1.22,95%CI 1.05-1.42),and those without hypertension and without diabetes(OR 1.22,95%CI 1.06-1.41).Although the dose-response relation was not observed in men,the high level of SUA was related to kidney function decline(OR 1.83,95%CI 1.05-3.17).The restricted cubic spline analysis indicated that SUA>5 mg/dL was associated with a significantly higher risk of kidney function decline.Conclusion The SUA level was associated with kidney function decline.An elevation of SUA should therefore be addressed to prevent possible kidney impairment and dysfunction. 展开更多
关键词 Uric acid Glomerular filtration rate Kidney function decline
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Silent Earth:Averting the Insect Apocalypse by Dave Goulson
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作者 John Richard Schrock 《Entomotaxonomia》 CSCD 2023年第1期80-80,共1页
There is well-documented evidence for an ongoing decline in flying insect biomass.The author briefly summarizes the 26-years of Malaise trap data(Hallmann et al.2017) from German nature reserves.An additional 10-year ... There is well-documented evidence for an ongoing decline in flying insect biomass.The author briefly summarizes the 26-years of Malaise trap data(Hallmann et al.2017) from German nature reserves.An additional 10-year sweep-net study published by Seibold et al.(2019) found an even greater decline in insects on German forests and grasslands.Additional studies are cited that involve a variety of sampling methods and target butterflies,moths,aphids and other insects.Some studies go back to 1968.The results show declines of 28 to 46 percent. 展开更多
关键词 German DECLINE FORESTS
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Diabetes and cognitive decline:Challenges and future direction
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作者 Norhamidar Ab-Hamid Norsuhana Omar +1 位作者 Che Aishah Nazariah Ismail Idris Long 《World Journal of Diabetes》 SCIE 2023年第6期795-807,共13页
There is growing evidence that diabetes can induce cognitive decline and dementia.It is a slow,progressive cognitive decline that can occur in any age group,but is seen more frequently in older individuals.Symptoms re... There is growing evidence that diabetes can induce cognitive decline and dementia.It is a slow,progressive cognitive decline that can occur in any age group,but is seen more frequently in older individuals.Symptoms related to cognitive decline are worsened by chronic metabolic syndrome.Animal models are frequently utilized to elucidate the mechanisms of cognitive decline in diabetes and to assess potential drugs for therapy and prevention.This review addresses the common factors and pathophysiology involved in diabetes-related cognitive decline and outlines the various animal models used to study this condition. 展开更多
关键词 Diabetes mellitus Insulin signaling Macrovascular disease Microvascular disease Animal models Cognitive decline PATHOPHYSIOLOGY
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Coupling between the Cenozoic west Pacific subduction initiation and decreases of atmospheric carbon dioxides
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作者 Guozhi Xie Fanfan Tian +3 位作者 Kun Wang Yuanyuan Xiao Tianyu Chen Weidong Sun 《Acta Geochimica》 EI CAS CSCD 2023年第3期387-392,共6页
At the beginning of the Cenozoic,the atmospheric CO_(2)concentration increased rapidly from~2000 ppmv at 60 Ma to~4600 ppmv at 51 Ma,which is 5–10 times higher than the present value,and then continuous declined from... At the beginning of the Cenozoic,the atmospheric CO_(2)concentration increased rapidly from~2000 ppmv at 60 Ma to~4600 ppmv at 51 Ma,which is 5–10 times higher than the present value,and then continuous declined from~51 to 34 Ma.The cause of this phenomenon is still not well understood.In this study,we demonstrate that the initiation of Cenozoic west Pacific plate subduction,triggered by the hard collision in the Tibetan Plateau,occurred at approximately 51 Ma,coinciding with the tipping point.The water depths of the Pacific subduction zones are mostly below the carbonate compensation depths,while those of the Neo-Tethys were much shallower before the collision and caused far more carbonate subducting.Additionally,more volcanic ashes erupted from the west Pacific subduction zones,which consume CO_(2).The average annual west Pacific volvano eruption is 1.11 km~3,which is higher than previous estimations.The amount of annual CO_(2)absorbed by chemical weathering of additional west Pacific volcanic ashes could be comparable to the silicate weathering by the global river.We propose that the initiation of the western Pacific subduction controlled the long-term reduction of atmospheric CO_(2)concentration. 展开更多
关键词 Subduction initiation in the west Pacific Collision of the Neo-Tethys Volcano eruption rates Cenozoic CO_(2)declining Carbonate compensation depths Chemical weathering
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