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Single-cell profiling of the pig cecum at various developmental stages
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作者 Yan-Yuan Xiao Qing Zhang +9 位作者 Fei Huang Lin Rao Tian-Xiong Yao Si-Yu Yang Lei Xie Xiao-Xiao Zou Li-Ping Cai Jia-Wen Yang Bin Yang Lu-Sheng Huang 《Zoological Research》 SCIE CSCD 2024年第1期55-68,共14页
The gastrointestinal tract is essential for food digestion,nutrient absorption,waste elimination,and microbial defense.Single-cell transcriptome profiling of the intestinal tract has greatly enriched our understanding... The gastrointestinal tract is essential for food digestion,nutrient absorption,waste elimination,and microbial defense.Single-cell transcriptome profiling of the intestinal tract has greatly enriched our understanding of cellular diversity,functional heterogeneity,and their importance in intestinal tract development and disease.Although such profiling has been extensively conducted in humans and mice,the single-cell gene expression landscape of the pig cecum remains unexplored.Here,single-cell RNA sequencing was performed on 45572 cells obtained from seven cecal samples in pigs at four different developmental stages(days(D)30,42,150,and 730).Analysis revealed 12 major cell types and 38 subtypes,as well as their distinctive genes,transcription factors,and regulons,many of which were conserved in humans.An increase in the relative proportions of CD8^(+)T and Granzyme A(low expression)natural killer T cells(GZMA^(low)NKT)cells and a decrease in the relative proportions of epithelial stem cells,Tregs,RHEX^(+)T cells,and plasmacytoid dendritic cells(pDCs)were noted across the developmental stages.Moreover,the post-weaning period exhibited an up-regulation in mitochondrial genes,COX2 and ND2,as well as genes involved in immune activation in multiple cell types.Cell-cell crosstalk analysis indicated that IBP6^(+)fibroblasts were the main signal senders at D30,whereas IBP6^(−)fibroblasts assumed this role at the other stages.NKT cells established interactions with epithelial cells and IBP6^(+)fibroblasts in the D730 cecum through mediation of GZMA-F2RL1/F2RL2 pairs.This study provides valuable insights into cellular heterogeneity and function in the pig cecum at different development stages. 展开更多
关键词 Single-cell RNA-seq CECUM Bama Xiang pigs Various developmental stages Cellular heterogeneity
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Present and future of new systemic therapies for early and intermediate stages of hepatocellular carcinoma 被引量:1
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作者 Juan Jose Urquijo-Ponce Carlos Alventosa-Mateu +3 位作者 Mercedes Latorre-Sánchez Inmaculada Castelló-Miralles Moisés Diago Hepatology Unit 《World Journal of Gastroenterology》 SCIE CAS 2024年第19期2512-2522,共11页
Hepatocellular carcinoma(HCC)is a high mortality neoplasm which usually appears on a cirrhotic liver.The therapeutic arsenal and subsequent prognostic outlook are intrinsically linked to the HCC stage at diagnosis.Not... Hepatocellular carcinoma(HCC)is a high mortality neoplasm which usually appears on a cirrhotic liver.The therapeutic arsenal and subsequent prognostic outlook are intrinsically linked to the HCC stage at diagnosis.Notwithstanding the current deployment of treatments with curative intent(liver resection/local ablation and liver transplantation)in early and intermediate stages,a high rate of HCC recurrence persists,underscoring a pivotal clinical challenge.Emergent systemic therapies(ST),particularly immunotherapy,have demonstrate promising outcomes in terms of increase overall survival,but they are currently bound to the advanced stage of HCC.This review provides a comprehensive analysis of the literature,encompassing studies up to March 10,2024,evaluating the impact of novel ST in the early and intermediate HCC stages,specially focusing on the findings of neoadjuvant and adjuvant regimens,aimed at increasing significantly overall survival and recurrence-free survival after a treatment with curative intent.We also investigate the potential role of ST in enhancing the downstaging rate for the intermediate-stage HCC initially deemed ineligible for treatment with curative intent.Finally,we critically discuss about the current relevance of the results of these studies and the encouraging future implications of ST in the treatment schedules of early and intermediate HCC stages. 展开更多
关键词 Hepatocellular carcinoma Early stage Intermediate stage NEOADJUVANT ADJUVANT Systemic therapy
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Novel method for identifying the stages of discharge underwater based on impedance change characteristic
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作者 高崇 康忠健 +3 位作者 龚大建 张扬 王玉芳 孙一鸣 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第4期133-145,共13页
It is difficult to determine the discharge stages in a fixed time of repetitive discharge underwater due to the arc formation process being susceptible to external environmental influences. This paper proposes a novel... It is difficult to determine the discharge stages in a fixed time of repetitive discharge underwater due to the arc formation process being susceptible to external environmental influences. This paper proposes a novel underwater discharge stage identification method based on the Strong Tracking Filter(STF) and impedance change characteristics. The time-varying equivalent circuit model of the discharge underwater is established based on the plasma theory analysis of the impedance change characteristics and mechanism of the discharge process. The STF is used to reduce the randomness of the impedance of repeated discharges underwater, and then the universal identification resistance data is obtained. Based on the resistance variation characteristics of the discriminating resistance of the pre-breakdown, main, and oscillatory discharge stages, the threshold values for determining the discharge stage are obtained. These include the threshold values for the resistance variation rate(K) and the moment(t).Experimental and error analysis results demonstrate the efficacy of this innovative method in discharge stage determination, with a maximum mean square deviation of Scrless than 1.761. 展开更多
关键词 discharge underwater discharge stage identification impedance characteristics strong tracking filter
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Autophagy-dependent ferroptosis may play a critical role in early stages of diabetic retinopathy
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作者 Wen-Jie Sun Xue-Dong An +8 位作者 Yue-Hong Zhang Shan-Shan Tang Yu-Ting Sun Xiao-Min Kang Lin-Lin Jiang Xue-Fei Zhao Qing Gao Hang-Yu Ji Feng-Mei Lian 《World Journal of Diabetes》 SCIE 2024年第11期2189-2202,共14页
Diabetic retinopathy(DR),as one of the most common and significant microvascular complications of diabetes mellitus(DM),continues to elude effective targeted treatment for vision loss despite ongoing enrichment of the... Diabetic retinopathy(DR),as one of the most common and significant microvascular complications of diabetes mellitus(DM),continues to elude effective targeted treatment for vision loss despite ongoing enrichment of the understanding of its pathogenic mechanisms from perspectives such as inflammation and oxidative stress.Recent studies have indicated that characteristic neuroglial degeneration induced by DM occurs before the onset of apparent microvascular lesions.In order to comprehensively grasp the early-stage pathological changes of DR,the retinal neurovascular unit(NVU)will become a crucial focal point for future research into the occurrence and progression of DR.Based on existing evidence,ferroptosis,a form of cell death regulated by processes like ferritinophagy and chaperone-mediated autophagy,mediates apoptosis in retinal NVU components,including pericytes and ganglion cells.Autophagy-dependent ferroptosis-related factors,including BECN1 and FABP4,may serve as both biomarkers for DR occurrence and development and potentially crucial targets for future effective DR treatments.The aforementioned findings present novel perspectives for comprehending the mechanisms underlying the early-stage pathological alterations in DR and open up innovative avenues for investigating supplementary therapeutic strategies. 展开更多
关键词 Diabetic retinopathy Diabetes mellitus Retinal neurovascular unit Autophagy-dependent ferroptosis Early stage Mechanisms
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Nutritional Composition and Distribution of Heracleum dissectum Ledeb.at Different Growth Stages
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作者 Pan Yan Fan Lili +4 位作者 Sun Yan Li Sining Zhuang Yue Sun Haixia Zhong Rongzhen 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第3期20-32,共13页
Heracleum dissectum Ledeb.(HD)with high edible and medicinal values is distributed in Northeast Asia.To provide a reference for selecting appropriate parts and periods to harvest HD,the nutrient contents in different ... Heracleum dissectum Ledeb.(HD)with high edible and medicinal values is distributed in Northeast Asia.To provide a reference for selecting appropriate parts and periods to harvest HD,the nutrient contents in different parts of HD at three growth stages were determined.The nutrients being determined are essential nutrients closely related to human needs,and the crude protein content of HD was 3.58‒28.43 g•100 g^(-1)DW(dry weight),sugar content was 2.33‒30.92 g•100 g^(-1)DW,and soluble dietary fiber content was 9.71‒26.09 g•100 g^(-1)DW.Crude protein was mainly distributed in leaf blades and inflorescences,sugar was primarily found in roots,and dietary fiber was predominantly located in leaves.From the leaf development stage to the flowering stage and then to the late seed harvest stage,the content of moisture,crude protein and soluble sugar first decreased and then increased.In contrast,the content of dietary fiber and crude fat first increased and then decreased. 展开更多
关键词 nutrient content VEGETABLE plant organ developmental stage
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Lymph node dissection does not affect the survival of patients with tumor node metastasis stages Ⅰ and Ⅱ colorectal cancer
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作者 Fan He Shu-Pei Qu +1 位作者 Ye Yuan Kun Qian 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第8期2503-2510,共8页
BACKGROUND The effect of the number of lymph node dissections(LNDs)during radical resection for colorectal cancer(CRC)on overall survival(OS)remains controver-sial.AIM To investigate the association between the number... BACKGROUND The effect of the number of lymph node dissections(LNDs)during radical resection for colorectal cancer(CRC)on overall survival(OS)remains controver-sial.AIM To investigate the association between the number of LNDs and OS in patients with tumor node metastasis(TNM)stage Ⅰ–Ⅱ CRC undergoing radical resection.METHODS Patients who underwent radical resection for CRC at a single-center hospital between January 2011 and December 2021 were retrospectively analyzed.Cox regression analyses were performed to identify the independent predictors of OS at different T stages.RESULTS A total of 2850 patients who underwent laparoscopic radical resection for CRC were enrolled.At stage T1,age[P<0.01,hazard ratio(HR)=1.075,95%confidence interval(CI):1.019-1.134]and tumour size(P=0.021,HR=3.635,95%CI:1.210-10.917)were independent risk factors for OS.At stage T2,age(P<0.01,HR=1.064,95%CI:1.032-1.098)and overall complications(P=0.012,HR=2.297,95%CI:1.200-4.397)were independent risk factors for OS.At stage T3,only age(P<0.01,HR=1.047,95%CI:1.027-1.066)was an independent risk factor for OS.At stage T4,age(P<0.01,HR=1.057,95%CI:1.039-1.075)and body mass index(P=0.034,HR=0.941,95%CI:0.890-0.995)were independent risk factors for OS.However,there was no association between LNDs and OS in stages Ⅰ and Ⅱ.CONCLUSION The number of LDNs did not affect the survival of patients with TNM stages Ⅰ and Ⅱ CRC.Therefore,insufficient LNDs should not be a cause for alarm during the surgery. 展开更多
关键词 Lymph nodes Colorectal cancer T stage Overall survival Cox regression analyses
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Understanding changes in volatile compounds and fatty acids of Jincheng orange peel oil at different growth stages using GC-MS
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作者 XIE Jiao CAO Qi +2 位作者 WANG Wen-jun ZHANG Hong-yan DENG Bing 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第7期2282-2294,共13页
Jincheng orange(Citrus sinensis Osbeck)is widely grown in Chongqing,China,and is commonly consumed because of its characteristic aroma contributed by the presence of diverse volatile compounds.The changes in aroma dur... Jincheng orange(Citrus sinensis Osbeck)is widely grown in Chongqing,China,and is commonly consumed because of its characteristic aroma contributed by the presence of diverse volatile compounds.The changes in aroma during the development and maturation of fruit are indicators for ripening and harvest time.However,the influence of growth stages on the volatile compounds in Jincheng orange remains unclear.In addition,volatiles originate from fatty acids,most of which are the precursors of volatile substances.On this basis,gas chromatography-mass spectrometry(GC-MS)was performed to elaborate the changes in volatile constituents and fatty acids as precursors.This study tested proximately 60 volatiles and 8 fatty acids at 9 growth and development stages(AF1-AF9).Of those compounds,more than 92.00%of total volatiles and 87.50%of fatty acids were terpenoid and saturated fatty acids,respectively.As shown in the PCA plot,the AF5,AF6,and AF9 stages were confirmed as completely segregated and appeared different.In addition,most of the volatiles and fatty acids first increased at the beginning of the development stage,then decreased from the AF6 development stage,and finally increased at the AF9 maturity stage.Moreover,the highest contents of terpenoid,alcohols,aldehydes,ketones,and saturated fatty acids in Jincheng orange peel oil were d-limonene,linalool,octanal,cyclohexanone,and stearic acid during development stages,respectively.Our results found that the growth stages significantly affected the volatile constituents and precursors in Jincheng orange peel oil. 展开更多
关键词 Jincheng orange volatile compounds fatty acids growth stages
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Deformation Mechanism of Bimodal Structured 2205 Duplex Stainless Steel in Two Yield Stages
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作者 盛捷 DU Mingchen +7 位作者 LI Yufeng MA Guocai CHEN Weiqian ZHENG Yuehong ZHAN Faqi REN Junqiang G I Raab 喇培清 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第1期184-191,共8页
A kind of micro/nanostructured 2205 duplex stainless steel(DSS)with uniform distribution of nanocrystals was prepared via aluminothermic reaction method.The analysis of stress-strain curve showed that the fracture str... A kind of micro/nanostructured 2205 duplex stainless steel(DSS)with uniform distribution of nanocrystals was prepared via aluminothermic reaction method.The analysis of stress-strain curve showed that the fracture strength and elongation of the specimen were 946 MPa and 24.7%,respectively.At present,the research on microstructure of bimodal 2205 DSS at room temperature(RT)mainly depended on scanning electron microscope(SEM)observation after loading experiments.The test result indicates that there are two different yield stages in stress-strain curve of specimen during tensile process.The microstructure of duplex bimodal structured stainless steel consists of two pairs of soft hard regions and phases.By studying deformation mechanism of bimodal structured stainless steel,the interaction between soft phase and hard phase are discussed.The principle of composition design and microstructure control of typical duplex stainless steel is obtained,which provides an important research basis for designing of advanced duplex stainless steel. 展开更多
关键词 2205 duplex stainless steel bimodal structure in-situ tensile test deformation mechanism two different yield stages
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RT-qPCR normalization of reference genes in different lifehistory stages of Gracilaria vermiculophylla(Rhodophyta)
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作者 Yingyue ZHANG Jinxin YANG +2 位作者 Ze YANG Cong QI Di XU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第5期1910-1917,共8页
The quantitative realtime polymerase chain reaction(RT-qPCR)is a powerful and sensitive method to measure expression of targeted gene but it highly relies on the use of suitable reference genes for data normalization.... The quantitative realtime polymerase chain reaction(RT-qPCR)is a powerful and sensitive method to measure expression of targeted gene but it highly relies on the use of suitable reference genes for data normalization.We evaluated the expressions of 8 housekeeping genes:18S ribosomal rDNA(18S rDNA),28S ribosomal r DNA(28S rDNA),rubisco large subunit(rbc-L),β-actin(ACT),glyceraldehyde-3-phosphate dehydrogenase(GAPDH),elongation factor 1(EF1),β-tubulin(Tub B),and P-phycoerythrin B(PEB),to select the suitable reference genes for different life-history stages(tetrasporophyte,carposporophyte,and male/female gametophyte)of Gracilaria vermiculophylla by absolute quantitative method.Softwares geNorm and BestKeeper were used to verify the results acquired from copy number analysis.Results show that the expression of identified reference genes varied in comparing groups composed of different type of life stages.It is suggested that 18S rDNA and TubB could be used for highly complex samples composed of mixed ploidy and phases.18S rDNA and 28S rDNA were also preferred for using among the matured isomorphic samples.But for samples with different maturities,TubB and ACT were recommended for tetrasporophytes and gametophytes respectively. 展开更多
关键词 reference gene Gracilaria vermiculophylla life-history stage quantitative real-time polymerase chain reaction(RT-qPCR) red algae
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Rectal Cancer Stages T2 and T3 Identification Based on Asymptotic Hybrid Feature Maps
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作者 Shujing Sun Jiale Wu +4 位作者 Jian Yao Yang Cheng Xin Zhang Zhihua Lu Pengjiang Qian 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第10期923-938,共16页
Many existing intelligent recognition technologies require huge datasets for model learning.However,it is not easy to collect rectal cancer images,so the performance is usually low with limited training samples.In add... Many existing intelligent recognition technologies require huge datasets for model learning.However,it is not easy to collect rectal cancer images,so the performance is usually low with limited training samples.In addition,traditional rectal cancer staging is time-consuming,error-prone,and susceptible to physicians’subjective awareness as well as professional expertise.To settle these deficiencies,we propose a novel deep-learning model to classify the rectal cancer stages of T2 and T3.First,a novel deep learning model(RectalNet)is constructed based on residual learning,which combines the squeeze-excitation with the asymptotic output layer and new cross-convolution layer links in the residual block group.Furthermore,a two-stage data augmentation is designed to increase the number of images and reduce deep learning’s dependence on the volume of data.The experiment results demonstrate that the proposed method is superior to many existing ones,with an overall accuracy of 0.8583.Oppositely,other traditional techniques,such as VGG16,DenseNet121,EL,and DERNet,have an average accuracy of 0.6981,0.7032,0.7500,and 0.7685,respectively. 展开更多
关键词 Rectal cancer staging T2WI images data expansion asymptotic output layer
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Mid-term results of sub-trochanteric valgus osteotomy for symptomatic late stages Legg-Calvé-Perthes disease
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作者 Khaled M Emara Ramy Ahmed Diab +3 位作者 Ahmed K Emara Mohamed Eissa Mostafa Gemeah Shady Abdelghaffar Mahmoud 《World Journal of Orthopedics》 2023年第5期328-339,共12页
BACKGROUND The treatment of late stages of Legg-Calvé-Perthes disease(LCPD)is controversial.Although the concept of femoral head containment is a well-established technique of treatment,its use remains debatable ... BACKGROUND The treatment of late stages of Legg-Calvé-Perthes disease(LCPD)is controversial.Although the concept of femoral head containment is a well-established technique of treatment,its use remains debatable in the late stages of the disease,as it does not improve symptoms in terms of limb length discrepancy and gait.AIM To assess the results of subtrochanteric valgus osteotomy in symptomatic patients with late-stage Perthes disease.METHODS From 2000 to 2007,36 symptomatic patients with late stage of Perthes disease were surgically treated with subtrochanteric valgus osteotomy and followed-up for 8 to 11 years using the IOWA score and range of motion(ROM)variables.The Mose classification was also assessed at the last follow-up to reflect possible remodeling.The patients were 8 years old or older at the time of surgery,in the post-fragmentation stage,and complaining of pain,limited ROM,Trendelenburg gait,and/or abductor weakness.RESULTS The preoperative IOWA score(average:53.3)markedly improved at the 1-year post follow-up period(average:85.41)and then slightly improved at the last follow-up(average:89.4)(P value<0.05).ROM improved,with internal rotation increased on average by 22°(from 10°preoperatively to 32°postoperatively)and abduction increased on average by 15.9°(from 25°preoperatively to 41°postoperatively).The mean Mose deviation of femoral heads was 4.1 mm at the end of the follow-up period.The tests used were the paired t-test and Pearson correlation test,where the level of significance was a P value less than 0.05.CONCLUSION Subtrochanteric valgus osteotomy can be a good option for symptomatic relief in patients with late-stage of LCPD. 展开更多
关键词 Legg-Calvé-Perthes disease Femoral head avascular necrosis Valgus osteotomy Deformity correction Post fragmentation stage Late stage Perthes
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Characteristics of Soil Organic Carbon and Total Nitrogen in Rubber Plantations Soil at Different Age Stages in the Western Region of Hainan Island 被引量:17
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作者 吴志祥 谢贵水 +2 位作者 陶忠良 周兆德 王旭 《Agricultural Science & Technology》 CAS 2010年第1期147-153,共7页
[Objective]The aim was to study on the characteristics of soil organic carbon and nitrogen in rubber (Hevea brasiliensis Muell-Arg) plantations at different age stages in the western region of Hainan Island,so as to... [Objective]The aim was to study on the characteristics of soil organic carbon and nitrogen in rubber (Hevea brasiliensis Muell-Arg) plantations at different age stages in the western region of Hainan Island,so as to evaluate the ecological benefits of rubber plantations and provide basic data for studying the effect of tropical land utilization/cover change on the global carbon and nitrogen cycle. [Method]The situs was in Danzhou city,western region of Hainan Island,and the samples were four kinds of rubber plantations soil at different ages and one kind of control check (pepper,Piper nigrum L.) soil. In this research,four quadrats were set up in each sample,and the size of each was 20 cm×20 cm. Four specimens were gathered from four layers of 0-15,15-30,30-45,45-60,and the average of them was the last analysis result of each sample. Soil density was measured by cutting ring method,soil containing and hygroscopic water was detected by oven drying method,soil organic carbon (SOC) was measured by low temperature heated outside potassium dichromate oxidation-colorimetry method,and soil total nitrogen (STN) was detected by semimicro Kjeldahl method. [Result]SOC contents of different layers in rubber plantations soil at different age stages (including the CK pepper soil,the same as below) varied little,and the content of SOC in surface layer (0-15 cm) was higher,while the underlayer (45-60 cm) was lower than the average value; there was significant difference in SOC content among different kinds of soil,and the content was of 6.03-7.78 g/kg,tapping young trees (7 years) CK pepper mature age trees (30 years) prophase of young trees (2 years) tapping trees (16 years); there was no significant difference in SOC storage among different kinds of soil,and the storage was of 61.33-74.29 t/hm2,mature age trees (30 years) tapping young trees (7 years) prophase of young trees (2 years) CK pepper tapping trees (16 years); there was significant difference in STN content among rubber plantations soil at different age stages,the content was of 410.86-664.14 mg/kg2,CK pepper tapping young trees (7 years) prophase of young trees (2 years) mature age trees (30 years) tapping trees (16 years),and STN content of tapping trees (16 years) soil was extremely lowest; there was significant difference in C/N ratio among different kinds of soil,the ratio was of 10.94-14.47,and the ratio of tapping trees (16 years) mature age trees (30 years) tapping young trees (7 years) CK pepper prophase of young trees (2 years). [Conclusion]There wasn't unhealthy effect of rubber trees planted in tropical area on the content and storage of SOC,the content of STN and the ratio of C/N. there was no significant difference between rubber plantations and CK pepper soil,and the effects of rubber plantation on soil carbon-nitrogen was similar to that of other tropical crops (such as pepper). 展开更多
关键词 Different age stages of trees Rubber (Hevea brasiliensis) plantations Soil organic carbon (SOC) Soil total nitrogen (STN) Hainan Island
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Effects of Short-term High Temperature Stress on the Photosynthesis of Potato in Different Growth Stages 被引量:3
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作者 王连喜 金鑫 +3 位作者 李剑萍 马国飞 曹宁 李琪 《Agricultural Science & Technology》 CAS 2011年第3期317-321,342,共6页
[Objective] The aim was to study the effects of short-term high temperature stress on the photosynthesis of potato in different growth stages. [Method] Choosing powder potato named Longshu No.3 widely cultivated in Ni... [Objective] The aim was to study the effects of short-term high temperature stress on the photosynthesis of potato in different growth stages. [Method] Choosing powder potato named Longshu No.3 widely cultivated in Ningxia as test material,the changes of stomata conductance (Gs),transpiration rate (Tr) and CO2 concentration difference between internal and external leaf chamber,net photosynthetic rate (Pn) and photosynthetic water use efficiency (WUE) in different growth stages under short-term high temperature were analyzed. [Result] During seedling stage,the hysteretic nature of net photosynthetic rate and CO2 concentration difference between internal and external leaf chamber of potato could be found under high temperature stress,while the change trends of stomata conductance and transpiration rate under high temperature stress were consistent to that at normal temperature,but stomata conductance and transpiration rate were higher than those at normal temperature,and CO2 concentration difference between internal and external leaf chamber affected net photosynthetic rate most obviously. During branching stage,the change trends of net photosynthetic rate,CO2 concentration difference between internal and external leaf chamber,stomata conductance and transpiration rate under high temperature stress and normal temperature were similar,but they changed abruptly and reached peak value at noon under high temperature stress,while there existed consistent variation of water use efficiency under high temperature stress and at normal temperature,and CO2 concentration difference between internal and external leaf chamber also affected net photosynthetic rate most greatly,next came transpiration rate. [Conclusion] High temperature stress affected the photosynthesis of potato in different growth stages,and it was more obvious during branching stage than seedling stage,while CO2 concentration difference between internal and external leaf chamber had the most important influence on net photosynthetic rate. 展开更多
关键词 POTATO Different growth stages High temperature stress PHOTOSYNTHESIS
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Effects of Waterlogging in Different Growth Stages on Nitrogen Uptake, Distribution, and Utilization of Cotton 被引量:1
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作者 杨富强 刘瑞显 +1 位作者 张国伟 杨长琴 《Agricultural Science & Technology》 CAS 2014年第9期1503-1507,共5页
[Objective] This study aimed to investigate the effects of waterlogging in different growth stages on nitrogen (N) uptake, distribution, and utilization of cotton. [Method] A pool-culture experiment in field was con... [Objective] This study aimed to investigate the effects of waterlogging in different growth stages on nitrogen (N) uptake, distribution, and utilization of cotton. [Method] A pool-culture experiment in field was conducted to investigate the effects of wateriogging through comparing WL1 (waterlogging at peak squaring stage) and WL2 (waterlogging at flowering and boll-forming stage) treatments with their controls respectively. [Result] The results showed that the effect of WL1 on N uptake of cotton root was stronger than WL2. At 20 days (d) after WL1 treatment, the root biomass (RB), N uptake (NU), and N uptake rate (NUR) significantly decreased by 38.1%, 48.6%, and 53.0% respectively. At 20 d after WL2 treatment, the RB, NU, and NUR significantly decreased by 27.3%, 46.0%, and 44.8% respectively. More N was distributed to root and leaf after WL1 treatment, and to square, flower, and boll after WL2 treatment. N physiological use efficiency increased by 11.4% and 44.4% after WL1 and WL2 treatments respectively. Further analysis showed that the effects of WL1 on yield and its components of cotton were stronger than WL2. The boll number, boll weight, and lint yield per plant significantly reduced by 40.5%, 12.4%, and 49.5% after WL1 treatment, and significantly decreased by 23.1%, 6.9%, and 29.9% after WL2 treatment, respectively. [Conclusion] The negative effects of water- logging at peak squaring stage on N nutrition and yield of cotton were stronger than waterlogging at flowering and boll-forming stage, indicating that more attention should be paid to waterlogging at peak squaring stage and sound N management can improve cotton regrowth and reduce yield loss after waterlogging. 展开更多
关键词 Growth stages WATERLOGGING COTTON NITROGEN
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Histologic Classification of Thymoma and Its Relationship with Myasthenia Gravis and Clinical Stages of the Tumor 被引量:1
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作者 王新允 陈云新 +1 位作者 王爱香 张淑敏 《The Chinese-German Journal of Clinical Oncology》 CAS 2005年第5期314-316,327,共4页
Objective: To investigate the relationship among the latest WHO classification of thymoma, myasthenia gravis (MG) and clinical stages. Methods: To review the pathological sections of 74 patients with thymoma from ... Objective: To investigate the relationship among the latest WHO classification of thymoma, myasthenia gravis (MG) and clinical stages. Methods: To review the pathological sections of 74 patients with thymoma from 1980-2004 using WHO classification (1999), the statistical software was used to analyze the relationship among the WHO classification, MG and clinical stages. Results: (1) Two cases of type A, 23 cases of type AB, 4 cases of type B1, 27 cases of type B2, 16 cases of type B3 and 2 cases of type C were classified. Type B2 more likely accompanied MG (P〈0.05), while none with MG occurred for type C. (2) One patient was in stage Ⅰ, 30 were in stage Ⅱ, 38 were in stage Ⅲ, and 5 were in stage Ⅳ. The latest histologic classification was significantly correlated with Masaoka stages (P〈0.01). Conclusion: The latest WHO classification was correlated with occurrence of MG and finely reflected clinical stage. It can also evaluate the prognosis of patients. 展开更多
关键词 THYMOMA myasthenia gravis clinical stages
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Improvement of pump-probe optical measurement technique using double moving stages
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作者 张春伟 赵伟玮 +4 位作者 毕可东 雍国清 高雪松 王建立 陈云飞 《Journal of Southeast University(English Edition)》 EI CAS 2013年第4期414-418,共5页
In order to improve the measurement precision and increase the reliability of the femtosecond laser transient thermoreflectance system, the relative optical path difference between pump and probe beams is prolonged, w... In order to improve the measurement precision and increase the reliability of the femtosecond laser transient thermoreflectance system, the relative optical path difference between pump and probe beams is prolonged, which can improve the fitting accuracy of the experimental data to the theoretical model. A modified experimental setup is devised with the pump path intercalated a moving stage identical to the one in the probe path, which extends the optical path difference of the probe beam relative to the pump beam from 4 to 8 ns. The measured results indicate that the uncertainty from the misalignment and divergence of both beams can be ignored when the last 4 ns experimental data are connected with those of the first 4 ns smoothly. The as-obtained thermal conductance of AI/Si and Cr/Si interfaces agrees well with the reported experimental values, which verifies the reliability of this modified version of this measurement. 展开更多
关键词 femtosecond laser transient thermoreflectance double moving stages interfacial thermal conductance
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Descriptions of the Immature Stages of Three Species of the Tribe Ozophorini (Heteroptera:Lygaeidae:Rhyparochrominae) from China
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作者 薛怀君 卜文俊 《Entomotaxonomia》 CSCD 北大核心 2004年第4期264-271,共8页
Immature stages of 3 species of the tribe Ozophorini from China are described for the first time, they are Bryanellocoris orientalis Hidaka (3rd^5th instars), Primierus longispinus Zheng (4th^5th instars) and Vertoman... Immature stages of 3 species of the tribe Ozophorini from China are described for the first time, they are Bryanellocoris orientalis Hidaka (3rd^5th instars), Primierus longispinus Zheng (4th^5th instars) and Vertomannus brevicollum Zheng (4th^5th instars). Abrief study on fine structure of pale spots on head, pronotum and abdomen of 5th instar nymph of Bryanellocoris orientalis Hidaka was also given. 展开更多
关键词 HETEROPTERA Ozophorini immature stages LYGAEIDAE fine structure
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Descriptions of Male and Immature Stages of Cryptococcus ulmi Tang et Hao (Homoptera: Coccoidea: Eriococcidae) with Brief Notes on Its Biology
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作者 武三安 《Entomotaxonomia》 CSCD 2000年第4期251-256,共6页
In this paper, the crawler, second instar female and male, prepupa, pupa and adult male of Cryptococcus ulmi are described and illustrated for the first time; adult female is redescribed; a key to all stages is gi... In this paper, the crawler, second instar female and male, prepupa, pupa and adult male of Cryptococcus ulmi are described and illustrated for the first time; adult female is redescribed; a key to all stages is given and the biology is briefly repor ted. 展开更多
关键词 morphology immature stages adult male BIOLOGY Cryptococcus ulmi
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The Christian Doctrines of Salvation at the Earlier Stages of The Pilgrim's Progress
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作者 林雅琴 《海外英语》 2011年第9X期278-279,共2页
John Bunyan's The Pilgrim's Progress has been written to preach the Christian doctrines of salvation.Therefore its allegorical protagonists have gradually gone through four stages of development on the path to... John Bunyan's The Pilgrim's Progress has been written to preach the Christian doctrines of salvation.Therefore its allegorical protagonists have gradually gone through four stages of development on the path to salvation.This paper is focused on the earlier two stages,that is,the repentance of sins and the temptations after conversion. 展开更多
关键词 John Bunyan The Pilgrim’s PROGRESS CHRISTIAN doctrines of SALVATION FOUR stages
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Nitrate Effect on Rice Growth and Nitrogen Absorption and Assimilation at Different Growth Stages 被引量:26
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作者 DUAN Ying-Hua ZHANG Ya-Li SHEN Qi-Rong WANG Song-Wei 《Pedosphere》 SCIE CAS CSCD 2006年第6期707-717,共11页
The effect of nitrate (NO3^-) on rice (Oryza sativa L.) growth as well as N absorption and assimilation during different growth stages was examined using three typical rice cultivars. Dry weight, yield, N uptake, ... The effect of nitrate (NO3^-) on rice (Oryza sativa L.) growth as well as N absorption and assimilation during different growth stages was examined using three typical rice cultivars. Dry weight, yield, N uptake, nitrate reductase activity (NRA) in leaves, and glutamine synthetase activity (GSA) in roots and leaves during their entire growth periods, as well as the kinetic parameters of ammonium (NH4^+) uptake at the seedling stage, were measured with solution culture experiments. Results indicated that addition of NH4^+-N and NO3^-N at a ratio of 75:25 (NH4^++NO3^- treatment) when compared with that of NH4^+-N alone (NH4^+ treatment) increased the dry weight of ‘Nanguang' cultivar by 30% and ‘Yunjing 38' cultivar by 31%, and also increased their grain yield by 21% and 17%, respectively. For the four growth stages, the total N accumulation in plants increased by an average of 36% for ‘Nanguang' and 31% for ‘Yunjing 38', whereas the increasing effect of NO3^- in the ‘4007' cultivar was only found at the seedling stage, in the NH4^++NO3^- treatment compared to the NH4^+ treatment, NRA in the leaves increased by 2.09 folds, and GSA increased by 92% in the roots and 52% in the leaves of the three cultivars. NO3^- supply increased the maximum uptake rate (Vmax) in the ‘Nanguang' and ‘Yunjing 38' cultivars, reflecting that the NO3^- itself, not the increasing N concentration, increased the uptake rate of NH4^+ by rice. There was no effect on the apparent Michaelis-Menten constant (Kin) of the three cultivars. Thus, some replacement of NH4^+ with NO3^-could greatly improve the growth of rice plants, mainly on account of the increased uptake of NH4^+ promoted by NO3^-, and future studies should focus on the molecular mechanism of the increased uptake of NH4^+ by NO3^-. 展开更多
关键词 growth stages N absorption and assimilation NITRATE N uptake RICE
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