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Reproductive height determines the loss of clonal grasses with nitrogen enrichment in a temperate grassland
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作者 Xu Chen Haining Lu +4 位作者 Zhengru Ren Yuqiu Zhang Ruoxuan Liu Yunhai Zhang Xingguo Han 《Plant Diversity》 SCIE CAS CSCD 2024年第2期256-264,共9页
Tall clonal grasses commonly display competitive advantages with nitrogen(N)enrichment.However,it is currently unknown whether the height is derived from the vegetative or reproductive module.Moreover,it is unclear wh... Tall clonal grasses commonly display competitive advantages with nitrogen(N)enrichment.However,it is currently unknown whether the height is derived from the vegetative or reproductive module.Moreover,it is unclear whether the height of the vegetative or reproductive system regulates the probability of extinction and colonization,and determines species diversity.In this study,the impacts on clonal grasses were studied in a field experiment employing two frequencies(twice a year vs.monthly)crossing with nine N addition rates in a temperate grassland,China.We found that the N addition decreased species frequency and increased extinction probability,but did not change the species colonization probability.A low frequency of N addition decreased species frequency and colonization probability,but increased extinction probability.Moreover,we found that species reproductive height was the best index to predict the extinction probability of clonal grasses in N-enriched conditions.The low frequency of N addition may overestimate the negative effect from N deposition on clonal grass diversity,suggesting that a higher frequency of N addition is more suitable in assessing the ecological effects of N deposition.Overall,this study illustrates that reproductive height was associated with the clonal species extinction probability under N-enriched environment. 展开更多
关键词 ANPP Biodiversity clonal grass COLONIZATION EXTINCTION Nitrogen addition frequency
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Clonal hematopoiesis:a shared risk factor for cardiovascular diseases and tumors
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作者 Ling-Feng Zha Xiang Cheng 《Oncology and Translational Medicine》 2024年第1期35-41,共7页
Clonal hematopoiesis(CH)is a clonally expanded population of hematopoietic stem cells carrying somatic mutations that differentiate through multilineage hematopoiesis to form terminally differentiated mature hematopoi... Clonal hematopoiesis(CH)is a clonally expanded population of hematopoietic stem cells carrying somatic mutations that differentiate through multilineage hematopoiesis to form terminally differentiated mature hematopoietic cells carrying markers of the clonal mutation.Genes integral to critical cellular processes such as epigenetic regulation,DNA damage response,and inflammation frequently carry these mutations.Clonal hematopoiesis becomes increasingly prevalent with age and is associated with an increased risk of hematological tumors and some nonhematological conditions.Recent insights have revealed that the mutations driving CH are not only implicated in hematologic neoplasms but also possess the potential to influence cardiovascular pathogenesis.Here,we reviewed up-to-date findings about the roles of CH in cardiovascular diseases and tumors and explored the clinical significance of CH,as well as look forward to future related studies,so as to provide valuable references for future research and clinical practice. 展开更多
关键词 Cardiovascular diseases clonal hematopoiesis TUMORS
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Clonal Transgenerational Effects Transmit for Multiple Generations in a Floating Plant 被引量:1
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作者 Xiao-Mei Zhang Yu Jin +4 位作者 Wei Xue Jun-Qin Gao Ning-Fei Lei Jin-Song Chen Fei-Hai Yu 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第5期1589-1601,共13页
Environmental conditions of a parent plant can influence the performance of their clonal offspring,and such clonal transgenerational effects may help offspring adapt to different environments.However,it is still uncle... Environmental conditions of a parent plant can influence the performance of their clonal offspring,and such clonal transgenerational effects may help offspring adapt to different environments.However,it is still unclear how many vegetative generations clonal transgenerational effects can transmit for and whether it depends on the environmental conditions of the offspring.We grew the ancestor ramets of the floating clonal plant Spirodela polyrhiza under a high and a low nutrient level and obtained the so-called 1^(st)-generation offspring ramets of two types(from these two environments).Then we grew the 1^(st)-generation offspring ramets of each type under the high and the low nutrient level and obtained the so-called 2^(nd)-generation offspring ramets of four types.We repeated this procedure for another five times and analyzed clonal transgenerational effects on growth,morphology and biomass allocation of the 1^(st)-to the 6^(th)-generation offspring ramets.We found positive,negative or neutral(no)transgenerational effects of the ancestor nutrient condition on the offspring of S.polyrhiza,depending on the number of vegetative generations,the nutrient condition of the offspring environment and the traits considered.We observed significant clonal transgenerational effects on the 6^(th)-generation offspring;such effects occurred for all three types of traits(growth,morphology and allocation),but varied depending on the nutrient condition of the offspring environment and the traits considered.Our results suggest that clonal transgenerational effects can transmit for multiple vegetative generations and such impacts can vary depending on the environmental conditions of offspring. 展开更多
关键词 clonal plant clonal parental effect maternal effect transgenerational plasticity multi-generation experiment
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Effect of Light Intensity and Nutrient Availability on Clonal Growth and Clonal Morphology of the Stoloniferous Herb Halerpestes ruthenica 被引量:8
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作者 于飞海 董鸣 《Acta Botanica Sinica》 CSCD 2003年第4期408-416,共9页
In a greenhouse experiment plasticity of clonal growth and clonal morphology of the stoloniferous rosette herb Halerpestes nahenica Ovcz. in response to differing levels of light intensity and nutrient availability wa... In a greenhouse experiment plasticity of clonal growth and clonal morphology of the stoloniferous rosette herb Halerpestes nahenica Ovcz. in response to differing levels of light intensity and nutrient availability was studied. Total plant dry weight, leaf area of primary ramets, total number of ramets and of stolons, and total stolon length were significantly reduced, while specific internode length and specific petiole length significantly increased under deep shading (6.25% of high light intensity, 5.3% of full daylight) or under low nutrient availability. Under low nutrient availability, mean stolon internode length of H. ruthenica was significantly larger while branching intensity and number of ramets smaller than those under high nutrient availability. These responses are consistent with the foraging model of clonal plants, indicating that H. nahenica is able to forage nutrients through the plastic responses of clonal growth and clonal. morphology when it grows in heterogeneous environments. However, under deep shading, both mean stolon internode length and mean petiole length were significantly reduced, which disagrees with the findings of many other stoloniferous herbs in response to low or medium levels of shading (ca. 13%-75% of high light intensity, >10% of full daylight), suggesting that under deep shading stoloniferous herbs may not forage light through the plastic responses of spacer length. Many traits such as total plant dry weight, total number and length of stolons, total length of secondary and tertiary stolons. total number of ramets, leaf area of primary ramets and branching intensity were markedly influenced by the interaction effect of light intensity and nutrient availability. Under high light intensity nutrient availability affected these traits more pronouncedly, however under low light intensity nutrient availability either did not affect or affected less markedly on these traits, indicating that fight intensity had significant effect on nutrient foraging in H. nahenica. Under deep shading or low nutrient availability, H. ruthenica may increase its mean stolon internode length by means of thinning stolon internodes (i.e., an increase in specific internode length), which provides it with more chance to escape from resource-poor sites. 展开更多
关键词 clonal growth clonal morphology foraging behavior Halerpestes ruthenica LIGHT NUTRIENT PLASTICITY
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A Comparative Study on Photosynthesis and Water Use Efficiency Between Clonal and Non_clonal Plant Species Along the Northeast China Transect (NECT) 被引量:30
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作者 蒋高明 董鸣 《Acta Botanica Sinica》 CSCD 2000年第8期855-863,共9页
Net photosynthesis ( P n ), transpiration ( E ), stomatal conductance ( g s) and water use efficiency (WUE) of more than 218 species belonging to two different reproductive functional types, i.e. clonal (115 ... Net photosynthesis ( P n ), transpiration ( E ), stomatal conductance ( g s) and water use efficiency (WUE) of more than 218 species belonging to two different reproductive functional types, i.e. clonal (115 species) and non_clonal species (103 species), along the 1 670 km Northeast China Transect (NECT) were analyzed. The results showed that P n and WUE appeared to be lower in the east and west ends of NECT, with peaks in the middle. Transpiration was found to be higher in the west end, where most temperate desert species were distributed. On the same site, most clonal species showed higher P n and related physiological variables than non_clonal species. For different growth forms over NECT, e.g. forest trees, shrubs and grasses, meadow steppe shrubs and grasses, typical steppe shrubs and grasses, the meadow steppe and typical steppe grasses, showed higher values of physiological variables than the forest or the desert species. But for the two reproductive plant functional types (PFTs), clonal species had higher physiological variables, with averages of 22%, 15%, 23% and 14% higher than the non_clonal ones for P n , E, g s, and WUE, respectively. Such differences indicated that clonal species might have advantages over non_clonal species in utilizing environmental resources such as light, CO 2, and especially water. 展开更多
关键词 PHOTOSYNTHESIS clonal species non_clonal species forest STEPPE warm desert Northeast China Transect
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OPTIMIZATION OF AIRPORT TAXIING PLANNING DURING CONGESTED HOURS BASED ON IMMUNE CLONAL SELECTION ALGORITHM 被引量:1
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作者 柳青 吴桐水 宋祥波 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第3期294-301,共8页
In order to ease congestion and ground delays in major hub airports, an aircraft taxiing scheduling optimization model is proposed with schedule time as the object function. In the new model, the idea of a classical j... In order to ease congestion and ground delays in major hub airports, an aircraft taxiing scheduling optimization model is proposed with schedule time as the object function. In the new model, the idea of a classical job shop-schedule problem is adopted and three types of special aircraft-taxi conflicts are considered in the constraints. To solve such nondeterministic polynomial time-complex problems, the immune clonal selection algorithm(ICSA) is introduced. The simulation results in a congested hour of Beijing Capital International Airport show that, compared with the first-come-first-served(FCFS) strategy, the optimization-planning strategy reduces the total scheduling time by 13.6 min and the taxiing time per aircraft by 45.3 s, which improves the capacity of the runway and the efficiency of airport operations. 展开更多
关键词 aircraft taxiing schedule airport operation control hub airport congested hours immune clonal selection algorithm(ICSA)
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Role of Clonal Integration among Different Environmental Conditions (A Review) 被引量:1
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作者 Wajahat Husain Jaafry Dezhi Li +1 位作者 Syeda Amber Fatima Muhammad Hassan 《Natural Science》 2016年第11期475-486,共12页
Most of the ecosystems are dominated by clonal species. The most unique feature of clonal plants is their capability for clonal integration (translocation of vital resources among connected ramets), implying that inte... Most of the ecosystems are dominated by clonal species. The most unique feature of clonal plants is their capability for clonal integration (translocation of vital resources among connected ramets), implying that integration may play an essential role in their success. However, a general effect of clonal integration on plant performance is lacking. We conducted a text review on the effects of clonal integration on different habitats and species. Overall, clonal integration increased performance of clonal plants in different habitats. However clonal integration has also some limitations under stressful environments. Benefits of clonal integration may lack somehow when environmental stress increases. But connected ramets placed in unfavorable patches benefited more from integration compared to severed ramet placed in nutrient rich patches. Climate change and temperature increase have positive effects on biomass of clonal species. 展开更多
关键词 clonal Integration HABITATS clonal Plants
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Modular growth and clonal propagation of Hippophae rhamnoides subsp, sinensis in response to irrigation intensity 被引量:16
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作者 Zilin Cao Tianjiang Li +5 位作者 Genqian Li Chunhong Liu Haiyin Gao Guanghui Dai Zhiyong Xiao Sunling Li 《Journal of Forestry Research》 SCIE CAS CSCD 2016年第5期1019-1028,共10页
A multipurpose clone plant species, Hippophae rhamniodes has the capacity for indefinite longevity, although under successive drought stress it may often decline or die across large areas. Field trials were con- ducte... A multipurpose clone plant species, Hippophae rhamniodes has the capacity for indefinite longevity, although under successive drought stress it may often decline or die across large areas. Field trials were con- ducted over 2 years to examine the effects of varied irrigation intensities on modular growth and clonal propagation in a semi-arid area. Irrigation levels included a control, as well as two, four and six times the volume of water that was typically received via local annual average precipitation. Irrigation intensity significantly influenced clonal propagation capacity (number of daughter ramets), aboveground modular growth (height, base diameter, and crown width), belowground modular growth included root nodule dry weight, stretching capacity of lateral roots (length of the longest lateral roots, and diameter of first-grade lateral roots), and branching intensity of lateral roots (number of lateral roots bifurcation grade, number of first- grade lateral roots). The modular growth and the density of daughter ramets were small under non-irrigation or low irrigation, and became larger with increased irrigation intensity. Beyond a certain threshold, however, further increases in irrigation intensity resulted in a reversion to the development. The optimal irrigation intensities for growth and propagation were 3.48-5.29 times the volume of nominal local annual average precipitation. There were effects of irrigation intensities on the positive significant correlations between aboveground and belowground modular growths, and on clonal propagation capacities. Under various water treatments, H. rhamnoides may adapt to the environment through the regulation of growth and propagation. We concluded that water shortages act to weaken the growth and propagation of H. rhamniodes plantations. 展开更多
关键词 clonal propagation Hippophae rhamnoides subsp sinensis Irrigation intensity Modular growth
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Clonality analysis of neuroendocrine cells in gastric adenocarcinoma 被引量:5
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作者 Ling-Ling Wang Gen-You Yao +2 位作者 Zhong-Sheng Zhao Xiao-Li Wei Ru-Jun Xu 《World Journal of Gastroenterology》 SCIE CAS 2013年第32期5340-5346,共7页
AIM:To achieve a better understanding of the origination of neuroendocrine(NE)cells in gastric adenocarcinoma.METHODS:In this study,120 cases of gastric adenocarcinoma were obtained.First,frozen section-immunohistoche... AIM:To achieve a better understanding of the origination of neuroendocrine(NE)cells in gastric adenocarcinoma.METHODS:In this study,120 cases of gastric adenocarcinoma were obtained.First,frozen section-immunohistochemistrical samples were selected from a large quantity of neuroendocrine cells.Second,laser capture microdissection was used to get target cells from gastric adenocarcinoma and whole genome amplification was applied to get a large quantity of DNA for further study.Third,genome-wide microsatellite abnormalities[microsatellite instability(MSI),loss of heterozygosity (LOH)]and p53 mutation were detected by polymerase chain reaction(PCR)-single-strand conformation polymer-phism-silver staining and PCR-sequencing in order to identify the clonality of NE cells.RESULTS:The total incidence rate of MSI was 27.4%,while LOH was 17.9%.Ten cases had a highest concordance for the two types of cells.The other samples had similar microsatellite changes,except for cases 7 and10.Concordant p53 mutations exhibited in sample 4,14,21 and 27,and there were different mutations between two kinds of cells in case 7.In case 17,mutation took place only in adenocarcinoma cells.p53 mutation was closely related with degree of differentiation,tumor-node-metastasis stage,vessel invasion and lymph node metastasis.In brief,NE and adenocarcinoma cells showed the same MSI,LOH or p53 mutation in most cases(27/30).In the other three cases,different MSI,LOH or p53 mutation occurred.CONCLUSION:NE and the gastric adenocarcinoma cells may mainly derive from the same stem cells,but the remaining cases showing different origin needs further investigation. 展开更多
关键词 NEUROENDOCRINE DIFFERENTIATION clonal analysis GASTRIC ADENOCARCINOMA NEUROENDOCRINE CELLS
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Clonal Selection Based Memetic Algorithm for Job Shop Scheduling Problems 被引量:4
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作者 Jin-hui Yang Liang Sun +2 位作者 Heow Pueh Lee Yun Qian Yan-chun Liang 《Journal of Bionic Engineering》 SCIE EI CSCD 2008年第2期111-119,共9页
A clonal selection based memetic algorithm is proposed for solving job shop scheduling problems in this paper. In the proposed algorithm, the clonal selection and the local search mechanism are designed to enhance exp... A clonal selection based memetic algorithm is proposed for solving job shop scheduling problems in this paper. In the proposed algorithm, the clonal selection and the local search mechanism are designed to enhance exploration and exploitation. In the clonal selection mechanism, clonal selection, hypermutation and receptor edit theories are presented to construct an evolutionary searching mechanism which is used for exploration. In the local search mechanism, a simulated annealing local search algorithm based on Nowicki and Smutnicki's neighborhood is presented to exploit local optima. The proposed algorithm is examined using some well-known benchmark problems. Numerical results validate the effectiveness of the proposed algorithm. 展开更多
关键词 job shop scheduling problem clonal selection algorithm simulated annealing global search local search
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Liver cell adenoma:A case report with clonal analysis and literature review 被引量:6
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作者 Li Gong Qin Su +3 位作者 Wei Zhang Ai-Ning Li Shao-Jun Zhu Ying-Ming Feng 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第13期2125-2129,共5页
We report a case of liver cell adenoma (LCA) in a 33-year-old female patient with special respect to its clonality status, pathogenic factors and differential diagnosis. The case was examined by histopathology, immu... We report a case of liver cell adenoma (LCA) in a 33-year-old female patient with special respect to its clonality status, pathogenic factors and differential diagnosis. The case was examined by histopathology, immunohistochemistry and a clonality assay based on X-chromosomal inactivation mosaicism in female somatic tissues and polymorphism at androgen receptor focus. The clinicopathological features of the reported cases from China and other countries were compared. The lesion was spherical, sizing 2 cm in its maximal dimension. Histologically, it was composed of cells arranged in cords, most of which were two-cell-thick and separated by sinusoids. Focal fatty change and excessive glycogen storage were observed. The tumor cells were round or polygonal in shape, resembling the surrounding parenchymal cells. Mitosis was not found. No portal tract, central vein or ductule was found within the lesion. The tumor tissue showed a positive reaction for cytokeratin (CK) 18, but not for CK19, vimentin, estrogen and progesterone receptors. Monoclonality was demonstrated for the lesion, confirming the diagnosis of an LCA. Clonality analysis is helpful for its distinction from focal nodular hyperplasia.K 展开更多
关键词 Liver Cell adenoma clonalITY Literature review
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Interclonal and within-tree variation in wood properties of poplar clones 被引量:5
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作者 方升佐 杨文忠 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第4期263-268,共6页
The wood basic density, cellulose content and fiber form were investigated for all sample trees at breast height (1.3 m) in seven poplar clones, and at 0 (butt), 5.6, 9.6, 13.6, 17.6, 19.6 and 21.6 m for clone Nanlin-... The wood basic density, cellulose content and fiber form were investigated for all sample trees at breast height (1.3 m) in seven poplar clones, and at 0 (butt), 5.6, 9.6, 13.6, 17.6, 19.6 and 21.6 m for clone Nanlin-95 and Nanlin-895, respectively, for providing information on variation patterns of wood density, fiber characteristics and holocellulose content within trees and among clones. The results showed that significant variations about wood density, cellulose content, fiber diameter and the ratio of fiber length to diameter existed among poplar clones examined. Variance analysis indicated that there were significant differences in wood basic density, fiber length, fiber diameter and cellulose content among the growth rings, which had an increasing tendency along the direction from pith to bark. The significant differences also existed in wood basic density, fiber length and fiber diameter at different tree height. The mean wood basic density had a general increase trend with increasing height of trees and the lowest was found at the base, while fiber length and fiber diameter had a general decline pattern with increasing height of trees and the biggest value was observed at the height of 5.6 m. Regression analysis indicated that the relationship between examined wood properties and growth ring number (cambial age), and the relationship between examined wood properties and tree height can be described by polynomial functions. 展开更多
关键词 Poplar clone Wood basic density Fiber characteristics Cellulose content clonal variation Within-tree variation
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权重自适应clonal选择算法及其应用研究
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作者 李勇 王昱 《控制工程》 CSCD 北大核心 2011年第1期96-99,共4页
在求解两个目标以上的多目标优化问题时,基于Pareto支配的多目标进化算法多数需要较长的求解时间。基于固定权重的聚合函数方法求解速度快,但要确定一个适合待求解问题的合理权重是十分困难的,为了解决这一问题,将clonal选择算法与权重... 在求解两个目标以上的多目标优化问题时,基于Pareto支配的多目标进化算法多数需要较长的求解时间。基于固定权重的聚合函数方法求解速度快,但要确定一个适合待求解问题的合理权重是十分困难的,为了解决这一问题,将clonal选择算法与权重自适应方法相结合,提出了一种适用于多目标优化问题的权重自适应clonal选择算法。并将权重自适应clon-al选择算法应用于以等功率裕量、轧制能耗及带钢打滑概率作为优化的目标函数的三目标优化模型进行冷连轧轧制规程多目标优化。结果表明,与实际应用的轧制规程相比优化后的轧制规程使功率裕量更加均衡,打滑发生的机率变小,同时也降低了总的轧制能耗。与权重自适应遗传算法相比,该算法能更好的达到预期的优化效果。 展开更多
关键词 权重自适应 clonal选择算法 冷连轧机 轧制规程 多目标优化
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Clonality and allelotype analyses of focal nodular hyperplasia compared with hepatocellular adenoma and carcinoma 被引量:5
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作者 Yi-Ran Cai Li Gong +8 位作者 Xiao-Ying Teng Hong-Tu Zhang Cheng-Feng Wang Guo-Lian Wei Lei Guo Fang Ding Zhi-Hua Liu Qin-Jing Pan Qin Su 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第37期4695-4708,共14页
AIM: To identify clonality and genetic alterations in focal nodular hyperplasia (FNH) and the nodules derived from it. METHODS: Twelve FNH lesions were examined. Twelve hepatocellular adenomas (HCAs) and 22 hepa... AIM: To identify clonality and genetic alterations in focal nodular hyperplasia (FNH) and the nodules derived from it. METHODS: Twelve FNH lesions were examined. Twelve hepatocellular adenomas (HCAs) and 22 hepatocellular carcinomas (HCCs) were used as references. Nodules of different types were identified and isolated from FNH by microdissection. An X-chromosome inactivation assay was employed to describe their clonality status. Loss of heterozygosity (LOH) was detected, using 57 markers, for genetic alterations.RESULTS: Nodules of altered hepatocytes (NAH), the putative precursors of HCA and HCC, were found in all the FNH lesions. Polyclonality was revealed in 10 FNH lesions from female patients, and LOH was not detected in any of the six FNH lesions examined, the results apparently showing their polyclonal nature. In contrast, monoclonality was demonstrated in all the eight HCAs and in four of the HCCs from females, and allelic imbalances were found in the HCAs (9/9) and HCCs (15/18), with chromosomal arms 11p, 13q and 17p affected in the former, and 6q, 8p, 11p, 16q and 17p affected in the latter lesions in high frequencies (≥ 30%). Monodonality was revealed in 21 (40%) of the 52 microdissected NAH, but was not found in any of the five ordinary nodules. LOH was found in all of the 13 NAH tested, being highly frequent at six loci on 8p, 11p, 13q and 17p. CONCLUSION: FNH, as a whole, is polyclonal, but some of the NAH lesions derived from it are already neoplastic and harbor similar allelic imbalances as HCAs. 展开更多
关键词 clonality analysis Focal nodular hyperplasia Hepatocellular adenoma Liver tumorigenesis Loss of heterozygosity Nodules of altered hepatocytes
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Profiling of hepatocellular carcinoma neoantigens reveals immune microenvironment and clonal evolution related patterns 被引量:4
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作者 Zhenli Li Geng Chen +6 位作者 Zhixiong Cai Xiuqing Dong Lei He Liman Qiu Yongyi Zeng Xiaolong Liu Jingfeng Liu 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2021年第3期364-378,共15页
Objective: Neoantigens derived from tumor-specific genomic alterations have demonstrated great potential for immunotherapeutic interventions in cancers. However, the comprehensive profile of hepatocellular carcinoma(H... Objective: Neoantigens derived from tumor-specific genomic alterations have demonstrated great potential for immunotherapeutic interventions in cancers. However, the comprehensive profile of hepatocellular carcinoma(HCC) neoantigens and their complex interplay with immune microenvironment and tumor evolution have not been fully addressed.Methods: Here we integrated whole exome sequencing data, transcriptome sequencing data and clinical information of 72 primary HCC patients to characterize the HCC neoantigen profile, and systematically explored its interactions with tumor clonal evolution, driver mutations and immune microenvironments.Results: We observed that higher somatic mutation/neoantigen load was associated with better clinical outcomes and HCC patients could be further divided into two subgroups with distinct prognosis based on their neoantigen expression patterns. HCC subgroup with neoantigen expression probability high(NEP-H) showed more aggressive pathologic features including increased incidence of tumor thrombus(P=0.038), higher recurrence rate(P=0.029),more inclined to lack tumor capsule(P=0.026) and with more microsatellite instability sites(P=0.006). In addition,NEP-H subgroup was also characterized by higher chance to be involved in tumor clonal evolution [odds ratio(OR)=46.7, P<0.001]. Gene set enrichment analysis revealed that upregulation of MYC and its targets could suppress immune responses, leading to elevated neoantigen expression proportion in tumor cells. Furthermore, we discovered an immune escape mechanism that tumors could become more inconspicuous by evolving subclones with less immunogenicity. We observed that smaller clonal mutation clusters with higher immunogenicity in tumor were more likely to involve in clonal evolution. Based on identified neoantigen profiles, we also discovered series of neoantigenic hotspot genes, which could serve as potential actionable targets in future.Conclusions: Our results revealed the landscape of HCC neoantigens and discovered two clinically relevant subgroups with distinct neoantigen expression patterns, suggesting the neoantigen expression should be fully considered in future immunotherapeutic interventions. 展开更多
关键词 Immune microenvironment immune escape MYC regulation NEOANTIGEN tumor clonal evolution
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Study on Clonal Growth Pattern of Sabina vulgaris in Mu Us Sandland 被引量:3
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作者 ZhangGuosheng LiuHaidong +3 位作者 LiuMeizhent WangLinhe ZhuJinzhao Jirigele 《Forestry Studies in China》 CAS 2003年第2期10-16,共7页
The clonal growth pattern of Sabina vulgaris, a coniferous clonal plant in Mu Us sandland, Inner Mongolia Autonomous Region was surveyed. The results showed that with the stolon extending, internode length and branchi... The clonal growth pattern of Sabina vulgaris, a coniferous clonal plant in Mu Us sandland, Inner Mongolia Autonomous Region was surveyed. The results showed that with the stolon extending, internode length and branching angle decreased, the branching intensity increased gradually within the 3 m range from the edge of the shrub to its center along the stolon. Internode length, branching intensity and branching angle were 5.9 cm, 4.4 and 55.3°in the shrub, and 1.6 cm, 13.7 and 38.3°at the edge of the shrub, respectively. The clonal architecture exhibited plasticity. The internode length, branching intensity and ramet length changed with an exponential model with extention of the stolon. The stolon of S. vulgaris was monopodial branching, and each ramet should possess more than 3 adventitious roots. Ramets could take on the phenomenon of 搒elf-thinning?with clonal growth. There was a prior grade in allocation of the nutrients gained from heterogeneous space. The clonal architecture of S. vulgaris was the 搈ixed?type. 展开更多
关键词 VULGARIS clonal plant growth pattern STOLON Mu Us sandland
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Directional Filter for SAR Images Based on Nonsubsampled Contourlet Transform and Immune Clonal Selection 被引量:3
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作者 Xiao-Hui Yang Li-Cheng Jiao Deng-Feng Li 《International Journal of Automation and computing》 EI 2009年第3期245-253,共9页
A directional filter algorithm for intensity synthetic aperture radar (SAR) image based on nonsubsampled contourlet transform (NSCT) and immune clonal selection (ICS) is presented. The proposed filter mainly foc... A directional filter algorithm for intensity synthetic aperture radar (SAR) image based on nonsubsampled contourlet transform (NSCT) and immune clonal selection (ICS) is presented. The proposed filter mainly focuses on exploiting different features of edges and noises by NSCT. Furthermore, ICS strategy is introduced to optimize threshold parameter and amplify parameter adaptively. Numerical experiments on real SAR images show that there are improvements in both visual effects and objective indexes. 展开更多
关键词 Directional filter nonsubsampled contourlet transform (NSCT) immune clonal selection optimization (ICSO) syntheticaperture radar (SAR).
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Distribution patterns of clonal plants in the subnival belt of the Hengduan Mountains,SW China 被引量:2
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作者 Yongqian Gao Jinxuan Zheng +1 位作者 Xiangqun Lin Fan Du 《Plant Diversity》 SCIE CAS CSCD 2020年第5期386-392,共7页
Clonal reproduction(i.e.,production of potentially independent offspring by vegetative growth)is thought to provide plants with reproductive assurance.Thus,studying the evolution of clonal reproduction in local floras... Clonal reproduction(i.e.,production of potentially independent offspring by vegetative growth)is thought to provide plants with reproductive assurance.Thus,studying the evolution of clonal reproduction in local floras is crucial for our understanding of the adaptive mechanisms plants deploy in stressful environments such as alpine regions.In this study,we characterized clonal plant species in the subnival belt of the Hengduan Mountains(a global biodiversity hotspot with extreme environmental conditions in southwest China),in order to determine the effects of sex system,growth form,and elevational distribution on clonality.We compiled clonality data of angiosperm species belonging to 41 families in the subnival belt of the Hengduan Mountains using published information.Of the 793 species recorded in the region,47.92%(380 species)are clonal species.Both sex system and growth form had significant effects on the occurrence of clonal reproduction:unisexual species(79.79%)were more likely to be clonal than bisexual species(43.63%),and herbaceous species(51.04%)were more likely to be clonal than woody species(16.67%).Compared with non-alpine-endemic species(44.60%),alpine-endemic species(58.33%)showed a significantly higher proportion of clonal reproduction.Further logistic regression analysis showed a positive association between incidence of clonality and elevational range,indicating that species distributed at high elevations are more likely to be clonal.Furthermore,the elevational gradients in clonality were contingent on sex system or growth form.This study reveals that plants in the subnival belt of the Hengduan Mountains might optimize their probability of reproduction through clonal reproduction,a finding that adds to our growing understanding of plant's adaptations to harsh alpine environments. 展开更多
关键词 ALPINE clonal reproduction Hengduan mountains Sexual reproduction Subnival belt
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Identification of portal vein tumor thrombus with an independent clonal origin in hepatocellular carcinoma via multi-omics data analysis 被引量:1
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作者 Shupeng Liu Zaixin Zhou +5 位作者 Yin Jia Jie Xue Zhiyong Liu Kai Cheng Shuqun Cheng Shanrong Liu 《Cancer Biology & Medicine》 SCIE CAS CSCD 2019年第1期147-156,共10页
Objective: Multiple mechanisms underlying the development of portal vein tumor thrombus(PVTT) in hepatocellular carcinoma(HCC) have been reported recently. However, the origins of PVTT remain unknown. Increasing multi... Objective: Multiple mechanisms underlying the development of portal vein tumor thrombus(PVTT) in hepatocellular carcinoma(HCC) have been reported recently. However, the origins of PVTT remain unknown. Increasing multi-omics data on PVTTs in HCCs have made it possible to investigate whether PVTTs originate from the corresponding primary tumors(Ts).Methods: The clonal relationship between PVTTs and their corresponding primary Ts was investigated using datasets deposited in public databases. One DNA copy number variations dataset and three gene expression datasets were downloaded for the analyses.Clonality analysis was performed to investigate the clonal relationship between PVTTs and Ts from an individual patient.Differential gene expression analysis was applied to investigate the gene expression profiles of PVTTs and Ts.Results: One out of 19 PVTTs had no clonal relationship with its corresponding T, whereas the others did. The PVTTs with independent clonal origin showed different gene expression and enrichment in biological processes from the primary Ts. Based on the unique gene expression profiles, a gene signature including 24 genes was used to identify pairs of PVTTs and primary Ts without any clonal relationship. Validation in three datasets showed that these types of pairs of PVTTs and Ts can be identified by the 24-gene signature.Conclusions: Our findings show a direct evidence for PVTT origin and consolidate the heterogeneity of PVTTs observed in clinic.The results suggest that PVTT investigation at a molecular level is clinically necessary for diagnosis and treatment. 展开更多
关键词 HEPATOCELLULAR carcinoma portal VEIN tumor THROMBUS clonal origin COPY number variation bioinformatics
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In vitro clonal propagation of Achyranthes aspera L. and Achyranthes bidentata Blume using nodal explants 被引量:1
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作者 Wesely Edward Gnanaraj Johnson Marimuthu +1 位作者 Mohanamathi RB Kavitha Marappampalyam Subramanian 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2012年第1期1-5,共5页
Objective:To develop the reproducible in vitro propagation protocols for the medicinally important plants viz.,Achyranthes aspera(A.aspera)L.and Achyranthes bidentata(A.bidentata)Blume using nodal segments as explants... Objective:To develop the reproducible in vitro propagation protocols for the medicinally important plants viz.,Achyranthes aspera(A.aspera)L.and Achyranthes bidentata(A.bidentata)Blume using nodal segments as explants.Methods:Young shoots of A.aspera and A.bidentata were harvested and washed with running tap water and treated with 0.1%bavistin and rinsed twice with distilled water.Then the explants were surface sterilized with 0.1%(w/v)HgCl_2 solutions for I min.After rinsing with sterile distilled water for 3-4 times,nodal segments were cut into smaller segments(1 cm)and used as the explants.The explants were placed horizontally as well as vertically on solid basal Murashige and Skoog(MS)medium supplemented with 3%sucrose,0.6%(w/v)agar(HiMedia,Mumbai)and different concentration and combination of 6-benzyl amino purine(BAP),kinetin(Kin),naphthalene acetic acid(NAA)and indole acetic acid(IAA)for direct regeneration.Results:Adventitious proliferation was obtained from A.aspera and A.bidentata nodal segments inoculated on MS basal medium with 3%sucrose and augmented with BAP and Kin with varied frequency.MS medium augmented with 3.0 mg/L of BAP showed the highest percentage(93.60±0.71)of shootlets formation for A.aspera and(94.70±0.53)percentages for A.bidentata.Maximum number of shoots/explants(10.60±0.36)for A.aspera and(9.50±0.56)for A.bidentata was observed in MS medium fortified with 5.0 mg/L of BAP.For A.aspera,maximum mean length(5.50±0.34)of shootlets was obtained in MS medium augmented with 3.0 mg/L of Kin and for A.bidentata(5.40±0.61)was observed in the very same concentration.The highest percentage,maximum number of rootlets/shootlet and mean length of rootlets were observed in 1/2 MS medium supplemented with 1.0 mg/L of 1BA.Seventy percentages of plants were successfully established in polycups.Sixty eight percentages of plants were well established in the green house condition.Sixty five percentages of plants were established in the field.Conclusions:The results have shown that use of nodal buds is an alternative reproducible and dependable method for clonal propagation of A.aspera and A.bidentata.The high rate of direct shoot-root multiplication and their high rate of post-hardening survival indicate that this protocol can he easily adopted for commercial large scale cultivation. 展开更多
关键词 In vitro Plant regeneration Tissue CULTURE NODAL CULTURE Achyranthes aspera Achyranthes bidentata clonal propagation NODAL EXPLANT Reproducible MS medium SHOOTS BAP NAA IAA KINETIN NODAL segment Shootlet ROOTLET
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