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DETECTION OF PRIMARY TISSUE FAILURE POTENTIAL OF BIOPROSTHETIC HEART VALVES IN A STERILE PULSE DUPLICATOR SYSTEM
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作者 张祖仁 王一山 冯卓荣 《Medical Bulletin of Shanghai Jiaotong University》 CAS 1995年第2期91-97,共7页
This paper discusses results of anatomic analogy and transmission line model for designing a sterile pulse duplication system for bioprostheses. By simulating physiological flow and pressure pulses as well as the inpu... This paper discusses results of anatomic analogy and transmission line model for designing a sterile pulse duplication system for bioprostheses. By simulating physiological flow and pressure pulses as well as the input impedance of the human arterial system Pulsatile function testing allows us to study the hydrodynamic performances and the leaflet action of each valve. This inspection enables us to identify and reject those valves exhibiting leaflet prolapse or lazy leaflet or others believed to contribute to Primary tissue failure. Consequently, the risk of valve complications is reduced 展开更多
关键词 bioprosthetic HEART valve PRIMARY TISSUE FAILURE STERILE PULSE duplicator transmission line model
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A NEWLY DUPLICATOR FOR PULSATILE AND STEADY FLOW TESTING OF ARTIFICIAL HEART VALVE
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作者 Lu Songfang Yang Zibin +6 位作者 Peng Yi Dai Weihan Yu Xiaojun Zhu Anping(Institute of Basic Medical Sciences, CAMS,Beijing, 100005,China)Wang Jihai Zhu Xiaodong Li Xiaodong Di Yunxi(Fu Wai Hospital, CAMS,Beijing, 100037,China) 《Chinese Journal of Biomedical Engineering(English Edition)》 1996年第2期79-85,共7页
In order to go further into a question of the artificial heart valve, a pulsativeand steady flow test duplicator for the artificial heart valve (P. S. duplicator) has been developed by us. This duplicator can be used ... In order to go further into a question of the artificial heart valve, a pulsativeand steady flow test duplicator for the artificial heart valve (P. S. duplicator) has been developed by us. This duplicator can be used to measure the hydrodynamic parameters andcharacteristics of artiricial valves in vitro. So these measured valves can be assessed correctlyand precisely. The designing of the P. S. duplicator is raesonable and practical. Thus it cansatisfy the needs for the studying of various artificial valves. 展开更多
关键词 artificial HEART VALVE PULSATILE STEADY duplicator
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Adenocarcinoma originating from a colonic duplication cyst: A case report
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作者 Jeehye Lee Jung Wook Suh 《World Journal of Gastrointestinal Surgery》 2025年第4期405-411,共7页
BACKGROUND Gastrointestinal duplication is a rare congenital anomaly of the digestive tract,with colonic manifestations being particularly uncommon.Malignant transformation of colonic duplication cysts is rare,with ad... BACKGROUND Gastrointestinal duplication is a rare congenital anomaly of the digestive tract,with colonic manifestations being particularly uncommon.Malignant transformation of colonic duplication cysts is rare,with adenocarcinoma being the most frequently reported type.Herein,we report a rare case of adenocarcinoma originating from a colonic duplication cyst.CASE SUMMARY A 49-year-old woman was found to have an elevated cancer antigen 19-9 level during a routine checkup.Imaging revealed a well-defined abdominal cavity cystic mass,which was initially suspected to be an ovarian teratoma.Laparoscopic surgery revealed a duplication cyst,and pathological examination confirmed adenocarcinoma arising from the cyst.The mass within the transverse mesocolon was successfully excised by a colorectal surgeon.Immunohistochemical analysis confirmed adenocarcinoma with invasion into the muscularis propria.Postoperative endoscopy and positron emission computed tomography scan showed no signs of malignancy,except for an elevated cancer antigen 19-9 level.A multidisciplinary team recommended no further chemotherapy,advising routine follow-up for monitoring.CONCLUSION Colonic duplications,though rare,remain a differential diagnosis of unexplained abdominal masses,with complete resection being their primary treatment approach. 展开更多
关键词 Gastrointestinal duplication Colonic duplication Surgical resection ADENOCARCINOMA Malignant transformation Case report
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High-quality reference genome decoding and population evolution analysis of prickly Sechium edule
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作者 Xiaojing Wang Shaoqin Shen +3 位作者 Yanhong Fu Rui Cao Yunfeng Wei Xiaoming Song 《Horticultural Plant Journal》 2025年第2期827-838,共12页
Sechium edule(chayote)is an important vegetable crop belonging to the Cucurbitaceae family.To decipher the chayote genome,a highquality chromosome-level chayote genome was obtained by genome sequencing and bioinformat... Sechium edule(chayote)is an important vegetable crop belonging to the Cucurbitaceae family.To decipher the chayote genome,a highquality chromosome-level chayote genome was obtained by genome sequencing and bioinformatic analysis.The total length was612.91 Mb,and 25755 genes were detected in the chayote genome.The contig N50 was more than 20.01 Mb,and the scaffold N50 was over47.11 Mb.Of the genome,60.35%were composed of repetitive sequences,and 31.18%of genome sequences belonged to long-terminal repeats.A global alignment of homologous regions in chayote and other Cucurbitaceae plant genomes was constructed using grape as a reference.Based on this genome-wide and global alignment map,researchers can easily identify homologous collinear genes of the studied genomes in most Cucurbitaceae species.Twenty-five chayote accessions were divided into two subgroups based on phylogenetic tree,population structure analysis,and principal component analysis using genome re-sequencing data.The chayote genome,re-sequencing dataset,and comprehensive genomic analysis will accelerate comparative and functional genomic analysis of chayote and other Cucurbitaceae species in the future. 展开更多
关键词 Sechium edule Whole-genome duplication Divergence time Genome evolution Population structure CUCURBITACEAE
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The chromosome-scale genome of black wolfberry(Lycium ruthenicum)provides useful genomic resources for identifying genes related to anthocyanin biosynthesis and disease resistance
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作者 Gulbar Yisilam Enting Zheng +5 位作者 Chuanning Li Zhiyong Zhang Ying Su Zhenzhou Chu Pan Li Xinmin Tian 《Plant Diversity》 2025年第2期201-213,共13页
The black wolfberry(Lycium ruthenicum;2n=2x=24)is an important medicinal plant with ecological and economic value.Its fruits have numerous beneficial pharmacological activities,especially those of anthocyanins,polysac... The black wolfberry(Lycium ruthenicum;2n=2x=24)is an important medicinal plant with ecological and economic value.Its fruits have numerous beneficial pharmacological activities,especially those of anthocyanins,polysaccharides,and alkaloids,and have high nutritional value.However,the lack of available genomic resources for this species has hindered research on its medicinal and evolutionary mechanisms.In this study,we developed the telomere-to-telomere(T2T)nearly gapless genome of L.ruthenicum(2.26 Gb)by integrating PacBio HiFi,Nanopore Ultra-Long,and Hi-C technologies.The assembled genome comprised 12 chromosomes with 37,149 protein-coding genes functionally annotated.Approximately 80%of the repetitive sequences were identified,of which long terminal repeats(LTRs)were the most abundant,accounting for 73.01%.The abundance of LTRs might be the main reason for the larger genome of this species compared to that of other Lycium species.The species-specific genes of L.ruthenicum were related to defense mechanisms,salt tolerance,drought resistance,and oxidative stress,further demonstrating their superior adaptability to arid environments.Based on the assembled genome and fruit transcriptome data,we further constructed an anthocyanin biosynthesis pathway and identified 19 candidate structural genes and seven transcription factors that regulate anthocyanin biosynthesis in the fruit developmental stage of L.ruthenicum,most of which were highly expressed at a later stage in fruit development.Furthermore,154 potential disease resistance-related nucleotidebinding genes have been identified in the L.ruthenicum genome.The whole-genome and proximal,dispersed,and tandem duplication genes in the L.ruthenicum genome enriched the number of genes involved in anthocyanin synthesis and resistance-related pathways.These results provide an important genetic basis for understanding genome evolution and biosynthesis of pharmacologically active components in the Lycium genus. 展开更多
关键词 Lycium ruthenicum GENOME Anthocyanin biosynthesis Gene duplication Comparative genomics
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The Monochoria genome provides insights into the molecular mechanisms underlying floral heteranthery
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作者 Jingshan Yang Jinming Chen +3 位作者 Xiangyan He Guangxi Wang Spencer C.H.Barrett Zhizhong Li 《Journal of Genetics and Genomics》 2025年第6期826-838,共13页
Heteranthery,the occurrence of functionally and structurally distinct stamens within a flower,represents a striking example of convergent evolution among diverse animal-pollinated lineages.Although the ecological basi... Heteranthery,the occurrence of functionally and structurally distinct stamens within a flower,represents a striking example of convergent evolution among diverse animal-pollinated lineages.Although the ecological basis of this somatic polymorphism is understood,the developmental and molecular mechanisms are largely unknown.To address this knowledge gap,we selected Monochoria elata(Pontederiaceae)as our study system due to its typical heterantherous floral structure.We constructed a chromosome-level genome assembly of M.elata,conducted transcriptomic analyses and target phytohormone metabolome analysis to explore gene networks and hormones associated with heteranthery.We focused on three key stamen characteristics—colour,spatial patterning,and filament elongation—selected for their significant roles in stamen differentiation and their relevance to the functional diversity observed in heterantherous species.Our analyses suggest that gene networks involving MelLEAFY3,MADS-box,and TCP genes regulate stamen identity,with anthocyanin influencing colour,and lignin contributing to filament elongation.Additionally,variation in jasmonic acid and abscisic acid concentration between feeding and pollinating anthers appears to contribute to their morphological divergence.Our findings highlight gene networks and hormones associated with intra-floral stamen differentiation and indicate that whole genome duplications have likely facilitated the evolution of heteranthery during divergence from other Pontederiaceae without heteranthery. 展开更多
关键词 FLAVONOIDS Gene expression Heteranthery Stamen development Whole genome duplication
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Natural variation of ClCCT promoter promotes flowering and dwarfing in adlay(Coix lacryma-jobi L.)
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作者 Jieliang Bao Yanan Wang +11 位作者 Kuoshu Cui Xiangdong Li Hong Pan Chaoyuan Shi Xiang Yan Jinglin Wang Xiaotong Wang Qing Dou Xiaolong Dong Yibing Yuan Shufeng Zhou Chao Guo 《The Crop Journal》 2025年第3期942-951,共10页
The flowering time is a key trait that determines adaptation,yield and quality of crops.Adlay,a traditional cereal crop,has developed a distinctive agricultural industry in Southwest China and Southeast Asian countrie... The flowering time is a key trait that determines adaptation,yield and quality of crops.Adlay,a traditional cereal crop,has developed a distinctive agricultural industry in Southwest China and Southeast Asian countries.However,the currently planted varieties are all semi-domesticated landraces with delayed flowering and excessive height.These defects limit yield improvement per unit area and mechanized harvesting.In this study,a major QTL associated with flowering time and plant height in adlay has been mapped and identified as Cl CCT,a gene having a conserved function and regulatory pathway for inhibiting flowering time and increasing plant height in gramineous crops.Among the six identified haplotypes of Cl CCT,the haplotype with 38-bp insertion in promoter region of Cl CCT has earlier flowering time and wider geographical distribution than other haplotypes.The insertion variation,which arises from the segmental duplication of Cl CCT,can inhibit the expression level of reporter gene and has been used in breeding for early maturity and dwarfing.These research results not only reinforce our understanding of the importance of CCT domain protein in the tropical crops adapting to high-latitude environment,but also provide a validated breeding target for the early maturity and dwarfing of adlay. 展开更多
关键词 Early maturity DWARFING CCT domain Convergent selection Genome duplication event
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Laparoscopic management of gallstones in a duplicate gallbladder with double cystic ducts:A case report
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作者 Abuduniyazi Ahunayizhi Xin-Long Zhang +5 位作者 Qian Chen Hui Wang Gang Ding Sulaiman Akumuo Xue-Xin Wang Xiao-Jiao Ruan 《World Journal of Gastrointestinal Surgery》 2025年第9期455-460,共6页
BACKGROUND Duplicated gallbladder with two completely independent cystic ducts is an exceptionally rare congenital anomaly.This case report documents an example of successful laparoscopic management,adding to the limi... BACKGROUND Duplicated gallbladder with two completely independent cystic ducts is an exceptionally rare congenital anomaly.This case report documents an example of successful laparoscopic management,adding to the limited literature by highlighting the importance of accurate preoperative imaging and surgical planning.CASE SUMMARY We present the case of a 46-year-old Uyghur woman who was admitted with intermittent right upper abdominal pain accompanied by nausea and vomiting that had persisted for 1 week.Her basic blood test results,including liver function test,were normal.Preoperative ultrasound revealed an abnormal echo in the gallbladder region,suggesting a double gallbladder malformation with one chamber containing multiple stones.Computed tomography and magnetic resonance cholangiopancreatography confirmed a double gallbladder anomaly.The patient subsequently underwent successful laparoscopic cholecystectomy.During the procedure,two gallbladder chambers were identified,with each cystic duct being independently inserted into the common bile duct.Surgery was completed without complications,and postoperative pathology confirmed the presence of gallstones and chronic cholecystitis.Because of the effective preoperative assessment,the patient recovered smoothly and was discharged 3 days after surgery,reporting no discomfort during follow-up.CONCLUSION This case highlights the need for thorough evaluation of rare gallbladder anomalies;literature recommends removing both to prevent disease recurrence.We present this case to raise clinical awareness,support appropriate diagnosis,and reinforce the recommendation to remove both gallbladders to prevent recurrence of gallbladder disease. 展开更多
关键词 Duplicate gallbladder Double cystic duct GALLSTONES Laparoscopic cholecystectomy Case report
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Map-based cloning and characterization reveal that an R2R3 MYB gene confers red glume in wheat
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作者 Weiwei Mao Xiaobo Wang +15 位作者 Yongming Chen Yongfa Wang Liang Ma Xiaoming Xie Xiaojia Wu Jin Xu Yuqi Zhang Yue Zhao Xuejun Tian Weilong Guo Zhaorong Hu Mingming Xin Yingyin Yao Zhongfu Ni Qixin Sun Huiru Peng 《The Crop Journal》 2025年第3期887-899,共13页
Pigment accumulation is an important trait related to wheat domestication,but there remains a limited understanding of its molecular mechanism.The genetic control of the red glume trait by a dominant allele,Rg-B1,on 1... Pigment accumulation is an important trait related to wheat domestication,but there remains a limited understanding of its molecular mechanism.The genetic control of the red glume trait by a dominant allele,Rg-B1,on 1BS was reported in the last century,but the underlying gene and its molecular basis remained elusive.Here,we identified TraesTSP1B01G005700(G57)encoding an R2R3-MYB transcription factor(TF)as the candidate Rg-B1 gene controlling red glume color by a combination of genome-wide association study(GWAS),bulked segregant RNA-sequencing(BSR-Seq),map-based cloning,and RNAseq.The Rg-B1 locus had zero to five duplicate copies only one of which had high transcriptional activity.Genetic evidence suggested that promoter sequence variation in G57 in the glume leads to high expression of G57,resulting in the red glume phenotype.G57 could bind to the promoters of anthocyanin synthesis genes TaCHS,TaF3'H,and TaUFGT,activating their expression and contributing to anthocyanin accumulation in wheat glume.G57 also played a pivotal role in up-regulating expression of genes TaDREB1C and TaFLO2 associated with increased grain weight,thereby causing increased grain weight.Our research offers a better understanding of the molecular basis of red glume in bread wheat. 展开更多
关键词 ANTHOCYANIN Red glume color Gene duplication Triticum aestivum
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Subtotal resection of gastric duplication cysts using endoscopic submucosal dissection: A case report
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作者 Ning Zhu Meng-Yao Chen +5 位作者 Ke-Qing Li Yuan-Miao Zhang Fang-Lan Li Peng Li Jie Wu Bai-Cang Zou 《World Journal of Gastrointestinal Surgery》 2025年第10期428-433,共6页
BACKGROUND Gastric duplication cysts(GDCs)are rare congenital anomalies,and consensus guidelines for their diagnosis and management are currently lacking.We report a rare case of a GDC in a female child presenting as ... BACKGROUND Gastric duplication cysts(GDCs)are rare congenital anomalies,and consensus guidelines for their diagnosis and management are currently lacking.We report a rare case of a GDC in a female child presenting as a submucosal tumor in the gastric antrum.Subtotal resection was achieved using endoscopic submucosal dissection(ESD),resulting in complete symptom relief and pathological confirmation.This case demonstrates the therapeutic potential of ESD for intraluminal GDCs and underscores the importance of complete resection for definitive diagnosis.CASE SUMMARY A 12-year-old girl presented with abdominal distension and pain for>1 year.Gastroscopy revealed a protruding lesion approximately 30 mm in diameter in the gastric antrum.Superficial biopsies revealed moderate chronic inflammation and intestinal metaplasia.Contrast-enhanced computed tomography showed a mass protruding into the gastric lumen with homogeneous cyst wall enhancement.Endoscopic ultrasonography identified a hypoechoic mass originating from the muscularis mucosa.The patient underwent ESD for diagnosis and symptom relief.Intraoperatively,due to firm adhesion between the cyst base and the muscularis propria,selective preservation of the adherent cyst base was performed to mitigate perforation and stenosis risks.Histopathology confirmed a GDC,with cyst lumen lined by gastric-type columnar epithelium and an outer smooth muscle layer.Focal ectopic pancreatic tissues were identified.The patient recovered without complications and remained asymptomatic during 6-month follow-up.Repeat gastroscopy showed the residual cyst wall conforming to antral mucosa,with no recurrence.CONCLUSION Subtotal resection of GDCs using ESD demonstrates a favorable prognosis. 展开更多
关键词 Gastric duplication cysts Endoscopic submucosal dissection Endoscopic ultrasound Subtotal resection Case report
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Amalgamation of Classical and Large Language Models for Duplicate Bug Detection:A Comparative Study
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作者 Sai Venkata Akhil Ammu Sukhjit Singh Sehra +1 位作者 Sumeet Kaur Sehra Jaiteg Singh 《Computers, Materials & Continua》 2025年第4期435-453,共19页
Duplicate bug reporting is a critical problem in the software repositories’mining area.Duplicate bug reports can lead to redundant efforts,wasted resources,and delayed software releases.Thus,their accurate identifica... Duplicate bug reporting is a critical problem in the software repositories’mining area.Duplicate bug reports can lead to redundant efforts,wasted resources,and delayed software releases.Thus,their accurate identification is essential for streamlining the bug triage process mining area.Several researchers have explored classical information retrieval,natural language processing,text and data mining,and machine learning approaches.The emergence of large language models(LLMs)(ChatGPT and Huggingface)has presented a new line of models for semantic textual similarity(STS).Although LLMs have shown remarkable advancements,there remains a need for longitudinal studies to determine whether performance improvements are due to the scale of the models or the unique embeddings they produce compared to classical encoding models.This study systematically investigates this issue by comparing classical word embedding techniques against LLM-based embeddings for duplicate bug detection.In this study,we have proposed an amalgamation of models to detect duplicate bug reports using textual and non-textual information about bug reports.The empirical evaluation has been performed on the open-source datasets and evaluated based on established metrics using the mean reciprocal rank(MRR),mean average precision(MAP),and recall rate.The experimental results have shown that combined LLMs can outperform(recall-rate@k 68%–74%)other individual=models for duplicate bug detection.These findings highlight the effectiveness of amalgamating multiple techniques in improving the duplicate bug report detection accuracy. 展开更多
关键词 Duplicate bug detection large language models information retrieval
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Electrophoretic Analysis of Isozymes and Discussion about Species Differentiation in Three Species of Genus Gymnocypris 被引量:15
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作者 陈毅峰 何德奎 陈宜瑜 《Zoological Research》 CAS CSCD 北大核心 2001年第1期9-19,共11页
By using the method of electrophoresis,three isozymes (lactate dehydrogenase,malate dehydrogenase and esterase) of three species of genus Gymnocypris were described and analyzed from North Tibet in this paper. The... By using the method of electrophoresis,three isozymes (lactate dehydrogenase,malate dehydrogenase and esterase) of three species of genus Gymnocypris were described and analyzed from North Tibet in this paper. The results showed that all three isozymes presented interspecific difference and distinct differentiation among individuals in the same population,and there was no electrophorectic difference between males and females. Analysis of relationships among three naked carps indicated a high degree of similarity between G. selincuoensis and G. cuoensis ,whereas low degree between G. selincuoensis and G. namensis . Furthermore,three isozymes presented expression of null alleles,and the duplicate genes of LDH A 2,LDH B 2,s MDH A 2 and m MDH B 2 also expressed in some individuals. Compared to other tetraploid fishes,three naked carps retained more functional duplicate genes and null alleles. This suggests fishes of genus Gymnocypris are at the early stage of evolution after polyploidization than that of fishes of Catostomidae,it directly related to the later time of schizothoracine fishes originate as well as severe environment. 展开更多
关键词 Naked carps ( Gymnocypris ) North Tibet Isozyme electrophoresis Duplicate gene Null allele Species differentiation
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Segmental Duplications Are Common in Rice Genome 被引量:1
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作者 王石平 刘克德 张启发 《Acta Botanica Sinica》 CSCD 2000年第11期1150-1155,共6页
Segmental duplications on rice (Oryza sativa L.) chromosomes 8, 9, 11, and 12 were studied by examining the distributions of sequences resolved by 13 probes detecting multiple copies of DNA sequences. Four of the hyb... Segmental duplications on rice (Oryza sativa L.) chromosomes 8, 9, 11, and 12 were studied by examining the distributions of sequences resolved by 13 probes detecting multiple copies of DNA sequences. Four of the hybridization bands detected by a repetitive sequence probe, rTRS, were mapped to the ends of all the four chromosomes. Two or three of the bands detected by each of the other 12 probes were also mapped to different chromosomes. The bands detected by the same probe usually occurred in similar locations of different chromosomes. Loci detected by different DNA probes were often similarly arranged on different chromosomes. Chromosomes 8 and 9 showed colinearity of marker loci arrangement indicating a possible common origin. A segment on chromosome 9 was also very similar to the previously reported duplicated fragments on the ends of chromosomes 11 and 12 which were also detected in this study, indicating a likely common origin. Moreover, the various degrees of distributional similarity of the segments suggest a complex relationship among the chromosomes in the evolution of the rice genome. These results support the proposition that chromosome duplication and diversification may be a mechanism for the origin and evolution of the chromosomes in the rice genome. 展开更多
关键词 chromosomal duplication repetitive sequence molecular mapping EVOLUTION r€
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小儿腹膜后肠重复畸形一例 被引量:1
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作者 王素雅 高剑波 李磊 《临床放射学杂志》 CSCD 北大核心 2016年第7期1139-1139,共1页
患儿男,10岁。10天前无诱因出现上腹部疼痛,可自行缓解,反复发作,无无恶心、呕吐、腹痛、腹胀、腹泻、黑便等临床症状。体检未见异常。CT检查:平扫示左侧腹膜后不规则状囊性占位,单房,边界尚清,壁厚(图1),增强后囊壁可见中度强化,囊... 患儿男,10岁。10天前无诱因出现上腹部疼痛,可自行缓解,反复发作,无无恶心、呕吐、腹痛、腹胀、腹泻、黑便等临床症状。体检未见异常。CT检查:平扫示左侧腹膜后不规则状囊性占位,单房,边界尚清,壁厚(图1),增强后囊壁可见中度强化,囊性成分未见强化(图2、3)。术中见病变位于腹膜后,外有包膜,紧邻胰尾部及降结肠,无法判断病变起源。术后病理:肠重复畸形(图4)。 展开更多
关键词 肠重复畸形 消化道重复 侧腹膜 不规则状 腹部疼痛 囊壁 胰尾 DUPLICATION 临床症状 平扫
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Hydrodynamics of a Newly China-Made Jiuling Bileaflet Heart Valve Prostheses 被引量:8
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作者 CHU Yin ping 1,CHEN Ru kun 2,FAN Yu bo 3 , PU Fang 31 Department of Thoracic & Cardiovascular Surgery Second Hospital Affiliated Shanxi Medical University, Taiyuan 030001,China 2 Second Affiliated Hospital of Zhejiang University Medical 《Chinese Journal of Biomedical Engineering(English Edition)》 2000年第4期168-179,共12页
Jiuling bileaflet prosthetic heart valve is manufactured in compliance with the national standard of P.R.C. GB12279 90. This mechanical heart valve substitute is constructed entirely of solid low temperature pyrolytic... Jiuling bileaflet prosthetic heart valve is manufactured in compliance with the national standard of P.R.C. GB12279 90. This mechanical heart valve substitute is constructed entirely of solid low temperature pyrolytic carbon. There is no graphite substrate within the leaflets or orifice. This prosthesis presents with satisfactory histocompatibility and induces little hemocoagulation around it. Objective: This study aimed to assess the hydrodynamic function of the newly China made Jiuling bileaflet heart valve prostheses. Methods: Jiuling valve has been tested in a pulsatile flow simulator in the aortic position. The testing condition was set at the pulsatile frequency of 55, 75, and 100 beats/min and a constant cardiac output of 4 L/min. The mean pressure differences, leakage volumes and closing volumes across each valve, and the effective orifice areas have been analyzed. Results: The Jiuling heart valves prosthesis had the lowest pressure difference at any given tissue annulus diameter. The mean pressure difference of all the Jiuling valves decreases with increasing the tissue annulus diameter or pulse frequency, and is in the range of below 10 mmHg. CarboMedics (CarboMedics, Inc., Austin, Tex.) is similar to that of the 21 mm and 23 mm Jiuling heart valves at the given pulse rate under 4 L/min. C L tilting disc valve (Lanzhou CarboMedics Inc., China) is similar to that of the 23 mm Jiuling heart valve. The effective orifice area of the Jiuling mechanical valve increases with increasing the tissue annulus diameter or pulse frequency. CarboMedics and C L tilting disc valve is similar to that of the 21 mm and 23 mm Jiuling heart valves. The Closing volume of the Jiuling prosthetic cardiac valves increases with increasing the tissue annulus diameter, but decreases with increasing the pulse frequency, and is in the range of below 11% (normalized by stroke volume). CarboMedics is below 16.5% of stroke volume; and C L tilting disc valve is below 7.5%. The leakage volume of the Jiuling prosthetic cardiac valves increases with increasing the tissue annulus diameter, but decreases with increasing the pulse frequency, and are in the range of below 28.9% (normalized by stroke volume). The leakage volume of CarboMedics is higher than that of the same sized 25 mm Jiuling valve, and the C L tilting disc valve is also higher than that of Jiuling valve at 4 L/min. Conclusion: For a given tissue diameter, the Jiuling valve showed significantly better hemodynamic characteristics. The material used in the construction is biocompatible, durable, and thromboresistant. The design permits light weight, low profile, and high ratio of flow area to tissue annulus diameter. 展开更多
关键词 In VITRO PULSATILE duplicator HEART VALVE SUBSTITUTE Jiuling HEART VALVE prosthesis
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System of twice-gathering information and research of information fingerprint HashTrie
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作者 沈阳 朱婵元 李舒晨 《Journal of Southeast University(English Edition)》 EI CAS 2008年第3期381-384,共4页
This paper presents a twice-gathering information interactive system prototype of e-government based on the condition that the Intranet and the Extranet are physical isolated.Users in the Extranet can gather links of ... This paper presents a twice-gathering information interactive system prototype of e-government based on the condition that the Intranet and the Extranet are physical isolated.Users in the Extranet can gather links of the latest related information from client software which is previously collected by web alert in the Internet.Finally,through ferry-type transport devices,information is browsed by users in the Intranet,and it is transported to a storage device and synchronized with the web platform in the Intranet.During information gathering in the Extranet and data synchronization in the Intranet,it is essential to avoid repeated gathering and copying by means of comparing the extracted information fingerprints gathered from the web pages.This prototype uses HashTrie to store information fingerprints.During testing,the structure based on HashTrie is 2.28 times faster than the Darts(double array Trie)which is the fastest structure in the existing applied patent.The existing 12 types of high speed Hash functions serving for HashTrie are also implemented.When the dictionary content is larger than 5×105 words,the PJWHash or the SuperFastHush function can be adopted;when the dictionary content is 105 words, CalcStrCR32 and ELFHash functions can be adopted. 展开更多
关键词 physical isolation twice-gathering duplicated web pages elimination information fingerprint HashTrie
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Duplicate identification model for deep web 被引量:4
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作者 刘丽楠 寇月 +2 位作者 孙高尚 申德荣 于戈 《Journal of Southeast University(English Edition)》 EI CAS 2008年第3期315-317,共3页
A duplicate identification model is presented to deal with semi-structured or unstructured data extracted from multiple data sources in the deep web.First,the extracted data is generated to the entity records in the d... A duplicate identification model is presented to deal with semi-structured or unstructured data extracted from multiple data sources in the deep web.First,the extracted data is generated to the entity records in the data preprocessing module,and then,in the heterogeneous records processing module it calculates the similarity degree of the entity records to obtain the duplicate records based on the weights calculated in the homogeneous records processing module.Unlike traditional methods,the proposed approach is implemented without schema matching in advance.And multiple estimators with selective algorithms are adopted to reach a better matching efficiency.The experimental results show that the duplicate identification model is feasible and efficient. 展开更多
关键词 duplicate records deep web data cleaning semi-structured data
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