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1.
Artigo em Chinês | WPRIM | ID: wpr-1023770

RESUMO

Objective To explore the dynamic process of fluid-structure interaction(FSI)between venous blood and valves and the physiological mechanism that guarantees unidirectional blood reflux back to the heart.Methods A three-dimensional(3D)numerical model of the venous system was established using the immersed boundary/finite element method.In the simulation,information from medical images of human lower-extremity veins and the anatomical structure and size of the bovine great saphenous vein were applied.Moreover,a hyperelastic constitutive model was used to describe the incompressible,nonlinear,and hyperelastic mechanical responses of the venous valve under physiological conditions.Results The simulations visualized the process of venous blood transport and the function of venous valves in preventing reflux.The periodic characteristics of venous valve motion and blood flow were reproduced,and important physiological data during the entire cardiac cycle were discussed and quantified,including the pressure,velocity,and flow rate of venous blood;opening area of the venous valve;and stress and strain distributions on the valve surface.Conclusions The 3D FSI model numerically reproduces the physiological dynamic process within veins and potentially provides important references and guidance for revealing the pathological mechanism of venous diseases.

2.
Acta Anatomica Sinica ; (6): 73-81, 2024.
Artigo em Chinês | WPRIM | ID: wpr-1015147

RESUMO

Objective Hippocampal atrophy is a clinically important marker for the diagnosis of many psychiatric disorders such as Alzheimer’s disease‚ so accurate segmentation of the hippocampus is an important scientific issue. With the development of deep learning‚ a large number of advanced automatic segmentation method have been proposed. However‚ 3D hippocampal segmentation is still challenging due to the effects of various noises in MRI and unclear boundaries between various classes of the hippocampus. Therefore‚ the aim of this paper is to propose new method to segment the hippocampal head‚ body‚ and tail more accurately. Methods To overcome these challenges‚ this paper proposed two strategies. One was the spatial and frequency domain features adaptive fusion strategy‚ which reduced the influence of noise on feature extraction by automatically selecting the appropriate frequency combination through fast Fourier transform and convolution. The other was an inter-class boundary region enhancement strategy‚ which allowed the network to focus on learning the boundary regions by weighting the loss function of the boundary regions between each class to achieve the goal of pinpointing the boundaries and regulating the size of the hippocampal head‚ body and tail. Results Experiments performed on a 50-case teenager brain MRI dataset show that our method achieves state-of-the-art hippocampal segmentation. Hippocampal head‚ body and tail had been improved compared to the existing method. Ablation experiments demonstrated the effectiveness of our two proposed strategies‚ and we also validated that the network had a strong generalization ability on a 260-case Task04_Hippocampus dataset. It was shown that the method proposed in this paper could be used in more hippocampal segmentation scenarios. Conclusion The method proposed in this paper can help clinicians to observe hippocampal atrophy more clearly and accomplish more accurate diagnosis and follow-up of the condition.

3.
Artigo em Chinês | WPRIM | ID: wpr-1025097

RESUMO

Based on the development history that the modern medicine and laboratory animal science have long been hindered by animal welfare groups and animal-rights activists in Western countries,and considering the relevant circumstance in China,the author appeals and recommends that the laboratory animal practitioners and biomedical researchers,the scientific community in China should recognize and identify the boundaries of our professional activities.Firstly,do not participate in the activity related to so called"World(Lab)Animal Day"that is said in some Chinese websites,to originate from NAVS,an antivivisection society Ltd.,London.Secondly,do not participate in the activity related to so called"animal memorial stone"that was originated in Japan.These movements have nothing to do with biomedicine and laboratory animal sciences,and fundamentally are antiscientific and are incompatible to traditional Chinese culture.Thirdly,distinguish the standpoints of laboratory animal science from various viewpoints of animal welfare/rights activists,promote scientific management of the institutional animal care and use for better supporting biomedical research in China.

4.
Artigo em Chinês | WPRIM | ID: wpr-1026194

RESUMO

The study explores the thermal dose of experimental animals exposed in electromagnetic field.The simulation environment containing electromagnetic and thermal doses is established based on the bioheat equation and the three-dimensional rat model,and the effects of specific absorption rate,metabolic rate and boundary condition on temperature distribution and variation are assessed.The result shows that the core temperature rises with increasing whole body average specific absorption rate(WBASAR).At WBASAR of 4 W/kg,the midbrain and testes have higher specific absorption rates due to the skin effect,resulting in a more significant temperature rise in organ tissues than in the core;and at WBASAR of 0.4 W/kg,the temperature variation of the shallow organs caused by the sudden changes of metabolic and external environment reaches 1℃,which is much larger than that of the core.The experiment demonstrates target organs such as the head and testicles as critical subjects in thermal dose assessment.The experimental conditions should be regulated to reduce the effects of metabolic rate and boundary condition on thermal dose.The study has guiding significance for bioelectromagnetic experimental design and effect evaluation on thermal dose.

5.
Chinese Journal of Biotechnology ; (12): 2914-2925, 2023.
Artigo em Chinês | WPRIM | ID: wpr-981240

RESUMO

Pellionia scabra belongs to the genus Pellionia in the family of Urticaceae, and is a high-quality wild vegetables with high nutritional value. In this study, high-throughput techniques were used to sequence, assemble and annotate the chloroplast genome. We also analyzed its structure, and construct the phylogenetic trees from the P. scabra to further study the chloroplast genome characteristics. The results showed that the chloroplast genome size was 153 220 bp, and the GC content was 36.4%, which belonged to the typical tetrad structure in P. scabra. The chloroplast genome encodes 130 genes, including 85 protein-coding genes, 37 tRNA genes, and 8 rRNA genes in P. scabra. Among them, 15 genes contained 1 intron, 2 genes contained 2 introns, and rps12 had trans-splicing, respectively. In P. scabra, chloroplast genomes could be divided into four categories, including 43 photosynthesis, 64 self-replication, other 7 coding proteins, and 4 unknown functions. A total of 51 073 codons were detected in the chloroplast genome, among which the codon encoding leucine (Leu) accounted for the largest proportion, and the codon preferred to use A and U bases. There were 72 simple sequence repeats (SSRs) in the chloroplast genome of P. scabra, containing 58 single nucleotides, 12 dinucleotides, 1 trinucleotide, and 1 tetranucleotide. The ycf1 gene expansion was present at the IRb/SSC boundary. The phylogenetic trees showed that P. scabra (OL800583) was most closely related to Elatostema stewardii (MZ292972), Elatostema dissectum (MK227819) and Elatostema laevissimum var. laevissimum (MN189961). Taken together, our results provide worthwhile information for understanding the identification, genetic evolution, and genomics research of P. scabra species.


Assuntos
Filogenia , Genoma de Cloroplastos/genética , Genômica , Cloroplastos/genética , Códon , Urticaceae/genética
6.
Journal of Medical Biomechanics ; (6): E123-E128, 2023.
Artigo em Chinês | WPRIM | ID: wpr-987924

RESUMO

Objective To study the motion and deformation of red blood cells ( RBCs) with different mechanical properties in capillaries,and make analysis on the associated hemorheological parameters. Methods The RBC was modeled as a hyper elastic membrane using Skalak model. The fluid was solved using a two-order difference scheme with the membrane mechanics treated by the immersed method. The pathological viscosity ratio λ= 5 was considered. Results The steady deformation of RBCs with different membrane stiffness in the capillary was obtained. With membrane stiffness increasing, the cell transformed from axisymmetric shapes to non-axisymmetric shapes. With capillary number increasing, the deformability of RBCs weakened and the flow resistance increased. Conclusions With stiffening of cell membrane, the non-axisymmetric cell shape appears and the flow resistance increases. Therefore, in diseases involved stiffening RBCs, the stiffened RBCs can cause the blockage of capillaries and hypoxia in surrounding tissues.

7.
Artigo em Chinês | WPRIM | ID: wpr-1022931

RESUMO

Objective To explore the dosimetric effects of a self-developed planning mode of boundary range scattering dose(BRSD)on Cyberknife treatment of lung cancer brain metastases.Methods The positioning images of 15 patients with lung cancer brain metastases treated in the radiotherapy department of some institution from January 1,2021 to December 31,2021 were selected and introduced into Cyberknife Multiplan 4.0.3 treatment planning system.A fractionated stereotactic radiotherapy(FSRT)plan(as the FSRT planning group)and a BRSD plan(as the BRSD planning group)were developed for each patient.The FSRT planning group developed a plan for the planning target volume(PTV)in the conventional way,so that V100 covered more than 95%of the PTV;the BRSD planning group prepared a plan for the gross tumor volume(GTV)with the same parameter conditions as the FSRT planning group and the prescription dose was normalized to the PTV so that V100 covered more than 95%of the PTV.The dosimetric parameters of the target area and normal tissue of the 2 groups were compared by dose-volume histograms and isodose curves.Statistical analysis was performed using SPSS 24.0 software.Results The D98,Dmax and Dmean in the target area of the BRSD planning group were significantly higher than those of the FSRT planning group,and the differences were statistically significant(P<0.05);the differences in the conformity index,dose gradient index,and Dmean,V30,V24 and D3cc in normal tissue of the 2 groups were not statistically significant(P>0.05);the BRSD planning group gained a denser dose distribution when compared with the FSRT planning group.Conclusion The BRSD planning mode gains significant dosimetric advantage by enhancing the absorbed dose to the target area without increasing or decreasing the dose to normal tissue.

8.
Artigo em Chinês | WPRIM | ID: wpr-956173

RESUMO

In the systemic perspective, family is a system capable of self-organization, which possesses enough resources and ability to solve its own problems. To promote family health, the systemic therapists are required to consider each family member’s opinions and construction to certain problems, and assist them to discover and activate their own resources as well. Promoting family health also requires members to actively develop a sharing pattern within the family, exert the positive role of family rules, develop an authoritative parenting style so as to promote the mental health of children. Family members should ensure the clear and open boundaries between different subsystems, and maintain the stability of subsystem of the husband and wife especially. Furthermore, family members in different subsystems should make reasonable trade-offs and choices corresponding to different situations in order to both minimize conflicts and maintain the satisfying function of the family system. A healthy and ideal intimate relationship is interpreted from the systemic perspective of " evolvable, changeable, associative" on the core of " intimacy, passion and commitment" . The relationship will enhance partners' personal growth, in which the partners can not only examine its dynamic variations together but also deepen the understanding and acceptance of each other under the circumstances of bilateral original families and living environments. In addition, a healthy conjugal relationship has higher requirements such as " kinship" , commitment to two families of the couple and the children, and balancing the benefits between core family and original family.

9.
Acta Pharmaceutica Sinica ; (12): 2224-2233, 2022.
Artigo em Chinês | WPRIM | ID: wpr-936584

RESUMO

italic>Cirsium souliei (Asteraceae) is a perennial medicinal herb of Cirsium with important medicinal and ecological values. Here, we sequenced the complete chloroplast (cp) genome of C. souliei based on high-throughput sequencing technology, then assembled and annotated it, and analysed the structure and characteristics of the cp genome. The result indicated that the cp genome of C. souliei was a typical quadripartite circular structure of 152 470 bp in length, and GC content was 37.7%. The cp genome of C. souliei encoded 134 genes, including 89 protein-coding genes, 37 tRNA genes and 8 rRNA genes. Meanwhile, we detected 188 simple sequence repeats (SSR) loci in the cp genome, which were mainly composed of mononucleotide repeats. Codon bias analysis showed that leucine (Leu) was the highest amino acids with frequency (10.51%), and there were 30 codons with the value of relative synonymous codon usage (RSCU) above one, of which mostly ended with A/U. Additionally, the result from phylogenetic analysis based on 46 cp genomes of Carduoideae showed that C. souliei and C. vulgare were sister species, and had the closest relationship with 100% bootstrap within Cirsium. This study provides theoretical basis for future studying genetic diversity, population genetic structure, systematics and evolution, and speciation mechanism.

10.
Chinese Journal of Biotechnology ; (12): 328-342, 2022.
Artigo em Chinês | WPRIM | ID: wpr-927714

RESUMO

Docynia longiunguis is a plant uniquely present in China and is of high edible and medicinal value. The analysis of its chloroplast genome will help clarify the phylogenetic relationship among Docynia and facilitate the development and utilization of D. longiunguis resources. Based on the alignment of chloroplast genome sequences of related species, the phylogeny and codon preference were analyzed. The total length of D. longiunguis chloroplast genome sequence was 158 914 bp (GenBank accession number is MW367027), with an average GC content of 36.7%. The length of the large single-copy (LSC), the small single-copy (SSC), and inverted repeats (IRs) are 87 020 bp, 19 156 bp, and 26 369 bp, respectively. A total of 102 functional genes were annotated, including 72 protein-coding genes, 26 tRNA genes, and 4 rRNA genes. The best model for constructing phylogenetic tree was TVM+F+R2. D. longiunguis and Docynia indica were clustered into a single group, while Docynia and Malus were clustered into a single group. Comparison of the chloroplast genome sequences of D. longiunguis and its five related species revealed that trnY (GUA)-psbD, ndhC-trnV (UAC), accD-psaI, psbZ-trnfM (CAU), ndhF-trnL gene regions varied greatly. The nucleic acid diversity analysis showed that there were 11 high variation areas with nucleotide variability > 0.01, all were located in the LSC and SSC regions. Except for D. longiunguis, the trnH genes in other sequences were located at the IRs/LSC junction and did not cross the boundary. Codon preference analysis showed that D. longiunguis chloroplast genome has the largest number of isoleucine (Ile) codons, up to 1 205. D. longiunguis has the closest genetic relationship with Malus baccata, Malus sieboldii, Malus hupehensis and Chaenomeles sinensis. Its chloroplast genome codon prefers to end with A/T. The chloroplast genome of D. longiunguis and other Rosaceae chloroplast genomes showed great differences in gene distribution in four boundary regions, while relatively small differences from the chloroplast genomes of Docynia delavayi and D. indica of the same genus were observed. The genome annotation, phylogenetic analysis and sequence alignment of chloroplast genome of D. longiunguis may facilitate the identification, development and utilization of this species.


Assuntos
Uso do Códon , Genoma de Cloroplastos , Genômica , Filogenia , Rosaceae
11.
Acta Pharmaceutica Sinica B ; (6): 2640-2657, 2022.
Artigo em Inglês | WPRIM | ID: wpr-939932

RESUMO

Accurately delineating tumor boundaries is key to predicting survival rates of cancer patients and assessing response of tumor microenvironment to various therapeutic techniques such as chemotherapy and radiotherapy. This review discusses various strategies that have been deployed to accurately delineate tumor boundaries with particular emphasis on the potential of chemotherapeutic nanomaterials in tumor boundary delineation. It also compiles the types of tumors that have been successfully delineated by currently available strategies. Finally, the challenges that still abound in accurate tumor boundary delineation are presented alongside possible perspective strategies to either ameliorate or solve the problems. It is expected that the information communicated herein will form the first compendious baseline information on tumor boundary delineation with chemotherapeutic nanomaterials and provide useful insights into future possible paths to advancing current available tumor boundary delineation approaches to achieve efficacious tumor therapy.

12.
Artigo em Chinês | WPRIM | ID: wpr-1004089

RESUMO

【Objective】 To identify the key factors that regulate the physical vacuum stirring deoxygenation process of bovine hemoglobin and evaluate the stabilities of polyHb solution with different oxygenation degree. 【Methods】 The effects of several factors including gas liquid specific phase boundary area, pH values and polyHb concentrations on deoxygenation process were investigated through monitoring the oxygen saturation of polyHb solution. Furthermore, the MetHb contents of the studied polyHb solutions were measured at regular intervals during the experiments to evaluate the molecular stability of the polyHb through monitoring the oxidation degrees of the experimental Hb solutions under the mimic pasteurevirus inactivation conditions. 【Results】 The results showed that the more gas liquid specific phase boundary area could accelerate deoxygenation rate, the better deoxygenation results could be yielded. On the other hand, lower pH value could promote the deoxygenation process of the polyHb solution due to the decreasing of oxygen affinity of the polyhemoglobin molecules. Furthermore, results of investigation about the Hb concentration presented that Hb concentration had no remarkable effects on the deoxygenation of polyHb. In addition, the results from the stability experiments presented that higher degree of deoxygenation could decrease the oxidation process and thus increase the heat tolerance of the polyhemoglobin. 【Conclusion】 The deoxygenation of polyhemglonbin could improve the stability of the polyhemoglobin and the deoxygenation process could be regulated by changing the gas liquid specific phase boundary area and oxygen affinity. This study could provide reference and preliminary basis for the industrialization and development of HBOCs in the future.

13.
Artigo em Chinês | WPRIM | ID: wpr-912587

RESUMO

Objective:Constructing a scientific research performance evaluation index system based on the departments of a tertiary hospital in Xinjiang.Methods:Delphi method and the boundary value method are used to establish the scientific research performance evaluation indicators of the hospital clinical departments, then the analytic hierarchy process is used to determine the weights of indicators at all levels.Results:A scientific research performance evaluation index system of a tertiary hospital in Xinjiang was set up, which including 3 first-level indicators, 14 second-level indicators, and 49 third-level indicators.Conclusions:The departmental scientific research performance evaluation index system established has reasonable scientificity, objectivity and feasibility, and it can be used as a reference for the evaluation of scientific research performance of departments in the tertiary hospitals.

14.
Neuroscience Bulletin ; (6): 1583-1594, 2021.
Artigo em Inglês | WPRIM | ID: wpr-922637

RESUMO

It is widely acknowledged that holistic processing is a key characteristic of face perception. Although holistic processing implies the automatic integration of face parts, it is unclear whether such processing requires the awareness of face parts. Here, we investigated the interactions between visible face parts and face parts rendered invisible using continuous flash suppression (CFS). In the first experiment with the upper half-face visible and the lower half-face invisible, the results showed that perceived face identity was influenced by the invisible lower half-face, suggesting that integration occurs between the visible and invisible face parts, a variant of the "composite face effect". In the second experiment, we investigated the influence of visible face parts on the processing of invisible face parts, as measured by the time it took for the invisible parts to break out from CFS. The results showed a visible-to-invisible facilitation effect, that the aligned invisible face parts broke through CFS faster than when the visible and invisible face parts were misaligned. Visible eyes had a stronger influence on the invisible nose/mouth than the other way around. Such facilitation of processing from visible to invisible parts was also found when Chinese characters were used as stimuli. These results show that information integration occurs across the consciousness boundary.


Assuntos
Conscientização , Estado de Consciência , Olho , Face , Reconhecimento Facial , Estimulação Luminosa
15.
Chinese Journal of Lung Cancer ; (12): 756-763, 2021.
Artigo em Chinês | WPRIM | ID: wpr-922143

RESUMO

BACKGROUND@#Segmentectomy has gradually become one of the standard surgical methods for small pulmonary nodules with early lung cancer on imaging. This study aimed to investigate the perioperative outcomes of patients who underwent uniport video-assisted thoracoscopic surgery (VATS) segmentectomy for identifying the intersegmental boundary line (IBL) by the near-infrared fluorescence imaging with intravenous indocyanine green (ICG) method or the modified inflation-deflation (MID) method and assess the feasibility and effectiveness of the ICG fluorescence (ICGF)-based method.@*METHODS@#We retrospectively analyzed the perioperative data in total 198 consecutive patients who underwent uniport VATS segmentectomy between February 2018 and August 2020. With the guidance of preoperative intelligent/interactive qualitative and quantitative analysis-three dimensional (IQQA-3D), the targeted segment structures could be precisely identified and dissected, and then the IBL was confirmed by ICGF-based method or MID method. Clinical effectiveness and postoperative complications of the two methods were evaluated.@*RESULTS@#An IBL was visible in 98% of patients by the ICGF-based group, even with the low-doses of ICG. The ICGF-based group was significantly associated with the shorter IBL clear presentation time [(23.59±4.47) s vs (1,026.80±318.34) s] (P0.05).@*CONCLUSIONS@#The ICGF-based method could highly accurately identify the IBL and make anatomical segmentectomy easier and faster, and therefore has the potential to be a feasible and effective technique to facilitate the quality of uniport VATS segmentectomy.


Assuntos
Humanos , Estudos de Viabilidade , Verde de Indocianina , Transporte de Íons , Neoplasias Pulmonares/cirurgia , Pneumonectomia , Complicações Pós-Operatórias , Estudos Retrospectivos , Cirurgia Torácica Vídeoassistida
16.
Neuroscience Bulletin ; (6): 1583-1594, 2021.
Artigo em Chinês | WPRIM | ID: wpr-951937

RESUMO

It is widely acknowledged that holistic processing is a key characteristic of face perception. Although holistic processing implies the automatic integration of face parts, it is unclear whether such processing requires the awareness of face parts. Here, we investigated the interactions between visible face parts and face parts rendered invisible using continuous flash suppression (CFS). In the first experiment with the upper half-face visible and the lower half-face invisible, the results showed that perceived face identity was influenced by the invisible lower half-face, suggesting that integration occurs between the visible and invisible face parts, a variant of the “composite face effect”. In the second experiment, we investigated the influence of visible face parts on the processing of invisible face parts, as measured by the time it took for the invisible parts to break out from CFS. The results showed a visible-to-invisible facilitation effect, that the aligned invisible face parts broke through CFS faster than when the visible and invisible face parts were misaligned. Visible eyes had a stronger influence on the invisible nose/mouth than the other way around. Such facilitation of processing from visible to invisible parts was also found when Chinese characters were used as stimuli. These results show that information integration occurs across the consciousness boundary.

17.
Artigo em Chinês | WPRIM | ID: wpr-910513

RESUMO

Objective:To analyze the influence of tracking error of Xsight lung tracking system caused by cardiac beating.Methods:48 patients with lung tumors adjacent to the heart were enrolled into this study. The tumor movement curves were collected by the Xsight lung tracking system and recorded in the treatment log files during the Cyberknife treatment process. The curves were subject to filtering analysis and the respiratory motion of < 1 Hz and the cardiac beating motion of > 1 Hz were separated. According to the filtering results, the patient treatment tracking data were divided into two groups based on whether the cardiac beating wave of >1 Hz existed. The tracking errors were statistically compared between two groups based on the X-ray imaging data collected by Xsight lung tracking system during treatment.Results:For the fractionation with cardiac beat information, the tracking errors of the patient′s related models were (1.45 ± 0.99), (0.46 ± 0.21) and (0.70 ± 0.54) mm in the left-right, superior-inferior and anterior-posterior direction, respectively. For the fractionation without cardiac beat information, the tracking errors of the patient′s related models were (1.52 ± 1.17), (0.63 ± 0.37) and (1.07 ± 0.62) mm in the left-right, superior-inferior and anterior-posterior direction, respectively. The tracking errors in the superior-inferior and anterior-posterior direction of patients with accurate cardiac beat models were 28.34% and 34.86% less than those of their counterparts without accurate cardiac beat models and there was significant difference (both P<0.05). Conclusion:The tracking accuracy of Xsight lung tracking system will be significantly improved if the cardiac beat model is accurately established.

18.
Acta amaz ; 50(1): 80-89, jan. - mar. 2020.
Artigo em Inglês | LILACS | ID: biblio-1118768

RESUMO

In this study, the erosion of the nocturnal boundary layer (NBL) was analyzed in the central Amazon during the dry season of 2014, using data from the GoAmazon 2014/5 Project and high-resolution model outputs (PArallelized Les Model - PALM). The dataset consisted of in situ (radiosonde) and remote sensing instruments measurements (Ceilometer, Lidar, Wind Profiler, microwave radiometer, and SODAR). The results showed that the NBL erosion occurred, on average, two hours after sunrise (06:00 local time), and the sensible heat flux provided more than 50% of the sensible heating necessary for the erosion process to occur. After the erosion, the convective phase developed quickly (175.2 m h-1). The measurements of the remote sensors showed that the Ceilometer, in general, presented satisfactory results in relation to the radiosondes for measuring the height of the planetary boundary layer. The PALM simulations represented well the NBL erosion, with a small underestimation (≈ 20 m) at the beginning of this phase. In the final phase of NBL erosion and in the initial stage of the development of the convective boundary layer (CBL), the model presented satisfactory results, with heights of CBL ranging from 800 m to 1,650 m, respectively. (AU)


Assuntos
Erosão , Ecossistema Amazônico , Estação Seca
19.
Artigo em Chinês | WPRIM | ID: wpr-872902

RESUMO

Objective:To find the natural environmental boundary of the origin of the authentic Ligusticum chuanxiong by analyzing the distribution characteristics of soil elements in the traditional geo-authentic area and the southern continuous expanding areas along the same longitude. Method:The contents of 24 elements both in soil and plant L. chuanxiong samples were determined by using X-ray fluorescence spectrometry (XRF) and ICP-MS,etc. Spearman correlation test was used to evaluate the correlations of rhizosphere soil and each portion of L. chuanxiong,to screen out “characteristic elements”. Bray-Curtis similarity indexes based on all elements and "characteristic elements" were used for hierarchical cluster analysis of soil samples, to identify the sample range with similar soil element charateristics to the traditional geo-authentic area of L. chuanxiong. Result:K,Mg,Mn and Rb elements were significantly correlated in rhizosphere soil and plant L. chuanxiong. Geographical differentiation of all elements and four characteristic elements showed that there was a highest similarity between geo-authentic area and its neighbor plots S1-S6 (except plot S4) in soil elements distribution, followed by plots S14-S16. The middle section plots S7-S13 in the expansion areas were quite different from the traditional geo-authentic production areas. Conclusion:The soil element characteristics in the study areas were not completely controlled by geographical distance,but demonstrated the "fault" variation in the areas along longitude. This study provides a theoretical basis for the detrrmination of suitable cultivation area for Ligusticum Chuanxiong, and the natural boundary of its geo-authentic area may be extended an additional 60 km southward along longitude beyond the traditional origin. Additionally, K,Mg,Mn and Rb characteristic elements may be the potential markers to evaluate the suitable soil environment for cultivating L. chuanxiong.

20.
Artigo em Chinês | WPRIM | ID: wpr-828201

RESUMO

OBJECTIVE@#Feature extraction of breast tumors is very important in the breast tumor detection (benign and malignant) in ultrasound image. The traditional quantitative description of breast tumors has some shortcomings, such as inaccuracy. A simple and accurate feature extraction method has been studied.@*METHODS@#In this paper, a new method of boundary feature extraction was proposed. Firstly, the shape histogram of ultrasound breast tumors was constructed. Secondly, the relevant boundary feature factors were calculated from a local point of view, including sum of maximum curvature, sum of maximum curvature and peak, sum of maximum curvature and standard deviation. Based on the boundary features, shape features and texture features, the linear support vector machine classifiers for benign and malignant breast tumor recognition was constructed.@*RESULTS@#The accuracy of boundary features in the benign and malignant breast tumors classification was 82.69%. The accuracy of shape features was 73.08%. The accuracy of texture features was 63.46%. The classification accuracy of the three fusion features was 86.54%.@*CONCLUSIONS@#The classification accuracy of boundary features was higher than that of texture features and shape features. The classification method based on multi-features has the highest accuracy and it describes the benign and malignant tumors from different angles. The research results have practical value.


Assuntos
Humanos , Algoritmos , Neoplasias da Mama , Diagnóstico por Imagem , Máquina de Vetores de Suporte , Ultrassonografia
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