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apparent diffusion coefficient-based histogram analysis differentiates histological subtypes of periampullary adenocarcinoma

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World Journal of Gastroenterology 2019年第40期25卷 6116-6128页

作者： Jing-Yu Lu Hao Yu Xian-Lun Zou Zhen Li Xue-Mei Hu Ya-Qi Shen Dao-Yu Hu Department of Radiology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030Hubei ProvinceChina Department of Radiology the First Affiliated Hospital of Soochow UniversitySuzhou 215006Jiangsu ProvinceChina

BACKGROUND For periampullary adenocarcinoma,the histological subtype is a better prognostic predictor than the site of tumor origin.Intestinal-type periampullary adenocarcinoma(IPAC)is reported to have a better prognosis than the pancreatobiliary-type periampullary adenocarcinoma(PPAC).However,the classification of histological subtypes is difficult to determine before surgery.apparent diffusion coefficient(ADC)histogram analysis is a noninvasive,nonenhanced method with high reproducibility that could help differentiate the two subtypes.AIM To investigate whether volumetric ADC histogram analysis is helpful for distinguishing IPAC from PPAC.METHODS Between January 2015 and October 2018,476 consecutive patients who were suspected of having a periampullary tumor and underwent magnetic resonance imaging(MRI)were reviewed in this retrospective study.Only patients who underwent MRI at 3.0 T with different diffusion-weighted images(b-values=800 and 1000 s/mm^2)and who were confirmed with a periampullary adenocarcinoma were further analyzed.Then,the mean,5th,10th,25th,50th,75th,90th,and 95th percentiles of ADC values and ADCmin,ADCmax,kurtosis,skewness,and entropy were obtained from the volumetric histogram analysis.Comparisons were made by an independent Student's t-test or Mann-Whitney U test.Multiple-class receiver operating characteristic curve analysis was performed to determine and compare the diagnostic value of each significant parameter.RESULTS In total,40 patients with histopathologically confirmed IPAC(n=17)or PPAC(n=23)were enrolled.The mean,5th,25th,50th,75th,90th,and 95th percentiles and ADCmax derived from ADC1000 were significantly lower in the PPAC group than in the IPAC group(P<0.05).However,values derived from ADC800 showed no significant difference between the two groups.The 75th percentile of ADC1000 values achieved the highest area under the curve(AUC)for differentiating IPAC from PPAC(AUC=0.781;sensitivity,91%;specificity,59%;cut-off value,1.50×10^-3 mm^2/s).CONCLUSION Volumetric ADC histogram ana

关键词： Periampullary adenocarcinoma apparent diffusion coefficient Histogram analysis Histopathology Differential diagnosis

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Histogram analysis of apparent diffusion coefficient predicts response to radiofrequency ablation in hepatocellular carcinoma

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Chinese Journal of Cancer Research 2019年第2期31卷 366-374页

作者： Xiaohong Ma Han Ouyang Shuang Wang Meng Wang Chunwu Zhou Xinming Zhao Department of Diagnostic Radiology National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital Chinese Academy of Medical Sciences Peking Union Medical College Department of Epidemiology National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital Chinese Academy of Medical Sciences Peking Union Medical College

Objective: The aim of this study was to predict tumor progression in patients with hepatocellular carcinoma(HCC) treated with radiofrequency ablation(RFA) using histogram analysis of apparent diffusion coefficients(ADC).Methods: Breath-hold diffusion weighted imaging(DWI) was performed in 64 patients(33 progressive and 31 stable) with biopsy-proven HCC prior to RFA. All patients had pre-treatment magnetic resonance imaging(MRI)and follow-up computed tomography(CT) or MRI. The ADC values(ADC_(10), ADC_(30_, ADC_(median) and ADC_(max))were obtained from the histogram's 10 th, 30 th, 50 th and 100 th percentiles. The ratios of ADC_(10), ADC_(30_,ADCmedian and ADCmax to the mean non-lesion area-ADC(RADC_(10), RADC_(30_, RADC_(median), and RADC_(max)) were calculated. The two patient groups were compared. Key predictive factors for survival were determined using the univariate and multivariate analysis of the Cox model. The Kaplan-Meier survival analysis was performed, and pairs of survival curves based on the key factors were compared using the log-rank test.Results: The ADC_(30_, ADCmedian, ADCmax, RADC_(30_, RADC_(median), and RADC_(max) were significantly larger in the progressive group than in the stable group(P<0.05). The median progression-free survival(PFS) was 22.9 months for all patients. The mean PFS for the stable and progressive groups were 47.7±1.3 and 9.8±1.3 months,respectively. Univariate analysis indicated that RADC_(10), RADC_(30_, and RADC_(median) were significantly correlated with the PFS [hazard ratio(HR)=31.02, 43.84, and 44.29, respectively, P<0.05 for all]. Multivariate analysis showed that RADCmedian was the only independent predictor of tumor progression(P=0.04). And the cutoff value of RADC_(median) was 0.71.Conclusions: Pre-RFA ADC histogram analysis might serve as a useful biomarker for predicting tumor progression and survival in patients with HCC treated with RFA.

关键词： Diffusion-weighted imaging apparent diffusion coefficient histogram analysis hepatocellular carcinoma radiofrequency ablation survival time

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Nutritional value of a partially defatted and a highly defatted black soldier fly larvae (Hermetia illucens L.) meal for broiler chickens: apparent nutrient digestibility,apparent metabolizable energy and apparent ileal amino acid digestibility

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Journal of Animal Science and Biotechnology 2017年第4期8卷 897-905页

作者： Achille Schiavone Michele De Marco Silvia Martínez Sihem Dabbou Manuela Renna Josefa Madrid Fuensanta Hernandez Luca Rotolo Pierluca Costa Francesco Gai Laura Gasco Department of Veterinary Sciences University of Turin Largo Paolo Braccini 2 10095 Grugliasco TO Italy Department of Animal Production University of Murcia Campus de Espinardo 30071 Murcia Spain Department of Agricultural Forest and Food Sciences University of Turin Largo Paolo Braccini 2 10095 Grugliasco TO Italy Institute of Science of Food Production National Research Council Largo Paolo Braccini 2 10095 Grugliasco TO Italy

Background: The study aimed to determine the apparent total tract digestibility coefficients(ATTDC) of nutrients, the apparent metabolizable energy(AME and AMEn) and the amino acid(AA) apparent ileal digestibility coefficients(AIDC)of a partially defatted(BSFp) and a highly defatted(BSFh) black soldier fly larvae meal. The experimental diets were: a basal diet and two diets prepared by substituting 250 g/kg(w/w) of the basal diet with BSFp or BSFh, respectively.Results: Significant differences were found between BSFp and BSFh meals for ATTDC of the nutrients: BSFp resulted more digestible than BSFh, except for ATTDC of CP which did not differed between meals, while a statistical trend was observed for ATTDC of DM and EE. The AME and AMEn values were significantly(P < 0.05) different between the two BSF meals, with higher levels for BSFp(16.25 and 14.87 MJ/kg DM, respectively). The AIDC of the AA in BSFp ranged from 0.44 to 0.92, while in BSFh they ranged from 0.45 to 0.99. No significant differences were observed for the AA digestibility(0.77 and 0.80 for BSFp and BSFh, respectively), except for glutamic acid, proline and serine that were more digestible in the BSFh meal(P < 0.05).Conclusions: Defatted BSF meals can be considered as an excellent source of AME and digestible AA for broilers with a better efficient nutrient digestion. These considerations suggested the effective utilization of defatted BSF larvae meal in poultry feed formulation.

关键词： Amino acid apparent digestibility Black soldier fly meal Broiler chicken Metabolizable energy

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Characterization and apparent Kinetics of Polymerization of 1-Decene Catalyzed by Boron Trifluoride/Alcohol System

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China Petroleum Processing & Petrochemical Technology 2017年第3期19卷 16-22页

作者： Wang Sihan Wang Libo Liu Tong Ma Lili Huo Hongliang Wang Jian Daqing Petrochemical Research Center of PetroChina Daqing 163714 Northeast Petroleum University Daqing 163318

Poly-α-olefin(PAO) synthetic oil is the base oil of high-quality lubricants, and has a huge market potential.We illustrate PAO synthesis by catalytic polymerization of 1-decene with a boron trifluoride(BF_3)/alcohol system. Gas chromatography–mass spectrometry, proton nuclear magnetic resonance and ^(13) C nuclear magnetic resonance analysis confirmed dimer, trimer and tetramer structures of PAO. Each component contained branched chains with a 1,2 insertion of a head-to-tail link; a 2,1 insertion of a tail-to-tail link and a methyl-containing linked structure. At a low conversion rate, the reaction rate was related directly with the reaction temperature and the catalyst/1-decene concentration. An apparent kinetic equation for PAO formation was determined during 1-decene polymerization.

关键词： poly-α-olefin 1-decene boron trifluoride product structure apparent kinetics

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Influence of Perpendicular Magnetic Field on apparent Density and Microstructure of Magnetic Fluid

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Chinese Physics Letters 2012年第10期29卷 204-208页

作者：李艳琴李学慧 School of Physics and Optoelectronic Technology Dalian University of TechnologyDalian 116024 College of Physical Science and Technology Dalian UniversityDalian 116622

The formula for a magnetic fluid's apparent density is derived based on Bernoulli's equation of magnetic fluid,and the distribution of the magnetic fluid's apparent density is measured by the intelligent apparatus of measuring a magnetic fluid's apparent density in an applied perpendicular magnetic field.Magnetic particle chain-like alignments are observed by a transmission electron microscope(TEM).Without an applied magnetic field,the magnetic fluid's density is equal everywhere and the distribution of magnetic particles is homogeneous and unordered.When magnetic induction and magnetic induction gradient gather strength in an applied perpendicular magnetic field,the magnetic fluid's apparent density increases gradually,and more chain-like structures are formed and aligned with the direction of the magnetic field.The results of magnetic particle alignments are correspondent with the distribution of the magnetic fluid's apparent density.Both of them result from particle-particle interactions and particle-carrier liquid interactions,which are eventually controlled by the applied magnetic induction and magnetic induction gradient distribution.

关键词： Microstructure apparent Magnetic

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Analysis of gas transport behavior in organic and inorganic nanopores based on a unified apparent gas permeability model

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Petroleum Science 2020年第1期17卷 168-181页

作者： Qi Zhang Wen-Dong Wang Yilihamu Kade Bo-Tao Wang Lei Xiong Key Laboratory of Tectonics and Petroleum Resources China University of GeosciencesWuhan 430074HubeiChina School of Petroleum Engineering China University of Petroleum(East China)Qingdao 266580ShandongChina Institute of Ground Engineering Engineering Technology Research Institute of PetroChina Xinjiang Oilfield CompanyKaramay 834000XinjiangChina Oil Production Plant 5 of PetroChina Changqing Oilfield Company Changqing OilfieldXi’an 710200ShaanxiChina Oil Production Plant 1 of PetroChina Xinjiang Oilfield Company Karamay 834000XinjiangChina

Different from the conventional gas reservoirs,gas transport in nanoporous shales is complicated due to multiple transport mechanisms and reservoir characteristics.In this work,we presented a unified apparent gas permeability model for real gas transport in organic and inorganic nanopores,considering real gas effect,organic matter(OM)porosity,Knudsen diffusion,surface diffusion,and stress dependence.Meanwhile,the effects of monolayer and multilayer adsorption on gas transport are included.Then,we validated the model by experimental results.The influences of pore radius,pore pressure,OM porosity,temperature,and stress dependence on gas transport behavior and their contributions to the total apparent gas permeability(AGP)were analyzed.The results show that the adsorption effect causes Kn(OM)>Kn(IM)when the pore pressure is larger than 1 MPa and the pore radius is less than 100 nm.The ratio of the AGP over the intrinsic permeability decreases with an increase in pore radius or pore pressure.For nanopores with a radius of less than 10 nm,the effects of the OM porosity,surface diffusion coefficient,and temperature on gas transport cannot be negligible.Moreover,the surface diffusion almost dominates in nanopores with a radius less than 2 nm under high OM porosity conditions.For the small-radius and low-pressure conditions,gas transport is governed by the Knudsen diffusion in nanopores.This study focuses on revealing gas transport behavior in nanoporous shales.

关键词： Gas transport apparent gas permeability model Gas adsorption Surface diffusion Stress dependence

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Prediction of different stages of rectal cancer: Texture analysis based on diffusion-weighted images and apparent diffusion coefficient maps

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World Journal of Gastroenterology 2020年第17期26卷 2082-2096页

作者： Jian-Dong Yin Li-Rong Song He-Cheng Lu Xu Zheng Department of Radiology Shengjing Hospital of China Medical UniversityShenyang 110003Liaoning ProvinceChina College of Medicine and Biological Information Engineering Northeastern UniversityShenyang 110036Liaoning ProvinceChina Department of Clinical Oncology Shengjing Hospital of China Medical UniversityShenyang 110011Liaoning ProvinceChina

BACKGROUND It is evident that an accurate evaluation of T and N stage rectal cancer is essential for treatment planning.It has not been extensively investigated whether texture features derived from diffusion-weighted imaging(DWI)images and apparent diffusion coefficient(ADC)maps are associated with the extent of local invasion(pathological stage T1-2 vs T3-4)and nodal involvement(pathological stage N0 vs N1-2)in rectal cancer.AIM To predict different stages of rectal cancer using texture analysis based on DWI images and ADC maps.METHODS One hundred and fifteen patients with pathologically proven rectal cancer,who underwent preoperative magnetic resonance imaging,including DWI,were enrolled,retrospectively.The ADC measurements(ADCmean,ADCmin,ADCmax)as well as texture features,including the gray level co-occurrence matrix parameters,the gray level run-length matrix parameters and wavelet parameters were calculated based on DWI(b=0 and b=1000)images and the ADC maps.Independent sample t-tests or Mann-Whitney U tests were used for statistical analysis.Multivariate logistic regression analysis was conducted to establish the models.The predictive performance was validated by receiver operating characteristic curve analysis.RESULTS Dissimilarity,sum average,information correlation and run-length nonuniformity from DWIb=0 images,gray level nonuniformity,run percentage and run-length nonuniformity from DWIb=1000 images,and dissimilarity and run percentage from ADC maps were found to be independent predictors of local invasion(stage T3-4).The area under the operating characteristic curve of the model reached 0.793 with a sensitivity of 78.57%and a specificity of 74.19%.Sum average,gray level nonuniformity and the horizontal components of symlet transform(SymletH)from DWIb=0 images,sum average,information correlation,long run low gray level emphasis and SymletH from DWIb=1000 images,and ADCmax,ADCmean and information correlation from ADC maps were identified as independent predictors of nodal involvement.The area under the

关键词： Rectal cancer Diffusion weighted imaging apparent diffusion coefficient Texture analysis

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Diffusion-weighted magnetic resonance imaging in cancer: Reported apparent diffusion coefficients,in-vitro and invivo reproducibility

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World Journal of Radiology 2016年第1期8卷 21-49页

作者： Maysam M Jafar Arman Parsai Marc E Miquel Barts Cancer Institute Queen Mary University of London Clinical Physics Barts Health NHS Trust Radiology Barts Health NHS Trust William Harvey Research Institute Queen Mary University of London

There is considerable disparity in the published apparent diffusion coefficient(ADC) values across different anatomies. Institutions are increasingly assessing repeatability and reproducibility of the derived ADC to determine its variation,which could potentially be used as an indicator in determining tumour aggressiveness or assessing tumour response. In this manuscript,a review of selected articles published to date in healthy extracranial body diffusion-weighted magnetic resonance imaging is presented,detailing reported ADC values and discussing their variation across different studies. In total 115 studies were selected including 28 for liver parenchyma,15 for kidney(renal parenchyma),14 for spleen,13 for pancreatic body,6 for gallbladder,13 for prostate,13 for uterus(endometrium,myometrium,cervix) and 13 for fibroglandular breast tissue. Median ADC values in selected studies were found to be 1.28 × 10-3 mm2/s in liver,1.94 × 10-3 mm2/s in kidney,1.60 × 10-3 mm2/s in pancreatic body,0.85 × 10-3 mm2/s in spleen,2.73 × 10-3 mm2/s in gallbladder,1.64 × 10-3 mm2/s and 1.31 × 10-3 mm2/s in prostate peripheral zone and central gland respectively(combined median value of 1.54×10-3 mm2/s),1.44 × 10-3 mm2/s in endometrium,1.53 × 10-3 mm2/s in myometrium,1.71 × 10-3 mm2/s in cervix and 1.92 × 10-3 mm2/s in breast. In addition,six phantom studies and thirteen in vivo studies were summarized to compare repeatability and reproducibility of the measured ADC. All selected phantom studies demonstrated lower intra-scanner and inter-scanner variation compared to in vivo studies. Based on the findings of this manuscript,it is recommended that protocols need to be optimised for the body part studied and that system-induced variability must be established using a standardized phantom in any clinical study. Reproducibility of the measured ADC must also be assessed in a volunteer population,as variations are far more significant in vivo compared with phantom studies.

关键词： Diffusion-weighted magnetic resonance imaging apparent diffusion coefficient reproducibility apparent diffusion coefficient Cancer imaging Extracranial organs

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The Value of apparent Diffusion Coefficient in Differential Diagnosis of Ovarian Cystic Adenoid Tumors

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Proceedings of Anticancer Research 2019年第2期3卷 1-6页

作者： Lin Sun Ruirui Xu Wei Yan Meng Zhao Fei Chen Department of Radiology Binzhou People’s HospitalBinzhouShandong256600China Department of Nephrology Binzhou People’s HospitalBinzhouShandong256600China Department of Pathology Binzhou People’s HospitalBinzhouShandong256600China

Objective:To quantitatively analyze apparent diffusion coefficient(ADC)value of cystic composition and solid composition in ovarian cystadenocarcinoma,borderline cystadenoma and cystadenoma by 3.0T magnetic resonance imaging(MRI),and to investigate its diagnostic and differential diagnostic values in ovarian cystic adenoid tumors.Methods:Retrospective analysis was carried out on 28 patients with ovarian cystic adenoid tumor as confirmed by surgical and pathological examinations.Examination was performed by Siemens 3.0T MRI scanner.Tumor size,margin,composition(cystic or solid),signal characteristic and presence of ascites were observed.Combined with localization using T2WI and diffusion weighted imaging(DWI),ADC value was calculated from ADC mapping using region of interest ROI(the largest surface area of cystic and solid compositions in tumor).Statistical analysis was performed.Results:Among the 28 ovarian tumors,there were 13 cases of cystadenomas(5 serous cystadenomas and 9 mucinous cystadenomas),4 borderline mucinous cystadenomas and 11 cystadenocarcinoma(9 serous cystadenocarcinoma and 2 mucinous cystadenocarcinoma).There was no significant intragroup difference in ADC values of cystic composition and solid composition in ovarian cystadenoma and cystadenocarcinoma respectively(P>0.05).The ADC value of solid composition between benign cystadenoma and borderline cystadenoma(P0.05).Conclusion:Quantitative analysis of ADC value of solid composition using 3.0T MRI has great value in differential diagnosis of benign and malignant ovarian cystic adenoid tumors.Its combination with conventional MRI method can improve the accuracy of diagnosis of ovarian cystic adenoid tumors.

关键词： apparent diffusion coefficient Magnetic resonance imaging Ovarian cystadenoma Cystadenocarcinoma Borderline cystadenoma

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Magnetic resonance imaging apparent diffusion coefficient before and after neoadjuvant chemotherapy in patients with breast cancer and its correlation with tumor load

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Journal of Hainan Medical University 2018年第9期24卷 52-56页

作者： Si-Qi Wang Ping Jiang Radiology Department Zigong Fourth People's Hospital in Sichuan ProvinceZigongSichuan Province643000

Objective:To study the magnetic resonance imaging apparent diffusion coefficient (ADC) before and after neoadjuvant chemotherapy in patients with breast cancer and its correlation with tumor load.Methods: Patients with stage II-III breast cancer who intended to receive radical operation for breast cancer in our hospital between May 2015 and February 2018 were selected and divided into the experimental group who accepted neoadjuvant chemotherapy and the control group who received surgery directly according to the adoption of preoperative neoadjuvant chemotherapy or not in the history data. Experimental group underwent magnetic resonance imaging before and after neoadjuvant chemotherapy to measure the ADC, and control group underwent magnetic resonance imaging before surgery to measure the ADC;the tumor tissues surgically removed from the two groups of patients were collected to measure the expression of oncogenes and invasion genes.Results:ADC value of experimental group after neoadjuvant chemotherapy was higher than that before neoadjuvant chemotherapy, ADC value of experimental group before neoadjuvant chemotherapy was not significantly different from that of control group whereas ADC value after neoadjuvant chemotherapy was significantly higher than that of control group;MCM3, CyclinD1, TC-1,β-catenin, YAP and MMP2 mRNA expression levels in surgically removed tumor tissues of experimental group were significantly lower than those of control group whereas CCN5, ARID1A and PDCD4 mRNA expression levels were significantly higher than those of control group;MCM3, CyclinD1, TC-1,β-catenin, YAP and MMP2 mRNA expression levels in tumor tissues with high ADC value were significantly lower than those in tumor tissues with low ADC value whereas CCN5, ARID1A and PDCD4 mRNA expression levels were significantly higher than those in tumor tissues with low ADC value.Conclusion:The increase of ADC after breast cancer neoadjuvant chemotherapy is related to the activity of cancer cell proliferation and invasion, and can be used t

关键词： Breast cancer Neoadjuvant chemotherapy apparent diffusion coefficient Oncogene Invasion gene

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