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The diagnostic value of high-frequency ultrasonography in biliary atresia 被引量:13
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作者 Li-Ping Jiang Yun-Chao Chen +5 位作者 Lu Ding Xiao-Ling Liu Kai-Yan Li Dao-Zhong Huang Ai-Yun Zhou Qing-Ping Zhang 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2013年第4期415-422,共8页
BACKGROUND: It is a globally challenging problem to differentially diagnose biliary atresia (BA) from other disease processes causing infantile cholestatic jaundice. The high frequency ultrasonography (HUS) yields muc... BACKGROUND: It is a globally challenging problem to differentially diagnose biliary atresia (BA) from other disease processes causing infantile cholestatic jaundice. The high frequency ultrasonography (HUS) yields much improved spatial resolution and therefore, might show better image in BA diagnostic examination. The present study was to evaluate the HUS on the diagnosis of BA in infants with jaundice. METHODS: Fifty-one infants with neonatal jaundice were scanned with ultrasonography. Images included gallbladder, bile duct, right hepatic artery (RHA), portal vein (PV) and triangular cord (TC) sign, magnetic resonance imaging and additionally laboratory tests and histopathology reports were assessed. RESULTS: Twenty-three BA and 28 non-BA cases were con firmed. The sensitivity, specificity, and accuracy of HUS were 91.3%, 92.9%, and 92.2%, respectively. All of these indices were significantly higher than those of conventional ultrasonography (P【0.01) and MR cholangiopancreatography (P【0.05). The HUS features, included a positive TC sign, an increased RHA diameter and RHA-diameter to portal-vein-diameter ratio (RHA/PV) and abnormal gallbladder, were important in the diagnosis of BA. CONCLUSION: HUS provided better imaging of BA and should be considered as a primary modality in the differential diagnosis of infantile jaundice. 展开更多
关键词 neonatal jaundice biliary atresia high-frequency ultrasonography
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Early Detection of Lesions of Dorsal Artery of Foot in Patients with Type 2 Diabetes Mellitus by High-frequency Ultrasonography 被引量:150
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作者 张艳容 李雯静 +3 位作者 严天慰 鲁成发 周翔 黄艳 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2009年第3期387-390,共4页
This study evaluated the value of high-frequency ultrasonograpy for early detection of dorsal artery of foot in patients with type 2 diabetes mellitus (MD). Eighty subjects including 40 patients with type 2 MD (T2D... This study evaluated the value of high-frequency ultrasonograpy for early detection of dorsal artery of foot in patients with type 2 diabetes mellitus (MD). Eighty subjects including 40 patients with type 2 MD (T2DM group) and 40 healthy volunteers (NC group) were recruited. The intima-media thickness (IMT), the inner diameter and the perfusion of dorsal artery of foot were measured by using high-frequency ultrasonograpy. Meanwhile, the parameters of vascular elasticity, including stiffness parameter (]3), pressure-strain elastic modulus (Ep), arterial compliance (AC), augment index (AI), and pulse wave conducting velocity (PWV]3) were detected by means of echo-tracking technique. The results showed that no significant difference was found in the IMT, systolic diameter (Ds), diastolic diameter (Dd) and peak systolic velocity (PSV) between T2DM and NC groups. Ep and PWVβ were increased, and AC was decreased in T2DM group as compared with those in NC group with the differences being significant (P〈0.05 for all). There was no significant difference in β and AI between T2DM and NC groups. It was concluded that high-frequency ultra- sonography in combination with echo-tracking technique is sensitive and non-invasive, and can be used for early detection of sclerosis of the lower extremity artery in patients with type 2 MD. 展开更多
关键词 high frequency ultrasonography dorsal artery of foot ELASTICITY type 2 diabetes mellitus
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Kinematic deformation and intensity assessment of the 2021 Maduo M_(S)7.4 earthquake in Qinghai revealed by high-frequency GNSS
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作者 Yu Li Yuebing Wang +2 位作者 Lijiang Zhao Hongbo Shi Pingping Wang 《Geodesy and Geodynamics》 EI CSCD 2024年第3期230-240,共11页
Rapid acquisition of the kinematic deformation field and seismic intensity distribution of large earthquakes is crucial for postseismic emergency rescue,disaster assessment,and future seismic risk research.The advance... Rapid acquisition of the kinematic deformation field and seismic intensity distribution of large earthquakes is crucial for postseismic emergency rescue,disaster assessment,and future seismic risk research.The advancement of GNSS observation and data processing makes it play an important role in this field,especially the high-frequency GNSS.We used the differential positioning method to calculate the 1 HZ GNSS data from 98 sites within 1000 km of the M_(S)7.4 Maduo earthquake epicenter.The kinematic deformation field and the distribution of the seismic intensity by using the peak ground velocity derived from displacement waveforms were obtained.The results show that:1)Horizontal coseismic response deformation levels ranging from 25 mm to 301 mm can be observed within a 1000 km radius from the epicenter.Coseismic response deformation on the east and west sides shows bilateral asymmetry,which markedly differs from the symmetry presented by surface rupture.2)The seismic intensity obtained through high-frequency GNSS and field investigations exhibits good consistency of the scope and orientation in the high seismic intensity area,although the former is generally slightly smaller than the latter.3)There may exist obstacles on the eastern side of the seismogenic fault.The Maduo earthquake induced a certain tectonic stress loading effect on the western Kunlun Pass-Jiangcuo fault(KPJF)and Maqin-Maqu segment,resulting in higher seismic risk in the future. 展开更多
关键词 Maduo earthquake high-frequency GNSS Kinematic deformation Seismic intensity
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Dynamic Response of Foundations during Startup of High-Frequency Tunnel Equipment
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作者 Dawei Ruan Mingwei Hu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期821-844,共24页
The specialized equipment utilized in long-line tunnel engineering is evolving towards large-scale,multifunctional,and complex orientations.The vibration caused by the high-frequency units during regular operation is ... The specialized equipment utilized in long-line tunnel engineering is evolving towards large-scale,multifunctional,and complex orientations.The vibration caused by the high-frequency units during regular operation is supported by the foundation of the units,and the magnitude of vibration and the operating frequency fluctuate in different engineering contexts,leading to variations in the dynamic response of the foundation.The high-frequency units yield significantly diverse outcomes under different startup conditions and times,resulting in failure to meet operational requirements,influencing the normal function of the tunnel,and causing harm to the foundation structure,personnel,and property in severe cases.This article formulates a finite element numerical computation model for solid elements using three-dimensional elastic body theory and integrates field measurements to substantiate and ascertain the crucial parameter configurations of the finite element model.By proposing a comprehensive startup timing function for high-frequency dynamic machines under different startup conditions,simulating the frequency andmagnitude variations during the startup process,and suggesting functions for changes in frequency and magnitude,a simulated startup schedule function for high-frequency machines is created through coupling.Taking into account the selection of the transient dynamic analysis step length,the dynamic response results for the lower dynamic foundation during its fundamental frequency crossing process are obtained.The validation checks if the structural magnitude surpasses the safety threshold during the critical phase of unit startup traversing the structural resonance region.The design recommendations for high-frequency units’dynamic foundations are provided,taking into account the startup process of the machine and ensuring the safe operation of the tunnel. 展开更多
关键词 Tunnel equipment high-frequency units startup conditions transient dynamics dynamic response foundation design
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Effects of unilateral superimposed high-frequency jet ventilation on porcine hemodynamics and gas exchange during one-lung flooding
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作者 Thomas Lesser Frank Wolfram +1 位作者 Conny Braun Reiner Gottschall 《World Journal of Experimental Medicine》 2024年第1期88-99,共12页
BACKGROUND Superimposed high-frequency jet ventilation(SHFJV)is suitable for respiratory motion reduction and essential for effective lung tumor ablation.Fluid filling of the target lung wing one-lung flooding(OLF)is ... BACKGROUND Superimposed high-frequency jet ventilation(SHFJV)is suitable for respiratory motion reduction and essential for effective lung tumor ablation.Fluid filling of the target lung wing one-lung flooding(OLF)is necessary for therapeutic ultrasound applications.However,whether unilateral SHFJV allows adequate hemodynamics and gas exchange is unclear.AIM To compared SHFJV with pressure-controlled ventilation(PCV)during OLF by assessing hemodynamics and gas exchange in different animal positions.METHODS SHFJV or PCV was used alternatingly to ventilate the non-flooded lungs of the 12 anesthetized pigs during OLF.The animal positions were changed from left lateral position to supine position(SP)to right lateral position(RLP)every 30 min.In each position,ventilation was maintained for 15 min in both modalities.Hemodynamic variables and arterial blood gas levels were repeatedly measured.RESULTS Unilateral SHFJV led to lower carbon dioxide removal than PCV without abnormally elevated carbon dioxide levels.SHFJV slightly decreased oxygenation in SP and RLP compared with PCV;the lowest values of PaO_(2) and PaO_(2)/FiO_(2) ratio were found in SP[13.0;interquartile range(IQR):12.6-5.6 and 32.5(IQR:31.5-38.9)kPa].Conversely,during SHFJV,the shunt fraction was higher in all animal positions(highest in the RLP:0.30).CONCLUSION In porcine model,unilateral SHFJV may provide adequate ventilation in different animal positions during OLF.Lower oxygenation and CO_(2) removal rates compared to PCV did not lead to hypoxia or hypercapnia.SHFJV can be safely used for lung tumor ablation to minimize ventilation-induced lung motion. 展开更多
关键词 One-lung ventilation Unilateral superimposed high-frequency jet ventilation One-lung flooding
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Therapeutic efficacy of methylprednisolone sodium succinate via diverse administration routes for mid-to high-frequency sudden sensorineural hearing loss
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作者 Xiang-Da Meng Ting-Ting Li Li-Min Deng 《World Journal of Clinical Cases》 SCIE 2024年第18期3321-3331,共11页
BACKGROUND Sudden sensorineural hearing loss(SSNHL),characterized by a rapid and unexplained loss of hearing,particularly at moderate to high frequencies,presents a significant clinical challenge.The therapeutic use o... BACKGROUND Sudden sensorineural hearing loss(SSNHL),characterized by a rapid and unexplained loss of hearing,particularly at moderate to high frequencies,presents a significant clinical challenge.The therapeutic use of methylprednisolone sodium succinate(MPSS)via different administration routes,in combination with conventional medications,remains a topic of interest.AIM To compare the therapeutic efficacy of MPSS administered via different routes in combination with conventional drugs for the treatment of mid-to high-frequency SSNHL.METHODS The medical records of 109 patients with mid-to high-frequency SSNHL were analyzed.The patients were divided into three groups based on the route of administration:Group A[intratympanic(IT)injection of MPSS combined with mecobalamin and Ginkgo biloba leaf extract injection],Group B(intravenous injection of MPSS combined with mecobalamin and Ginkgo biloba leaf extract injection),and Group C(single IT injection of MPSS).The intervention effects were compared and analyzed.RESULTS The posttreatment auditory thresholds in Group A(21.23±3.34)were significantly lower than those in Groups B(28.52±3.36)and C(30.23±4.21;P<0.05).Group A also exhibited a significantly greater speech recognition rate(92.23±5.34)than Groups B and C.The disappearance time of tinnitus,time to hearing recovery,and disappearance time of vertigo in Group A were significantly shorter than those in Groups B and C(P<0.05).The total effective rate in Group A(97.56%)was significantly greater than that in Groups B and C(77.14%and 78.79%,χ^(2)=7.898,P=0.019).Moreover,the incidence of adverse reactions in Groups A and C was significantly lower than that in Group B(4.88%,3.03%vs 2.57%,χ^(2)=11.443,P=0.003),and the recurrence rate in Group A was significantly lower than that in Groups B and C(2.44%vs 20.00%vs 21.21%,χ^(2)=7.120,P=0.028).CONCLUSION IT injection of MPSS combined with conventional treatment demonstrates superior efficacy and safety compared to systemic administration via intravenous infusion and a single IT injection of MPSS.This approach effectively improves patients'hearing and reduces the risk of disease recurrence. 展开更多
关键词 Sudden loss of hearing at middle-and high-frequency of the descending type Methylprednisolone sodium succinate Intratympanic injection Intravenous injection
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Radio-frequency measurements of energetic-electron-driven emissions using high-frequency magnetic probe on XuanLong-50 spherical torus
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作者 王明远 伦秀春 +3 位作者 薄晓坤 刘兵 刘阿娣 石跃江 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第4期33-38,共6页
A high-frequency magnetic probe is designed and developed on the XuanL ong-50(EXL-50)spherical torus to measure high-frequency magnetic field fluctuation.The magnetic loop,radio filters,radio-frequency limiter,and dat... A high-frequency magnetic probe is designed and developed on the XuanL ong-50(EXL-50)spherical torus to measure high-frequency magnetic field fluctuation.The magnetic loop,radio filters,radio-frequency limiter,and data acquisition system of the probe are comprehensively examined.The fluctuation data from the EXL-50 plasma are analyzed in the time–frequency domain using fast Fourier transforms.Moreover,distinct high-frequency instabilities are detected using this diagnostic system.In particular,significant frequency chirping is observed,which is consistent with the bumpon-tail drive instability predicted using the Berk–Breizman model. 展开更多
关键词 high-frequency magnetic probe high-frequency instabilities XuanLong-50
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Tuning magneto-dielectric properties of Co_(2)Z ferrites via Gd doping for high-frequency applications
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作者 武剑 卢冰 +6 位作者 张颖 陈一鑫 孙凯 陈大明 李强 刘颖力 李颉 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第9期468-473,共6页
Magneto-dielectric properties of Co_(2)Z ferrite materials are tuned via Gd doping for applications in high-frequency antennas and filters in the present work.Ba_(3)Co_(2)Fe_(24-x)Gd_(x)O_(41)(x=0.00,0.05,0.10,0.15,an... Magneto-dielectric properties of Co_(2)Z ferrite materials are tuned via Gd doping for applications in high-frequency antennas and filters in the present work.Ba_(3)Co_(2)Fe_(24-x)Gd_(x)O_(41)(x=0.00,0.05,0.10,0.15,and 0.20)materials are successfully prepared by using solid-state method at 925℃for 4 h with 2.5-wt%Bi_(2)O_(3)sintering aids.The content of Gd^(3+)ion can affect micromorphology,grain size,bulk density,and magneto-dielectric properties of the ferrite.With Gd^(3+)ion content increasing,saturation magnetization(Ms)first increases and then decreases.The maximum value of Ms is 44.86 emu/g at x=0.15.Additionally,sites occupied by Gd^(3+)ions can change magnetic anisotropy constant of the ferrite.Magnetocrystalline anisotropy constant(K_1)is derived from initial magnetization curve,and found to be related to spin-orbit coupling and intersublattice interactions between metal ions.The real part of magnetic permeability(μ′)and real part of dielectric permittivity(ε′)are measured in a frequency range of 10 MHz-1 GHz.When x=0.15,material has excellent magneto-dielectric properties(μ′≈12.2 andε′≈17.61),low magnetic loss(tanδμ≈0.03 at 500 MHz),and dielectric loss(tanδε≈0.04 at 500 MHz).The results show that Gd-doped Co_(2)Z ferrite has broad application prospects in multilayer filters and high-frequency antennas. 展开更多
关键词 Co_(2)Z ferrite magneto-dielectric properties Gd doping high-frequency applications
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Beta-HCG Levels and Ovarian Ultrasonography Results among Non-Pregnant Women of Reproductive Age in Port Harcourt, Nigeria: A Cross-Sectional Study
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作者 Celine C. Agonsi Francis Anacletus +2 位作者 Joel Aluko Chinemerem Eleke Joy C. Samuel 《Journal of Biosciences and Medicines》 2024年第5期233-241,共9页
Background: Certain ovarian cancers that were previously common in postmenopausal women are now increasingly observed in women of reproductive age. The research on using β-HCG as a diagnostic biomarker for ovarian ca... Background: Certain ovarian cancers that were previously common in postmenopausal women are now increasingly observed in women of reproductive age. The research on using β-HCG as a diagnostic biomarker for ovarian cancer in women of reproductive age is ongoing. Aim: This study assessed the level of serum β-HCG in non-pregnant women of reproductive age and determined its potential association with suspicious ovarian ultrasonography results. Methods: The study was conducted in Port Harcourt, Nigeria. This study adopted a cross-sectional design on a quota sample of 224 case notes of women aged 18 - 40 years obtained from eight diagnostic centres. A data extraction form was used for data collection. Data analysis employed descriptive statistics, Chi-square, Fisher’s exact test, and Odds Ratio at 95% confidence and 5% significance levels. Results: About 5.8% of the participants exhibited detectable levels of serum β-HCG above 5 IU/L (World Health Organization reference) at a mean concentration of 5.87 (±1.75) IU/L. About 4.0% of the participants had suspicious ovarian lesions identified through ultrasonography. Participants with elevated serum β-HCG levels above the WHO reference were 59 times more likely to have suspicious ovarian lesions (Odds ratio: 59.4, 95%CI: 12.3 - 287.8, p β-HCG level and age (p = 0.041) as well as parity (p Conclusion: Serum β-HCG levels above the WHO reference in non-pregnant women were associated with suspicious ovarian lesions. More rigorous primary research, systematic reviews, and meta-analyses are needed to confirm the findings of this study. 展开更多
关键词 Biomarkers Ovarian Cancer PREGNANCY ultrasonography
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Endoscopic ultrasonography-related diagnostic accuracy and clinical significance on small rectal neuroendocrine neoplasms
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作者 Jun Weng Yu-Fan Chen +5 位作者 Shu-Han Li Yan-Hua Lv Ruo-Bing Chen Guo-Liang Xu Shi-Yong Lin Kun-Hao Bai 《World Journal of Gastroenterology》 SCIE CAS 2024年第7期774-778,共5页
This research aimed to examine the diagnostic accuracy and clinical significance of endoscopic ultrasonography(EUS)in the context of small rectal neuroendocrine neoplasms(NENs).A total of 108 patients with rectal sube... This research aimed to examine the diagnostic accuracy and clinical significance of endoscopic ultrasonography(EUS)in the context of small rectal neuroendocrine neoplasms(NENs).A total of 108 patients with rectal subepithelial lesions(SELs)with a diameter of<20 mm were included in the analysis.The diagnosis and depth assessment of EUS was compared to the histology findings.The prevalence of NENs in rectal SELs was 78.7%(85/108).The sensitivity of EUS in detecting rectal NENs was 98.9%(84/85),while the specificity was 52.2%(12/23).Overall,the diagnostic accuracy of EUS in identifying rectal NENs was 88.9%(96/108).The overall accuracy rate for EUS in assessing the depth of invasion in rectal NENs was 92.9%(78/84).Therefore,EUS demonstrates reasonable diagnostic accuracy in detecting small rectal NENs,with good sensitivity but inferior specificity.EUS may also assist physicians in assessing the depth of invasion in small rectal NENs before endoscopic excision. 展开更多
关键词 Rectal neuroendocrine neoplasms Endoscopic ultrasonography DIAGNOSIS Depth of invasion
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Perioperative and long-term results of ultrasonography-guided single-and multiple-tract percutaneous nephrolithotomy for staghorn calculi
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作者 Rui-Xiang Cheng Ni Dai +2 位作者 Yan-Min Wang Pei Qi Fen Chen 《World Journal of Clinical Cases》 SCIE 2024年第7期1243-1250,共8页
BACKGROUND It is possible that this condition will lead to urosepsis and progressive deterioration of renal function in the absence of surgical intervention.Several recent clinical studies have shown that multi-tract ... BACKGROUND It is possible that this condition will lead to urosepsis and progressive deterioration of renal function in the absence of surgical intervention.Several recent clinical studies have shown that multi-tract percutaneous nephrolithotomy(MPCNL)has a similar stone free rate(SFR)as standard percutaneous nephrolithotomy(S-PCNL).As a result,M-PCNL was also recommended as a treatment option for staghorn calculi.AIM To examine the perioperative and long-term results of ultrasonography-guided single-and M-PCNL.METHODS This was a retrospective cohort study.Between March 2021 and January 2022,the urology department of our hospital selected patients for the treatment of staghorn calculi using percutaneous nephrolithotomy.The primary outcomes were com plication rate and SFR,and the characteristics of patients,operative parameters,laboratory measurements were also collected.RESULTS In total,345 patients were enrolled in the study(186 in the S-PCNL group and 159 in the M-PCNL group).The SFR in the M-PCNL group was significantly higher than that in the S-PCNL group(P=0.033).Moreover,the incidence rates of hydrothorax(P=0.03)and postoperative infection(P=0.012)were higher in the M-PCNL group than in the S-PCNL group.Logistic regression analysis demonstrated that post-operative white blood cell count(OR=2.57,95%CI:1.90-3.47,P<0.001)and stone size(OR=1.59,95%CI:1.27-2.00,P<0.001)were associated with a higher overall complication rate in the S-PCNL group.Body mass index(OR=1.22,95%CI:1.06-1.40,P=0.004)and stone size(OR=1.70,95%CI:1.35-2.15,P<0.001)were associated with increased overall complications in the M-PCNL group.CONCLUSION Multiple access tracts can facilitate higher SFR while slightly increasing the incidence of acceptable complications. 展开更多
关键词 Single-tract percutaneous nephrolithotomy Multiple-tract percutaneous nephrolithotomy Staghorn calculi ultrasonography
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Double contrast-enhanced ultrasonography improves diagnostic accuracy of T staging compared with multi-detector computed tomography in gastric cancer patients
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作者 Yan-Fen Xu Hui-Yun Ma +4 位作者 Gui-Ling Huang Yu-Ting Zhang Xue-Yan Wang Ming-Jie Wei Xiao-Qing Pei 《World Journal of Gastroenterology》 SCIE CAS 2024年第23期3005-3015,共11页
BACKGROUND Gastric cancer(GC)is the most common malignant tumor and ranks third for cancer-related deaths among the worldwide.The disease poses a serious public health problem in China,ranking fifth for incidence and ... BACKGROUND Gastric cancer(GC)is the most common malignant tumor and ranks third for cancer-related deaths among the worldwide.The disease poses a serious public health problem in China,ranking fifth for incidence and third for mortality.Knowledge of the invasive depth of the tumor is vital to treatment decisions.AIM To evaluate the diagnostic performance of double contrast-enhanced ultrasonography(DCEUS)for preoperative T staging in patients with GC by comparing with multi-detector computed tomography(MDCT).METHODS This single prospective study enrolled patients with GC confirmed by preoperative gastroscopy from July 2021 to March 2023.Patients underwent DCEUS,including ultrasonography(US)and intravenous contrast-enhanced ultrasonography(CEUS),and MDCT examinations for the assessment of preoperative T staging.Features of GC were identified on DCEUS and criteria developed to evaluate T staging according to the 8th edition of AJCC cancer staging manual.The diagnostic performance of DCEUS was evaluated by comparing it with that of MDCT and surgical-pathological findings were considered as the gold standard.RESULTS A total of 229 patients with GC(80 T1,33 T2,59 T3 and 57 T4)were included.Overall accuracies were 86.9%for DCEUS and 61.1%for MDCT(P<0.001).DCEUS was superior to MDCT for T1(92.5%vs 70.0%,P<0.001),T2(72.7%vs 51.5%,P=0.041),T3(86.4%vs 45.8%,P<0.001)and T4(87.7%vs 70.2%,P=0.022)staging of GC.CONCLUSION DCEUS improved the diagnostic accuracy of preoperative T staging in patients with GC compared with MDCT,and constitutes a promising imaging modality for preoperative evaluation of GC to aid individualized treatment decision-making. 展开更多
关键词 Double contrast-enhanced ultrasonography Multi-detector computed tomography Gastric cancer T staging
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A study on characteristic indexesof railway ballast bed underhigh-frequency radar
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作者 Shilei Wang Zhan Peng +2 位作者 Guixian Liu Weile Qiang Chi Zhang 《Railway Sciences》 2023年第1期33-47,共15页
Purpose–In this paper,a high-frequency radar test system was used to collect the data of clean ballast bed and fouled ballast bed of ballasted tracks,respectively,for a quantitative evaluation of the condition of rai... Purpose–In this paper,a high-frequency radar test system was used to collect the data of clean ballast bed and fouled ballast bed of ballasted tracks,respectively,for a quantitative evaluation of the condition of railway ballast bed.Design/methodology/approach–Based on original radar signals,the time–frequency characteristics of radar signals were analyzed,five ballast bed condition characteristic indexes were proposed,including the frequency domain integral area,scanning area,number of intersections with the time axis,number of timedomain inflection points and amplitude envelope obtained by Hilbert transform,and the effectiveness and sensitivity of the indexes were analyzed.Findings–The thickness of ballast bed tested at the sleep bottom by high-frequency radar is up to 55 cm,which meets the requirements of ballast bed detection.Compared with clean ballast bed,the values of the five indexes of fouled ballast bed are larger,and the five indexes could effectively show the condition of the ballast bed.The computational efficiency of amplitude envelope obtained by Hilbert transform is 140 s$km1,and the computational efficiency of other indexes is 5 s$km1.The amplitude envelopes obtained by Hilbert transform in the subgrade sections and tunnel sections are the most sensitive,followed by scanning area.The number of intersections with the time axis in the bridge sections was the most sensitive,followed by the scanning area.The scanning area can adapt to different substructures such as subgrade,bridges and tunnels,with high comprehensive sensitivity.Originality/value–The research can provide appropriate characteristic indexes from the high-frequency radar original signal to quantitatively evaluate ballast bed condition under different substructures. 展开更多
关键词 Ballasted track Ballast bed high-frequency radar TEST Time–frequency characteristics Characteristic indexes
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Clinical value of oral contrast-enhanced ultrasonography in diagnosis of gastric tumors
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作者 Chuan-Yu Wang Xiao-Jing Fan +6 位作者 Fei-Liang Wang Yue-Yue Ge Zhao Cai Wei Wang Xin-Ping Zhou Jun Du De-Wei Dai 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第1期110-117,共8页
BACKGROUND The incidence of gastric cancer remains high,and it is the sixth most common cancer and the fourth leading cause of cancer deaths worldwide.Oral contrastenhanced ultrasonography is a simple,non-invasive,and... BACKGROUND The incidence of gastric cancer remains high,and it is the sixth most common cancer and the fourth leading cause of cancer deaths worldwide.Oral contrastenhanced ultrasonography is a simple,non-invasive,and painless method for the diagnosis of gastric tumors.AIM To explore the diagnostic value of oral contrast-enhanced ultrasonography for the detection of gastric tumors.METHODS The screening results based on oral contrast-enhanced ultrasonography and electronic gastroscopy were compared with those of the postoperative pathological examination.RESULTS Among 42 patients with gastric tumors enrolled in the study,the diagnostic accordance rate was 95.2%for oral contrast-enhanced ultrasonography(n=40)and 90.5%for electronic gastroscopy(n=38)compared with postoperative pathological examination.The Kappa value of consistency test with pathological findings was 0.812 for oral contrast-enhanced ultrasonography and 0.718 for electronic gastroscopy,and there was no significant difference between them(P=0.397).For the TNM staging of gastric tumors,the accuracy rate of oral contrast enhanced ultrasonography was 81.9%for the overall T staging and 50%,77.8%,100%,and 100%for T1,T2,T3,and T4 staging,respectively.The sensitivity and specificity were both 100%for stages T3 and T4.The diagnostic accuracy rate of oral contrast-enhanced ultrasonography was 93.8%,80%,100%,and 100%for stages N0,N1-N3,M0,and M1,respectively.CONCLUSION The accordance rate of qualitative diagnosis by oral contrast-enhanced ultrasonography is comparable to that of gastroscopy,and it could be used as the preferred method for the early screening of gastric tumors. 展开更多
关键词 Oral contrast-enhanced ultrasonography Gastric tumor Electronic gastroscopy Controlled study Pathological examination DIAGNOSIS
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Dynamic ultrasonography for optimizing treatment position in superior mesenteric artery syndrome:Two case reports and review of literature
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作者 Nobuaki Hasegawa Akihiko Oka +4 位作者 Muyiwa Awoniyi Yuri Yoshida Hiroshi Tobita Norihisa Ishimura Shunji Ishihara 《World Journal of Gastroenterology》 SCIE CAS 2024年第5期499-508,共10页
BACKGROUND Superior mesenteric artery(SMA)syndrome is a rare cause of duodenal obstruction by extrinsic compression between the SMA and the aorta(SMA-Ao).Although the left lateral recumbent position is considered effe... BACKGROUND Superior mesenteric artery(SMA)syndrome is a rare cause of duodenal obstruction by extrinsic compression between the SMA and the aorta(SMA-Ao).Although the left lateral recumbent position is considered effective in the treatment of SMA syndrome,individual variations in the optimal patient position have been noted.In this report,we present two elderly cases of SMA syndrome that exhibited rapid recovery due to ultrasonographic dynamic evaluation of the optimal position for each patient.CASE SUMMARY Case 1:A 90-year-old man with nausea and vomiting.Following diagnosis of SMA syndrome by computed tomography(CT),ultrasonography(US)revealed the SMA-Ao distance in the supine position(4 mm),which slightly improved in the lateral position(5.7–7.0 mm)without the passage of duodenal contents.However,in the sitting position,the SMA-Ao distance was increased to 15 mm accompanied by improved content passage.Additionally,US indicated enhanced passage upon abdominal massage on the right side.By day 2,the patient could eat comfortably with the optimal position and massage.Case 2:An 87-year-old woman with vomiting.After the diagnosis of SMA syndrome and aspiration pneumonia by CT,dynamic US confirmed the optimal position(SMA-Ao distance was improved to 7 mm in forward-bent position,whereas it remained at 5 mm in the supine position).By day 7 when her pneumonia recovered,she could eat with the optimal position.CONCLUSION The optimal position for SMA syndrome varies among individuals.Dynamic US appears to be a valuable tool in improving patient outcomes. 展开更多
关键词 Superior mesenteric artery syndrome Wilkie’s syndrome Cast syndrome Aorto-mesenteric compass syndrome ultrasonography Case report
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Point of care ultrasonography as the new“Laennec Sthetoscope”
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作者 Ernesto Sabath 《World Journal of Nephrology》 2024年第1期6-8,共3页
Point of care ultrasonography(POCUS)has evolved to become the fifth pillar of the conventional physical examination,and use of POCUS protocols have significantly decreased procedure complications and time to diagnose.... Point of care ultrasonography(POCUS)has evolved to become the fifth pillar of the conventional physical examination,and use of POCUS protocols have significantly decreased procedure complications and time to diagnose.However,lack of experience in POCUS by preceptors in medical schools and nephrology residency programs are significant barriers to implement a broader use.In rural and low-income areas POCUS may have a transformative effect on health care management. 展开更多
关键词 Point-of care ultrasonography Central venous catheter Internal medicine Obstetric emergencies Medical training
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Point-of-care ultrasonography spotlight:Could venous excess ultrasound serve as a shared language for internists and intensivists?
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作者 Anosh Aslam Khan Hasham Saeed +3 位作者 Ibtehaj Ul Haque Ayman Iqbal Doantrang Du Abhilash Koratala 《World Journal of Critical Care Medicine》 2024年第2期126-136,共11页
Point-of-care ultrasonography(POCUS),particularly venous excess ultrasound(VExUS)is emerging as a valuable bedside tool to gain real-time hemodynamic insights.This modality,derived from hepatic vein,portal vein,and in... Point-of-care ultrasonography(POCUS),particularly venous excess ultrasound(VExUS)is emerging as a valuable bedside tool to gain real-time hemodynamic insights.This modality,derived from hepatic vein,portal vein,and intrarenal vessel Doppler patterns,offers a scoring system for dynamic venous congestion assessment.Such an assessment can be crucial in effective management of patients with heart failure exacerbation.It facilitates diagnosis,quantification of congestion,prognostication,and monitoring the efficacy of decongestive therapy.As such,it can effectively help to manage cardiorenal syndromes in various clinical settings.Extended or eVExUS explores additional veins,potentially broadening its applications.While VExUS demonstrates promising outcomes,challenges persist,particularly in cases involving renal and liver parenchymal disease,arrhythmias,and situations of pressure and volume overload overlap.Proficiency in utilizing spectral Doppler is pivotal for clinicians to effectively employ this tool.Hence,the integration of POCUS,especially advanced applications like VExUS,into routine clinical practice necessitates enhanced training across medical specialties. 展开更多
关键词 Point-of-care ultrasonography ULTRASOUND Venous excess ultrasound Doppler Congestion Heart failure
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Sound waves and solutions:Point-of-care ultrasonography for acute kidney injury in cirrhosis
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作者 David Aguirre-Villarreal Mario Andrés de Jesús Leal-Villarreal +2 位作者 Ignacio García-Juárez Eduardo R Argaiz Abhilash Koratala 《World Journal of Critical Care Medicine》 2024年第2期83-92,共10页
This article delves into the intricate challenges of acute kidney injury(AKI)in cirrhosis,a condition fraught with high morbidity and mortality.The complexities arise from distinguishing between various causes of AKI,... This article delves into the intricate challenges of acute kidney injury(AKI)in cirrhosis,a condition fraught with high morbidity and mortality.The complexities arise from distinguishing between various causes of AKI,particularly hemodynamic AKI,in cirrhotic patients,who experience hemodynamic changes due to portal hypertension.The term"hepatocardiorenal syndrome"is introduced to encapsulate the intricate interplay among the liver,heart,and kidneys.The narrative emphasizes the often-overlooked aspect of cardiac function in AKI assessments in cirrhosis,unveiling the prevalence of cirrhotic cardiomyopathy marked by impaired diastolic function.The conventional empiric approach involving volume expansion and vasopressors for hepatorenal syndrome is critically analyzed,highlighting potential risks and variable patient responses.We advocate for a nuanced algorithm for AKI evaluation in cirrhosis,prominently featuring point-of-care ultrasonography(POCUS).POCUS applications encompass assessing fluid tolerance,detecting venous congestion,and evaluating cardiac function. 展开更多
关键词 Point-of-care ultrasonography Bedside ultrasound CIRRHOSIS CONGESTION Acute kidney injury Congestive nephropathy
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Comprehensive review on the diagnostic strategies for esophageal tuberculosis:the role of endoscopic ultrasonography
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作者 Qi Ding Lei-Lei Zhai +1 位作者 Zi-Yi Guo Ping Yao 《Gastroenterology & Hepatology Research》 2024年第1期21-28,共8页
Esophageal tuberculosis(ET)is a relatively rare clinical condition,characterized by often atypical clinical features.The lack of specificity in diagnostic methods,such as esophagogastroduodenoscopy and various imaging... Esophageal tuberculosis(ET)is a relatively rare clinical condition,characterized by often atypical clinical features.The lack of specificity in diagnostic methods,such as esophagogastroduodenoscopy and various imaging techniques,frequently leads to misdiagnosis and inappropriate treatments.Compared to esophagogastroduodenoscopy,endoscopic ultrasonography(EUS)offers a more comprehensive examination of esophageal tuberculosis lesions,including the extent of wall layer involvement and the internal structure characteristics of the lesions.Furthermore,when necessary,endoscopic ultrasonography-guided fine-needle aspiration can be employed to acquire deeper pathological tissue,significantly aiding diagnosis.When combined with the patient’s clinical presentation,endoscopic findings,and pathological features,EUS plays a crucial role in the definitive diagnosis of ET and in the differential diagnosis process.This article meticulously reviews both national and international literature to summarize the relevant features of ET,with a focus on its appearance under EUS,and to highlight the clinical value of EUS in enhancing the diagnosis of ET and in distinguishing it from other conditions.The aim is to offer guidance for the accurate diagnosis of ET. 展开更多
关键词 esophageal tuberculosis ESOPHAGOGASTRODUODENOSCOPY endoscopic ultrasonography DIAGNOSIS differential diagnosis
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A Probe into Learners'Colligational Use of High-frequency Verbs
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作者 李新利 《海外英语》 2011年第10X期339-342,共4页
This study attempts to examine the colligational use of the high-frequency verbs DO, HAVE and BE in Chinese EFL learners'written production in the CIA (Contrastive Interlanguage Analysis) approach. Findings of the... This study attempts to examine the colligational use of the high-frequency verbs DO, HAVE and BE in Chinese EFL learners'written production in the CIA (Contrastive Interlanguage Analysis) approach. Findings of the study indicate that: Chinese learners use a much smaller variety of colligational patterns, they tend to underuse the inflected forms of these verbs in their colligations and they tend to use pronouns as the subject of these verbs. Though at advanced level, they still have difficulty with grammar in terms of tense, aspect and voice. The influence of L1 transfer, the learners'spoken style in writing, the classroom teaching and the learners'use of the avoidance strategy are thought to be the major reasons. The findings in this study may have some light to shed on the EFL teaching and research in China. 展开更多
关键词 high-frequency VERBS colligations CIA
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