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61.
《Journal de gynecologie, obstetrique et biologie de la reproduction》2015,44(5):411-418
62.
Sigita Gelman rius Sakalauskas Romanas Zykus rius Pranculis Rytis Jurkonis Irma Kuliavienė Arūnas Lukoševičius Limas Kupčinskas Juozas Kupčinskas 《World journal of gastroenterology : WJG》2020,26(38):5836-5848
BACKGROUND Degree of portal hypertension(PH) is the most important prognostic factor for the decompensation of liver cirrhosis and death, therefore adequate care for patients with liver cirrhosis requires timely detection and evaluation of the presence of clinically significant PH(CSPH) and severe PH(SPH). As the most accurate method for the assessment of PH is an invasive direct measurement of hepatic venous pressure gradient(HVPG), the search for non-invasive methods to diagnose these conditions is actively ongoing.AIM To evaluate the feasibility of parameters of endogenously induced displacements and strain of liver to assess degree of PH.METHODS Of 36 patients with liver cirrhosis and measured HVPG were included in the casecontrol study. Endogenous motion of the liver was characterized by derived parameters of region average tissue displacement signal(dantero, dretro, d RMS) and results of endogenous tissue strain imaging using specific radiofrequency signal processing algorithm. Average endogenous strain μ and standard deviation σ of strain were assessed in the regions of interest(ROI)(1 cm × 1 cm and 2 cm × 2 cm in size) and different frequency subbands of endogenous motion(0-10 Hz and 10-20 Hz).RESULTS Four parameters showed statistically significant(P 0.05) correlation with HVPG measurement. The strongest correlation was obtained for the standard deviation of strain(estimated at 0-10 Hz and 2 cm × 2 cm ROI size). Three parameters showed statistically significant differences between patient groups with CSPH, but only dretro showed significant results in SPH analysis. According to ROC analysis area under the curve(AUC) of the σROI[0…10 Hz, 2 cm × 2 cm] parameter reached 0.71(P = 0.036) for the diagnosis of CSPH; with a cut-off value of 1.28 μm/cm providing 73% sensitivity and 70% specificity. AUC for the diagnosis of CSPH for μROI[0…10 Hz, 1 cm × 1 cm] was 0.78(P = 0.0024); with a cut-off value of 3.92 μm/cm providing 73% sensitivity and 80% specificity. Dretro parameter had an AUC of 0.86(P = 0.0001) for the diagnosis of CSPH and 0.84(P = 0.0001) for the diagnosis of SPH. A cut-off value of-132.34 μm yielded 100% sensitivity for both conditions, whereas specificity was 80% and 72% for CSPH and SPH respectively.CONCLUSION The parameters of endogenously induced displacements and strain of the liver correlated with HVPG and might be used for non-invasive diagnosis of PH. 相似文献
63.
64.
Maria C. Chammas Andre C. Oliveira Mario J. D´Ávilla Pedro H. Moraes Marcelo Straus Takahashi 《Ultrasound in medicine & biology》2019,45(1):50-55
We prospectively evaluated the effectiveness of contrast-enhanced ultrasonography (CEUS) for differentiation of benign versus malignant portal vein thrombosis (PVT). We studied a total of 43 patients with chronic liver disease, hepatocellular carcinoma-suggestive nodules and confirmed PVT, in whom the nature of the PVT was confirmed by follow-up imaging (US, computed tomography and/or magnetic resonance imaging) performed up to 6 mo after CEUS. PVT was assessed by US, Doppler US and CEUS with respect to vessel wall disruption and/or invasion, color Doppler vascularization, pulsed Doppler vascularization pattern and CEUS enhancement and vascularization pattern, and thrombi were classified as benign or malignant based on these findings. Follow-up studies revealed malignant PVT in 22 of the 43 patients (51%) and benign PVT in 21 patients (49%). CEUS findings were consistent with follow-up studies in 41 of the 43 patients (95%), with κ?=?0.903 (p < 0.0001), sensitivity?=?91% and specificity?=?100%, indicating that CEUS can be confidently used to differentiate benign from malignant portal vein thrombosis in the setting of chronic liver disease. 相似文献
65.
目的:基于中医传承软件系统探讨国医大师治疗心悸的用药规律。方法:收集整理《国医大师验案良方·心脑卷》中治疗心悸的病案并录入中医传承辅助平台,采用规则分析、改进互信息法、复杂系统熵聚类等数据挖掘方法,统计分析其中的用药规律。结果:分析纳入的83个病案得出149味中药,所用中药性味多为甘温,主要归心、肺、脾三经,包括丹参、黄芪、炙甘草、麦冬等高频次中药。提取置信度为1的丹参,五味子→麦冬组合,可窥见生脉饮的雏形并衍生出10个新方,新方可分为五类,分别为行气化痰类、滋阴养血类、温通心阳类、益气活血类和化痰祛瘀类。结论:国医大师治疗心悸有规律可循,主要以“益气通阳”“养阴补血”“化痰祛瘀”为组方规律,标本并治。 相似文献
66.
67.
目的通过检索特殊食品信息查询平台公布的具有缓解视疲劳功能的保健食品信息资料,以及药智数据网的中成药处方数据库中眼科中成药中有保健功能的产品信息资料,为具有缓解视疲劳功能的保健产品的组方与产品开发提供依据与参考。方法运用Microsoft Excel2016软件及中医传承辅助平台对检得的产品信息进行统计,分析其配方特点。结果共收集到141个具有缓解视疲劳功能的保健食品,其中64个(45.4%)保健食品配方中含有中药类原料。使用频次≥5的中药原料有6味,累计使用145次(72%),由高到低分别是菊花、枸杞子、决明子、桑椹、熟地黄、茯苓。通过无监督的熵层次聚类得到3个新处方。非中药原料在缓解视疲劳功能的保健食品中应用较为普遍,含有外来天然植物资源的60个产品,含叶黄素及维生素类的17个。统计眼科中成药中有保健功能的产品可知,使用频次≥4的中药原料有7味,累计使用32次(29%),由高到低分别是枸杞子、决明子、菟丝子、熟地黄、菊花、五味子、车前子。通过无监督的熵层次聚类得到1个新处方。结论保健食品在中药原料的选择上与中医药理论治疗视疲劳的原则基本契合,即滋补肝肾、平肝明目。但二者在中药原料选择范围、原料配伍、剂型种类等方面有所不同。此外,还在辨证保健理论指导下,尝试探讨应用文献数据处理统计方法筛选新配方、开发新产品,为中药复方保健产品的研发开辟了新思路、新方法。 相似文献
68.
69.
目的 探讨ArcCHECK系统在食管癌断层治疗旋转照射和固定野照射计划验证中的应用,总结相关经验。方法 对32例不同部位食管癌分别制作Helical旋转照射和Direct固定野照射验证计划,并通过ArcCHECK测量、分析,对比验证结果通过率。分析靶体积与计划验证通过率的相关性。将靶体积较小的治疗验证计划分别放在ArcCHECK模体中心和外周探测点处,分析验证通过率差异。结果 Helical计划验证通过率高于Direct计划(P<0.01),其靶体积与验证通过率的相关系数分别为-0.364和-0.042,P值分别为0.041和0.819。Helical计划采用3%/2mm标准时,高剂量区放在模体中心和外周探测点处测得的通过率不同(P=0.005),后者通过率更高;采用3%/3mm标准时与Direct计划的3%/3m、3%/2mm标准的相近(P均>0.05)。结论 Helical计划验证通过率普遍高于Direct计划,原因可能与ArcCHECK探测器的角度响应以及因更多参考点受到低剂量辐射而未参与计算有关,另外还可能跟Direct计划对断层治疗剂量控制系统要求更高有关。在Helical验证计划中,当采用3%/3mm标准时,靶体积越大,验证时出现较低通过率的可能性增加,但相关系数较低。验证计划的高剂量区位于模体中心或者探测点处都可以实现计划验证,综合考量建议放在模体等中心处。 相似文献
70.
Shinji Naganawa Rintaro Ito Hisashi Kawai Toshiaki Taoka Tadao Yoshida Michihiko Sone 《Magnetic resonance in medical sciences》2020,19(4):375
Purpose:It has been reported previously that intravenously administered gadolinium-based contrast agent (GBCA) leaks into the subarachnoid space around the cortical veins at 4 h after injection in all old people over 37 years, but not in younger people up to 37 years of age in 3D-real IR images. The purpose of this study was to investigate whether there was a strict threshold of 37 years of age for the leakage of the GBCA into the subarachnoid space.Methods:The subjects included 190 patients, that were scanned for 3D-real IR images at 4 hours after intravenous injection of GBCA as a diagnostic test for endolymphatic hydrops. The patient’s age ranged from 14 to 81 years. Two experienced neuroradiologists evaluated the images to determine whether the GBCA leakage around the cortical veins was positive or negative. Any discrepancies between the two observers were discussed and a consensus was obtained.A Mann–Whitney U test and receiver operating characteristic (ROC) curve analysis were used to compare the positive and the negative group and to set the age cut-off value for the prediction of GBCA leakage.Results:The GBCA leakage around the cortical veins was negative in 35 patients and positive in 155 patients. The average age was 33 ± 11 years in the negative group, and 55 ± 12 years in the positive group (P < 0.01). In the ROC analysis for the age and leakage of the GBCA, an area under the curve was 0.905 and the cut-off age was 37.317 years (sensitivity of 0.942 and specificity of 0.771).Conclusion:Intravenously administered GBCA leaks into the subarachnoid space around the cortical veins in most patients over 37 years of age. However, it should be noted that it can be found occasionally in patients under 37 years of age. 相似文献