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1.
PurposeTo create a nonsurgical animal model of osteoarthritis (OA) to evaluate the effects of embolotherapy during geniculate artery embolization (GAE).Materials and MethodsFluoroscopy-guided injections of 700 mg of sodium monoiodoacetate were performed into the left stifle in 6 rams. Kinematic data were collected before and after induction. At 10 weeks after induction, Subjects 1 and 4–6 underwent magnetic resonance (MR) imaging with dynamic contrast enhancement (DCE) and Subjects 1, 3, and 4–6 underwent angiography with angiographic scoring to identify regions with greatest disease severity for superselective embolization (75–250-μm microspheres). Target vessel size was measured. At 24 weeks after angiography, DCE-MR imaging, angiography, and euthanasia were performed, and bilateral stifles were harvested. Medial/lateral tibial and femoral condylar, patellar, and synovial samples were cut, preserved, decalcified, and scored using the Osteoarthritis Research Society International criteria. The stifle and synovium Whole-Organ Magnetic Resonance Imaging Score and Multicenter Osteoarthritis Study score were determined. The volume transfer constant (Ktrans) and extracellular volume fraction (ve) were calculated from DCE-MR imaging along the lateral synovial regions of interest.ResultsThe mean gross and microscopic pathological scores were elevated at 38 and 61, respectively. Mean synovitis score was elevated at 9.2. Mean pre-embolization and postembolization angiographic scores were 5 and 3.8, respectively. Mean superior, transverse, and inferior geniculate artery diameters were 3.1 mm ± 1.21, 2.0 mm ± 0.50, and 1.6 mm ± 0.41 mm, respectively. Mean pre-embolization and postembolization cartilage and synovitis scores were elevated at 35.13 and 73.3 and 5.5 and 9.2, respectively. The Ktrans/ve values of Subjects 4, 5, and 6 were elevated at 0.049/0.38, 0.074/0.53, and 0.065/0.51, respectively. Altered gait of the hind limb was observed in all subjects after induction, with reduced joint mobility. No skin necrosis or osteonecrosis was observed.ConclusionsA nonsurgical ovine animal knee OA model was created, which allowed the collection of angiographic, histopathological, MR imaging, and kinematic data to study the effects of GAE.  相似文献   
2.
对比增强能谱X线摄影(contrast enhancement spectral mammography, CESM)是在普通X线检查的基础上结合血管造影剂进行检查的一种新技术,是通过注射造影剂有效消除组织重叠对病灶的遮盖,实现对肿块真实形态显示,并提供血供信息。目前临床上对CESM进行了一系列的研究,本文就CESM成像原理、对乳腺癌的诊断、应用前景几个方面进行综述。  相似文献   
3.
PurposeTo improve the efficiency and accuracy of clinicians documenting acute clinical events related to contrast agent administration using a web browser–based semistructured documentation support tool.MethodsA new tool called Contrast Incident Support and Reporting (CISaR) was developed to enable radiologists responding to contrast reactions to document inciting contrast class, type of event, severity of contrast reaction, and recommendation for future contrast use. Retrospective analysis was conducted of all CT and MRI examinations performed between February 2018 and December 2019 across our hospital system with associated contrast reaction documentation. Time periods were defined as before tool deployment, early adoption, and steady-state deployment. The primary outcome measure was the presence of event documentation by a radiologist. The secondary outcome measure was completeness of the documentation parameters.ResultsA total of 431 CT and MRI studies with reactions were included in the study, and 50% of studies had radiologist documentation during the pre-CISaR period. This increased to 66% during the early adoption period and 89% in the post-CISaR period. It took approximately 9 months from the introduction of CISaR to reach full adoption and become the main method for adverse contrast reaction documentation. The percentage of radiologist documentation that detailed provoking contrast agent class, severity of reaction, reaction type, and future contrast agent recommendation all significantly increased (P < .0001), with greater than 95% inclusion of each element.ConclusionThe implementation of a semistructured electronic application for adverse contrast reaction reporting significantly increased radiologist documentation rate and completeness of the documentation.  相似文献   
4.
目的 采用Meta分析对比四维子宫输卵管超声造影(4D-HyCoSy)与子宫输卵管造影(HSG)评估输卵管通畅性的效能。方法 系统搜索PubMed、Cochrane Library、Embase、Web of Science、中国生物医学文献数据库、中国知网、万方医学网及维普数据库中建库至今有关4D-HyCoSy和/或HSG评估输卵管通畅性的文献。由2名研究人员依据纳入标准和排除标准筛选文献并提取信息;分别计算4D-HyCoSy和HSG评估输卵管通畅性的合并敏感度(SEN)、特异度(SPE)及诊断比值比(DOR),绘制综合受试者工作特征(SROC)曲线,获得曲线下面积(AUC),并以Medcalc 19.1.1统计软件比较AUC。结果 最终纳入19篇文献、1 358例疑似输卵管因素导致不孕患者,其中4篇同时采用4D-HyCoSy及HSG评估输卵管通畅性,10篇仅以4D-HyCoSy评估,5篇仅以HSG评估。Meta分析结果显示,4D-HyCoSy评估输卵管通畅性的合并SEN、SPE及DOR分别为0.92[95%CI(0.91,0.94)]、0.91[95%CI(0.89,0.93)]及115.06[95%CI(54.23,224.10)];HSG评估输卵管通畅性的合并SEN、SPE及DOR分别为0.84[95%CI(0.81,0.87)]、0.80[95%CI(0.76,0.83)]及28.64[95%CI(10.08,81.35)]。4D-HyCoSy评估输卵管通畅性的AUC为0.98[95%CI(0.96,0.99)],HSG为0.93[95%CI(0.90,0.95)],差异有统计学意义(Z=6.97,P<0.01)。结论 4D-HyCoSy评估输卵管通畅性的效能高于HSG。  相似文献   
5.
This work describes a measurement method for assessing dose-related image-quality of CT scans based on the difference detail curve (DDC) method, and showcases its use in a low contrast setting. The method is based on a phantom consisting of elliptical slices of different sizes into which contrast object modules can be inserted. These modules contain contrast objects based on (synthetic) resin mixtures with sucrose (native) or sodium iodine (contrast medium). Mixing ratios are provided to achieve a range of clinically relevant CT-numbers with these materials. The phantom is characterized in terms of contrast accuracy, energy dependency and long-term drift with satisfying results. Contrast accuracy and energy dependency are similar to that of water or soft tissue. Image quality of 655 scans of the phantom acquired at 30 different clinical institutions and with 16 different CT scanner models from 4 manufacturers was assessed by calculating a difference detail curve (DDC) from evaluation of up to 5 human observers using a custom-made software (RadiVates) described in this work. Based on these measurements, inter-observer variability was quantified using a bootstrap method and was shown to be a large contributor to the overall variability. This work demonstrates that assessment of CT image quality is feasible with the aforementioned phantom and DDC method.  相似文献   
6.
目的研究鸦胆子油软胶囊联合SOX方案(奥沙利铂+替吉奥)治疗晚期结直肠癌的临床疗效。方法选取2018年8月-2019年8月在郑州大学附属洛阳中心医院治疗的80例晚期结直肠癌患者,所有患者随机分为对照组和治疗组,每组各40例。对照组患者入院后给予SOX方案治疗,第1~14天给予注射用奥沙利铂,推荐剂量130 mg/m^2,溶于500 mL 5%葡萄糖溶液中,输注时间小于3h;第1~21天口服替吉奥胶囊,1粒/次,2次/d。治疗组在对照组基础上口服鸦胆子油软胶囊,4粒/次,3次/d。21 d为1个治疗疗程,两组患者接受治疗3个疗程。观察两组的临床疗效,比较Karnofsky(KPS)评分、生活质量(QOL)评分及血清癌胚抗原(CEA)、基质金属蛋白酶(MMP)-2和MMP-9水平。结果经过治疗后,治疗组客观缓解率(ORR)和疾病控制率(CBR)显著高于对照组(P<0.05)。治疗后,两组患者KPS评分和QOL评分显著升高(P<0.05),且治疗组KPS评分和QOL评分升高程度较大(P<0.05)。治疗后,两组CEA、MMP-2和MMP-9水平显著降低(P<0.05);并且治疗组降低较多(P<0.05)。治疗组胃肠道反应、血小板减少、白细胞减少和转氨酶升高等不良反应发生率明显低于对照组(P<0.05)。结论鸦胆子油软胶囊联合SOX方案治疗晚期结直肠癌具有较好的治疗效果,能够提高患者生活质量,降低肿瘤标志物水平,安全性较高,值得在临床上推广应用。  相似文献   
7.
目的探讨不同程度碘对比剂后急性肾损伤的危险因素及其转归预后。方法筛选2016年4月1日至2019年8月31日于重庆医科大学附属第三医院住院期间发生碘对比剂后急性肾损伤(PC-AKI)的患者,按照急性肾损伤分层标准将其分为非严重损伤组(A组)和严重损伤组(B组),从基本人口学资料、基础疾病、药物使用情况、转归预后等方面分析两组患者的特点及差异。结果 1 920例患者中发生PC-AKI者90例,其中A组72例(80.00%),B组18例(20.00%),B组中最终需肾脏替代治疗(血液透析)干预者11例(12.22%)。A组与B组间一般情况、基础肾功能、碘对比剂的使用以及联用肾毒性药物、静脉水化量等观察指标无统计学差异。B组合并慢性疾病者更多,其中冠心病(55.56%vs 29.17%)、心肌梗死(27.78%vs 5.56%)患病率差异具有统计学意义(P<0.05),行血液透析的患者第一诊断为心肌梗死者占45.45%。65.85%的患者在使用对比剂后10 d内肌酐仍高于基线,54.54%的透析患者在出院时仍需透析治疗,81.81%的透析患者出院时死亡或放弃治疗。结论合并冠心病、心肌梗死的患者更容易发生严重PC-AKI,当合并这些疾病的患者使用碘对比剂时,临床医师应密切关注其肾功能的变化。PC-AKI的肾功转归较差,发生PC-AKI后需透析治疗的患者往往预后不良。  相似文献   
8.
目的探讨冬虫夏草预防糖尿病大鼠对比剂肾病的机制。方法SD大鼠80只,腹腔注射链脲佐菌素(60 mg/kg)建立糖尿病模型,并随机分为对照组(C组)、对比剂肾病组(CIN组)、冬虫夏草低剂量组(L组)、冬虫夏草标准剂量组(M组)和冬虫夏草强化剂量组(H组)。L组、M组、H组大鼠分别给予冬虫夏草(2.0、2.5、3.0 g/kg)灌胃,C组、CIN组则以等量生理盐水灌饲,连续7天。7天后检测SCr、BUN、尿蛋白排泄率(UAE)、一氧化氮(NO)、超氧化物歧化酶(SOD)、丙二醛(MDA)、总抗氧化能力(T-AOC)、中性粒细胞明胶酶相关脂质运载蛋白(NGAL)、肾损伤分子1(KIM-1)及IL-18。取左肾测病理和氧化应激指标;右肾用于Western Blot检测抗凋亡蛋白和促凋亡蛋白(包括:Bcl-2、Bax、Caspase-3、Caspase-9、p-Akt、p-mTOR、p-ERK、p-JNK、p-P70S6K)表达。结果与C组比较,CIN组SCr、BUN、UAE、MDA、NAGL、KIM-1、IL-18均明显升高,NO、T-SOD降低(P<0.05)。与CIN组比较,L组、M组、H组SCr、BUN、UAE、MDA均明显降低,NO、T-SOD升高(P<0.05);L组、H组NAGL、IL-18、降低(P<0.01),其中H组KIM-1均明显降低(P<0.01)。与L组、M组比较,H组SCr、BUN、UAE、MDA、NGAL、KIM-1、IL-18明显降低,NO、T-SOD升高(P<0.05)。与C组比较,CIN组Bcl-2、P-Akt、P-mTOR、P-P70S6K、P-ERK蛋白表达增加,Bax、P-JNK、Caspase-3、Caspase-9蛋白表达减少(P<0.05)。与CIN组比较,Bcl-2、P-Akt、P-mTOR、P-P70S6K、P-ERK蛋白表达在L组、M组、H组逐渐增加,其中H组最高(P<0.05),Bax、P-JNK、Caspase-3、Caspase-9蛋白表达L组、M组、H组逐渐减少,H组表达量最少(P<0.05)。结论冬虫夏草通过抗氧化应激、抑制脂质过氧化反应、抗凋亡等途径对糖尿病大鼠对比剂肾病发挥较好的保护作用,冬虫夏草强化剂量组优于低剂量组和标准剂量组。  相似文献   
9.
Intravenous leiomyomatosis (IVL) with intracardiac extension is a rare condition, which the benign tumor invades into the right heart through inferior vena cava. We described the findings of ultrasonography in eight patients with this disease. Transthoracic echocardiography (TTE) can reveal the intracardiac lesion burden and associated compromise. Contrast‐enhanced ultrasonography (CEUS) can trace the origin of the lesion and extension. Therefore, combining TTE with CEUS is used to better characterize this complex lesion and plays a crucial role in guidance of surgical decision.  相似文献   
10.
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