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排序方式: 共有9070条查询结果,搜索用时 31 毫秒
1.
目的:探讨磁共振动态增强在早期乳腺癌影像诊断中的临床效果及检出率观察。方法:将2015年8月-2020年8月间于我院经临床检查后疑似早期乳腺癌患者100例作为研究对象,对所有患者实施超声检查以及磁共振动态增强检查,将检查结果与病理诊断结果相比较,分析磁共振动态增强扫描的检查准确率。结果:磁共振动态增强扫描于100例患者中诊断出早期乳腺癌66例,良性病变34例,准确度为94%。结论:磁共振动态增强在早期乳腺癌诊断中的准确度较高,可有效提高该病症检出率,为后续治疗方案和治疗方法的选择提供有效参考。 相似文献
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《Gait & posture》2022
ObjectiveThe aim of this study was to determine whether there is a difference in postural control between nulligravida women and women who have given birth by vaginal or cesarean section.MethodsWomen who had only vaginal delivery in the previous 1–3 years were included in the vaginal delivery group (n = 27), those who had only cesarean delivery in the previous 1–3 years were included in the cesarean section group (n = 28), and those who had never given birth were included in the control group (n = 32). Evaluations were administered 6–8 days after the ovulation phase. Postural control of the participants was evaluated with the computerized dynamic posturography device.ResultsA total of 87 women with a mean age of 29.4 ± 4 years and a mean body mass index of 24.1 ± 3.1 kg/m2 were included in the study. Antero-posterior somatosensory organization test values of the vaginal delivery group were lower than the control group (p = 0.0016). The cesarean delivery group had statistically lower antero-posterior somatosensory (p < 0.001 and p = 0.0013) and medio-lateral somatosensory (p = 0.002 and p = 0.017, respectively) test scores compared to the control group and the vaginal delivery group.ConclusionsIt was observed that women who birthed with vaginal or cesarean delivery had impaired somatosensory postural control. There is definitely a need for further studies with a long-term follow-up examining the effects of postural control during pregnancy and the postpartum period. 相似文献
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目的:探讨颈动脉高分辨率MRI(HR-MRI)血管壁成像和超声对鉴别诊断脑卒中患者颈动脉狭窄原因的效果。方法:连续纳入2018年06月-2020年12月清远市人民医院神经内科诊断为脑卒中的患者31例,均行颈部辨血管壁HR-MRI检查、超声颈动脉以及数字减影血管造影术(DSA)检查。比较不同检查方式对颈动脉狭窄原因检出情况,并采用Kappa检验分析HR-MRI与DSA、超声与DSA诊断结果的一致性。结果:DSA、超声、HR-MRI对动脉硬化的检出率比较差异无统计学意义(P>0.05)。HR-MRI对动脉夹层的检出率高于超声,差异有统计学意义(P<0.05)。超声检查未见异常占比22.6%,DSA、HR-MRI检查未见异常均为0,差异有统计学意义(P<0.05)。Kappa检验分析显示,HR-MRI诊断颈动脉狭窄原因与DSA的一致性良好(Kappa值=0.669,P<0.05)。超声诊断颈动脉狭窄原因与DSA的一致性较差(Kappa值=0.221,P<0.05)。结论:高分辨率MRI血管壁成像技术对脑卒中患者颈动脉狭窄原因的鉴别诊断效果优于超声,可作为临床诊治补充检查首选方式。 相似文献
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《Journal of vascular and interventional radiology : JVIR》2022,33(9):1073-1082.e2
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
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《Journal of vascular and interventional radiology : JVIR》2022,33(9):1034-1044.e29
PurposeTo assess the safety and tolerability of a vandetanib-eluting radiopaque embolic (BTG-002814) for transarterial chemoembolization (TACE) in patients with resectable liver malignancies.Materials and MethodsThe VEROnA clinical trial was a first-in-human, phase 0, single-arm, window-of-opportunity study. Eligible patients were aged ≥18 years and had resectable hepatocellular carcinoma (HCC) (Child-Pugh A) or metastatic colorectal cancer (mCRC). Patients received 1 mL of BTG-002814 transarterially (containing 100 mg of vandetanib) 7–21 days prior to surgery. The primary objectives were to establish the safety and tolerability of BTG-002814 and determine the concentrations of vandetanib and the N-desmethyl vandetanib metabolite in the plasma and resected liver after treatment. Biomarker studies included circulating proangiogenic factors, perfusion computed tomography, and dynamic contrast-enhanced magnetic resonance imaging.ResultsEight patients were enrolled: 2 with HCC and 6 with mCRC. There was 1 grade 3 adverse event (AE) before surgery and 18 after surgery; 6 AEs were deemed to be related to BTG-002814. Surgical resection was not delayed. Vandetanib was present in the plasma of all patients 12 days after treatment, with a mean maximum concentration of 24.3 ng/mL (standard deviation ± 13.94 ng/mL), and in resected liver tissue up to 32 days after treatment (441–404,000 ng/g). The median percentage of tumor necrosis was 92.5% (range, 5%–100%). There were no significant changes in perfusion imaging parameters after TACE.ConclusionsBTG-002814 has an acceptable safety profile in patients before surgery. The presence of vandetanib in the tumor specimens up to 32 days after treatment suggests sustained anticancer activity, while the low vandetanib levels in the plasma suggest minimal release into the systemic circulation. Further evaluation of this TACE combination is warranted in dose-finding and efficacy studies. 相似文献
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为了在腰椎退变性疾病保守治疗和融合手术中间地带寻找一种有效的预防与辅助相结合的微创治疗方式,通过对比目前常用的几种腰椎棘突间动态稳定系统的临床疗效观察和优缺点,以及对腰椎棘突间的生理结构、生物力学和相关数据的分析,在充分了解记忆合金材质的基础上,自行设计研究一种记忆合金材料的新型腰椎棘突间动态固定装置,既能重建腰椎的正常生物力学特性,满足人体脊柱的正常活动,又避免对原有结构的破坏,减少术后并发症的发生,同时也可以优化目前的治疗方法。通过研究,腰椎棘突间记忆合金动态稳定装置在理论上效果满意,可以解决现有技术的不足,优于目前的几种腰椎棘突间动态稳定系统。 相似文献
8.
Daniëlle van Dorth Krishnapriya Venugopal Dirk H. J. Poot Lydiane Hirschler Jeroen de Bresser Marion Smits Juan A. Hernandez-Tamames Clément S. Debacker Matthias J. P. van Osch 《NMR in biomedicine》2022,35(5):e4653
Dynamic susceptibility contrast (DSC) MRI is clinically used to measure brain perfusion by monitoring the dynamic passage of a bolus of contrast agent through the brain. For quantitative analysis of the DSC images, the arterial input function is required. It is known that the original assumption of a linear relation between the R2(*) relaxation and the arterial contrast agent concentration is invalid, although the exact relation is as of yet unknown. Studying this relation in vitro is time-consuming, because of the widespread variations in field strengths, MRI sequences, contrast agents, and physiological conditions. This study aims to simulate the R2(*) versus contrast concentration relation under varying physiological and technical conditions using an adapted version of an open-source simulation tool. The approach was validated with previously acquired data in human whole blood at 1.5 T by means of a gradient-echo sequence (proof-of-concept). Subsequently, the impact of hematocrit, field strength, and oxygen saturation on this relation was studied for both gradient-echo and spin-echo sequences. The results show that for both gradient-echo and spin-echo sequences, the relaxivity increases with hematocrit and field strength, while the hematocrit dependency was nonlinear for both types of MRI sequences. By contrast, oxygen saturation has only a minor effect. In conclusion, the simulation setup has proven to be an efficient method to rapidly calibrate and estimate the relation between R2(*) and gadolinium concentration in whole blood. This knowledge will be useful in future clinical work to more accurately retrieve quantitative information on brain perfusion. 相似文献
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《Ophthalmology》2023,130(8):844-853
10.
目的 探讨实施空气细菌监测对维护和管理洁净手术部空气质量的意义。方法 对某院洁净手术部的45间手术间进行沉降菌静态、动态空气监测。参照《医院洁净手术部建筑设计规范》GB 50333进行静态空气监测,参照《医院洁净手术部污染控制规范》DB/11408—2007要求进行动态空气监测。其中动态空气监测选择第一台手术不同时间段(手术切皮时、手术2 h或缝合结束、接台-麻醉-皮肤消毒时)进行采样,记录手术过程中可能影响室内空气质量的相关因素。遇动态、静态空气监测合格率较低时即查找原因,制定并实施管理措施。结果 2010年5月—2021年9月静态空气采样共782间次,合格763间次,合格率97.57%。其中2018年6月静态空气采样6间,合格率为33.33%,针对不合格情况进行原因分析,采取整改措施, 2018年11月—2021年9月静态空气监测合格率为99.48%。动态空气监测结果显示,2010年5月不同级别手术间动态空气监测结果均不合格, 2010年6月—2011年6月,共进行空气动态采样103台次,Ⅰ、Ⅱ、Ⅲ级手术间合格率分别为90.00%、89.80%、95.45%。Ⅱ、Ⅲ级手术间不同位置回风口菌落数比较,进门处回风口菌落数均高于内侧回风口,差异均有统计学意义(均P<0.05)。Ⅰ、Ⅱ、Ⅲ级手术间不同时段动态空气采样菌落数比较,差异均有统计学意义(均P<0.001),且各级手术间菌落数均随手术进程而逐渐增加。结论 洁净手术室静态、动态空气监测对维护和管理洁净手术部空气质量起到很好的督促作用;进行动态空气监测可及时掌握运行状态手术部细菌污染状况。 相似文献