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1.
目的:分析无创呼吸机治疗慢性阻塞性肺疾病的临床疗效。方法:选取2019年3月~2020年12月天津市第四中心医院收治的84例慢性阻塞性肺疾病患者为研究对象,应用随机数字表法将其分为两组,组间一般资料差异无统计学意义(P>0.05)。患者入院后均给予祛痰以及解除气道痉挛等常规治疗,在此基础上对照组采用鼻导管持续低流量吸氧治疗,研究组采用无创呼吸机进行治疗。观察两组患者治疗前后肺通气功能指标和动脉血气指标,以及患者住院时间。结果:治疗前各项观察指标组间差异均无统计学意义(P>0.05)。治疗后研究组FEV1%和FEV1/FVC分别为(62.71±7.30)和(67.63±7.75)%,均显著优于对照组的(50.12±5.81)和(60.27±7.38)%(P<0.05)。治疗后研究组PaO2和PaCO2分别为(81.46±7.23)mmHg和(46.31±5.09)mmHg,均显著优于对照组的(67.70±6.44)mmHg和(58.28±6.62)mmHg(P<0.05)。同时研究组住院时间为(18.26±3.71)d,显著短于对照组的(22.65±3.84)d(P<0.05)。结论:无创呼吸机可以显著改善慢性阻塞性肺疾病患者病情。  相似文献   
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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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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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Arterial spin labeling (ASL) imaging is a powerful magnetic resonance imaging technique that allows to quantitatively measure blood perfusion non-invasively, which has great potential for assessing tissue viability in various clinical settings. However, the clinical applications of ASL are currently limited by its low signal-to-noise ratio (SNR), limited spatial resolution, and long imaging time. In this work, we propose an unsupervised deep learning-based image denoising and reconstruction framework to improve the SNR and accelerate the imaging speed of high resolution ASL imaging. The unique feature of the proposed framework is that it does not require any prior training pairs but only the subject's own anatomical prior, such as T1-weighted images, as network input. The neural network was trained from scratch in the denoising or reconstruction process, with noisy images or sparely sampled k-space data as training labels. Performance of the proposed method was evaluated using in vivo experiment data obtained from 3 healthy subjects on a 3T MR scanner, using ASL images acquired with 44-min acquisition time as the ground truth. Both qualitative and quantitative analyses demonstrate the superior performance of the proposed txtc framework over the reference methods. In summary, our proposed unsupervised deep learning-based denoising and reconstruction framework can improve the image quality and accelerate the imaging speed of ASL imaging.  相似文献   
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目的 利用三维伪连续动脉自旋标记(3D pcASL)成像技术比较阿尔茨海默病(AD)和帕金森病痴呆(PDD)病人脑灌注的异同,并分析脑灌注改变与认知功能损害的相关性。 方法 前瞻性收集AD病人24例、PDD病人26例、正常对照(NC)36例,均行颅脑常规MRI及3D pcASL灌注MRI检查。采用基于Matlab的SPM12软件对3D pcASL序列扫描获得的脑血流(CBF)图进行预处理,通过单因素协方差分析及独立样本t检验进行组间比较。利用DPABI软件提取AD组与NC组、PDD组与NC组灌注存在差异脑区的相对脑血流量(rCBF)值,采用Pearson相关方法对rCBF值与简易精神状态量表(MMSE)及蒙特利尔认知评估量表(MoCA)评分做相关性分析。 结果 与NC组相比,AD组双侧大脑皮质的广泛区域灌注减低,双侧丘脑、基底节、海马及辅助运动区(SMA)灌注增高;PDD组表现为与AD组基本一致的灌注减低和增高的脑区,但是脑区变化范围缩小。与AD组相比,PDD组双侧壳核、左侧中央前回、右侧SMA灌注减低,右侧顶下小叶灌注增高。AD组左侧额中回及左侧颞中回的灌注值与MMSE评分(分别r=0.64,P<0.001;r=0.50,P=0.01)及MoCA评分(分别r=0.44,P=0.03;r=0.48,P=0.02)均呈正相关,PDD组相关脑区与认知评分未见显著相关性。 结论 3D pcASL成像技术能够直观地反映AD与PDD病人类似的脑血流灌注模式,同时显示两者的灌注差异。AD病人多个脑区灌注值与认知相关评分呈正相关,提示脑血流改变与认知损伤具有相关性。  相似文献   
9.
Vascular injuries that occur during traffic accidents are a commonly neglected aspect that can add more detail to the framework of a case. In this study, we analysed a case series of 150 traffic accidents, 39 of which were marked by microscopically identifiable vascular lesions. The purpose was to identify the presence of carotid injuries in individuals who died due to traffic accidents and had nonpenetrating trauma of the neck. We focused on the discrepancies regarding the macroscopical aspect and the histology and demonstrated how histological analysis of the carotids in cases of trauma can reveal injuries that are attributable to the trauma itself. We conducted a histological analysis of the lesions to describe their distribution and type and investigate potential correlations. The study offers insight on how to examine road accidents that involve traumatic injury of the carotid arteries. Indeed the main task of the forensic pathologist in the case of death is to establish the existence of a causal relationship between the micro- or macroscopic alterations observed in the autopsy and the traumatic event that led to the death of the subject. Thus, further morphological elements were provided to the forensic practitioners that may reveal injuries attributable to the trauma itself and should be evaluated in cases of trauma in traffic accidents.  相似文献   
10.
BackgroundA comprehensive re-evaluation on the role of trans-arterial chemoembolization (TACE) in patients with intrahepatic cholangiocarcinoma.MethodsA thorough database searching was performed in PubMed, EMBASE, and the Cochrane Library. Eligible studies were restricted to comparative studies between TACE and non-TACE cohorts. RevMan5.3 software and Stata 13.0 software were used for statistical analyses. The primary endpoint of our study was long-term survival.ResultsA total of 11 studies with 2036 patients were finally identified. Pooled results revealed that patients receiving TACE had a significantly better overall survival (OS) versus those without TACE (P < 0.05). Subgroup analyses were performed according to different types of TACE. Prophylactic post-surgical TACE (PPTACE) was associated with a significantly better OS versus those without PPTACE (P < 0.05). Palliative TACE (PTACE) also achieved a significantly better OS compared with those with supportive treatment (ST) only (P < 0.00001). However, TACE had no impact on disease-free survival (P = 0.87) and was less effective than surgical resection (P = 0.003).ConclusionPPTACE has a remarkable impact on OS versus those with surgical resections only and should be regularly performed. Regarding patients with unresectable disease, apart from conventional ST, adjuvant PTACE is also recommended. Upcoming prospective randomized controlled trials are warranted for further validation.  相似文献   
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