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1.
《Journal of vascular and interventional radiology : JVIR》2020,31(12):2033-2042.e1
PurposeTo examine predictors of midterm occlusion in portal and hepatic veins within or adjacent to the ablation zone after irreversible electroporation (IRE) of liver tumors.Materials and MethodsThis retrospective cohort analysis included 39 patients who underwent CT-guided IRE of liver tumors. Vessels within or adjacent to the ablation zone were identified on CT images acquired immediately after the procedure, and the positional relationships with the ablation zone (within/adjacent), locations (proximal/distal), and diameters (< 4 mm or ≥ 4 mm) were evaluated. Using contrast-enhanced follow-up scans, each vessel was classified as patent, stenosed, or occluded. Associations between vessel occlusion and each variable were investigated.ResultsOverall, 33 portal veins and 64 hepatic veins were analyzed. Follow-up scans showed occlusion in 12/33 (36.7%) portal veins and 17/64 (26.6%) hepatic veins. Vessels within the ablation zone were occluded significantly more frequently than vessels adjacent to the ablation zone (portal: 55.6% [10/18] vs 13.3% [2/15], P = .04; hepatic: 45.4% [15/33] vs 6.4% [2/31], P = .011). Vessels with a diameter < 4 mm were also occluded significantly more frequently than vessels with a diameter ≥ 4 mm (portal: 72.7% [8/11] vs 18.1% [4/22], P = .011; hepatic: 54.8% [17/31] vs 0% [0/33], P < .001). The respective positive and negative predictive values for occlusion of vessels categorized as both within and < 4 mm were 88% (7/8) and 82% (20/25) for portal veins and 79% (15/19) and 96% (43/45) for hepatic veins.ConclusionsMidterm vessel occlusion after liver IRE could be predicted with relatively high accuracy by assessing ablation location and vessel diameter. 相似文献
2.
目的调查门诊和普通病房电脑鼠标不同时段的细菌污染情况。方法随机抽取某院门诊及普通病房的各16个电脑鼠标,分别于8∶00、10∶30、13∶00、15∶30进行采样,样本接种培养后对菌落计数并筛查多重耐药菌。结果32个鼠标共计采样128次,最高菌落数达121 CFU/cm2,平均菌落数为23.9 CFU/cm2。随着时间的推移,同一鼠标的细菌计数逐渐增多。不同时段门诊和病房的电脑鼠标菌落数比较,在10∶30、13∶00、15∶30三个时间点,病房鼠标的菌落数均高于门诊(均P≤0.05)。64个病房电脑鼠标标本中检出耐甲氧西林金黄色葡萄球菌(MRSA)和耐碳青霉烯类鲍曼不动杆菌(CRAB)各1株。结论加强鼠标日常清洁消毒及监测工作非常重要,应增加清洁消毒频率或更换长效消毒剂,加强病房环境的清洁消毒。 相似文献
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冠状病毒(coronavirus,CoVs)感染主要累及肺部,但对心血管系统损伤作用也不容忽视。CoVs感染引起的心脏损伤并非罕见,其发生与病情的严重程度密切相关。本文首先从CoVs引起心血管损伤的证据入手,进一步探讨了CoVs对心肌的直接损伤,以及肾素血管紧张素(RAS)系统激活和细胞因子风暴与炎症反应对心血管损伤的可能作用机制。相关心血管损伤的可能机制包括,(1)病毒直接作用:CoVs在心肌细胞复制,损伤心肌;(2)RAS系统激活:感染CoVs后,心脏血管紧张素转化酶2(angiotensin-converting enzyme 2,ACE2)的表达下调,激活RAS系统,使得血管紧张素Ⅱ(AngiotensinⅡ,AngⅡ)收缩血管功能增强,Ang1-7保护心脏效应减弱;(3)诱发细胞因子风暴:循环细胞因子和全身炎症反应引起心脏损伤;(4)其他:包括低氧血症和儿茶酚胺心脏毒性。本文就相关内容作一综述,为后续的详尽机制和治疗策略研究提供思路。 相似文献
5.
《The journal of sexual medicine》2020,17(8):1423-1433
BackgroundProstatic radiation therapy (RT) often causes erectile dysfunction (ED) and the mechanisms governing RT-induced ED are unclear with a lack of therapeutic strategies.AimTo determine the effects of ex vivo RT on major pelvic ganglion (MPG) neuron survival, and neurite growth in whole vs dissociated culture.MethodsMPGs were removed and irradiated (0 or 8 Gy) from male Sprague Dawley rats. For dissociated culture, MPG neurons were digested in collagenase/dispase and cultured on coverslips. Immunofluorescent staining for beta-tubulin III (TUBB3; neuron marker), neuronal nitric oxide synthase (nNOS; nitrergic marker), tyrosine hydroxylase (TH; sympathetic marker), and terminal deoxynucleotidyl transferase dUTP nick end labeling assessed neurite length, branching, autonomic neuron density, and apoptosis. For whole organ culture, MPGs were grown in Matrigel. Gene expression of apoptotic markers (caspase 1, 3), TUBB3, nNOS, TH, and Schwann cells (Sox10, Krox20, glial fibrillary acid protein) was measured in whole organ cultured MPGs by quantitative polymerase chain reaction.OutcomesAfter 72 hours, neurite length, branching, autonomic neuron density, and apoptosis were assessed, and gene expression was measured.ResultsRT increased apoptosis in dissociated neurons measured by terminal deoxynucleotidyl transferase dUTP nick end labeling (P < .001) and whole MPG culture via upregulation of caspase 3 gene expression (P < .05). Nitrergic neurons were markedly decreased in irradiated dissociated culture (P < .05), while nNOS gene expression was upregulated in irradiated whole organ culture (P < .05). The proportion of dissociated sympathetic neurons and whole organ TH gene expression remained unchanged after RT. Interestingly, RT dissociated neurites were 22% shorter than controls, while RT whole organ neurites were 15% longer than controls (P < .01). MPG Schwann cells markers (Sox10, Krox20) were elevated after RT in whole organ culture.Clinical TranslationProstatic RT leads to increased neuronal cell death and less erectogenic nitrergic neurons contributing to ED.Strengths & LimitationsThe advantages of dissociated neuron culture include distinct neurites which are easily measured for apoptosis, length/branching, and specific neuron types. In contrast, whole MPG culture is advantageous as it contains all the supporting cells present in vivo.ConclusionThe 2 different culture methods demonstrated opposing neurite growth after RT indicating the importance of supporting cell network to promote pelvic neuron neuritogenesis and survival following RT.Randolph JT, Pak ES, Koontz BF, et al. Ex Vivo Radiation Leads to Opposing Neurite Growth in Whole Ganglia vs Dissociated Cultured Pelvic Neurons. J Sex Med 2020;17:1423–1433. 相似文献
6.
目的 评价NITI悬臂梁在矫正舌倾下颌磨牙中的临床效果。方法 选择16例单侧下颌第二磨牙舌倾的病例为研究对象,带垫铸造支架连接双侧下颌后牙,提供颌内支抗、解除咬合锁结,0.018英寸×0.025英寸或0.019英寸×0.025英寸NITI悬臂梁提供颊向旋转力矩和压低力。采用Graphpad Prism 6.0 软件对治疗前、后所测数据进行配对 t 检验。结果 所有患牙均获得直立,牙轴变化24°±1.2°(P<0.01),近中舌尖到正中矢状面垂直距离变化(3±0.8) mm(P<0.05),牙周状况良好,咬合关系稳定。结论 铸造支架联合NITI 悬臂梁可提供有效力学机制,矫正舌倾下颌磨牙。 相似文献
7.
IntroductionRates of aneurysm occlusion with the pipeline embolization device (PED) has varied widely in the literature from 55.7% to 93.3% at 6 months, which may reflect a difference in technique including sizing and number of devices used.Methods140 cases at our institution were retrospectively reviewed, and aneurysms treated with a single PED vs. multiple were compared.ResultsComplete aneurysm occlusion was achieved in 86.9% at 6 months, 91.8% at 1 year, and 97.6% at longest follow-up. Retreatment with an additional device was required in 7 (5.1%). Major and minor complication rate within 30 days was 1.4% and 5.0%, and at greater than 30 days was 0.8% and 3.1%.Patients treated with multiple PEDs had significantly higher rates of aneurysm occlusion at 6 months (92.9% vs. 75.6%, p = 0.017) and 12 months (98.4% vs. 81.1%, p = 0.014), with no difference in complications. The two groups were similar aside from a higher number of ophthalmic and paraophthalmic aneurysms treated with multiple PEDs (23.4% vs. 6.5%, p = 0.004; and 35.1% vs. 17.4%, p = 0.020), and more posterior communicating artery and recurrent aneurysms treated with a single PED (28.3% vs. 3.2%, p = 0.001; 23.9% vs. 8.5%, p = 0.031). The use of multiple PEDs was found to be an independent predictor of aneurysm occlusion in a multivariate analysis (p = 0.015).ConclusionsThe use of multiple PEDs for intracranial aneurysms leads to significantly higher occlusion rates without added morbidity. This benefit is particularly appropriate for ophthalmic segment aneurysms, while more distal segments with eloquent perforating branches should be managed with caution. 相似文献
8.
超顺磁性氧化铁标记大鼠骨髓基质细胞经门静脉移植MRI活体示踪的研究 总被引:9,自引:0,他引:9
目的观察1.5T场强MRI联合动物专用线圈是否可以活体示踪经门静脉移植的纳米级超顺磁性氧化铁颗粒标记的骨髓基质细胞(bone marrow stromal cells BMSCs),为介人性门静脉骨髓基质细胞移植治疗终末期肝脏疾病的研究提供进一步的依据。方法供体大鼠5只,梯度密度离心分离BMSCs,纳米级超顺磁性氧化铁颗粒和脂质体转染BMSCs,体外经普鲁士蓝染色和HE染色确定细胞标记率。受体大鼠15只,分为5组,分别为对照组和纳米级超顺磁性氧化铁颗粒标记的骨髓基质细胞经门静脉移植人正常大鼠肝脏后2h、3d、7d及2周组。1.5T场强MRI联合动物专用线圈行T1W、T2W和T2*序列扫描,观察肝脏信号改变情况,与对照组比较,并且与组织切片对照。结果纳米级超顺磁性氧化铁颗粒和脂质体转染BMSCs,细胞标记率〉95%。经门静脉移植人正常大鼠肝脏后,T2*序列扫描显示经标记的BMSCs在肝内显示弥漫性的结节性低信号影,移植后2h到2周均可见到细胞在受体肝脏内存在,组织学切片显示信号缺失部位与铁颗粒标记细胞相一致。结论纳米级超顺磁性铁氧体颗粒标记的大鼠BMSCs经门静脉移植后可以通过1、5T场强行MRI活体示踪,为临床干细胞移植的应用提供可行的示踪方法。 相似文献
9.
积极主动为贫困人口服务--上海市北站医院平价病房的案例调查 总被引:1,自引:0,他引:1
目的:对上海市一所国有民营医院的平价病房进行案例调查,了解运行状况、经验及存在问题。方法:相关人员访谈和现场观察。结果:该院设立了14张床位的平价病房,收治对象是低保户、特困户及经济困难的外来务工人员。对医保病人和自费病人设定不同的减免优惠方案,包括减免50.0%的床位费和10.0%的护理、检查、治疗及手术等劳务费用(药费除外)。以收治急性病为主,住院时间原则上不超过2周。出院病人总费用的实际减免率约为6.0% ̄10.0%。结论:创办平价病房的方向应予肯定。是民营机构委托管理医院的一种公益性(非营利性)的表现,对其他公立医疗机构具有促进作用。 相似文献
10.
Pathways from first health care seeking to diagnosis: obstacles to tuberculosis care in rural China.
W B Wang Q W Jiang Y Chen B Xu 《The international journal of tuberculosis and lung disease》2007,11(4):386-391
OBJECTIVE: To examine health care seeking pathways for patients with tuberculosis (TB) and barriers related to these pathways in counties under the National TB Control Programme in rural China. METHODS: A cross-sectional study was conducted in two counties of east China in 2004-2005. A total of 557 TB patients were recruited and interviewed by physicians at the time of TB diagnosis. RESULTS: Of 557 participants, 13.3% had presented to a specialised county TB dispensary (CTD) directly after onset of symptoms, 31.4% had first sought care at a village health station and 51.2% had visited a township or county hospital first. The proportion of referral by a first health care provider to a CTD was highest in county level hospitals (73.5%) and lowest in village health stations (21.7%). The most prompt pathway from first health care seeking to TB diagnosis was to visit a CTD directly, with a median provider's delay of only one day. There was an increase in provider's delay when more health facilities were involved. CONCLUSION: To improve direct referral from general health care providers, especially village health care workers, to TB specialists would significantly shorten the delays in TB diagnosis in rural China. 相似文献