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1.
A 25-year-old, emaciated man without medical treatment was found to have died suddenly at home by his mother. At autopsy, there were no injuries to his body, but significant circulatory insufficiency was observed. Electron microscopy revealed abnormal mitochondria in cells of the cardiac conduction system. The conduction system was filled with mitochondrial size abnormalities and mitochondrial cristae abnormalities. No notable abnormal findings were observed in other organs. Genetic examination of the blood revealed the mitochondrial pathogenetic variant m.3243A>G. Epileptic seizures, diabetic ketoacidosis, and hyperosmolar hyperglycemic state were unlikely to be the cause of sudden death. The cause of death was diagnosed as arrhythmia possibly induced by the failure of the cardiac conduction system due to mitochondrial disease. This is a rare case of sudden death caused by an accumulation of abnormal mitochondria in the cardiac conduction system.  相似文献   
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目的 分析m6A阅读器胰岛素样生长因子2-mRNA结合蛋白1(insulin-like growth factor 2 mRNA-binding protein 1,IGF2BP1)在肝细胞癌(hepatocellular carcinoma,HCC)中的表达水平及其对HCC患者预后的影响,并探讨IGF2BP1在HCC发生发展中的作用及其潜在机制。方法 基于5对HCC癌及相应癌旁组织mRNA-seq数据和TCGA数据库LIHC的mRNA-seq数据综合分析IGF2BP1在HCC中的表达情况,同时利用TCGA数据库中343例HCC患者的临床随访资料分析IGF2BP1表达水平对HCC患者总生存期的影响。基于TCGA数据库筛选IGF2BP1的共表达mRNA,并利用m6Avar在线网站预测mRNA的m6A位点及其RNA结合蛋白等信息,最终构建IGF2BP1的基因调控网络。结果 IGF2BP1基因在HCC中表达上调(log2FC HCC转录组数据=10.684,P<0.001;log2FC TCGA-LIHC数据集=7.032,P<0.001)。生存分析显示IGF2BP1低表达的HCC患者中位生存时间为5.84年,IGF2BP1高表达患者为4.44年,高表达患者总生存期缩短(P=0.011)。22个差异表达的mRNA与IGF2BP1存在靶向结合关系,并与其表达水平呈正相关。其中,HMGA2等15个高表达mRNA的HCC患者总生存期缩短。HMGA2、PEG10、CEP55、RHO、CDC6和KIF23基因中的潜在m6A甲基化位点位于mRNA 3'UTR端的miRNA结合区域。结论 IGF2BP1在HCC中高表达且导致患者总生存期缩短。IGF2BP1可能通过m6A甲基化及miRNA抑制作用的方式上调mRNA的表达,促进HCC发生并导致不良预后。  相似文献   
4.
This report describes a technique for measuring lung shunt fraction (LSF) twice in a single session during planning arteriography for radioembolization using low and standard dose technetium-99m macroaggregated albumin (99mTc-MAA). A patient with a 16.0 cm hepatocellular carcinoma and LSF of 70% was treated with lenvatinib for 4 weeks. Planning arteriography with administration of 0.5 millicuries of 99mTc-MAA was then performed. Arterial access was maintained while the LSF was calculated, which was persistently elevated at 54%. Embolization of arteriovenous shunts was performed during the same session and 5.0 millicuries of 99mTc-MAA were administered. The repeat LSF was 29%. Successful radioembolization was subsequently performed.  相似文献   
5.
目的 探讨甲状腺99TcmO-4 显像冷结节对不同性质甲状腺疾病的诊断价值。方法 采用静脉注射99TcmO-4 185MBq ,2 0min后甲状腺前位静态显像 ,采集总计数 1× 10 6。显像显示甲状腺结节局部放射性分布缺损或低于正常甲状腺组织则定性为冷结节。结果  34 2例甲状腺99TcmO-4 显像发现冷结节 85例 ,发生率为2 4.9% ,85例冷结节中 ,37例 (4 3.5 % )为甲状腺瘤 ,15例为甲状腺癌 (17.6 % ) ,2 0例 (2 3.5 % )为结节性甲状腺肿 ,8例 (9.4% )为甲状腺炎 ,4例 (4 .7% )为单纯性甲状腺囊肿 ,1例 (1.3% )为甲状腺外肿物。结论 冷结节在甲状腺99Tcm O-4 显像时较为常见 ,且不同性质甲状腺疾病的冷结节及其周围组织有一定的特征性表现 ,因此99TcmO-4显像冷结节对甲状腺腺瘤、甲状腺癌、甲状腺囊肿、甲状腺炎等常见疾病具有较高的临床价值。  相似文献   
6.
Considering that the 1.32-μm Nd-YAG laser should have physicothermal properties close to those of the CO2 laser, a series of experiments were conducted on rat cortex (N = 51). Three laser wavelengths were compared: CO2 laser (10.6 μm), 1.06-μm Nd-YAG, and 1.32-μm Nd-YAG lasers. For each shot, temperature measurements were recorded with an infrared thermographic videocamera. The digitized signals were figured as thermal profiles and temperature developments. Ninety-five shots were correctly studied and analyzed: CO2, N = 29; 1.06-μm Nd-YAG, N = 20; 1.32-μm Nd-YAG, N = 46. The histological lesions produced by these three lasers were compared on animals killed 24 hours (N = 20), 8 days (N = 20), and 30 days (N = 5) after the laser impacts. For equivalent densities of energy, the depth of cortical necrosis was comparable for the CO2 laser (200–250 μm) and the 1.32-μm Nd-YAG laser (210–260μm) whatever the date of death; the 1.06-μm Nd-YAG laser shots were responsible for much more important damage (400–550μm). Because of its important absorption in water and nervous tissue, the authors consider the 1.32-μm Nd-YAG laser most suitable for neurosurgery, particularly because it is conducted through optic fibers, and therefore is easy to handle during neurosurgical procedures.  相似文献   
7.
目的 为临床研究肝硬化提供有价值的手段。方法 采用99mTc -RBC测定 93例肝硬化患者肝血流 ,选择峰时 (Tmax) ,半廓清时 (T1/2 )、廓清率 (K值 )、肝血流 (LBF)等作为观察指标 ,与正常对照组比较 ;同时用99mTc-MIBI经直肠给药测定其中 5 4例患者门静脉压力 (PVP) ,以心 /肝 (H/L)比值作为分流指数。结果 肝硬化组Tmax、T1/2 、K及LBF分别为 1.2 6± 0 .99(93)min、5 .75± 3.38(93)min、0 .15 4± 0 .116 (93)及 0 .6 10± 0 .2 89(93)L/min ,除Tmax外 ,与对照组均有非常显著性差异 ;Child -A、B、C级各组之间 (除Tmax外 )也均有非常显著性差异或显著性差异 ;Child -A、B、C级各组H/L分别为 0 .49± 0 .18(2 1)、0 .6 9± 0 .16 (15 )、0 .91± 0 .2 1(18) ;PVP分别为 2 .2 2± 0 .5 7(2 1)kPa、2 .85± 0 .38(15 )kPa及 3.5 4± 0 .6 5 (18)kPa。而对照组的H/L及PVP分别为 0 .30± 0 .12 (16 )及 1.6 1± 0 .38(16 )kPa。Child -A、B、C级各组分别与对照组及各组之间比较 ,除Child -B与C级组PVP无显著性差异 (P >0 .0 5 )外 ,其余均有非常显著性差异 (P <0 .0 1)及显著性差异 (P <0 .0 5 )。结论 本法测定肝血流及门脉压力方便 ,无创伤 ,对分析病情 ,判断疗效 ,指导制订治疗方案 ,估计预后等均有较  相似文献   
8.
目的 :评价99Tcm 核素甲状腺扫描对甲状腺结节的临床诊断价值。方法 :对 2 87例甲状腺结节患者行99Tcm 甲状腺扫描并行甲状腺手术 ,将扫描结果与术后病理诊断进行对比。结果 :扫描对各种甲状腺结节定位诊断准确 ,但各组甲状腺结节扫描定性诊断结果无差异 (P >0 .0 5 )。结论 :发现99Tcm 扫描对甲状腺结节的定位准确 ,但对甲状腺结节良恶性鉴别帮助不大。该方法快捷方便 ,病人所受辐射较少 ,尤其适用于儿童  相似文献   
9.
作者采用沉淀法对药用葡聚糖进行分级纯化,通过家兔实验筛选出合乎淋巴系统定向要求分子量(105000)的葡聚糖,并制成一步标记法的亚锡葡聚糖药盒,4℃贮存8个月,标记率大于95%。~(99)m锝-葡聚糖的体内外稳定性均佳。家兔研究表明:(1)淋巴结内聚集量最高,其他非靶器(除肝脏、肾脏外)均处于极低水平;(2)显像速度快、图像清晰,既显示淋巴结又显示淋巴管;(3)注射部位清除速度快,6.5h清除95%。安全试验表明:~(99)m锝-葡聚糖是一种毒性极低、非常安全的药物。临床试用100余例,均获满意图像,检查全过程1h内完成,检查结果与诊断基本相符,故~(99)m锝-葡聚糖是目前临床上比较理想的淋巴系统显像剂,可进一步推广应用。  相似文献   
10.
In this study we aimed to work out a quantitative prognostic index for preoperative assessment of brain technetium-99m hexamethylpropylene amine oxime (HMPAO) single-photon emission tomography (SPET) in patients referred for urgent carotid endarterectomy due to acute obstructive disease of the internal carotid artery (ICA) and neurological deficit. To this end we compared data from preoperative SPET studies with the postinterventional changes in neurological status in 20 patients (17 males, three females; mean age 53 years, SD 4 years) with acute ischaemic cerebral disorders induced by obstruction of the ICA. Carotid obstruction was diagnosed by ultrasound B-mode study. All patients underwent urgent carotid endarterectomy from the ICA. Patients were divided into two groups in accordance with the results of postoperative follow-up: group A comprised patients with significant (more than 3 points) postoperative improvement in neurological condition as quantified by the Canadian Neurological Scale (11 patients); group B consisted of patients with minimal improvement or deterioration (nine, three of whom died). All patients were studied preoperatively by99mTc-HMPAO SPET. The volume of nonperfused tissue (VS, cm3) was quantified using the Mountz technique. Hypoperfused volume (V hypoperf, cm3) in the affected hemisphere was calculated as the total volume of voxels with99mTc-HMPAO uptake <90% of the contralateral symmetric voxels. Discriminant prognostic function was calculated by discriminant analysis as:PF = 0.072&amp;times;VS + 29.46&amp;times;(VS/V hypoperf). Patients with preoperativePF values <8.20 demonstrated postoperative improvement in neurological status, while the group withPF>8.90 comprised patients who demonstrated minimal improvement or deterioration. PF values in the range 8.20&amp;#x2013;8.90 carried an indefinite prognosis. We conclude that the preoperative99mTc-HMPAO SPET can be used for the selection of patients in whom improvement in neurological status may be expected after urgent surgical correction of acute extracranial obstruction of the ICA.  相似文献   
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