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51.
Background  Cardiac resynchronization therapy (CRT) is approved for the treatment of patients with advanced systolic heart failure and evidence of dyssynchrony on electrocardiograms. However, a significant percentage of patients do not demonstrate improvement with CRT. Echocardiographic techniques have been used for more accurate determination of dyssynchrony. Single photon emission computed tomography (SPECT) myocardial perfusion imaging has not previously been used to evaluate cardiac dyssynchrony. The objective of this study is to evaluate mechanical dyssynchrony as described by phase analysis of gated SPECT images in patients with left ventricular dysfunction, conduction delays, and ventricular paced rhythms. Methods and Results  A novel count-based method is used to extract regional systolic wall thickening amplitude and phase from gated SPECT images. Five indices describing the phase dispersion of the onset of mechanical contraction are determined: peak phase, phase SD, bandwidth, skewness, and kurtosis. These indices were determined in consecutive patients with left ventricular dysfunction (n=120), left bundle branch block (n=33), right bundle branch block (n=19), and ventricular paced rhythms (n=23) and were compared with normal control subjects (n=157). Phase SD, bandwidth, skewness, and kurtosis were significantly different between patients with left ventricular dysfunction, left bundle branch block, right bundle branch block, and ventricular paced rhythms and normal control subjects (all P<.001) Peak phase was significantly different between patients with right ventricular paced rhythms and normal control subjects (P=.001). Conclusions  A novel SPECT technique for describing left ventricular mechanical dyssyn-chrony has been developed and may prove useful in the evaluation of patients for CRT. This study was funded in part by a research grant from the Medtronic-Duke Strategic Alliance, of which Dr Borges-Neto is the primary investigator.  相似文献   
52.
彭晋  吴贵华 《医学影像学杂志》2006,16(8):826-826,833
患者男性,29岁。因体检发现纵隔肿物17天入院。无胸、背痛及胸闷、气促、呼吸困难,无咳嗽、咳痰及咯血。查体:生命体征平稳,双肺呼吸音清晰、未闻及干湿性罗音及胸膜摩擦音。胸透及胸部CT:右后下纵隔类圆形占位,密度较均匀,CT值20~22HU,肿物不随呼吸运动活动。CT诊断:右后下纵隔神经源性良性肿瘤(图1,2)。于全麻下行右后下纵隔肿瘤切除术,病理诊断:(右后下纵隔)支气管源性囊肿。讨论:纵隔支气管囊肿属先天性异常,为前肠囊肿的一种,多见于儿童和青年人。大部分位于气管、支气管周围,多在隆突下和右气管旁。最常见的临床症状是胸痛,无症状…  相似文献   
53.
目的 评估单纯行玻璃体切除术对外因性细菌性眼内炎的疗效。方法 外因性细菌性眼内炎21例(21只眼),其中白内障摘除联合人工晶状体植入术后1只眼,眼球穿通伤后20只眼。均作睫状体平部三切口玻璃体切除术,晶状体混浊者一并切除,若有球内异物一并取出,伴视网膜脱离者,重水或气/液交换复位视网膜后行眼内炎光凝、长效气体或硅油填充以及巩膜环扎,术中灌注液内不加入庆大霉素,术毕不作玻璃体腔注药,术后联合抗生索和激素静脉用药。结果 炎症控制20只眼,术后矫正视力提高20只眼,有效率为80.95%。结论 玻璃体切除术对严重细菌性眼内炎而言是最重要的治疗手段。  相似文献   
54.
The levels and temporal variations of surface ozone at a coastal site in East China during summer and autumn were analyzed and the influences of meteorological parameters on ozone were investigated. An inland city was chosen as a comparison site. The main results and conclusions of this study are: (1) ozone pollution, with a maximum 1 h concentration of 150.98 ppbv, was severe during summer and autumn at the coastal site; (2) the ozone level was obviously higher at the coastal site than that at the inland site in September; (3) besides temperature and solar radiation, sea-land breeze circulation is an important factor influencing the ozone level at the coastal site, and sea breeze often induce high ozone levels (the average ozone concentration for sea breeze was about 13 ppbv higher than that for land breeze).  相似文献   
55.
目的分别构建人乙型肝炎病毒(HBV)X蛋白、羧基端截断的中分子表面蛋白MHBst78、MHBst155编码基因的真核重组表达载体,以便进一步研究其转录激活功能及对宿主细胞信号传导通路的影响。方法设计合成3对寡核苷酸引物,以adr亚型HBV质粒pHBVDNA为模板,采用PCR法分别扩增HBVX基因、MHBst78与MHBst155编码基因片段;用HindⅢ,KpnⅠ双酶切HBVⅩ基因;用HindⅢ和BamHⅠ双酶切MHBst78与MHBst155编码基因片段后,分别定向插入到真核表达载体pcDNA3.1相应酶切位点,转化宿主菌JM109,提取质粒,分别用上述内切酶酶切及DNA测序鉴定重组质粒。结果酶切重组体显示所切下的片段大小均与预计相符,测序结果与文献报道序列及预计结果一致。结论成功构建了HBVX基因、羧基端截断的HBV中分子表面蛋白MHBst78、MHBst155编码基因的真核重组表达载体,为进一步研究HBV转录激活蛋白HBx、MHBst78MHBst155对宿主细胞信号转导通路的影响奠定基础。  相似文献   
56.
Object A radiation dose of 40–50 Gy is able to produce a cure rate of more than 90% in intracranial pure germinoma. However, many attempts have been made to reduce the dose and volume of radiation without compromising the disease control rate because of the toxicity of irradiation. This retrospective study is intended to provide the physician with an appropriate therapeutic strategy. Materials and methods We reviewed a series of 10 recurrent germinomas among 117 germinomas diagnosed histologically or clinically between 1979 and 2002. These patients involved underwent three different treatment modalities; radiation alone (N = 71), chemotherapy alone (N = 9), and combined therapy (N = 37). The 10-year overall and relapse-free survival rates were 97 and 93% in the radiation alone group, 89 and 67% in the chemotherapy alone group, and 92 and 92% in the combined therapy group, respectively. As expected, both radiation therapy and combined therapy were effective in controlling the disease. Tumor recurrence was closely related to the volume of radiation but not to the dose of radiation. If the tumor bed and craniospinal axis were fully covered, the radiation dose might be reduced. Chemotherapy alone showed earlier recurrence and a higher tumor recurrence rate. In the case of combined therapy, chemotherapy was useful in reducing the radiation dose but revealed some toxicity (death of two patients). Conclusions The investigation of a possible further dose reduction seems worthwhile. Radiation therapy alone with a dose of less than 40 Gy should be compared with ongoing chemotherapeutic protocols combined with low-dose irradiation.  相似文献   
57.
肾上腺区神经节细胞瘤(附18例报告)   总被引:3,自引:0,他引:3  
目的较全面的了解神经节细胞瘤的临床特点及治疗方法。方法回顾性分析18例病理确诊的神经节细胞瘤患者临床表现、实验室检查、影像学检查和治疗效果。结果15例是无临床症状的影像学偶然发现病例,内分泌检查均在正常范围;另外3例以阵发性高血压为主要临床表现,其中1例尿儿茶酚胺升高,肾上腺髄质显像(MIBG)阳性。18例B型超声检查均为低回声;13例CT平扫见散在点状高密度影,12例CT增强扫描肿瘤周边强化明显。手术前诊断为嗜铬细胞瘤12例,神经节细胞瘤4例,肾上腺无功能腺瘤2例。18例行肿瘤切除,随访6个月~7年,高血压症状消失,2例肿瘤复发。结论肾上腺区神经节细胞瘤与肾上腺髄质肿瘤难以鉴别,综合各项影像学检查对诊断有较高的参考价值。手术治疗是唯一的有效方法。  相似文献   
58.
目的:探讨急诊外伤性胃肠穿孔的CT征象及诊断价值。方法:收集18例经手术证实的外伤性胃肠道穿孔的临床资料及CT征象,分析与总结胃肠道破裂穿孔CT扫描的各种有价值的表现。结果:18例外伤急诊患者中,胃、十二指肠、空回肠与结肠穿孔各1,2,12,3例,其中空回肠为多处破裂,CT主要征象为腹腔散在积液征、游离气腹征、肠系膜与肠壁增厚模糊征、造影剂外溢征。结论:CT扫描在外伤性胃肠道穿孔急诊患者的检查中有定性诊断价值,综合分析各种征象,会明显提高CT的诊断正确率。  相似文献   
59.
目的:探讨和研究治疗晚期面瘫的手术治疗,总结应用以足底内侧动静脉为蒂的(足母)展肌游离移植一期修复晚期面瘫40例效果和经验.方法:选取(足母)展肌为供肌,以足底内侧动静脉及其延续的胫后动静脉为血管蒂,以支配(足母)展肌神经及其延续的足底内侧神经和胫神经为神经蒂.(足母)展肌移植于患侧面部皮下,肌近断固定于口角,远端固定于耳前颧弓,血管神经蒂通过上唇皮下隧道与健侧面动静脉和面神经颊支吻合.结果:经随访一年以上,23例恢复了面部静态对称和理想的下面部随意和不随意运动;8例恢复了面部静态对称和部分下面部随意和不随意运动;9例仅恢复了面部静态对称.结论:(足母)展肌游离移植一期修复晚期面瘫具有疗效好、手术操作简便、肌肉大小适中、血管神经蒂走行位置恒定紧密伴行、血管神经蒂可切取较长、变跨面神经移植和肌肉移植的两期移植为一期移植等优点;而且,神经是血管化移植.  相似文献   
60.
Pituitary abscess is a rare and potentially lethal condition. Pituitary abscess in a pregnant woman has not been previously described. A 38-year-old pregnant woman (34 weeks gestation) with a pituitary mass complained of a progressive headache and sudden visual impairment. She was afebrile and had no inflammatory symptoms on admission. On MRI, the preoperative diagnosis was pituitary adenoma with sphenoid sinusitis. She underwent an uncomplicated transsphenoidal procedure for removal of the pituitary mass. The next day, labor commenced and a healthy preterm baby was delivered. Pathologic examination of the intrasellar mass showed polymorphonuclear cells, debris and no tumor cells. The sellar contents were cultured and Streptococcus viridans was grown. To our knowledge this is the first case of pituitary abscess reported during pregnancy. Although the patient was pregnant, the transsphenoidal approach was safe for the mother and the fetus. Surgical drainage and antibiotic therapy are required for the definitive treatment of this condition.  相似文献   
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