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71.
Conventional work-up (CWU) with chest radiography, abdominal ultrasonography, and skeletal scintigraphy has limited value in M staging of nonkeratinizing nasopharyngeal carcinoma (NPC). Our aim was to evaluate whether (18)F-FDG PET could replace CWU by comparing their diagnostic efficacies. METHODS: Patients with histologically proven nonkeratinizing NPC and no prior treatment were prospectively enrolled. All study participants underwent CWU and (18)F-FDG PET for primary M staging. Distant metastasis was considered to be present if there was any reliable evidence identified within 1 y after diagnosis. The comparative diagnostic efficacies of (18)F-FDG PET, CWU, and the combination of (18)F-FDG PET and CWU (PET+CWU) were evaluated using the areas under the receiver-operating-characteristic (ROC) curves. RESULTS: Sixty-one (20.3%) of 300 eligible patients were found to have distant metastases. On a patient-based analysis, (18)F-FDG PET was found to be more effective than CWU (P < 0.001), whereas it was equally effective with PET+CWU (P = 0.130). On region-based analyses, (18)F-FDG PET was more effective than skeletal scintigraphy and chest radiography for detecting bone metastases (P < 0.001) and chest metastases (P < 0.001), respectively. (18)F-FDG PET and abdominal ultrasound were equally effective for detecting hepatic metastases (P = 0.127). On region-based analyses, the combination of (18)F-FDG PET and CWU did not yield any noticeable increase in diagnostic efficacy. CONCLUSION: (18)F-FDG PET can replace CWU in primary M staging of nonkeratinizing NPC.  相似文献   
72.
UVA1作用于皮肤成纤维细胞,使其凋亡增加、酶活性及细胞因子的分泌改变,造成真皮层损伤,还可促进伤口愈合,被用于治疗某些与皮肤成纤维细胞增生相关的皮肤病,如硬皮病、瘢痕疙瘩及增生性瘢痕等。本文就UVA1对皮肤成纤维细胞的影响及其在皮肤病治疗中的应用作以综述。  相似文献   
73.
Two organ recipients developed serologic evidence of syphilis infection after renal transplantation from a common deceased donor with a history of treated syphilis. Testing of donor serum for syphilis, which occurred after transplantation, gave results interpreted as consistent with past infection. However, subsequent serologic results in the recipients suggested transmission of infection at transplantation due to active infection of the donor. This may be explained by recent donor re-infection in view of the current syphilis epidemic in the United Kingdom. An initial error in the treatment of recipients further served to highlight unfamiliarity in managing this resurgent infection in the context of organ transplantation.  相似文献   
74.
自由基损伤和β2糖蛋白1在自身免疫疾病中的作用   总被引:2,自引:0,他引:2  
目的 研究被自由基氧化修饰的β2糖蛋白1(β2GPl)在自身免疫疾病中自身抗体产生中的作用。方法 采用高氯酸沉淀,两步肝素连接的交联琼脂糖凝胶层析结合葡聚糖凝胶G—100分离纯化大鼠β2GP1;应用自由基氧化修饰大鼠β2GP1;氧化修饰的β2GP1(oxβ2GPl)、β2GPl分别加与不加心磷脂(CL)及CL免疫大鼠,ELISA方法检测免疫大鼠血清中抗β2GP1抗体和抗心磷脂抗体(ACA)。结果 两步亲和层析结合凝胶过滤层析有效地分离纯化了大鼠β2GPl,蛋白纯度达90.78%;通过碳基含量测定证实了自由基对β2GP1的氧化修饰;oxβ2GGP1加CL、β2GP1加CL、oxβ2GPl免疫组与空白对照组、实验对照组比较ACA水平有显著升高(P<0.001),oxβ2GP1加CL免疫组与β2GPl加CL免疫组比较ACA水平差异有显著性(P<0.05);oxβ2GP1免疫组与oxβ2GPl加CL免疫组比较ACA水平差异不显著(P>0.05);oxβ2GPl加CL、oxβ2GPl免疫组与对照组比较,抗oxβ2GP1抗体水平有显著升高(P<0.05)。结论 两步肝素连接的交联琼脂糖凝胶层析结合葡聚糖凝胶G—100能有效地分离纯化β2GPl;oxβ2GPl诱导了ACA和抗oxβ2GPl抗体的产生;β2GPl可能是自身免疫疾病发生过程重要的辅助因子或靶抗原,而自由基对β2GP1损伤可能是自身免疫疾病发病机制中的一个重要病理过程。  相似文献   
75.
INTRODUCTION: Elderly patients who suffer trauma have a higher mortality and use disproportionately more trauma resources than younger patients. To compare these 2 groups and determine the outcomes and characteristics of elderly patients, we reviewed patients in these 2 groups admitted and treated in our tertiary care provincial trauma centre. METHODS: From the provincial trauma registry we selected a cohort of 40 geriatric patients (group 1) (> or = 65 yr of age) with an ISS of 16 or more who were admitted to and spent time in our trauma service for more than 48 hours and compared them with a similar randomly selected cohort of 44 patients (group 2) aged 20-30 years. Family physicians were contacted for follow-up of these patients 2 years after discharge. We considered length of hospital stay, complications, disposition of the patients and use of consultation services. RESULTS: Patients in group 1 had a mean age of 72.1 years (range from 65-98 yr) and a mean ISS of 27.3 (range from 17-50). Patients in group 2 had a mean age of 26.3 years (range from 22-29 yr) and a mean ISS of 26.3 (range from 17-54). Hospital stay was significantly longer in the group 1: 34.5 days (95% confidence interval [CI]: 24-44 d) versus 21.6 days (95% CI: 15-28 d). More elderly patients experienced complications (35 v. 13, p < 0.001) and required medical consultations (35 v. 26, p < 0.001). In-hospital death rates were 8% (3 of 40) and 4% (2 of 44) respectively (p = 0.3). Fewer geriatric patients could be discharged home (35% [14 of 40] v. 27% [22 of 44], p = 0.056) or to rehabilitation facilities (28% [11 of 40] v. 34% [15 of 44], p = 0.3). Five geriatric patients were discharged to nursing homes (p = 0.007). Of the geriatric patients discharged to rehabilitation facilities or home, 75% were independent 2 years after discharge. CONCLUSIONS: Aggressive care for geriatric trauma patients is warranted, and resources should be directed toward rehabilitation. Based on our findings, we expect that creating a directed care pathway for these patients, targetting complications and earlier discharge, will further improve their outcomes.  相似文献   
76.
目的 从基因水平探讨霍奇金淋巴瘤(HL)组织中H/RS细胞(Hodgkin and Reed-Sternberg cells)是否起源于B细胞、H/RS细胞的克隆性以及与背景淋巴细胞的相互关系。方法 对33例经典霍奇金淋巴瘤(cHL)石蜡刮片组织进行IgH基因重排分析,并对其中6例重排阳性的病例经B细胞特异性激活蛋白(BSAP)免疫标记,将标记阳性的H/RS细胞和背景淋巴细胞进行微切割后进一步行IgH基因重排分析。结果 16例石蜡刮片组织IgH基因重排阳性。对6例经BSAP标记的cHL成功进行了微切割,其中19管H/RS细胞中,有14管出现重排阳性,细胞数目不同的各管阳性率无显著性差异(P=0.290);12管背景淋巴细胞有2管出现重排阳性,H/RS细胞与背景淋巴细胞的阳性率有显著性差异(P=0.002)。结论 支持H/RS细胞来源于B细胞的理论,认为部分背景淋巴细胞可能具有瘤性增生活性,参与H/RS细胞的前体细胞组成。  相似文献   
77.
Aim: The prognosis of patients with disseminated colorectal carcinoma is poor except for those with single organ pulmonary or hepatic metastases. The objective of the present study was to evaluate the result of pulmonary metastasectomy for colorectal secondary and to identify the prognostic factors. Methods: This was a retrospective study of 80 patients who had pulmonary metastasectomy for pulmonary secondary from colorectal carcinoma in Queen Elizabeth Hospital, Hong Kong. Results: The overall 5‐year and 10‐year survival rates of the entire cohort were 42.5% and 35.5%, respectively. High premetastasectomy carcinoembryonic antigen (> 20 μg/dL), short disease‐free interval (< 12 months) and incomplete resection were the independent prognostic factors. Neither the characteristics of the primary colorectal tumour nor the number of metastatic nodules had a significant contribution to the long‐term survival. Six patients underwent second pulmonary metastasectomy and three were still free from tumour recurrence after the second operation. Conclusion: Patients with pulmonary metastases from colorectal carcinoma would benefit from pulmonary metastasectomy. High premetastasectomy carcinoembryonic antigen and short disease‐free interval were negative predictive factors for survival. Long‐term follow‐up study is required, as recurrence can occur more than 5 years after pulmonary metastasectomy. Also, whether the survival benefit is due to surgical treatment effect or lead‐time bias remains undecided.  相似文献   
78.
MUC-1基因在胃癌和外周血中的表达及临床意义   总被引:1,自引:0,他引:1  
目的:检测胃癌MUC-1的表达情况及其与临床分期和转移的相关性。方法:应用逆转录聚合酶链反应(RT-PCR)和免疫组化方法检测胃癌活检标本和外周血中MUC-1基因和蛋白的表达水平。结果:在56例胃癌病例中MUC-1 mRNA阳性表达率为48.2%,MUC-1蛋白阳性表达率为53.6%,临床分期中I和II期病人阳性表达率MUC-1 RNA为33.3%,MUC-1蛋白为40%,而-Ⅲ期病人则分别高达65.4%和69.2%,二者差异有显著性意义(P<0.05),在淋巴结转移的患者中外周血的癌细胞MUC-1高表达,阳性率为73%,结论:MUC-1是一种较好反映胃癌恶性程度和转移性的肿瘤标志物。  相似文献   
79.
脑卒中患者吞咽障碍及康复效果影像学研究   总被引:14,自引:1,他引:13  
目的探讨电视X线透视吞咽功能检查(videofluoroscopic swallowing study,VFSS)在脑卒中患者吞咽功能评估中的应用价值,观察脑卒中后吞咽障碍发生情况,康复前后患者吞咽功能变化.方法脑卒中患者70例及健康成人80名分别作为研究组与对照组均进行VFSS,比较两组误吸等VFSS异常征象的发生情况.对发现误吸患者进行吞咽功能康复训练4周,训练后复查VFSS,比较训练前后吞咽异常的发生情况变化.结果对照组渗透或误吸、口腔滞留、咽腔滞留的发生率为5.0%,13.4%,25.3%.主要为轻度渗透及口咽腔滞留.研究组渗透或误吸、口腔滞留、咽腔滞留发生率为45.0%,46.5%,48.9%,主要为重度渗透或误吸,中重度口咽腔滞留.其中隐匿性误吸为10次(占总误吸的24.4%).误吸患者康复治疗后渗透或误吸发生率较康复治疗前减少(P<0.05).结论脑卒中后吞咽障碍在康复期仍较为常见,可表现为多种影像学异常.VFSS可确切诊断吞咽异常,进行针对性康复训练,使患者吞咽功能提高.  相似文献   
80.
A 1,934-bp muscle-specific promoter from the zebrafish mylz2 gene was isolated and characterized by transgenic analysis. By using a series of 5' promoter deletions linked to the green fluorescent protein (gfp) reporter gene, transient transgenic analysis indicated that the strength of promoter activity appeared to correlate to the number of muscle cis-elements in the promoter and that a minimal -77-bp region was sufficient for a relatively strong promoter activity in muscle cells. Stable transgenic lines were obtained from several mylz2-gfp constructs. GFP expression in the 1,934-bp promoter transgenic lines mimicked well the expression pattern of endogenous mylz2 mRNA in both somitic muscle and nonsomitic muscles, including fin, eye, jaw, and gill muscles. An identical pattern of GFP expression, although at a much lower level, was observed from a transgenic line with a shorter 871-bp promoter. Our observation indicates that there is no distinct cis-element for activation of mylz2 in different skeletal muscles. Furthermore, RNA encoding a dominant negative form of cAMP-dependent protein kinase A was injected into mylz2-gfp transgenic embryos and GFP expression was significantly reduced due to an expanded slow muscle development at the expense of GFP-expressing fast muscle. The mylz2-gfp transgene was also transferred into two zebrafish mutants, spadetail and chordino, and several novel phenotypes in muscle development in these mutants were discovered.  相似文献   
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