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91.
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目的了解河北省儿童医院住院患儿EB病毒(EBV)感染的流行病学特征,为儿童EBV感染的诊断和预防提供科学依据。方法收集2017年1—12月河北省儿童医院0~14岁EBV感染住院患儿的全血样本,采用酶联免疫吸附试验(ELISA)检测其EBV衣壳抗原(VCA)IgG及IgM抗体,抗早期抗原(EA)IgG抗体和抗核抗原1(NA1)IgG抗体,以检测结果为研究样本的抗体谱。根据4种EBV抗体的检测结果分为现症感染(抗VCA-IgM抗体阳性,抗NA1-IgG抗体阴性、抗VCA-IgG抗体、抗EA-IgG抗体阳性或阴性)、亚急性感染(抗VCA-IgG抗体阳性,抗VCA-IgM抗体、抗NA1-IgG抗体、抗EA-IgG抗体阳性或阴性)、既往感染(抗NA1-IgG抗体阳性,抗VCA-IgG抗体阳性或阴性,其他抗体均为阴性)和未感染(4种抗体均阴性)。按照患儿年龄、检出月份和性别分析各组的阳性率。结果共纳入符合要求的样本4 451例,其中3 257例(73.17%)抗体谱提示EBV感染,包括现症感染380例(8.54%)、亚急性感染616例(13.84%)、既往感染2 261例(50.80%)。不同年龄组原发阳性检出率差异有统计学意义(P<0.05),其中学龄前(>3岁)组的阳性检出率最高(P<0.05);不同检出月份组阳性检出率差异有统计学意义(P<0.05),7月份阳性检出率高于其他月份(P<0.05);男性患儿与女性患儿EBV感染率差异无统计学意义(P>0.05)。380例现症感染患儿的疾病谱以血液系统疾病[传染性单核细胞增多症、急性粒细胞缺乏症、血小板减少性紫癜、EBV相关嗜血细胞综合征]为主,其中传染性单核细胞增多症为临床常见疾病;其次是呼吸系统疾病(急性支气管炎、疱疹性咽峡炎、急性扁桃体炎);其他疾病谱包括神经系统疾病及血流感染、肾病综合征、川崎病。结论河北省儿童医院住院患儿EBV阳性检出率有年龄和检出月份差异,现症感染以血液系统疾病患儿为主,医院应根据流学病学特征制定相应预防措施。  相似文献   
93.
Familial Cancer - Multigene panel tests for hereditary cancer syndromes are increasingly utilized in the care of colorectal cancer (CRC) and polyposis patients. However, widespread availability of...  相似文献   
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95.
Successful multidrug-resistant clones are increasing in prevalence globally, which makes the ability to identify these clones urgent. However, adequate, easy-to-perform, and reproducible typing methods are lacking. We investigated whether DiversiLab (DL), an automated repetitive-sequence-based PCR bacterial typing system (bioMérieux), is suitable for comparing isolates analyzed at different geographic centers. A total of 39 Escherichia coli and 39 Klebsiella species isolates previously typed by the coordinating center were analyzed. Pulsed-field gel electrophoresis (PFGE) confirmed the presence of one cluster of 6 isolates, three clusters of 3 isolates, and three clusters of 2 isolates for each set of isolates. DL analysis was performed in 11 centers in six different countries using the same protocol. The DL profiles of 425 E. coli and 422 Klebsiella spp. were obtained. The DL system showed a lower discriminatory power for E. coli than did PFGE. The local DL data showed a low concordance, as indicated by the adjusted Rand and Wallace coefficients (0.132 to 0.740 and 0.070 to 1.0 [E. coli] and 0.091 to 0.864 and 0.056 to 1.0 [Klebsiella spp.], respectively). The central analysis showed a significantly improved concordance (0.473 to 1.0 and 0.290 to 1.0 [E. coli] and 0.513 to 0.965 and 0.425 to 1.0 [Klebsiella spp.], respectively). The misclassifications of profiles for individual isolates were mainly due to inconsistent amplification, which was most likely due to variations in the quality and amounts of the isolated DNA used for amplification. Despite local variations, the DL system has the potential to indicate the occurrence of clonal outbreaks in an international setting, provided there is strict adherence to standardized, reproducible DNA isolation methods and analysis protocols, all supported by a central database for profile comparisons.  相似文献   
96.
OBJECTIVE: To examine the association between abnormal exercise electrocardiographic (E-ECG) test results and mortality (all-cause and that resulting from coronary heart disease [CHD] or cardiovascular disease [CVD]) in a large population of asymptomatic men with metabolic syndrome (MetS).PATIENTS AND METHODS: A total of 9191 men (mean age, 46.9 years) met the criteria of having MetS. All completed a maximal E-ECG treadmill test (May 14, 1979, through April 9, 2001) and were without a previous CVD event or diabetes at baseline. Main outcomes were all-cause mortality, mortality due to CHD, and mortality due to CVD. Cox regression analysis was used to quantify the mortality risk according to E-ECG responses.RESULTS: During a follow-up of 14 years, 633 deaths (242 CVD and 150 CHD) were identified. Mortality rates and hazard ratios (HRs) across E-ECG responses were the following: for all-cause mortality: HR, 1.36; 95% confidence interval (CI), 1.09-1.70 for equivocal responses and HR, 1.41; 95% CI, 1.12-1.77 for abnormal responses (Ptrend<.001); for mortality due to CVD: HR, 1.29; 95% CI, 0.88-1.88 for equivocal responses and HR, 2.04; 95% CI, 1.46-2.84 for abnormal responses (Ptrend<.001); and for mortality due to CHD: HR, 1.62; 95% CI, 1.02-2.56 for equivocal responses and HR, 2.45; 95% CI, 1.62-3.69 for abnormal responses (Ptrend<.001). A positive gradient for CHD, CVD, and all-cause mortality rates across E-ECG categories within 3, 4, or 5 MetS components was observed (P<.001 for all).CONCLUSION: Among men with MetS, an abnormal E-ECG response was associated with higher risk of all-cause, CVD, and CHD mortality. These findings underscore the importance of E-ECG tests to identify men with MetS who are at risk of dying.ACLS = Aerobics Center Longitudinal Study; CHD = coronary heart disease; CI = confidence interval; CRF = cardiorespiratory fitness; CVD = cardiovascular disease; DM = diabetes mellitus; ECG = electrocardiography; E-ECG = exercise ECG; HR = hazard ratio; MET = metabolic equivalent; MetS = metabolic syndrome; NDI = National Death Index; SRI = stress-recovery indexMetabolic syndrome (MetS) is a clustering of cardiovascular disease (CVD) risk factors,1 including abdominal obesity, atherogenic dyslipidemia, elevated blood pressure, and insulin resistance,2 that currently affects nearly 25% of Americans and is a growing concern because of increasing rates of obesity and hypertension.3 Because many of the components of MetS are associated with an increased risk of CVD and death, a noninvasive diagnosis of subclinical CVD in patients with MetS is important and may optimize secondary preventive interventions in this high-risk population.We showed earlier that abnormal exercise electrocardiographic (E-ECG) results during maximal exercise testing was associated with an elevated risk of incident coronary heart disease (CHD), CVD, and all-cause mortality in 2854 men with diabetes mellitus (DM).4 Thus, although DM is considered a CHD risk equivalent, important additional information for risk stratification can be obtained from exercise testing. We also showed that exercise testing can be used to identify women with impaired fasting glucose, a predecessor to DM and MetS, who are at high risk of all-cause mortality.5 Callaham et al6 studied 1747 US veterans with DM and showed that exercise-induced ST-segment depression was associated with more CVD events during a mean follow-up of 2 years than was observed in participants without ST-segment depression. In a study of 45 patients with exercise-induced silent ischemia, Weiner et al7 reported that patients with DM had worse outcomes in terms of CVD events than persons without DM.Currently, no known studies have evaluated the association between abnormal E-ECG responses and all-cause, CHD, and CVD mortality risk in men with MetS. Although sparse, some studies have examined the association between E-ECG responses and CHD risk in men with components of MetS. Ekelund et al8 reported that positive findings on E-ECG was an independent predictor of CVD events in men with hypercholesterolemia. Laukkanen et al9 reported that exercise-induced ischemia was associated with a higher risk of adverse outcomes in persons at high risk of CHD. Bigi et al10 suggested that the stress-recovery index (SRI) predicts all-cause mortality in persons with hypertension.Therefore, our study primarily aimed to evaluate the association between abnormal E-ECG test results and mortality (all-cause and that due to CHD or CVD) in a large population of asymptomatic men with MetS. We showed earlier that a maximal E-ECG test performed in asymptomatic men free of CVD can predict future risk of CHD death,11 and that an abnormal test result was a more powerful predictor of risk in those with DM than those without the diagnosis.4 The current study will expand this earlier report and focus on men with MetS.  相似文献   
97.

Purpose

The purpose of this trial was to evaluate an immunoassay for urinary nuclear matrix protein, NMP22,* as an indicator for transitional cell carcinoma of the urinary tract.

Materials and Methods

Three groups of subjects participated in this trial of NMP22: 1--175 with transitional cell carcinoma, 2--117 with benign urinary tract conditions and 3--375 healthy volunteers. Each subject provided a single (3 voids) urine sample for analysis at the time of study entry. Each sample was assayed for the level of NMP22.

Results

In normal healthy volunteers and in subjects with benign conditions median NMP22 levels were 2.9 and 3.3 units per ml., respectively. Median urinary NMP22 levels in patients with transitional cell carcinoma were significantly greater than in comparison subjects. Patients with active transitional cell carcinoma had significantly greater median urinary NMP22 levels than those with no evidence of disease (6.04 versus 4.11 units per ml., p = 0.027, 1-tailed Mann-Whitney U test). We noted no effect of tumor grade, extent of disease or exposure to intravesical therapy on urinary NMP22 levels.

Conclusions

NMP22 is a promising urinary tumor marker for monitoring transitional cell carcinoma. Nuclear matrix proteins are a new class of tumor markers that represent the basis for the development of assays with increased efficacy for the detection and treatment of cancer.  相似文献   
98.
流式细胞分析技术(flow cytometry,FCM),又称流式细胞术,是一种在功能水平上对单细胞或其他生物粒子进行定量分析和分选的技术,具有广泛的科研应用价值.采用理论与实践并举,结合讨论的教学方式,在教师队伍开设针对性的培训课程,对深刻理解并在科研工作中有效利用该技术具有及其重要意义.同时以教学促科研,以科研促技...  相似文献   
99.
Endometrial carcinoma (EC) molecular classification based on four molecular subclasses identified in The Cancer Genome Atlas (TCGA) has gained relevance in recent years due to its prognostic utility and potential to predict benefit from adjuvant treatment. While most ECs can be classified based on a single classifier (POLE exonuclease domain mutations – POLEmut, MMR deficiency – MMRd, p53 abnormal – p53abn), a small but clinically relevant group of tumours harbour more than one molecular classifying feature and are referred to as ‘multiple-classifier’ ECs. We aimed to describe the clinicopathological and molecular features of multiple-classifier ECs with abnormal p53 (p53abn). Within a cohort of 3518 molecularly profiled ECs, 107 (3%) tumours displayed p53abn in addition to another classifier(s), including 64 with MMRd (MMRd–p53abn), 31 with POLEmut (POLEmut–p53abn), and 12 with all three aberrations (MMRd–POLEmut–p53abn). MMRd–p53abn ECs and POLEmut–p53abn ECs were mostly grade 3 endometrioid ECs, early stage, and frequently showed morphological features characteristic of MMRd or POLEmut ECs. 18/28 (60%) MMRd–p53abn ECs and 7/15 (46.7%) POLEmut–p53abn ECs showed subclonal p53 overexpression, suggesting that TP53 mutation was a secondary event acquired during tumour progression. Hierarchical clustering of TCGA ECs by single nucleotide variant (SNV) type and somatic copy number alterations (SCNAs) revealed that MMRd–p53abn tumours mostly clustered with single-classifier MMRd tumours (20/23) rather than single-classifier p53abn tumours (3/23), while POLEmut–p53abn tumours mostly clustered with single-classifier POLEmut tumours (12/13) and seldom with single-classifier p53abn tumours (1/13) (both p ≤ 0.001, chi-squared test). Finally, the clinical outcome of patients with MMRd–p53abn and POLEmut–p53abn ECs [stage I 5-year recurrence-free survival (RFS) of 92.2% and 94.1%, respectively] was significantly different from single-classifier p53abn EC (stage I RFS 70.8%, p = 0.024 and p = 0.050, respectively). Our results support the classification of MMRd–p53abn EC as MMRd and POLEmut–p53abn EC as POLEmut. © 2019 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.  相似文献   
100.
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