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101.
用中国药品生物制品检定所检定合格的国内外HBsAgEIA试剂及ABBOTT抗 HBs、抗 HBcEIA试剂 ,对所收集的 13份HBsAg疑难判定血清进行检测 ,并用PCR方法检测血清中HBVDNA ,结果显示国内外HBsAg试剂对部分HBVDNA阳性样品的检出率差异较大 ,提示这些样品可能为S基因突变株或HBsAg含量较低 ,因此 ,HBsAgEIA试剂的敏感度仍有待进一步提高 ,并应进一步研制检测S基因突变株的HBsAg诊断试剂。  相似文献   
102.
Abstract

Background

It has been demonstrated that oxidative stress can induce red blood cell rigidity and haemolysis, which in turn can cause hyperviscosity and hyperbilirubinaemia, respectively. However, haemolysis may be associated with a low level of haemoglobin, which reduces whole blood viscosity (WBV). Bilirubin can behave as antioxidant or oxidant, and one uncharted course for diagnostic pathology is how or whether bilirubinaemia and viscosity are associated. Further, oxidative stress is now being assessed using lipoprotein-a (Lp(a)), among other things but whether it is associated with blood viscosity has not been established.

Aim

This study investigates the association and correlation of haemoglobin level and WBV with serum Lp(a) and bilirubin levels in a general population of patients.

Materials and methods

Sixty-eight cases that were tested for Lp(a), concomitantly with full blood count and liver function, in our archived clinical pathology database were used in this study. WBV levels were determined using a validated formula. Multivariate and univariate analyses as well as correlation were performed.

Results

WBV was found to be significantly associated with bilirubin (P < 0.02), but not with Lp(a). Haemoglobin concentration was inversely correlated with Lp(a) (P < 0.04), but not with bilirubinaemia.

Conclusion

This pilot study suggests that hyperbilirubinaemia and hyperviscosity are associated and positively correlated. Consideration of whether serum bilirubin (as an indirect index of oxidative stress) can be used in combination with WBV (as index of macrovascular effect of oxidative stress) to assess oxidative damage is recommended.  相似文献   
103.
104.
ObjectiveTo investigate, as a discovery phase, if 3D knee kinematics assessment parameters can serve as mechanical biomarkers, more specifically as diagnostic biomarker and burden of disease biomarkers, as defined in the Burden of Disease, Investigative, Prognostic, Efficacy of Intervention and Diagnostic classification scheme for osteoarthritis (OA) (Altman et al., 1986). These biomarkers consist of a set of biomechanical parameters discerned from 3D knee kinematic patterns, namely, flexion/extension, abduction/adduction, and tibial internal/external rotation measurements, during gait recording.Methods100 medial compartment knee OA patients and 40 asymptomatic control subjects participated in this study. OA patients were categorized according to disease severity, by the Kellgren and Lawrence grading system. The proposed biomarkers were identified by incremental parameter selection in a regression tree of cross-sectional data. Biomarker effectiveness was evaluated by receiver operating characteristic curve analysis, namely, the area under the curve (AUC), sensitivity and specificity.ResultsDiagnostic biomarkers were defined by a set of 3 abduction/adduction kinematics parameters. The performance of these biomarkers reached 85% for the AUC, 80% for sensitivity and 90% for specificity; the likelihood ratio was 8%. Burden of disease biomarkers were defined by a 3-decision tree, with sets of kinematics parameters selected from all 3 movement planes.ConclusionThe results demonstrate, as part of a discovery phase, that sets of 3D knee kinematic parameters have the potential to serve as diagnostic and burden of disease biomarkers of medial compartment knee OA.  相似文献   
105.
A novel coronavirus, designated as SARS-CoV-2, first emerged in Wuhan City, Hubei Province, China, in late December 2019. The rapidly increasing number of cases has caused worldwide panic. In this review, we describe some currently applied diagnostic approaches, as well as therapeutics and vaccines, to prevent, treat and control further outbreaks of SARS-CoV-2 infection.  相似文献   
106.
目的:评价脑脊液检查在早产儿及足月儿细菌性脑膜炎诊断中的价值。方法:选取2014年6月1日至2016年12月31日上海市儿童医院新生儿科收治的行腰椎穿刺检查的447例新生儿,回顾性分析新生儿的一般资料、脑脊液常规生化、培养等指标,根据胎龄将患儿分为早产儿167例与足月儿280例,再根据有无患发细菌性脑膜炎分为早产儿细菌性脑膜炎27例(早产儿观察组)、早产儿非细菌性脑膜炎140例(早产儿对照组)、足月儿细菌性脑膜炎38例(足月儿观察组)、足月儿非细菌性脑膜炎242例(足月儿对照组),采用受试者工作特征(ROC)曲线评估蛋白定量、白细胞计数、葡萄糖对早产儿及足月儿细菌性脑膜炎的诊断价值。结果:与同组对照组相比,足月儿观察组和早产儿观察组蛋白定量和白细胞计数均明显升高,而葡萄糖含量显著下降,且差异均具有统计学意义(P0.05);本研究65例细菌性脑膜炎患儿脑脊液培养分离出11株细菌(16.9%)。足月儿脑脊液白细胞计数、蛋白定量以及葡萄糖诊断细菌性脑膜炎的ROC曲线下面积分别为0.995、0.846、0.703。早产儿脑脊液白细胞计数、蛋白定量以及葡萄糖诊断细菌性脑膜炎ROC曲线下面积分别为0.970、0.711、0.705。结论:脑脊液白细胞计数、蛋白定量在足月儿和早产儿细菌性脑膜炎中具有较高的诊断价值。  相似文献   
107.
目的:探讨超声心动图检查对慢性肺源性心脏病患者右心功能的诊断价值。方法:选取2016年8月至2017年12月间本院收治的35例慢性肺源性心脏病患者作为实验组,并选择同期健康体检者35例作为对照组,全部受试者均给予超声心动图检查。分别比较两组右房横径(RA)、右室前后径(RV)、肺动脉平均压(MPAP)、射血分数(EF)、舒张晚期A波峰值流速与舒张早期E波峰值流速的比值(A/E)和右心室Tei指数。同时比较实验组采用常规12导联心电图检查及超声心动图检查的诊断阳性率、右心扩大阳性率和右心扩大伴心衰阳性率。结果:与对照组相比,实验组RA、RV以及MPAP均升高,组间比较差异有统计学意义(P0.05)。与对照组相比,实验组EF明显降低,而A/E值、Tei指数明显升高,组间比较差异有统计学意义(P0.05)。实验组超声心动图检查的诊断阳性率、右心扩大阳性率和右心扩大伴心衰阳性率均高于常规12导联心电图检查(P0.05)。结论:应用超声心动图检查能够有效诊断慢性肺源性心脏病患者的右心功能,而且操作简单方便,诊断阳性率较高。  相似文献   
108.
目的:探讨扩散张量成像(DTI)定量参数对脑胶质瘤的诊断价值及其与血管内皮生长因子(VEGF)、细胞核增殖相关抗原(Ki-67)的关系。方法:选取2014年6月到2017年6月期间在我院接受治疗的90例脑胶质瘤患者,根据病理分级的不同分为中低级别组(n=46)和高级别组(n=44),比较两组患者表观扩散系数(ADC)值、各向异性分数(FA)值、相对表观扩散系数(rADC)值、相对各向异性分数(rFA)值、VEGF和Ki-67的阳性率,分析ADC值、FA值、rADC值、rFA值与VEGF、Ki-67表达的相关性。结果:高级别组的ADC值、FA值、rADC值和rFA值低于中低级别组(P0.05)。高级别组病理组织中VEGF、Ki-67的阳性表达率高于中低级别组(P0.05)。经Spearman相关分析显示,ADC值、FA值、rADC值和rFA值与VEGF、Ki-67的表达水平均呈负相关(P0.05)。结论:DTI定量参数与脑胶质瘤病理分级和VEGF、Ki-67的表达水平密切相关。  相似文献   
109.
Ovarian carcinomas relate to highest death rate in gynecologic malignancies as absence of symptoms shield the disease in the early stage. Current evidences have been devoted to discovering early effective screening mechanism prior to the onset of clinical symptoms. Therefore, biomarkers are the crucial tools that are capable of predicting progression, risk stratification and overall therapeutic benefit to fight against this deadly disease. Although recent studies have revealed serum protein markers, CA-125, HE4, mesothelin etc. have higher sensitivity and specificity at the early stages of the cancer; the critical questions arise regarding the applicability and reproducibility of genomic profiling across different patient groups. Hence, our hypothesis is that the panels of signature biomarkers will be much more effective to improve the diagnosis and prediction of patient survival outcome with high sensitivity and specificity. Ovarian cancer is heterogeneous in nature and contain a sub-population of stem cell-like characteristics that has the ability to grow as anchorage-independent manner and subsequently is able to metastasize. Highly tumorigenic and chemotherapy-resistant cancer stem cells (CSCs)-specific biomarkers therefore reflects the interesting possibilities to be targeted to minimize the high frequency of relapse and resistance to drugs. Several putative ovarian CSC markers such as CD24, CD44, CD133, SSEA have already been proposed in recent studies, yet, a large panel of updated biomarkers have high clinical relevance to define the prospective isolation of viable circulating CSCs. Therefore, this review highlights current evidence based updated ovarian cancer specific prognostic and diagnostic biomarkers and potential importance of CSCs in context of tumorigenicity and metastatic activity for fundamental biological and clinical implications.  相似文献   
110.
OBJECT: Nowadays, there is increasing evidence that functional magnetic resonance imaging (MRI) modalities, namely, diffusion-weighted imaging (DWI) and dynamic-contrast enhanced MRI (DCE MRI), can characterize tumor architecture like cellularity and vascularity. Previously, two formulas based on a logistic tumor growth model were proposed to predict tumor cellularity with DWI and DCE. The purpose of this study was to proof these formulas. METHODS: 16 patients with head and neck squamous cell carcinomas were included into the study. There were 2 women and 14 men with a mean age of 57.0 ± 7.5 years. In every case, tumor cellularity was calculated using the proposed formulas by Atuegwu et al. In every case, also tumor cell count was estimated on histopathological specimens as an average cell count per 2 to 5 high-power fields. RESULTS: There was no significant correlation between the calculated cellularity and histopathologically estimated cell count by using the formula based on apparent diffusion coefficient (ADC) values. A moderate positive correlation (r=0.515, P=.041) could be identified by using the formula including ADC and Ve values. CONCLUSIONS: The formula including ADC and Ve values is more sensitive to predict tumor cellularity than the formula including ADC values only.  相似文献   
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