流式细胞仪与镜检法计数网织红细胞的比较

目的建立流式细胞仪计数网织红细胞的方法并应用于临床。方法5ul全血加入噻唑橙染液中，流式细胞仪计数10万个红细胞，分析其中的网织红细胞数并与镜检法比较。结果流式细胞仪法与镜检法计数网织红细胞结果差异无显著性。结论流式细胞仪计数网织红细胞快速．结果准确．且重复性好，适合临床常规检测网织红细胞。     

Carbohydrate counting in diabetes

Carbohydrate counting is an effective tool to aid the management of blood glucose control in type 1 diabetes. All those with this condition should be offered the opportunity to learn about carbohydrate counting at diagnosis and have access to structured education programmes such as Dose Adjustment for Normal Eating (DAFNE).     

血液分析仪及手工法计数血小板的影响因素分析

血细胞分析仪进行血小板计数的影响因素甚多 ,笔者在工作中就几种常见因素作了观察分析 ,报道如下。材料与方法1　标本　健康体检者血标本 45份 ;小细胞性贫血患者标本 2 5份 ;溶血标本 2 7份 ;低血小板患者 6份。2　方法　仪器法血小板计数采用美国雅培 CD-1 60 0型血细胞分析仪及进口配套试剂 ;手工法采用显微镜计数 ,采用许汝和法[1 ] 。2　在 8℃条件下 ,对 45份健康体检者 EDTA-K2 抗凝静脉血 ,用血细胞分析仪进行血小板计数 ,结果为 ( 1 0 7± 76.5 )×1 0 9/ L,手工法为 ( 1 95± 68.2 )× 1 0 9/ L,经统计学分析 ,t=5 .76,P<0 .…     

Ultrasensitive flow-based immunoassays using single-molecule counting

BACKGROUND: Immunoassay (IA) technology has expanded the clinical utility of protein biomarkers, but demands for increased sensitivity, dynamic reporting ranges, and small sample volumes have limited the potential clinical usefulness of many biomarkers. We assessed the performance, including limits of detection (LODs) and the dynamic reporting range, of an IA-based technology, Erenna Immunoassay System, for a series of biomarkers, including cardiac troponin I (cTnI). METHODS: Erenna IAs were used with 10 different and clinically important biomarkers to ascertain the LOD with various sample sizes (10 microL to 200 microL). RESULTS: The Erenna Immunoassay System generated LODs of 10-100 pg/L using 100 microL of sample. For cTnI, the LOD was 0.2 ng/L and a 10% CV was seen between 0.78 and 1.6 ng/L. CONCLUSIONS: The Erenna IA-based technology reproducibly measures protein biomarkers with detection limits of 10-100 pg/L, with a dynamic range of >4.5 logs in sample volumes of 50-150 microL.     

Effect of counting errors on immunoassay precision

Using mathematical analysis and computer simulation, we studied the effect of gamma scintillation counting error on two radioimmunoassays (RIAs) and an immunoradiometric assay (IRMA). To analyze the propagation of the counting errors into the estimation of analyte concentration, we empirically derived parameters for logit-log data-reduction models for assays of digoxin and triiodothyronine (RIAs) and ferritin (IRMA). The component of the analytical error attributable to counting variability, when expressed as a CV of the analyte concentration, decreased approximately linearly with the inverse of the square root of the maximum counts bound. Larger counting-error CVs were found at lower concentrations for both RIAs and the IRMA. Substantially smaller CVs for overall assay were found when the maximum counts bound progressively increased from 500 to 10,000 counts, but further increases in maximum bound counts resulted in little decrease in overall assay CV except when very low concentrations of analyte were being measured. Therefore, RIA and IRMA systems based in duplicate determinations having at least 10,000 maximum counts bound should have adequate precision, except possibly at very low concentrations.     

Platelet counting using plasma platelet concentrate samples

Platelet counting using samples of plasma from platelet concentrates prepared for transfusion was assessed. The methods employed included a manual phase-contrast method, and counting with Coulter S Plus and Sysmex E-2500 counters. All methods were reproducible (mean CV of 4.9, 2.2 and 1.4%, respectively). However, neat samples of platelet concentrates analysed by Coulter counter were inaccurate (mean count of 863.8 x 10(9)/l compared to 1018.9 x 10(9)/l counted manually). Moreover, the Coulter platelet counts were non-linear above 900 x 10(9)/l, whereas the E-2500 platelet counts were linear to 2700 x 10(9)/l. A one-in-three pre-dilution was required to obtain accurate, linear counts with the Coulter counter, whereas the E-2500 was accurate without pre-dilution (mean count of 1030.2 x 10(9)/l compared to 1018.9 x 10(9)/l counted manually). In conclusion, the method of platelet counting may affect true platelet yields.