Thinking about development of multi-channel surveillance and multi-dimensional early warning system of emerging respiratory communicable diseases / 中华流行病学杂志

The world has paid a heavy price for the pandemic of the emerging respiratory communicable disease, so more concern about communicable disease surveillance and early warning has been aroused. This paper briefly reviews the establishment of the surveillance and early warning system of respiratory communicable diseases in China, discusses its future development and introduces the novel surveillance methods and early warning models for the purpose of establishment of a multi-channel surveillance and multi-dimensional early warning system of communicable diseases in the future and the improvement of the prevention and control of emerging respiratory communicable diseases in China.

Exosomes and their roles in diabetes mellitus and its complications: from pathogenic, diagnostic and therapeutical perspectives / 生理学报

Exosome is a kind of nanoscale-size extracellular vesicles secreted by the means of cell active stimulation with outer membrane structure of vacuoles corpuscle. It can carry and transfer a lot of biological molecules, such as DNA fragments, circular RNA (circRNA), messenger RNA (mRNA), microRNA (miRNA), functional proteins, transcription factors, etc., so as to achieve the goal of information transmission between cells. The relationship between exosomes and diabetes has received extensive attention in recent years. The exosomes play an important role in insulin sensitivity, glucose homeostasis and vascular endothelial function. This paper reviews the role of exosomes in the occurrence and development of diabetes and its complications, and discusses the role and prospect of exosomes as a target for diabetes treatment and its role in the diagnosis and treatment of diabetes.

Short-term reproducibility and impact factors of intravoxel incoherent motion parameters for lung cancer / 中国医学影像技术

Objective To prospectively evaluate the short-term test-retest reproducibility of intravoxel incoherent motion (IVIM) parameters for lung cancer,and to investigate its impact factors.Methods Thirty-eight lung cancer patients underwent twice free breathing IVIM scanning (0.5-1.0 h interval).Two radiologists independently analyzed IVIM images to obtain true diffusion coefficient (D),pseudo-diffusion coefficient (D*) and perfusion fraction (f).All the parameters were compared between repeated measurements and scans.Intra-and inter-observer,test-retest reproducibility was assessed with interclass correlation coefficients (ICCs).The impact of lung cancer type (peripheral and central),size (the largest diameter ≥2 cm and ＜2 cm) and location (upper,mid,and lower lung field) on short-term reproducibility were compared by using coefficient of variations (WCVs).Results There was no significant difference between repeated measurements for all parameters (all P＞ 0.05).All the parameters showed good intra-and inter-observer agreement.WCVsof D* and f (19.88％-36.83％) were higher than those of D (2.97％-4.62％).WCVs of D were higher for central lung cancer and the largest diameter ＜2 cm,and increasing from apical to lower zone.WCV of f was larger in the central lung cancer and the largest diameter ≥2 cm,while D* was greatly influenced by type,size and location of lung cancer.Conclusion The test retest reproducibility of D is good,while of D* and f are poor in lung cancer.The type,size and location of lung cancers are the impact factors of IVIM parameters.

Evaluation by damped least-square algorithm on target identification ability of intracranial focal bidirectional electrical impedance perturbation / 医疗卫生装备

Objective To evaluate the effect of damped least-square algorithm on the identification of focal bidirectional electrical impedance perturbation in the intracranial area, and to analyze the influence of this kind of perturbation on the reconstruction quality of electrical impedance tomography. Methods Focal bidirectional electrical impedance perturbation was built based on the three-dimensional model and damped least-square algorithm was introduced into imaging. The position error and resolution were used to evaluate the imaging performance.Results When the focal electrical impedance perturbation existed,the target whose conductivity varied greatly or volume was large was more likely to be identified in the images while the target with smaller volume or variable conductivity presented in the reconstruction image was not obvious. It's pointed out that it may cause reconstruction images in some cases could not truly reflect the location and change information of the object of primary cerebral hemorrhage.At the same time,it affected the reconstruction precision,causing the position error and resolution with large fluctuation. Conclusion In reconstruction algorithm linearity correct matrix introduced for bidirectional electrical impedance perturbation contributes to enhancing the recognition of bidirectional perturbation, so that the characterization of the electrical impedance imaging can be augmented for clinical intracerebral hemorrhage.

Method for synchronous measurement of multichannel electrode-scalp contact impedances in brain EIT / 医疗卫生装备

Objective To study a method for monitoring multichannel electrode-scalp contact impedances in electrical impedance tomography (EIT), and to provide support for exploring the impact of contact impedances on imaging and the suppression method.Methods A reference electrode was introduced for the system,placed on the back of the neck or the top of the head. In the spare time of boundary voltage signal acquisition phase, the method of two electrodes was adopted to measure the electrical impedance between each imaging electrode and reference electrode, which was used to analyze the characteristics of multichannel contact impedances.Based on the existing EIT hardware system,the module for monitoring multichannel contact impedance was implemented.Results The calibration board test showed that the measurement error of this method was less than 1‰,and the maximum relative fluctuation of the measurement result within 10 hours was less than 1‰. Preliminary human test indicated that this method had the ability to obtain two kinds of information about spatial consistency and temporal stability of 16-channel contact impedances. Conclusion This method has high accuracy and stability,so it meets the requirements of monitoring multichannel contact impedances in brain EIT.

The value of diffusion-weighted imaging based on monoexponential and biexponential model in predicting the response of chemotherapy in non-small cell lung cancer patients / 中华放射学杂志

Objective To investigate the ADC value and intravoxel incoherent motion (IVIM) parameters to predict the early response to chemotherapy in patients with locally advanced non-small cell lung cancer (NSCLC). Methods Twenty-six patients with pathologically confirmed NSCLC in our hospital from June 2015 to January 2017 were prospectively studied. MR routine scan, DWI and IVIM scans were performed before and at the end of the first cycle of chemotherapy. The ADC value, pure diffusion parameter (D), perfusion parameter (D*) and perfusion fraction (f) before and after chemotherapy were recorded respectively, and the maximum diameter of tumor (MDMRI) was measured on T2WI. The effective group and the ineffective group were divided according to RECIST 1.1. Intra- and interobserver reproducibility were assessed with intraclass correlation coefficient (ICC). The differences of the parameters and their change rate were compared pre-and posttreatment, in the effective and the ineffective groups by using t test. Receiver operating characteristic (ROC) curves were generated to explore the optimal parameters and thresholds for early prediction of the efficacy of chemotherapy. Z test was used to compare the differences in the areas under the ROC curves. Results The repeatability of D*was relatively poor (ICC 0.507-0.716). The ADC and D values of the effective group before chemotherapy were (1.28±0.21)×10-3 and (1.05±0.14)×10-3mm2/s, respectively, and those of the ineffective group were (1.55 ± 0.25) × 10-3 and (1.29 ± 0.18) × 10-3mm2/s, respectively. The differences between two groups were statistically significant (t=-2.989, -3.755, respectively, P all<0.05). While there was no significant difference in f between the effective and ineffective groups before chemotherapy (t=-1.034, P=0.312). The ADC, D and f values of the effective group before chemotherapy were lower than those after chemotherapy, and the differences were statistically significant (t=-3.969,-5.617 and-2.876, respectively, P all<0.05). While there was no significant difference in ADC and D values in ineffective group (t=-0.737, -0.866, P>0.05, respectively). The difference of f was statistically significant (t=-2.731, P<0.05).ΔADC％,ΔD％andΔMDMRI％in effective group were (23.90 ± 22.28)％, (32.58 ± 20.63)％ and (18.77 ± 10.36)％, respectively, and those in ineffective group were (1.19 ± 11.35)％, (6.22 ± 21.63)％ and (9.35 ± 8.26)％, respectively. The differences between two groups were statistically significant (t=3.393, 3.154 and 2.487, respectively, P all<0.05). There was no significant difference inΔf％between two groups (t=1.346, P=0.191). ROC curve analysis showed that the area under curve (AUC) of preADC, preD, ΔADC％, ΔD％ and ΔMDMRI％ was 0.788, 0.848, 0.800, 0.830 and 0.727, respectively. When setting the preD=1.20×10-3 mm2/s as the boundary under the largest AUC, however, there was no significant differences in AUC compared with preADC, ΔADC％, ΔD％ and ΔMDMRI％ (Z=1.336, 0.363, 0.136, 1.395, P>0.05). Conclusion The ADC value, D value before chemotherapy and the early change rate after chemotherapy can better predict the early response of chemotherapy in NSCLC patients.

Value of endobronchial ultrasound elastography in the diagnosis of mediastinal and hilar lymph node metastasis in lung cancer / 中南大学学报(医学版)

OBJECTIVE@#To assess the value of endobronchial ultrasound elastography in the diagnosis of mediastinal and hilar lymph node metastasis in lung cancer. 
@*METHODS@#A total of 40 patients with lung cancer underwent ultrasonic bronchoscope examination before operation. Elastography and standard endobronchial ultrasound (EBUS) of lymph nodes were performed before EBUS-guided transbronchial needle aspiration (EBUS-TBNA). The elastography characteristics was compared between benign and malignant lymph nodes. The diagnosis accuracy in malignant lymph nodes was also compared between the elastography and the standard EBUS. The value of the elastography was assessed in distinguishing the benign and malignant lymph nodes.
@*RESULTS@#1) The significant indicators of standard EBUS in diagnosis of malignant lymph nodes were hypoechonic nodes, uneven echo, distinct boundary and short diameter greater than 1 cm (all P<0.01). 2) There was significant difference in the elastosonography grading score between benign and malignant lymph nodes (P<0.01). 3) The elastography grading score was more sensitive and specific in determining the malignant lymph node than the standard EBUS criteria. The area under the receiver operating characteristic curve (AUC) was maximal when the elastography grading score was ≥2.5. The specificity, sensitivity, positive predictive value, negative predictive value of elastography grading score was 76.9%, 85.7%, 85.7% and 76.9% in distinguishing malignant and benign nodes. The overall accuracy of elastography grading score was 82.3%. The combination of elastography grading score, low echo, distinct boundary and short diameter greater than 1 cm showed the best diagnostic efficiency value. The AUC was 0.911. In distinguishing malignant and benign nodes, the specificity, sensitivity, positive predictive value, negative predictive value and accuracy of the combined indexes was 84.6%, 88.1%, 90.2%, and 81.5% respectively. The overall accuracy was 86.8%.
@*CONCLUSION@#The endobronchial ultrasound elastography can effectively distinguish the mediastinal and hilar lymph node metastasis in lung cancer. The diagnosis accuracy of elastography in malignant lymph node is higher than that of standard EBUS criteria. The combination of elastosonography grading score and standard EBUS criteria can improve the diagnostic efficiency.

Endobronchial Ultrasound Elastography for Diagnosing Mediastinal and Hilar Lymph Nodes / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Pathophysiological processes, such as malignancy, can lead to the formation of stiffer tissue in lung cancers. Endobronchial ultrasound (EBUS) elastography is a novel technique for measuring tissue stiffness during EBUS-guided transbronchial needle aspiration (EBUS-TBNA). The current study was conducted to investigate the diagnostic value of EBUS elastography for mediastinal and hilar lymph node metastasis in lung cancers.</p><p><b>METHODS</b>From January 2014 to January 2015, 40 patients suspected of lung cancer were enrolled, and a total of 68 lymph nodes were evaluated by EBUS-TBNA. EBUS-guided elastography of lymph nodes was performed prior to EBUS-TBNA. Standard EBUS characteristics were also described. Pathological determination of malignant or benign lymph nodes was used as the gold standard for this study. If EBUS-TBNA did not result in a formal pathological diagnosis of malignancy, patients were referred for a surgical procedure. Comparisons of elastography and standard EBUS characteristics were made between benign and malignant lymph nodes.</p><p><b>RESULTS</b>Elastography grading scores and strain ratios showed significant differences between benign and malignant lymph nodes (P = 0.000). The elastography strain ratio was more sensitive and specific for determining malignant lymph nodes than elastography grading score or standard EBUS criteria. The receiver operating characteristic curve for the elastography strain ratio showed an area under the curve of 0.933. The best cut-off point of the strain ratio for differentiating malignant from benign lymph nodes was 32.07. The elastography strain ratio had a sensitivity of 88.1%, the specificity of 80.8%, positive predictive value of 88.1%, and negative predictive value of 80.8% for distinguishing malignant from benign nodes. The overall accuracy of elastography strain ratio was 85.3%. The strain ratio of malignant and benign lymph nodes positively correlated with the elastography grading score (r = 0.561, P = 0.000).</p><p><b>CONCLUSIONS</b>EBUS elastography can be effectively used to predict mediastinal and hilar lymph node metastases in lung cancer. This noninvasive technique may thus complement standard EBUS and help guide EBUS-TBNA procedures.</p>

Preliminary evaluation of antihyperglycemic effect of Rhizoma Coptidis alkaloids and their structure-activity relationships / 中国药理学通报

Aim To find the material foundation of treatment for diabetes in Coptidis Rhizoma ( RC ) . Methods The antihyperglycemic effect of RC alka-loids ( berberine, coptisine, palmatine, epiberberine, and jatrorrhizine) was evaluated in spontaneity diabe-tes KK-Ay mice. Results After 40 days′ oral admin-istration ( 225 mg · kg-1 · d-1 , ig ) , berberine and coptisine significantly suppressed the elevated fasting blood glucose level and ameliorated the glucose toler-ance . Body weight gain of KK-Ay mice was significant-ly decreased in the epiberberine-treated group. Berber-ine improved insulin resistance and jatrorrhizine in-creased the SOD activity, decreased the MDA level. Conclusions These results indicate that the main an-tihypoglycemic effect constituents are berberine and coptisine, while they show different mechanisms. Pal-matine, epiberberine and jatrorrhizine display different potential roles in the treatment of diabetes. The meth-ylene-dioxy groups at the C-2 , C-3 , C-9 and C-10 po-sitions are indispensable for antihyperglycemic effect of RC alkaloids.

High levels of interleukin-6 and 8-iso-prostaglandin in the exhaled breath condensate and serum of patients with chronic obstructive pulmonary disease related pulmonary hypertension / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Pulmonary hypertension (PH) is a common complication of chronic obstructive pulmonary disease (COPD). Although alveolar hypoxia is considered as a main cause of PH in COPD, structural and functional changes of pulmonary circulation are apparent at the initial stage of COPD. We hypothesized that an inflammatory response and oxidative stress might contribute to the formation of PH in COPD.</p><p><b>METHODS</b>We measured the levels of interleukin-6 (IL-6) and 8-iso-prostaglandin (8-iso-PSG) in exhaled breath condensate (EBC) and serum in 40 patients with COPD only or in 45 patients with COPD combined with PH. Pulmonary arterial systolic pressure (PASP) was assessed by Doppler echocardiography and defined as PH when the value of systolic pressure was greater than 40 mmHg.</p><p><b>RESULTS</b>Compared with the COPD only group, the level of IL-6 in EBC was significantly increased in all 45 patients with COPD combined with PH ((8.27±2.14) ng/L vs. (4.95±1.19) ng/L, P < 0.01). The level of IL-6 in serum was also elevated in patients with COPD combined with PH compared with the COPD only group ((72.8±21.6) ng/L vs. (43.58±13.38) ng/L, P < 0.01). Similarly, we also observed a significant increase in the level of 8-iso-PSG in both EBC and serum in the COPD with PH group, compared with the COPD only group (EBC: (9.00±2.49) ng/L vs. (5.96±2.31) ng/L, P < 0.01 and serum: (41.87±9.75) ng/L vs. (27.79±11.09) ng/L, P < 0.01). Additionally, the value of PASP in the PH group was confirmed to be positively correlated with the increase in the levels of IL-6 and 8-iso-PSG in both EBC and serum (r = 0.477-0.589, P < 0.05).</p><p><b>CONCLUSION</b>The increase in the levels of IL-6 and 8-iso-PSG in EBC and serum correlates with the pathogenesis of PH in COPD.</p>

Comparison study of clinical effect and complications between subfascial and submammary breast augmentation / 中华整形外科杂志

<p><b>OBJECTIVE</b>To compare the clinical effect and complications of subfascial breast augmentation and submammary breast augmentation.</p><p><b>METHOD</b>From Sept. 2009 to May 2012 , 25 patients with subfascial breast augmentation and 31 patients with submammary breast augmentation were observed. The postoperative results including visible implant edge or ripple, upper pole of the implant and long-term implant ptosis were compared respectively. The complications including hematoma, infection and capsular contraction were also recorded.</p><p><b>RESULTS</b>56 cases were followed up for 2 months to 26 months. The incidence rate of visible implant edge or ripple was 4.0% (1/25 ) in the subfascial group and 29.0% (9/31) in the submammary group, showing a significant difference between them ( PC 0.05). The incidence rate of convex upper pole of the implant was 8.0% (2/25) in the subfascial group and 35.5% (11/31) in the submammary group, showing a significant difference between them ( P < 0.05). Long-term implant ptosis was not found in the two groups. The incidence rate of hematoma was 4.0% (1/25) in the subfascial group and 6.5% (2/31) in the submammary group, infection was not found. The incidence rate of capsular contraction was 8.0% (2/25) in the subfascial group and 12.9% (4/31) in the submammary group, showing no statistical difference between them ( P > 0.05 ).</p><p><b>CONCLUSIONS</b>Subfascial breast augmentation has more clinical advantages compared with submammary breast augmentation, but no evident difference was found in the common complication rate, such as capsular contraction.</p>

Effect of second-line treatment with capecitabine and thalidomide in patients with advanced pancreatic cancer / 中华肿瘤杂志

<p><b>OBJECTIVE</b>This study investigates the efficacy and tolerability of capecitabine plus thalidomide in patients with advanced pancreatic cancer who previously underwent gemcitabine-based therapy.</p><p><b>METHODS</b>Sixty-one patients with unresectable or metastatic PC who had progressed on single-agent Gem or a Gem-containing regimen were enrolled. The patients were randomly divided into two groups. One group (31 patients) was treated with capecitabine alone, and another group was treated with capecitabine plus thalidomide. Capecitabine was administered orally twice a day at a dose of 1, 250 mg/m(2) for 14-day followed by 7-day rest and oral thalidomide 100 mg was given daily without interruption until disease progression or occurrence of unacceptable toxicity.</p><p><b>RESULTS</b>The PFS was 2.8 months (95%CI 2.4 - 3.2) vs. 3.1 months (95%CI 2.6-3.6, P < 0.05) and the OS was 6.1 months (95%CI 5.3 - 6.9) vs. 6.3 months (95%CI 5.2 - 7.4, P = 0.426). In the capecitabine alone group, one patient experienced a partial response (PR), 10 patients showed stable disease (SD) and 20 patients had progressive disease (PD). The another group, two patients experienced a partial response (PR), 11 patients SD, and 17 patients PD. The disease control rates were 35.5% and 43.3%, respectively. The major adverse reaction in the two groups was grade 3 diarrhea.</p><p><b>CONCLUSION</b>Capecitabine plus thalidomide regimen is marginally effective and well tolerated in the second-line setting in patients with gemcitabine-refractory advanced pancreatic cancer.</p>

The study on high-resolution HLA and human cytomegalovirus (HCMV) viremia in bone marrow transplantation recipients / 中华实验和临床病毒学杂志

<p><b>OBJECTIVE</b>To study the correlation between high-resolution HLA-A * 1101, HLA-A * 0201, HLA-A * 2402, HLA-B * 4001, HLA-DRB1 * 0901 with HCMV pp65 antigenemia after bone marrow transplantation (BMT) in China.</p><p><b>METHODS</b>48 recipients doing BMT during 2009. 2-2010. 10 were selected in my hospital; HCMV pp65 was detected by ELISA or immunohistochemical methods. The frequency of HLA-A * 1101, HLA-A * 0201, HLA-A * 2402, HLA-B * 4001, HLA-DRB1 * 0901 alleles were determined by Polymerase chain reaction-sequence based typing (PCR - SBT).</p><p><b>RESULTS</b>(1) The BMT recipients were HCMV pp65 antigenic positive(100%); (2) The positive rate of HLA-A * 1101, HLA-A * 0201, HLA-A * 2402, HLA-B * 4001 showed no obvious difference between 12 lower antigenemia group and 36 higher antigenemia group, the positive rate: HLA-A * 1101 were 33.3% (8/24) and 20.8% (15/72), HLA-A * 0201 were 4.2% (1/24) and 13.9% (10/72), HLA-A * 2402 were 12.5% (3/24) and 19.4% (14/72), HLA-B* 4001 were 16.7% (4/24) and 12.5% (9/72); (3) HLA-DRB1 * 0901 positive rate in higher antigenemia group was higher than the lower (P = 0.048), the positive rate were 4.2% (1/24) and 19.4% (14/72); (4) HLA-DRB1 * 0901 recipients were higher pp65 antigenemia than HLA-A * 2402 recipients (P = 0.007) and HLA-A * 1101 recipients (P = 0.028), HLA-A * 0201 recipients were higher pp65 antigenemia than HLA-A * 2402 (P = 0.02), the pp65 antigenemia showed no obvious difference among the rest of high-resolution HLA groups (P > 0.05).</p><p><b>CONCLUSION</b>HLA-DRB1 * 0901 alleles might be correlated with BMT recipients happened higher pp65 antigenemia, HLA-A * 2402 alleles might be correlated with BMT recipients happened lower pp65 antigenemia.</p>

Purification and characteristics of creatininase from Arthrobacter sp / 生物工程学报

A creatininase produced from a Arthrobacter sp. was purified 145-fold by a series of steps including heat treatment, ammonium sulfate precipitation, DEAE-Cellulose ion-exchange and hydrophobic chromatography. The specific activity of the pure enzyme was 209u/mg. The subunit molecular mass of creatininase was estimated to be 33 700D by SDS-PAGE. The creatininase was stable in the pH range between 6.0 - 9.0 and below 60 degrees C . Its Km value for creatinine was estimated to be 21.14 mmol/L. The enzyme was markedly inactivated by incubation with 1 mmol/L of Hg2+, Ag2+, Li+, Cu2+ and 20 mmol/L of 1, 11-Phananthroline respectively. Activation was observed when the enzyme was incubated with 1 mmol/L of Co2+ and Mn2+.

Study on the properties of a novel glycine amino peptidase from Actinomucor elegans / 生物工程学报

The glycine amino peptidase of Actinomucor elegans was studied in this work. For the enzyme production Actinomucor elegans was cultured with an enzyme producing medium. Then the cells were collected and subjected to enzyme purification. The glycine aminopeptidase was purified 592 times by a DEAE-Toyopearl column, a Toyopearl HW 65-C column and a Superdex 200 column subsequently and the purified enzyme had a specific activity of 14.2 u/mg. The enzyme was estimated to have molecular mass of 320kD by gel filtration and a subunit size of 56.5kD by SDS-PAGE. It hydrolyzes glycine residue containing substrates such as glycine-betanaphthylamine more efficiently than those containing other amino acid residue. Addition to Gly-betaNA, the enzyme could also hydrolyze Ala-betaNA, Met-betaNA, Leu-betaNA, Arg-betaNA and Ser-betaNA but it had no activity on the substrates such as Trp-betaNA, Pyr-betaNA, Pro-betaNA, Asp-betaNA, Lys-betaNA, Val-betaNA. It was also observed when the glycine-betanaphthylamine concentration was higher than 2mmol/L the enzyme showed a substrate inhibition, and at the 20 mmol/L the enzyme only showed about 55% activity as it showed at the 2mmol/L. Whereas no such phenomenon was observed on the other substrate such as alanine-betanaphthylamine. The optimal temperature and pH for the reaction of this enzyme is 30 degrees C and pH 8.0, respectively. The Km and Kcat of the enzyme for glycine-betanaphthylamine is 0.24 mmol/L and 100.8 s(-1), respectively. Zn2+, Cu2+ and Cd2+ suppress almost all activities of the enzyme at the concentration of 1.0 mmol/L. Based on the study of chelating reagents, GAP belongs to the metalloenzyme. When a gelatin solution was hydrolyzed with 0.5% of alkaline proteinase together with glycine aminopeptidase at 50 degrees C for 18 hours, the glycine aminopeptidase could improve the hydrolysis degree of the protease. The total free amino acid was improved about 13% and although the enzyme mainly had the activity to hydrolyze the glycine residue, individual amino acids analysis with an amino acid analyzer showed that the contents of glycine, proline, alanine, arginine and glutamate were considerably increased. The results of this study showed that the glycine aminopeptidase would be useful in the food industry.

Study on the significance of S/Co ratio of a domestic reagent used for anti-hepatitis C virus antibody detection / 中华传染病杂志

Objective To study the significance of the sample S/Co ratio when using a domestic reagent for anti-hepatitis C virus(HCV)antibody detection and to explore the procedure and standard of anti-HCV antibody diagnosis by using this domestic reagent.Methods Anti-HCV antibody was detected in 295 000 blood donors by a domestic anti-HCV reagent with enzyme-linked immunosorbent assay(ELISA)method and the reactive samples were tested again by ortho anti-HCV antibody reagent.The samples which anti-HCV antibodies were determined as positive by ortho anti-HCV rea- gent were examined by recombinant immunoblot assay(RIBA)reagent and 106 samples of them were also tested for HCV RNA.Results Six hundred and eighty-one samples were reactive in 295 000 samples screened by the domestic ELISA reagent,the reactive ratio was 0.23 %.Among the reactive samples screened by the domestic ELISA reagent,367 samples were determined as positive by ortho anti-HCV reagent while 66.2% of them showed a S/Co ratio≥3.8.The consistency rate between positive results determined by the domestic reagent and RIBA reagent respectively was 53.8%.For the samples showing S/Co ratio≥3.8 by ortho anti-HCV reagent,94.2% had a S/Co ratio≥8.0 when using the domestic ELISA reagent,while the percentage of samples showing S/Co ratio