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Recently, an assay for detection of proviral HIV-1 DNA in leukocytes became commercially available. This assay (Amplicor HIV-1 test, Roche Diagnostic Systems) multiplies HIV-1 DNA up to a detectable level, using the polymerase chain reaction. We studied performance of this assay on 74 samples from HIV-1-infected patients and on 41 samples from healthy blood donors. Twice a negative control sample appeared to be erroneously reactive. However, sensitivity and specificity on the patient and donor samples both were 100%. To avoid false-positive results, we advise to repeat initially reactive samples if no other data confirm HIV-infection.  相似文献   
3.
目的 应用经食管超声多普勒血液动力学监测仪 ,观察全麻下急性高容量血液稀释(HHD)的血液动力学和氧供 (DO2 )变化。方法 选择 1 5例ASAI~II级择期行非心脏手术患者。麻醉诱导插管后持续监测心输出量 (CO)、每搏量 (SV)、心脏指数 (CI)、血流峰速度 (PV)、血流加速度(Acc)和左室射血时间指数 (LVETi) ,每隔 5分钟输入MAP值后计算出系统血管阻力 (SVR)值。麻醉平稳和各项监测完成后 1 0min ,在 30min内输注 6 %羟乙基淀粉 (HES) 2 0ml/kg。记录 6 %HES输注前、输注 1 5和 30min时的各项监测数据 ,并抽取动脉血液样本行血气分析并计算DO2 。结果 与HHD前相比 ,血气各参数 (pH、PaO2 、PaCO2 、BE)均无明显差异 (P >0 0 5 ) ,而 6 %HES输注 1 5和30min血红蛋白 (Hb)含量、红细胞比积 (Hct)均明显下降 (P <0 0 5和P <0 0 1 )。 6 %HES输注 1 5和 30min时的CaO2 比HHD前明显下降 (P <0 0 5 ) ,而DO2 显著增加 (P <0 0 5 )。与HHD前测量值相比 ,6 %HES输注 1 5min ,CO、SV、CI、PV和Acc明显升高 ,SVR显著降低 (P <0 0 5 ) ;6 %HES输注 30min ,SV、PV和Acc进一步升高 (P <0 0 1 ) ,而CO、CI和SVR与 6 %HES输注 1 5min时无明显变化。MAP、HR和LVETi在HHD期间无明显变化。结论 术前输注 6 %HES 2 0ml  相似文献   
4.
A group of 5,000 patients, suspected of haemolytic anaemia, were investigated with molecular genetic methods for deletion types of alpha-thalassemia. In 776 (15.6%) patients a deletion of one or more alpha-globin genes was found. The same group of patients was also investigated for abnormal haemoglobins and beta-thalassaemia. In about 30% of the patients either an alpha-thalassaemia, an abnormal haemoglobin, a beta-thalassaemia, or a combination was diagnosed. In a group of patients with a haemoglobinopathy, the frequency of alpha-thalassaemia was much higher (i.e. 33%) than in individuals without haemoglobinopathy. Preselection of the patients based on the presence of microcytic erythrocytes and/or a decreased ADW0.5 of the erythrocytes gave a high incidence of false-negative and false-positive results. Therefore, haemoglobin examination should not be restricted to protein chemistry, but should include molecular genetic investigations for deletion types of alpha-thalassaemia.  相似文献   
5.
Genetic mapping ofPim-1 putative oncogene to mouse chromosome 17   总被引:10,自引:0,他引:10  
Pim-1 is a putative oncogene activated in T-cell lymphomas induced by Moloney and AKR mink cell focus forming (MCF) viruses. We have determined the chromosomal localization of the Pim-1gene in mice by Southern blot analysis of DNAs obtained from a panel of mouse-Chinese hamster somatic cell hybrids. The Pim-1gene was localized on chromosome 17, a chromosome frequently aberrant in T-cell lymphomas. Two chromosomal regions, containing sequences homologous to regions within the Pim-1locus, were localized on chromosome 6 and 16.  相似文献   
6.
We have noticed that suboptimal specimen processing and storage conditions may cause false-negative results in the detection of hepatitis C virus (HCV) RNA in plasma or serum. To establish the influence of specimen handling in a serological laboratory on the rate of detection of HCV RNA by the cDNA polymerase chain reaction (cDNA-PCR), we tested routine serum samples and fresh-frozen plasma samples from the same bleeding from confirmed anti-HCV-positive blood donors. When primers from the NS3/NS4 region were used, HCV RNA was detected in fresh-frozen plasma from 67% of the donors, whereas positive results were obtained with only 50% of the serum samples that had been subjected to routine serological procedures. Analysis of the same samples with primers from the highly conserved 5'-terminal region (5'-TR) revealed an HCV RNA detection rate of 92% for both the routine and the fresh-frozen samples. However, the yield of the amplification product in routine samples was strongly reduced compared with that in fresh-frozen plasma. Comparison of both primer sets for cDNA-PCR showed that the 5'-TR primer set was 10- to 100-fold more effective in detecting HCV RNA. We also analyzed the effect of storage of whole EDTA-blood and serum at room temperature and at 4 degrees C on the yield of the amplification product. A rapid decline in detectable HCV RNA of 3 to 4 log units was observed within 14 days when whole blood and serum were stored at room temperature. By contrast, no perceptible reduction in the cDNA-PCR signal was found in freshly prepared serum stored at 4 degrees C.  相似文献   
7.
Serum samples from 316 patients visiting the Dutch National Hemophilia Center were collected from 1979 to 1993 and stored at ?30°C. Patients were placed into three different groups: (1) patients ever treated with large pool non-hepatitis C virus (HCV)-safe concentrate (n=179); (2) patients treated with cryoprecipitate (n = 125); and (3) patients treated exclusively with HCV-save concentrate (n=12). In order to examine the prevalence of HCV infection in the different treatment groups serum samples were tested retrospectively for anti-HCV antibody using second generation enzyme-linked immunosorbent assay (ELISA) and recombinant immunoblot assay (RIBA-2). Significant differences in the prevalence of HCV infection were found between these 3 groups (group 1: 99%, group 2: 66%, group 3: 0%). The safety of currently administered clotting products is demonstrated in 57 patients who remained without HCV markers between 1989 and 1993. To examine the natural course of HCV infection fresh-frozen plasma samples were obtained recently from a subgroup of 277 hemophilia patients for HCV-RNA detection by a well-validated cDNA-PCR assay. In contrast to other reports, no evidence was found for seronegative HCV carriers. None of 52 patients without anti-HCV had detectable HCV-RNA. Of 225 patients with anti-HCV, 182 (81%) were HCV-RNA positive. None of 39 anti-HCV positive patients with a negative HCV-RNA reaction had serum alanine aminotransferase (ALT) levels above 50 U/l, whereas 44% of HCV-RNA positive patients had persistently elevated ALT levels above 50 U/l. These results indicate that 20% of hemophilia patients who have been infected with HCV in the past eliminated the virus or have viral replication below the detection limit of polymerase chain reaction (PCR) without biochemical evidence of liver damage. © 1995 Wiley-Liss, inc.  相似文献   
8.
BackgroundLong non-coding RNAs (lncRNAs) are essential regulators for various human cancers. However, these lncRNAs need to be further classified for cancer. In the present study, we identified novel competing endogenous RNA (ceRNA) network for bladder cancer (BC) and explored the gene functions of the ceRNA regulatory network.MethodsDifferential gene expression analysis were performed on The Cancer Genome Atlas Urothelial Bladder Carcinoma (TCGA-BLCA) datasets to identify differentially expressed messenger RNAs (mRNAs), lncRNAs, and microRNAs (miRNAs). Based on the competing endogenous RNA (ceRNA) hypothesis, a lncRNA-miRNA-mRNA network was constructed using the StarBase database and visualization by Cytoscape software. Functional enrichment analyses of Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway were performed via R package ClusterProfiler. The protein-protein interaction network was constructed by STRING database and visualization by Cytoscape. Finally, we used CIBERSORT and the TIMER database to analyze the immune infiltrations for BC.ResultsThe regulatory network was constructed via TCGA BLCA cohort. The differential expressions of lncRNA, miRNA, and mRNA were 186, 200, and 2,661, respectively. There were 106 lncRNA, miRNA, and mRNA included in the ceRNA network. In this network, Calcium Voltage-gated Channel Auxiliary Subunit Alpha2delta1 (CACNA2D1, P<0.001), domain containing engulfment adaptor1 (GULP1, P=0.001), latent transforming growth factor beta binding protein 1 (LTBP1, P=0.006), myosin light chain kinase (MYLK, P=0.001), serpin family E member 2 (SERPINE2, P=0.002), spectrin beta non-erythrocytic 2 (SPTBN2, P=0.047), and hsa-miR-590-3p (P<0.001) significantly affected the prognosis of BC patients. Functional enrichment analyses showed that the biological functions included negative regulation of protein phosphorylation, cell morphogenesis, and sensory organ morphogenesis. Important cancer pathways of KEGG included parathyroid hormone synthesis secretion action, the notch signaling pathway, MAPK signaling pathway, the Rap1 signaling pathway, signaling pathways regulating the pluripotency of stem cells, and the transforming growth factor-β signaling pathway. Our findings demonstrated that the ceRNA network has important biological functions and a significant influence on the prognosis of BC.ConclusionsThe lncRNA-miRNA-mRNA network constructed in the present study could provide useful insight into the underlying tumorigenesis of BC, and can determine new molecular biomarkers for the diagnosis and therapeutical treatment of BC.  相似文献   
9.
Background: Prognostically favorable factors for epiretinal membrane removal have been described in the literature by several authors. Little information, however, is available about the objective assessment of the preoperative macular function. This study reports the results of idiopathic epiretinal membrane removal and the prognostic value of preoperative pattern reversal visual-evoked potentials (PRVEPS) in recovery of visual acuity (VA). Methods: In 60 patients (60 eyes) with idiopathic epiretinal membrane we performed PRVEP examination preoperatively. All eyes were operated on by standard three-port vitrectomy with membrane removal. Two eyes were excluded because of postoperative complications. Follow-up VA was compared with preoperative VA for the 58 study eyes and correlated with preoperative PRVEP parameters. Results: The mean preoperative VA was 0.2, the mean postoperative VA, 0.4. The PRVEP was recordable in 74%, 67% and 36% of cases for check sizes of 17, 10 and 7 arcmin respectively. Twenty patients (50%) had an increase in VA of two lines or more, in 25 patients (43%) VA remained within one line of the preoperative value, and in 4 patients (7%) VA decreased by two lines or more. The mean preoperative VA was not significantly different between the group with an improved VA and the group that did not benefit from membrane removal. Of the PRVEP parameters, only the N80 latency for the 17' check size was significantly associated with postoperative visual outcome. Conclusion: The PRVEP is applicable as a predictor for visual outcome in cases of epiretinal membrane removal. For the 17' pattern size we found a significant association of the combination of recordability and delayed N80 latency with visual outcome.  相似文献   
10.
To investigate the discriminative power of pattern-reversal visual evoked potential characteristics (peak latencies and amplitude) and to test whether the addition of visual evoked potential amplitude can increase the power of the visual evoked potential in the diagnosis of multiple sclerosis, we retrospectively studied visual evoked potentials in 59 patients with definite multiple sclerosis and 126 control subjects. Two check sizes (17 and 10) were used. Females had significantly higher amplitudes and shorter latencies than males. N80 latency showed a gradual increase and P100 amplitude a decrease with age. P100 latency was stable between the ages of 20 and 55 years but was increased in childhood and the elderly. The significance of visual evoked potential peak latencies and amplitude in separating the two groups was investigated by means of a (multivariate) discriminant analysis. The visual evoked potential with a pattern of 10 could be measured in 58% of patients with multiple sclerosis. The exclusive use of the P100 amplitude in the discriminant analysis resulted in a percentage of correctly classified cases of 84%, whereas for P100 and N80 latency it was 85% and 90%, respectively. With the 17 pattern, the N80 latency yielded also a higher correct percentage than did the P100 latency. Although N80 latency is, to a greater extent than P100 latency, influenced by age, sex and size of stimulus pattern, when these influences are accounted for, the N80 latency is a more sensitive measure than P100 latency in the classification of multiple sclerosis. Combined use of latency and amplitude for discriminant analysis yielded no significant improvement of the percentage of correctly classified cases.Abbreviations MS multiple sclerosis - SD standard deviation  相似文献   
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