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21.
Detection of anti-HTLV-I Tax antibodies in HTLV-I enzyme-linked immunosorbent assay-negative individuals 总被引:10,自引:0,他引:10
Ehrlich GD; Glaser JB; Abbott MA; Slamon DJ; Keith D; Sliwkowski M; Brandis J; Keitelman E; Teramoto Y; Papsidero L 《Blood》1989,74(3):1066-1072
The HTLV-I tax gene protein (Tax) is not packaged within the mature viral particle from which the proteins for the commercially available enzyme-linked immunosorbent assay (ELISA) are derived. Screening of 162 individuals within a cohort of white intravenous (IV) drug abusers, previously identified as having an increased incidence of HTLV-I infection, demonstrated that seven of them had antibodies to the HTLV-I Tax protein but tested negative in HTLV-I ELISAs and Western blots prepared from purified virion proteins. Three out of 35 individuals in other behaviorally defined high-risk groups also displayed this limited pattern of reactivity to HTLV-I proteins. The presence of the anti-HTLV- I p40/Tax antibodies was determined by radioimmunoprecipitation assay (RIPA), which also revealed low levels of anti-env reactivity. The specificity of the anti-p40 reactivity was confirmed on specific Tax ELISAs and Western blots prepared from recombinantly produced Tax. In vitro gene amplification by the polymerase chain reaction (PCR) was used to establish the presence of sequences homologous to HTLV-I proviral DNA in four/four of these HTLV-I ELISA negative, Tax ELISA/Tax western blot/RIPA positive individuals. These data suggest that the true incidence of HTLV-I infection within high-risk cohorts is greater than previously reported. 相似文献
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EG Burden RW Walker DJ Ferguson AMF Goubran JR Howell JB John F Khan JS McGrath JP Evans 《Annals of the Royal College of Surgeons of England》2021,103(3):173
IntroductionWith the emergence of the COVID-19 pandemic, all elective surgery was temporarily suspended in the UK, allowing for diversion of resource to manage the anticipated surge of critically unwell patients. Continuing to deliver time-critical surgical care is important to avoid excess morbidity and mortality from pathologies unrelated to COVID-19. We describe the implementation and short-term surgical outcomes from a system to deliver time-critical elective surgical care to patients during the COVID-19 pandemic.Materials and methodsA protocol for the prioritisation and safe delivery of time-critical surgery at a COVID-19 ‘clean’ site was implemented at the Nuffield Health Exeter Hospital, an independent sector hospital in the southwest of England. Outcomes to 30 days postoperatively were recorded, including unplanned admissions after daycase surgery, readmissions and complications, as well as the incidence of perioperative COVID-19 infection in patients and staff.ResultsA total of 128 surgical procedures were performed during a 31-day period by a range of specialties including breast, plastics, urology, gynaecology, vascular and cardiology. There was one unplanned admission and and two readmissions. Six complications were identified, and all were Clavien-Dindo grade 1 or 2. All 128 patients had preoperative COVID-19 swabs, one of which was positive and the patient had their surgery delayed. Ten patients were tested for COVID-19 postoperatively, with none testing positive.ConclusionThis study has demonstrated the implementation of a safe system for delivery of time-critical elective surgical care at a COVID-19 clean site. Other healthcare providers may benefit from implementation of similar methodology as hospitals plan to restart elective surgery. 相似文献
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为了寻找抗生育药物,从17β-羟基-7α-甲基-4-雌烯-3-酮经17β-羟基-7α-甲基-4β,5β-环氧雌烷-3-酮合成了七个4-位取代的目标化合物:4,17β-二羟基-7α-甲基-4-雌烯-3-酮及其17-乙酸酯、4-甲氧基-17β-羟基-7α-甲基-4-雌烯-3-酮及其17-乙酸酯、4-氯-17β-羟基-7α-甲基-4-雌烯-3-酮及其17-乙酸酯和4-溴-17β-羟基-7α-甲基-4-雌烯-3-酮。这些化合物均可竞争性地与人蜕膜孕酮受体结合,并能抑制蜕膜细胞的发育,对大鼠具有显著的抗着床活性。 相似文献
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M McCarthy JB Yuan A Campbell NP Lenzo K Butler‐Henderson 《Journal of Medical Imaging and Radiation Oncology》2008,52(6):564-569
18F‐fluorodeoxyglucose positron emission tomography (FDG‐PET) scans in the first 49 patients referred with either possible brain tumour or brain tumour recurrence were reviewed. FDG‐PET imaging was reported with reference to anatomical imaging. Based on the report the FDG study was classified as either positive or negative for the presence of tumour. Thirty‐eight cases were included in the analysis, 21 having pathological data and 17 with diagnostic clinical follow up. Eleven were excluded, as they had inadequate follow‐up data. Of the 21 cases with pathology, 18 were shown to have tumour. In this group there were five false‐negative scans and two false‐positive PET scans. Seventeen cases were assessed by clinical follow up, nine were considered to have been tumour. There were two false negatives with one false positive. The overall sensitivity, specificity and positive and negative predictive values were 74, 73, 87 and 53% respectively. This is similar to figures previously quoted in published work. Despite relatively limited numbers, the utility of FDG PET imaging in our hands is similar to published reports. With a positive predictive value of 87%, a positive FDG study indicates a high likelihood that there is brain tumour present. A negative study does not exclude the presence of tumour. 相似文献
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