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21.
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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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   
26.
Shields  JB; Holtz  S 《Radiology》1976,120(1):19
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诺氟沙星在0.05mol·L-1NH4Cl (pH 5.8)溶液中,出现一灵敏的示波极谱还原峰。峰电位为-1.44 V (vs SCE)。峰高与诺氟沙星的浓度在1.0×10-7~4.0×10-6mol·L-1范围内成正比,检出限为5.0×10-8mol·L-1,并用于样品的测定。用线性扫描与循环伏安法等手段研究体系的吸附性质。实验表明,该电极过程为具有吸附性的不可逆过程。  相似文献   
29.
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   
30.
临床资料 2003-02/2004—10,难治性青光眼36例36眼,(男19,女17)例;年龄37—81(平均59.6)岁;术前视力:无光感6例,光感15例,手动13例,眼前数指2例;术前眼压:在5.59—10.77(平均8.01)kPa;1例系玻切术后继发性青光眼,35例系新生血管性青光眼(其中:视网膜静脉阻塞15例,糖尿病视网膜病变18例,原因不明2例).①眼内窥镜下睫状体光凝术18例:在角膜缘环形剪开结膜,充分止血;在  相似文献   
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