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61.
Tessa Timmers Rik Ossenkoppele Denise Visser Hayel Tuncel Emma E Wolters Sander CJ Verfaillie Wiesje M van der Flier Ronald Boellaard Sandeep SV Golla Bart NM van Berckel 《Journal of cerebral blood flow and metabolism》2020,40(12):2464
The aim of this study was to investigate the test–retest (TRT) repeatability of various parametric quantification methods for [18F]Flortaucipir positron emission tomography (PET). We included eight subjects with dementia or mild cognitive impairment due to Alzheimer’s disease and six cognitively normal subjects. All underwent two 130-min dynamic [18F]Flortaucipir PET scans within 3 ± 1 weeks. Data were analyzed using reference region models receptor parametric mapping (RPM), simplified reference tissue method 2 (SRTM2) and reference logan (RLogan), as well as standardized uptake value ratios (SUVr, time intervals 40–60, 80–100 and 110–130 min post-injection) with cerebellar gray matter as reference region. We obtained distribution volume ratio or SUVr, first for all brain regions and then in three tau-specific regions-of-interest (ROIs). TRT repeatability (%) was defined as |retest–test|/(average (test + retest)) × 100. For all methods and across ROIs, TRT repeatability ranged from (median (IQR)) 0.84% (0.68–2.15) to 6.84% (2.99–11.50). TRT repeatability was good for all reference methods used, although semi-quantitative models (i.e. SUVr) performed marginally worse than quantitative models, for instance TRT repeatability of RPM: 1.98% (0.78–3.58) vs. SUVr80–100: 3.05% (1.28–5.52), p < 0.001. Furthermore, for SUVr80–100 and SUVr110–130, with higher average SUVr, more variation was observed. In conclusion, while TRT repeatability was good for all models used, quantitative methods performed slightly better than semi-quantitative methods. 相似文献
62.
Pseudomonas aeruginosa is one of the most relevant nosocomial pathogens, as well as one of the main causes of chronic respiratory infections in patients with underlying diseases such as cystic fibrosis or chronic obstructive pulmonary disease. The high intrinsic antibiotic resistance of this pathogen, together with its extraordinary capacity for acquiring additional resistances through chromosomal mutations, determines a major threat for antimicrobial therapy in hospitals worldwide. Even more concerning is the increasing detection of multiple antimicrobial resistance determinants in this microorganism, frequently located on integrons, acquired by horizontal transfer through plasmids and/or transposons. Among these mechanisms, the carbapenemases are particularly relevant, due to the wide spectrum of antibiotics affected. This work reviews the epidemiology, impact, and detection of the carbapenemases described so far in the Pseudomonas spp., that mainly include class B enzymes (metallo-β-lactamases [MBL]: IMP, VIM, SPM, GIM, AIM, or DIM), but also, to a lower extent, class A (GES y KPC) and D (OXA) beta-lactamases. The presence of transferable carbapenemases is not only important in P. aeruginosa, but also in other less clinically-relevant species of the genus, since they can act as reservoires and dispersion vectors of these resistance determinants. The growing prevalence of carbapenemase-producing clinical isolates calls for the implementation of multidisciplinary strategies to optimize the detection and minimize the dissemination of these multidrug resistant strains and the involved transferable genetic elements. 相似文献
63.
Carlos A.R. Véo Sarhan S. SaadSérgio M. Nicolau Armando G.F. MelaniMarcos V.A. Denadai 《European journal of obstetrics, gynecology, and reproductive biology》2008
Objective
The objective was to evaluate the prevalence of human papillomavirus (HPV) in the anal canal of women with cervical intraepithelial neoplasia (CIN) grade III.Study design
Two groups were compared. In group I (study group), 40 women who had undergone cervical biopsy with a histopathological result indicating CIN III were evaluated. Group II (control) consisted of 40 women with normal results from colposcopic examination and colpocytological tests. The women in group I who presented high-grade neoplasia in colpocytological tests underwent collection of material from the uterine cervix and anal canal for investigating HPV DNA using the Hybrid Capture II® technique. Colposcopy and cervical biopsy were then performed. If CIN III was confirmed, HPV DNA was investigated in the material collected. In group II, colpocytological tests and colposcopy were performed and, if normal, the procedure was similar to that followed for group I, except that no biopsy was performed.Results
In group I, 39 women (97.5%) were positive for HPV in the uterine cervix and 14 women (35%) in the anal canal. In group II, only four women (10%) had a positive HPV test, for both the uterine cervix and the anal canal.Conclusions
The prevalence of HPV in the anal canal of the women with CIN III was greater than in the women without CIN III. 相似文献64.
Ohne Zusammenfassung 相似文献
65.
Determination of N-acetylneuraminic acid concentration in the attached gingival tissue of rats related to the age and sex of the animals was carried out. The concentration of the sialic acid decreased with increasing age. Differences between male and female animals were noted. 相似文献
66.
CJ Mitchell P Stephany 《Malawi medical journal : the journal of Medical Association of Malawi》2013,25(3):88-89
An outbreak of Tunga Penetrans (Jigger Flea) infestation affecting a number of villages near to a Central Hospital in Malawi is described. Due to the large number of affected individuals, high parasitic load, and extended duration of infection an alternative to the recommended approach of surgical removal of the flea was required. Benzyl benzoate paint and liquid paraffin had been used in local Primary Healthcare settings previously and topical treatment with antiparasitic agents has been advocated in the literature, particularly for severe infestation. Benzyl benzoate and liquid paraffin were applied topically to four adults with numerous jigger flea burrows, and their progress assessed regularly. After completion of 7 days of treatment patients noted that fleas were dislodging spontaneously, and that embedded parasites had not increased in size to the same extent that untreated fleas had in previous infestations. Following confirmation of the viability of its implementation in a resource-poor setting, this treatment regimen has subsequently been adopted by the local branch of the District Health Office for distribution to infected communities. 相似文献
67.
NU Jerath JS Newman & CJ Boes 《Cephalalgia : an international journal of headache》2009,29(10):1028-1033
The aim of this study was to review the life of Mary E. O'Sullivan and to summarize her important contributions to the study of migraine. Mary E. O'Sullivan underwent extensive training to become a neurologist at a time when only 5% of women in America were physicians. She published five papers on migraine. In a 1936 Journal of the American Medical Association article, she described a patient with ergotamine overuse headache and recommended that daily doses of oral ergotamine should be avoided. Three years later she described migraine as a 'complex' syndrome with multiple causes and multiple cures. Mary E. O'Sullivan, an ambitious female headache specialist of the 1930s, was an early advocate of the use of ergotamine to treat migraine, yet she was one of the first to report ergotamine overuse headache. Although her life was short, her research, knowledge and ambition at a time when women had limited opportunities in medicine have left a mark. 相似文献
68.
29名1型糖尿病妇女在妊娠期间接受持续皮下胰岛素输注(CSII)作为胰岛素强化治疗(其中27名妇女在计划妊娠时开始治疗,2名在怀孕第1个月开始接受治疗),另外29名孕妇接受每日多次胰岛素注射(MDI)治疗。两组人群在年龄、糖尿病病程、White分级、孕前的BMI、孕前已产子女数和HbA1c方面互相匹配。对孕妇的代谢控制情况和急性并发症包括酮症酸中毒、严重低血糖发作、妊娠高血压的发展以及先兆子痫的发作进行登记, 相似文献
69.
Nikolai Kuhnert Adam Le‐Gresley Daniel C. Nicolau Ana Lopez‐Periago 《Journal of labelled compounds & radiopharmaceuticals》2007,50(13):1215-1223
The synthesis and self‐association of chiral isotopically labeled trianglamine macrocycles under electrospray mass spectrometer conditions in an ion trap are described. A moderate diastereoselectivity in the self‐association process was observed providing a synthetic model system for the investigation of chiral self‐association in the gas phase. The first non‐covalently bound dimer exclusively bonded through aromatic–aromatic interactions was observed in the gas phase. Evidence for self‐association in solution was observed by diffusion nuclear magnetic resonance spectroscopy. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
70.