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Expression of von Hippel-Lindau tumor suppressor and tumor-associated carbonic anhydrases Ⅸ and Ⅻ in normal and neoplastic colorectal mucosa 总被引:1,自引:0,他引:1
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HCV selection and HVR1 evolution in a chimpanzee chronically infected with HCV-1 over 12 years. 总被引:1,自引:0,他引:1
Ling Lu Nakano Tatsunori Chunhua Li Sana Waheed Fengxiang Gao Betty H Robertson 《Hepatology research》2008,38(7):704-716
Aim: To study hepatitis C virus (HCV) selection and hypervariable region-1 (HVR1) evolution in a chimpanzee chronically infected with HCV-1 over 12 years after inoculation with a human factor VIII concentrate contaminated with HCV. Methods: From the inoculum, the earliest chimpanzee plasma and 12 annual plasma samples, HCV fragments including HVR1 were amplified followed by cloning and sequencing. Results: Five HCV subtypes - 1a, 1b, 2a, 2b, 3a - and multiple 1a strains were identified in the inoculum. Two 1a strains were found in the earliest chimpanzee sample, while a single HCV-1 strain was detected in the 12 annual samples. None of the chimpanzee sequences were identical to those found in the inoculum. Over 12 years, HVR1 patterns changed irregularly, but a few patterns showed identical nucleotide or amino acid sequences. In the last three years, the variety of HVR1 patterns decreased, while the proportion of major patterns increased. These corresponded to a higher virus load and a lower number of amino acid substitutions. Simultaneously, the HVR1 sequences became more similar to the consensus sequence of the 1a subtype. Conclusion: HCV selection was observed from the inoculum to the inoculated chimpanzee and from the early acute hepatitis to the persistent chronic infection. The selection occurred at three levels: among subtypes after transmission, among isolates during acute hepatitis and among quasispecies in chronic infection. 相似文献
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Jonathan Hammond Katja Gravenhorst Emma Funnell Susan Beatty Derek Hibbert Jonathan Lamb Heather Burroughs Marija Kovand?i? Mark Gabbay Christopher Dowrick Linda Gask Waquas Waheed Carolyn A Chew-Graham 《The British journal of general practice》2013,63(608):e177-e184
Background
General practice receptionists fulfil an essential role in UK primary care, shaping patient access to health professionals. They are often portrayed as powerful ‘gatekeepers’. Existing literature and management initiatives advocate more training to improve their performance and, consequently, the patient experience.Aim
To explore the complexity of the role of general practice receptionists by considering the wider practice context in which they work.Design and setting
Ethnographic observation in seven urban general practices in the north-west of England.Method
Seven researchers conducted 200 hours of ethnographic observation, predominantly in the reception areas of each practice. Forty-five receptionists were involved in the study and were asked about their work as they carried out their activities. Observational notes were taken. Analysis involved ascribing codes to incidents considered relevant to the role and organising these into related clusters.Results
Receptionists were faced with the difficult task of prioritising patients, despite having little time, information, and training. They felt responsible for protecting those patients who were most vulnerable, however this was sometimes made difficult by protocols set by the GPs and by patients trying to ‘play’ the system.Conclusion
Framing the receptionist–patient encounter as one between the ‘powerful’ and the ‘vulnerable’ gets in the way of fully understanding the complex tasks receptionists perform and the contradictions that are inherent in their role. Calls for more training, without reflective attention to practice dynamics, risk failing to address systemic problems, portraying them instead as individual failings. 相似文献17.
Julia Schottenhamml Eric M. Moult Stefan B. Ploner Siyu Chen Eduardo Novais Lennart Husvogt Jay S. Duker Nadia K. Waheed James G. Fujimoto Andreas K. Maier 《Biomedical optics express》2021,12(1):84
In this paper we present a fully automated graph-based segmentation algorithm that jointly uses optical coherence tomography (OCT) and OCT angiography (OCTA) data to segment Bruch’s membrane (BM). This is especially valuable in cases where the spatial correlation between BM, which is usually not visible on OCT scans, and the retinal pigment epithelium (RPE), which is often used as a surrogate for segmenting BM, is distorted by pathology. We validated the performance of our proposed algorithm against manual segmentation in a total of 18 eyes from healthy controls and patients with diabetic retinopathy (DR), non-exudative age-related macular degeneration (AMD) (early/intermediate AMD, nascent geographic atrophy (nGA) and drusen-associated geographic atrophy (DAGA) and geographic atrophy (GA)), and choroidal neovascularization (CNV) with a mean absolute error of ∼0.91 pixel (∼4.1 μm). This paper suggests that OCT-OCTA segmentation may be a useful framework to complement the growing usage of OCTA in ophthalmic research and clinical communities. 相似文献
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Michael Olamoyegun Waheed Ibraheem Sandra Iwuala Morenike Audu Babatope Kolawole 《African health sciences》2015,15(4):1136-1141