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Transgender (trans) women experience barriers to access to HIV care, which result in their lower engagement in HIV prevention, treatment and support relative to cisgender people living with HIV. Studies of trans women's barriers to HIV care have predominantly focused on perspectives of trans women, while barriers are most often described at provider, organisation and/or systems levels. Comparing perspectives of trans women and service providers may promote a shared vision for achieving health equity. Thus, this qualitative study utilised focus groups and semi-structured interviews conducted 2018–2019 to understand barriers and facilitators to HIV care from the perspectives of trans women (n = 26) and service providers (n = 10). Barriers endorsed by both groups included: (a) anticipated and enacted stigma and discrimination in the provision of direct care, (b) lack of provider knowledge of HIV care needs for trans women, (c) absence of trans-specific services/organisations and (d) cisnormativity in sexual healthcare. Facilitators included: (a) provision of trans-positive trauma-informed care, (b) autonomy and choice for trans women in selecting sexual health services and (c) models for trans-affirming systems change. Each theme had significant overlap, yet nuanced perspective, between trans women and service providers. Specific recommendations to improve HIV care access for trans women are discussed. These recommendations can be used by administrators and service providers alike to work collaboratively with trans women to reduce barriers and facilitators to HIV care and ultimately to achieve health equity for trans women.  相似文献   
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Proteoglycans and glycosaminoglycans are the main components of the extracellular matrix of the nucleus pulposus. Intervertebral disc degeneration due to aging and excessive mechanical loads results in adverse quantitative and structural changes to the macromolecules. Metalloproteinases induced by inflammatory mediators play a key role in degrading proteoglycans. Progressive matrix breakdown decreases water content in the disc. Dehydration compromises disc cells function and impairs resistance to compression. Biochemical changes may result in disc prolapse. Modifying the metabolism of proteoglycans and glycosaminoglycans might be an effective therapeutic strategy.  相似文献   
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Evaluation of brain tumor metabolism with [11C]choline PET and 1H-MRS   总被引:6,自引:0,他引:6  
Background: The signal of choline containing compounds (Cho) in proton magnetic resonance spectroscopy (1H-MRS) is elevated in brain tumors. [11C]choline uptake as assessed using positron emission tomography (PET) has also been suggested to be higher in brain tumors than in the normal brain. We examined whether quantitative analysis of choline accumulation and content using these two novel techniques would be helpful in non-invasive, preoperative evaluation of suspected brain tumors and tumor malignancy grade. Methods: 12 patients with suspected brain tumor were studied using [11C]choline PET, gadolinium enhanced 3-D magnetic resonance imaging and 1H-MRS prior to diagnostic biopsy or resection. Eleven normal subjects served as control subjects for 1H-MRS. Results: The concentrations of Cho and myoinositol (mI) were higher and the concentration of N-acetyl signal/group (NA) lower in brain tumors than in the corresponding regions of the normal brain. There were no significant differences in metabolite concentrations between low- and high-grade gliomas. In non-tumorous lesions Cho concentrations were lower and NA concentrations higher than in any of the gliomas. Enormously increased lipid peak differentiated lymphomas from all other lesions. The uptake of [11C]choline at PET did not differ between low- and high-grade gliomas. The association between Cho concentration determined in 1H-MRS and [11C]choline uptake measured with PET was not significant. Conclusion: Both 1H-MRS and [11C]choline PET can be used to estimate proliferative activity of human brain tumors. These methods seem to be helpful in differential diagnosis between lymphomas, non-tumorous lesions and gliomas but are not superior to histopathological methods in estimation of tumor malignancy grade.  相似文献   
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Purpose: To quantify the cerebrospinal fluid (CSF) dynamics in the aqueduct of children with normal and dilated ventricles using MR phase-contrast technique.Material and Methods: Eighteen patients (6 months to 17 years of age) with various neurological symptoms underwent routine brain MR imaging and CSF flow measurement in the aqueduct. Nine patients had normal ventricles, 5 had dilated ventricles and 4 had a ventriculoperitoneal shunt.Results: The CSF velocity and flow rates in the aqueduct in patients with normal and dilated ventricles showed marked inter-individual variation and clear overlap. In a patient with tight aqueductal stenosis and increased ventricular pressure, pronounced CSF flow in the aqueduct was measured. Absence of flow in another patient with aqueductal stenosis was detected. Measurable although low flow in the aqueduct in 4 patients with a ventriculoperitoneal shunt was found.Conclusion: Quantitative phase MR flow measurement in the aqueduct demonstrated aqueductal stenosis; these patients had either pronounced flow or no flow in the aqueduct.  相似文献   
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BACKGROUND: Eye fundus destruction and type II muscle fiber atrophy in gyrate atrophy of the choroid and retina with hyperornithinaemia (GA) may be mediated by elevated ornithine concentrations which strongly inhibit creatine biosynthesis. This results in deficiency of creatine phosphate (PCr), a key intracellular energy source, as we have demonstrated in skeletal muscle of the patients by 31P magnetic resonance spectroscopy (31P MRS). MATERIALS AND METHODS: Possible correction of the relative PCr deficiency by long-term daily exogenous supplementation of creatine or its precursors was investigated in four GA patients receiving creatine and in five patients treated with guanidinoacetic acid-methionine combination. The relative PCr concentration, expressed as PCr/Pi (Pi; inorganic phosphate) or as PCr/ATP ratios, was compared with the values of untreated GA patients, and matched healthy volunteers. RESULTS: Muscle PCr/Pi ratios (mean +/- SD) of the untreated and creatine supplemented GA patients and controls were 4.9 +/- 1.4, 7.9 +/- 0.4 and 8.4 +/- 1.3. Guanidinoacetate-methionine combination was similarly effective (respective PCr/Pi ratios: 4.9 +/- 0.7, 6.3 +/- 1.1 and 10.7 +/- 2.8). CONCLUSION: Supplementation with creatine or creatine precursors almost normalised low muscle PCr/Pi ratios of patients with GA.  相似文献   
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AIM: To study milk consumption and subjective milk- related symptoms in adults genotyped for adult-type hypolactasia. METHODS: A total of 1900 Finnish adults were genotyped for the C/T-13910 variant of adult-type hypolactasia and filled in a structured questionnaire concerning milk consumption and gastrointestinal problems. RESULTS: The C/C-13910 genotype of adult-type hypolactasia was present in 18% of the study population. The prevalence of the C/C-13910 genotype was higher among subjects who were undergoing investigations because of abdominal symptoms (24%, P < 0.05). Those with the C/C-13910 genotype drank less milk than subjects with either the C/T-13910 or the T/T-13910 genotype of lactase persistence (18% vs 38%; 18% vs 36%, P < 0.01). Subjects with the C/C-13910 genotype had experienced more gastrointestinal symptoms (84%) during the preceding three-month period than those with the C/T-13910 (79%, P < 0.05) or the T/T-13910 genotype (78 %, P < 0.05). Only 9% (29/338) of the subjects with the C/C-13910 genotype consumed milk and reported no symptoms from it.CONCLUSION: Gastrointestinal symptoms are more common among adults with the C/C-13910 genotype of adult-type hypolactasia than in those with genotypes of lactase persistence.  相似文献   
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