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21.
Blain J Townsend E 《Canadian journal of occupational therapy. Revue canadienne d'ergothérapie》1993,60(5):271-285
The Guidelines Impact Study investigated use and usefulness of the guidelines for client-centred practice produced in the 1980's by the Department of National Health and Welfare and the Canadian Association of Occupational Therapists. This paper outlines the study, summarizes findings, and discusses implications for revising and updating the Guidelines. Qualitative interview data from key informants across Canada were incorporated into a quantitative survey of a 5% sample of CAOT members. Data reveal variable use of the Guidelines, with greatest use in acute care and rehabilitation services; and mixed interpretations of the Model of Occupational Performance, particularly 'environment' and 'spiritual component'. Recommendations include: clarification of the purpose and audience of revised Guidelines; national consultation during updating to include diverse forms of practice; and rethinking the Model of Occupational Performance as a dynamic model. Updated Guidelines should include both generic concepts and specific applications for different types of occupational therapy practice. 相似文献
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Pouly S Becher B Blain M Antel JP 《Journal of neuropathology and experimental neurology》2000,59(4):280-286
Interferon gamma (IFN-gamma) has been shown to be produced within multiple sclerosis (MS) lesions by infiltrating lymphocytes; systemic administration of this cytokine induces exacerbation of the disease. The aim of the current study was to establish the contribution of IFN-gamma to oligodendrocyte (OL) injury. Our studies utilized cultured human OLs, obtained by dissociation of surgically derived non-MS adult brain tissue. Neither cell survival nor myelin basic protein (MBP) gene expression were affected after 96 hours of treatment with IFN-gamma (100 U/ml), as assessed by LDH release, nucleosome enrichment assay, and RT-PCR. Expression of the death receptor Fas (CD95, APO-1) was, however, significantly increased. Furthermore, IFN-gamma-treated OLs became susceptible to Fas-mediated apoptosis when compared with untreated cells, and were protected by pretreatment with the caspase inhibitor ZVAD. TNF-alpha augmented the IFN-gamma-induced effect. Our results thus indicate that IFN-gamma is not directly cytotoxic for human OLs in culture, but could indirectly modulate functional injury-related responses by upregulating Fas on the cell surface. 相似文献
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WG Mitchell H Lynn JF Bale MA Maeder SM Donfield B Garg AH Tilton JK Willis TP Bohan 《Pediatrics》1997,100(5):817-824
BACKGROUND: Boys and young men with hemophilia treated with factor infusions before 1985 had a substantial risk of acquiring the human immunodeficiency virus (HIV) and the acquired immunodeficiency syndrome. This study was designed to assess the effects of HIV and hemophilia per se on neurological function in a large cohort of subjects with hemophilia, and to investigate the relationships between neurological disease and death during follow-up. METHODS: Three hundred thirty-three boys and young men (207 HIV seropositive and 126 HIV seronegative) were evaluated longitudinally in a multicenter, multidisciplinary study. Neurological history and examination were conducted at baseline and annually for 4 years. The relationship between neurological variables, HIV serostatus, CD4+ cell counts, and vital status at the conclusion of the study was examined using logistic regression models. RESULTS: The risks of nonhemophilia-associated muscle atrophy, behavior change, and gait disturbance increased with time in immune compromised HIV-seropositive subjects compared with HIV seronegative or immunologically stable HIV-seropositive subjects. The risk of behavior change in immune compromised HIV-seropositive hemophiliacs, for example, rose to 60% by year 4 versus 10% to 17% for the other study groups. Forty-five subjects (13.5%), all of whom were HIV seropositive, died by year 4. Subjects who died had had increased risks of hyperreflexia, nonhemophilia-associated muscle atrophy, and behavior change. CONCLUSIONS: These results indicate that immune compromised, HIV-seropositive hemophiliacs have high rates of neurological abnormalities over time and that neurological abnormalities were common among subjects who later died. By contrast, immunologically stable HIV-seropositive subjects did not differ from the HIV-seronegative participants. Hemophilia per se was associated with progressive abnormalities of gait, coordination, and motor function. 相似文献
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Dermoid tumours in children usually occur in two locations: at the anterior fontanelle and on the occipital squama. An exceptional site of origin for a posterior fossa dermoid cyst is the extradural space. There are only six previous cases of this situation reported in the literature. A series of 103 subscalp and calvarial masses in children were reviewed and three children are reported with extradural dermoids of the posterior fossa, which communicated with the skin through midline occipital dermal sinuses. All three children were seen after the rapid growth or the formation of an abscess in a previously noted occipital subcutaneous mass present since birth. Although computed tomography or magnetic resonance imaging showed the dermal sinus and the intracranial tumour, these studies were unable to ascertain the intradural or extradural nature of the tumours, their exact origin only being established at operation. Histopathological study showed preclinical signs of infection in the two patients that had not yet formed an abscess. It is suggested that early neurosurgical treatment of these neoplasms should be done to prevent the development of severe intracranial infection. The previously reported simplicity of surgical removal of occipital extradural dermoids was not confirmed in this series. 相似文献
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Laura M. Carlson Michelle Angrish Avanti V. Shirke Elizabeth G. Radke Brittany Schulz Andrew Kraft Richard Judson Grace Patlewicz Robyn Blain Cynthia Lin Nicole Vetter Courtney Lemeris Pamela Hartman Heidi Hubbard Xabier Arzuaga Allen Davis Laura V. Dishaw Ingrid L. Druwe Hillary Hollinger Ryan Jones J. Phillip Kaiser Lucina Lizarraga Pamela D. Noyes Michele Taylor Andrew J. Shapiro Antony J. Williams Kristina A. Thayer 《Environmental health perspectives》2022,130(5)
Background: Per- and polyfluoroalkyl substances (PFAS) are a large class of synthetic (man-made) chemicals widely used in consumer products and industrial processes. Thousands of distinct PFAS exist in commerce. The 2019 U.S. Environmental Protection Agency (U.S. EPA) Per- and Polyfluoroalkyl Substances (PFAS) Action Plan outlines a multiprogram national research plan to address the challenge of PFAS. One component of this strategy involves the use of systematic evidence map (SEM) approaches to characterize the evidence base for hundreds of PFAS.Objective: SEM methods were used to summarize available epidemiological and animal bioassay evidence for a set of PFAS that were prioritized in 2019 by the U.S. EPA’s Center for Computational Toxicology and Exposure (CCTE) for in vitro toxicity and toxicokinetic assay testing.Methods: Systematic review methods were used to identify and screen literature using manual review and machine-learning software. The Populations, Exposures, Comparators, and Outcomes (PECO) criteria were kept broad to identify mammalian animal bioassay and epidemiological studies that could inform human hazard identification. A variety of supplemental content was also tracked, including information on in vitro model systems; exposure measurement–only studies in humans; and absorption, distribution, metabolism, and excretion (ADME). Animal bioassay and epidemiology studies meeting PECO criteria were summarized with respect to study design, and health system(s) were assessed. Because animal bioassay studies with exposure duration (or reproductive/developmental study design) were most useful to CCTE analyses, these studies underwent study evaluation and detailed data extraction. All data extraction is publicly available online as interactive visuals with downloadable metadata.Results: More than 40,000 studies were identified from scientific databases. Screening processes identified 44 animal and 148 epidemiology studies from the peer-reviewed literature and 95 animal and 50 epidemiology studies from gray literature that met PECO criteria. Epidemiological evidence (available for 15 PFAS) mostly assessed the reproductive, endocrine, developmental, metabolic, cardiovascular, and immune systems. Animal evidence (available for 40 PFAS) commonly assessed effects in the reproductive, developmental, urinary, immunological, and hepatic systems. Overall, 45 PFAS had evidence across animal and epidemiology data streams.Discussion: Many of the PFAS were data poor. Epidemiological and animal evidence were lacking for most of the PFAS included in our search. By disseminating this information, we hope to facilitate additional assessment work by providing the initial scoping literature survey and identifying key research needs. Future research on data-poor PFAS will help support a more complete understanding of the potential health effects from PFAS exposures. https://doi.org/10.1289/EHP10343 相似文献
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