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61.
LTC Edwin S. Beatrice MC Georg D. Frisch MBA 《Archives of environmental & occupational health》2013,68(5):322-326
The eyes of rhesus monkeys were exposed to argon (514.5 nm) and ruby (694.3 nm) laser irradiation using various retinal image diameters which were estimated by microphotometric techniques. The experimental design for both wavelengths produced image diameters of 40μ to 50μ for the “minimal” case and approximately 500μ to 1,000μ for the larger irradiance series employed. Extramacular retinal exposure sites were examined by ophthalmoscopic and histopathological techniques. Flat preparations of the pigmented epithelium and sensory layers of the retina were utilized in the confirmation of damage at low power levels. All data were statistically analyzed to establish trends, and results were compared for the wavelengths employed. Results indicate that retinal damage is primarily dependent on energy distribution as a function of image diameter and exposure duration. 相似文献
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Myeloproliferative syndrome induced by MPSV in DBA/2 mice: presence of a mixed-colonies promoting activity (MPA) in the spleen 总被引:1,自引:0,他引:1
Le Bousse-Kerdiles MC; Smadja-Joffe F; Klein B; Jasmin C; Comisso M; Ostertag W 《Blood》1983,61(3):520-524
The myeloproliferative syndrome induced by the myeloproliferative sarcoma virus (MPSV) in DBA/2 mice stimulates the proliferation of pluripotent hemopoietic stem cells (HSC) and of progenitors committed toward granulomacrophagic and erythroid cell lines. This stimulation may result from a direct effect of the MPSV on HSC or from an indirect effect via locally secreted factors. Normal isogenic bone marrow cells were incubated in the mixed colony-forming unit system in semisolid medium supplemented with conditioned media obtained after incubating neoplastic spleen cells for 3 days at 37 degrees C. These spleen conditioned media contain an activity that is physically separable from MPSV by ultracentrifugation and which, in the presence of a very low quantity of erythropoietin, can induce in vitro the proliferation and differentiation of pluripotent HSC, detected by this Mix-CFU technique. We termed this activity mixed-colonies promoting activity (MPA). These results suggest that the hyperplasia of the nonlymphoid hematopoietic system in the neoplastic spleen results from an indirect effect of the MPSV on pluripotent HSC via locally secreted factors. 相似文献
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Karl Pillemer Emily K. Chen Catherine Riffin Holly Prigerson MC Reid Leslie Schultz 《American journal of public health》2015,105(11):2237-2244
We employed the research-to-practice consensus workshop (RTP; workshops held in
New York City and Tompkins County, New York, in 2013) model to merge researcher
and practitioner views of translational research priorities in palliative care.
In the RTP approach, a diverse group of frontline providers generates a research
agenda for palliative care in collaboration with researchers. We have presented
the major workshop recommendations and contrasted the practice-based research
priorities with those of previous consensus efforts. We uncovered notable
differences and found that the RTP model can produce unique insights into
research priorities. Integrating practitioner-identified needs into research
priorities for palliative care can contribute to addressing palliative care more
effectively as a public health issue.Over the past 2 decades, palliative care has become established as a promising approach
for addressing the needs of individuals with life-threatening illnesses from a holistic,
interdisciplinary perspective. For this project, we defined palliative care as an
approach that improves the quality of life of patients and families facing the problems
encountered in life-threatening illness by preventing and relieving suffering. Core
components of palliative care include providing relief from pain and other distressing
symptoms, affirming dying as a normal process, integrating psychological and spiritual
aspects of care, enhancing the quality of life of patients, and offering support systems
to patients and their families to help them live as fully as possible until death
occurs.Research suggests that palliative care results in positive patient outcomes, greater
patient and family satisfaction, and significant cost savings.1,2 The American Public Health Association, the
World Health Organization, and the Institute of Medicine3–6 have identified the
development of a robust palliative care delivery system as a key public health issue
because of the documented ability of palliative care to deliver effective and efficient
patient- and symptom-focused care to a growing population in need.In its 2013 report the American Public Health Association specifically detailed the
public health implications of palliative care, acknowledged the growing burden of
advanced chronic illness and disease in older adults, and recommended key steps to
address the problem. This policy statement called for federal, state, and local efforts
to promote effective symptom management in populations with serious illness or at the
end of life. Other recommended initiatives included the development of a palliative care
workforce, educational programs to improve uptake and use of palliative and hospice
care, and research funding to support the expansion of palliative care initiatives.
Achieving these goals will require moving beyond traditional medical practices to
include both policies and initiatives at the public health level.Despite the potential of palliative care to address the mental and physical health needs
of individuals with advanced illness, significant knowledge gaps impede its reach and
effectiveness. Reports from scientific bodies and consensus workshops have highlighted
weaknesses in the literature and called for more research on palliative care and
improved research methods.7–10 Thus, although both interest in and demand for
palliative care are increasing, reviews of the knowledge base continue to lament the
lack of research on many key issues.11,12Especially urgent is a research agenda that fits most closely with the needs of providers
who deliver palliative care. The systematic engagement of community practitioners in a
consensus process can lead to particularly useful and actionable recommendations for
research,13–15 which are greatly needed at this stage in the
development of the field. Therefore, to shed new light on research priorities in
palliative care, we used a structured, participatory method designed to solicit
practitioner input on research priorities: the research-to-practice consensus workshop
(RTP) model.16We employed the RTP approach to identify knowledge gaps and types of studies that should
be conducted to improve providers’ ability to deliver palliative care most
effectively. This model harnesses practice wisdom by engaging clinicians, agency staff,
and other practitioners with researchers in a process of articulating and refining
research questions and research priorities that honors scientific expertise and practice
wisdom. 相似文献
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Kathryn M. Day Rachel Pike Trevor G. Winstanley Clare Lanyon Stephen P. Cummings Muhammad W. Raza Neil Woodford John D. Perry 《Journal of clinical microbiology》2013,51(6):1881-1886
The aim of this study was to determine the ability of a disc susceptibility test using faropenem (10 μg) to predict carbapenemase activity in Enterobacteriaceae. A collection of 166 isolates of carbapenemase-producing Enterobacteriaceae (CPE) and 82 isolates of Enterobacteriaceae that produced other β-lactamases was compiled from diverse sources. Disc susceptibility testing was performed using the CLSI/EUCAST methodology with discs of faropenem (10 μg), temocillin (30 μg), and four carbapenems (each 10 μg). A further prospective evaluation of the faropenem disc susceptibility test was performed using 205 consecutive isolates referred to a United Kingdom reference laboratory in parallel with molecular methods for carbapenemase detection. Of 166 isolates of CPE, 99% showed growth up to the edge of a 10-μg faropenem disc compared with only 6% of other β-lactamase producers (sensitivity, 99%; specificity, 94%). A “double zone” around 10-μg faropenem discs was frequently associated with OXA-48 producers. Of the carbapenems, the most useful agent was imipenem, where a zone diameter of ≤23 mm as a predictor of carbapenemase activity had a sensitivity of 99% and a specificity of 85%. The presence of no zone of inhibition around a 30-μg temocillin disc was a consistent feature of strains producing OXA-48 carbapenemase. For 205 isolates of Enterobacteriaceae referred to a United Kingdom reference laboratory, growth up to a 10-μg faropenem disc correctly identified 84 of 86 carbapenemase producers (98% sensitivity), with a specificity of 87%. Disc susceptibility testing using faropenem (10 μg) is a simple, convenient, and highly predictive screening test for carbapenemase-producing Enterobacteriaceae. 相似文献
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