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Episodic memory is defined as the ability to recall events in a spatiotemporal context. Formation of such memories is critically dependent on the hippocampal formation and its inputs from the entorhinal cortex. To be able to support the formation of episodic memories, entorhinal cortex and hippocampal formation should contain a neuronal code that follows several requirements. First, the code should include information about position of the agent (“where”), sequence of events (“when”), and the content of the experience itself (“what”). Second, the code should arise instantly thereby being able to support memory formation of one‐shot experiences. For successful encoding and to avoid interference between memories during recall, variations in location, time, or in content of experience should result in unique ensemble activity. Finally, the code should capture several different resolutions of experience so that the necessary details relevant for future memory‐based predictions will be stored. We review how neuronal codes in entorhinal cortex and hippocampus follow these requirements and argue that during formation of episodic memories entorhinal cortex provides hippocampus with instant information about ongoing experience. Such information originates from (a) spatially modulated neurons in medial entorhinal cortex, including grid cells, which provide a stable and universal positional metric of the environment; (b) a continuously varying signal in lateral entorhinal cortex providing a code for the temporal progression of events; and (c) entorhinal neurons coding the content of experiences exemplified by object‐coding and odor‐selective neurons. During formation of episodic memories, information from these systems are thought to be encoded as unique sequential ensemble activity in hippocampus, thereby encoding associations between the content of an event and its spatial and temporal contexts. Upon exposure to parts of the encoded stimuli, activity in these ensembles can be reinstated, leading to reactivation of the encoded activity pattern and memory recollection. 相似文献
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Suzanne M. Gillespie Andrea L. Moser Murthy Gokula Thomas Edmondson Joseph Rees Dallas Nelson Steven M. Handler 《Journal of the American Medical Directors Association》2019,20(2):115-122
Objectives
This document offers guidance to clinicians and facilities on the use of telemedicine to deliver medically necessary evaluation and management of change of condition for nursing home residents.Settings and participants
Members of the telemedicine workgroup of AMDA—The Society for Post-Acute Long-Term Medicine-developed this guideline through both telephonic and face-to-face meetings between April 2017 and September 2018. The guideline is based on the currently available research, experience, and expertise of the workgroup's members, including a summary of a recently completed systematic mixed studies literature review to determine evidence for telemedicine to reduce emergency department visits or hospitalizations of nursing home residents.Results
Research and experience to date support the use of telemedicine as a tool in change of condition assessment and management as a means of reducing unnecessary emergency department visits and hospitalization. Telemedicine-delivered care should be integrated into the primary care of the resident and delivered by providers with competency in post-acute long-term care. The development and sustainability of telemedicine programs is heavily dependent on financial implications. Quality measures should be defined for telemedicine programs in nursing homes.Conclusions/Implications
Telemedicine programs in nursing homes can contribute to the delivery of timely, high quality medical care, which reduces unnecessary hospitalization. Reimbursement for telemedicine-driven care should be based upon medical necessity of visits to care and the maintenance of quality standards. More studies are needed to understand which telemedicine tools and processes are most effective in improving outcomes for nursing home residents. 相似文献5.
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A reliable experimental determination of the partition coefficient Pow of organic pigments is met with serious difficulties due to the extremely low water solubilities of these compounds. Therefore, the Pow values and the water solubilities were calculated for 11 typical organic pigments and some disperse dyes as well. The calculated Pow values of the pigments were very high predicting bioaccumulation factors (BF) several orders of magnitude above 100. Based on recent studies confirming that n-octanol simulates lipids in their solubilizing effect on organic chemicals, the solubilities of these organic pigments in n-octanol were measured in order to estimate their potential for lipid storage. The very low solubility values indicate that in spite of the very high predicted BF such pigments cannot build up concentrations in lipids (hence in fish) which could be of concern considering their generally low toxicity and the extremely small amounts entering the environment. Therefore, there should be no need to perform a fish bioaccumulation test for assessing the bioaccumulation potential of such compounds, provided they show comparable solubility characteristics as the pigments investigated in this study. 相似文献
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E Moser 《Der Radiologe》1989,29(3):103-108
The progress made in ultrasonography and improved in vitro tests have changed the field of application for scintigraphy of the thyroid. Thyroid scanning itself has been improved by the use of isotopes with better imaging properties and less radiation burden (99mTc, 123I) and by gamma cameras for imaging. Scintigraphy yields real topographic and functional information on the gland, in addition to which ultrasonography gives morphological data only. This holds true especially for autonomous nodular goiter with iodine deficiency. The goal of thyroid imaging is always to match the appropriate diagnostic procedure with all the clinical data available. When optimized techniques (gamma camera, on-line processor) are used thyroid scintigraphy is useful for the diagnosis, adequate therapy and follow-up of various thyroid disorders. 相似文献
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In the first 100 patients operated on for C T-E PH, three were referred with the diagnosis of UPAA having been made elsewhere. We found that many features of these two conditions are so similar that differential diagnosis is very difficult. Shared features may include findings on chest x-ray film, pulmonary angiography, CT scan and MRI studies. Since the two conditions vary substantially with respect to the methods of potential surgical correction, recognition of this possible differential diagnostic dilemma is important. 相似文献