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991.

Background:

Characterizing high-cost users of health care resources is essential for the development of appropriate interventions to improve the management of these patients. We sought to determine the concentration of health care spending, characterize demographic characteristics and clinical diagnoses of high-cost users and examine the consistency of their health care consumption over time.

Methods:

We conducted a retrospective analysis of all residents of Ontario, Canada, who were eligible for publicly funded health care between 2009 and 2011. We estimated the total attributable government health care spending for every individual in all health care sectors.

Results:

More than $30 billion in annual health expenditures, representing 75% of total government health care spending, was attributed to individual costs. One-third of high-cost users (individuals with the highest 5% of costs) in 2009 remained in this category in the subsequent 2 years. Most spending among high-cost users was for institutional care, in contrast to lower-cost users, among whom spending was predominantly for ambulatory care services. Costs were far more concentrated among children than among older adults. The most common reasons for hospital admissions among high-cost users were chronic diseases, infections, acute events and palliative care.

Interpretation:

Although high health care costs were concentrated in a small minority of the population, these related to a diverse set of patient health care needs and were incurred in a wide array of health care settings. Improving the sustainability of the health care system through better management of high-cost users will require different tactics for different high-cost populations.Health care spending per person in any given year is highly uneven. The concentration of health care utilization among small numbers of patients is well established. In the United States, the Agency for Healthcare Research and Quality reported that 1% of users in 2008 accounted for 20% of expenditures and that 5% of users accounted for nearly 50% of expenditures.1 Data from Canada in 1972 and 1996, and again in 2009, showed that high-cost users (individuals with the highest 5% of costs) consumed 65% of combined hospital and nursing home costs, 64% of acute care days and 84% of combined acute and post-acute home care resources, respectively.24Each year, a few people have major health events that must be addressed, often with expensive treatments. The relative rarity and unpredictability of these events for any individual underlies the need for health care insurance. However, improved life expectancy, resulting in part from effective treatments of cardiovascular and respiratory disease, HIV infection and some cancers,5 as well as the chronic debilitating effects of conditions, such as severe stroke or heart failure, are contributing to rising numbers of chronically high users of health care resources. Yet, little is known about the sustained use of health care services among high-cost users.Previous studies of high-cost users in the US have been limited by the use of survey respondents as a source population1 or included only patients in private insurance systems who were less than 65 years of age.6,7 Studies in Canada have examined spending on acute hospital, physician or nursing home care only, representing less than half of all health care expenditures.2,3 Age-related patterns have not been compared.We conducted a study to make a system-wide assessment of the concentration and persistence of costs in a comprehensive health care system. We had several objectives: to measure total expenditures of publicly insured care for every individual, and by health care sector, in the province of Ontario between 2009 and 2011; to track expenditure patterns for individuals over a 3-year period; to describe the concentration of health care spending among different age groups; and to identify the main diagnoses among high-cost users.  相似文献   
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The neuroendocrine hormone oxytocin, which is an important physiological driver of social behavior and bonding, is increasingly being measured in conjunction with behavior to better understand primate sociality. To date no data are available on oxytocin concentrations within the genus Gorilla; however, as a result of their close genetic relatedness to humans, and tolerance-based social system, Gorilla represents an important group of study. The purpose of this study was to validate the measurement of urinary and salivary oxytocin in western lowland gorillas (Gorilla gorilla gorilla) to help facilitate future study of the interaction between oxytocin and behavior within the subspecies. The primary validation procedure was an intranasal challenge. Elevated oxytocin concentrations were observed in saliva samples taken 15–120 min post challenge. Urine levels remained within baseline range approximately 30 and 90 min following the challenge; however, elevated levels were observed 24 h post challenge. No diurnal variation was found in salivary samples taken at regular intervals throughout the day; however, morning urine samples had higher concentrations than afternoon samples. In addition, samples were collected opportunistically following three social events: play, breeding, and the death of a conspecific. Following the play bouts, salivary oxytocin was almost three times greater than baseline. Salivary oxytocin was also significantly higher 15 min post breeding compared to match-control samples. Following the death of a conspecific, the group mate’s urinary oxytocin concentrations decreased by half compared to a baseline period when the group was intact. This study provides a biological validation of the measurement of urinary and salivary oxytocin in western lowland gorillas. These results suggest that urinary oxytocin measurements are suitable for establishing baseline levels, as they represent the build up of the previous day’s concentrations, and salivary oxytocin measurements are suitable for assessing changes following specific events.  相似文献   
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Scavenging is an important component to the overall ecology of consumers in virtually all ecosystems on Earth. Given the energetic benefits of foraging on these resource subsidies, opportunistic predators will adjust their behaviors accordingly to maximize access. One of the many consequences of large-scale scavenging opportunities is species interactions that are rarely observed in nature. Here we describe the first published record of predatory sharks (tiger sharks, Galeocerdo cuvier) and saltwater crocodiles (Crocodylus porosus) foraging together in space and time, as documented on a large whale carcass off Western Australia. We report on and discuss the behaviors of the sharks and crocodiles in the hope of shedding new light on the interactions between apex predators that are rarely seen together, but may overlap under specific contexts.  相似文献   
998.
The risk of cancer associated with a broad range of organ doses was estimated in an international study of women with cervical cancer. Among 150,000 patients reported to one of 19 population-based cancer registries or treated in any of 20 oncology clinics, 4188 women with second cancers and 6880 matched controls were selected for detailed study. Radiation doses for selected organs were reconstructed for each patient on the basis of her original radiotherapy records. Very high doses, on the order of several hundred gray, were found to increase the risk of cancers of the bladder [relative risk (RR) = 4.0], rectum (RR = 1.8), vagina (RR = 2.7), and possibly bone (RR = 1.3), uterine corpus (RR = 1.3), cecum (RR = 1.5), and non-Hodgkin's lymphoma (RR = 2.5). For all female genital cancers taken together, a sharp dose-response gradient was observed, reaching fivefold for doses more than 150 Gy. Several gray increased the risk of stomach cancer (RR = 2.1) and leukemia (RR = 2.0). Although cancer of the pancreas was elevated, there was no evidence of a dose-dependent risk. Cancer of the kidney was significantly increased among 15-year survivors. A nonsignificant twofold risk of radiogenic thyroid cancer was observed following an average dose of only 0.11 Gy. Breast cancer was not increased overall, despite an average dose of 0.31 Gy and 953 cases available for evaluation (RR = 0.9); there was, however, a weak suggestion of a dose response among women whose ovaries had been surgically removed. Doses greater than 6 Gy to the ovaries reduced breast cancer risk by 44%. A significant deficit of ovarian cancer was observed within 5 years of radiotherapy; in contrast, a dose response was suggested among 10-year survivors. Radiation was not found to increase the overall risk of cancers of the small intestine, colon, ovary, vulva, connective tissue, breast, Hodgkin's disease, multiple myeloma, or chronic lymphocytic leukemia. For most cancers associated with radiation, risks were highest among long-term survivors and appeared concentrated among women irradiated at relatively younger ages.  相似文献   
999.
Human genome and exome sequencing are powerful research tools that can generate secondary findings beyond the scope of the research. Most secondary genomic findings are of low importance, but some (for a current estimate of 1%–3% of individuals) confer high risk of a serious disease that could be mitigated by timely medical intervention. The impact and scope of secondary findings in genome and exome sequencing will only increase in the future. There is considerable agreement that high-impact findings should be returned to participants, but many researchers performing genomic research studies do not have the background, skills, or resources to identify, verify, interpret, and return such variants. Here, we introduce a proposal for the formation of a secondary-genomic-findings service (SGFS) that would support researchers by enabling the return of clinically actionable sequencing results to research participants in a standardized manner. We describe a proposed structure for such a centralized service and evaluate the advantages and challenges of the approach. We suggest that such a service would be of greater benefit to all parties involved than present practice, which is highly variable. We encourage research centers to consider the adoption of a centralized SGFS.  相似文献   
1000.
The Heike Nôkyô, Japanese scrolls of Buddhist sutras created in 1164 AD, includes illustrations of anIpomoea that has long been identified by Japanese scholars asI. nil. What makes this occurrence ofI. nil in pre-Columbian Japan remarkable is that all of its closest relatives are American plants. We give a synopsis of the history of this economically important species. Then, using cladistic analysis, we show the relationships ofI. nil toI.eriocalyx,I. hederacea,I. indica,I. laeta,I. lindheimeri,I. meyeri, andI. pubescens. Six of these eight species inIpomoea seriesHeterophyllae are endemic to the New World.Ipomoea indica is pantropical, and may be carried by ocean currents. We offer four hypotheses as to how this putatively tropical American species may have arrived in Asia: 1)Ipomoea nil was introduced through long-distance dispersal by animals; 2)Ipomoea nil was introduced by humans in a pre-Columbian context; 3) TheIpomoea in theHeike Nôkyô scrolls does not representI. nil, but a different native Asian species; and 4)Ipomoea nil was introduced during post-Columbian times by Europeans. There are problems with accepting any of these possible alternatives.  相似文献   
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