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101.
Background
Defensive medicine is the practice of diagnostic or therapeutic measures conducted primarily as a safeguard against possible malpractice liability. We studied the extent, reasons, and characteristics of defensive medicine in the Israeli health care system.Methods and Findings
Cross-sectional study performed in the Israeli health care system between April and July 2008 in a sample (7%) of board certified physicians from eight medical disciplines (internal medicine, pediatrics, general surgery, family medicine, obstetrics and gynecology, orthopedic surgery, cardiology, and neurosurgery). A total of 889 physicians (7% of all Israeli board certified specialists) completed the survey. The majority [60%, (95%CI 0·57–0·63)] reported practicing defensive medicine; 40% (95%CI 0·37–0·43) consider every patient as a potential threat for a medical lawsuit; 25% (95%CI 0·22–0·28) have previously been sued at least once during their career. Independent predictors for practicing defensive medicine were surgical specialty [OR = 1.6 (95%CI 1·2–2·2), p = 0·0004], not performing a fellowship abroad [OR = 1·5 (95%CI 1·1–2), p = 0·027], and previous exposure to lawsuits [OR = 2·4 (95%CI 1·7–3·4), p<0·0001]. Independent predictors for the risk of being sued during a physician''s career were male gender [OR = 1·6 (95%CI 1·1–2·2), p = 0·012] and surgery specialty [OR = 3·2 (95%CI 2·4–4·3), p<0·0001] (general surgery, obstetrics and gynecology, orthopedic surgery, and neurosurgery).Conclusions
Defensive medicine is very prevalent in daily physician practice in all medical disciplines. It exposes patients to complications due to unnecessary tests and procedures, affects quality of care and costs, and undermines doctor-patient relationships. Further studies are needed to understand how to minimize defensive medicine resulting from an increased malpractice liability market. 相似文献102.
I Le Viol F Jiguet L Brotons S Herrando A Lindström JW Pearce-Higgins J Reif C Van Turnhout V Devictor 《Biology letters》2012,8(5):780-782
Biotic homogenization (BH) is a process whereby some species (losers) are systematically replaced by others (winners). While this process has been related to the effects of anthropogenic activities, whether and how BH is occurring across regions and the role of native species as a driver of BH has hardly been investigated. Here, we examine the trend in the community specialization index (CSI) for 234 native species of breeding birds at 10 111 sites in six European countries from 1990 to 2008. Unlike many BH studies, CSI uses abundance information to estimate the balance between generalist and specialist species in local assemblages. We show that bird communities are more and more composed of native generalist species across regions, revealing a strong, ongoing BH process. Our result suggests a rapid and non-random change in community composition at a continental scale is occurring, most likely driven by anthropogenic activities. 相似文献
103.
Roberto Reif Jia Qin Lei Shi Suzan Dziennis Zhongwei Zhi Alfred L. Nuttall Ruikang K. Wang 《PloS one》2012,7(12)
A synchronized dual-wavelength laser speckle contrast imaging (DWLSCI) system and a Doppler optical microangiography (DOMAG) system was developed to determine several ischemic parameters in the cochlea due to a systemic hypoxic challenge. DWLSCI can obtain two-dimensional data, and was used to determine the relative changes in cochlear blood flow, and change in the concentrations of oxyhemoglobin (HbO), deoxyhemoglobin (Hb) and total hemoglobin (HbT) in mice. DOMAG can obtain three-dimensional data, and was used to determine the changes in cochlear blood flow with single vessel resolution. It was demonstrated that during a hypoxic challenge there was an increase in the concentrations of Hb, a decrease in the concentrations of HbO and cochlear blood flow, and a slight decrease in the concentration of HbT. Also, the rate of change in the concentrations of Hb and HbO was quantified during and after the hypoxic challenge. The ability to simultaneously measure these ischemic parameters with high spatio-temporal resolution will allow the detailed quantitative analysis of several hearing disorders, and will be useful for diagnosing and developing treatments. 相似文献
104.
Shimon L Hynes GM McCormack EA Willison KR Horovitz A 《Journal of molecular biology》2008,377(2):469-477
Saccharomyces cerevisiae yeast cells containing the chaperonin CCT (chaperonin-containing t-complex polypeptide 1 (TCP-1)) with the G345D mutation in subunit CCT4 (anc2-1) are temperature-sensitive for growth and display defects in organization of actin structure, budding and cell shape. In this first structure-function analysis of CCT, we show that this mutation abolishes both intra- and inter-ring cooperativity in ATP binding by CCT. The finding that a single mutation in only one subunit in each CCT ring has such drastic effects highlights the importance of allostery for its in vivo function. These results, together with other kinetic data for wild-type CCT reported in this study, provide support for the sequential model for ATP-dependent allosteric transitions in CCT. 相似文献
105.
Regulatory T cells (Tregs) play an indispensable role in maintaining immunological unresponsiveness to self-antigens and in suppressing excessive immune responses deleterious to the host. Tregs are produced in the thymus as a functionally mature subpopulation of T cells and can also be induced from naive T cells in the periphery. Recent research reveals the cellular and molecular basis of Treg development and function and implicates dysregulation of Tregs in immunological disease. 相似文献
106.
In 2000, a severe outbreak of phytoplasma-caused disease in Limonium spp. flowers devastated the industry in Israel; insecticides were not able to knock down and kill leafhopper vectors before they could transmit the pathogen. Nonchoice laboratory studies were conducted to determine the effect of UV-absorbing plastics on the movement of leafhoppers toward light; UV-absorbing plastic significantly reduced leafhopper movement. In choice trials conducted in sunlight, significantly more leafhoppers moved into the cage covered with regular plastic as opposed to the cage covered with UV-absorbing plastic. Field studies were conducted to determine at what height leafhoppers enter 2.5-3-m high walk-in tunnels; the majority enter the tunnels low to the ground, up to 1 m. Finally, field studies were conduced to compare leafhopper population levels in walk-in tunnels covered with UV-absorbing plastic or screening, and with ventilation holes at different heights above the ground. Elevated ventilation holes and UV-absorbing tunnel covering significantly reduced Orosius orientalis entrance into tunnels. Ramifications of these finding for leafhopper control are discussed. 相似文献
107.
The potato tuber moth Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae) is a major agricultural pest of solaneceous crops in warm countries worldwide. The encyrtid polyembryonic parasitoid Copidosoma koehleri (Blanchard) has been successfully introduced for biological control of the moth in potato fields in South Africa and Australia; however, augmentative releases of the parasitoid in trial plots and in commercial potato fields in Israel did not reduce pest populations or infestation levels more than chemical treatment. Copidosoma koehleri accounted for 4–5% of parasitism on tuber moth caterpillars, while most parasitism was due to local species of larval parasitoids. The abundance and composition of local parasitoids did not differ between C. koehleri release plots and conventionally treated control plots. These findings can be interpreted as failure of the introduced parasitoids to survive and locate their hosts, or as mortality of C. koehleri within hosts in the field. Sentinel hosts, placed in trial plots and collected after 24 h, were rarely parasitised by C. koehleri, supporting the first interpretation. To test the second hypothesis, hosts parasitised by C. koehleri were placed in field plots for a week, collected, and reared out in the laboratory. The emergence rates of C. koehleri from these hosts resembled those of lab-reared controls, suggesting that mortality within hosts in the field is not a major cause of C. koehleri's poor biocontrol performance. 相似文献
108.
109.
110.
The impact of forest transformation on stand structure and ground vegetation in the southern Black Forest, Germany 总被引:1,自引:0,他引:1
The goal of this study was to investigate the effects of 'ecologically orientated' forest transformation on forest floor vegetation. Forest transformation, as defined by the BMBF southern Black Forest project group, is the process which converts even-aged spruce forest into structured continuous-cover forest, consisting principally of spruce (Picea abies), fir (Abies alba) and beech (Fagus sylvatica). In order to analyse the transformation process, four transformation stages were defined as part of a 'conceptual forest development model' (pure even-aged, species enrichment, structuring and continuous cover forest stage). Four forest districts representative of the southern Black Forest were selected for the study. The analysis included the separate classification of structures, sites, and ground vegetation. In a second step, the relationships between the three complexes were analysed. The influence of forest structure on ground vegetation was investigated by examining the relationships between so-called substructure types and ground vegetation types. The substructure types associated with the pure spruce stand, species enrichment and continuous cover forest stages exhibited a ground vegetation resembling that of the Luzulo-Fagetum and Luzulo-Abietetum, whereas the structuring stages exhibited a ground vegetation of the Galio-Fagetum type. Transformation of pure, even-aged spruce forest into mixed, uneven-aged continuous cover forest is considered an important silvicultural tool to combine the demands of sustainable timber production and nature conservation. Transformation brings about greater diversity in stand structure and tree species composition. The frequencies of acidophytic mosses and vascular plants in spruce forest decrease during the transformation process. The species requiring moderate base supply increase over the transitional stages. The continuous cover forest, the final stage of transformation, increasingly contains ground species of both, i.e., species normally associated with both conifer and deciduous forest. 相似文献