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The temporal bone anatomy is complex, with many critical structures in close association with one another. The temporal bone region comprises cranial nerves V, VI, VII, and VIII; vascular structures such as the internal carotid and middle meningeal arteries; sigmoid sinus; jugular bulb; and sensorineural and membranous structures of the inner ear. Most temporal bone fractures are a result of high-energy blunt head trauma. Multidetector computed tomography (CT) plays a fundamental role in the initial evaluation of patients with polytrauma in the emergency department. Multidetector CT may help identify important structural injuries that may have devastating complications such as sensorineural hearing loss, conductive hearing loss, dizziness and balance dysfunction, perilymphatic fistulas, cerebrospinal fluid leaks, facial nerve paralysis, and vascular injury. Although classifying temporal bone fractures helps physicians understand and predict trauma-associated complications and guide treatment, identifying injury to critical structures is more important for guiding management and determining prognosis than is simply classifying temporal bone fractures into a general category. Many temporal bone fractures and complications may be readily identified and characterized at routine cervical, maxillofacial, and head multidetector CT performed in patients with polytrauma, without the need for dedicated temporal bone multidetector CT. Dedicated temporal bone multidetector CT should be considered when there is a high degree of suspicion for temporal bone fractures and no fractures are identified at head, cervical, or maxillofacial CT. 相似文献
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Brandon DL. Marshall Evan Wood Jean A. Shoveller Jane A. Buxton Julio SG. Montaner Thomas Kerr 《Prevention science》2011,12(2):173-180
The purpose of this study was to determine the incidence and predictors of initiating methamphetamine injection among a cohort
of injection drug users (IDU). We conducted a longitudinal analysis of IDU participating in a prospective study between June
2001 and May 2008 in Vancouver, Canada. IDU who had never reported injecting methamphetamine at the study’s commencement were
eligible. We used Cox proportional hazards models to identify the predictors of initiating methamphetamine injection. The
outcome was time to first report of methamphetamine injection. Time-updated independent variables of interest included sociodemographic
characteristics, drug use patterns, and social, economic and environmental factors. Of 1317 eligible individuals, the median
age was 39.9 and 522 (39.6%) were female. At the study’s conclusion, 200 (15.2%) participants had initiated injecting methamphetamine
(incidence density: 4.3 per 100 person-years). In multivariate analysis, age (adjusted hazard ratio [aHR]: 0.96 per year older,
95%CI: 0.95–0.98), female sex (aHR: 0.58, 95%CI: 0.41–0.82), sexual abuse (aHR: 1.63, 95%CI: 1.18–2.23), using drugs in Vancouver’s
drug scene epicentre (aHR: 2.15 95%CI: 1.49–3.10), homelessness (aHR: 1.43, 95%CI: 1.01–2.04), non-injection crack cocaine
use (aHR: 2.06, 95%CI: 1.36–3.14), and non-injection methamphetamine use (aHR: 3.69, 95%CI: 2.03–6.70) were associated with
initiating methamphetamine injection. We observed a high incidence of methamphetamine initiation, particularly among young
IDU, stimulant users, homeless individuals, and those involved in the city’s open drug scene. These data should be useful
for the development of a broad set of interventions aimed at reducing initiation into methamphetamine injection among IDU. 相似文献
996.
Substance abuse is linked to many new cases of HIV infection. Barriers such as the myth that drug users cannot adhere to HIV/AIDS treatment block progress in curbing the spread of HIV in that population. In this article we explain the need to aggressively seek out high-risk, hard-to-reach substance abusers and to offer them HIV testing, access to treatment, and the necessary support to remain in treatment--both for HIV and for substance abuse. We summarize evidence showing that injection drug users can successfully undergo HIV treatment; that many substance abusers adhere to antiretroviral therapy as well as do people who don't inject drugs; and that injection drug users who undergo substance abuse treatment are more likely to obtain and stay in treatment for their HIV infection. This evidence makes a strong case for integrating substance abuse treatment with HIV treatment programs and providing substance abusers with universal access to HIV treatment. But an integrated strategy will require changes in the health care system to overcome lingering obstacles that inhibit the merging of substance abuse treatment with HIV programs. 相似文献
997.
Josip Jakovac Leonardo Marui Denise Andrade-Guevara Julio C. Chacn-Torres Vito Despoja 《Materials》2021,14(15)
A theoretical formulation of the electromagnetic response in graphene ribbons on dielectric substrate is derived in the framework of the ab initio method. The formulation is applied to calculate the electromagnetic energy absorption in an array of potassium-doped graphene nanoribbons (KC-NR) deposited on a dielectric AlO substrate. It is demonstrated that the replacement of the flat KC by an array of KC-NR transforms the Drude tail in the absorption spectra into a series of infrared-active Dirac plasmon resonances. It is also shown that the series of Dirac plasmon resonances, when unfolded across the extended Brillouin zones, resembles the Dirac plasmon. The Dirac plasmon resonances’ band structure, within the first Brillouin zone, is calculated. Finally, an excellent agreement between the theoretical absorption and recent experimental results for differential transmission through graphene on an SiO/Si surface is presented. The theoretically predicted micrometer graphene nanoribbons intercalation compound (GNRIC) in a stage-I-like KC is confirmed to be synthesized for Dirac plasmon resonances. 相似文献
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Ehud Elnekave Samuel L. Hong Seunghyun Lim Dave Boxrud Albert Rovira Alison E. Mather Andres Perez Julio Alvarez 《Emerging infectious diseases》2020,26(12):3034
Multidrug-resistant Salmonella enterica subspecies enterica 4,[5],12:i:- sequence type 34 represents a worldwide public health risk. To determine its origin in the United States, we reconstructed a time-scaled phylogeny with a discrete trait geospatial model. The clone in the United States was introduced from Europe on multiple occasions in the early 2000s. 相似文献
1000.
Marianela Bayn Cabeza Francisco Javier Prez Rivas Ana Leonor Zamora Sarabia Julio de las Heras Mosteiro Beatriz Becerril Rojas Ricardo Rodriguez Barrientos 《Atencion primaria / Sociedad Espa?ola de Medicina de Familia y Comunitaria》2020,52(9):617-626
ObjectiveTo study the effect of the type of follow-up according to Service Portfolio and other associated factors, in the reduction of HbA1c levels in people with a new diagnosis of type 2 diabetes and poor initial control.DesignAnalytical observational study of a cohort under routine clinical practice conditions.Location262 Primary Health Care Centres in Madrid.Participants1,838 individuals older than 18 years with a new diagnosis of type 2 DM and initial HbA1c levels ≥ 7%, or ≥ 8.5% if older than 75 years.InterventionsThe exposure variable was the type of follow-up according to Portfolio, categorised as minimum, medium, and optimal, according to the number of interventions performed and periodicity of type of therapeutic-pharmacological plan.Main measurementsA study was made of the comorbidity, therapeutic-pharmacological plan, diet - exercise advice and deprivation index. The main outcome was the difference between the final and initial HbA1c.ResultsAfter 2 years of follow-up there was a mean decrease in HbA1c by -1.7 percentage points (95% CI: -1.6;-1.8), which was 0.36 points higher in patients with optimal follow-up: -2.1 (95% CI: -1.7;-2.4). The factors associated with a decrease in HbA1c were the optimal follow-up -0.29 (95% CI: -0.5;-0.1), the medium follow-up -0.26 (95% CI: -0.5; -0.0), and the initial HbA1c value -0.9 (95% CI: -0.9; -0.9. The factors associated with the increase were insulin treatment and living in socially disadvantaged areas.ConclusionsGlycaemic control was improved in patients with a new diagnosis of diabetes in which optimal follow-up is performed as proposed in the Service Portfolio. 相似文献