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481.
It is a well-documented fact that pontomedullary lacerations (PML) occur as a result of severe craniocervical injury, but their underlying mechanism has yet to be fully clarified. The aim of this prospective study has been to give greater insight into the underlying mechanism of PML through determining the site of blunt head-impact, as well as the presence of concomitant head and neck injuries in cases of brainstem PML. A total of 56 cases with partial PML have been analysed for this study. The case group was composed of 40 men and 16 women, averaging in age 44.2 ± 19.2 years and consisting of 7 motorcyclists, 4 bicyclists, 18 car occupants, 16 pedestrians, and 10 victims of falls from a height, as well as 1 victim of a fall from standing height. The presented study has shown that there are several possible mechanisms of PML. Impact to the chin, with or without a skull base fracture, most often leads to this fatal injury, due to the impact force transmission either through the jawbone or vertebral column; most likely in combination with a fronto-posterior hyperextension of the head. Additionally, lateral head-impacts with subsequent hinge fractures and PML may also be a possible mechanism. The jawbone and other facial bones are able to act as shock absorbers, and their fracture may diminish the energy transfer towards the skull and protect the brain and brainstem from injury. The upper cervical spine can act as damper and energy absorber as well, and may prevent any occurrence of fracture to the base of the skull.  相似文献   
482.
Coronary microcirculatory function after primary percutaneous coronary intervention (pPCI) in patients with acute myocardial infarction is important determinant of infarct size (IS). Our aim was to investigate the utility of coronary flow reserve (CFR) and diastolic deceleration time (DDT) of the infarct artery (IRA) assessed by transthoracic Doppler echocardiography after pPCI for final IS prediction. In 59 patients, on the 2nd day after pPCI for acute anterior myocardial infarction, transthoracic Doppler analysis of IRA blood flow was done including measurements of CFR, baseline DDT and DDT during adenosine infusion (DDT adeno). Killip class, myocardial blush grade, resolution of ST segment elevation, peak creatine kinase-myocardial band and conventional echocardiographic parameters were determined. Single-photon emission computed tomography myocardial perfusion imaging was done 6 weeks later to define final IS (percentage of myocardium with fixed perfusion abnormality). IS significantly correlated with CFR (r = ?0.686, p < 0.01), DDT (r = ?0.727, p < 0.01), and DDT adeno (r = ?0.780, p < 0.01). CFR and DDT adeno in multivariate analysis remained independent IS predictors after adjustment for other covariates and offered incremental prognostic value in models based on conventional clinical, angiographic, electrocardiographic and enzymatic variables. In predicting large infarction (IS > 20 %), the best cut-off for CFR was <1.73 (sensitivity 65 %, specificity 96 %) and for DDT adeno ≤720 ms (sensitivity 81 %, specificity 96 %). CFR and DDT during adenosine are independent and powerful early predictors of final IS offering incremental prognostic information over conventional parameters of myocardial and microvascular damage and tissue reperfusion.  相似文献   
483.
484.
Xanthohumol (XN) and isoxanthohumol (IXN), prenylated flavonoids from Humulus lupulus, have been shown to possess antitumor/cancerprotective, antioxidant, antiinflammatory, and antiangiogenic properties. In this study, mesoporous silica (SBA-15) was loaded with different amounts of xanthohumol and isoxanthohumol and characterized by standard analytical methods. The anticancer potential of XN and IXN loaded into SBA-15 has been evaluated against malignant mouse melanoma B16F10 cells. When these cells were treated with SBA-15 containing xanthohumol, an increase of the activity correlated with a higher immobilization rate of XN was observed. Considering the amount of XN loaded into SBA-15 (calculated from TGA), an improved antitumor potential of XN was observed (IC50 = 10.8 ± 0.4 and 11.8 ± 0.5 µM for SBA-15|XN2 and SBA-15|XN3, respectively; vs. IC50 = 18.5 ± 1.5 µM for free XN). The main mechanism against tumor cells of immobilized XN includes inhibition of proliferation and autophagic cell death. The MC50 values for SBA-15 loaded with isoxanthohumol were over 300 µg/mL in all cases investigated.  相似文献   
485.

Background

Deprescribing (reduction or cessation) of prescribed opioids can be challenging for both patients and healthcare professionals.

Objective

To synthesize and evaluate evidence from systematic reviews examining the effectiveness and outcomes of patient-targeted opioid deprescribing interventions for all types of pain.

Methods

Systematic searches were conducted in five databases with results screened against predetermined inclusion/exclusion criteria. Primary outcomes were (i) reduction in opioid dose, reported as change in oral Morphine Equivalent Daily Dose (oMEDD) and (ii) success of opioid deprescribing, reported as the proportion of the sample for which opioid use declined. Secondary outcomes included pain severity, physical function, quality of life and adverse events. The certainty of evidence was assessed using Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology.

Findings

Twelve reviews were eligible for inclusion. Interventions were heterogeneous in nature and included pharmacological (n = 4), physical (n = 3), procedural (n = 3), psychological or behavioural (n = 3) and mixed (n = 5) interventions. Multidisciplinary care programmes appeared to be the most effective intervention for opioid deprescribing; however, the certainty of evidence was low, with significant variability in opioid reduction across interventions.

Conclusions

Evidence is too uncertain to draw firm conclusions about specific populations who may derive the greatest benefit from opioid deprescribing, warranting further investigation.  相似文献   
486.

Background

Frailty is an important determinant of health-care needs and outcomes for people in hospital.

Objectives

To compare characteristics and predictive ability of a multidomain frailty index derived from routine health data (electronic frailty index-acute hospital; eFI-AH) with the hospital frailty risk score (HFRS).

Methods

This retrospective study included 6771 patients aged ≥75 years admitted to an Australian metropolitan tertiary referral hospital between October 2019 and September 2020. The eFI-AH and the HFRS were calculated for each patient and compared with respect to characteristics, agreement, association with age and ability to predict outcomes.

Results

Median eFI-AH was 0.17 (range 0–0.66) whilst median HFRS was 3.2 (range 0–42.9). Moderate agreement was shown between the tools (Pearson's r 0.61). After adjusting for age and gender, both models had associations with long hospital stay, in-hospital mortality, unplanned all-cause readmission and fall-related readmission. Specifically, the eFI-AH had the strongest association with in-hospital mortality (adjusted odds ratio (aOR) 2.81, 95% confidence intervals (CI) 2.49–3.17), whilst the HFRS was most strongly associated with long hospital stay (aOR 1.20, 95% CI 1.18–1.21). Both tools predicted hospital stay >10 days with good discrimination and calibration.

Conclusions

Although the eFI-AH and the HFRS did not consistently identify the same inpatients as frail, both were associated with adverse outcomes and they had comparable predictive ability for prolonged hospitalisation. These two constructs of frailty may have different implications for clinical practice and health service provision and planning.  相似文献   
487.
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