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991.
Aggression and violence are widespread in UK Mental Health Trusts, and are accompanied by negative psychological and physiological consequences for both staff and other patients. Patients who are younger, male, and have a history of substance use and psychosis diagnoses are more likely to display aggression; however, patient factors are not solely responsible for violence, and there are complex circumstances that lead to aggression. Indeed, patient–staff interactions lead to a sizeable portion of aggression and violence on inpatient units, thus they cannot be viewed without considering other forms of conflict and containment that occur before, during, and after the aggressive incident. For this reason, we examined sequences of aggressive incidents in conjunction with other conflict and containment methods used to explore whether there were particular profiles to aggressive incidents. In the present study, 522 adult psychiatric inpatients from 84 acute wards were recruited, and there were 1422 incidents of aggression (verbal, physical against objects, and physical). Cluster analysis revealed that aggressive incident sequences could be classified into four separate groups: solo aggression, aggression–rule breaking, aggression–medication, and aggression–containment. Contrary to our expectations, we did not find physical aggression dominant in the aggression–containment cluster, and while verbal aggression occurred primarily in solo aggression, physical aggression also occurred here. This indicates that the management of aggression is variable, and although some patient factors are linked with different clusters, these do not entirely explain the variation.  相似文献   
992.
993.
Data are presented from the Baltimore Young Men’s Survey, a cross-sectional, venue-based sample survey of risks associated with HIV and report of a prior HIV test, conducted between 1996 and 2000, and enrolling 843 young men who have sex with men (MSM) aged 15–29 years. HIV prevalence was 12.1% overall and racial disparities in HIV prevalence were pronounced (range, 2.9% among non-Hispanic whites to 27.1% among non-Hispanic blacks). Risks independently associated with being HIV-positive were: being between 26 and 29 years of age, being non-Hispanic black or of other/mixed race, having had 20 or more lifetime male sex partners, having been diagnosed with a sexually transmitted disease (STD), and not being currently enrolled in school. The majority of participants (78.9%) reported a prior HIV test. In multivariate analysis, being older, having had five or more lifetime male sex partners, having had anal intercourse with males, reporting an STD diagnosis, and reporting recent unprotected anal sex were associated with report of a prior HIV test. Prevention efforts must address high HIV prevalence among young non-Hispanic black MSM and must make testing and effective counseling for young MSM readily available.  相似文献   
994.
995.
Aim: The aim of this study was to identify echocardiographic LV systolic and diastolic measurements that predict clinical events post–coronary artery bypass graft (CABG) surgery. Methods: We collected data from 27 patients (age 70 ± 7 years) who underwent elective CABG, before and within 6 weeks after surgery. LV systolic function was assessed by conventional echocardiographic parameters. A number of LV filling measurements were also made, which included total isovolumic time (t-IVT), Tei index, and restrictive filling pattern. Postoperative cardiac events were death or hospitalization for chest pain, breathlessness, or arrhythmia. Results: Patient's follow-up period was 17 ± 10 months. Of the 27 patients (age 70 ± 7 years, 22 male), 10 had postoperative cardiac events. LV ejection fraction (EF) and fractional shortening (FS) were lower (P = 0.01, and P = 0.007, respectively), t-IVT longer (P < 0.001), and Tei index was higher (P < 0.001) preoperatively in patients with events compared to those without. The same differences between groups remained after surgery; EF (P = 0.002), FS (P = 0.002), t-IVT (P < 0.001), and Tei index (P < 0.001). T-IVT was the only preoperative predictor of events (P = 0.038) but its postoperative value as well as that of FS predicted events (P = 0.034, and P = 0.042, respectively). T-IVT of 12.2 s/min and FS of 26% were 80% sensitive and 88% specific for predicting postoperative events. Conclusion: Despite successful surgical revascularization residual impairment of LV systolic function and persistent asynchrony in the form of prolonged t-IVT are associated with postoperative events. Since these abnormalities remained despite full medical therapy, they may thus suggest a need for electrical resynchronization therapy. (Echocardiography 2010;27:32-37)  相似文献   
996.
Although water-soluble polymers are finding increasing use as polymer therapeutics, there has been little consideration of the effect of polymer stereochemistry on their physico-chemical and biological properties. The aim of this study was to investigate these properties using polymethacrylic acids (PMAs) of similar molecular weights with a difference in syndiotacticity of about 20% of rr triad content. Experiments to characterize the solution behaviour were conducted at pHs encountered during the transport, endocytic uptake and intracellular trafficking (7.4-3.0). These showed that with increasing rr triads, the polymer become less hydrophobic, a stronger acid, displayed a locally ordered solution conformation at pH 5.5, and interacted more strongly with dodecyl trimethylammonium bromide (DTAB) micelles. Preliminary cytotoxicity experiments using B16F10 melanoma cells showed lower toxicity in the concentration range of 1-100 μg/mL with increased rr triads. These observations indicate that the higher content of rr triads could drive a chain organization that minimize the influence of negative charges and so underline the importance of further, systematic studies to investigate the effect of tacticity on the behaviour of polymers in respect of their pharmacokinetics, toxicity and efficacy.  相似文献   
997.
998.
Sulfur mustard (SM) is a highly toxic chemical warfare agent that remains a threat to human health. The immediate symptoms of pulmonary distress may develop into chronic lung injury characterized by progressive lung fibrosis, the major cause of morbidity among the surviving SM victims. Although SM has been intensely investigated, little is known about the mechanism(s) by which SM induces chronic lung pathology. Increasing evidence suggests that IL-17(+) cells are critical in fibrosis, including lung fibrotic diseases. In this study we exposed F344 rats and cynomolgus monkeys to SM via inhalation and determined the molecular and cellular milieu in their lungs at various times after SM exposure. In rats, SM induced a burst of pro-inflammatory cytokines/chemokines within 72 h, including IL-1β, TNF-α, IL-2, IL-6, CCL2, CCL3, CCL11, and CXCL1 that was associated with neutrophilic infiltration into the lung. At 2 wks and beyond (chronic phase), lymphocytic infiltration and continued elevated expression of cytokines/chemokines were sustained. TGF-β, which was undetectable in the acute phase, was strongly upregulated in the chronic phase; these conditions persisted until the animals were sacrificed. The chronic phase was also associated with myofibroblast proliferation, collagen deposition, and presence of IL-17(+) cells. At ≥30 days, SM inhalation promoted the accumulation of IL-17(+) cells in the inflamed areas of monkey lungs. Thus, SM inhalation causes acute and chronic inflammatory responses; the latter is characterized by the presence of TGF-β, fibrosis, and IL-17(+) cells in the lung. IL-17(+) cells likely play an important role in the pathogenesis of SM-induced lung injury.  相似文献   
999.
Since their initial discovery, endothelial progenitor cells (EPCs) have held tremendous promise for cell therapy for a variety of cardiovascular diseases including pulmonary hypertension. The clinical experience to date suggests that circulating or bone marrow mononuclear cells and EPCs can induce neovascularization, and enhance cardiac repair after myocardial function, as well as improvements in the hemodynamic and functional status of patients with idiopathic pulmonary arterial hypertension. Although these results are promising, the overall magnitude of the clinical benefits seen in these trials appear to be rather modest. Indeed, strong experimental evidence points towards a reduction in mobilization and impairment in function of EPCs in preclinical models and patients with cardiac disease or with cardiovascular risk factors such as advanced age, type I and II diabetes, hypercholesterolemia, coronary artery disease, as well as other conditions such as pulmonary hypertension. Genetic engineering of EPCs ex vivo, prior to transplantation, is a promising cell-enhancement strategy for restoring the angiogenic potential of autologous, patient-derived cells. This review provides an update of the experimental studies that have used gene-modified EPC therapy to treat ischemic cardiovascular disease and pulmonary hypertension.  相似文献   
1000.

Purpose

The phase composition and distribution of ethylcellulose (EC) films containing varying amounts of the plasticizer fractionated coconut oil (FCO) were studied using a novel combination of thermal and mapping approaches.

Methods

The thermal and thermomechanical properties of films containing up to 30% FCO were characterized using modulated temperature differential scanning calorimetry (MTDSC) and dynamic mechanical analysis (DMA). Film surfaces were mapped using atomic force microscopy (AFM; topographic and pulsed force modes) and the composition of specific regions identified using nanothermal probes.

Results

Clear evidence of distinct conjugate phases was obtained for the 20?C30% FCO/EC film systems. We suggest a model whereby the composition of the distinct phases may be estimated via consideration of the glass transition temperatures observed using DSC and DMA. By combining pulsed force AFM and nano-thermal analysis we demonstrate that it is possible to map the two separated phases. In particular, the use of thermal probes allowed identification of the distinct regions via localized thermomechanical analysis, whereby nanoscale probe penetration is measured as a function of temperature.

Conclusion

The study has indicated that by using thermal and imaging techniques in conjunction it is possible to both identify and map distinct regions in binary films.  相似文献   
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