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Securinega virosa is used traditionally as sedative in children and in mental illnesses. In this study, the behavioral effects of methanolic root bark extract of S. virosa were investigated in mice. The results revealed that the extract significantly (P<0.05) and dose-dependently reduced the onset and prolonged the duration of sleep. The extract significantly (P<0.05) decreased exploratory activity and reduced the rate of apomorphine-induced stereotyped climbing at the doses tested (6.25–25mg/kg). It also produced a significant and dose-dependent motor coordination deficit in mice at the doses tested (P<0.01). The intraperitoneal median lethal dose in mice was 774.6mg/kg while the preliminary phytochemical screening revealed the presence of alkaloids, tannins, saponins and flavonoids. These results suggest that methanolic root bark extract of S. virosa contains biologically active principles that are sedative in nature and lend pharmacological credence to the ethnomedical use of the plant.  相似文献   
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We examined changes in suicide rates among 10–24-year-olds in the United States from 1992 to 2006. The overall suicide rate and the rate by firearms, poisoning, and other methods declined markedly, whereas the hanging/suffocation rate increased significantly from 1992 to 2006. This increase occurred across every major demographic subgroup, but was most dramatic for females.  相似文献   
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IntroductionInterprofessional learning (IPL) is a vital aspect of training in radiation oncology professions, yet is rarely delivered to those professionals who work most closely together in clinical practice. Scenario-based learning using simulation facilities provides a unique opportunity to facilitate this learning and this project aimed to determine the impact and value of this initiative.MethodsSmall groups comprising post-graduate diploma pre-registration therapeutic radiographers, medical physics trainees and radiation oncology registrars were challenged with 4 plausible and challenging radiotherapy scenarios within an academic simulation centre. Pre- and post-event completion of the “Readiness for Interprofessional Learning Scale” measured impact and a Likert-style survey gathered feedback from participants.ResultsThe session increased participants' teamwork and collaboration skills as well as strengthening professional identities. Participants reported high levels of enjoyment related to collaborative working, communication and observing other professionals deploying their technical skills and specialist knowledge.ConclusionAlthough beneficial, simulated scenarios offering equal opportunities for engagement across the professions are challenging to plan and timetabling issues between the 3 groups present significant difficulties. The safe environment and unique opportunity for these groups to learn together was particularly well received and future oncology-specific simulated scenario sessions are planned with larger cohorts.Implications for practiceSimulated scenario training can be used to improve team working across the radiotherapy interprofessional team and may have wider use in other specialist interdisciplinary team development.  相似文献   
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A prospective evaluation of color flow mapping and real-time ultrasound was performed to determine if pseudoaneurysms could be distinguished from other causes of masses surrounding vascular grafts of the lower extremities. Twelve palpable pulsatile masses were imaged. Diagnoses were confirmed at angiography (n = 11), computed tomography (n = 7), aspiration biopsy (n = 5), and operative intervention (n = 6). A swirling pattern of blood flow was seen in six of seven cases of pseudoaneurysm. Lack of flow signals was noted in four of the five collections representing hematoma (n = 2) or infection (n = 2). The seventh case was later shown to be an infected, thrombosed pseudoaneurysm. The single false-positive diagnosis was made early in the series when the flow signals detected were due to transmitted arterial pulsations. The authors conclude that color Doppler flow imaging is useful in the differential diagnosis of pulsatile masses associated with prosthetic grafts. Prosthetic graft pseudoaneurysms have a specific appearance of swirling blood flow arising from a wide neck and are distinguishable from traumatic or iatrogenic pseudoaneurysms of the native vascular tree.  相似文献   
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