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BACKGROUND: Hypomania/mania and depression are hypothesized to correspond to high and low expressions of behavioral activation system (BAS) activity, respectively, in bipolar individuals. In contrast, behavioral inhibition system (BIS) activity is hypothesized to regulate anxiety. The aim of the present study was to examine whether self-reported levels of BAS functioning in bipolar adolescents corresponded with levels of concurrent manic and depressive symptomatology. The secondary aim was to investigate whether self-reported BIS levels were associated with self-reported anxiety symptoms. METHODS: Twenty-five adolescents diagnosed with bipolar I, II or not otherwise specified were recruited from a treatment-development study. Adolescents were interviewed using the Depression and Mania Rating Scales of the Kiddie Schedule for Affective Disorders and Schizophrenia and given the Self-Report for Childhood Anxiety Related Disorders. Next, they completed the Behavioral Inhibition/Activation Scales. RESULTS: Contrary to hypotheses, adolescents with higher BAS levels exhibited less severe concurrent mania symptoms. Furthermore, levels of BAS sensitivity were not associated with concurrent levels of depression. As predicted, BIS scores correlated positively with self-reported anxiety scores. Adolescents reporting higher levels of the motor activity symptoms of mania also reported higher levels of anxiety symptoms. LIMITATIONS: The conclusions are based upon cross-sectional analyses in a small sample. CONCLUSIONS: In bipolar adolescents, mania and depression appear to be independent of self-reported behavioral activation levels. However, mood symptoms in adolescent patients are closely tied to components of anxiety, which may lead to diminished approach behaviors.  相似文献   
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Allocation policies are necessary to ensure a fair distribution of a scarce resource. The goal of any liver transplant allocation policy is to achieve the best possible outcomes for the waiting list population, irrespective of the indication for transplant, whilst maximizing organ utilization. Organ allocation for liver transplantation has evolved from simple centre-based approaches driven by local issues, to complex, evidence-based algorithm prioritizing according to need. Despite the rapid evolution of allocation policies, there remain a number of challenges and new approaches are required to ensure transparency and equity on the decision-making process and the best possible outcomes for patients on the waiting list. New ways of modelling, together with novel outcome criteria, will be required to enable a dynamic adaptability of the allocation policies to the ever changing demographics of the donor population and the changing landscape of indications for transplantation.  相似文献   
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Objective

This study evaluated the effect of three metal conditioners on the shear bond strength (SBS) of a prosthetic composite material to cpTi grade I having three surface treatments.

Material and Methods

One hundred sixty eight rivet-shaped specimens (8.0x2.0 mm) were cast and subjected to polishing (P) or sandblasting with either 50 mm (50SB) or 250 mm (250SB) Al2O3. The metal conditioners Metal Photo Primer (MPP), Cesead II Opaque Primer (OP), Targis Link (TL), and one surface modification system Siloc (S), were applied to the specimen surfaces, which were covered with four 1-mm thick layers of resin composite. The resin layers were exposed to curing light for 90 s separately. Seven specimens from each experimental group were stored in water at 37ºC for 24 h while the other 7 specimens were subjected to 5,000 thermal cycles consisting of water baths at 4ºC and 60ºC (n=7). All specimens were subjected to SBS test (0.5 mm/min) until failure occurred, and further 28 specimens were analyzed using scanning electron microscope (SEM) and X-ray energy-dispersive spectroscopy (EDS). Data were analyzed by 3-way ANOVA followed by post-hoc Tukey''s test (α=0.05).

Results

On 50SB surfaces, OP groups showed higher SBS means than MPP (P<0.05), while no significant difference was found among OP, S, and TL groups. On 250SB surfaces, OP and TL groups exhibited higher SBS than MPP and S (P<0.05). No significant difference in SBS was found between OP and TL groups nor between MPP and S groups. The use of conditioners on 250SB surfaces resulted in higher SBS means than the use of the same products on 50SB surfaces (P<0.05).

Conclusion

Sandblasting associated with the use of metal conditioners improves SBS of resin composites to cpTi.  相似文献   
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Erythropoietin(EPO) is one of the most successful biopharmaceuticals in history and is used for treating anemia of different origins. However, it became clear that EPO could also work in a neuroprotective, antiapoptotic, antioxidative, angiogenetic and neurotropic way. It causes stimulation of cells to delay cell apoptosis, especially in the central nervous system. In rodent models of focal cerebral ischemia, EPO showed an impressive reduction of infarct size by 30% and improvement of neurobehavioral outcome by nearly 40%. A large animal model dealing with ischemia and reperfusion of the spinal cord showed that EPO could reduce the risk of spinal cord injury significantly. In addition, some clinical studies tested whether EPO works in real live clinical settings. One of the most promising studies showed the innocuousness and improvements in follow-up, outcome scales and in infarct size, of EPO-use in humans suffering from ischemic stroke. Another study ended unfortunately in a negative outcome and an increased overall death rate in the EPO group. The most possible reason was the involvement of patients undergoing simultaneously systemic thrombolysis with recombinant tissue plasminogen activator. An experimental study on rats demonstrated that administration of EPO might exacerbate tissue plasminogen activator-induced brain hemorrhage without reducing the ischemic brain damage. This case shows clearly how useful animal models can be to check negative side effects of a treatment before going into clinical trials. Other groups looked in human trials at the effects of EPO on the outcome after ischemic stroke, relation to circulating endothelial progenitor cells, aneurysmal subarachnoid hemorrhage, traumatic brain injury, hemoglobin transfusion thresholds and elective first-time coronary artery bypass surgery. Most of the results were positive, but are based mostly on small group sizes. However, some of the most neglected facts when focusing on experimental setups of ischemia of the central nervous system are issues like age and comorbidities. It might be extremely worthy to consider these points for future projects, because EPO might influence all these factors.  相似文献   
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The involuntary hospitalization law provides a means by which love ones, caregivers and healthcare professionals can intervene when a mentally ill patient is a danger to self or others. Our study assessed the knowledge of professionals in one of the Greenville Health System (GHS) emergency department (ED) about the involuntary hospitalization process of mental health patients in South Carolina (SC). An eight item survey on the South Carolina involuntary hospitalization and commitment process was developed and distributed to GHS ED staff including: physicians, physician assistants, nurse practitioners, nurses, social workers and technicians. Our findings indicated that the knowledge base is not consistent across healthcare discipline, nor is it sufficient given that most professionals achieved less than 50% correct response. This study has implications for ongoing education for ED healthcare workers which will be of significant importance to promote beneficence and to uphold the standards of patientcentered practice and compassionate medicine.  相似文献   
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The metabolic syndrome includes changes in blood glucose levels, arterial hypertension, triglycerides, dyslipidemia and central obesity. Countless reports have described the correlation between the metabolic syndrome and cognitive impairment. However, only a few reports have assessed cognitive impairment associated with the metabolic syndrome in animals of both sexes. For this purpose, Sprague‐Dawley male and female rats were fed either with a hypercaloric diet as model of the metabolic syndrome or with a standard chow diet as controls. Subsequently, spatial learning and memory (Morris water maze) as well as short‐ and long‐term memory (passive avoidance task) were evaluated. Body weight, blood pressure, triglycerides, and total cholesterol significantly increased (F(1, 36) = 94.89, p < .001) in rats fed with hypercaloric diet compared to control rats. Furthermore, cognitive impairment was observed in spatial learning and spatial memory on male rats but not on female rats fed with hypercaloric diet. In addition, a long‐term memory impairment was observed in both groups fed with hypercaloric diet in comparison to their respective control group (F(1, 32) = 10.61, p = .0027). Immunohistochemistry results showed no changes in the number of positive cells for NeuN, GFAP and Ox‐42. In males fed with a hypercaloric diet, a decrease in testosterone levels was observed, whereas estradiol levels decreased in females when compared with their respective control group (p < .0001). In this MetS animal model, metabolic and cognitive differences were observed in males and females, which demonstrates that sex hormones play a significant role in metabolic regulation and neuroprotection related to the CA1 region of the hippocampus.  相似文献   
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