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An improved gradient, reversed-phase liquid chromatographic (RP-LC) method was developed and subsequently validated for the determination of Loratadine and its impurities/degradation products in pharmaceutical drug substance. Separation was achieved with Inertsil ODS-3V, 250 × 4.6 mm, 5μ column with gradient elution at a flow rate of 1.0 mL min(-1). UV detection was performed at 220 nm. The described method is linear over a range of LOQ (0.044, 0.088, 0.084, and 0.072 μg mL(-1) for impurity-B, impurity-C, impurity-D, and impurity-E respectively) to 1.2 μg mL(-1) (0.6 μg mL(-1) of the specification limit) for all the impurities and degradation products. The recovery of impurities were found to be in the range of 85-115 %. The method is simple, selective, and accurate for the quantification of impurities and degradation products of Loratadine in its bulk drug samples.  相似文献   
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A novel approach was used to develop and validate a rapid, specific, accurate and precise reverse phase ultra performance liquid chromatographic (UPLC) method for the simultaneous determination of Sitagliptin phosphate monohydrate and Metformin hydrochloride in pharmaceutical dosage forms. The chromatographic separation was achieved on Aquity UPLC BEH C8 100 × 2.1 mm, 1.7 μm, column using a buffer consisting of 10 mM potassium dihydrogen phosphate and 2 mM hexane-1-sulfonic acid sodium salt (pH adjusted to 5.50 with diluted phosphoric acid) and acetonitrile as organic solvent in a gradient program. The flow rate was 0.2 mL min(-1) and the detection wavelength was 210 nm. The limit of detection (LOD) for Sitagliptin phosphate monohydrate and Metformin hydrochloride was 0.2 and 0.06 μg mL(-1), respectively. The limit of quantification (LOQ) for Sitagliptin phosphate monohydrate and Metformin hydrochloride was 0.7 and 0.2 μg mL(-1), respectively. This method was validated with respect to linearity, accuracy, precision, specificity and robustness. The method was also found to be stability-indicating.  相似文献   
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Stress-vulnerability models of schizophrenia regard psychosocial stress as an important factor in the onset and aggravation of psychotic symptoms, but such research in the early phases of psychosis is limited. Protective factors against the effects of stress might be the key to understanding some inconclusive findings and to the development of optimal psychosocial interventions. The present study compared self-reported levels of stress, self-esteem, social support and active coping in 32 patients with a first episode of psychosis (FEP), 30 individuals at ultra-high risk for psychosis (UHR) and 30 healthy controls. Associations with symptoms of psychosis were assessed in both patient groups. Individuals at UHR reported significantly higher stress levels compared to FEP patients. Both patient groups showed lower self-esteem compared to controls, and the UHR group reported lower social support and active coping than controls. These group differences could not be explained by age and dose of antipsychotic medication in the FEP group. In the UHR group, higher stress levels and lower self-esteem were associated with more severe positive and depressive symptoms on the Brief Psychiatric Rating Scale. Multiple regression analyses revealed that stress was the only significant predictor for both symptom measures and that the relationship was not moderated by self-esteem. Our findings show that individuals at UHR for psychosis experience high levels of psychosocial stress and marked deficits in protective factors. The results suggest that psychosocial interventions targeted at reducing stress levels and improving resilience in this population may be beneficial in improving outcomes.  相似文献   
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This is a retrospective review to determine demographics, presentation and injury characteristics of trauma deaths at Howard University Hospital over an 1-year period (1994-2005) and to make recommendations for education and prevention in the community based on our findings. Data was obtained from the Howard University Hospital trauma registry. From the study period 1994-2005, there was a total of 365 trauma deaths. The injuries sustained were mainly intentional, which accounted for almost 75% of cases--the majority of deaths being due to penetrating injuries. There was an almost two-fold increase in trauma deaths on Saturdays compared to the rest of the week. The demographics of our study population were similar to those reported in the trauma literature. These were younger patients and predominantly male. Unique to our population was the overwhelming predominance of African-American patients (90%). With these unique features, injury prevention would be better served focusing on social and community prevention and education rather than the usual methods of blunt-trauma prevention--e.g., pedestrian- and motor-vehicle-oriented policies, which may be more beneficial in other trauma systems.  相似文献   
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