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961.
Ayers S Zink DL Mohn K Powell JS Brown CM Murphy T Brand R Pretorius S Stevenson D Thompson D Singh SB 《Planta medica》2007,73(3):296-297
Two known aporphine alkaloids, (S)-dicentrine (1) and (S)-neolitsine (2), have been isolated from the MeOH extract of the aerial parts of Cissampelos capensis (Menispermaceae). The structures of these compounds were elucidated by NMR and MS analysis and comparison to literature data. These compounds were isolated by bioassay-guided fractionation using the Haemonchus contortus larval development assay. Compounds 1 and 2 exhibited EC90 values (concentration at which 90% loss of larval motility is observed) of 6.3 and 6.4 microg/mL, respectively. In an IN VIVO assay, administration of 1 resulted in 67% reduction of worm counts in mice at 25 mg/kg when dosed orally. 相似文献
962.
The descending control of dorsal fin posture by a reidentifiable reticulospinal command neuron (I1), was examined in the sea lamprey, Petromyzon marinus. Intracellular stimulation of I1 controls the posture of both dorsal fins. Spinal transection between the fins results not only in loss of control of posterior dorsal fin posture, but after 2 h, the control of the anterior dorsal fin as well. Anterior dorsal fin responses remained absent at 4, 5 and 6 days after transection. Stimulation of I1 could control anterior dorsal fin posture in specimens which had recovered the ability to right during swimming (77 and 100 days after transection), although higher than normal stimulus frequencies were required. I1 control of posterior dorsal fin posture did not recover. 相似文献
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Arianna Barnes Gordon Y. Ye Cadie Ayers Amanda Choflet Kelly C. Lee Sidney Zisook Judy E. Davidson 《Nursing inquiry》2023,30(2):e12537
Nurses die by suicide at a higher rate than the general population. Previous studies have observed mental health problems, including substance use, as a prominent antecedent before death. The purpose of this study was to explore the characteristics of nurses who died by suicide documented in the death investigation narratives from the National Violent Death Reporting System from 2003 to 2017 using thematic analysis and natural language processing. One thousand three hundred and fifty-eight subjects met these inclusion criteria. Narratives from 601 subjects were thematically analyzed and 2544 individual narratives were analyzed using natural language processing. The analyses revealed five themes: “mental health treatment,” “poor general health and chronic pain,” “substance use,” “worsening mental health after bereavement,” and “repeating a family member's suicide.” Mental health/substance use, chronic illness, and chronic pain were seen to coexist in a complex, interdependent manner that appeared to be entangled in the nurses' narratives before death. These findings echo the need for reducing the stigmatization of mental health problems in nursing and removing barriers to help-seeking behaviors as early preventative interventions. Future research is needed to determine if a comprehensive healthcare integration approach to address these entangled problems would reduce suicide vulnerability in nurses and improve their quality of life. 相似文献