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Pharmacological studies of antidepressants and atypical antipsychotics have suggested a role of dopamine and serotonin signaling in depression. However, depressive symptoms and treatment effects are difficult to explain based simply on brain‐wide decrease or increase in the concentrations of these molecules. Recent animal studies using advanced neuronal manipulation and observation techniques have revealed detailed dopamine and serotonin dynamics that regulate diverse aspects of motivation‐related behavior. Dopamine and serotonin transiently modulate moment‐to‐moment behavior at timescales ranging from sub‐second to minutes and also produce persistent effects, such as reward‐related learning and stress responses that last longer than several days. Transient and sustained effects often exhibit specific roles depending on the projection sites, where distinct synaptic and cellular mechanisms are required to process the neurotransmitters for each transient and sustained timescale. Therefore, it appears that specific aspects of motivation‐related behavior are regulated by distinct synaptic and cellular mechanisms in specific brain regions that underlie the transient and sustained effects of dopamine and serotonin signaling. Recent clinical studies have implied that subjects with depressive symptoms show impaired transient and sustained signaling functions; moreover, they exhibit heterogeneity in depressive symptoms and neuronal dysfunction. Depressive symptoms may be explained by the dysfunction of each transient and sustained signaling mechanism, and distinct patterns of impairment in the relevant mechanisms may explain the heterogeneity of symptoms. Thus, detailed understanding of dopamine and serotonin signaling may provide new insight into depressive symptoms.  相似文献   
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Background: Few new Residency Program Directors (PD) are formally trained for the demands and responsibilities of the leadership aspect of their role. Currently, there are no comprehensive frameworks that describe specific leadership competencies that can inform PD self-reflection or faculty development.

Methods: The authors developed a Postgraduate Program Director Competency Inventory (PPDCI) in order to frame the performance of PDs for a multisource feedback (MSF) program. The development of the PPDCI occurred in five phases which involved: development of an initial inventory, implementation of a key informant survey of national opinion leaders, execution of a validity survey with postgraduate education leaders and committee members and implementation of a further refined inventory with 17 PD and 147 raters as part of a pilot MSF program.

Outcomes: Five distinct domains of leadership competence were identified which included: Communication and relationship management, leadership, professionalism and self-management, environmental engagement, and management skills and knowledge. The content validity of the PPDCI was endorsed by 85% of the key informants. The validity survey indicated strong endorsement of the PPDCI domains and recognition of its utility for both orientation of new PD as well as a frame for self-assessment. The pilot MSF program yielded a further refined and reduced inventory of 26 items of competence as well as recommendations for its utility.

Conclusions: Use of this leadership inventory has the potential to ensure effective leadership of postgraduate programs.  相似文献   
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Pediatric Surgery International - The programmed death 1 (PD-1)/programmed death ligand 1 (PD-L1) pathway has garnered much attention for its roles in clinical oncology. The aim of this study was...  相似文献   
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We report a case of a diaphragmatic hernia after a heart transplant operation. A 43-year-old woman, who underwent orthotropic heart transplantation for hypertrophic cadiomyopathy two year earlier, presented with vomiting and epigastric pain. A computed tomography scan showed that the stomach and transverse colon were dislocated in the left thoracic cavity. We diagnosed left diaphragmatic hernia incarceration and performed laparoscopic repair of the diaphragmatic hernia. A 12 × 8 cm diaphragmatic defect was found intraoperatively on the ventrolateral aspect of the left diaphragm, and the stomach with volvulus had herniated into the thorax through the defect. The hernia was considered to be iatrogenic. The diaphragmatic defect was large, and the diaphragm was thinning. We closed the defect by mesh repair. Laparoscopic mesh repair of the diaphragmatic hernia could be performed safely and with minimal invasiveness.  相似文献   
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Kohmoto  Tomohiro  Masuda  Kiyoshi  Shoda  Katsutoshi  Takahashi  Rizu  Ujiro  Sae  Tange  Shoichiro  Ichikawa  Daisuke  Otsuji  Eigo  Imoto  Issei 《Gastric cancer》2020,23(3):403-417
Gastric Cancer - We aimed to identify novel tumor-promoting drivers highly expressed in gastric cancer (GC) that contribute to worsened prognosis in affected patients. Genes whose expression was...  相似文献   
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