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PurposeTumor size and lymph node metastasis are important factors that contribute to the progression of breast cancer. We aimed to analyze the relationship between tumor size and lymph node metastasis molecular subtype and examine the effects of nodal metastasis on overall survival (OS).MethodsWe retrospectively reviewed the data of 16,552 patients who underwent breast surgery in Samsung Medical Center between 2000 and 2015. Information on tumor size (largest diameter of the invasive component), number of positive lymph nodes, and molecular subtype were obtained. We constructed a linear regression model to evaluate the relationship between tumor size and lymph node metastasis. To determine the effect of nodal metastasis on OS, we performed a Cox proportional regression analysis with Np/T (number of metastatic lymph nodes [n]/tumor size [cm]).ResultsThis study included 12,007 patients with a median follow-up of 62 months. The linear regression coefficients were 1.043 for luminal A, 1.024 for luminal B, 0.656 for HER2, and 0.435 for triple-negative breast cancer (TNBC) subtypes. No significant difference was observed in the coefficients between the luminal A and B subtypes (p = 0.797), while all other coefficients showed significant difference. After adjusting for other risk factors, the hazard ratio (HR) of Np/T for each subtype was significant for OS: luminal A (HR, 1.134; 95% confidence interval [CI], 1.097–1.171; p < 0.001), luminal B (HR, 1.049; 95% CI, 1.013–1.086; p = 0.007), HER2 (HR, 1.069; 95% CI, 1.014–1.126; p = 0.013), and TNBC (HR, 1.038; 95% CI, 1.01–1.067; p = 0.008).ConclusionThe incidence of lymph node metastasis differed according to molecular subtype. Luminal types have higher incidence of nodal metastasis than HER2 and TNBC. The HR of Np/T was highest in luminal A subtypes and lowest in TNBC subtypes.  相似文献   
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Objective

Large reductions in inpatient length of stay and inpatient bed supply have occurred across health systems in recent years. However, the direction of causation between length of stay and bed supply is often overlooked. This study examines the impact of changes to inpatient bed supply, as a result of recession-induced healthcare expenditure changes, on emergency inpatient length of stay in Ireland between 2010 and 2015.

Study design

We analyse all public hospital emergency inpatient discharges in Ireland from 2010 to 2015 using the administrative Hospital In-Patient Enquiry dataset. We use changes to inpatient bed supply across hospitals over time to examine the impact of bed supply on length of stay. Linear, negative binomial, and hospital–month-level fixed effects models are estimated.

Results

U-shaped trends are observed for both average length of stay and inpatient bed supply between 2010 and 2015. A consistently large positive relationship is found between bed supply and length of stay across all regression analyses. Between 2010 and 2012 while length of stay fell by 6.4%, our analyses estimate that approximately 42% (2.7% points) of this reduction was associated with declines in bed supply.

Conclusion

Changes in emergency inpatient length of stay in Ireland between 2010 and 2015 were closely related to changes in bed supply during those years. The use of length of stay as an efficiency measure should be understood in the contextual basis of other health system changes. Lower length of stay may be indicative of the lack of resources or available bed supply as opposed to reduced demand for care or the shifting of care to other settings.

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Aim of the study: Parkinson’s disease (PD) is a neurodegenerative disorder. It is caused by the degeneration of dopaminergic neurons and the dopamine (DA) deletion in the substantia nigra pars compacta (SNpc). Morphine elevates the level of dopamine in the mesolimbic dopamine system and plays a role in alleviating PD symptoms. However, the molecular mechanism is still unclear. The aim of the study is to investigate the mechanism on morphine alleviating PD symptoms.

Materials and methods: The viability of PC12 cells was measured by using MTT assay. The expressions of tyrosine hydroxylase (TH), thioredoxin-1 (Trx-1), CyclinD1 and Cyclin-dependent kinase5 (Cdk5) were detected by Western Blot.

Results: In present study, we found that morphine increased the cell viability in PC12 cells. 1-methyl-4-phenylpyridi-nium (MPP+) reduced the cell viability and TH expression, which were reversed by morphine. MPP+ decreased the expressions of Trx-1, CyclinD1, Cdk5, which were restored by morphine. Moreover, the role of morphine in restoring the expressions of Trx-1, CyclinD1 and Cdk5 decreased by MPP+ was abolished by LY294002, phosphatidylinositol-3-kinase (PI3K)/Akt inhibitor.

Conclusions: These results suggest that morphine reverses effects induced by MPP þ through activating PI3K/Akt pathway.  相似文献   

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Objective The objective of the present study was to explore causal pathways to understand how second traumatic experiences could affect the development of emotional exhaustion and psychiatric problems. Methods A total of 582 workers who had jobs vulnerable to secondary traumatic experiences were enrolled for this study. Emotional exhaustion, secondary trauma, resilience, perceived stress, depression, anxiety, and sleep problems were evaluated. A model with pathways from secondary traumatic experience score to depression and anxiety was proposed. The participants were divided into three groups according to the resilience: the low, middle and high resilience group. Results Resilience was a meaningful moderator between secondary traumatic experiences and psychiatric problems. In the path model, the secondary trauma and perceived stress directly and indirectly predicted perceived stress, emotional exhaustion, depression, anxiety, and sleep problems in all three groups. Direct effects of perceived stress on depression and anxiety were the largest in the low resilience group. However, direct effects of secondary trauma on perceived stress and emotional exhaustion were the largest in the high resilience group. Conclusion Understanding the needs of focusing for distinct psychological factors offers a valuable direction for the development of intervention programs to prevent emotional exhaustion among workers with secondary traumatic experiences.  相似文献   
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