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61.
Abstract

Pulmonary blastoma (PB) is an uncommon primary lung malignancy. This neoplasm was first described by Barrett and Barnard in 1945. The tumor is composed of immature epithelial and mesenchymal tissues which may recapitulate early embryological lung development. Under the microscope, the globular component resembles immature bronchus and connective tissue as seen in embryonic lung. More than one hundred cases have been reported in the literature. PB is more frequent in older people and in males and tends to affect blacks at younger ages. Symptomatology varies from asymptomatic to symptoms of a non-specific pulmonary disease. Cough, hemoptysis, dyspnea, chest pain, respiratory distress, fever, anorexia and weight loss are the most common presenting features. The most common roentgenologic pattern is a well-demarcated peripheral lesion, encapsulated by compression or atelectatic lung tissue, although in some cases there is a tendency to lobulation and cavitation. The size of the mass varies from a small peripheral nodule to a mass occupying the entire lobe or hemithorax. The treatment of choice has been surgical excision, radiation and, in selected cases, a combination of chemotherapy with radiation. The prognosis of this malignancy is poor; overall five-year survival is approximately 16 percent. No correlation has been established between histopathologic criteria and survival. The factors that indicate poor prognosis are tumor recurrence, metastasis at initial presentation, tumor size over 5 cm and lymph node metastasis. Liver, central nervous system and bones are the most frequent location of distant metastases. A rare case is presented of a pulmonary blastoma with an upper lip metastasis occurring in a paraplegic male. Diagnosis was confirmed by autopsy findings. To our knowledge, this is the first documented case of a pulmonary blastoma metastasis to the upper lip. (J Spinal Cord Med; 18:203–207)  相似文献   
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Introduction: CD8+ T lymphocytes (CD8TLs) express β-adrenergic receptors (βAR), which bind the neurotransmitter norepinephrine and stress hormone epinephrine released during inflammation, trauma, and psychological stress. Little is known about the functions of this βAR expression on CD8TLs. Methods: Volunteers were exposed to a psychological stressor (N=24). Flow cytometry identified CD8TL subsets by CCR7, CD27, CD28 and CD45RA expression. Adrenergic receptor subtype expression was determined by micro-array. The effects of βPAR stimulation on IFN-γ production in activated CD8TLs was tested in vitro using PMA/Ionomycin. Results: Stress caused selective migration of effector-memory (CCR7CD27CD28) CD8TLs into the blood (+148%, p<.001). An 8-fold up-regulation of the β2AR was demonstrated in effector-memory cells as compared to naïve CD8TLs. Stimulation of the β2AR subtype completely inhibited IFN-γ production. Conclusion: These results show that β2AR stimulation enhances peripheral immune surveillance in a highly selective manner, and might protect against excessive cytokine release during inflammation and stress.

  相似文献   
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The prognosis of the association between Breast Cancer (BC) and Meningioma (M) is unknown. To evaluate the survival impact of tumor exposure sequence in patients with both tumors. Patients were divided in groups according to the tumors sequence: BC before M (group 1), synchronous BC?+?M (group 2) and BC after M (group 3). The SEER database was used. Demographics, meningioma and breast cancer variables were analyzed. The primary outcome was oncological survival. A total of 1715 patients were included (median follow-up:84 months). Group 2 had the shortest survival (median:32 months) and group 1 the longest (median:110 months). On the unadjusted analysis, group 2 had the shortest survival (HR:3.13, 95% CI 1.62–6.04) and adjusted analysis confirmed this finding (HR 3.11, 95% CI 1.58–6.19), with no statistical difference between the metachronous tumors groups. Increasing age (HR:1.13, 95% CI 1.11–1.15, p?<?0.005) and grade III meningioma (HR:4.51, 95% CI 1.90–10.69, p?<?0.005) were related with lower survival. Meningioma treatment had no influence on the survival (p?>?0.05). The association between surgery and radiotherapy in BC treatment improved the outcome (HR 0.37, 95% CI 0.23–0.93, p?<?0.05). Grade III meningioma and receptor hormonal status influenced synchronous tumors (p?<?0.05) but had no influence on metachronous tumors survival (p?>?0.05) on stratified analysis. Synchronous tumors were associated with lower survival. Increasing age had a negative influence on patient survival. Although surgery and radiotherapy for breast cancer had a positive influence in the outcome, meningioma treatment was not related with survival. Grade III meningioma and hormonal receptor status only influenced synchronous tumors patient survival.  相似文献   
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Objective

To evaluate whether Medicare's Hospital Readmissions Reduction Program (HRRP) is associated with increased observation stay use.

Data Sources and Study Setting

A nationally representative sample of fee-for-service Medicare claims, January 2009–September 2016.

Study Design

Using a difference-in-difference (DID) design, we modeled changes in observation stays as a proportion of total hospitalizations, separately comparing the initial (acute myocardial infarction, pneumonia, heart failure) and subsequent (chronic obstructive pulmonary disease) target conditions with a control group of nontarget conditions. Each model used 3 time periods: baseline (15 months before program announcement), an intervening period between announcement and implementation, and a 2-year post-implementation period, with specific dates defined by HRRP policies.

Data Collection/Extraction Methods

We derived a 20% random sample of all hospitalizations for beneficiaries continuously enrolled for 12 months before hospitalization (N = 7,162,189).

Principal Findings

Observation stays increased similarly for the initial HRRP target and nontarget conditions in the intervening period (0.01% points per month [95% CI −0.01, 0.3]). Post-implementation, observation stays increased significantly more for target versus nontarget conditions, but the difference is quite small (0.02% points per month [95% CI 0.002, 0.04]). Results for the COPD analysis were statistically insignificant in both policy periods.

Conclusions

The increase in observation stays is likely due to other factors, including audit activity and clinical advances.  相似文献   
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