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The World Health Organization has predicted that neurodegenerative diseases affecting the motor function will become the second most prevalent cause of death in the next 20 years.New therapies can result from three main sources:synthetic compounds,natural products,and existing drugs.Parkinson’s disease(PD)is a common neurodegenerative disease affecting 1–3%of the adult population over 50 years of age worldwide.It is initially characterized by the death of dopaminergic neurons in the substantia nigra pars compact and later by the widespread loss of nondopaminergic neurons,including those in the cortex.  相似文献   
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Objective

Research on proximal fractures in the humeral bicipital groove (BG), a region in which bones are not commonly fractured, is considered sparse in the literature. The objective of this research was to present the definite characteristics and distribution of BG fractures.

Methods

This retrospective study included and enrolled 119 proximal humeral fractures in adult patients with complete radiography data to identify the fracture distribution in the BG from January 2021 to August 2021. The bicipital region was divided into three parts, i.e. the upper 1/3, middle 1/3, and lower 1/3 of the BG, and the distribution of fracture lines was transcribed on the male or female template, as appropriate. In addition, the normal contralateral humerus was used to calculate the cortical thickness of the supratubercular groove and different parts of the BG (upper, middle, and lower parts). The Mann–Whitney test or one-way ANOVA along with LSD tests were used to determine differences in the fracture distribution and cortical thickness between men and women.

Results

Fractures of the BG in both men and women were mainly located in the upper 2/3 region of the BG, especially in the middle 1/3 of the BG. There were significant differences in the cortical thickness of the BG in men compared with that in women. The cortical thickness was highest in the supratubercular ridge but not the BG in men and women, respectively.

Conclusion

This research concluded that bony BG fractures were always observed in the middle part of the BG and were mainly found in patients with four fractures of the proximal humerus. As a unique fracture pattern, the existence of a bony BG fracture always means that a patient has been injured by a relatively severe mechanism, and more attention should be given to these proximal humeral fractures.  相似文献   
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Introduction

It is unknown whether the treatment disparity observed between young and elderly women extends to the management of positive margins after initial lumpectomy. The primary aim was to evaluate the management of positive margins after initial lumpectomy in elderly women.

Methods

Women ≥50 y who underwent lumpectomy for stage I–III tumors were identified. Tumor and treatment characteristics were collected across two subgroups: young (50–69 y) and elderly (≥70 y). Univariate comparisons were done using chi-square and Wilcoxon Rank Sum test. A multivariable logistic regression was used to evaluate factors associated with reoperation. Incidence of overall recurrence was compared between young and elderly women by plotting the cumulative incidence function of overall recurrence and death without recurrence.

Results

Of 1670 women identified, 29.5% were elderly. Compared to young women, tumors in elderly patients were more frequently invasive lobular carcinoma, larger, low grade and lymphovascular negative. Positive margins were less common in elderly than young women (10.8% versus 16.2%, unadjusted OR 0.60, 95% CI 0.42–0.86). Compared to young women, elderly women were less likely to undergo reoperation (84.9% versus 100%, p < 0.001), adjuvant chemotherapy (5.7% versus 46.6%, p < 0.0001), and adjuvant radiation therapy (69.8% versus 83.9%, p = 0.04). Five-year disease free survival (DFS) was similar between age groups (86% versus 86%, p = 0.8).

Conclusions

Elderly women with positive margins after initial lumpectomy were treated differently than younger women as shown by a lower rate of reoperation and adjuvant radiation therapy. Despite these treatment variations there was no impact on overall recurrence and DFS.  相似文献   
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Chronic rejection accounts for most renal allograft losses after the first year posttransplantation. On March 24 and 25, 1997, a roundtable of five transplant surgeons, two nephrologists, and one pathologist assembled in Dallas, Texas, to review critical issues surrounding chronic renal allograft rejection. This article summarizes the presentations and relevant discussions of this meeting regarding the cause of chronic rejection, clinical diagnoses, risk factors, future prospects for intervention strategies, and general recommendations for the transplant community. Growing evidence indicates that chronic rejection is the aggregate sum of irreversible immunologic and nonimmunologic injuries to the renal graft over time. A history of acute rejection episodes and inadequate immunosuppression, likely attributable to inconsistent cyclosporine exposure or poor patient compliance, are among the most recognizable immunologic risk factors for chronic rejection. Donor organ quality, delayed graft function, and other donor and recipient variables leading to reduced nephron mass are nonimmunologic factors that contribute to the progressive deterioration of renal graft function. Clinical management of renal transplant recipients should incorporate both immunologic- and nonimmunologic-based intervention strategies aimed at minimizing risk factors to thwart the progression of chronic rejection and improve long-term allograft and patient survival.  相似文献   
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