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51.

Background

Male breast cancer (MBC) is uncommon. As a result, there is limited availability of studies and reviews and even fewer reports from Asia. This is the largest population-based study to compare Chinese MBC patients with female patients during a 10-year period in Hong Kong, Southern China.

Methods

A retrospective review of medical records of 132 male and 8,118 female breast cancer patients between year 1997 and 2006 in Hong Kong was performed. Each MBC patient was matched with three female breast cancer patients for further analysis. Different characteristics, overall, breast-cancer specific, and disease-free survivals (DFS) were compared.

Results

Mean age at diagnosis of male and female patients was 64.5 and 52.7 years respectively. Male patients showed lower histological grade, overall stage, smaller tumor size, and more positive sensitivity in hormone receptors. They were more likely to die of causes other than breast cancer. Matched analysis found that the 5-year overall survival (OS), breast-cancer–specific mortality, and DFS for male and female patients were 78.7, 90.5, 90.5, and 77.9, 86.4, and 81.4 % respectively. Male patients had poorer OS at early overall stage but better breast-cancer—specific mortality rates at any age (p < 0.01). Male patients had a significant risk of dying due to any cause in the presence of distant relapse and had less risk of dying when tumor was ER-positive and HER2-positive.

Conclusions

Chinese male breast cancer patients tend to have poorer OS but better breast-cancer—specific survival compared with their female counterparts.  相似文献   
52.

Purpose:

The purpose of this study was to compare the total hospital costs associated with elective laparoscopic and open inguinal herniorrhaphy.

Methods:

A prospectively maintained database was used to identify patients who underwent elective inguinal herniorrhaphy from April 2009 to March 2011. A retrospective review of electronic patient records was performed along with a standardized case-costing analysis using data from the Ontario Case Costing Initiative. The main outcomes were operating room (OR) and total hospital costs.

Results:

Two hundred eleven patients underwent elective unilateral inguinal herniorrhaphy (117 open and 94 laparoscopic), and 33 patients underwent elective bilateral inguinal herniorrhaphy (9 open and 24 laparoscopic). OR and total hospital costs for open unilateral inguinal hernia repair were significantly lower than for the laparoscopic approach (median total cost, $3207.15 vs $3723.66; P < .001). OR and total hospital costs for repair of elective bilateral inguinal hernias were similar between the open and laparoscopic approaches (median total cost, $4574.02 vs $4662.89; P = .827).

Conclusions:

In the setting of a Canadian academic hospital, when considering the repair of an elective unilateral inguinal hernia, the OR and total hospital costs of open surgery were significantly lower than for the laparoscopic techniques. There was no statistical difference between OR and total hospital costs when comparing open surgery and laparoscopic techniques for the repair of bilateral inguinal hernias. Given the perioperative benefits of laparoscopy, further studies incorporating hernia-specific outcomes are necessary to determine the cost-effectiveness of each approach and to define the optimal treatment strategy.  相似文献   
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Objective: To evaluate the potential of Gracilaria changii extract in ameliorating the potential adverse effects of bisphenol A. Methods: The antioxidant capacity of Gracilaria changii extracted using different solvents(methanol, ethanol, and aqueous) was studied. The mice were administered by oral gavage with bisphenol A(60 mg/kg body weight) for 6 weeks with or without Gracilaria changii aqueous extract. Thereafter, the mice were either euthanized for histology and immunohistochemistry studies or mated to evaluate the pregnancy rate. Results: Gracilaria changii aqueous extract showed the highest antioxidant properties compared with extract using methanol and ethanol. The aqueous extract of Gracilaria changii improved the uterus index and uterine lipid peroxidation after bisphenol A exposure, although the uterine expressions of estrogen receptors and complement C3 were not improved. Histological evaluation of the uterus during the estrus stage has revealed that the extract could mitigate bisphenol A-induced adverse effects in the uterus as there was a lower percentage of mice showing abnormalities like decreased eosin staining in the myometrium, and decrease in the number of eosinophil and endometrial glands in the endometrium. Besides, Gracilaria changii aqueous extract improved the pregnancy rate of mice administered with bisphenol A. Conclusions: Gracilaria changii extract protects against bisphenol A-induced female reproductive abnormalities in mice which may be mediated via modulation of eosinophil migration, endometrial gland formation, and protein expressions associated with prostaglandins in the myometrium.  相似文献   
56.
ObjectivesAlthough pertussis vaccines have been widely used for many decades, a burden of illness persists. Resurgences in Ontario, Canada, have not been substantial in the past decade, but an outbreak of pertussis occurred in Toronto between 1 October 2005 and 31 March 2006. Previous Ontario studies found high vaccine effectiveness (VE) in the initial years post-immunization. In order to explore the impact of outbreaks and external factors on VE, we investigated pertussis VE during the period 2006–2008.MethodsWe assessed pertussis VE using a frequency-matched case-control study for the period 1 March 2006 to 31 December 2008. We used logistic regression to estimate VE by age, time since last vaccination, and vaccination status according to the Ontario recommended schedule. We compared analyses including and excluding cases from Toronto, and to two recent Ontario pertussis VE studies.ResultsWe included 1797 confirmed cases and 7188 matched controls. Most cases were under 4 years of age during the study period. Pertussis VE was 3.8% (95% CI: − 21.0, 24.0) in the period 15–364 days following the last pertussis vaccine dose, and increased with increasing time since vaccination. Pertussis VE in the first 15–364 days excluding Toronto increased to 57.1% (95% CI: 26.0, 75.1), but the trend of increasing VE with time since vaccination persisted. Although VE was higher in older (6–11 years) than younger (0–5 years) children, it was lower at 12–13 years than after 14 years.ConclusionVE was lower in comparison with other studies conducted in Ontario, particularly in younger children. Various factors occurring during the study period may have influenced the results, including clinical testing of asymptomatic contacts, laboratory testing and methods and reporting practice, and a sensitive case definition. Further studies are needed to optimize methods for measuring VE to inform pertussis vaccine policy.  相似文献   
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Amblyopia, sometimes called "lazy eye," is a relatively common developmental visual disorder well characterized behaviorally; however, the neural substrates associated with amblyopia in humans remain unclear. We hypothesized that abnormalities in the cerebral cortex of subjects with amblyopia exist, possibly as a result of experience-dependent neuronal plasticity. Anatomic magnetic resonance imaging (MRI) and psychophysical vision testing was carried out on 74 subjects divided into two age ranges, 7-12 years and 18-35 years, and three diagnoses, strabismic amblyopia, anisometropic amblyopia, and normal vision. We report a behavioral impairment in contrast sensitivity for subjects with amblyopia, consistent with previous reports. When the high-resolution MRI brain images were analyzed quantitatively with optimized voxel-based morphometry, results indicated that adults and children with amblyopia have decreased gray matter volume in visual cortical regions, including the calcarine sulcus, known to contain primary visual cortex. This finding was confirmed with a separate region-of-interest analysis. For the children with amblyopia, additional gray matter reductions in parietal-occipital areas and ventral temporal cortex were detected, consistent with recent reports that amblyopia can result in spatial location and object processing deficits. These data are the first to provide possible neuroanatomic bases for the loss of binocularity and visual sensitivity in children and adults with amblyopia.  相似文献   
59.
Cheung LK  Zheng LW 《The Journal of craniofacial surgery》2006,17(1):100-8; discussion 109-10
This study evaluates the effect of recombinant human (rh) bone morphogenetic protein (BMP)-2 on mandibular distraction at normal and rapid distraction rates. This study also determines the feasibility of compensating for the increased distraction rate by the addition of rhBMP-2 while maintaining the quality of the distraction regenerate. Twenty-four New Zealand white rabbits were divided into 2 groups, 1 treated at a normal distraction rate (0.9 mm/d) and the other at a rapid distraction rate (2.7 mm/d). At the end of the active distraction period, rhBMP-2 was injected into distraction regenerate, and the contralateral side was used as a control. The distraction regenerates were analyzed by plain radiography, microcomputed tomography, and mechanical testing. The results showed that rhBMP-2 can promote bone formation at both rapid and normal distraction rates. At week 2 and week 4 of consolidation, bone volumes in the BMP-injection sides were significantly higher than in the control sides, but no statistically significant difference was observed between the BMP-injection sides of the rapid and normal distraction groups. At week 8 of consolidation, mechanical testing demonstrated no significant difference of the failure load and stiffness between the BMP-injection and control sides. In conclusion, the study indicates that rhBMP-2 can enhance bone ossification at both normal and rapid distraction rates. The addition of rhBMP-2 can compensate for the rapid distraction rate in mandibular distraction osteogenesis. However, in the long term, the bone quality and stiffness of the distraction regeneration was not influenced by rhBMP-2.  相似文献   
60.
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