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We present a case report on visual brain plasticity after total blindness acquired in adulthood. SH lost her sight when she was 27. Despite having been totally blind for 43 years, she reported to strongly rely on her vivid visual imagery. Three-Tesla magnetic resonance imaging (MRI) of SH and age-matched controls was performed. The MRI sequence included anatomical MRI, resting-state functional MRI, and task-related functional MRI where SH was instructed to imagine colours, faces, and motion. Compared to controls, voxel-based analysis revealed white matter loss along SH’s visual pathway as well as grey matter atrophy in the calcarine sulci. Yet we demonstrated activation in visual areas, including V1, using functional MRI. Of the four identified visual resting-state networks, none showed alterations in spatial extent; hence, SH’s preserved visual imagery seems to be mediated by intrinsic brain networks of normal extent. Time courses of two of these networks showed increased correlation with that of the inferior posterior default mode network, which may reflect adaptive changes supporting SH’s strong internal visual representations. Overall, our findings demonstrate that conscious visual experience is possible even after years of absence of extrinsic input.  相似文献   
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Interpretation of data illustrating that estrogen, with or without progestin, is detrimental to memory in post-menopausal women is complicated by the fact that little is known about the effects of progestins on memory. The present study examined if estrogen, alone or with progesterone, affects spatial memory consolidation in ovariectomized aged female mice. Mice received eight training trials in a spatial Morris water maze followed immediately by injection of water-soluble 17beta-estradiol (E(2); 0.2 mg/kg) or vehicle. Mice were re-tested 24 h later. All mice learned to find the platform on Day 1. On Day 2, the performance of control, but not E(2) mice, deteriorated, suggesting that E(2) enhanced memory for the platform location. In a second experiment, mice were injected with E(2) and 10 or 20 mg/kg water-soluble progesterone. The 10 mg/kg dose of progesterone did not affect estrogen's ability to enhance spatial memory consolidation, but 20 mg/kg blocked this effect. These data indicate that estrogen can improve spatial memory consolidation in aged females and that this effect can be attenuated by progesterone.  相似文献   
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Lymphom am Auge     
Die Ophthalmologie - Die personalisierte Medizin ist mittlerweile Standard in der onkologischen Betreuung von Patienten. Ein Paradebeispiel stellt das Lymphom dar, das durch den intra- und...  相似文献   
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Background

A growing number of women with sporadic unilateral, early-stage breast cancers are undergoing ipsilateral therapeutic mastectomy with contralateral prophylactic mastectomy (CPM) to prevent the development of new cancers in the contralateral breast.

Methods

A decision-tree using TreeAge Pro 2012 software was used to model the costs and effects of CPM versus unilateral mastectomy (UM) in women younger than 50 years of age with sporadic unilateral, early stage breast cancers. Cost estimates were obtained from the Medicare Fee Schedule and the Healthcare Utilization Project. Probability estimates were obtained from the literature. Outcome effects were measured by incremental cost per quality-adjusted life year (QALY) gained. A 10-year risk period for contralateral breast cancer (CBC), a lifetime time horizon, and a societal perspective were used.

Results

Treatment with CPM results in 0.2 QALYs less than UM and $279 less in costs during a 10-year risk period and lifetime follow-up. The resulting incremental cost effectiveness ratio (ICER) is a savings of $1397 per QALY lost. The ICER is sensitive to the rate and method of postmastectomy reconstruction and the cost of radiologic surveillance after UM.

Conclusions

CPM is cost-saving for the prevention of CBC in women younger than 50 years of age with sporadic, unilateral, early-stage breast cancers, but also reduces resulting health. The savings for health lost are insufficient to be considered cost-effective at this time.  相似文献   
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As recent advances have been made in developing tools to fight tuberculosis (TB), there is also a trend towards increasing advocacy by the civil society for TB research and access. One recent successful effort to increase access to treatment options for TB involved a collaborative effort to identify the need for and barriers to the use of rifapentine (RPT) use in the United States. Survey responses confirmed the under-utilization of RPT: 82% of survey respondents selected cost as a significant or potential barrier to use. Survey results provided data to support a year-long advocacy campaign urging the drug company Sanofi to lower the price of RPT. This campaign was based on a common evidence base built in part by the stakeholders themselves. After multiple engagements with communities and providers, Sanofi US announced on 12 December 2013 that they would drop the price of RPT to US$32 per blister pack of 32 tablets for US public health programs. While further work remains to secure access to RPT in the United States and worldwide, the lowering of the price of RPT reflects the positive impact that collaborative advocacy can accomplish, and sets an example for other drug companies to follow.  相似文献   
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