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971.
Optical coherence tomography angiography(Angio-OCT) has introduced a new non-invasive, quantitative method to assess superficial and deep capillary networks of the retina. In this study, we investigated macular retinal thickness and flow density change following posterior scleral reinforcement(PSR) surgery, using an RTVue XR Avanti Angio-OCT, in patients with pathological myopia. A total of 13 patients with pathological myopia were recruited and all patients completed the 6 months follow-up visit. Data from 22 eyes were used in this study. The mean age was 36.23±15.29 years, and 43%(n=6) were men.Spherical equivalent refractive error(SE) ranged from –8.0 to –24.0 D. Postoperative axial length, best-corrected visual acuity and SE did not change significantly at each follow-up, compared with pre-operative measures(P0.05). Postoperative flow density of superficial and deep retinal layers at each sector did not change significantly at each follow-up, compared with preoperative measures(P0.05). However, we found significant decrease in retinal thickness of parafovea-inferior sector after PSR surgery(P0.01), indicating potential relaxation of vitreofoveal traction after PSR surgery.  相似文献   
972.
Many patients with Alzheimer's dementia (AD) also exhibit noncognitive symptoms such as sensorimotor deficits, which can precede the hallmark cognitive deficits and significantly impact daily activities and an individual's ability to live independently. However, the mechanisms underlying sensorimotor dysfunction in AD and their relationship with cognitive decline remains poorly understood, due in part to a lack of translationally relevant animal models. To address this, we recently developed a novel model of genetic diversity in Alzheimer's disease, the AD‐BXD genetic reference panel. In this study, we investigated sensorimotor deficits in the AD‐BXDs and the relationship to cognitive decline in these mice. We found that age‐ and AD‐related declines in coordination, balance and vestibular function vary significantly across the panel, indicating genetic background strongly influences the expressivity of the familial AD mutations used in the AD‐BXD panel and their impact on motor function. Although young males and females perform comparably regardless of genotype on narrow beam and inclined screen tasks, there were significant sex differences in aging‐ and AD‐related decline, with females exhibiting worse decline than males of the same age and transgene status. Finally, we found that AD motor decline is not correlated with cognitive decline, suggesting that sensorimotor deficits in AD may occur through distinct mechanisms. Overall, our results suggest that AD‐related sensorimotor decline is strongly dependent on background genetics and is independent of dementia and cognitive deficits, suggesting that effective therapeutics for the entire spectrum of AD symptoms will likely require interventions targeting each distinct domain involved in the disease.  相似文献   
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974.
T-cell lymphomas represent a subpopulation of non-Hodgkin lymphomas with poor outcomes when treated with conventional chemotherapy. A variety of novel agents have been introduced as new treatment strategies either as first-line treatment or in conjunction with chemotherapy. Immunotherapy has been demonstrated to be a promising area for new therapeutics, including monoclonal antibodies and adoptive cellular therapeutics. T-cell therapeutics have been shown to have significant success in the treatment of B-cell malignancies and are rapidly expanding as potential treatment options for other cancers including T-cell lymphomas. Although treating T-cell lymphomas with T-cell therapeutics has unique challenges, multiple targets are currently being studied both preclinically and in clinical trials.  相似文献   
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Fire is a key driver in savannah systems and widely used as a land management tool. Intensifying human land uses are leading to rapid changes in the fire regimes, with consequences for ecosystem functioning and composition. We undertake a novel analysis describing spatial patterns in the fire regime of the Serengeti‐Mara ecosystem, document multidecadal temporal changes and investigate the factors underlying these patterns. We used MODIS active fire and burned area products from 2001 to 2014 to identify individual fires; summarizing four characteristics for each detected fire: size, ignition date, time since last fire and radiative power. Using satellite imagery, we estimated the rate of change in the density of livestock bomas as a proxy for livestock density. We used these metrics to model drivers of variation in the four fire characteristics, as well as total number of fires and total area burned. Fires in the Serengeti‐Mara show high spatial variability—with number of fires and ignition date mirroring mean annual precipitation. The short‐term effect of rainfall decreases fire size and intensity but cumulative rainfall over several years leads to increased standing grass biomass and fuel loads, and, therefore, in larger and hotter fires. Our study reveals dramatic changes over time, with a reduction in total number of fires and total area burned, to the point where some areas now experience virtually no fire. We suggest that increasing livestock numbers are driving this decline, presumably by inhibiting fire spread. These temporal patterns are part of a global decline in total area burned, especially in savannahs, and we caution that ecosystem functioning may have been compromised. Land managers and policy formulators need to factor in rapid fire regime modifications to achieve management objectives and maintain the ecological function of savannah ecosystems.  相似文献   
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980.
Ecosystems - Saltmarshes provide many valuable ecosystem services including storage of a large amount of ‘blue carbon’ within their soils. To date, up to 50% of the world’s...  相似文献   
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