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71.
Acute esophageal necrosis (AEN) or “black esophagus” is a rare condition presented by patients with critical state of health and characterized by a darkened esophagus, usually the distal third, in upper digestive endoscopy. The main clinical manifestation is upper gastrointestinal bleeding and there may be abdominal pain, dysphagia, nausea, vomiting, fever and syncope associated. The diagnosis depends on clinical suspicion and performing endoscopy, the biopsy not being required. In this article we present a case of a patient who had lots of comorbidities and developed AEN during a post-operative period, and discuss the importance of AEN in an increasingly ageing population.  相似文献   
72.
Aberrant activation of the hypoxia inducible factor (HIF) pathway causing overexpression of angiogenic genes, like vascular endothelial growth factor (VEGF), is one of the underlying causes of ocular neovascularization (NV) and metastatic cancer. Consistently, along with surgical interventions, a number of anti-VEGF agents have been approved by FDA for the treatment of ocular neovascular diseases. These anti-VEGF agents, like ranibizumab/lucentis, have revolutionized the treatment in the past decade. However, substantial vision improvement is observed only in a subset of age-related macular degeneration patients receiving ranibizumab. Further, all current therapies are associated with limitations and side effects. For example, surgeries cause tissue destruction and inflammation while anti-VEGF therapies are expensive, require repeated administration, and offer temporary relief from vascular leakage. These factors impose significant cost and treatment burdens to both the patient and society. With an aging population in most western countries with a continually increasing number of patients on lifelong treatment for these retinal diseases, the focus of ocular drug development for neovascular diseases will be to improve efficacy while reducing treatment costs. Blocking the HIF pathway, a major regulator of ocular NV and cancer, offers an appealing therapeutic strategy. Therefore, this review summarizes HIF inhibitors that have been recently evaluated for the treatment of different cancers and ischemic retinopathies.  相似文献   
73.
Investments in community-based HIV prevention programs in Ontario over the past two and a half decades are assumed to have had an impact on the HIV epidemic, but they have never been systematically evaluated. To help close this knowledge gap, we conducted a macro-level evaluation of investment in Ontario HIV prevention programs from the payer perspective. Our results showed that, from 1987 to 2011, province-wide community-based programs helped to avert a total of 16,672 HIV infections, saving Ontario’s health care system approximately $6.5 billion Canadian dollars (range 4.8–7.5B). We also showed that these community-based HIV programs were cost-saving: from 2005 to 2011, every dollar invested in these programs saved about $5. This study is an important first step in understanding the impact of investing in community-based HIV prevention programs in Ontario and recognizing the impact that these programs have had in reducing HIV infections and health care costs.  相似文献   
74.
The predictive value of vascular biomarkers such as pulse wave velocity (PWV), central arterial pressure (CAP), and augmentation index (AIx), obtained through pulse wave analysis (PWA) in resting conditions, has been documented in a variety of patient groups and populations. This allowed to make appropriate recommendations in clinical practice guidelines of several scientific societies. Due to advances in technologies, largely operator-independent methods are currently available for estimating vascular biomarkers also in ambulatory conditions, over the 24 h. According to the acceptable accuracy and reproducibility of 24-h ambulatory PWA, it appears to be a promising tool for evaluating vascular biomarkers in daily life conditions. This approach may provide an opportunity to further improve the early cardiovascular screening in subjects at risk. However, concerning the clinical use of PWA over the 24 h in ambulatory conditions at the moment, there is no sufficient evidence to support its routine clinical use. In particular, long-term outcome studies are needed to show the predictive value of 24-h PWV, CAP, and AIx values, provided by these devices, over and beyond peripheral blood pressure, and to answer the many technical and clinical questions still open. To this regard, the VASOTENS Registry, an international observational prospective study recently started, will help providing answers on a large sample of hypertensive patients recruited worldwide.  相似文献   
75.
It is important to recognize factors that might predict poor outcome and prognosis in patients with AAV. The predictors reported in the literature encompass genetic, histopathological, and clinical ones. Genetic studies (genetic predictors) have found genes that are associated with prediction of poor response to treatment, deterioration of renal function, and risk of mortality. Histopathological studies (histopathological predictors) have shown that sclerotic renal lesions are associated with increased risk of progression to end-stage renal disease and death. Lastly, scores (clinical predictors) obtained with tool as FFS, Maldini risk score, VDI, and emerging new biomarkers could potentially be helpful in assessment of prognosis in the future.  相似文献   
76.
77.
Avulsion injuries of the knee are common sequelae of significant trauma given the number of ligamentous and tendinous insertions around the joint. Commonly discussed avulsion fractures of the lateral knee include the Segond fracture of the lateral tibial plateau and the arcuate complex avulsion fracture of the fibular styloid process. A less common avulsion fracture is the iliotibial (IT) band avulsion fracture involving the anterolateral corner of the tibia (Gerdy’s tubercle). It is crucial to identify IT band avulsion fractures because of the frequent associated internal derangements of the knee. This case report describes the imaging of an acute IT band avulsion fracture and compares these findings with other lateral knee avulsion fractures.  相似文献   
78.
Cardiovascular disease (CVD) remains the leading cause of death in the developed countries and is estimated to be the leading cause of death in the developing countries by the year 2030. The cause for this rise in CVD is the increase in the major CVD risk factors (CVRFs) like hypertension, obesity, diabetes, and hyperlipidemia, which account for 80 % of all CVD deaths worldwide. In order to prevent the increase in CVD, it has been proposed to develop a low-cost polypill containing four to five generic drugs with known effectiveness in the reduction of the CVRFs. This polypill has now been tested in several recent studies for the primary and secondary prevention of CVD and stroke with fairly good results. A Medline search of the English language literature between 2011 and 2015 resulted in the identification of 15 studies with pertinent findings. These findings together with collateral literature will be discussed in this review.  相似文献   
79.
To effectively track targets under partial occlusion and illumination variation, an improved target tracking method based on combination of sparse representation and particle filtering is proposed in this paper. We regard the candidate target particle set as redundant dictionary and the target template as observation signal to reduce the computational complexity and enhance the real-time performance of target tracking. Besides, to enhance tracking robustness for better adaption to illumination and occlusion, the density histogram, local binary pattern feature fusion, trivial templates and energy control parameters are also utilized in this study. Finally, extensive simulation experiments under different circumstances show that the proposed method performs better compared with other methods, and the average computation time decreases greatly.  相似文献   
80.
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