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1.
Shape and letter cancellation test performance was investigated among large samples of African American, Hispanic, and White non-demented elders. Ethnic minority elders took significantly longer to complete both tasks compared to Whites. An index of task efficiency, which simultaneously measures time and accuracy, suggested that slower time by minority elders was not related to a measurable effort to achieve greater accuracy. The frequency of commission errors was greater in our sample than in previous reports, especially among ethnic minority elders. Although significant differences were observed between the ethnic groups when matched for years of education, equating for literacy level eliminated all performance differences between African Americans and Whites on both cancellation tasks.  相似文献   
2.
We hypothesized that the pathological effects on the neonatal rat heart could be aggravated by Cu deficiency due to the combined effects of caffeine exposure and malnutrition. Upon birth, pups were mixed and randomly picked; 8 pups were assigned to each dam and then divided into 4 groups. Group 1 dams received a normal diet containing 20% protein. Group 2 dams were fed 20% protein diet supplemented with caffeine (4 mg/100 g BW). Group 3 dams received 6% protein diet as a malnourished group, and group 4 dams received 6% protein diet supplemented with caffeine (4 mg/100 g BW). On postnatal day 10, dams and pups were killed. Group 2 tended to have a decrease in the Cu levels of dams' plasma and milk and in pups' plasma and heart tissue compared to those of group 1. This pattern was not observed consistently between groups 3 and 4. Transmission electron microscopy of group 2 pups' hearts revealed a degree of disruption in the mitochondria compared to normal mitochondria seen in group 1. There was no consistent change in the mitochondria of group 4 compared to group 3. The caffeine level observed in all categories of group 4 (dams' plasma and milk, pups' plasma and heart tissue) was lower than those in group 2. Although malnutrition affected body weight and heart weight, combined effects of caffeine and malnutrition on Cu content in the neonatal heart was relatively minor compared to the well nourished group. This well nourished group showed that the effects of caffeine on Cu were more consistent, resulting the changes of mitochondria.  相似文献   
3.
Vascular structures of skin are important biomarkers in diagnosis and assessment of cutaneous conditions. Presence and distribution of lesional vessels are associated with specific abnormalities. Therefore, detection and localization of cutaneous vessels provide critical information towards diagnosis and stage status of diseases. However, cutaneous vessels are highly variable in shape, size, color and architecture, which complicate the detection task. Considering the large variability of these structures, conventional vessel detection techniques lack the generalizability to detect different vessel types and require separate algorithms to be designed for each type. Furthermore, such techniques are highly dependent on precise hand-crafted features which are time-consuming and computationally inefficient. As a solution, we propose a data-driven feature learning framework based on stacked sparse auto-encoders (SSAE) for comprehensive detection of cutaneous vessels. Each training image is divided into small patches of either containing or non-containing vasculature. A multilayer SSAE is designed to learn hidden features of the data in hierarchical layers in an unsupervised manner. The high-level learned features are subsequently fed into a classifier which categorizes each patch into absence or presence of vasculature and localizes vessels within the lesion. Over a test set of 3095 patches derived from 200 images, the proposed framework demonstrated superior performance of 95.4% detection accuracy over a variety of vessel patterns; outperforming other techniques by achieving the highest positive predictive value of 94.7%. The proposed Computer-Aided Diagnosis (CAD) framework can serve as a decision support system assisting dermatologists for more accurate diagnosis, especially in teledermatology applications in remote areas.  相似文献   
4.
Atrial fibrillation is the most common arrhythmia in adults and its prevalence is growing rapidly. It has been shown that AF is associated with increased risk of heart failure, ischemic and hemorrhagic stroke, and mortality. Hence, there is growing interest among researchers in seeking preventive and therapeutic interventions regarding AF. In recent decades, it has been suggested that statins may decrease the incidence of AF and may also decrease its recurrence after cardioversion and catheter ablation. These effects are thought to be mediated by different mechanisms such as modulating inflammation, altering the properties of transmembrane ion channels, interfering with activation of matrix metalloproteinases, and acting on endothelial function. In this article, we review and update current knowledge about the role of statins in primary and secondary prevention of AF in general and specific populations.  相似文献   
5.
Previous investigations demonstrated that immune responses play critical roles in the defense against visceral leishmaniasis (VL). A key regulator of immune responses is the cytokine, IL-10 and polymorphisms within its promoter which could alter its expression. Thus, the aim of this study was to examine the correlation between polymorphism at the ?819 position of the IL-10 gene and VL in a selected Iranian population. This cross-sectional study was performed on 100 patients with clinical presentation of VL and seropositive for the leishmania (group 1), 62 patients without clinical presentation but seropositive (group 2), and 128 healthy controls (group 3). The IL-10 ?819 polymorphism was evaluated using the PCR-RFLP technique. The anti-leishmania antibody titration was assessed using an immunofluorescence assay. Our results showed that the polymorphism at IL-10 ?819 (C/T) position was significantly associated with VL, and C/T genotype was significantly higher in VL patients when compared to groups 2 and 3 (p?<?0.001). However, the results demonstrated that the C and T alleles were not associated with VL (p?=?0.855). The data presented here confirm the results of previous reports that polymorphisms at the ?819 position of the IL-10 gene can influence susceptibility to VL suggesting that the C/T genotype may be considered as a risk factor for the disease.  相似文献   
6.
Background: Mass violence, atrocities, and political upheavals have affected the prosperity and psychological health of the people of Iraq. Those living in the Garmian region of the Kurdistan Region of Iraq are among those most affected. While there is an urgent need for mental health interventions in this region, mental health resources are scarce, and only a small percentage of the population in need receive mental health care. Despite the high burden of mental illness, and the general demand by the community and local authorities for social and psychological services, effective validated cost-effective interventions tailored to address the cultural and social problems are scarce. This retrospective case series study, which is based on the lead author's experiences in the Garmian region, aims to describe the results of using two mental health interventions, cognitive behavioral therapy and thought field therapy.Methods and findings: The files of 31 clients that met criteria of the study were selected using purposive sampling. The results showed that, of the 13 clients who received Cognitive Behavioral Therapy, one improved and others showed either no change in symptoms, deterioration of symptoms, or dropped out of treatment. All 11 clients who received only Thought Field Therapy, showed improvement in their symptoms. Seven clients who received Cognitive Behavioral Therapy and showed no improvement received Thought Field Therapy, and showed improvement finally. While the results of preliminary experience with Thought Field Therapy in the Garmian community is encouraging, conducting randomized controlled trials with follow-ups, and comparing Thought Field Therapy with other therapeutic approaches is needed to substantiate these findings.Conclusion: We found that Thought Field Therapy had positive results in reducing anxiety disorders and trauma related symptoms, as compared to Cognitive Behavioral Therapy.  相似文献   
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8.
Direct C–H bond oxidation of organic materials, and producing the necessary oxygenated compounds under mild conditions, has attracted increasing interest. The selective oxidation of various alkylbenzenes was carried out by means of a new catalyst containing VO2+ species supported on silica-coated Fe3O4 nanoparticles using t-butyl hydroperoxide as an oxidant at room temperature in H2O or solvent-free media. The chemical and structural characterization of the catalyst using several methods such as FTIR spectroscopy, XRD, FETEM, FESEM, SAED, EDX and XPS showed that VO2+ is covalently bonded to the silica surface. High selectivity and excellent conversion of various toluene derivatives, with less reactive aliphatic (sp3) C–H bonds, to related benzoic acids were quite noticeable. The aerobic oxygenation reaction of these alkylbenzenes was studied under the same conditions. All the results accompanied by sustainability of the inexpensive and simple magnetically separable heterogeneous catalyst proved the important criteria for commercial applications.

A highly efficient, recoverable, sustainable, economic and eco-friendly catalyst containing VO2+ species supported on SiO2@Fe3O4 nanoparticles for selective oxidation of alkylbenzenes using TBHP or O2 at room temperature in H2O or solvent-free media.  相似文献   
9.
ObjectiveIncreasingly, medical journals are recognizing “equally credited authors” (ECA) in the primary and senior authorship of articles. The aim of this study was to assess the policies of co–first authorship, co–senior authorship, and designation of a corresponding author in the radiology literature.MethodsWe identified 29 radiology journals based on impact factor ranking. Journal offices were contacted by phone and e-mail to ascertain their practices on first and senior authorship ECA designations. We surveyed the March, June, and December 2018 issues of each journal (when available) to assess the utilization of the co-designations in articles.ResultsTwenty-five of 29 journals responded to our survey (response rate: 86.2%). Of 25 journals, 20 (80%) allowed co–first authorship. Among these, 4 of 25 journals (16%) allowed more than two co–first authors. Among the 25 responses, 14 journals (56%) allowed co–senior authorship. Among the 24 journals who responded to this specific question, 23 (96%) approved designation of a corresponding author, different from the first or senior author. The review of March, June, December 2018 editions found co–first authorship and co–senior authorship ECA rates of 8.6% (range 0.0%-22.7%) and 1.8% (range 0.0%-13.3%), respectively. A corresponding author other than first or senior author was noted in 13.3% (range 0.0%-34.7%).DiscussionThere has been widespread acceptance of the concept of ECA in the policies of the top cited imaging journals particularly for first authors (80%). However, the utilization of these designations is uncommon for first authorship (8.6%) and rare (1.8%) for senior authorship based on our 2018 sampling.  相似文献   
10.
BACKGROUNDThere is recently a concern regarding the reinfection and reactivation of previously reCoVered coronavirus disease 2019 (CoVID-19) patients.AIMTo summarize the recent findings and reports of CoVID-19 reinfection in patients previously reCoVered from the disease.METHODSThis study was a systematic review of current evidence conducted in August 2020. The authors studied the probable reinfection risk of novel coronavirus (CoVID-19). We performed a systematic search using the keywords in online databases. The investigation adheres to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist to ensure the reliability and validity of this study and results.RESULTSWe reviewed 31 studies. Eight studies described reCoVered patients with reinfection. Only one study reported reinfected patients who died. In 26 studies, there was no information about the status of the patients. Several studies indicated that reinfection is not probable and that post-infection immunity is at least temporary and short.CONCLUSIONBased on our review, we concluded that a positive polymerase chain reaction retest could be due to several reasons and should not always be considered as reinfection or reactivation of the disease. Most relevant studies in positive retest patients have shown relative and probably temporary immunity after the reCoVery of the disease.  相似文献   
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