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21.
We report an unusual case of myocardial mycotic aneurysm of the left ventricle resulting from a healed myocardial abscess caused by an aortic regurgitant jet lesion. The diagnosis was made during intraoperative transesophageal echocardiography and confirmed by surgical inspection. The echocardiographic features are described.  相似文献   
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Binocular disparity, the slight differences between the images registered by our two eyes, provides an important cue when estimating the three-dimensional (3D) structure of the complex environment we inhabit. Sensitivity to binocular disparity is evident at multiple levels of the visual hierarchy in the primate brain, from early visual cortex to parietal and temporal areas. However, the relationship between activity in these areas and key perceptual functions that exploit disparity information for 3D shape perception remains an important open question. Here we investigate the link between human cortical activity and the perception of disparity-defined shape, measuring fMRI responses concurrently with psychophysical shape judgments. We parametrically degraded the coherence of shapes by shuffling the spatial position of dots whose disparity defined the 3D structure and investigated the effect of this stimulus manipulation on both cortical activity and shape discrimination. We report significant relationships between shape coherence and fMRI response in both dorsal (V3, hMT+/V5) and ventral (LOC) visual areas that correspond to the observers' discrimination performance. In contrast to previous suggestions of a dichotomy of disparity-related processes in the ventral and dorsal streams, these findings are consistent with proposed interactions between these pathways that may mediate a continuum of processes important in perceiving 3D shape from coarse contour segmentation to fine curvature estimation.  相似文献   
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Currently, no blood biomarker that specifically indicates injury to the proximal tubule of the kidney has been identified. Kidney injury molecule-1 (KIM-1) is highly upregulated in proximal tubular cells following kidney injury. The ectodomain of KIM-1 is shed into the lumen, and serves as a urinary biomarker of kidney injury. We report that shed KIM-1 also serves as a blood biomarker of kidney injury. Sensitive assays to measure plasma and serum KIM-1 in mice, rats, and humans were developed and validated in the current study. Plasma KIM-1 levels increased with increasing periods of ischemia (10, 20, or 30 minutes) in mice, as early as 3 hours after reperfusion; after unilateral ureteral obstruction (day 7) in mice; and after gentamicin treatment (50 or 200 mg/kg for 10 days) in rats. In humans, plasma KIM-1 levels were higher in patients with AKI than in healthy controls or post-cardiac surgery patients without AKI (area under the curve, 0.96). In patients undergoing cardiopulmonary bypass, plasma KIM-1 levels increased within 2 days after surgery only in patients who developed AKI (P<0.01). Blood KIM-1 levels were also elevated in patients with CKD of varous etiologies. In a cohort of patients with type 1 diabetes and proteinuria, serum KIM-1 level at baseline strongly predicted rate of eGFR loss and risk of ESRD during 5–15 years of follow-up, after adjustment for baseline urinary albumin-to-creatinine ratio, eGFR, and Hb1Ac. These results identify KIM-1 as a blood biomarker that specifically reflects acute and chronic kidney injury.  相似文献   
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Exploring non-platinum group metal (n-PGM) based efficient oxygen reduction reaction (ORR) electro-catalysts is highly important for realizing advancement in sustainable next generation-alkaline anion exchange membrane fuel cells (AAEMFCs). Herein, we demonstrate a new “hierarchical shape tuning approach” for the synthesis of controlled sized and shaped non-PGM based Ag ORR electro-catalysts with surface active nano-islands. Hierarchical shapes ranging from spherical (S-AgNs), worm-in-sphere, sphere-in-worm and vermiform (worm-like) Ag nanostructures (V-AgNs) were obtained by precisely varying the ratios of capping agent to dual reducing agents in water at ambient conditions. Compared to S-AgNs, V-AgNs revealed a higher mass normalized ORR Tafel activity (0.303 A mgAg−1 at 0.9 V), onset (1.06 V) and half wave (0.78 V) potentials and higher retention of limiting current density (>88%) after 5000 cycles in 0.5 M potassium hydroxide (KOH) solution attributable to their unique worm like morphology with surface active nano-islands and support free-nature enabled better catalyst utilization. In a fully “non-PGM AAEMFC” (n-PAAEMFC), V-AgNs exhibited the highest fuel cell activity of 115.6 mW cm−2 and stable short-term durability (∼240 h) compared to S-AgNs (41.3 mW cm−2) and previously reported fully n-PAAEMFCs indicating their potential use in next-generation alkaline fuel cells.

A fully non-PGM alkaline membrane fuel cell with “highest fuel cell activity” was achieved using a hierarchically shape-tuned, small, surface-active, support-free, worm-shaped nano-structured silver oxygen reduction reaction electro-catalyst.  相似文献   
29.
Mishandling of antibiotics often leads to the development of multiple drug resistance (MDR) among microbes, resulting in the failure of infection treatments and putting human health at great risk. As a response, unique nanomaterials with superior bioactivity must be developed to combat bacterial infections. Herein, CeO2-based nanomaterials (NMs) were synthesized by employing cerium(iii) nitrate and selective alkaline ions. Moreover, the influence of alkaline ions on CeO2 was investigated, and their characteristics, viz.: biochemical, structural, and optical properties, were altered. The size of nano Ba-doped CeO2 (BCO) was ∼2.3 nm, relatively smaller than other NMs and the antibacterial potential of CeO2, Mg-doped CeO2 (MCO), Ca-doped CeO2 (CCO), Sr-doped CeO2 (SCO), and Ba-doped CeO2 (BCO) NMs against Streptococcus mutans (S. mutans) and Staphylococcus aureus (S. aureus) strains was assessed. BCO outperformed all NMs in terms of antibacterial efficacy. In addition, achieving the enhanced bioactivity of BCO due to reduced particle size facilitated the easy penetration into the bacterial membrane and the presence of a sizeable interfacial surface. In this study, the minimum quantity of BCO required to achieve the complete inhibition of bacteria was determined to be 1000 μg mL−1 and 1500 μg mL−1 for S. mutans and S. aureus, respectively. The cytotoxicity test with L929 fibroblast cells demonstrated that BCO was less toxic to healthy cells. Furthermore, BCO did not show any toxicity and cell morphological changes in the L929 fibroblast cells, which is similar to the control cell morphology. Overall, the results suggest that nano BCO can be used in biomedical applications, which can potentially help improve human health conditions.

The highest antibacterial activity was achieved for Ba-doped CeO2 (BCO) NMs and is suitable for healthcare applications.  相似文献   
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A 10-year-old female child presented with resistant hypertension and hypokalaemia. There was no muscle weakness or periodic paralysis. The ratio of plasma aldosterone concentration to plasma renin activity was increased. MRI of the abdomen showed the right adrenal mass. The child underwent open right adrenalectomy. she had natriuresis in the postoperative period. She was normotensive without antihypertensive drugs at discharge and 2 months after surgery.  相似文献   
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