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1.
We study the image formation of vibro-acoustography systems based on a concave sector array transducer taking into account depth-of-field effects. The system point-spread function (PSF) is defined in terms of the acoustic emission of a point-target in response to the dynamic radiation stress of ultrasound. The PSF on the focal plane and the axis of the transducer are presented. To extend the obtained PSF to the 3D-space, we assume it is a separable function in the axial direction and the focal plane of the transducer. In this model, an image is formed through the 3D convolution of the PSF with an object function. Experimental vibro-acoustography images of a breast phantom with lesion-like inclusions were compared with simulated images. Results show that the experimental images are in good agreement with the proposed model.  相似文献   
2.
Metformin (Met) has been shown to have pleiotropic effects such as neuroprotective, antioxidant, and anti‐inflammatory properties making that a potential candidate for the treatment of central nervous system (CNS) disorders. This study was designed to investigate the possible effect of Met on the d ‐galactose (d ‐gal)‐induced aging in ovariectomized mice. The female mice underwent bilateral ovariectomy. d ‐gal was administered orally at a dose of 500 mg/kg, and Met was administrated orally at doses of 1 and 10 mg/kg for 6 weeks. Anxiety‐like behavior was evaluated by the elevated plus‐maze. Physical power was assessed by vertical grid holding test and forced swimming capacity test. The brains were assessed for the level of superoxide dismutase (SOD) and brain‐derived neurotrophic factor (BDNF). Ovariectomy caused anxiety and declined the physical power as well as BDNF and SOD levels. d ‐gal administration in ovariectomized mice exacerbated these deleterious effects. Met hampered the anxiety‐like behavior and strengthened the physical power of d ‐gal‐treated ovariectomized mice. Met also increased the SOD and BDNF levels in the brains of d ‐gal‐treated ovariectomized animals. Based on the obtained results, we suggest Met administration as a novel therapeutic approach for the treatment of age‐related conditions in the absence of female sex hormones.  相似文献   
3.
Ultrasound bladder vibrometry (UBV) parameters have been shown in previous studies to strongly correlate with measurements from urodynamic studies. Just like urodynamic studies, UBV can be performed in supine and sitting positions. The objective of this study is to compare UBV parameters obtained in the two different positions using statistical methods. We recruited eight volunteers with healthy bladders for this purpose. The elasticity, group velocity squared and thickness of the bladder were the UBV parameters of interest, and their values were recorded at different bladder volumes for each volunteer. The results presented indicate that the measurements made in the two positions are in agreement using the Bland–Altman method and a parameter q which compares the values at each bladder volume for each volunteer. UBV parameters were also repeatable for measurements recorded in the supine and sitting positions.  相似文献   
4.
Introduction and objectiveBeneficial effects of glucosamine in spatial learning and memory impairment induced by scopolamine has been evaluated in rats by using Morris water maze.MethodsMale Wistar rats were randomly divided into control, scopolamine and scopolamine plus glucosamine groups. All injections were given in 5 consecutive days and 30 min after each injection, the rats were tested in the Morris water maze test. Escape latency and path length to reach the hidden platform were subjected to analysis of variance [ANOVA].ResultsThe rats treated with scopolamine showed increased escape latency and path length to reach the hidden platform compared to control group (P < 0.001). Both escape latency and traveled path length to reach the hidden platform in glucosamine treated animals (1 and 2 g/kg) were significantly lower (P < 0.05 to P < 0.001) than in the scopolamine group.ConclusionThe results of this study showed that the glucosamine can inhibit scopolamine-induced impairments of spatial learning and memory in rats. Glucosamine might offer a promise in either the prevention or the treatment of neurodegenerative diseases such as Alzheimer's disease.  相似文献   
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Objective Giant pituitary adenomas (≥40 mm) pose a major management challenge. We describe the experience of a single surgeon and a dedicated neuro‐endocrine team with multimodality treatment of these tumours in three specialized institutions. Design Retrospective data set analyses. Patients Fifty‐one consecutive patients with a giant adenoma (39 endocrine‐inactive, 12 endocrine‐active; mean tumour diameter 45 mm) treated over 10 years by an endonasal transsphenoidal approach were included. All patients had surgical resection followed by radiotherapy and/or medical therapy as judged necessary. Measurements Hormonal and visual status, extent of resection, tumour control rates, complications and use of medical and radiotherapy were evaluated. Results Surgery resulted in gross total, near total and subtotal removal in21 (41%), 10 (20%) and 20 (39%) patients respectively. Complete tumour removal was associated with absence of cavernous sinus invasion (P < 0·001). Long‐term endocrine function improved in 49% of patients and new endocrinopathy occurred in 14·6%; 76% required long‐term hormone replacement therapy. Vision improved in 81·5% of the patients and there was no visual worsening. At the last follow up (median 30 months), tumour control was achieved in 96% of patients: 59% with surgery alone, 20% with surgery plus focussed radiotherapy, 18% with surgery and medical therapy and two with all three modalities. Conclusions Endonasal surgery provides effective initial treatment for patients with giant adenomas. Multimodality therapy was needed in almost 50% of patients and this rate will likely increase with longer follow up. Close collaboration of neurosurgeons with endocrinologists and radiation oncologists is essential for optimal treatment of patients with these challenging tumours.  相似文献   
8.
Drug misuse is increasing and diversifying in Iran. This study is the first to explore in detail the impact on, and ways of coping used by, spouses of addicted men in Iran. Semi-structured interviews were conducted with 24 spouses. Four main themes were identified in the data: heart-breaking news of the husband’s addiction; coping alone; progressive deterioration and suffering; and disruption of family relationships and finances. Reactions upon learning of the husband’s addiction involved shock and collapse, and/or fear, disbelief and confusion. Spouses tried to hide the problem and to solve the problem alone, feeling for a long time as if they were “walking in the dark” without any social support and exposed to stigma. As time had gone on they had experienced distress and turmoil, and mixed feelings towards, and loss of trust and confidence in, their husbands, whose behaviour was increasingly unreliable. This had led to impairment in the relationship, and financial stress, and a general degradation and disruption of normal family life, leading to strain for spouses, akin to a state of burnout. Present findings confirm the conclusions of similar research conducted in other countries, that substance misuse in the family can have devastating effects for spouses, on children and all aspects of family life. The situation for Iranian wives may be compounded by the relatively closed nature of family life, and the existence of culturally based attitudes, including shame, towards “family defects” such as addiction. More information and support is needed for Iranian families of addicted individuals.  相似文献   
9.
Abstract

Background: Enteroendocrine cells (EEC) have been suggested to have a role in the pathogenesis of irritable bowel syndrome (IBS). Although many studies have analysed possible numeric changes of EEC in IBS, the results differ between different studies. One reason might be due to difficulties in standardising the morphometric method.

Aim: The aim of this study was to compare two different methods for counting EEC in jejunum biopsies from patients with IBS and healthy controls.

Method: Fifty-one patients with IBS and 35 healthy controls were included in the study. Jejunum mucosa was procured using a Watson capsule. Slides were immunostained for serotonin and chromogranin A and then scanned digitally. The morphometry was done by counting cells per high power field (hpf) and per mm2 after defining area of the mucosa. The two methods were compared using Bland Altman analysis.

Results: There was no difference in the number of EEC in patients with IBS compared to healthy controls. The number of cells detected by per mm2 area of mucosa were higher than number of cells per hpf. Counting EEC per high power field systematically underestimated the number of cells in the mucosal area.

Conclusions: Counting cells per mm2 mucosal area gives a better representation of the number of EEC in small bowel mucosa. The finding of no difference in EEC numbers does not imply an equal function and further studies are needed to evaluate the role, if any of EEC, in IBS.  相似文献   
10.
Journal of Thrombosis and Thrombolysis - Ventilation/perfusion (V/Q) imaging and computed tomography pulmonary angiography (CTPA) are common tools for acute pulmonary embolism (PE) diagnosis....  相似文献   
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