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21.
BACKGROUND: The risk of hemorrhagic complications after extracorporeal shock-wave lithotripsy (ESWL) increases in patients with aspirin intake, but the hematoma-inducing mechanism has not been understood completely at the ultrastructural level. METHODS: The effect off shock-waves on the kidneys of male Wistar-rats (n=24) was investigated in an experimental setting using a special ESWL device. Ultrastructural examination was performed by light-, transmission electron- and scanning electron microscopy. RESULTS: Shock-wave induced tissue damage appeared in all kidneys independently of aspirin intake. Endothelial detachment, lethal cell injury, gaps and mechanical disruption of the glomerular basement membrane were regularly found. After 1 week, repair processes were completed with evidence of permanent fibrosis in some cases. CONCLUSIONS: ESWL can induce modest as well as fatal damage to renal tissue cells. Therefore, after an ESWL-induced hematoma a second ESWL should not be performed within 1 week of the first treatment. 相似文献
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Punkae Mahaisavariya MD Angkana Chaiprasert DR.reR.naT. Apichati Sivayathorn MD Supakan Khemngern MABS 《International journal of dermatology》1999,38(4):279-284
BACKGROUND: Deep fungal and higher bacterial skin infections occur fairly frequently in Thailand. METHODS: Cases with a provisional diagnosis of deep fungal and higher bacterial infections were prospectively collected from 1994 to 1997 in the Granuloma Clinic, Department of Dermatology, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand. Demographic data, clinical manifestations, causative organisms, histologic features, treatment, and outcome were investigated. RESULTS: The total cases in a 4-year period numbered 27. The male to female ratio was approximately 1:1. Mycetoma was most common, followed by chromoblastomycosis. Actinomycetoma was similar in incidence to eumycetoma. The only causative organism that could be identified among the mycetoma cases was Cladosporium carrionii, which caused mycetoma of the buttock of an aplastic anemia patient at the site of bone marrow aspiration. Surgical treatment was recommended for eumycetoma. Chromoblastomycosis was caused by C. carrionii and F. compactum and responded well with itraconazole orally. Mycotic abscesses were found in four cases, basidiobolomycosis in two cases, and cutaneous nocardiosis in one case. Cotrimoxazole was recommended in the treatment of actinomycetoma, cutaneous nocardiosis, and basidiobolomycosis. CONCLUSIONS: Localized, chronic, slow, progressive, and usually asymptomatic were the main cutaneous manifestations of deep fungal and higher bacterial skin infections. A skin biopsy for histologic study and culture identification should be performed in every suspected case. The causative organisms were found in the histologic sections of every case, but only about one-third were found by culture. 相似文献
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Older adults show age-related reductions in memory for neutral items within complex visual scenes, but just like young adults, older adults exhibit a memory advantage for emotional items within scenes compared with the background scene information. The present study examined young and older adults' encoding-stage effective connectivity for selective memory of emotional items versus memory for both the emotional item and its background. In a functional magnetic resonance imaging (fMRI) study, participants viewed scenes containing either positive or negative items within neutral backgrounds. Outside the scanner, participants completed a memory test for items and backgrounds. Irrespective of scene content being emotionally positive or negative, older adults had stronger positive connections among frontal regions and from frontal regions to medial temporal lobe structures than did young adults, especially when items and backgrounds were subsequently remembered. These results suggest there are differences between young and older adults' connectivity accompanying the encoding of emotional scenes. Older adults may require more frontal connectivity to encode all elements of a scene rather than just encoding the emotional item. 相似文献
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Alessandro Addis Elena Canciani Marino Campagnol Matteo Colombo Christian Frigerio Daniele Recupero Claudia Dellavia Marco Morroni 《Materials》2022,15(3)
Different xenogeneic inorganic bone substitutes are currently used as bone grafting materials in oral and maxillo-facial surgery. The aim of the present study was to determine the physicochemical properties and the in vivo performance of an anorganic equine bone (AEB) substitute. AEB is manufactured by applying a process involving heating at >300 °C with the aim of removing all the antigens and the organic components. AEB was structurally characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray fluorescence (XRF), and Fourier-transformed infrared (FT-IR) spectroscopy and compared to the anorganic bovine bone (ABB). In order to provide a preliminary evaluation of the in vivo performance of AEB, 18 bone defects were prepared and grafted with AEB (nine sites), or ABB (nine sites) used as a control, in nine Yucatan Minipigs. De novo bone formation, residual bone substitute, as well as local inflammatory and tissue effects were histologically evaluated at 30 and 90 days after implantation. The structural characterization showed that the surface morphology, particle size, chemical composition, and crystalline structure of AEB were similar to cancellous human bone. The histological examination of AEB showed a comparable pattern of newly formed bone and residual biomaterial to that of ABB. Overall, the structural data and pre-clinical evidence reported in the present study suggests that AEB can be effectively used as bone grafting material in oral surgery procedures. 相似文献
26.
Julia G Halilova Donna Rose Addis R Shayna Rosenbaum 《Social cognitive and affective neuroscience》2020,15(8):815
Does the tendency to adjust appraisals of ourselves in the past and future in order to maintain a favourable view of ourselves in the present require episodic memory? A developmental amnesic person with impaired episodic memory (HC) was compared with two groups of age-matched controls on tasks assessing the Big Five personality traits and social competence in relation to the past, present and future. Consistent with previous research, controls believed that their personality had changed more in the past 5 years than it will change in the next 5 years (i.e. the end-of-history illusion), and rated their present and future selves as more socially competent than their past selves (i.e. social improvement illusion), although this was moderated by self-esteem. Despite her lifelong episodic memory impairment, HC also showed these biases of temporal self-appraisal. Together, these findings do not support the theory that the temporal extension of the self-concept requires the ability to recollect richly detailed memories of the self in the past and future. 相似文献
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Histopathology of the pleura 总被引:1,自引:0,他引:1
This review attempts to provide up to date information on structure/function relationships of the pleura and on the pathology of pleural effusions, pneumothorax, pleural repair, pleural infections, pleural involvement in systemic connective tissue disorders, non-malignant asbestos-induced pleural disease, mesothelioma and other pleural tumours. 相似文献
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