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71.
Previously we have investigated a depth-independent compensation for collimator detector response (CDR) included in the OSEM reconstruction, intended for SPECT images that have been corrected for scatter and septal penetration using convolution-based methods. In this work, the aim was to study how different filtering strategies affect contrast as a function of noise when using Gaussian smoothing filters in combination with the above-described CDR compensation. The evaluation was performed for (123)I dopamine transporter (DAT) SPECT images. Prefiltering with 2D Gaussian filter kernels, where the deterioration in resolution is included in the depth-independent CDR compensation, was compared to conventional postfiltering with 3D Gaussian filter kernels. Images reconstructed without filtering are also included in the comparison. It was found that there is little benefit in noise reduction when using CDR compensation. However, this variant of prefiltering gives consistently higher contrasts as a function of noise compared with the postfiltering alternative, and that could be of interest when using other types of filters with contrast improving properties. 相似文献
72.
Wilfried Smidt Gisela Kammermeyer Susanna Roux Christiane Theisen Christian Weber 《Early child development and care》2018,188(10):1340-1353
The career success of preschool teachers has been discussed to be important because it can be a precondition for the ability to provide a high-quality preschool education. Consequently, the identification of factors that can help explain individual differences in career success is a crucial research issue. Previous research covering various occupations indicates that the Big Five, internal locus of control (LOC), and occupational self-efficacy are good predictors of objective and subjective career success. However, there is a research gap on this topic in preschool teachers. This study examined whether the Big Five, LOC, and occupational self-efficacy could predict the career success of 560 preschool teachers in Germany. After controlling for other predictors, internal LOC corresponded with higher objective career success, but neuroticism and conscientiousness corresponded with lower subjective career success. Occupational self-efficacy corresponded with higher subjective career success. The findings are discussed with respect to practical conclusions. 相似文献
73.
Papacchini F Dall'Oca S Chieffi N Goracci C Sadek FT Suh BI Tay FR Ferrari M 《The journal of adhesive dentistry》2007,9(1):25-31
PURPOSE: To compare the 24-h microtensile bond strength of a microfilled hybrid composite to the same material after mechanical and/or chemical treatment and assess the effect of oxygen inhibition on the composite-composite bond. MATERIALS AND METHODS: Forty composite cylinders of Gradia Direct Anterior (GC) were prepared and stored 24 h prior to the following surface treatments: 50-microm aluminum oxide air abrasion and 37% phosphoric acid etching (group 1); hydrochloric acid and 6.9% hydrofluoric acid etching (group 2); diamond bur roughening and 37% phosphoric acid etching (group 3); diamond bur roughening (group 4). In all groups, Prime & Bond NT (Dentsply De Trey) was applied and light cured in air or under a nitrogen atmosphere, prior to layering a buildup of the repairing resin composite. Microtensile bond strength measurements were performed. Data were statistically analyzed with two-way ANOVA and Tukey's test (alpha = 0.05). RESULTS: The curing atmosphere did not significantly influence the interfacial strength (p < 0.05). Surface treatment significantly affected the composite-composite bond (p > 0.05). Air abrasion, regardless of curing atmosphere, resulted in the strongest bond (p < 0.05). The other treatments were comparable. CONCLUSION: Air abrasion and the application of a bonding agent offer satisfactory bond strengths for composite repair. The oxygen inhibition layer on a light-cured adhesive is not crucial to the success of the 24-h composite-composite bond. 相似文献
74.
Woo PC Lau SK Lin AW Curreem SO Fung AM Yuen KY 《Diagnostic microbiology and infectious disease》2007,58(2):251-254
We report the first case of surgical site abscess caused by Lactobacillus fermentum from a 53-year-old woman with squamous cell carcinoma of the esophagus after transthoracic esophagectomy and neoadjuvant chemoirradiation. 16S rRNA gene sequencing is a useful tool to better characterize the epidemiology and clinical significance of L. fermentum. 相似文献
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Bacigaluppi Susanna Bragazzi Nicola Luigi Martini Mariano 《Neurosurgical review》2020,43(6):1443-1449
Neurosurgical Review - Fedor Krause’s inspiring biography shows the value of translational thinking: one of the fathers of modern neurosurgery, this gifted child was recognized for his... 相似文献
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Monica Locatelli Simona Buelli Anna Pezzotta Daniela Corna Luca Perico Susanna Tomasoni Daniela Rottoli Paola Rizzo Debora Conti Joshua M. Thurman Giuseppe Remuzzi Carlamaria Zoja Marina Morigi 《Journal of the American Society of Nephrology : JASN》2014,25(8):1786-1798
Shiga toxin (Stx)–producing Escherichia coli is the offending agent of postdiarrhea-associated hemolytic uremic syndrome (HUS), a disorder of glomerular ischemic damage and widespread microvascular thrombosis. We previously documented that Stx induces glomerular complement activation, generating C3a responsible for microvascular thrombosis in experimental HUS. Here, we show that the presence of C3 deposits on podocytes is associated with podocyte damage and loss in HUS mice generated by the coinjection of Stx2 and LPS. Because podocyte adhesion to the glomerular basement membrane is mediated by integrins, the relevance of integrin-linked kinase (ILK) signals in podocyte dysfunction was evaluated. Podocyte expression of ILK increased after the injection of Stx2/LPS and preceded the upregulation of Snail and downregulation of nephrin and α-actinin-4. Factor B deficiency or pretreatment with an inhibitory antibody to factor B protected mice against Stx2/LPS-induced podocyte dysregulation. Similarly, pretreatment with a C3a receptor antagonist limited podocyte loss and changes in ILK, Snail, and α-actinin-4 expression. In cultured podocytes, treatment with C3a reduced α-actinin-4 expression and promoted ILK-dependent nuclear expression of Snail and cell motility. These results suggest that Stx-induced activation of the alternative pathway of complement and generation of C3a promotes ILK signaling, leading to podocyte dysfunction and loss in Stx-HUS. 相似文献
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Susanna Kallakorpi Kaisa Haatainen Pivi Kankkunen 《International journal of mental health nursing》2019,28(1):117-127
This study aimed to describe the psychiatric nursing care experiences of immigrant patients. The incidence of mental health problems is higher and the use of mental health services is lower among immigrants, especially refugees, compared with the majority of the population. The study uses a qualitative research approach, with an emphasis on focused ethnography research methods. The participants were immigrant patients (N = 14) residing in adult psychiatric wards of certain hospitals (N = 3) selected for the study. A majority of the participants were refugees or asylum seekers. A total of 21 in‐depth interviews were conducted. The experiences of these immigrant patients, both in their home countries and in their country of residence, had had an adverse effect on their mental health, with past traumatic experiences being the most central factor. Their symptoms included depression, anxiety, somatization, and psychosis. The findings show that the categories of factors that helped promote recovery among immigrant patients were nursing, medical treatment, care environment, and the patients' own methods. Based on the findings, a systematic evaluation of traumatic experiences is recommended for immigrants from countries with a history of war and/or political violence. Healthcare providers should also consider the importance of cultural desire in psychiatric nursing for the recovery of patients. 相似文献