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71.
Susanna Graham Vasanti Jadva Tabitha Freeman Kamal Ahuja Susan Golombok 《Human fertility (Cambridge, England)》2016,19(4):230-241
The objective of this study was to examine the motivations, experiences and future expectations of identity-release egg donors in the UK following the removal of donor anonymity and the increase in financial compensation for egg donation. This exploratory, in-depth qualitative study comprised semi-structured interviews with 11 women who had attended an egg donation screening appointment at a UK clinic during a four-month period in 2014. Interviews were conducted two to six weeks after the woman had donated or had withdrawn/been rejected from the donation process. Participants’ primary motivation for donating was to help infertile women have their ‘own child’, and the recent increase in financial compensation did not seem to play a significant role in their decision. All were happy to be identifiable and contacted by children born as a result of their donation. However, some were hesitant about providing non-identifying information about themselves for these offspring and wished for further information about the recipient(s) of their eggs and the outcome of their donation. Whilst this study was limited due to the small sample size, it is the first study of UK egg donors following the rise in donor compensation and suggests that other strategies may be more effective in increasing donor numbers. 相似文献
72.
Impaired expression of perforin and granulysin in CD8+ T cells at the site of infection in human chronic pulmonary tuberculosis 下载免费PDF全文
Protective immunity in tuberculosis is dependent on the coordinated release of cytolytic effector molecules from effector T cells and the subsequent granule-associated killing of infected target cells. In this study, we investigated the expression of cytolytic (perforin and granzyme A) and antimicrobial (granulysin) molecules at the single-cell level in cryopreserved lung tissue from patients with chronic, progressive tuberculosis disease. Quantification of protein-expressing cells was performed by in situ imaging, while mRNA levels in the infected tissue were analyzed by real-time PCR. Persistent inflammation, including excessive expression of inducible nitric oxide synthase in CD68+ macrophages and significant infiltration of CD3+, CD8+ and CD4+ T cells, was evident in tuberculosis lesions in all patients. However, despite the accumulation of CD3+ T cells, perforin- and granulysin-expressing CD3+ T cells were detected at two- to threefold-lower ratios in the tuberculosis lesions than in distal lung parenchyma and uninfected control lungs, respectively. This was evident at both the protein and mRNA levels. Moreover, perforin- and granulysin-expressing CD8+ T cells were scarce in individual granulomas within the tuberculosis lesions. In contrast, significant up-regulation of granzyme A-expressing CD3+ T cells was evident in the lesions from all patients. Confocal microscopy revealed coexpression of perforin and granulysin, primarily in CD8+ T cells; however, this expression was lower in the tuberculosis lesions. These findings suggest that symptomatic, chronic tuberculosis disease is associated with insufficient up-regulation of perforin and granulysin coexpression in CD8+ T cells at the local site of infection. 相似文献
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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
75.
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
76.
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
77.
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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79.
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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