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81.
82.
Comijs HC Beekman AT Smit F Bremmer M van Tilburg T Deeg DJ 《Journal of affective disorders》2007,103(1-3):243-246
BACKGROUND: The study investigates whether persons who have experienced childhood adversity are more likely to develop depressive symptoms when faced with recent events. METHOD: Data were used from a population-based sample, aged 55 to 85 years (n=1887), which were not depressed at baseline. Childhood adversities and recent stressful life events were retrospectively assessed. Depressive symptoms were measured with the CES-D. RESULTS: 14.4% of our sample experienced adverse events during childhood (<18 yrs) and 35.4% experienced recent events. Associations of depressive symptoms were found with both, childhood adversity (OR 1.80, 95% CI 1.21-2.69) and recent life events (OR 1.42, 95% CI 1.01-2.00). The effect of recent events on depressive symptoms was not modified by childhood adversity. LIMITATIONS: Underreporting may be present due to unwillingness to report embarrassing events or to disclose painful memories. CONCLUSIONS: No evidence was found for the assumption that older persons were more vulnerable for depression in reaction to recent life events when they were exposed to childhood adversity. 相似文献
83.
Swennen GR Mommaerts MY Abeloos J De Clercq C Lamoral P Neyt N Casselman J Schutyser F 《The Journal of craniofacial surgery》2007,18(3):533-539
A detailed visualization of the interocclusal relationship is essential in a three-dimensional virtual planning setup for orthognathic and facial orthomorphic surgery. The purpose of this study was to introduce and evaluate the use of a wax bite wafer in combination with a double computed tomography (CT) scan procedure to augment the three-dimensional virtual model of the skull with a detailed dental surface. A total of 10 orthognathic patients were scanned after a standardized multislice CT scanning protocol with dose reduction with their wax bite wafer in place. Afterward, the impressions of the upper and lower arches and the wax bite wafer were scanned for each patient separately using a high-resolution standardized multislice CT scanning protocol. Accurate fitting of the virtual impressions on the wax bite wafer was done with surface matching using iterative closest points. Consecutively, automatic rigid point-based registration of the wax bite wafer on the patient scan was performed to implement the digital virtual dental arches into the patient's skull model (Maxilim, version 2.0; Medicim NV, St-Niklaas, Belgium). Probability error histograms showed errors of < or =0.16 mm (25% percentile), < or =0.31 mm (50% percentile), and < or =0.92 (90% percentile) for iterative closest point surface matching. The mean registration error for automatic point-based registration was 0.17 +/- 0.07 mm (range, 0.12-0.22 mm). The combination of the wax bite wafer with the double CT scan procedure allowed for the setup of an accurate three-dimensional virtual augmented model of the skull with detailed dental surface. However, from a clinical workload, data handling, and computational point of view, this method is too time-consuming to be introduced in the clinical routine. 相似文献
84.
85.
Georg F. Weber Filip K. Swirski 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2014,399(1):1-9
Background
Sepsis is an unsolved problem worldwide, with a 30–50 % mortality rate. The recent failures of anti-TLR4, recombinant activated protein C, and anti-TNF in clinical trials indicate a need to rethink our current understanding of sepsis’s pathophysiology. While the initial immune response is crucial for effective clearance of invading pathogens, an overly exuberant host response to infection can cause septic shock, tissue damage, and death. Profuse inflammation in sepsis is frequently followed by global immunosuppression that increases susceptibility to viral and bacterial infections. Despite the dangers of immune over-response, the immune system’s anti-inflammatory activities are likely necessary to reduce the initial over-activation of the immune system.Purpose
With this review, we want to illuminate the different aspects of immune response to sepsis and provide insight to the ongoing difficulties currently present within sepsis research.Conclusion
Future treatment strategies for sepsis should focus on maintaining balance between pro- and anti-inflammatory immune actions in a timely manner. 相似文献86.
Short‐term splenic impact of single‐strand DNA functionalized multi‐walled carbon nanotubes intraperitoneally injected in rats
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Simona Clichici Alexandru Radu Biris Cornel Catoi Adriana Filip Flaviu Tabaran 《Journal of applied toxicology : JAT》2014,34(4):332-344
In recent years, a great deal of studies have focused on the possible toxicity of carbon nanotubes (CNT), as a result of their potential applications in the field of nanotechnologies. The investigation of spleen toxicity is part of the carbon nanotubes‐induced toxicity assessment. In this study, we investigated the possible toxic effects of CNT on the rat spleen, after intraperitoneally (i.p.) administration of a single dose [1.5 ml; 2 mg multi‐walled (MW) CNT per body weight (bw)] of multi‐walled carbon nanotubes (exterior diameter 15–25 nm, interior diameter 10–15 nm, surface 88 m2 g–1) functionalized 1:1 with single‐strand DNA (ss‐DNA‐MWCNT, 270 mg l–1). CNT functionalization with DNA determines a stable dispersion in the body fluids. For the detection of carbon nanotubes in the spleen, Raman spectroscopy, histopathologic examination, confocal microscopy and transmission electron microscopy (TEM) were performed at different time points (1, 6, 24, 48 and 144 h) after MWCNT administration. The dynamics of oxidative stress parameters (malondialdehyde, protein carbonyls and reduced glutathione), along with nitrosative stress parameters (nitric oxide, inducible NO synthase), the pro‐inflammatory cytokines [interleukin‐(IL)‐1β] and the number of cells expressing caspase 3 and proliferating cell nuclear antigen (PCNA) were assessed. Our results indicate that, after i.p. administration, MWCNT translocate progressively in the spleen, with a peak of concentration after 48 h, and determine lymphoid hyperplasia and an increase in the number of cells which undergo apoptosis, in parallel with the enhancement of the mitosis in the white pulp and with transient alterations of oxidative stress and inflammation that need further investigations for a longer period of monitoring. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
87.
Multi jet fusion (MJF) technology has proven its significance in recent years as this technology has continually increased its market share. Recently, polypropylene (PP) was introduced by Hewlett-Packard for the given technology. To our knowledge, little is known about the mechanical properties of polypropylene processed by MJF technology. During this study, standardised specimens were printed under all of the major orientations of the machine’s build space. Each of these orientations were represented by five samples. The specimens then underwent tensile, bending and Charpy impact tests to analyse their mechanical properties. The structural analysis was conducted to determine whether PP powder may be reused within the MJF process. The mechanical tests showed that the orientation of the samples significantly influences their mechanical response and must be carefully chosen to obtain the optimal mechanical properties of PP samples. We further showed that PP powder may be reused as the MJF process does not significantly alter its thermal and structural properties. 相似文献
88.
Due to the increasing popularity of tattoos among the general population, to ensure their safety and quality, there is a need to develop reliable and rapid methods for the analysis of the composition of tattoo inks, both in the ink itself and in already existing tattoos. This paper presents the possibility of using Raman spectroscopy to examine tattoo inks in biological materials. We have developed optical tissue phantoms mimicking the optical scattering coefficient typical for human dermis as a substitute for an in vivo study. The material employed herein allows for mimicking the tattoo-making procedure. We investigated the effect of the scattering coefficient of the matrix in which the ink is located, as well as its chemical compositions on the spectra. Raman surface line scanning has been carried out for each ink in the skin phantom to establish the spatial gradient of ink concentration distribution. This ensures the ability to detect miniature concentrations for a tattoo margin assessment. An analysis and comparison of the spectra of the inks and the tattooed inks in the phantoms are presented. We recommend the utilization of Raman spectroscopy as a screening method to enforce the tattoo ink safety legislations as well as an early medical diagnostic screening tool. 相似文献
89.
90.
Filip Cierniak Felicitas von Arnim Gerald Heckel Rainer G. Ulrich Martin H. Groschup Martin Eiden 《Viruses》2021,13(6)
Hepatitis E is an emerging viral disease that is the leading cause of viral hepatitis in the world. The vast majority of hepatitis E cases in developed countries are caused by zoonotic genotypes 3 and 4 of hepatitis E virus (HEV) for which pig and wild boar and to lesser extent rabbits are the main reservoir. According to recent reports rabbits are a source of human HEV infection and highlight the risk of zoonotic foodborne transmission. Here we report the molecular analysis of a novel HEV strain identified in a rabbit during a countrywide surveillance of rabbits and hares in Germany, 2016. The analysis of the complete genome reveals characteristics of a putative novel recombinant subtype of the species Orthohepevirus A within the clade of genotype 3 but not closely related to any known subtypes. Importantly, the genome of this strain possesses a nucleotide exchange in the overlapping region of open reading frames ORF2/ORF3 interfering with a broadly applied diagnostic real-time RT-PCR. In conclusion, a new type of HEV strain was identified in a German rabbit with atypical and novel sequence characteristics. 相似文献