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61.
Miroljub Todorovic Batric Vukcevic Milenko Cabarkapa Nemanja Vukcevic Tanja Boljevic Nemanja Radojevic 《Forensic science, medicine, and pathology》2018,14(4):503-508
This study aimed to determine the effectiveness of airbags and seatbelts in the prevention of facial fractures and slight facial injuries in relation to the speed and kinetic energy experienced in frontal collisions. All cases of vehicle occupants who had been in frontal collisions and had subsequently been examined in the Institute for Emergency Medical Assistance and the Clinical Center of Montenegro in 2017 were analyzed. There were 29 cases of facial fractures (Group 1), 35 cases of slight facial injuries (including nondisplaced nasal fractures) (Group 2), and 26 cases of occupants who had suffered no facial injuries (control Group 3). In all assessed cases all of the subjects had been wearing a seatbelt and the airbag had deployed at the time of impact. A frontal collision is defined as a collision in which the principal force acts within a range of 90° from the longitudinal axis of the vehicle. Using the mass and the speed of the vehicles, the total kinetic energy (KE) of all frontal collisions being analyzed was calculated. The cut-off value of total KE in frontal collisions that were associated with either facial fractures or slight facial injury was estimated using a receiver operating characteristic (ROC) curve. The cut-off amounts of KE were then used to calculate the barrier equivalent velocity (BEV). The BEV for a vehicle of average mass was estimated to be 55.7 km/h (34.6 mph) in Group 1, and 49.2 km/h (30.6 mph) in Group 2. Airbags and seatbelts are effective in preventing facial injuries in vehicles of average mass that are traveling at speeds under 49.2 km/h (30.6 mph) at the point of impact, but they do not protect from facial fractures when the vehicle speed exceeds 55.7 km/h (34.6 mph). 相似文献
62.
Anti‐inflammatory effects of the GAG‐binding CXCL9(74‐103) peptide in dinitrofluorobenzene‐induced contact hypersensitivity in mice
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63.
Miriam Nannette Ebert Gabriele Beyer-Sehlmeyer Ute Monika Liegibel Tanja Kautenburger Thomas Walter Becker Beatrice Louise Pool-Zobel 《Nutrition and cancer》2013,65(1-2):156-164
Butyrate, one of the major products of gut fermentation, is known to inhibit proliferation, induce apoptosis and differentiation, and increase phase II enzyme activities in tumor cells, whereas little information is available on protective effects in less-transformed colon cells. The aim of this study was to investigate whether the chemoprotective mechanism of glutathione S-transferase (GST) induction by butyrate could also play a role in earlier stages of colon carcinogenesis and whether chemoresistance of cells toward the endogenous genotoxic risk factor 4-hydroxy-2-nonenal (HNE) could be a consequence of butyrate treatment. As cell models, we used the human tumor cell lines HT29 and HT29 clone 19A, a differentiated subclone with properties resembling primary colon cells. We determined the expression of GSTP1 protein (enzyme-linked immunosorbent assay), the major GST in HT29, GSTP1 mRNA (Northern blotting), GST activity, intracellular glutathione, and total protein. The genotoxic impact of HNE (100-200 μM) was compared in butyrate-treated and nontreated cells using single-cell microgel electrophoresis. Our results show that GSTP1 mRNA, GSTP1 protein, GST activity, and total protein were increased (1.2- to 2.5-fold) and glutathione levels were maintained after 24- 72 h of incubation with 4 mM butyrate. Moreover, a marked reduction of HNE-induced genotoxicity was caused by preincubation with butyrate. Butyrate also induced the phosphorylation of extracellular signal-regulated kinases (ERK1/2, Western blotting) after 5-30 min, which indicates a regulation of GST expression by this signal pathway. Most effects were greater in HT29 parent cells than in clone cells. In conclusion, butyrate enhances expression of GST and other proteins in both cell lines, which leads to an enhanced chemoprotection, reducing the impact of HNE genotoxicity. Thus butyrate could play a role in early and later stages of cancer prevention by reducing exposure to relevant risk factors. 相似文献
64.
Shira Meir Drexler Christian J Merz Tanja C Hamacher-Dang Martin Tegenthoff Oliver T Wolf 《Neuropsychopharmacology》2015,40(13):3036-3043
The return of conditioned fear after successful extinction (eg, following exposure therapy) is a significant problem in the treatment of anxiety disorders and posttraumatic stress disorder (PTSD). Targeting the reconsolidation of fear memories may allow a more lasting effect as it intervenes with the original memory trace. Indeed, several pharmacological agents and behavioral interventions have been shown to alter (enhance, impair, or otherwise update) the reconsolidation of reactivated memories of different types. Cortisol is a stress hormone and a potent modulator of learning and memory, yet its effects on fear memory reconsolidation are unclear. To investigate whether cortisol intervenes with the reconsolidation of fear memories in healthy males and how specific this effect might be, we built a 3-day reconsolidation design with skin conductance response (SCR) as a measure of conditioned fear: Fear acquisition on day 1; reactivation/no-reactivation of one conditioned stimulus and pharmacological intervention on day 2; extinction learning followed by reinstatement and reinstatement test on day 3. The groups differed only in the experimental manipulation on day 2: Reactivation+Cortisol Group, Reactivation+Placebo Group, or No-reactivation+Cortisol Group. Our results revealed an enhancing effect of cortisol on reconsolidation of the reactivated memory. The effect was highly specific, strengthening only the memory of the reactivated conditioned stimulus and not the non-reactivated one. Our findings are in line with previous findings showing an enhancing effect of behavioral stress on the reconsolidation of other types of memories. These results have implications for the understanding and treatment of anxiety disorders and PTSD. 相似文献
65.
66.
Delayed childbearing is currently a major challenge in reproductive medicine as increased age has an important impact on successful conception, both in natural and in assisted reproduction. There is a lack of knowledge about the impact of age on fertility, even in highly educated populations. A number of initiatives have been taken to increase fertility awareness. Health care providers have been encouraged to talk with patients about their reproductive life plan (RLP) for almost a decade based on recommendations from the Centres for Disease Control and Prevention. This concept has been explored successfully in Swedish contraception counselling. A growing number of online interventions aim to raise fertility awareness. These websites or interactive tools provide relevant information for individuals and couples as they consider whether they want children, when they should have them, and how many they may wish to have. These interventions are important, because research depicts that knowledge helps people in their decision-making process. With new fertility preservations such as egg freezing now available, additional education is needed to be sure that women and couples are well informed about the cost and low success rates of this intervention. 相似文献
67.
A pedunculated aldosterone‐producing adenoma drained by an extra vein causing puzzling results of adrenal vein sampling
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68.
69.
Carola Eriksson Margareta Larsson Agneta Skoog Svanberg Tanja Tydén 《Upsala journal of medical sciences》2013,118(2):122-129
Background Different reasons influence the current low birth-rate and the postponement of the birth of the first child throughout Europe. The aim of this study was to explore how highly educated women and men in Sweden reflect on fertility and postponed parenthood.Methods We interviewed women (n = 22) and men (n = 18) who had started their professional careers and still had no children. Data were analysed with qualitative content analysis.Results Fertility was perceived as an unconsidered capacity, sometimes unpredictable, and different for women and men, but nevertheless taken for granted. The participants were of the opinion that fertility could be restored by assisted reproductive technologies or replaced by alternatives to a biological child. Postponed parenthood was described as an adaptation to societal changes and current discourses about parenthood as well as a consequence of a contemporary lifestyle with many competing priorities.Conclusion Highly educated young women and men in contemporary Sweden have competing priorities when planning and setting goals for their lives, and having children is one of them. They describe fertility as an imperceptible and retrievable capacity and postponed parenthood as a rational adaptation to changes in society. These findings suggest that increased information about the limitations of human reproduction is needed, but also that societal support for younger parents is of utmost importance. 相似文献
70.
Martin Ruetze Tanja Knauer Stefan Gallinat Horst Wenck Volker Achterberg Annette Maerz Wolfgang Deppert Anja Knott 《Journal of dermatological science》2013,69(2):132-139
BackgroundSkin derived precursors (SKP) comprise a subset of specialized dermal cells that can be distinguished from fibroblast by their capacity for spheroidal growth. Recent investigations have shown that hair follicles constitute a niche for this cell type, but their localization and their definite function in non-follicular skin remains largely unknown.ObjectiveTo identify the dermal niche of non-follicular SKPs and to analyze whether functional aspects correlate with this localization.MethodsSKPs were isolated from separate anatomical regions of human abdominal skin. Fluorescence activated cell sorting then was used to obtain a pure population of non-follicular SKPs. Functional characterization of these cells was performed applying differentiation and proliferation assays. Information on specific in vivo functions was derived from histological evaluation of quantity and localization patterns.ResultsSphere forming capacity and differentiation assays show that SKPs reside in the papillary part of the dermis. Further delineation revealed that the dermal capillaries represent a niche for these cells which subsequently could be isolated by FACS utilizing a perivascular marker. Whereas functional properties described for follicular SKPs could also be detected in the perivascular SKP population, histological analyses additionally point to a cross-talk with epidermal stem cells and a reduction during chronological aging.ConclusionOur data show that SKPs isolated from non-follicular skin originate from a perivascular niche. Compared to their follicular counterparts, no functional differences could be observed upon cultivation, but ex vivo analyses also point to unique functions and a contribution to the phenotype of aged skin. 相似文献