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Diffuse axonal injury (DAI) is seen as widespread damage in the white matter of brain characterized by morphological changes to axons throughout the brain and brain stem. The current study attempted to investigate the effect of increasing impact energy on the presence and severity of DAI in corpus callosum (CC). DAI was induced in adult male Sprague-Dawley rats using an injury model adapted from Marmarou et al. in 1994. A 450-g cylindrical brass weight was dropped from three different heights (2.0 m, 1.5 m and 1.0 m) on to a metal helmet affixed to the skull of the rats. In the sham group, rats underwent a surgical procedure with no impact. After a 24-h survival period the animals were transcardially perfused. The brain was removed and the cerebral hemispheres were sectioned with a vibrotome and stained by silver impregnation technique. The CC of all the impacted rats showed DAI in the form of beaded axons, retraction balls and vacuole-like enlargements. The axonal injury was most severe in the 2-m group, while mildest in the 1-m group. In the sham group, axons appeared to be normal. This study demonstrates evidence of graded DAI depending on the impact energy. Such data is useful for mathematical modeling of axonal injury in rat brain using the same impact parameters and potential determination of injury thresholds for neural trauma. Electronic Publication  相似文献   
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Among children with separated parents, shared residence – i.e., joint physical custody where the child is sharing his or her time equally between two custodial parents’ homes – is increasing in many Western countries and is particularly common in Sweden. The overall level of living among children in Sweden is high; however, the potential structural differences between children in various post-separation family arrangements have not been sufficiently studied. Potential risks for children with shared residence relate to the daily hassles and stress when having two homes. This study aims at investigating the living conditions of children with shared residence compared with children living with two custodial parents in the same household and those living with one custodial parent, respectively. Swedish national survey data collected from children aged 10–18 years (n ≈ 5000) and their parents were used. The outcomes were grouped into: Economic and material conditions, Social relations with parents and peers, Health and health behaviors, Working conditions and safety in school and in the neighborhood, and Culture and leisure time activities. Results from a series of linear probability models showed that most outcomes were similar for children with shared residence and those living with two custodial parents in the same household, while several outcomes were worse for children living with one parent. However, few differences due to living arrangements were found regarding school conditions. This study highlights the inequalities in the living conditions of Swedish children, with those living with one parent having fewer resources compared with other children.  相似文献   
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Aims: The aim of this study is to investigate the effect of mitral stenosis (MS) on left atrial (LA) function using two‐dimensional speckle tracking echocardiography (2DSTE). Methods and Results: The study subjects consisted of 52 patients with asymptomatic MS and 52 control subjects. LA function was assessed using prototype speckle tracking software and manual tracking method. Maximal LA volume (LAVmax) and minimal LA volume (LAVmin) and LA volume before atrial contraction (LAVpre‐a) were measured. Using these volumes, LA reservoir, conduit and booster pump fuction parameters were calculated. Indexed LAVmax, LAVmin, and LAVpre‐a measurements via speckle tracking were highly correlated with manual tracing methods in both groups. Expansion index (67.8 ± 36.4 vs. 148.3 ± 44.2), diastolic emptying index (37.7 ± 12.9 vs. 58.0 ± 8.5), passive emptying (37.3 ± 14.1 vs. 70.4 ± 10.4) and passive emptying index (13.3 ± 6.3 vs. 41.3 ± 10.6) were decreased significantly in MS patients (P < 0.001). In contrast active emptying index (62.6 ± 4.1 vs. 29.5 ± 10.1) increased in MS group (P < 0.001) while active emptying (28.1 ± 13.0 vs. 28.3 ± 6.9) remained same among both groups. Conclusions: This is the first study relating LA volumes and function assessed by 2DSTE to MS. 2D speckle tracking analysis of LA volume is relatively easy and provides more detailed information regarding the changes in LA volumes during the cardiac cycle.  相似文献   
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Churg–Strauss syndrome (CSS) is a rare type of necrotizing vasculitis affecting small to medium-sized vessels typically characterized by asthma, lung infiltrates, necrotizing granulomas and hypereosinophilia. Herein, we describe a case of CSS presenting severe and aggressive course. A 35-year-old male patient with weight loss, dyspepsia, dyspnea and hemoptysis was admitted. The laboratory analyses indicated a remarkable eosinophilia, elevated levels of serum total IgE and positive cANCA. Thorax CT findings were suggestive of alveolar hemorrhage. Bronchoalveolar lavage revealed alveolar hemorrhage with eosinophilia and transbronchial lung biopsy showed eosinophilic vasculitis. Cardiac enzymes were increased and murmurs were audible revealing cardiomyopathy proven by echocardiography. Pulse cyclophosphamide and methyl prednisolone was immediately started. On the 21st day, intestinal perforation developed and urgent surgery was performed. During a follow-up, although a radiological improvement was observed in the chest X-ray, cardiac failure, peripheral neuropathy and skin lesions developed and high-dose intravenous immunoglobulin and anti-TNF therapy (adalimumab) were applied. Despite the therapy, he died from heart failure and septicemia at 68th day of therapy.  相似文献   
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