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Critically ill patients are frequently at risk of neurological dysfunction as a result of primary neurological conditions or secondary insults. Determining which aspects of brain function are affected and how best to manage the neurological dysfunction can often be difficult and is complicated by the limited information that can be gained from clinical examination in such patients and the effects of therapies, notably sedation, on neurological function. Methods to measure and monitor brain function have evolved considerably in recent years and now play an important role in the evaluation and management of patients with brain injury. Importantly, no single technique is ideal for all patients and different variables will need to be monitored in different patients; in many patients, a combination of monitoring techniques will be needed. Although clinical studies support the physiologic feasibility and biologic plausibility of management based on information from various monitors, data supporting this concept from randomized trials are still required.  相似文献   
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ObjectiveTo analyse the methylation status of the Long Interspersed Nuclear Element-1 (LINE-1) and Short Interspersed Nuclear Element Alu (Alu) of peripheral blood mononuclear cells (PBMCs) from patients with migraine compared with healthy control subjects.MethodsThis case–control study recruited patients with migraine without aura and age-matched healthy control subjects. PBMCs were purified from peripheral blood samples. Methylation levels and patterns of LINE-1 and Alu sequences were evaluated using combined bisulfite restriction analysis-interspersed repetitive sequences polymerase chain reaction.ResultsA total of 84 patients with migraine and 82 age-matched healthy controls were enrolled in the study. High levels of unmethylated cytosines in both the LINE-1 and Alu repetitive elements were observed in the migraine group compared with the control subjects. In addition, a significant difference was detected in the methylation level of LINE-1 between TT and CC genotype groups of the methylenetetrahydrofolate reductase gene.ConclusionsThese results suggest that analysis of epigenetic biomarkers in PBMCs may help to identify patients at a higher risk of migraine development.  相似文献   
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The induction of heme oxygenase-1 (HO-1) was studied in intact spinal cords and injured spinal cords after a moderate, thoracic contusion injury. HO-1 was immunolocalized in the normal cord and along the axis of the cord at 1, 2, 3 and 4 days after contusion. Induction of this enzyme in astrocytes and microglia/macrophages was evaluated using immunofluorescent double labeling with monoclonal antibodies to HO-1 and either glial fibrillary acidic protein or the complement C3bi receptor. HO-1 was expressed in neurons in the normal spinal cord. After contusion, HO-1 was induced in both gray and white matter at the impact site. In segments of cord that were 1 cm proximal or distal to the injury, HO-1 was primarily induced in the dorsal columns and occasionally in the lateral white matter. This pattern of induction was noted at all time points. The HO-1 was induced primarily in microglia/macrophages. The distribution of the HO-1 positive cells closely correlated with the pattern of intraparenchymal hemorrhage. These findings demonstrate acute induction of HO-1 in non-neuronal cells in the injured spinal cord. Induction of HO-1 in glia may be a consequence of multiple factors including exposure to heme proteins, hypoxia and oxidative stress.  相似文献   
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Serological Activity of Lipids of a T strain of Mycoplasma   总被引:1,自引:1,他引:0       下载免费PDF全文
Complement-fixing activity of a T strain of Mycoplasma was found to be associated with its lipid components. Heat stability and lability of periodate and beta-glucosidase treatments led to the conclusion that complement-fixing, active lipids had carboydrate determinants. Periodate treatment of chromatographic fractions of a chloroform-methanol extract showed that only antigens contained in the acetone fraction were periodate labile. Lipids also appeared to be involved in the passive hemagglutination, since the lipid fraction active in complement fixation also combined and blocked the action of antibodies which agglutinated sensitized erythrocytes with strain P108.  相似文献   
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A 24-year-old man was admitted at the emergency department with a lower quadrant abdominal pain and a slight hypoglycaemia. Abdominal ultrasonography showed the presence of a fluid peritoneal collection and a 3.2 x 2.5 cm hypoisoechogenic mass closed to the left iliac vessels with an echo-color-Doppler pattern similar to that of a hamartoma. CT examination confirmed the hypothesis of a vascular tumour. Although an abdominal angiography added no new information to establish a preoperative diagnosis, it showed a well vascularized mass. The patient underwent laparoscopy that revealed a bleeding mass of the great omentum. Laparoscopic stapled resection of the greater omentum was carried out. The solid lesion consisted of spindle-shaped cells, but no atypical cells were observed. The histological findings were diagnostic of a benign solitary fibrous tumor, an extremely rare neoplasm for a long time considered to be an exclusively thoracic lesion. This is the first case of a solitary fibrous tumor presenting as haemoperitoneum and the first time it was removed laparoscopically. The patient is disease-free at the 2-year follow-up.  相似文献   
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