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991.
992.

Background  

The purpose of this study is to analyze the diagnostic accuracy of MSCT in the identification of para-aortic lymph node metastases from gastric cancer.  相似文献   
993.
Current membrane oxygenators are constructed for patients with a body surface under 2.2 m(2). If the body surface exceeds 2.5 m(2), commercially available devices may not allow adequate oxygenation during cardiopulmonary bypass. To address this, a hollow-fiber oxygenator with an enlarged contact surface of 1.81 m(2) was tested. In an experimental set-up, six calves of mean weight 85.4 ± 3 kg were connected to cardiopulmonary bypass. They were randomly assigned to a standard oxygenator (n = 3; ADMIRAL, Euroset, Medola, Italy) with a surface of 1.35 m(2) or to an enlarged surface oxygenator (n = 3; AMG, Euroset). Blood samples were taken before bypass, after 10 min on bypass, and after 1, 2, 5 and 6 h of perfusion. Analysis of variance was used for repeated measurements. The mean flow rate was 6.5 l/min for 6 h. The total oxygen transfer at 6 h was significantly higher in the high-surface group (P < 0.05). Blood trauma, evaluated by plasma hemoglobin and lactate dehydrogenase levels, did not detect any significant hemolysis. Thrombocytes and white blood cell count profiles showed no significant differences between the two groups at 6 h of perfusion (P = 0.06 and 0.80, respectively). At the end of testing, no clot deposition was found in the oxygenator, and there was no evidence of peripheral emboli. The results suggest that the new oxygenator allows very good gas transfer and may be used for patients with a large body surface area.  相似文献   
994.
995.
BACKGROUND: Retroareolar cysts present in female adolescents with palpable subareolar masses that can have concomitant inflammatory changes. The purpose of this study was to report our cases of retroareolar cysts and thus to contribute to a better knowledge and understanding of this entity. METHODS: Forty-six girls were diagnosed with retroareolar cysts between December 2000 and July 2002. A retrospective chart review is presented with the clinical and ultrasonographic findings. RESULTS: Age at presentation was 10 to 20 years. The reason for consultation was acute mastalgia and inflammation in 31 cases and palpable nodule in 15 cases. Two patients had areolar discharge.Ultrasonographic imaging in the 46 girls showed retroareolar simple cysts, either multiple or bilateral. The cysts had thin walls and were round, oval, or elongated with a variable diameter always less than 20 mm. They had liquid content with an echogenic or calcific sediment.When retroareolar cysts presented with inflammatory changes, antibiotics and nonsteroidal anti-inflammatory drugs were used. Inflammatory changes disappeared in approximately seven days. All patients experienced favorable outcomes. CONCLUSIONS: Retroareolar cysts are a benign form of breast disease in the adolescent. Further investigation is needed to completely understand the pathophysiology, epidemiology, and natural history of this diagnosis.  相似文献   
996.
Background The significant increase in cardiovascular diseases in developing countries alerts about their impact on underprivileged populations.Objective To identify the relationship of clusters of metabolic syndrome (MS) components with atherosclerosis and chronic inflammation among adults and elderly.Methods Cross-sectional analysis using data from two population-based cohort studies in Florianópolis, Southern Brazil (EpiFloripa Adult Cohort Study, n = 862, 39.9±11.5 years; EpiFloripa Aging Cohort Study, n = 1197, 69.7±7.1 years). Blood pressure (BP), waist circumference (WC), and lipid and glucose levels were analyzed as individual factors or as clusters (either as the number of components present in an individual or as combinations of components). Outcomes included carotid intima-media thickness (IMT), atherosclerotic plaques, and C-reactive protein (CRP) levels. Multiple linear and logistic regression analyses adjusted for confounding factors were used. The statistical significance adopted was 5%.Results Individuals with high BP, elevated WC, dyslipidemia and hyperglycemia (6.1% of the sample) showed higher IMT and CRP than those negatives for all MetS components. Elevated WC was a common determinant of systemic inflammation, while the coexistence of high BP and elevated WC (clusters of two or three factors) was associated with higher IMT (β between +3.2 and +6.1 x 10-2 mm; p value < 0.05) and CRP (EXPβ between 2.18 and 2.77; p value < 0.05).Conclusion The coexistence of high BP and elevated WC was associated with increased IMT and CRP levels, but central obesity affected systemic inflammation either alone or in combination with other risk factors.  相似文献   
997.

Introduction

This contribution presents a magnetic resonance imaging (MRI) acquisition technique named Tissue Border Enhancement (TBE), whose purpose is to produce images with enhanced visualization of borders between two tissues of interest without any post-processing.

Methods

The technique is based on an inversion recovery sequence that employs an appropriate inversion time to produce images where the interface between two tissues of interest is hypo-intense; therefore, tissue borders are clearly represented by dark lines. This effect is achieved by setting imaging parameters such that two neighboring tissues of interest have magnetization with equal magnitude but opposite sign; therefore, the voxels containing a mixture of each tissue (that is, the tissue interface) possess minimal net signal. The technique was implemented on a 7.0 T MRI system.

Results

This approach can assist the definition of tissue borders, such as that between cortical gray matter and white matter; therefore, it could facilitate segmentation procedures, which are often challenging on ultra-high-field systems due to inhomogeneous radiofrequency distribution. TBE allows delineating the contours of structural abnormalities, and its capabilities were demonstrated with patients with focal cortical dysplasia, gray matter heterotopia, and polymicrogyria.

Conclusion

This technique provides a new type of image contrast and has several possible applications in basic neuroscience, neurogenetic research, and clinical practice, as it could improve the detection power of MRI in the characterization of cortical malformations, enhance the contour of small anatomical structures of interest, and facilitate cortical segmentation.  相似文献   
998.
Purpose: An International League Against Epilepsy (ILAE) consensus classification system for focal cortical dysplasias (FCDs) has been published in 2011 specifying clinicopathologic FCD variants. The aim of the present work was to microscopically assess interobserver agreement and intraobserver reproducibility for FCD categories among an international group of neuropathologists with different levels of experience and access to epilepsy surgery tissue. Methods: Surgical FCD specimens covering a broad histopathology spectrum were retrieved from 22 patients with epilepsy. Three surgical nonepilepsy specimens served as controls. A total of 188 slides with routine or immunohistochemical stainings were digitalized with a slide scanner to allow Internet‐based microscopy review. Nine experienced neuropathologists were invited to review these cases twice at a time gap of 3 months and different orders of case presentation. The 2011 ILAE FCD consensus classification served as instruction. Kappa analysis was calculated to estimate interobserver and intraobserver agreement levels. In a third evaluation round, 21 additional neuropathologists with different experience and access to epilepsy surgery reviewed the same case series. Key Findings: Interobserver agreement was good (κ = 0.6360), with 84% consensus of diagnoses during the first evaluation (21 of 25 cases). Kappa values increased to 0.6532 after reevaluation, and consensus was obtained in 24 (96%) of 25 cases. Overall intraobserver reproducibility was also good (κ = 0.7824, ranging from 0.4991 to 1.000). Fewest changes in the classification were made in the FCD type II group (2.2% of 225 original diagnoses), whereas the majority of changes occurred in FCD type III (13.7% of 225 original diagnoses). In the third evaluation round, interobserver agreement was reflected by the level of experience of each neuropathologist, with κ values ranging from moderate (0.5056; high level of experience >40 cases/year) to low (0.3265; low level of experience <10 cases/year). Significance: Our study achieved a good and reliable interobserver agreement among the group of expert neuropathologists originally involved in the ILAE FCD consensus classification system. Intraobserver reproducibility in this group was even more robust. These results showed considerable improvement compared to a previous study evaluating the 2004 Palmini FCD classification. Agreement levels were lower in our second group of neuropathologists and were related to their level of access and experience with epilepsy surgery specimens. These results suggested that the more precise ILAE definition of FCD histopathology patterns improves operational procedures in the diagnosis of FCDs. On the other hand, microscopic assessment of FCD is a challenge and requires sustained experience and teaching. The virtual slide review system allowed testing of this hypothesis and reached a widespread group of participating colleagues from different centers all over the world. We propose to further use this tool as a teaching device and also to address other epilepsy‐associated entities still difficult to classify such as hippocampal sclerosis, long‐term epilepsy‐associated tumors, or mild malformations of cortical development (mMCDs), which were not yet covered by current ILAE classification systems.  相似文献   
999.
Purpose: Previous studies have shown that inhibition of the mammalian target of rapamycin (mTOR) pathway with rapamycin prevents epileptogenesis after pharmacologically induced status epilepticus (SE) in rat models of temporal lobe epilepsy. Because rapamycin is also known for its immunosuppressant properties we hypothesized that one of the mechanisms by which it exerts this effect could be via suppression of brain inflammation, a process that has been suggested to play a major role in the development and progression of epilepsy. Methods: Rats were treated with rapamycin or vehicle once daily for 7 days (6 mg/kg/day, i.p.) starting 4 h after the induction of SE, which was evoked by electrical stimulation of the angular bundle. Hereafter rapamycin was administered every other day until rats were sacrificed, 6 weeks after SE. Video‐electroencephalography was used to monitor the occurrence of seizures. Neuronal death, synaptic reorganization, and microglia and astrocyte activation were assessed by immunohistologic staining. Fluorescein was administered to quantify blood–brain barrier leakage. Key Findings: Rapamycin treatment did not alter SE severity and duration compared to vehicle treatment rats. Rapamycin‐treated rats developed hardly (n = 9) or no (n = 3) seizures during the 6‐week treatment, whereas vehicle‐treated rats showed a progressive increase of seizures starting 1 week after SE (mean 8 ± 2 seizures per day during the sixth week). Cell loss and sprouting that normally occur after SE were prominent but on average significantly less in rapamycin‐treated rats versus vehicle‐treated rats. Nevertheless, various inflammation markers (CD11b/c and CD68) were dramatically upregulated and not significantly different between post‐SE groups. Of interest, blood–brain barrier leakage was barely detected in the rapamycin‐treated group, whereas it was prominent in the vehicle‐treated group. Significance: mTOR inhibition led to strong reduction of seizure development despite the presence of microglia activation, suggesting that effects of rapamycin on seizure development are not due to a control of inflammation. Whether the effects on blood–brain barrier leakage in rapamycin‐treated rats are a consequence of seizure suppressing properties of the drug, or contribute to a real antiepileptogenic effect still needs to be determined.  相似文献   
1000.
Recent advances in medicine, intensive care and diagnostic imaging modalities have led to a pronounced reduction in deaths and disability resulting from traumatic brain injury. However, there are not sufficient findings to evaluate and quantify the severity of the initial and secondary processes destructive and therefore there are not effective therapeutic measures to effectively predict the outcome. For this reason, in recent decades, researchers and clinicians have focused on specific markers of cellular brain injury to improve the diagnosis and the evaluation of outcome. Many proteins synthesized in the astroglia cells or in the neurons, such as neuron-specific enolase, S100 calcium binding protein B, myelin basic protein, creatine kinase brain isoenzyme, glial fibrillary acidic protein, plasma desoxyribonucleic acid, brain-derived neurotrophic factor, and ubiquitin carboxy-terminal hydrolase-L1, have been proposed as potential markers for cell damage in central nervous system. Usually, the levels of these proteins increase following brain injury and are found in increasing concentrations in the cerebrospinal fluid depending on the injury magnitude, and can also be found in blood stream because of a compromised blood-brain barrier. In this review, we examine the various factors that must be taken into account in the search for a reliable non-invasive biomarkers in traumatic brain injury and their role in the diagnosis and outcome evaluation.  相似文献   
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