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101.
Involvement of right piriform cortex in olfactory familiarity judgments   总被引:2,自引:0,他引:2  
Previous studies have shown activation of right orbitofrontal cortex during judgments of odor familiarity. In the present study, we sought to extend our knowledge about the neural circuits involved in such a task by exploring the involvement of the right prefrontal areas and limbic/primary olfactory structures. Fourteen right-handed male subjects were tested using fMRI with a single functional run of two olfactory conditions (odor detection and familiarity judgments). Each condition included three epochs. During the familiarity condition, subjects rated whether odors were familiar or unfamiliar. During the detection condition, participants decided if odors were present. When contrasting the familiarity with the detection conditions, activated areas were found mainly in the right piriform cortex (PC) and hippocampus, the left inferior frontal gyrus and amygdala, and bilaterally in the mid-fusiform gyrus. Further analyses demonstrated that the right PC was more strongly activated than the left PC. This result supports the notion that the right PC is preferentially involved in judgments of odor familiarity.  相似文献   
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Furan is toxic and carcinogenic in rodents. Because of the large potential for human exposure, furan is classified as a possible human carcinogen. The detailed mechanism by which furan causes toxicity and cancer is not yet known. Since furan toxicity requires cytochrome P450-catalyzed oxidation of furan, we have characterized the urinary and hepatocyte metabolites of furan to gain insight into the chemical nature of the reactive intermediate. Previous studies in hepatocytes indicated that furan is oxidized to the reactive α,β-unsaturated dialdehyde, cis-2-butene-1,4-dial (BDA), which reacts with glutathione (GSH) to form 2-(S-glutathionyl)succinaldehyde (GSH-BDA). This intermediate forms pyrrole cross-links with cellular amines such as lysine and glutamine. In this article, we demonstrate that GSH-BDA also forms cross-links with ornithine, putrescine, and spermidine when furan is incubated with rat hepatocytes. The relative levels of these metabolites are not completely explained by hepatocellular levels of the amines or by their reactivity with GSH-BDA. Mercapturic acid derivatives of the spermidine cross-links were detected in the urine of furan-treated rats, which indicates that this metabolic pathway occurs in vivo. Their detection in furan-treated hepatocytes and in urine from furan-treated rats indicates that polyamines may play an important role in the toxicity of furan.  相似文献   
104.
Following muscle injury, the damaged tissue and influx of inflammatory cells stimulate the secretion of growth factors and cytokines to initiate repair processes. This release of chemotactic signaling factors activates resident precursor cells and stimulates their mobilization and migration to the site of injury where terminal differentiation can occur. The three transforming growth factor-β (TGF-β) isoforms, and insulin-like growth factor-1 (IGF-1) are among the known regulatory factors released following muscle damage. We investigated the effect of recombinant active TGF-β1, -β2, -β3 and IGF-1 on C2C12 skeletal muscle satellite cell and P19 embryonal carcinoma cell terminal differentiation and migration. C2C12 myoblast fusion as well as P19 embryoid body formation and myogenic differentiation was assessed following 72?h TGF-β treatment (5?ng/ml), whereas the effect of the TGF-β isoforms on migration was determined following 7?h incubation. Our results showed that TGF-β decreases C2C12 myoblast fusion in an isoform-independent manner, whereas in the P19 cell lineage, results demonstrate that TGF-β1 specifically and significantly increased P19 embryoid body formation, but not expression of Connexin-43 or Myosin Heavy Chain. IGF-1 significantly increased migration compared to TGF-β isoforms, which, on their own, had no significant effect on the mobilization of either C2C12 or P19 cells. TGF-β isoforms decreased IGF-1-induced migration of both cell lineages. By distinguishing the factors involved in, and the molecular signals required for, myoblast recruitment during repair processes, strategies can be developed towards improved cell-mediated therapies for muscle injury.  相似文献   
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106.
Computerized ambulatory monitoring overcomes a number of methodological and conceptual challenges to studying mental disorders, however concerns persist regarding the feasibility of this approach with severe psychiatric samples and the potential of intensive monitoring to influence data quality. This multi‐site investigation evaluates these issues in four independent samples. Patients with schizophrenia (n = 56), substance dependence (n = 85), anxiety disorders (n = 45), and a non‐clinical sample (n = 280) were contacted to participate in investigations using computerized ambulatory monitoring. Micro‐computers were used to administer electronic interviews several times per day for a one‐week period. Ninety‐five percent of contacted individuals agreed to participate in the study, and minimum compliance was achieved by 96% of these participants. Seventy‐eight percent of all programmed assessments were completed overall, and only 1% of micro‐computers were not returned to investigators. There was no evidence that missing data or response time increased over the duration of the study, suggesting that fatigue effects were negligible. The majority of variables investigated did not change in frequency as a function of study duration, however some evidence was found that socially sensitive behaviors changed in a manner consistent with reactivity. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
107.
The diagnosis of anaplastic oligodendroglioma (AOD) or anaplastic oligoastrocytoma (AOA) is subject to interobserver variation. The aim of this study was to estimate consensus in typing and grading of these tumors using tumor material collected in a large prospective randomized phase III study and to correlate the consensus diagnosis with the 1p/19q status of the tumors and the clinical outcome. The available pathology material of the first 150 patients, randomized into the European Organization for Research and Treatment of Cancer Trial 26951, was reviewed by an independent panel of 9 neuropathologists. The presence of deletions of 1p and 19q was assessed by fluorescence in situ hybridization with locus-specific probes. The panel reached consensus on the diagnosis of AOD in 52% of the tumors that had been diagnosed as AOD by the local pathologists, whereas only 8% of the local diagnosis of AOA was confirmed with consensus. The concordance on the panel diagnosis of AOD was high (intraclass correlation = 86%). The survival curves for AOD with 1p/19q loss, AOD without these losses, and AOA without 1p/19q loss ran separately in this order. The absence of necrosis and the presence of endothelial abnormalities were correlated with better outcomes. In multivariate analysis, patients' age, 1p/19q loss, and necrosis were identified as independent prognostic factors.  相似文献   
108.
109.
We report a case of an adult who developed superior vena cava syndrome because of cardiac hydatidosis. A 37-year-old man from Morocco developed progressive dyspnoea and cough. Cardiac hydatidosis was diagnosed because of both the typical radiological findings and the positive serology for echinococcosis. The patient was treated by surgery and albendazole without complications.  相似文献   
110.
PURPOSE OF REVIEW: Health-related quality-of-life studies are now recognized as critical to understand the burden of disease and treatments on patients' well being. Significant advances have been recently achieved in gastrointestinal cancers, including the development and clinical use of new robust quality-of-life instruments. We review recent literature to evaluate whether quality-of-life assessment contributes to optimal patient information and helps treatment choices. RECENT FINDINGS: Treatments of gastrointestinal cancers have changed in the last few years with increasing use of multimodal therapies and advances in surgical techniques, especially for low-lying rectal cancers. Concurrent to the development of sphincter-saving procedures, however, the long-term consequences of a permanent stoma on quality of life have been debated. Results of new palliative treatments should also be considered looking at preservation or improvement of quality of life and not only prolongation of life. SUMMARY: Gastrointestinal malignancies impact strongly on patient quality of life due to the aggressiveness of the treatments. Short-term negative effects of surgery and specific deficits in survivors were recently described in gastrointestinal cancers. Baseline quality-of-life data predict length of survival in hepatocarcinoma and metastatic colorectal cancer. Generally, quality-of-life results help to fully inform the patients of the advantages or disadvantages of therapeutic options, including adjuvant and palliative treatments.  相似文献   
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