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There has been much debate recently over the functional role played by the planum temporale (PT) within the context of the dorsal auditory processing stream. Some studies indicate that regions in the PT support spatial hearing and other auditory functions, whereas others demonstrate sensory-motor response properties. This multifunctionality has led to the claim that the PT is performing a common computational pattern matching operation, then routing the signals (spatial, object, sensory-motor) into an appropriate processing stream. An alternative possibility is that the PT is functionally subdivided with separate regions supporting various functions. We assess this possibility using a within subject fMRI block design. DTI data were also collected to examine connectivity. There were four auditory conditions: stationary noise, moving noise, listening to pseudowords, and shadowing pseudowords (covert repetition). Contrasting the shadow and listen conditions should activate regions specific to sensory-motor processes, while contrasting the stationary and moving noise conditions should activate regions involved in spatial hearing. Subjects (N = 16) showed greater activation for shadowing in left posterior PT, area Spt, when the shadow and listen conditions were contrasted. The motion vs. stationary noise contrast revealed greater activation in a more medial and anterior portion of left PT. Seeds from these two contrasts were then used to guide the DTI analysis in an examination of connectivity via streamline tractography, which revealed different patterns of connectivity. Findings support a heterogeneous model of the PT, with functionally distinct regions for sensory-motor integration and processes involved in auditory spatial perception.  相似文献   
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Background Albumin is a protein colloidal solution with limited availability and high cost. It should be used in such approved indications as paracentesis, extensive burn, spontaneous bacterial peritonitis, and nephrotic syndrome. Objectives The aim of this study was to evaluate and compare the appropriateness of albumin usage before and after an evidence-based guideline. Setting Four wards of Imam Reza Hospital, Mashhad, Iran. Method An interventional pre–post design study was performed on 2 groups of patients; in gGroup 1 as a preparation phase group in 6 months from February 2015 to July 2015 and Group 2 as an interventional group from September 2015 to February 2016. A guideline for proper indications of albumin, designed and finalized based on the physicians’ comments, was implemented in Group 2. Main outcome measure The pattern of albumin consumption. Results Fifty patients were evaluated in each group. The implementation of the guideline resulted in reduction of improper albumin use from 62 to 57.5%, which was not statistically significant; however., it reduced inappropriate dose and duration of albumin therapy (55.5–16.7%), the number of consumed albumin vial, and the average cost for each patient (317.78 ± 3.15–149.81 ± 1.91 USD) significantly, as well. Conclusion This study illustrated that in this hospital in most cases, albumin was used inappropriately and at an alarming rate. This improved after the introduction of an evidence-based guideline. Moreover, guideline implementation resulted in significant cost reduction.  相似文献   
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AIM To investigate the relationship between 25-hydroxyvitamin D [25(OH)D] levels and fibrosis stage in patients with non-alcoholic fatty liver disease(NAFLD).METHODS Two individual reviewers identified relevant studies using the Pub Med, EMBASE, Cochrane, and Scopus databases. Inclusion criteria were as follows:(1) Studies that evaluated adults with NAFLD and serum or plasma 25(OH)D levels; and(2) assessed fibrosis stage using liver biopsy. A rigorous analysis yielded six articles as having sufficient data to employ in evaluating the association of serum vitamin D levels in patients with NAFLD based on their liver fibrosis stage by histopathological analysis. The lead investigators of each of the six studies were contacted and the data were collected. To meta-analyze vitamin D levels in F0-F2 vs F3-F4 fibrosis, a random-effects meta-analysis fit using restricted maximum likelihood was applied. To examine trends across each stage of fibrosis with respect to vitamin D levels, a meta-regression was performed. P 0.05 was considered statistically significant. RESULTS A total of 937 subjects from six studies were included in the final analysis to evaluate the association of serum vitamin D levels in patients with NAFLD based on their liver fibrosis stage by histopathological analysis. The lead investigators of each of the six studies were contacted and the data were collected. First, the investigators performed a meta-analysis to compare serum vitamin D levels in patients with NAFLD with stage F0-F2 compared to F3-F4, which did not show significance [meta-estimate of the pooled mean difference =-0.86, P = 0.08(-4.17, 2.46)]. A metaregression evaluation of serum vitamin 25(OH)D levels across the individual stages(F0-F4) of fibrosis did not show an association for the six included studies.CONCLUSION Low vitamin D status is not associated with higher stages of liver fibrosis in patients with NAFLD.  相似文献   
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Objectives:The effect of metallic objects on the fractal dimension (FD), bone area fraction (BAF) and gray scale values (GSVs) of cone-beam CT (CBCT) images was assessed. Also, FD, BAF and GSV were compared among CBCT, digital periapical and panoramic radiographies.Methods:Digital periapical and panoramic radiographs were acquired from six blocks of bovine rib. Additionally, different arrangements of titanium implants and intracanal metallic posts were created in the bone blocks and CBCT scans were taken from the different implant-root arrangements. The three radiographical modalities were compared by analysis of variance. Pairwise comparisons between the modalities were performed by the Tukey test (significance level set at 0.05).Results:Different root-implant arrangements in the CBCT images revealed no significant differences in the FD (p = 0.920), BAF and GSV values (p = 0.623). FD differed significantly among the three modalities (p < 0.001). Significant differences were found between CBCT and each of the periapical and panoramic techniques (p < 0.001), while no remarkable differences were observed in the FD of the periapical and panoramic images (p = 0.294). BAF and GSV showed significantly different results among the three radiographical techniques (p < 0.001). The difference was remarkable between CBCT and periapical (p < 0.001), CBCT and panoramic (p < 0.001) and periapical and panoramic (p = 0.008).Conclusion:Presence of titanium implants and intracanal posts does not produce different results in the fractal analysis (FA) of the CBCT images. The trabecular bone pattern is best assessed by FA of the periapical radiographs followed by the panoramic and CBCT techniques, respectively.  相似文献   
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BACKGROUND: The primary objective of this study was to measure the prevalence, incidence, and resolution of insulin resistance (IR) in critically ill patients. A secondary objective was to explore the relationship between IR and inflammatory cytokines, coagulation abnormalities, and clinical outcomes. Design: Prospective observational study. METHODS: The setting was the medical/surgical intensive care unit (ICU). We enrolled consecutive patients within 24 hours of admission to the ICU. Blood samples were collected daily until discharge, death, or a maximum of 10 days, then sent for measurement of markers of IR, inflammation, and coagulation. Charts were reviewed retrospectively to determine clinical outcomes. The homeostasis model assessment method (HOMA) was used to determine IR; a score of > or = 4 represents insulin resistance. RESULTS: A total of 96 patients were enrolled. Upon admission, 64 (67%) patients had overt IR (glucose > 7 mmol/L or insulin use), 9 (9.4%) had non-overt IR (normal glucose but HOMA > 4), and 23 (24%) were insulin sensitive (IS; normal glucose and HOMA < 4). During the course of ICU stay, an additional 16 patients developed overt IR, while 10 (10%) remained IS. There were no significant differences in inflammatory markers, coagulation tests, and clinical outcomes between IR and IS patients. There was no significant correlation between HOMA and inflammatory markers and coagulation markers. In a multivariable regression model, only interleukin-6 levels were significantly associated with mortality. CONCLUSIONS: A high proportion of critically ill patients have IR. There may not be any significant relationship between IR and measures of inflammation, coagulation, and clinical outcomes in a heterogeneous population of critically ill patients.  相似文献   
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Nucleostemin (NS) is implicated in the control of stem and cancer cell proliferation. In the present study, we have examined the expression of NS and its spliced variants in various brain tumors. Total RNA was extracted from 59 brain tumor samples, and the expression of different NS spliced variants was measured by semi‐quantitative RT‐PCR. The subcellular distribution of NS protein in brain tumors was further examined by immunohistochemistry. Furthermore, to decipher the potential involvement of NS in brain tumorogenesis, its expression was knocked‐down by means of RNA interference (RNAi) in two malignant glioma (U‐87MG and A172), one astrocytoma (1321N1) and one medulloblastoma (DAOY) cell lines. The alterations in cell‐cycle progression of the treated cells were then analyzed by flow cytometry. Our data revealed that NS and its variants are widely expressed in different types of brain tumors. Among the NS spliced variants, variant “1” and variant “3” were detected in the majority of tumor samples, whereas variant “2” was only detectable in few samples. Moreover, the intensity of the expression was correlated with the grade of the tumors (P < 0.05). Accordingly, the expression was much higher in glial tumors compared to that of meningiomas. As expected, a nucleolar/nucleoplasmic localization of NS protein was observed in the examined tumor samples. RNAi results revealed a significant reduction of NS expression along with a moderate blockade of the cell cycle in G2/M and S phases of NS‐siRNA treated cells. All in all, our data suggest a potential role for NS in tumorogenesis of brain cancers. © 2010 Wiley‐Liss, Inc.  相似文献   
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We report a case of life-threatening hematemesis due to portal hypertension caused by an isolated arterioportal fistula (APF). Intrahepatic APFs are extremely rare and are a cause of presinusoidal portal hypertension. Etiologies for APFs are comprised of precipitating trauma, malignancy, and hereditary hemorrhagic telangiectasia, but these were not the case in our patient. Idiopathic APFs are usually due to congenital vascular abnormalities and thus usually present in the pediatric setting. This is one of the first cases of adult-onset isolated APF who presented with portal hypertension and was successfully managed through endoscopic hemostasis and subsequent interventional radiological embolization.  相似文献   
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