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Methodological limitations in most previous magnetic resonance imaging (MRI)-based volumetric studies might have contributed to the inconsistent results regarding the frontal lobe regions of schizophrenia. Thus, applying the largest sample to date among those that have fully taken account of the intrinsic anatomical landmarks, this study aimed at clarifying the volumetric alterations of the frontal lobe and its subregions in schizophrenia. Participants comprised 59 patients with schizophrenia and 58 healthy controls. Measurements were performed on consecutive 1-mm-thick coronal slices reformatted from three-dimensional 1.5-T MR images. The whole frontal lobe was demarcated and then subdivided into the precentral gyrus (PCG), anterior cingulate, and posterior cingulate, and the remainder temporarily as the prefrontal region. Patients with schizophrenia had significant cortical volume reductions in the bilateral whole frontal lobe, prefrontal region, PCG, posterior cingulate, and right anterior cingulate. This study has confirmed that patients with schizophrenia do have cortical volume reductions in the whole frontal lobe and its subregions. Volume reduction in the PCG suggests that the primary motor cortex might contribute to the mechanisms of schizophrenia, considering its important role in the processing of multiple motor-related cognitive functioning suggested by the recent literature.  相似文献   
145.
In this study, respiratory-gated ventilation and perfusion single-photon emission tomography (SPET) were used to define regional functional impairment and to obtain reliable co-registration with computed tomography (CT) images in various lung diseases. Using a triple-headed SPET unit and a physiological synchroniser, gated perfusion SPET was performed in a total of 78 patients with different pulmonary diseases, including metastatic nodules (n=15); in 34 of these patients, it was performed in combination with gated technetium-99m Technegas SPET. Projection data were acquired using 60 stops over 120° for each detector. Gated end-inspiration and ungated images were reconstructed from 1/8 data centered at peak inspiration for each regular respiratory cycle and full respiratory cycle data, respectively. Gated images were registered with tidal inspiration CT images using automated three-dimensional (3D) registration software. Registration mismatch was assessed by measuring 3D distance of the centroid of the nine selected round perfusion-defective nodules. Gated SPET images were completed within 29 min, and increased the number of visible ventilation and perfusion defects by 9.7% and 17.2%, respectively, as compared with ungated images; furthermore, lesion-to-normal lung contrast was significantly higher on gated SPET images. In the nine round perfusion-defective nodules, gated images yielded a significantly better SPET-CT match compared with ungated images (4.9±3.1 mm vs 19.0±9.1 mm, P<0.001). The co-registered SPET-CT images allowed accurate perception of the location and extent of each ventilation/perfusion defect on the underlying CT anatomy, and characterised the pathophysiology of the various diseases. By reducing respiratory motion effects and enhancing perfusion/ventilation defect clarity, gated SPET can provide reliable co-registered images with CT images to accurately characterise regional functional impairment in various lung diseases.  相似文献   
146.
We reviewed the results of 51 patients with benign bone tumours treated by curettage and implantation of calcium hydroxyapatite ceramic (CHA). The mean follow-up was 11.4 years (10 to 15.5). Post-operative fractures occurred in two patients and three had local recurrences; three had slightly limited movement of the adjacent joint and one had mild osteoarthritis. There were no allergic or neoplastic complications. In all cases, radiographs showed that the CHA was well incorporated into the host bone. Statistical analysis showed that absorption of the implanted CHA was greater in males (odds ratio, 6.2; 95% CI, 1.6 to 23.7) and younger patients (odds ratio, 0.6 for increase in age of 10 years; 95% CI, 0.91 to 0.99). However, the implanted CHA was not completely absorbed in any patient. We conclude that CHA is a useful and safe bone substitute for the treatment of benign bone tumours.  相似文献   
147.
To clarify heterogeneity in Japanese adult-onset type 1 diabetes, we analyzed the HLA-DR and -DQ haplotypes, depending on the clinical phenotype, and compared them with those in childhood-onset type 1 diabetes (CO). The patients in a previously reported Ehime Study were divided into subgroups by the mode of onset of diabetes: 68 acute-onset type 1 diabetic patients (AO) and 28 slowly progressive type 1 diabetic patients (SO). HLA haplotypes were compared with those of 80 CO patients and 190 control subjects. Two major susceptible HLA haplotypes in the Japanese, DRB1*0405-DQB1*0401 (DR4) and DRB1*0901-DQB1*0303 (DR9), were significantly increased in the AO and CO groups, but only DR9 was increased in the SO group. AO subjects had a higher frequency of DR9 than CO subjects. Accordingly, the DR9:DR4 frequency increased with increasing age of onset. Another susceptible haplotype, DRB1*0802-DQB1*0302 (DR8), was involved only in the CO group. Analysis of haplotype combinations revealed that DR4 and DR9 had significant dosage effects on the AO and CO groups (P < 0.0001), but only DR9 had such an effect in the SO group (P < 0.03). These results suggest differences in the contribution of HLA class II haplotypes to susceptibility of type 1 diabetes depending on the clinical phenotype and also indicate that HLA class II haplotypes may be associated with the onset age of type 1 diabetes.  相似文献   
148.
Eotaxin is a C-C chemokine that acts to selectively induce local accumulation of eosinophils and basophils. Eotaxin is also believed to be involved in the infiltration of eosinophils in the nasal polyps of patients with chronic sinusitis. However, only a few studies on eotaxin in nasal polyps have been performed. In this study, we investigated the localization of eotaxin in human nasal polyps and the identification of eotaxin-positive cells using immunohistochemistry. The distribution of eotaxin immunoreactivity in the nasal polyps of patients with chronic sinusitis was found to almost coincide with the presence of eosinophils. Eotaxin immunoreactivity was also detected in some vascular endothelial cells. These findings suggest that eotaxin is produced by eosinophils and vascular endothelial cells in nasal polyps and is involved in the accumulation of eosinophils in nasal polyps.  相似文献   
149.
Multislice computed tomography (CT) enables rapid, easy construction of 3-dimensional CT images (3D-CT), aiding diagnostic imaging. 3D-CT is reported to be highly useful in diagnosing temporal bone disorders, in otorhinolaryngology, especially abnormal shape and the ossicular chain of the auditory ossicles and facial bone fractures. Given the complexity of laryngeal anatomy, 3D-CT is useful in diagnosing the extent of infiltration of laryngeal cancer and in examining vocal cord movement, which is difficult to evaluate by conventional CT, magnestic resonance imaging (MRI), and fiberscopy. Among patients seen for a suspected foreign body between June 2002 and May 2003, we chose 3 in whom laryngoscopy at the first examination could not detect a foreign body but in whom symptoms and findings suggested such presence in the paraesophageal orifice. In all 3 cases, 3D-CT imaging showed the size, length, location, and direction of the foreign body, providing information useful for the surgical approach.  相似文献   
150.
We determined the susceptibilities of 265 invasive isolates of pneumococci obtained during 1995 to 2001 in Hong Kong to 11 antimicrobial agents and their serotypes. Overall, 62.6% isolates were susceptible to penicillin, 20% were intermediately resistant, and 17.4% were resistant. The overall prevalence of levofloxacin resistance (MIC > or = 8 microg/mL) was 3.8% but increased to 15.2% among the penicillin-resistant isolates. All levofloxacin-resistant isolates were clonally related; had reduced susceptibility to penicillin, cefotaxime, and clarithromycin; and were derived from adults > or = 50 years of age. Of the penicillin-nonsusceptible pneumococci, 90% from children < or = 5 years of age and 54.8% from persons of all ages were of serotypes that are included in the 7-valent pneumococcal conjugate vaccine; 93.5% from children < or = 5 years of age and 93% from persons of all ages were of serotypes that are included in the 23-valent polysaccharide vaccine.  相似文献   
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