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91.
We compared early-onset and late-onset obsessive-compulsive disorder (OCD) patients in terms of demographic and clinical features. One hundred sixteen outpatients whose primary diagnosis was OCD according to DSM-IV diagnostic criteria were recruited. Early-onset (n=50) and late-onset (n=66) OCD groups were compared with respect to demographic variables and scores obtained on various scales. A male gender predominance was found in early-onset OCD group. Symmetry/exactness obsessions, religious obsessions, hoarding/saving obsessions, and hoarding/collecting compulsions also were significantly more frequent in the early-onset group than in the late-onset group. The results may suggest a phenotypic difference between the two groups. Further studies are needed to investigate the differences between early-onset and late-onset OCD groups to examine the hypothesis that early-onset OCD is a distinct subtype of the disorder.  相似文献   
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OBJECTIVES: The aim of this study was to evaluate the significance of p53 expression and proliferative activity of glandular epithelium and intestinal metaplasia in Helicobacter pylori associated gastritis of pediatric patients. METHODS: The study included endoscopic gastric biopsies of 54 children with dyspeptic complaints. Immunohistochemistry was performed for evaluation of p53 expression and Ki-67 labeling index, an indicator of proliferative activity. Grading of H. pylori density, intestinal metaplasia and inflammatory cell infiltration were performed in histologic tissue sections stained with hematoxylin-eosin, Giemsa and Alcian-blue. RESULTS: Of 54 children, 35 (64%) were infected by H. pylori. Positive immunostaining for p53 was observed in 11 of 54 cases (20.4%). H. pylori infection was found in 10 (91%) of the p53-positive patients. There was a positive correlation between H. pylori density and Ki-67 labeling index in H. pylori infected children. H. pylori density, Ki-67 labeling index and inflammatory cell infiltration in the p53-positive group were significantly higher than in the p53-negative group. Although intestinal metaplasia was more common in H. pylori infected children (n = 11; 31.4%), there was no difference in the rate of intestinal metaplasia between the p53-positive and p53-negative groups. CONCLUSIONS: The present study shows that p53 mutations and higher proliferative activity of glandular epithelium may be related to H. pylori associated gastritis in children. Because p53 mutation does not appear to be associated with intestinal metaplasia, a precursor for gastric cancer in adults, we think that H.pylori associated p53 alterations do not initiate and promote gastric cancer that may occur in adulthood.  相似文献   
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OBJECTIVE: Our aims were to evaluate the detectability, configuration, location, and dimensions of the cisterna chyli on heavily T2-weighted images obtained with a single-shot fast spin-echo technique and to determine whether the disorders that have the potential to affect the abdominal lymphatic drainage could change the cisternal dimensions. MATERIALS AND METHODS: Thin-collimated axial and coronal images that were originally obtained for MR cholangiopancreatography in 125 patients were reviewed by three observers individually for the presence of abdominal lymphatic confluence. The configuration, location, and dimensions of hyperintense ductal or saccular structures immediately anterior to the vertebral bodies below the diaphragma were recorded. The differences between the mean values of the diameters of the cisterna chyli obtained in the control group and in groups in which lymphatic drainage was expected to be abnormally high were compared using a one-way analysis of variance test. RESULTS: Abdominal confluence of the lymphatics was shown in 96% of patients. The most common configuration of the cisterna chyli was tubular (42.5%). It was located at the level of L1-2 in 33% of cases and at the midline in 70%. Mean longitudinal, anteroposterior, and transverse diameters of the duct were 33.45 +/- 1.74 (SD) mm, 5.23 +/- 0.13 mm, and 5.23 +/- 0.15 mm, respectively. No significant difference was found in the mean values of antero-posterior, transverse, and longitudinal diameters of the cisterna chyli in the control group and in the groups expected to have an increased flow into the cisterna chyli. CONCLUSION: Abdominal confluence of lymphatics seems to be present on most of the heavily T2-weighted images. Its morphologic details and extensions can be visualized on images reconstructed with a maximum-intensity-projection algorithm. Any disorder does not necessarily lead to dilatation of these lymphatic structures.  相似文献   
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Experimental sinusitis in a rhinogenic model   总被引:3,自引:0,他引:3  
OBJECTIVES/HYPOTHESIS: The objectives were to determine the optimal sinusitis induction period and to examine microbiological and histopathological changes of sinusitis recovery stage in a rhinogenic sinusitis model. METHODS: A synthetic sponge was inserted into the right-side nasal cavities of rabbits. The sponge was impregnated with a Streptococcus pneumoniae strain in group 1 and with sterile saline solution in groups 2 and 3. After the fourth day of sponge insertion, sinuses were examined by coronal computed tomography scans at two-day intervals until any radiological evidence of sinusitis was observed. When sinusitis was detected radiologically, five rabbits each from groups 1 and 2 were killed for histological examination. To determine the recovery period of sinusitis, sponges were removed from the rest of the rabbits in groups 1 and 2. Rabbits were selected randomly and killed on the 15th and the 30th days of the recovery period, immediately after radiological examinations. Group 3 was considered a sham group. RESULTS: Sinusitis induction was performed in all rabbits in groups 1 and 2 until the 8th day. After the sponges were removed, inflammation persisted until the 30th day of the study. CONCLUSION: In a rhinogenic sinusitis model, although histological features of sinusitis were demonstrated, further studies are required to standardize this model and to examine whether or not the studied bacterial strain spreads from nasal cavity into sinus.  相似文献   
98.
BACKGROUND AND PURPOSE: Subarachnoid hemorrhage (SAH) constitutes an important neurologic emergency. Some authors have suggested that fluid-attenuated inversion recovery (FLAIR) MR imaging can detect SAH that may not be apparent on CT scans but may be revealed by lumbar puncture. We sought to determine how often FLAIR MR imaging findings are positive for SAH in cases with negative CT findings and positive lumbar puncture results. METHODS: The CT scans and FLAIR MR images of all patients with suspected SAH during a 3-year interval (2000-2002) were retrospectively reviewed by a blinded reader. Among these cases, we identified 12 with CT findings that were negative for SAH, lumbar puncture results that were positive for SAH, and FLAIR MR imaging findings that were available for review. Eleven of the 12 patients had undergone FLAIR MR imaging within 2 days of CT and lumbar puncture. The 12 patients with negative CT findings were comprised of six male and six female patients with an age range of 7 to 69 years. We evaluated the true and false negative and positive FLAIR MR imaging findings for SAH by using the lumbar puncture results as the gold standard. The FLAIR MR imaging findings of 12 additional patients without SAH (as revealed by lumbar puncture) were used as control data for a blinded reading. RESULTS: For all 12 control cases without SAH, the FLAIR MR imaging findings were interpreted correctly. Of the 12 cases that had positive lumbar puncture results but false-negative CT findings for SAH, FLAIR MR imaging findings were true-positive in only two cases and were false-negative in 10. One of the two true-positive cases had the highest concentration of RBC in the series (365 k/cc), and the other had the second highest value of RBC (65 k/cc). CONCLUSION: FLAIR MR imaging cannot replace lumbar puncture to detect the presence of SAH. FLAIR MR imaging findings are infrequently positive (16.7%) when CT findings are negative for SAH. This is likely because there is a minimum concentration of RBC/cc that must be exceeded for CSF to become hyperintense on FLAIR MR images.  相似文献   
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HYPOTHESIS: This study was conducted to compare the effectiveness of two anti-adhesive barriers (Seprafilm and Interceed) for reducing adhesions after thyroidectomy in a rat model. The anti-adhesive barriers are suggested for use in repeated surgeries in general and the gynecologic fields in particular. STUDY DESIGN: Controlled, randomized study. METHODS: Twenty-eight male Wistar Albino rats that underwent right subtotal thyroidectomy were randomly assigned to three groups. One group received Seprafilm (n = 10), and the other received Interceed (n = 10) as anti-adhesive barriers. The third group was the control group (n = 8). At postoperative day 14, the rats were killed under general anesthesia, and the surgical fields were evaluated for the adhesion formation. The extent of the adhesion formation is scored from 0 (no adhesions) to 2 (fibrous adhesions that required sharp dissection). Histopathologically, chronic inflammation, histiocyte, fibroblast, fibrosis, collagen, vascularization, granuloma, giant cell, and fat necrosis were examined. RESULTS: All the subjects in the control group, 7 of 10 in the Interceed group, and 4 of 10 in the Seprafilm group needed to be dissected bluntly or sharply. There was significant difference between the Seprafilm and the control group (P < .05) whereas there was no significant difference between the Interceed group and the control group (P > .05). When examined histopathologically, the criteria showing adhesion, such as fibrosis, fibroblast, and collagen were higher in the control group compared with the Seprafilm and Interceed groups. There was no significant difference between the Seprafilm and Interceed groups, whereas a significant difference was found between these two groups and the control group. CONCLUSION: This study suggests that both Seprafilm and Interceed decrease the incidence of posthyroidectomy adhesions in a rat model. Both agents showed no foreign body reaction.  相似文献   
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