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CONTEXT: The pathology of small bowel obstruction in Crohn disease has not been studied extensively. Stricture formation has been attributed mainly to fibrosis, although muscularization of the submucosa has been discussed previously. OBJECTIVE: To identify additional pathologic changes in Crohn disease that could be involved in the formation of strictures. DESIGN: We reviewed 50 ileal resections from patients with Crohn disease. The histopathologic slides were reviewed initially without knowledge of the macroscopic or clinical findings. We identified an unusual muscular proliferation that we refer to as obliterative muscularization of the submucosa, defined as a thick and continuous muscle layer from the mucosal base to the muscularis propria that is at least 1 cm in length. Subsequently, histopathologic findings were correlated with macroscopic and clinical findings. RESULTS: Obliterative muscularization of the submucosa was present in 14 specimens, and in 11 of these 14 it was topographically restricted to strictures. Submucosal fibrosis was observed in sections from adjacent regions. Obliterative muscularization of the submucosa, including thick-walled vessels and hyperplastic nerves but not prominent scarring, was more common in specimens with strictures; the difference was statistically significant (P <.001). CONCLUSIONS: Obliterative muscularization of the submucosa may be pathogenetically involved in the formation of strictures either directly by causing a sustained spasm, or indirectly by minimizing the vasoprotective role of the submucosa, impairing repair and enhancing scarring.  相似文献   
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Hereditary hearing impairment affects about 1 in 1000 newborns. In most cases hearing loss is non-syndromic with no other clinical features, while in other families deafness is associated with specific clinical abnormalities. Analysis of large families with non-syndromic and syndromic deafness have been used to identify genes or gene locations that cause hearing impairment. The present report describes a large Norwegian family with autosomal dominant non-syndromic, progressive high tone hearing loss with linkage to 1q21-q23. A maximum LOD score of 7.65 (theta = 0.00) was obtained with the microsatellite marker D1S196. Analysis of recombinant individuals maps the deafness gene (DFNA7) to a 22 cM region between D1S104 and D1S466. The region contains several attractive candidate genes. This report supports the idea of extensive genetic heterogeneity in hereditary hearing impairment and represents the first localization of a deafness gene in a Norwegian family.   相似文献   
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Sixteen patients with suspected cerebral metastases were studied with magnetic resonance (MR) imaging before and after the intravenous administration of 0.1 mmol/kg of gadolinium diethylenetriaminepenta-acetic acid. The images were interpreted blindly by two neuroradiologists; all clinical, radiologic (computed tomographic and MR imaging), and pathologic data were reviewed to arrive at a final "best diagnosis," which was then compared with the prior blinded interpretations. Of seven patients found to have multiple metastases, six (86%) had at least one tumor nodule depicted by postinfusion MR imaging that was missed by one or both observers on review of preinfusion images alone. Lesions missed on preinfusion studies were usually small nodules hidden by or not detected next to regions of high-signal edema thought to be related to the adjacent tumor nodule. The authors believe that contrast enhancement improves detection of metastatic foci with MR imaging and that the findings indicate broader implications for the detection of multiple lesions from other causes.  相似文献   
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Inguinal hernias are amongst the most common conditions requiring general surgical intervention. For decades, the preferred approach was the open repair. As laparoscopy became more popular and available and more surgeons became familiarized with this modality, laparoscopic inguinal hernia repair became an alternative. The aim of this study is to assess the effectiveness of laparoscopic inguinal repair, with a focus on bilateral inguinal hernias. Initial reports have shown promising clinical outcomes compared to those of conventional repair of bilateral hernias. However, there are only a few studies concerning laparoscopic repair of bilateral hernias. It is yet to be proven that laparoscopy is the “gold standard” in the treatment of bilateral inguinal hernias. So far, the choice of an inguinal hernia repair technique has been up to each surgeon, depending on their expertise and available resources after taking into consideration each patient’s needs.  相似文献   
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A population based hybrid design combining element of cohort and cross-sectional approach was used to develop a simple clinical algorithm to predict individual probability of developing hypertension (systolic BP > 140 mm Hg and/or diastolic BP > 90 mmHg). 3615 soldiers initially normotensive at the time of induction into high altitude, were studied by systematic random sampling. Multiple logistic regression analysis showed a high significant association between hypertension and age, body mass index (BMI), tobacco smoking and alcohol consumption. Using the constant/coefficient values obtained from the logistic model and the receiver operating characteristics (ROC) curve analysis, the following predictive rule was developed – To the age in years, add (BMIx 3.86); also add 5.53 if he is a smoker; and add 19.81 if he consumes alcohol. If the total exceeds 142, the individual is at high risk of developing hypertension. This algorithm carries a sensitivity of 68.2% and specificity of 78.5%.KEY WORDS: Hypertension, High altitude  相似文献   
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Mycoplasma pneumoniae infections usually produce respiratory symptoms, that only exceptionally involve the nervous system. In this case, the infection generally causes an encephalitic picture characterized by impaired consciousness and seizures, and by normal or non-specific neuroradiological findings. However, four cases of M. pneumoniae infection associated with symmetrical lesions in the putamen and its external surrounding areas, and with extrapiramidal symptoms, have been recently published. We present the case of a patient with a clinical picture characterized by confusion, fever, and seizures, associated with a M. pneumoniae infection. The MRI study showed two symmetrical lesions that involved the areas just outside the putamen and disappeared coinciding with her clinical improvement. The present case would support that the encephalopathy associated with the M. pneumoniae infection shows a tendency to involve a particular region of the brain. Our case might represent the minimal expression of these characteristic lesions, which in the most benign cases would involve the areas immediately outside the putamen, and in other instances the putamen as well.  相似文献   
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