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991.
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The database of a major microbiology laboratory in Israel was searched to determine the prevalence of nontuberculous mycobacterial lymphadenitis in immunocompetent children. We observed a 4-fold increase in nontuberculous mycobacteria isolates during 1985-2006, which was attributable mainly to increased detection of Mycobacterium haemophilum starting in 1996.  相似文献   
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Kim HK  Laor T  Racadio JM 《Pediatric radiology》2008,38(12):1300-1305
BACKGROUND: Variations in the lower extremity musculature have been identified, including an anomalous origin of the medial head of the gastrocnemius muscle. Anomalies of the lateral head of the gastrocnemius muscle (LGN) have been less frequently described, especially in children. OBJECTIVE: To describe the MR imaging appearance, frequency and clinical symptoms associated with anatomic variations of the LGN in children and young adults. MATERIALS AND METHODS: A retrospective review of 465 knee MR imaging examinations was performed. The site of origin of the LGN was identified as either normal, lateral segmental anomalous origin (LSAO), or medial accessory anomalous origin (MAAO). The clinical indication for imaging was recorded. RESULTS: An anatomic variation of the LGN was identified in 16 patients (3.4%). Nine patients had LSAO, and five of these had symptoms referable to or abnormalities of the patella. Seven patients had MAAO, and three of these had chronic nontraumatic knee pain. CONCLUSION: Anatomic variations of the LGN are not rare in young patients, occurring with a frequency of 3.4% in our series. It is unknown whether these anomalies play a role in the etiology of patellofemoral pain or unexplained joint pain in children.  相似文献   
995.
Gene expression-based prediction of genomic copy number aberrations in the chromosomal region 12q13 to 12q15 that is flanked by MDM2 and CDK4 identified Wnt inhibitory factor 1 (WIF1) as a candidate tumor suppressor gene in glioblastoma. WIF1 encodes a secreted Wnt antagonist and was strongly downregulated in most glioblastomas as compared with normal brain, implying deregulation of Wnt signaling, which is associated with cancer. WIF1 silencing was mediated by deletion (7/69, 10%) or epigenetic silencing by promoter hypermethylation (29/110, 26%). Co-amplification of MDM2 and CDK4 that is present in 10% of glioblastomas was associated in most cases with deletion of the whole genomic region enclosed, including the WIF1 locus. This interesting pathogenetic constellation targets the RB and p53 tumor suppressor pathways in tandem, while simultaneously activating oncogenic Wnt signaling. Ectopic expression of WIF1 in glioblastoma cell lines revealed a dose-dependent decrease of Wnt pathway activity. Furthermore, WIF1 expression inhibited cell proliferation in vitro, reduced anchorage-independent growth in soft agar, and completely abolished tumorigenicity in vivo. Interestingly, WIF1 overexpression in glioblastoma cells induced a senescence-like phenotype that was dose dependent. These results provide evidence that WIF1 has tumor suppressing properties. Downregulation of WIF1 in 75% of glioblastomas indicates frequent involvement of aberrant Wnt signaling and, hence, may render glioblastomas sensitive to inhibitors of Wnt signaling, potentially by diverting the tumor cells into a senescence-like state.  相似文献   
996.
In patients with intestinal malrotation, Ladd bands are known to cause obstruction of the duodenum and small bowel. However, acute obstruction of the colon from Ladd bands has not been previously described. We report a case of complete obstruction of the hepatic flexure of the colon secondary to a Ladd band in a previously healthy teenage boy.  相似文献   
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(Headache 2010;50:219‐223) Objective.— To evaluate the effectiveness of nonpharmacologic treatment for migraine in children younger than age 6 years. Background.— The mean age of onset of migraine in children is 7.2 years for boys and 10.9 years for girls. Treatment consists of individually tailored pharmacologic and nonpharmacologic interventions. However, data on migraine management in preschoolers are very sparse. Methods.— Demographic, clinical, and outcome data were collected from the files of patients with migraine who attended a pediatric headache clinic. Only those treated by nonpharmacologic measures, namely, good sleep hygiene, diet free of food additives, and limited sun exposure, were included. Clinical factors and response to treatment were compared between children younger than 6 years and older children. Results.— Of the 92 children identified, 32 were younger than 6 years and 60 were older. There was no difference between the age groups in most of the demographic and clinical parameters. The younger group was characterized by a significantly lower frequency of migraine attacks and shorter disease duration (in months). Mean age of the patients with no response to treatment (grade 1) was 10.588 ± 3.254 years; partial response (grade 2), 9.11 ± 4.6 years; and complete response (grade 3), 8.11 ± 3.93 years (P = .02). The percentage of patients with complete to partial response as opposed to no response was significantly higher in the younger group (P = .00075). Conclusion.— As the primary option, conservative therapy for migraine appears to be more effective in children younger than 6 years than in older children, perhaps because of their shorter duration of disease until treatment and lower frequency of attacks.  相似文献   
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