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51.
Benign ulceration of the cecum is an uncommon lesion. Most cases are diagnosed intraoperatively and most authors have advocated right hemicolectomy due to the difficulty in differentiating benign from malignant lesions. Recently colonoscopic diagnosis and conservative treatment have been reported. We describe six cases of cecal ulcer ranging from asymptomatic lesions diagnosed at colonoscopy and healing with conservative management to perforated ulcers with intra-abdominal abscesses requiring right hemicolectomy. A selective approach to patient management is advocated, including stapler wedge cecectomy with frozen section diagnosis to avoid extensive bowel resection and retain the ileocecal valve.  相似文献   
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Photochemically mediated atom transfer radical polymerization of vinyl monomers is successfully activated by ecofriendly heterogeneous mesoporous graphitic carbon nitride (mpg‐C3N4). This method pertains to the use of mpg‐C3N4 as photoactivator for reduction of initially loaded copper(II) species, thus promoting the in situ formation of the copper(I) species. The controlled nature of the polymerizations in both natural sunlight and UV‐light irradiation at ambient temperature is confirmed by the good agreement of the kinetics of the ­polymerization with theoretical values. The light on–off experiments ­demonstrate that polymerizations are clearly initiated and moderated by either UV light or sunlight.

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Cenani–Lenz syndrome (CLS) is a rare autosomal recessive developmental disorder of the limbs. The disorder is characterized by complete syndactyly with metacarpal fusions and/or oligodactyly sometimes accompanied by radioulnar synostosis. The clinical expression is variable and kidney agenesis/hypoplasia, craniofacial dysmorphism and teeth abnormalities are frequent features as well as lower limb involvement. CLS was recently associated with mutations in the low-density lipoprotein receptor-related protein 4 (LRP4) gene and dysregulated canonical WNT signaling. We have identified a large consanguineous Pakistani pedigree with 9 members affected by CLS. The affected individuals present with a consistent expression of the syndrome restricted to the limbs and kidneys. Symptoms from the lower limb are mild or absent and there were no radioulnar synostosis or craniofacial involvement. Genetic analysis using autozygosity mapping and sequencing revealed homozygosity for a novel missense mutation c.2858T > C (p.L953P) in the LRP4 gene. The mutation is located in a region encoding the highly conserved low-density lipoprotein receptor repeat class B domain of LRP4. Our findings add to the genotype–phenotype correlations in CLS and support kidney anomalies as a frequent associated feature.  相似文献   
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Journal of Neurology - The Present study was conducted to systematically review the effect of the melatonin on sleep quality. We summarized evidence from randomized clinical trials (RCTs) that...  相似文献   
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Scarce data exist regarding costs of pediatric heart failure-related hospitalizations (HFRH) or how costs have changed over time. Pediatric HFRH costs, due to advances in management, will have increased significantly over time. A retrospective analysis of Healthcare Cost and Utilization Project Kids’ Inpatient Database was performed on all pediatric HFRH. Inflation-adjusted charges are used as a proxy for cost. There were a total of 33,189 HFRH captured from 2000 to 2009. Median charges per HFRH rose from $35,079 in 2000 to $72,087 in 2009 (p < 0.0001). The greatest median charges were incurred in patients on extracorporeal membrane oxygenation ($442,134 vs $53,998) or ventricular assist devices ($462,647 vs $55,151). Comorbidities, including sepsis ($207,511 vs $48,995), renal failure ($180,624 vs $52,812), stroke ($198,260 vs $54,974) and respiratory failure ($146,200 vs $48,797), were associated with greater charges (p < 0.0001). Comorbidities and use of mechanical support increased over time. After adjusting for these factors, later year remained associated with greater median charges per HFRH (p < 0.0001). From 2000 to 2009, there has been an almost twofold increase in pediatric HFRH charges, after adjustment for inflation. Although comorbidities and use of mechanical support account for some of this increase, later year remained independently associated with greater charges. Further study is needed to understand potential factors driving these higher costs over time and to identify more cost-effective therapies in this population.  相似文献   
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