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991.
Despite substantial improvements in head and neck squamous cell carcinoma (HNSCC) treatment, the major obstacle to long‐term survival remains disease recurrence. Salvage options are often limited due to prior therapy and the escalated morbidity of retreatment. The costs of treatment must be measured against the anticipated quality and quantity of life recovered, even with resectable disease. This review surveys the recurrent HNSCC literature to better guide decision making. Across multiple studies, negative prognostic factors include impaired performance status, advanced recurrent stage, brief disease‐free interval, previous chemotherapy, and nonlaryngeal sites of recurrence. When possible, surgical salvage remains the principal option for durable disease control, quality of life preservation, and cure. Nonsurgical therapies have also demonstrated measurable improvements in locoregional control. Interpretation of salvage literature must be tempered by recognition of significant selection bias. The decision for salvage therapy must be individualized, with management that involves well‐informed patients resulting in the best outcomes. © 2013 Wiley Periodicals, Inc. Head Neck 36 : 144–151, 2014  相似文献   
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Data have emerged that the addition of concurrent chemotherapy to radiation can lead to swallowing dysfunction that may have an impact on patient quality of life and lead to significant morbidities such as poor nutritional status, enteral feeding tube dependence, and aspiration pneumonia. Although intensity‐modulated radiation therapy (IMRT) for head and neck cancer was initially developed to spare the parotid gland to reduce xerostomia, attention has recently focused on its utility to selectively decrease radiation dose to specified anatomic structures responsible for a functional swallow. Recent reports have proposed a variety of dose thresholds or constraints to these swallowing‐related structures, which may guide IMRT planning with the aim of reducing dysphagia. This critical review of the current literature assesses the feasibility of IMRT to maintain swallowing function and appraises the various dosimetric parameters that have been proposed to help minimize long‐term dysphagia. © 2013 Wiley Periodicals, Inc. Head Neck 36: 291–298, 2014  相似文献   
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GTP cyclohydrolase (GCH1) is rate limiting for tetrahydrobiopterin (BH4) synthesis, where BH4 is a cofactor for nitric oxide (NO) synthases and aromatic hydroxylases. GCH1 polymorphisms are implicated in the pathophysiology of pain, but have not been investigated in African populations. We examined GCH1 and pain in sickle cell anemia where GCH1 rs8007267 was a risk factor for pain crises in discovery (n = 228; odds ratio [OR] 2.26; P = 0.009) and replication (n = 513; OR 2.23; P = 0.004) cohorts. In vitro, cells from sickle cell anemia subjects homozygous for the risk allele produced higher BH4. In vivo physiological studies of traits likely to be modulated by GCH1 showed rs8007267 is associated with altered endothelial dependent blood flow in females with SCA (8.42% of variation; P = 0.002). The GCH1 pain association is attributable to an African haplotype with where its sickle cell anemia pain association is limited to females (OR 2.69; 95% CI 1.21–5.94; P = 0.01) and has the opposite directional association described in Europeans independent of global admixture. The presence of a GCH1 haplotype with high BH4 in populations of African ancestry could explain the association of rs8007267 with sickle cell anemia pain crises. The vascular effects of GCH1 and BH4 may also have broader implications for cardiovascular disease in populations of African ancestry. Am. J. Hematol. 89:187–193, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   
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Iron deficiency anemia (IDA) is the most common form of anemia worldwide. Although oral iron is used as first‐line treatment, many patients are unresponsive to or cannot take oral iron. This Phase III, open‐label, non‐inferiority study compared the efficacy and safety of ferumoxytol, a rapid, injectable intravenous (IV) iron product with low immunological reactivity and minimal detectable free iron, with IV iron sucrose in adults with IDA of any cause. Patients (N = 605) were randomized 2:1 to receive ferumoxytol (n = 406, two doses of 510 mg 5 ± 3 days apart) or iron sucrose (n = 199, five doses of 200 mg on five nonconsecutive days over 14 days) and followed for 5 weeks. Ferumoxytol demonstrated noninferiority to iron sucrose at the primary endpoint, the proportion of patients achieving a hemoglobin increase of ≥2 g dL?1 at any time from Baseline to Week 5 (ferumoxytol, 84.0% [n = 406] vs. iron sucrose, 81.4% [n = 199]), with a noninferiority margin of 15%. Ferumoxytol was superior to iron sucrose (2.7 g dL?1 vs. 2.4 g dL?1) in the mean change in hemoglobin from Baseline to Week 5 (the alternative preplanned primary endpoint) with P = 0.0124. Transferrin saturation, quality‐of‐life measures, and safety outcomes were similar between the two treatment groups. Overall, ferumoxytol demonstrated comparable safety and efficacy to iron sucrose, suggesting that ferumoxytol may be a useful treatment option for patients with IDA in whom oral iron was unsatisfactory or could not be used. Am. J. Hematol. 89:646–650, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   
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Children with sickle cell anemia have a higher‐than‐expected prevalence of poor educational attainment. We test two key hypotheses about educational attainment among students with sickle cell anemia, as measured by grade retention and use of special education services: (1) lower household per capita income is associated with lower educational attainment; (2) the presence of a silent cerebral infarct is associated with lower educational attainment. We conducted a multicenter, cross‐sectional study of cases from 22 U.S. sites included in the Silent Infarct Transfusion Trial. During screening, parents completed a questionnaire that included sociodemographic information and details of their child's academic status. Of 835 students, 670 were evaluable; 536 had data on all covariates and were used for analysis. The students' mean age was 9.4 years (range: 5–15) with 52.2% male; 17.5% of students were retained one grade level and 18.3% received special education services. A multiple variable logistic regression model identified that lower household per capita income (odds ratio [OR] of quartile 1 = 6.36, OR of quartile 2 = 4.7, OR of quartile 3 = 3.87; P = 0.001 for linear trend), age (OR = 1.3; P < 0.001), and male gender (OR, 2.2; P = 0.001) were associated with grade retention; silent cerebral infarct (P = 0.31) and painful episodes (P = 0.60) were not. Among students with sickle cell anemia, household per capita income is associated with grade retention, whereas the presence of a silent cerebral infarct is not. Future educational interventions will need to address both the medical and socioeconomic issues that affect students with sickle cell anemia. Am. J. Hematol. 89:E188–E192, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   
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