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161.
We assessed somatic alleles of six receptor tyrosine kinase genes mutated in lung adenocarcinoma for oncogenic activity. Five of these genes failed to score in transformation assays; however, novel recurring extracellular domain mutations of the receptor tyrosine kinase gene ERBB2 were potently oncogenic. These ERBB2 extracellular domain mutants were activated by two distinct mechanisms, characterized by elevated C-terminal tail phosphorylation or by covalent dimerization mediated by intermolecular disulfide bond formation. These distinct mechanisms of receptor activation converged upon tyrosine phosphorylation of cellular proteins, impacting cell motility. Survival of Ba/F3 cells transformed to IL-3 independence by the ERBB2 extracellular domain mutants was abrogated by treatment with small-molecule inhibitors of ERBB2, raising the possibility that patients harboring such mutations could benefit from ERBB2-directed therapy.  相似文献   
162.
The access to water and the engineered landscapes accommodating its collection and allocation are pivotal issues for assessing sustainability. Recent mapping, sediment coring, and formal excavation at Tikal, Guatemala, have markedly expanded our understanding of ancient Maya water and land use. Among the landscape and engineering feats identified are the largest ancient dam identified in the Maya area of Central America; the posited manner by which reservoir waters were released; construction of a cofferdam for dredging the largest reservoir at Tikal; the presence of ancient springs linked to the initial colonization of Tikal; the use of sand filtration to cleanse water entering reservoirs; a switching station that facilitated seasonal filling and release; and the deepest rock-cut canal segment in the Maya Lowlands. These engineering achievements were integrated into a system that sustained the urban complex through deep time, and they have implications for sustainable construction and use of water management systems in tropical forest settings worldwide.  相似文献   
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PURPOSE/QUESTION: What is the 2-year estimated implant survival rate of short (<10 mm) dental implants installed in partially edentulous patients? SOURCE OF FUNDING: Information not available. TYPE OF STUDY/DESIGN: Systematic review with meta-analysis of data. LEVEL OF EVIDENCE: Level 1: Good quality, patient-oriented evidence. STRENGTH OF RECOMMENDATION GRADE: Grade B: Inconsistent or limited-quality, patient-oriented evidence.  相似文献   
165.
The LAM2001 phase 3 trial, involving 832 patients with acute myeloid leukemia (AML; median: 46 years) proposed HLA-identical sibling allograft HSCT for all patients with an identified donor. The trial compared reduced-intensity conditioning (RIC) for patients older than 50 years of age (N = 47) and myeloablative conditioning for younger patients (N = 117). BM HSCT was performed in the younger patients, while the older ones received a consolidation course, followed by peripheral blood allo-HSCT using RIC. The incidence of grade II-IV acute GVHD, was 51.9% (95% confidence interval [CI]: 42.1-61.8) and 11.3% (1.6-21.2) after myeloablative or RIC, respectively (P < .0001) and that of chronic GVHD 45.8% (95% CI: 34.8-56.7) and 41.7% (24.7-58.6; NS). Cumulative incidence of nonrelapse mortality at 108 months was 15.8% (95% CI: 9.8-23.2) for myeloablative, and 6.5% (0.2-16.2) for RIC (NS). CI of relapse at 108 months was 21.7% (95% CI: 13.9-28.6) and 28.6% (16.5-43.4; NS). Overall survival at 108 months was 63.4% (95% CI: 54.6-72.2) and 65.8% (52.2-72.2), respectively, after myeloablative or RIC (NS). RIC peripheral blood stem cell allo-HSCT is prospectively feasible for patients between the ages of 51 and 60 years without excess of relapse or nonrelapse mortality, and compares favorably with myeloablative marrow allo-HSCT proposed to younger patients.  相似文献   
166.
Federal legislation placed comparative effectiveness research and patient-centered outcomes research at the center of current and future national investments in health care research. The role of this research in emergency care has not been well described. This article proposes an agenda for researchers and health care providers to consider comparative effectiveness research and patient-centered outcomes research methods and results to improve the care for patients who seek, use, and require emergency care. This objective will be accomplished by (1) exploring the definitions, frameworks, and nomenclature for comparative effectiveness research and patient-centered outcomes research; (2) describing a conceptual model for comparative effectiveness research in emergency care; (3) identifying specific opportunities and examples of emergency care-related comparative effectiveness research; and (4) categorizing current and planned funding for comparative effectiveness research and patient-centered outcomes research that can include emergency care delivery.  相似文献   
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Recent evidence indicates that a sexually dimorphic feature of humans, the facial width-to-height ratio (FWHR), is positively correlated with reactive aggression, particularly in men. Also, predictions about the aggressive tendencies of others faithfully map onto FWHR in the absence of explicit awareness of this metric. Here, we provide the first evidence that amygdala reactivity to social signals of interpersonal challenge may underlie the link between aggression and the FWHR. Specifically, amygdala reactivity to angry faces was positively correlated with aggression, but only among men with relatively large FWHRs. The patterns of association were specific to angry facial expressions and unique to men. These links may reflect the common influence of pubertal testosterone on craniofacial growth and development of neural circuitry underlying aggression. Amygdala reactivity may also represent a plausible pathway through which FWHR may have evolved to represent an honest indicator of conspecific threat, namely by reflecting the responsiveness of neural circuitry mediating aggressive behavior.  相似文献   
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