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991.
In a retrospective study using univariate analysis, we identified tumor type (nonendometrioid vs endometrioid), depth of myoinvasion (MI), mode of MI (infiltrative vs cohesive), and direct anatomic invasion of the cervical wall from the isthmus as significant positive risk factors for intramyometrial lymphvascular space involvement (LVSI). On multivariate analysis, tumor grade, depth of MI, and mode of MI retained their significance. We created a grid for the relative risks of LVSI with respect to these variables individually or in combination. We suggest that our indirect estimate of the risk of LVSI can help in assessing prognosis and determining the need for adjuvant therapy whenever LVSI is important in clinical decision making, but its pathologic diagnosis is uncertain.  相似文献   
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993.
The main objectives of the European Committee on Antimicrobial Susceptibility Testing (EUCAST) are to harmonise breakpoints for antimicrobial agents in Europe, and to act as the breakpoint committee for the European Medicines Agency (EMEA) during the registration of new antimicrobial agents. Detailed EUCAST procedures for harmonising and setting breakpoints for antimicrobial agents are available on the EUCAST website. Beginning with the current issue, a series of EUCAST Technical Notes will be published in CMI, based on the rationale documents produced by EUCAST for each of the antimicrobial agents studied, with the aim of highlighting important background information underlying decisions on breakpoints made by EUCAST.  相似文献   
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Opportunistic infections in the oral cavity of the elderly may increase the incidence of systemic disease. The objective of this study was to investigate the differences in the oral bacterial flora between dependent elderly (inpatients) and independent elderly (community-dwelling residents). After multiple variables were taken into account, inpatients had significantly lower detection rates than community-dwelling residents for alpha-streptococci (p < 0.001) and Neisseria (p 0.004), and higher detection rates for Pseudomonas aeruginosa (p 0.024), methicillin-resistant Staphylococcus aureus (MRSA) (p 0.011) and Actinomyces spp. (p 0.005). Among inpatients, the requirement for a high degree of care was related negatively to detection of alpha-streptococci, but was related significantly to detection of P. aeruginosa (p 0.018) or MRSA (p 0.004). Tube-fed inpatients had a significantly lower detection rate for alpha-streptococci (p 0.041) and a higher detection rate for P. aeruginosa (p 0.004) than those who did not require tube feeding. Inpatients with a history of antibiotic use had a significantly lower detection rate for alpha-streptococci (p 0.049) and a higher detection rate for MRSA (p 0.007) than those without a history of antibiotic use. The detection rates for P. aeruginosa or MRSA in inpatients without alpha-streptococci were higher than in inpatients with alpha-streptococci after controlling for age and gender (P. aeruginosa, p 0.006; MRSA, p 0.001). Overall, detection of alpha-streptococci had an inverse correlation with the detection of P. aeruginosa and MRSA in the oral cavity and is likely to be an indicator of pathogenic bacterial infection.  相似文献   
998.
BACKGROUND: 1Alpha,25-dihydroxyvitamin D(3) [1,25(OH)(2) Vitamin D(3)] induces growth inhibition in squamous cell carcinoma (SCC) cell lines of the head and neck by arresting the cells in the G0/G1 phase of the cell cycle, probably due to an enhanced expression of p21, which could be demonstrated in other cell lines (JPPA, SCC9) before. In SCC25, a SCC cell line isolated from tongue, growth inhibition but no overexpression of p21 was detected. The retinoblastoma gene, as a direct target of G1 cyclin-CDK complexes, showed an obvious shift from the hyperphosphorylated to the hypophosphorylated form under 1,25(OH)(2)Vitamin D(3), which indicates that the growth inhibition takes place in the G0/G1 phase. To explore the possible pathway of growth inhibition in SCC25 we investigated other cell cycle inhibitors (p18, p19, p27). METHODS: Synchronized cells were treated with 1,25(OH)(2)Vitamin D(3) over 96 h. The cell cycle status and expression of cell cycle-regulating proteins was determined by fluorescence-activated cell sorting (FACS) and Western blotting. An overexpression of p18 in 1,25(OH)(2)Vitamin D(3) vs. ethanol-treated cells was determined until 30 h in SCC25. No influence was detectable on the expression of p27 and p19. CONCLUSION: One mechanism by which 1,25(OH)(2)Vitamin D(3) controls cell growth might be the upregulation of p21. As p21 was unsusceptible to 1,25(OH)(2)Vitamin D(3) in SCC25, other inhibiting proteins were necessary to be tested. The proven upregulation of p18 seems to be the responsible step for growth inhibition of 1,25(OH)(2)Vitamin D(3) in SCC25.  相似文献   
999.
CXCL12 and its receptor, CXCR4, are emerging as promising targets for modulating growth, angiogenesis, and metastasis in several human cancers. Indeed, blocking the receptor is sufficient to prevent metastasis and angiogenesis in experimental breast cancer xenografts. Recently, the biological effect of the CXCR4 in pancreatic cancer, one of the most deadly neoplastic diseases, has been reported. However, the molecular mechanism by which CXCR4 contributes to these properties is not completely understood. In this paper, we characterize the signaling pathways activated by CXCR4 in pancreatic cancer. We show that after CXCR4 activation, EGFR becomes tyrosine phosphorylated, and the kinase activity of this receptor, together with the activation of MMPs, Src, and PI3-Kinase, is required for CXCR4-mediated ERK activation. Analysis of this cascade in pancreatic cancer cells revealed that the ERK-mediated pathway regulates genes involved in angiogenesis, such as VEGF, CD44, HIF1α, and IL-8. Furthermore, ERK blockage inhibits the migration and tube formation of endothelial cells induced by CXCL12. Considering that inhibitors for several components of this pathway, including CXCR4 itself, are at different stages of clinical trials, this study provides theoretical justification for the clinical testing of these drugs in pancreatic cancer, thus extending the list of potential targets for treating this dismal disease.  相似文献   
1000.
Uniparental isodisomy (iUPD) is a rare genetic condition caused by non-disjunction during meiosis that ultimately leads to a duplication of either the maternal or paternal chromosome in the affected individual. Two types of disorders can result, those due to imprinted genes and those due to homozygosity of recessive disease-causing mutations. Here, we describe the third known case of complete chromosome 4 iUPD of maternal origin. This condition became apparent during whole genome linkage studies of psychiatric disorders in the Portuguese population. The proband is an adult female with normal fertility and no major medical complaints, but a history of major depressive disorder and multiple suicide attempts. The proband's siblings and parents had normal chromosome 4 genotypes and no history of mood disturbance. A brief review of other studies lends support for the possibility that genes on chromosome 4 might confer risk for mood disorders. We conclude that chromosome 4 maternal uniparental disomy (UPD) is a rare disorder that may present with a major depressive phenotype. The lack of a common disease phenotype between this and two other cases of chromosome 4 iUPD [Lindenbaum et al. [1991] Am J Med Genet 49(Suppl 285):1582; Spena et al. [2004] Eur J Hum Genet 12:891-898) would suggest that there is no vital maternal gene imprinting on chromosome 4. However, since there is no reported case of paternal chromosome 4 UPD, paternal gene imprinting on chromosome 4 cannot be excluded.  相似文献   
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