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991.
BackgroundPulmonary metastasectomy (PM) for breast cancer-derived pulmonary metastasis is controversial. This study aimed to assess the prognostic factors and implication of PM for metastatic breast cancer using a multi-institutional database.MethodsClinical data of 253 females with pulmonary metastasis of breast cancer who underwent PM between 1982 and 2017 were analyzed retrospectively.ResultsThe median patient age was 56 years. The median follow-up period was 5.4 years, and the median disease-free interval (DFI) was 4.8 years. The 5- and 10-year survival rates after PM were 64.9% and 50.4%, respectively, and the median overall survival was 10.1 years. Univariate analysis revealed that the period of PM before 2000, a DFI <36 months, lobectomy/pneumonectomy, large tumor size, and lymph node metastasis were predictive of a worse overall survival. In the multivariate analysis, a DFI <36 months, large tumor size, and lymph node metastasis remained significantly related to overall survival. The 5- and 10-year cancer-specific survival rates after PM were 66.9% and 54.7%, respectively, and the median cancer-specific survival was 13.1 years. Univariate analyses revealed that the period of PM before 2000, DFI <36 months, lobectomy/pneumonectomy, large tumor size, lymph node metastasis, and incomplete resection were predictive of a worse cancer-specific survival. Multivariate analysis confirmed that a DFI <36 months, large tumor size and incomplete resection were significantly related to cancer-specific survival.ConclusionsAs PM has limited efficacy in breast cancer, it should be considered an optional treatment for pulmonary metastasis of breast cancer.  相似文献   
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The complete genome sequences of three strains of Newcastle disease virus (NDV) isolated from vaccinated commercial layer flocks in Japan in the span of three decades were characterized. All strains had genome lengths of 15,192 nucleotides consisting of six genes in the order of 3′-NP–P/V/W–M–F–HN–L-5′. The general genomic characteristics of the Japanese field strains were consistent with previously characterized class II NDV, except for those belonging to early genotypes (genotype I–IV), which lack the six nucleotide insertion at nucleotide positions 1,648–1,653 of the nucleoprotein (NP) gene. Phylogenetic analysis showed that the Japanese strains could be classified into genotypes VIc and VIIe using the complete genome sequence and the complete coding sequence of the fusion (F) gene according to the unified NDV classification system. Characterization of functional domains and neutralizing epitopes of the F and hemagglutinin-neuraminidase (HN) proteins of Japanese field strains revealed a total of 31 amino acid substitutions, as compared to vaccine strains Ishii and B1, which were widely used in Japan. Although virus neutralization (VN) test showed that poor flock immunity due to vaccination failure or partial and non-uniform immunization maybe the major factors involved in the mechanism of breakthrough infection of the Japanese field strains, approximately two to threefold decrease in the VN titers of the field NDV strains possessing a point mutation (E347K or E347G) at the linear epitope of the HN protein was observed, as compared to vaccine strain B1 and field strain 2440/69, which lack the point mutation. This study may be a useful reference in characterizing future ND outbreaks in vaccinated chickens and as a genetic map for future investigations regarding vaccine designs, reverse genetics systems, and development of molecular diagnostic tools to prevent future ND outbreaks in vaccinated poultry flocks.  相似文献   
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