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BACKGROUND:

Some evidence suggests that women with pregnancy‐associated breast cancers (PABC) have a worse outcome compared with historical controls. However, young age is a worse prognostic factor independently, and women with PABC tend to be young. The purpose of the current study was to compare locoregional recurrence (LRR), distant metastases (DM), and overall survival (OS) in young patients with PABC and non‐PABC.

METHODS:

Data for 668 breast cancers in 652 patients aged ≤35 years were retrospectively reviewed. One hundred four breast cancers (15.6%) were pregnancy‐associated; 51 cancers developed during pregnancy and 53 within 1 year after pregnancy.

RESULTS:

The median follow‐up for all living patients was 114 months. Patients who developed PABC had more advanced T classification, N classification, and stage group (all P < .04) compared with patients with non‐PABC. Patients with PABC had no statistically significant differences in 10‐year rates of LRR (23.4% vs 19.2%; P = .47), DM (45.1% vs 38.9%; P = .40), or OS (64.6% vs 64.8%; P = .60) compared with patients with non‐PABC. For those patients who developed breast cancer during pregnancy, any treatment intervention during pregnancy provided a trend toward improved OS compared with delaying evaluation and treatment until after delivery (78.7% vs 44.7%; P = .068).

CONCLUSIONS:

Young patients with PABC had no statistically significant differences in LRR, DM, or OS compared with those with non‐PABC; however, pregnancy contributed to a delay in breast cancer diagnosis, evaluation, and treatment. Primary care and reproductive physicians should be aggressive in the workup of breast symptoms in the pregnant population to expedite diagnosis and allow multidisciplinary treatment. Cancer 2009. © 2009 American Cancer Society.  相似文献   
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Quadros  EV; Sai  P; Rothenberg  SP 《Blood》1993,81(5):1239-1245
Transcobalamin II (TCII) is a cobalamin (Cbl, vitamin B12)-binding protein in mammalian plasma that facilitates the cellular uptake of the vitamin. To obtain human TCII in sufficient quantity for analytical studies, the complementary DNA (cDNA) encoding TCII was inserted into the plasmid PVL 1393, and the baculovirus expressing TCII was obtained by homologous recombination in Spodoptera frugiperda (SF9) insect cells by cotransfection with the wildtype virus. Under optimized conditions, SF9 cells infected with the recombinant virus secreted 2 to 4 micrograms of TCII per milliliter of culture medium. TCII did not accumulate in the SF9 cells and seemed to be constitutively secreted as observed previously in cultured human endothelial cells. The purified recombinant TCII has the same molecular weight by SDS-PAGE as purified human TCII. The recombinant TCII cross-reacts with an antiserum to native human TCII, binds Cbl and facilitates the uptake of Cbl in eukaryotic cells by binding to the receptor for TCII-Cbl on the plasma membrane of K562 cells. Amino acid sequence analysis of the purified recombinant TCII identified two polypeptides, one identical to the amino acid sequence deduced from the cDNA and a second lacking the first and second N-terminal residues. These sequences are identical to two TCII polypeptides purified from Cohn fraction III of pooled human plasma. The two forms of recombinant TCII have the same isoelectric points as the two predominant isoprotein forms of TCII in human serum. Since the baculovirus construct contains a single cDNA that can encode only one amino acid sequence, the two isoproteins in recombinant TCII must be generated by a mechanism other than allele specific expression. A plausible mechanism for generating isoproteins of nonglycosylated peptides, such as TCII, may be by splicing of the leader peptide at alternative sites.  相似文献   
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Objective

To predict student performance in an introductory graduate-level biomedical informatics course from application data.

Design

A predictive model built through retrospective review of student records using hierarchical binary logistic regression with half of the sample held back for cross-validation. The model was also validated against student data from a similar course at a second institution.

Measurements

Earning an A grade (Mastery) or a C grade (Failure) in an introductory informatics course.

Results

The authors analyzed 129 student records at the University of Texas School of Health Information Sciences at Houston (SHIS) and 106 at Oregon Health and Science University Department of Medical Informatics and Clinical Epidemiology (DMICE). In the SHIS cross-validation sample, the Graduate Record Exam verbal score (GRE-V) correctly predicted Mastery in 69.4%. Undergraduate grade point average (UGPA) and underrepresented minority status (URMS) predicted 81.6% of Failures. At DMICE, GRE-V, UGPA, and prior graduate degree significantly correlated with Mastery. Only GRE-V was a significant independent predictor of Mastery at both institutions. There were too few URMS students and Failures at DMICE to analyze. Course Mastery strongly predicted program performance defined as final cumulative GPA at SHIS (n = 19, r = 0.634, r2 = 0.40, p = 0.0036) and DMICE (n = 106, r = 0.603, r2 = 0.36, p < 0.001).

Conclusions

The authors identified predictors of performance in an introductory informatics course including GRE-V, UGPA and URMS. Course performance was a very strong predictor of overall program performance. Findings may be useful for selecting students for admission and identifying students at risk for Failure as early as possible.  相似文献   
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Background  

Our objective was to analyze subjective explanations for unsuccessful weight loss among bariatric surgery candidates.  相似文献   
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