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Yang L, Jacobsen KH. A systematic review of the association between breastfeeding and breast cancer. J Womens Health 2008;17:1635–45.  相似文献   
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Since the 1960s, childbirth education advocates have attempted to persuade pregnant women that educational preparation for labor and birth is an essential component of the transition to motherhood. Initially, pregnant women who were seeking unmedicated births as a refuge from the inhumane childbirth treatments of the mid‐20th century embraced this view. However, with the changing childbirth climate, including a growing preference for medicated birth, scheduled inductions, and cesarean sections, attendance has diminished and childbirth education finds itself at a crossroads. Commonly used childbirth education models/organizations and several new emerging models along with the available research literature and recommendations for clinical practice and research are presented.  相似文献   
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BACKGROUND:

Patients with advanced malignancies for whom standard therapy is ineffective may participate in phase 1 trials. To gain a better understanding of the clinical features that could influence benefit versus risk, the authors of this report assessed prognostic factors and survival for patients who were referred to a phase 1 clinic focused primarily on targeted agents.

METHODS:

The medical records of 200 sequential patients who presented to the Phase 1 Clinic at The University of Texas M. D. Anderson Cancer Center were reviewed, and their characteristics and survival were analyzed.

RESULTS:

The median patient age was 58 years (range, 12‐85 years), and 57% of patients were men. The median number of prior therapies was 4. Of 200 patients, 182 were treated on at least 1 phase 1 clinical trial. The median follow‐up of surviving patients was 21 months, and the median overall survival was 9 months (95% confidence interval [CI], 7.4‐10.8). In univariate analysis, the factors that predicted shorter survival were primary tumor in the gastrointestinal tract; a history of thrombosis, liver metastases, and elevated levels of serum lactate dehydrogenase; platelet count; carbohydrate antigen 9 (Ca19‐9) and Ca‐125 levels; aspartate aminotransferase levels, and alkaline phosphatase levels (P < .05 for each). In multivariate analysis, independent factors that predicted shorter survival were a history of thromboembolism (hazard ratio [HR], 2.38; 95% CI, 1.29‐4.39; P = .005), platelets ≥440 × 109/L (HR, 1.72; 95% CI, 1.12‐2.65; P = .014), and the presence of liver metastases (HR, 1.51; 95% CI, 1.09‐2.09; P = .013).

CONCLUSIONS:

Patients who were referred to phase 1 studies had a short median survival (9 months). Patients with thrombocytosis, liver metastases, and a history of thromboembolism had worse outcomes. A prognostic score is proposed. Cancer 2009. © 2009 American Cancer Society.  相似文献   
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Background: Forty percent of patients with colorectal cancer develop mutations in the K-ras gene.Objective: Our objective was to evaluate whether the presence of c-K-ras gene mutations is a useful tumor-response marker in patients with locally advanced rectal cancer treated with preoperative chemoradiotherapy.Material and Methods: Thirty seven patients with locally advanced rectal cancer were treated with preoperative chemoradiotherapy. Four to six weeks later, surgery was performed. Specimens were classified according to the UICC-AJC classification. A segment of the tumor was obtained to analyze specific c-K-ras gene mutations. Restriction fragment length polymorphism (RFLP) and single strand confirmation polymorphism (SSCP) techniques were used with a set of probes to detect specific c-K-ras mutations in codons 12, 13, and 61. The 37 patients were divided into Group A (with mutations) and Group B (without mutations).Results: All 37 patients completed the scheduled treatment. Group A consisted of 12 patients, whose tumors were classified and specific c-K-ras mutations were located as follows: eight in codon 12, two in codon 13, and one in codon 61. Group B consisted of 25 patients. The tumors were classified and there were more early-stage tumors in Group A, whereas in Group B there were more advanced-stage tumors (P 5 .05, respectively). The mean follow-up was 36.2 6 18.3 months. All Group A patients survived, whereas 8 of the 25 patients in Group B died due to progressive metastatic disease. Survival in Group A was 100%, whereas in Group B it was 59% (P 5 .03).Conclusions: The presence of specific c-K-ras mutations is an indicator of tumor response in patients with locally advanced rectal cancer treated with preoperative chemoradiotherapy and surgery. Therefore, responding patients may be more amenable to less radical surgical procedures based on c-K-ras mutations.  相似文献   
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