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11.
Ugwumadu AHN, Carmichael P, Neven P. Tamoxifen and the female genital tract. Int J Gynecol Cancer 1998; 8 : 6–15.
Tamoxifen was originally developed by Imperial Chemical Industries (England) (ICI) in 1966 as an anti-estrogenic contraceptive. Ironically, it found a role in the treatment of anovulatory infertility, but its most important application to date is in adjuvant hormonotherapy for breast cancer. Tamoxifen has a complex and poorly understood mix of estrogenic and anti-estrogenic properties with variable and contrasting effects on hormone-sensitive target tissues, such as the endometrium. This article reviews the gynecologic lesions associated with tamoxifen therapy and discusses the merits and acceptability of endometrial surveillance tests and the role of progestogens.  相似文献   
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BACKGROUND: In breast cancer, there is an inverse relationship between HER2/neu overexpression and receptors for estrogen (ER) or progesterone (PR). Some clinical observations such as the age-related association between hormone receptors and tumour grade, which predicts HER2/neu overexpression, suggest an age-related relationship. PATIENTS AND METHODS: Our study population consisted of 1362 consecutive women receiving primary surgery for non-metastatic invasive breast cancer. We compared the relationship between both hormone receptors and HER2/neu overexpression in different age groups taking other tumour characteristics into account. RESULTS: In a multivariate model, considering the overall group, a negative ER, a negative PR and a high tumour grade were predictive for HER2/neu overexpression (P <0.001). Considering 246 women aged < or =45 years, the only predictor for HER2/neu overexpression in this age category was a high tumour grade (P = 0.003). Considering the 1116 women aged >45 years, ER (P = 0.001), PR (P = 0.001) and tumour grade (P <0.001) were associated with HER2/neu (P <0.001). CONCLUSION: Our findings indicate that the association between ER, PR and HER2/neu overexpression varies with age. The hormone receptors are not an independent predictor for the HER2/neu status in young women while they are in elder patients.  相似文献   
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This paper investigates the bond behavior between a bio-aggregate and a cement-based matrix. The experimental evaluation comprised physical, chemical, image, and mechanical characterization of the bio-aggregate. The image analyses about the bio-aggregate’s outer structure provided first insights to understand the particularities of this newly proposed bio-aggregate for use in cementitious materials. A mineral aggregate (granitic rock), largely used as coarse aggregate in the Brazilian civil construction industry, was used as reference. The bond behavior of both aggregates was evaluated via pull-out tests. The results indicated that both aggregates presented a similar linear elastic branch up to each respective peak loads. The peak load magnitude of the mineral aggregate indicated a better chemical adhesion when compared to the bio-aggregate’s. The post-peak behavior, however, indicated a smoother softening branch for the bio-aggregate, corroborated by the microscopy image analyses. Although further investigation is required, the macaúba crushed endocarp was found to be a thriving bio-material to be used as bio-aggregate.  相似文献   
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Background  

Focus group studies are increasingly published in health related journals, but we know little about how researchers use this method, particularly how they determine the number of focus groups to conduct. The methodological literature commonly advises researchers to follow principles of data saturation, although practical advise on how to do this is lacking. Our objectives were firstly, to describe the current status of sample size in focus group studies reported in health journals. Secondly, to assess whether and how researchers explain the number of focus groups they carry out.  相似文献   
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Background

Recent trials suggest that perioperative β-blockade reduces the risk of cardiac events in patients with a risk of myocardial ischemia who are undergoing noncardiac surgery. Patients with diabetes mellitus are at a high-risk for postoperative cardiac morbidity and mortality. They may, therefore, benefit from perioperative β-blockade.

Methods

The Diabetic Postoperative Mortality and Morbidity (DIPOM) trial is an investigator-initiated and -controlled, centrally randomized, double-blind, placebo-controlled, multicenter trial. We compared the effect of metoprolol with placebo on mortality and cardiovascular morbidity rates in patients with diabetes mellitus who were β-blocker naive, ≥40 years old, and undergoing noncardiac surgery. The study drug was given during hospitalization for a maximum of 7 days beginning the evening before surgery. The primary outcome measure is the composite of all-cause mortality, acute myocardial infarction, unstable angina, or congestive heart failure leading to hospitalization or discovered or aggravated during hospitalization. Follow-up involves re-examination of patients at 6 months and collection of mortality and morbidity data via linkage to public databases. The study was powered on the basis of an estimated 30% 1-year event rate in the placebo arm and a 33% relative risk reduction in the metoprolol arm. The median follow-up period was 18 months.

Results

Enrollment started in July 2000 and ended in June 2002. A total of 921 patients were randomized, and 54% of these patients had known cardiac disease, hypertension, or both.

Conclusion

The results of this study may have implications for reduction of perioperative and postoperative risk in patients with diabetes mellitus who are undergoing major noncardiac surgery.  相似文献   
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Structured training in endonasal endoscopic sinus surgery (EESS) and skull base surgery is essential considering serious potential complications. We have developed a detailed concept on training these surgical skills on the lamb’s head. This simple and extremely cheap model offers the possibility of training even more demanding and advanced procedures in human endonasal endoscopic surgery such as: frontal sinus surgery, orbital decompression, cerebrospinal fluid-leak repair followed also by the naso-septal flap, etc. Unfortunately, the sphenoid sinus surgery cannot be practiced since quadrupeds do not have this sinus. Still, despite this anatomical limitation, it seems that the lamb’s head can be very useful even for the surgeons already practicing EESS, but in a limited edition because of a lack of the experience and dexterity. Only after gaining the essential surgical skills of this demanding field it makes sense to go for the expensive trainings on the human cadaveric model.  相似文献   
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