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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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This study of etoposide in thyroid cancer was designed to determine the activity and toxicity of etoposide in a variety of inoperable, thyroid hormone insensitive, and radio-iodine resistant primary cancers of the thyroid. The patients were required to have an ECOG performance status of at least 3 and no previous exposure to chemotherapy. The etoposide was given at a dose of 140 mg/m2 daily for 3 days and every 3 weeks until progression. The study was closed after 18 months because of poor accrual. There were no responses seen among the 10 patients accrued. The toxicity was primarily hematologic. There was no evidence of activity of etoposide in thyroid carcinoma, although this study lacked significant power because of the poor accrual.  相似文献   
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Despite a high demand for continuing professional education, it is becoming more challenging to provide education in a resource-limited environment that meets the varied needs of learners. The advent of user-friendly, interactive communication technology led the University of British Columbia in Canada to explore the feasibility of developing a web-based distance learning programme shared by undergraduate and practising therapists to address this problem. Potential benefits and challenges of distance learning, undergraduate web-learning, pilot-test results and an assessment of therapists’ interests and needs are profiled.  相似文献   
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Long term chronic calorie restriction (CR) of adult nonhuman primates significantly reduces morbidity and increases median age of death. The present review is focused upon an ongoing study of sustained adult- onset calorie restriction, which has been underway for 15 years. Monkeys, initially calorie restricted at about 10 years of age, are now approximately 25 years old. The median life span of these restricted monkeys is increasing, now exceeding that of ad libitum (AL)-fed monkeys. In our laboratory, maximum life span for AL-fed monkeys appears to be about 40 years. Thus, whether CR can also increase maximal life span, as it does in rodents, cannot be determined for at least another 15 years. The earliest detectable positive benefit on morbidity in these monkeys was previously reported as the prevention of obesity. Current evidence, as reviewed here, suggests that much obesity- associated morbidity is also mitigated by sustained calorie restraint in nonhuman primates. Furthermore, probably because of the prevention of obesity, diabetes has also been prevented. Recent findings include the identification of extraordinary changes in the glycogen synthesis pathway, and on the phosphorylation of glycogen synthase in response to insulin. This calorie restriction-induced prevention of morbidity does not require excessive leanness, but is clearly present when body fat is within the normal range of 10 to 22%, and this is likely to be true in humans as well.   相似文献   
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Aims  The purpose of this study was to (i) describe the weight, weight-related perceptions and lifestyle behaviours of hospital-based nurses, and (ii) explore the relationship of demographic, health, weight and job characteristics with lifestyle behaviours.
Background  The obesity epidemic is widely documented. Worksite initiatives have been advocated. Nurses represent an important part of the hospital workforce and serve as role models when caring for patients.
Methods  A sample of 194 nurses from six hospitals participated in anthropometric measurements and self-administered surveys.
Results  The majority of nurses were overweight and obese, and some were not actively involved in weight management behaviours. Self-reported health, diet and physical activity behaviours were low, although variable by gender, age and shift. Reports of co-worker norms supported low levels of healthy behaviours.
Conclusions  Findings reinforce the need to address the hospital environment and culture as well as individual behaviours for obesity control.
Implications for nursing management  Nurse managers have an opportunity to consider interventions that promote a climate favourable to improved health habits by facilitating and supporting healthy lifestyle choices (nutrition and physical activity) and environmental changes. Such efforts have the potential to increase productivity and morale and decrease work-related disabilities and improve quality of life.  相似文献   
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