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991.

Background  

From 1968 to 2002, Singapore experienced an almost three-fold increase in breast cancer incidence. This increase appeared to be different across the three main ethnic groups: Chinese, Malays and Indians. This paper used age-period-cohort (APC) modelling, to determine the effects of age at diagnosis, calendar period, and birth cohort on breast cancer incidence for each ethnic group.  相似文献   
992.
PURPOSE: Because radiotherapy exerts cytotoxic effects via generation of massive oxidative stress, we hypothesized that catalase, manganese superoxide dismutase, myeloperoxidase (MPO), and endothelial nitric oxide synthase (eNOS) genotypes might result in greater risk of radiotoxicity. EXPERIMENTAL DESIGN: Cases (n = 446) were Caucasian women with breast cancer who received radiotherapy following lumpectomy. Genotypes were determined by matrix-assisted laser desorption/ionization time-of-flight. The development of acute reactions (moist desquamation) associated with genotypes was modeled using the Cox proportional hazards model, accounting for cumulative biologically effective radiation dose. RESULTS: Genotypes associated with higher levels of reactive oxygen species (ROS) were not associated with risk of radiotoxicity. However, relationships between overweight/obesity [body mass index (BMI), >25] and radiotoxicity risk seemed to be modified by eNOS and MPO genotypes associated with higher generation of nitric oxide and ROS, respectively. Women with high BMI (>25) and eNOS GG genotypes were at more than a 6-fold increase in risk (hazard ratio, 6.39; 95% confidence interval, 2.53-16.15) compared with those with BMI <25, and for MPO, those with high BMI (>25) and GG genotypes also had greater risk of radiotoxicity (hazard ratio, 3.61; 95% confidence interval, 1.78-7.35) compared with those with BMI <25. Overweight/obesity was not a strong risk factor among women with other eNOS and MPO genotypes. Exploratory analysis using classification and regression trees indicated that total number of risk alleles contributed, in part, to acute toxicity outcomes among a subgroup of women. CONCLUSIONS: Associations between BMI and radiotoxicity risk may be most apparent among women with genotypes related to higher levels of oxidative stress. Regression trees may be useful in future studies to examine the contributions of multiple factors to individual susceptibility to adverse effects of cancer treatment.  相似文献   
993.
This study was conducted to establish clinicians’ perspectives of a set of radiology curriculum topics for medical student teaching, which were held to be important by radiologists. A questionnaire was sent to clinicians in all specialties. Forty‐six clinicians (51.1%) out of 90 returned the questionnaires. All curriculum topics were scored above an average of 4 (agree). The five highest ranking curriculum topics in order of importance were: developing a system for viewing chest radiographs (5.59), developing a system for viewing abdominal radiographs (5.56), developing a system for viewing bone and joint radiographs (5.33), distinguishing normal structures from abnormal in chest and abdominal radiographs (5.33) and identifying gross bone or joint abnormalities in skeletal radiographs (5.22). Correlative analysis between speciality groups showed surgical and medical specialities were significantly different in their responses of two learning outcomes: basic knowledge about the contrast media benefits and risks (P= 0.01) and ability to select the most appropriate and the most cost‐effective methods of radiological investigations for clinical situations (P= 0.03). Acute specialities were not significantly different from the other two groups for these two learning outcomes. There was no statistically significant difference for other learning outcomes between the three speciality groups.  相似文献   
994.
Shortages in healthcare workers are projected to continue for the next few years. This article presents a "how- to" for organizations to attract applicants and develop an in-house training program for Certified Nurse Assistants (CNAs). The process Saint Anthony's Health Center had in executing an in-house certification program and the positive outcome experienced are presented.  相似文献   
995.
996.

Background  

Cost-effectiveness acceptability curves (CEACs) describe the probability that a new treatment or intervention is cost-effective. The net benefit regression framework (NBRF) allows cost-effectiveness analysis to be done in a simple regression framework. The objective of the paper is to illustrate how net benefit regression can be used to construct a CEAC.  相似文献   
997.
998.
The aims of the present study was to investigate if food components, as represented by a multi-component nutritional drink for tube feeding, could affect tablet disintegration of standard tablets in vitro as well as in vivo and propose a mechanism for potential food effects on tablet disintegration. The tablet disintegration was delayed between 5 min and more than 1h in the simulated gastric fed medium compared to a simple buffer. This effect was dependent on the tablet composition. A similar delay in tablet disintegration was also found in vivo after administration of the nutritional drink to three Labradors as observed by removing the tablet from the stomach at different times through a gastric fistula. The delay in tablet disintegration appeared to be caused by precipitation of a film, mainly consisting of protein, on the tablet surface as indicated by disintegration studies with pure nutrients, identification by IR spectroscopy of contents of precipitates obtained in a model study were the nutrients were incubated with different tablet excipients and visual observations of tablets exposed to the simulated fed medium. The drug dissolution of a soluble compound, metoprolol tartrate, from a standard tablet was also strongly delayed in the simulated fed medium. In conclusion, food, could significantly delay tablet disintegration and drug dissolution in the stomach by formation of a film around the tablets. This effect could be monitored by a simple in vitro disintegration test using a test medium based on a nutritional drink. More studies are needed to investigate the significance of the slow tablet disintegrations on bioavailability and for which types of food the present effect occurs.  相似文献   
999.
In summarizing this discussion of the meaning of EvBP and best practice and their relationship to each other, there is merit in beginning with a delineation of six characteristics of quality care. These six characteristics synthesized by Brown (2001, p. 1) consist of care that is (a) patient centered, (b) scientifically based, (c) population outcomes based, (d) refined through quality improvement and benchmarking, (e) individualized to each patient, and (f) compatible with system policies and resources. These characteristics set the stage and reinforce critical aspects of the definition of both concepts: EvBP and best practice. For evidence to be meaningfully and successfully translated into practice by individuals, and groups of practitioners, the concept of best practice adds an organizational and ongoing quality monitoring to promote continual improvement. Best practice is not a specific practice per se but rather a level of agreement about research-based knowledge and an integrative process of embedding this knowledge into the organization and delivery of health care. The question "Are EvBP and best practice the same?" has guided this discussion, which has focused on how these concepts are related to each other but not the same. Best practice requires a level of agreement about evidence to be integrated into practice. The challenge now is to answer this question: "How can practice be built based on evidence and an environment supportive of this kind of practice?" The struggle needing to be faced is how to devise strategies to operationalize best practice. A beginning identification of the multiple questions and issues in doing so are outlined by Harrison, Logan, Lynn, and Graham (1998), and Newman and Papadopoulos (2000). Plus, Mulhall (1998) poses the challenging question of how is nursing best placed to maximize the benefits that some kind of evidenced-based care can bring? Research is needed into the situations under which evidence can be adopted into practice--and into the consequences of doing so. Best practice, built on a foundation of EvBP, can bridge the practice-research gap and provide a basis for researchers and clinicians to work together to translate research into meaningful practice. Understanding the concept of EvBP and joining together to devise best practice for health care organizations can promote achieving the goal of desired patient outcomes.  相似文献   
1000.
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