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61.
Estes  DN; Magill  HL; Thompson  EI; Hayes  FA 《Radiology》1990,177(2):449-453
While avid accumulation of gallium-67 citrate and technetium-99m methylene diphosphonate (MDP) occurs initially in most cases of primary Ewing sarcoma, uptake after therapy is less well defined. Thirty patients with Ewing sarcoma who underwent Ga-67 and bone scintigraphy at diagnosis, at completion of therapy, and at relapse from 1978 to 1988 were evaluated. All 30 patients showed less primary site Ga-67 activity following therapy. Twenty-three of 28 patients who underwent corresponding bone scintigraphy showed less uptake, but residual activity was usually more intense than with Ga-67. Avid reaccumulation of Ga-67 occurred in four of five patients with primary site relapse, while patients who underwent bone scintigraphy showed less change. It was concluded that a greater decrease in Ga-67 than in Tc-99m MDP uptake often occurs in patients successfully treated for primary Ewing sarcoma. Information obtained at Ga-67 scintigraphy is most likely to be helpful if results of bone scintigraphy remain abnormal or if occult relapse is suspected.  相似文献   
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This paper reports on the findings of a study conducted into the perceptions of final year Project 2000 pre-registration students towards their pre-registration education programme The aim of the research was to discover how students perceive their training in terms of value, relevance, intellectual potency, teaching methods and organization Data were collected using the Hoste scale which has been developed for the evaluation of educational courses A convenience sample of students (n = 131) within one college of nursing were invited to participate Findings include a particularly high level of satisfaction with Project 2000 in terms of value, breadth and relevance Organization and liveliness of the course were perceived much less satisfactorily There was a trend for a statistically significant difference between the mean scores of the theoretical and practical components of the course The findings are discussed with particular reference to the perceptions of theory and practice within the educational programme  相似文献   
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Ideally biosignatures can be detected at the early infection phase and used both for developing diagnostic patterns and for prognostic triage. Such biosignatures are important for vaccine validation and to provide risk stratification to a population such as for the identification of individuals who are exposed to biological or chemical agents and who are at high risk for developing an infection. The research goal is to detect broad based biosignature models and is initially focused on developing effective computer-augmented pathology tied to animal models developed at the University of New Mexico (UNM). Using lung tissue from infected and nai ve mice, feature extraction from images of the tissue under a specialized microscope, and Bayesian networks to analyze the data sets of features, we were able to differentiate normal from diseased samples and viral from bacterial samples in mid to late stages of infection. This effort has shown the potential effectiveness of computer-augmented pathology in this application. The extended research intends to couple analysis of serum, microarray analysis of organs, proteomic data and the pathology. The rational for the current invasive procedure on animal models is to facilitate the development of data analysis and machine learning techniques that can eventually be generalized to the task of discovering non-invasive and early stage biosignatures for human models.  相似文献   
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The findings from a Florence Nightingale Scholarship to the USA and Canada, investigating the educational preparation of advanced practice nurses, are reported. The author considers a number of issues facing curriculum designers who might wish to develop clinically based advanced practice nurse programmes in the UK. Utilizing the experiential nature of personal visits, along with the available literature, the strategy adopted by some American and Canadian universities is highlighted to exemplify curriculum issues likely to be encountered in the UK. A definition of advanced nursing practice is provided as a foundation for discussion on curricular construction. This is followed by a discussion on advanced role nomenclature and components and characteristics of the 'nurse practitioner', 'clinical nurse specialist', 'nurse consultant' and 'nurse clinician', in order to clarify terminology and disentangle different advanced practice roles. The issues examined include the academic level of advanced practice nurse programmes; the determination of curricular content based on both a 'generalist' and 'specialist' model of practice; factors considered when exploring advanced practice competencies; and the resource implications for delivering opposing curriculum models. The paper suggests that there is a unique opportunity for advanced practice nursing to establish a key collaborative relationship in the delivery of health care, based on a nursing model, graduate study and the integration of key nursing and related concepts into clinical practice.  相似文献   
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99mTc-Pertechnetate (99mTcO4-) has widespread clinical use in the diagnosis and evaluation of dysfunctions in many different tissues. However, despite the broad clinical application of this radionuclide, very little is known about the mechanism by which 99mTcO4- enters a cell. We report evidence here that 99mTcO4- shares the Na+/K+/Cl- co-transport system localized to the basolateral membrane of rat parotid acinar cells. 99mTcO4- uptake by these cells was quite rapid (t1/2 approximately 30 s), was completely inhibited by the loop diuretics furosemide and bumetanide, and was markedly dependent on the presence of Na+, K+, and Cl- in the extracellular medium. Relative to uptake measured in the presence of physiological extracellular salt concentrations (Hanks' salts), 99mTcO4- uptake was inhibited 80% by sodium replacement and 50% by potassium replacement. When Cl- was replaced with the physiologically inert anion gluconate a threefold stimulation in 99mTcO4- uptake resulted. These observations provide strong evidence that 99mTcO4- can substitute for Cl- as a substrate for the Na+/K+/Cl- co-transporter and indicate that 99mTcO4- uptake by salivary glands (e.g., as seen with salivary scintiscans), and possibly by a variety of other tissues, reflects the functional activity of this co-transport mechanism.  相似文献   
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Background

The aim was to examine the numbers of hours worked and patient visits provided by age and gender of dentists in Australia, and compare with previous estimates to describe trends.

Methods

Data were collected from a random sample (N = 2961) of Australian dentists. Private sector dentists working in clinical practise were included in the analysis.

Results

The response rate was 49% (N = 1345 dentists). Hours per year worked and number of patient visits per year were lower for dentists aged 65 years and older compared with younger dentists, and were higher for male compared with female dentists aged 35–45 to 55–64 years. Hours per year worked were lower in 2013–2014 than reported in 2009–2010, but the number of patient visits in 2013–2014 was similar to the previously reported estimate from 2009–2010.

Conclusions

Hours worked and visits provided were only lower among older dentists aged 65 years or more. Male dentists tend to work more hours per year and provide more patient visits per year than female dentists. Over the last decade, Australian dentists maintained a stable output of visits per year despite a trend towards fewer hours worked per year.  相似文献   
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