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41.
AIMS: To investigate the clinical value and practice of reflective testing, a new term to describe the practice of adding on tests when reporting or clinically authorising results. METHODS: A consultant medical biochemist collected over a calendar year (2001) copies of clinical biochemistry reports on samples to which he had added on either iron studies (iron, total iron binding capacity (TIBC), and percentage saturation), or vitamin D. Iron studies and vitamin D were added on when biochemical results, available clinical information, demographic data, and clinical experience-or combinations thereof-suggested the possibility of haemochromatosis or vitamin D deficiency, respectively. The number of reports that the consultant authorised was estimated for the same calendar year. The number and percentage of raised TIBC percentage saturation and low vitamin D results from the tests that were added on were collated. RESULTS: Raised TIBC saturation values were found in 28 patients (18.7% of the iron studies added on), of whom 16 were subsequently genotyped, eight having a genotype consistent with haemochromatosis. Thirty one patients with vitamin D deficiency (23.1% of the vitamin D tests added on) were identified. CONCLUSIONS: The addition of iron studies and vitamin D tests by a laboratory clinician, when reporting, resulted in the identification of patients with haemochromatosis and vitamin D deficiency. The practice of adding on tests should be called reflective testing, because it is discretionary and is based on the clinical judgement of a laboratory clinician in the interpretation of results.  相似文献   
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L1 is a neural cell adhesion molecule mainly involved in axon guidance and neuronal migration during brain development. Mutations in the human L1 gene give rise to a complex clinical picture, with mental retardation, neurologic abnormalities and a variable degree of hydrocephalus. Recently, a transgenic mouse model with a targeted null mutation in the L1 gene was generated. These knockout (KO) mice show hypoplasia of the corticospinal tract. Here we have performed further studies of these KO mice including magnetic resonance imaging of the brain, neuropathological analysis and behavioral testing. The ventricular system was shown to be abnormal with dilatation of the lateral ventricles and the 4th ventricle, and an altered shape of the Sylvius aqueduct. Additionally, the cerebellar vermis of the KO mice is hypoplastic. Their exploratory behavior is characterized by stereotype peripheral circling reminiscent of that of rodents with induced cerebellar lesions.   相似文献   
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The construct of transformation has been presented in many research studies as the epitome of living with a chronic illness. Because it has been inadequately defined, however, many other concepts (e.g., hope, meaning, control) are used in ways that suggest considerable overlap and correspondence with transformation. This article represents an attempt to explicate the structures and processes of transformation as they were revealed in a qualitative inquiry into the experience of individuals with Type I diabetes. In the accounts constructed with participants in this study, the process of personal transformation was significant in the attainment of healthy outcomes. The authors describe this transformation and examine its relationship to control and to the valued outcomes of intensified sense of self, meaning, and mastery.  相似文献   
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Although there is an abundance of literature about how to conduct qualitative research and some consideration of possible threats to researchers' psychological well-being, there is little mention of the personal safety issues that researchers face while in the field. Few researchers have attempted to address the issue of researcher safety as a methodological concern. Consequently, there are minimal guidelines available to researchers to prevent and avoid dangerous incidents in the course of their research. The following is a discussion of the general guidelines for developing a protocol to address the issue of researcher safety in the field. These guidelines have been extrapolated from safety guidelines and policies written for students and clinicians who enter a client's home in their role as health care practitioners, relevant literature in the area of safety for researchers in violent settings, resources such as safety guidelines for employees, and the personal experiences of several researchers.  相似文献   
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Mini-thoracotomy for diaphragmatic plication with thoracoscopic assistance   总被引:1,自引:0,他引:1  
We describe a technique of mini-thoracotomy to plicate the paralyzed hemidiaphragm with thoracoscopic assistance. Most of the hemidiaphragm can be plicated expeditiously under direct vision with light derived from a posterior thoracoscope placed in the auscultatory triangle. Videoscopic vision is employed only occasionally when the view of the posteromedial hemidiaphragm is obscured. Continuous suture traction can be easily applied through the mini-thoracotomy, thus maintaining suture tension and enabling maximal inversion of the elevated hemidiaphragm.  相似文献   
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Heart rate (HR) recovery from heavy exercise is associated with a shift in cardiac sympatho-vagal balance and a transient hypokalaemia. Since changes in extracellular potassium ([K+]0) affect membrane currents in the sino-atrial node, in particular the acetylcholine-activated potassium current (I(K,ACh)), the hyperpolarization-activated current (I(f)) and the L-type calcium current (I(Ca,L)), we investigated whether mimicking [K+]0 concentrations seen during and immediately after exercise could directly modulate the HR response to vagal nerve stimulation (VNS) in the isolated guinea-pig atria preparation pre-stimulated with noradrenaline (NA, 1 microM). Lowering [K+]0 from 4 to 3 mM significantly enhanced the HR response to VNS (5 Hz, 5 V, 30 s, deltaHR 84.5 +/- 14.1 bpm and 119.3 +/- 18.2 bpm, respectively). Increasing [K+]0 to 8 or 10 mM significantly decreased the drop in HR with VNS in comparison to the response to 3 mM K+ Tyrode (deltaHR 56.4 +/- 9.1 bpm and 52.1 +/- 8.7 bpm, respectively). These results could be simulated using the OXSOFT heart sino-atrial node computer model by activating I(K,ACh) during changes in [K+]0. However, changing [K+]0 in the model had no significant effect on the decrease in beating frequency brought about by decreasing I(f) or I(Ca,L). We conclude that the magnitude of the decrease in HR with VNS is enhanced in low [K +]0 and reduced in high [K+]0. The increased efficacy of cardiac vagal activation in low [K+]0 might therefore facilitate the drop in HR after heavy exercise where there is a transient hypokalaemia. Modelling suggests this result may be explained by the effects of changes in [K+]0 on the current-voltage relationship for I(K,ACh).  相似文献   
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