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Knowledge of the statistical properties of reconstructed single photon emission computed tomography (SPECT) and positron emission tomography (PET) images would be helpful for optimizing acquisition and image processing protocols. We describe a non-parametric bootstrap approach to accurately estimate the statistical properties of SPECT or PET images whatever the noise properties in the projections and the reconstruction algorithm. Using analytical simulations and real PET data, this method is shown to accurately predict the statistical properties, including the variance and covariance, of reconstructed pixel values for both linear (filtered backprojection) and non-linear (ordered subset expectation maximization) reconstruction algorithms.  相似文献   
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Background:  

Rating scales like the visual analogue scale, VAS, and the verbal rating scale, VRS, are often used for pain assessments both in clinical work and in research, despite the lack of a gold standard. Interchangeability of recorded pain intensity captured in the two scales has been discussed earlier, but not in conjunction with taking the influence of pain etiology into consideration.  相似文献   
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Samenvatting Een systeem voor dunnelaagchromatografie wordt beschreven met behulp waarvan twaalf verschillende benzodiazepinen kunnen worden geïdentificeerd en waarmee tevens eventuele ontledingsprodukten kunnen worden aangetoond. Er wordt gebruik gemaakt vanhptlc Silica Gel 60 F254 plaatjes en als loopvloeistof wordt tolueen-methanol (96 + 6) gebruikt.De vlekjes kunnen direct onderuv-licht worden waargenomen; ze kunnen nader worden geïdentificeerd na bespuiten met zwavelzuur en/of het reagens van Bratton Marshall. Van enkele benzodiazepinen kan de identiteit echter pas worden vastgesteld nadat ze zijn gehydrolyseerd.  相似文献   
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OBJECTIVE: The aim of this study was to describe the number of erupted teeth, sucking habits, tongue morphology, facial expression and speech in children with Down syndrome (DS) aged 48 +/- 6 months and treated from 6 months of age with palatal plates in combination with speech and language therapy. METHODS: The research took the form of a multicentre, multidisciplinary, longitudinal study of children with DS followed from the age of 6 months. A total of 37 children with DS were included. One child could not cooperate at all and was excluded from the evaluations. In combination with speech and language intervention provided by speech and language therapists, the children used palatal plates provided by dentists from 6 months of age. In the evaluation, the children in the sample (n = 36) were compared with two similarly aged control groups: one group of children with DS who never had used palatal plates (n = 31) and one group of children with normal development (n = 36). The evaluation of oral parameters was performed by dentists after calibration. Registration of facial expression and speech was done by a speech and language therapist, and the evaluation was done by two speech and language therapists and one phonetician who were calibrated in joint discussions. RESULTS: In contrast to the children with DS in the control group, the subjects in the study were found to have as many erupted teeth as the children with normal development. The prevalence of sucking habits did not differ between the three groups. Only children with DS sucked their tongue, a toy or other things in addition to a thumb or dummy. The prevalence of tongue diastase in the study group with DS was of the same magnitude as in the evaluation at the age of 18 +/- 3 months. The palatal plates were used by 57-65% of the children without any larger problems. In the study sample, the possible beneficial effects of palatal plate therapy were a lower prevalence of posterior cross-bite, a higher prevalence of frontal cusp-to-cusp relation and a lower prevalence of frontal open bite. Evaluation of facial expression and speech showed a higher score for facial expression and a better communicative capacity in the children in the study group than in the control children with DS. CONCLUSIONS: In children with DS, palatal plate therapy between 6 and 48 months of age in connection with speech and language intervention had a positive effect on occlusion, oral motor function, facial expression and speech. No harmful effects were observed. Although this is a valuable method, however, it must be emphasized that palatal plate therapy puts additional demands on already burdened children and their caretakers.  相似文献   
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This article focuses on Swedish nurse leaders and is aimed at achieving a more complete and differentiated understanding of what constitutes caring in the perioperative culture as well as their knowledge and responsibility for the development of caring. Interviews with open-ended questions were conducted with 10 nurse leaders, in which they described their experiences of developing perioperative caring. The interpretation process was based on Gadamer's philosophy of hermeneutics. The findings indicate that developing a perioperative caring culture is a struggle to retain sight of the patient, a process that includes the following 6 phases: (1) when the nurse leaders understood perioperative caring as a process, the nurse's and patient's shared world became obvious to them; (2) safeguarding the patient's position as a unique human being; (3) safeguarding the nurse's welfare by creating a compassionate atmosphere; (4) promoting an idea means never giving up; (5) attaching importance to being trustworthy; and (6) being involved in a dynamic interaction, comprising communion and reciprocity. The most important goal of nursing leadership is to safeguard the welfare of the suffering patient and the relationship between the nurse leader and nursing staff, based on the motive of caritas derived from the idea of humanistic caring.  相似文献   
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