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BACKGROUND: Early in the HIV epidemic, hospitals developed strict isolation policies for patients with HIV infection, some of which have not been revised. The objectives of this study were to examine patient attitudes about rooming with persons with various medical conditions, including HIV, and to assess their knowledge about the transmission of HIV. METHODS: One hundred four inpatients at a university hospital were surveyed by means of a structured interviewer-administered questionnaire. Patients were asked about preference for a single or double room, and about their objections to rooming with patients with HIV infection and other medical conditions. The questionnaire also examined subject's knowledge about the transmission of HIV. RESULTS: Of 104 inpatients surveyed, 55% objected to rooming with an HIV-seropositive patient. Patients who objected to rooming with an HIV-seropositive patient were also more likely to object to rooming with a disfigured patient (relative risk = 1.5; 95% CI, 1.1 to 2.2), or with a demented patient (relative risk = 1.7; 95% CI, 1.0 to 2.9). Also, patients who objected to rooming with an HIV-seropositive patient had greater misconceptions about the transmissibility of HIV infection. CONCLUSIONS: A significant proportion of patients reported an unwillingness to room with patients with HIV infection, but also had misconceptions about the transmissibility of HIV. Current rooming policies may perpetuate misconceptions about the possibility of causal transmission of HIV.  相似文献   
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This study evaluated the effects of stimulus repetition rate, phase, and frequency on the auditory brainstem response (ABR) in normal-hearing neonates and adults. In both neonates and adults, the results clearly showed large ABR wave V latency differences between condensation and rarefaction for low-frequency stimuli. Phase dependent latency effects are believed to be a result of the phase-sensitive low-frequency neurons. Increasing stimulus repetition rate produced greater wave V latency shift in neonates than in adults. The consequences of rate changes were independent of stimulus phase and frequency.  相似文献   
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A mutant derivative of Klenow fragment DNA polymerase containing serine substituted for tyrosine at residue 766 has been shown by kinetic analysis to have an increased misinsertion rate relative to wild-type Klenow fragment, but a decreased rate of extension from the resulting mispairs (Carroll, S. S., Cowart, M., and Benkovic, S. J. (1991) Biochemistry 30, 804-813). In the present study we use an M13mp2-based fidelity assay to study the error specificity of this mutator polymerase. Despite its compromised ability to extend mispairs, the Y766S polymerase and a Y766A mutant both have elevated base substitution error rates. The magnitude of the mutator effect is mispair-specific, from no effect for some mispairs to rates elevated by 60-fold for misincorporation of TMP opposite template G. The results with the Y766S mutant are remarkably consistent with the earlier kinetic analysis of misinsertion, demonstrating that either approach can be used to identify and characterize mutator polymerases. Both the Y766S and Y766A mutant polymerases are also frameshift mutators, having elevated rates for two-base deletions and a 276-base deletion between a direct repeat sequence. However, neither mutant polymerase has an increased error rate for single-base frameshifts in repetitive sequences. This error specificity suggests that the deletions generated by the mutator polymerases are initiated by misinsertion rather than by strand slippage. When considered with recent structure-function studies of other polymerases, the data indicate that the nucleotide misinsertion and strand-slippage mechanisms for polymerization infidelity are differentially affected by changes in distinct structural elements of DNA polymerases that share similar subdomain structures.  相似文献   
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This study established the emergence of stable individual differences in neurobehavioral functioning prior to birth and examined their relation to subsequent infant temperament. Fetal heart rate and movement were recorded longitudinally for 31 fetuses at 6 gestational ages beginning at 20 weeks' gestation. Maternally reported temperament data were collected at 3 and 6 months. Moderate stability in all measures except reactivity was apparent at some time before birth. By 36 weeks, fetal neurobehavior accounted for between 22% and 60% of the variance in prediction of temperament scores. In general, more active fetuses were more difficult, unpredictable, unadaptable, and active infants. Higher fetal heart rate was associated with lower emotional tone, activity level, and predictability. We conclude that features of fetal neurobehavior provide the basis for individual differences in reactivity and regulation in infancy.  相似文献   
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Increasing emphasis is now being placed on the assessment of patient outcomes, both in evaluating medical interventions and in quality assurance initiatives. Clinicians, purchasers, managers and researchers need outcome measures that are valid, reliable and responsive. This paper describes the theory and practice underlying the development of outcome measures for two chronic conditions, asthma and diabetes, for application in ambulatory settings. Existing generic and condition-specific health status and health-related quality-of-life measures were administered to almost 1300 patients. The psychometric properties of these measures were examined to identify those that were of adequate validity and reliability in these population groups. Step-wise regression procedures were then used to identify a core set of scales that best predicted patients' general health perceptions, which could be used in measuring general health outcomes for each of these groups. These core sets consist of up to 40 items, spanning physical function, energy and vitality, emotional well-being and condition-specific aspects of health such as symptom control. Further analysis is being carried out to assess the responsiveness to change of these core item sets.  相似文献   
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We describe the radiological findings at presentation and follow up in 24 adult patients with Burkitt's and Burkitt-like lymphoma, age range 17-67 years. This is an older age group than previously described in North American series, but the clinical and imaging characteristics appear similar. Disease confined to the abdomen was seen in 12 (50%) at presentation, of whom 11 had bowel or mesenteric tumours. Of those with bowel involvement, five patients had disease that had arisen in the ileocaecal region. Intra-abdominal disease was large volume (greater than 5 cm) in the majority of patients. Four patients (17%) had small isolated masses in the head and neck region, two (8%) had isolated unilateral axillary lymphadenopathy. Six (25%) patients presented with disseminated disease, all with hepatic and/or splenic involvement, intra-abdominal and peripheral lymphadenopathy. Three of these patients with disseminated disease were human immunodeficiency virus (HIV) positive. Neurological symptoms were present in a total of five patients at presentation or relapse but positive imaging findings were present in only two patients who had MRI. Computed tomography (CT) head scans performed in four patients were normal. Disease recurrence most commonly occurred within the abdomen.  相似文献   
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