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Levin  DN; Hu  XP; Tan  KK; Galhotra  S 《Radiology》1989,171(1):277-280
Image processing and volume rendering have been applied to magnetic resonance (MR) images to produce three-dimensional views of the surface of the brain. Four healthy volunteers and 17 patients with a variety of disorders underwent MR imaging of the head, and these images were processed and subjected to volume rendering. The resulting three-dimensional views depict abnormalities of the brain surface, as well as important landmarks of normal brain surface anatomy such as precentral, postcentral, superior temporal, and inferior frontal gyri, which are difficult to identify on cross-sectional images.  相似文献   
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Currently, there is a need for therapeutic vaccines that are effective in inducing robust T helper type 1 (Th1) immune responses capable of mediating viral clearance in chronic hepatitis B infection. Hepatitis B therapeutic vaccines were designed and formulated by loading the hepatitis B core antigen (HBcAg) into poly(D,L-lactic-acid-co-glycolic acid) (PLGA) nanoparticles with or without monophospholipid A (MPLA), a Th1-favoring immunomodulator. These particles were around 300 nm in diameter, spherical in shape and had approximately 50% HBcAg encapsulation efficiency. A single immunization with a vaccine formulation containing (MPLA+HBcAg) coformulated in PLGA nanoparticles induced a stronger Th1 cellular immune response with a predominant interferon-gamma (IFN-gamma) profile than those induced by HBcAg alone, free (HBcAg+MPLA) simple mixture or HBcAg-loaded nanoparticles in a murine model. More importantly, the level of HBcAg-specific IFN-gamma production could be increased further significantly by a booster immunization with the (HBcAg+MPLA)-loaded nanoparticles. In summary, these results demonstrated that codelivery of HBcAg and MPLA in PLGA nanoparticles promoted HBcAg-specific Th1 immune responses with IFN-gamma production. These findings suggest that appropriate design of the vaccine formulation and careful planning of the immunization schedule are important in the successful development of effective HBV therapeutic vaccines.  相似文献   
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Background: One of the most important limitations of standard pulse oximeters is the inability to detect changes in respiratory rate until oxygenation is affected. This study sought to determine if analysis of the plethysmogram by wavelet transforms would enable the determination of changes in respiratory rate at an earlier stage.

Methods: Ten healthy adult volunteers were monitored, breathing at baseline and predetermined respiratory rates, using a standard pulse oximeter. Photo-plethysmograms captured in an attached lap top computer were then analysed using wavelet transforms.

Results: Determination of baseline respiratory rate and subsequent changes including apnoea were easily identified.

Comment: Wavelet transforms permit the accurate determination of respiratory rate by a standard pulse oximeter.

  相似文献   
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The development of instruments to measure clinical competence in nursing shows little evidence of a systematic approach and studies of reliability and validity are absent. The present study was carried out using data on practice assessment collected in the course of a post-registration nursing programme. The data were analysed for internal consistency and intra-rater reliability. The instrument used to assess practice in the present study is highly internally consistent and there is evidence to support intra-rater reliability. However, further development and testing of the instrument is required.  相似文献   
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Quality assurance in British National Health Service provision stresses the importance of taking account of the consumer's viewpoint Elderly patients with dementia are not always able to contribute usefully to satisfaction surveys Therefore, their carers' views were sought in order to assess the quality of services offered to this client group Forty-one carers of patients discharged from the eight wards for the elderly mentally ill in Leicestershire, England, were randomly selected Individual focused interviews were conducted in carers' own homes Both quantitative and qualitative data were obtained by use of a questionnaire designed to tap the patients'/carers' experiences from preadmission, through hospital stay to post-discharge Interviewees were asked to describe their favourable/unfavourable impressions of, and reactions to, all aspects of hospital care These interviews were tape-recorded Analysis of the data included quantitative measurements of scale ratings Grounded theory was used to analyse qualitative data A wealth of information was uncovered using this research technique Much that was positive about the service was elicited However, carers highlighted areas where they felt the quality of care could be improved within all the foci discussed Twenty-two recommendations for quality improvements in service provision were made in the report as a result of this survey  相似文献   
89.
An inhibitor of adrenal steroid biosynthesis, aminoglutethimide, was administered to seven patients with low renin essential hypertension, and the antihypertensive action of the drug was compared with its effects on adrenal steroid production. In all patients aldosterone concentrations in plasma and urine were within normal limits before the study. Mean arterial pressure was reduced from a pretreatment value of 117+/-2 (mean+/-SE) mm Hg to 108+/-3 mm Hg after 4 days of aminoglutethimide therapy and further to 99+/-3 mm Hg when drug administration was stopped (usually 21 days). Body weight was also reduced from 81.6+/-7.2 kg in the control period to 80.6+/-7.0 kg after 4 days of drug treatment and to 80.1+/-6.7 kg at the termination of therapy. Plasma renin activity was not significantly increased after 4 days of treatment but had risen to the normal range by the termination of aminoglutethimide therapy. Mean plasma concentrations of deoxycorticosterone and cortisol were unchanged during aminoglutethimide treatment whereas those of 18-hydroxydeoxycorticosterone, progesterone, 17alpha-hydroxyprogesterone, and 11-deoxycortisol were increased as compared to pretreatment values. In contrast, aminoglutethimide treatment reduced mean plasma aldosterone concentrations to about 30% of control values. Excretion rates of 16beta-hydroxydehydroepiandrosterone, 16-oxo-androstenediol, 17-hydroxycorticosteroids and 17-ketosteroids, and the secretion rate of 16beta-hydroxydehydroepiandrosterone were not significantly altered by aminoglutethimide treatment whereas the excretion rate of aldosterone was reduced from 3.62+/-0.5 (mean+/-SE) in the control period to 0.9+/-0.2 mug/24 h after 4 days and to 1.1+/-0.3 mug/24 h at the termination of aminoglutethimide treatment.The gradual lowering of blood pressure and body weight during aminoglutethimide therapy is consistent with the view that the antihypertensive effect of the drug is mediated through a reduction in the patients' extracellular fluid volume, probably secondary to the persistent decrease in aldosterone production. The observation that chronic administration of aminoglutethimide lowered blood pressure in these patients and elevated their plasma renin activity to the normal range without decreasing production of the adrenal steroids, deoxycorticosterone, 18-hydroxydeoxycorticosterone, and 16beta-hydroxydehydroepiandrosterone, makes it unlikely that these steroids are responsible either for the decreased renin or the elevated blood pressure in patients with low renin essential hypertension.  相似文献   
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This cross-sectional study compared quality of life and side effects in 108 users of olanzapine or risperidone suffering schizophrenia and being attended at psychiatric ambulatory services in Rio Grande do Norte, Brazil. Economic, socio-demographic, anthropometric, biochemical, and hormonal variables were compared. The EuroQoL Five-Dimension Scale (EQ-5D) was used to evaluate quality of life, and side effects were assessed using the Udvalg for Kliniske Undersøgelser (UKU) Side Effect Rating Scale and the Simpson–Angus Scale. Data were analysed using the χ2 test and Student’s t test, with a significance level of 5 %.The household incomes of approximately 80 % of patients were <2.0 minimum wages ($678). Anthropometric variables (waist circumference, hip circumference, weight, waist-to-hip ratio) and systolic and diastolic blood pressure were noted among male olanzapine users (all p < 0.05). EQ-5D scores showed that olanzapine use significantly impacted self-help ability (p < 0.001). Risperidone users had a mean quality-adjusted life year value of 1. Mean total Simpson–Angus Scale scores was 0.38 for olanzapine users and 0.11 for risperidone users (p < 0.02). Significant differences in UKU were observed for the following items: asthenia/lassitude/fatigue (higher among olanzapine users, p = 0.02), dystonia (higher among olanzapine users, p = 0.01), tremors (higher among olanzapine users, p = 0.03), gynecomastia (higher among risperidone users, p < 0.02), and ejaculatory dysfunction (higher among risperidone users, p < 0.02). Olanzapine users had impaired quality of life, which can be explained in part by adverse motor, biochemical, and hormonal effects characteristic of metabolic syndrome.  相似文献   
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