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81.
Miller A Hall CS Buchanan RW Buckley PF Chiles JA Conley RR Crismon ML Ereshefsky L Essock SM Finnerty M Marder SR Miller DD McEvoy JP Rush AJ Saeed SA Schooler NR Shon SP Stroup S Tarin-Godoy B 《The Journal of clinical psychiatry》2004,65(4):500-508
BACKGROUND: The Texas Medication Algorithm Project (TMAP) has been a public-academic collaboration in which guidelines for medication treatment of schizophrenia, bipolar disorder, and major depressive disorder were used in selected public outpatient clinics in Texas. Subsequently, these algorithms were implemented throughout Texas and are being used in other states. Guidelines require updating when significant new evidence emerges; the antipsychotic algorithm for schizophrenia was last updated in 1999. This article reports the recommendations developed in 2002 and 2003 by a group of experts, clinicians, and administrators. METHOD: A conference in January 2002 began the update process. Before the conference, experts in the pharmacologic treatment of schizophrenia, clinicians, and administrators reviewed literature topics and prepared presentations. Topics included ziprasidone's inclusion in the algorithm, the number of antipsychotics tried before clozapine, and the role of first generation antipsychotics. Data were rated according to Agency for Healthcare Research and Quality criteria. After discussing the presentations, conference attendees arrived at consensus recommendations. Consideration of aripiprazole's inclusion was subsequently handled by electronic communications. RESULTS: The antipsychotic algorithm for schizophrenia was updated to include ziprasidone and aripiprazole among the first-line agents. Relative to the prior algorithm, the number of stages before clozapine was reduced. First generation antipsychotics were included but not as first-line choices. For patients refusing or not responding to clozapine and clozapine augmentation, preference was given to trying monotherapy with another antipsychotic before resorting to antipsychotic combinations. CONCLUSION: Consensus on algorithm revisions was achieved, but only further well-controlled research will answer many key questions about sequence and type of medication treatments of schizophrenia. 相似文献
82.
BACKGROUND: Critical realism is a relatively new philosophical perspective that combines a realist ontology with a relativist epistemology in subscribing to a form of "robust" relativism. The potential benefits of adopting a critical realist approach are considered in two areas of evaluation research: theory-driven programme evaluation and policy evaluation. AIM: The aim of the paper is to identify the main features of critical realism and explore its potential as a philosophical framework in the field of evaluation research. CONCLUSION: We argue that critical realism provides a coherent framework for evaluation research that is based on the understanding of causal mechanisms. This is particularly important for frontline services seeking to use evidence-based interventions, as interventions need to be properly understood if they are to be used effectively in the context of clinical practice. Critical realism can also add depth to policy analysis. However, there is a potential for critical realists to drift beyond the boundary that separates scientific knowledge from speculative theory when making recommendations about the best course of action to follow. 相似文献
83.
84.
The impact of moderate sleep loss on neurophysiologic signals during working-memory task performance 总被引:3,自引:0,他引:3
STUDY OBJECTIVES: This study examined how sleep loss affects neurophysiologic signals related to attention and working memory. DESIGN: Subjective sleepiness, resting-state electroencephalogram, and behavior and electroencephalogram during performance of working-memory tasks were recorded in a within-subject, repeated-measures design. SETTING: Data collection occurred in a computerized laboratory setting. Participants: Sixteen healthy adults (mean age, 26 years; 8 female) Interventions: Data from alert daytime baseline tests were compared with data from tests during a late-night, extended-wakefulness session that spanned up to 21 hours of sleep deprivation. MEASUREMENTS AND RESULTS: Alertness measured both subjectively and electrophysiologically decreased monotonically with increasing sleep deprivation. A lack of alertness-related changes in electroencephalographic measures of the overall mental effort exerted during task execution indicated that participants attempted to maintain high levels of performance throughout the late-night tests. Despite such continued effort, responses became slower, more variable, and more error prone within 1 hour after participants' normal time of sleep onset. This behavior failure was accompanied by significant degradation of event-related brain potentials related to the transient focusing of attention. CONCLUSIONS: Moderate sleep loss compromises the function of neural circuits critical to subsecond attention allocation during working-memory tasks, even when an effort is made to maintain wakefulness and performance. Multivariate analyses indicate that combinations of working-memory-related behavior and neurophysiologic measures can be sensitive enough to permit reliable detection of such effects of sleep loss in individuals. Similar methods might prove useful for assessment of functional alertness in patients with sleep disorders. 相似文献
85.
Noninvasive cardiovascular markers of acoustically induced arousal from non-rapid-eye-movement sleep
STUDY OBJECTIVES: Changes in cardiovascular measures such as heart rate (HR) and pulse transit time (PTT) have been advocated as sensitive markers of autonomic arousal from sleep. In animal studies, alerting stimuli produce particularly marked skin vascular responses. We hypothesized that changes in skin vascular conductance would provide more sensitive markers of autonomic arousal during sleep compared to central cardiovascular response measures such as HR and PTT. DESIGN: Cardiovascular responses to auditory-induced arousals were recorded during overnight sleep studies. SETTING: Sleep disorders unit in a 270-bed teaching hospital. PARTICIPANTS: Eleven young healthy male subjects. INTERVENTIONS: Throughout ovemight sleep studies, auditory tones (5-second duration, 54-90 decibels, 22-56 per subject) were presented during non-rapid-eye-movement sleep. Beat-by-beat HR, PTT, laser-Doppler fingertip skin blood flow (SBF) and finger and ear photoplethysmogram pulse wave amplitudes (PWA) were measured in the 20 seconds preceding and 30 seconds following each tone and compared to control measurements obtained during 50-second periods of recording with no stimulus (no tone, 6-22 per subject). Electroencephalographic (EEG) arousals were scored according to standard criteria (American Sleep Disorders Association) into no discemible, 3- to 10-second duration, or 10- to 15-second duration arousals. Poststimulus cardiovascular measurements were expressed as a percentage of the prestimulus mean and response magnitudes quantified from peak responses and the area under the poststimulus response curve. The ability of each cardiovascular response measure to discriminate EEG arousals (EEG changes lasting more than 3 seconds) was assessed from the area under the receiver operating characteristic (ROC) curve. MEASUREMENTS AND RESULTS: There were no significant changes in any cardiovascular parameter during control recordings. In contrast to all other parameters, finger PWA and SBF decreased following tones that produced no discernible EEG arousal (P < 0.05). A significant HR rise and decreases in all cardiovascular measures occurred with greater than 3-second arousals, with longer duration arousals generally exhibiting larger responses. Conventional EEG arousals (greater than 3 seconds) were relatively poorly detected from HR responses (ROC area HR rise 0.80 +/- 0.04) compared to changes in SBF (0.85 +/- 0.02), PTT (0.85 +/- 0.03) and finger PWA (0.90 +/- 0.01). CONCLUSIONS: Decreases in skin vascular conductance (finger PWA and SBF) provide sensitive markers of autonomic arousal during sleep. They are at least as sensitive as PTT for detecting conventionally scored EEG arousals and may be more sensitive in detecting "subcortical" arousals. 相似文献
86.
The ability of psychological treatment services to deliver effective and accessible mental healthcare, as demanded by the National Service Framework for mental health, is compromised by the traditional configuration of psychological therapy services, powerful gatekeeping by these services and the difficulties which exist in engaging primary care in mental healthcare. Although a number of service models have been suggested, most address access from the perspective of secondary care service providers. In particular, self-help, a powerful ideology and a clinically effective health technology, is given insufficient prominence in psychological therapy services. Self-help is often only considered for mild problems or as an adjunct to therapy, and it is assumed that mental health professionals with traditional therapeutic skills are needed to support self-help. Following a review of access and self-help in psychological therapies, the present authors propose criteria against which services could be designed in order to fully utilise self-help as a powerful health technology in psychological therapies. Accompanying these criteria is a research framework drawn from recent work on access and illness self-management that can be used to evaluate the performance of services attempting to improve access to psychological therapies. 相似文献
87.
NM?JomhaEmail author PC?Anoop Janet?AW?Elliott K?Bagnall LE?McGann 《BMC musculoskeletal disorders》2003,4(1):5
Background
The identification of live cells using membrane integrity dyes has become a frequently used technique, especially with articular cartilage and chondrocytes in situ where tissue slices are used to assess cell recovery as a function of location. The development of a reproducible computerised method of cell evaluation would eliminate many variables associated with manual counting and significantly reduce the amount of time required to evaluate experimental results.Methods
To validate a custom computerised counting program, intra-person and inter-person cell counts of nine human evaluators (three groups – unskilled, novice, and experienced) were compared with repeated pixel counts of the custom program on 15 digitised images (in triplicate) of chondrocytes in situ stained with fluorescent dyes.Results
Results indicated increased reproducibility with increased experience within evaluators [Intraclass Correlation Coefficient (ICC) range = 0.67 (unskilled) to 0.99 (experienced)] and between evaluators [ICC = 0.47 (unskilled), 0.85 (novice), 0.93 (experienced)]. The computer program had perfect reproducibility (ICC = 1.0). There was a significant relationship between the average of the experienced evaluators results and the custom program results (ICC = 0.77).Conclusions
This study demonstrated that increased experience in cell counting resulted in increased reproducibility both within and between human evaluators but confirmed that the computer program was the most reproducible. There was a good correlation between the intact cell recovery determined by the computer program and the experienced human evaluators. The results of this study showed that the computer counting program was a reproducible tool to evaluate intact cell recovery after use of membrane integrity dyes on chondrocytes in situ. This and the significant decrease in the time used to count the cells by the computer program advocate its use in future studies because it has significant advantages.88.
Quantification of the ultraviolet radiation (UVR) field in the human eye in vivo using novel instrumentation and the potential benefits of UVR blocking hydrogel contact lens 总被引:1,自引:0,他引:1
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Walsh JE Bergmanson JP Wallace D Saldana G Dempsey H McEvoy H Collum LM 《The British journal of ophthalmology》2001,85(9):1080-1085
BACKGROUND/AIMS: Certain degenerative eye conditions occur predominantly nasally, at the limbal region, and are associated with solar ultraviolet radiation (UVR) induced damage. The relative contribution to the in vivo ocular flux of (a) the reflection of UVR incident on the skin of the nose onto the nasal limbus, and (b) the focusing of UVR incident on the temporal side of the cornea onto the nasal limbus were examined. METHODS: A novel photodiode sensor array was used to measure the UVR field across the eye. In addition, a novel spectrometer set-up was used to measure the spectrum of radiation refracted across the cornea. The efficacy of UVR blocking hydrogel contact lenses in filtering incident UVR was assessed in vivo. RESULTS: Qualitative and quantitative data indicated an increase nasally of UVR. Photodiode readings showed a net UVR increase from the temporal to the nasal side. Transmission curves showed that most UVR incident on the limbal region is either absorbed by, or transmitted through, the ocular tissues. This radiation is filtered by UVR blocking soft contact lens. CONCLUSIONS: An increased UVR flux on the nasal side of the eye, due to reflection off the nasal skin, was identified in vivo. Any UVR passing through the cornea is either absorbed by the conjunctiva and/or transmitted through it onto the sclera where it is absorbed. UVR blocking hydrogel contact lenses can eliminate these sources of UVR. 相似文献
89.
Myths and folklore about drugs represent important aspects of user subcultures. This paper explores Ecstasy users' perceptions about drug folklore as it relates to the social relationships of drug user lifestyles. The data for the study were collected through in-depth interviews with 50 current or former Ecstasy users in Northern Ireland. The findings indicate that although some Ecstasy users perceive the folklore to be an accurate reflection of reality others report that social relations among users change with continued usage, occur within selected venues, or are influenced by greater cultural relations that characterize mainstream society. 相似文献
90.
Replacement of fish oil with rapeseed oil in diets of Atlantic salmon (Salmo salar) affects tissue lipid compositions and hepatocyte fatty acid metabolism 总被引:11,自引:0,他引:11
Bell JG McEvoy J Tocher DR McGhee F Campbell PJ Sargent JR 《The Journal of nutrition》2001,131(5):1535-1543
Duplicate groups of Atlantic salmon post-smolts were fed five practical-type diets in which the added lipid was 100% fish oil [FO; 0% rapeseed oil (0% RO)], 90% FO + 10% RO (10% RO), 75% FO + 25% RO (25% RO), 50% FO + 50% RO (50% RO) or 100% RO, for a period of 17 wk. There were no effects of diet on growth rate or feed conversion nor were any histopathological lesions found in liver, heart, muscle or kidney. The greatest accumulation of muscle lipid was in fish fed 0% RO, which corresponded to significantly lower muscle protein in this group. The highest lipid levels in liver were found in fish fed 100% RO. Fatty acid compositions of muscle lipid correlated with RO inclusion in that the proportions of 18:1(n-9), 18:2(n-6) and 18:3(n-3) all increased with increasing dietary RO (r = 0.98-1.00, P < 0.013). The concentrations of eicosapentaenoic acid [20:5(n-3)] and docosahexaenoic acid [22:6(n-3)] in muscle lipid were significantly reduced (P < 0.05), along with total saturated fatty acids, with increasing dietary RO. Diet-induced changes in liver fatty acid compositions were broadly similar to those in muscle. Hepatic fatty acid desaturation and elongation activities, measured using [1-(14)C] 18:3(n-3), were increased with increasing dietary RO. Limited supplies of marine fish oils require that substitutes be found if growth in aquaculture is to be maintained such that fish health and product quality are not compromised. Thus, RO can be used successfully as a substitute for fish oil in the culture of Atlantic salmon in sea water although at levels of RO >50% of dietary lipid, substantial reductions occur in muscle 20:5(n-3), 22:6(n-3) and the (n-3)/(n-6) polyunsaturated fatty acid (PUFA) ratio, which will result in reduced availability of the (n-3) highly unsaturated fatty acids that are beneficial for human health. 相似文献