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71.
The present study evaluated the reliability and validity of the Triage Assessment Survey: Organizations (TAS:O), a 27-item, 5-point, Likert summated rating scale. One hundred and seventeen participants responded to the TAS:O after reading mild, moderate, marked and severe organizational crisis scenarios. The overall Cronbach's alpha and split-half reliability were both .93. Confirmatory factor analysis revealed three factors, supporting the hypothesis that the TAS:O is comprised of three distinct factors (i.e., Affect, Behavior, and Cognition). An analysis of variance provided evidence that the TAS:O has the capacity to distinguish among mild, moderate, marked, and severe crises. Because this research is the first to evaluate the TAS:O, further studies are needed to strengthen confidence in the psychometric properties of this scale.  相似文献   
72.
Recent evidence indicates few differences between patients recruited through advertising and by consultation referral, and there is some suggestion that those recruited through advertising are more representative of the target community population. However little has been reported on differences in placebo response and compliance in these two patient groups. We conducted a retrospective chart review of 49 patients with major depressive disorder (MDD), recruited through advertising or consultation, randomized to placebo in five clinical trials. Variables included demographics, clinical history, efficacy, compliance, and completion data. Homogeneity was demonstrated for most variables. Differences in placebo groups included significantly lower Hamilton Rating Scale for Depression (HAM-D) scores for the advertisement group throughout the trials. Advertisement patients were also more likely to be early placebo responders and in remission at Days 14 and 28. No differences were found in completion rates or reasons for early termination. Compliance was excellent for both groups. Early placebo response of the advertisement group reinforces the need for trials of at least 8 weeks. In addition, consultation patients may have a more severe illness and be treatment resistant, suggesting they are less generalizable to community practice populations.  相似文献   
73.
Volatile anaesthetics have historically been considered to act in a nonspecific manner on the central nervous system. More recent studies, however, have revealed that the receptors for inhibitory neurotransmitters such as gamma-aminobutyric acid (GABA) and glycine are sensitive to clinically relevant concentrations of inhaled anaesthetics. The function of GABA(A) and glycine receptors is enhanced by a number of anaesthetics and alcohols, whereas activity of the related GABA rho1 receptor is reduced. We have used this difference in pharmacology to investigate the molecular basis for modulation of these receptors by anaesthetics and alcohols. By using chimaeric receptor constructs, we have identified a region of 45 amino-acid residues that is both necessary and sufficient for the enhancement of receptor function. Within this region, two specific amino-acid residues in transmembrane domains 2 and 3 are critical for allosteric modulation of both GABA(A) and glycine receptors by alcohols and two volatile anaesthetics. These observations support the idea that anaesthetics exert a specific effect on these ion-channel proteins, and allow for the future testing of specific hypotheses of the action of anaesthetics.  相似文献   
74.
A 2 cm long three-contact multisection laser has been fabricated for modelocking at very low repetition rates. Active modelocking yields 8.0-12.3 ps pulses at 2.2, 4.3 and 6.5 GHz corresponding to the fundamental, first, and second harmonics of the cavity resonance frequency. This device demonstrates the feasibility of fabricating monolithic pulse sources operating at rates as low as the OC-48 Sonet transmission rate (2.488 Gbit/s).<>  相似文献   
75.
76.
In response to public concern over abuses in human medical experimentation, the dominant approach to the ethics of clinical research during the past 30 years has been regulation, particularly via institutional review board review and approval of scientific protocols and written consent forms. However, the effectiveness of regulatory mechanisms in ensuring the ethical conduct of clinical research is limited. Little attention has been devoted to the nature and role of professional integrity of physician investigators, a conscientious framework for guiding investigators in the socially important but morally complex activity of clinical research. Professional integrity is vital in forging an ethically sound relationship between investigators and patient volunteers, a relationship that differs in important ways from the patient-physician relationship in standard clinical practice. We examine critically 2 models of the moral identity of physician investigators, the investigator as clinician and the investigator as scientist; in neither of these 2 models can the physician investigator eliminate completely the moral conflicts posed by clinical research. The professional integrity of physician investigators depends on a coherent moral identity that is proper to the enterprise of clinical research. The roles of clinician and scientist must be integrated to manage conscientiously the ethical complexity, ambiguity, and tensions between the potentially competing loyalties of science and care of volunteer patients.  相似文献   
77.
The known effects of commonly used nonsteroidal anti-inflammatory drugs (NSAIDs) on hemostatic parameters have led to concern over their use in the perioperative period. Nabumetone, unlike other NSAIDs, has little effect on collagen-induced platelet aggregation. To evaluate the effect of nabumetone 2000 mg daily on other hemostatic parameters (e.g., bleeding time, prothrombin time, and partial thromboplastin time) in the clinical setting, this double-masked study was conducted in patients with osteoarthritis undergoing arthroscopic knee surgery. After a 1-week placebo washout period, 58 patients were randomized to receive nabumetone and 53 were randomized to receive placebo. They were assessed before surgery (after 1 to 2 weeks of treatment) and again after surgery (after an additional 3 weeks of treatment). The study was designed to have 90% power to show equivalence in bleeding time to within 1.5 minutes, a difference assumed to be of no clinical importance. No meaningful differences were observed between the groups in any of the measured hemostatic parameters. Before surgery, the bleeding time increased by only 0.3 minutes with nabumetone and decreased by 0.2 minutes with placebo. The mean (+/- SD) difference between the groups in change from baseline was 0.5 +/- 0.3 minutes. After surgery, the changes were 0.1 minutes and 0.0 minutes, respectively, and the difference between groups was 0.2 +/- 0.3 minutes. These differences were neither statistically nor clinically significant, and maximum individual increases were similar in each group. Furthermore, there were no reports of abnormal bleeding in the operative knees. The results of this study show that nabumetone had little or no effect on hemostasis and suggest that this drug can be used safely in the perioperative period.  相似文献   
78.
The specification of vowel formant bandwidths for speech synthesis has been inconsistent in the past, perhaps due to the difficulty of measuring formant bandwidths in natural speech and the possible perceptual insignificance of formant bandwidths on the intelligibility of synthetic speech. Here, regression equations are presented for the estimation of formant bandwidths based on measurements from natural speech which is based only on formant center frequency and independent of other formant values. Current usage, as well as comparison with another well-known estimation algorithm suggests that the new procedure should be quite acceptable for some types of speech synthesis.  相似文献   
79.
A restructured electricity system may undervalue renewable energy. We remain wary of unregulated markets, but urge the renewable energy community to begin considering how they could adapt to increasing customer choice.  相似文献   
80.
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