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51.
CG Dais J Prazma SS Ball C Zdanski V Carrasco HC Pillsbury 《Canadian Metallurgical Quarterly》1996,99(1-2):1-6
OBJECTIVE: Trials that do not allow rejection of the null hypothesis of no treatment effect may have had an inappropriate design. Trials are virtually never assessed for correlation between responses to different treatment modalities. METHODS: Using a hypothetical example and several published studies we examine the influence of correlation levels between treatment modalities on the sensitivity of testing. RESULTS: The level of correlation between responses to different treatment modalities is a major determinant of the sensitivity both of crossover and parallel group clinical trials. CONCLUSIONS: It is very relevant to assess a priori correlation levels between responses to the different treatment modalities of a trial. If a negative correlation is anticipated, a crossover design is likely to lack sensitivity. If a positive correlation is anticipated a parallel-group design seems less appropriate, because it would lack the extra sensitivity of accounting for the positive correlation. Both designs would seem suitable for approximately zero correlations (e.g. comparison vs baseline or vs placebo under the assumption that the number of placebo responders is negligible. 相似文献
52.
53.
Monolithic Catalysts with Low Noble-Metal Content for Exhaust Purification of Small Gasoline Engines
A series of low noble-metal coment monolithic catalysts for exhaust purification of small gasoline engines was investigated, and it was found that the Pt/Rh-OSM/Al2O3 (where OSM was oxygen storage material) catalyst with Ce0.5Zr0.5-MnOx(3%MnOx) OSM held low light-off temperature for CO, HC, and NO; quite wide three-way window, and outstanding thermal stability. The catalyst could efficiently comrol exhaust emission of small gasoline engines. 相似文献
54.
IM McAleer GW Kaplan HC Scherz MG Packer FP Lynch 《Canadian Metallurgical Quarterly》1993,42(5):563-7; discussion 567-8
Trauma is the major source of mortality in the pediatric population. A retrospective review was performed on patients admitted to the Children's Hospital and Health Center Trauma Program, San Diego, California, from August 1984 to May 1990. The purpose of this review was to evaluate pediatric trauma and to determine the best treatment and evaluation for genitourinary injuries. Blunt trauma was responsible for 98 percent of the injuries, with renal injuries being the most common. Bladder (7) and male urethral (2) injuries, and vaginal lacerations (8) also occurred. The most severe renal injuries (70%) and all significant bladder and urethral injuries were associated with gross hematuria. Hypotension was present in 31 percent of patients but rarely required surgical exploration for correction. Eighty-six patients underwent radiographic imaging. Computerized tomography (CT) scans demonstrated the most information about intra-abdominal solid organ injuries but was inaccurate in detecting bladder or urethral injuries. Genitourinary injury is common in children but rarely requires surgical management. CT scan is the best study to determine extent of solid-organ injury but is inferior to cystourethrography to diagnose bladder or urethral injuries. 相似文献
55.
Lawrence E. Holloway Yu Gong Jeff Ashley 《Mathematics and computers in simulation》2006,70(5-6):275-286
This paper introduces the concepts of state observability and condition observability for condition systems, a class of systems composed of discrete state components which interact via discrete binary signals called conditions. Given a set of externally observed conditions, state observability implies that the state of the system can be determined from the observations, and condition observability implies that all unobserved input and output conditions of the system can be determined from the observations. In this paper, we present a class of systems which is state observable and condition observable. We present a method to synthesize an observer system to provide state and condition signal estimates for a single component subsystem. 相似文献
56.
BACKGROUND: While monotherapy has significant limitations in bipolar disorder, few published data addressing alternatives exist. Treatment algorithms have been proposed, but none have undergone empirical evaluation. This study provides a systematic prospective, open evaluation of the effectiveness and tolerability of a treatment algorithm for patients with histories of mania. METHOD: Twenty-eight symptomatic outpatients from a public mental health facility who were diagnosed as having either bipolar I or schizoaffective illness, bipolar type, entered the study. Minimum blood levels of lithium and divalproex sodium were defined. Medications were pushed to predetermined levels (as tolerated) before proceeding to the next algorithm step. Clinical symptoms were assessed monthly using the Brief Psychiatric Rating Scale (BPRS, 27 item) and Clinical Global Impressions scale. RESULTS: Pretreatment and posttreatment clinical symptoms were compared. Over 50% of patients attained 30% improvement from baseline BPRS after 4 months. Thirty-six percent of patients (N = 10) became mood stable, 46% (N = 13) remained mood unstable, and 18% (N = 5) dropped out before completing the algorithm. Although patients who finished the algorithm were taking more medication, either dosage and/or drugs, somatic complaints did not increase. CONCLUSION: The potential benefit of a defined treatment algorithm was demonstrated for these complex and persistently ill patients. Despite long treatment histories, patients improved with more frequent visits and addition of medication(s). A randomized controlled trial comparing a similar treatment algorithm with treatment-as-usual is warranted. 相似文献
57.
This study describes the isolation and characterization of zebrafish homologues of the mammalian Pax3 and Pax7 genes. The proteins encoded by both zebrafish genes are highly conserved (>83%) relative to the known mammalian sequences. Also the neural expression patterns during embryogenesis are very similar to the murine homologues. However, observed differences in neural crest and mesodermal expression relative to mammals could reflect some functional divergence in the development of these tissues. For the zebrafish Pax7 protein we report the first full-length amino acid sequences in vertebrates and show the existence of three additional isoforms which have truncations in the homeodomain and/or the C-terminal region. These novel variants provide evidence for additional isoform diversity of vertebrate Pax proteins. 相似文献
58.
59.
Benign mesenchymal tumours of the bladder are rare, accounting for only 1-5% of bladder neoplasms. We describe what appears to be the first reported case of massive bleeding from a leiomyoma of the urinary bladder causing tamponade requiring emergency surgery. 相似文献
60.
JA Weidanz KF Card A Edwards E Perlstein HC Wong 《Canadian Metallurgical Quarterly》1998,221(1-2):59-76
The ability to display functional T-cell receptors (TCR) on the surface of bacteriophage could have numerous applications. For instance, TCR phage-display could be used to develop new strategies for isolating TCRs with unique specificity or it could be used to carry out mutagenesis studies on TCR molecules for analyzing their structure-function. We initially selected a TCR from the murine T-cell hybridoma, DO11.10, as our model system, and genetically engineered a three domain single-chain TCR (scTCR) linked to the gene p8 protein of the Escherichia coli bacteriophage fd. Immunoblotting studies revealed that (1) E. coli produced a soluble scTCR/p8 fusion protein and (2) the fusion protein was packaged by the phage. Cellular competition assays were performed to evaluate the functionality of the TCR and showed the DO11.10 TCR-bearing phage could significantly inhibit stimulation of DO11.10 T hybridoma cells by competing for binding to immobilized MHC/peptide IA(d)/OVA(323-339). Flow cytometric analysis was carried out to evaluate direct binding of DO11.10 TCR-bearing phage onto the surface of cells displaying either IAd containing irrelevant peptide or OVA peptide. The results revealed binding of DO11.10 TCR-bearing phage only on cells expressing IA(d) loaded with OVA peptide showing TCR fine specificity for peptide. To illustrate the generality of TCR phage-display, we also cloned and displayed on phage a second TCR which recognizes a peptide fragment from human tumor suppressor protein p53 restricted by HLA-A2. These findings demonstrate functional TCR can be displayed on bacteriophage potentially leading to the development of novel applications involving TCR phage-display. 相似文献