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161.
Responsiveness, the ability to detect meaningful clinical change, is a critical attribute of instruments used to evaluate outcomes of treatments. The authors hypothesized that self-administered symptom severity and functional status questionnaires are more responsive to clinical improvement after carpal tunnel release than traditional physical examination measures of strength and sensibility. Data were obtained from a randomized clinical trial of endoscopic versus open carpal tunnel release conducted in four university medical centers. Patients were evaluated before surgery and 3 months after surgery. Seventy-four patients indicating that they were more than 80% satisfied with the results of surgery were assumed to have clinically meaningful improvement and were the focus of the analysis. Evaluations included questionnaires assessing symptom severity, functional status, and activities of daily living as well as measurement of grip, pinch, and abductor pollicus brevis strength, and 2-point discrimination and Semmes-Weinstein pressure sensibility. Responsiveness was calculated with the standardized response mean (mean change/standard deviation of change) as well as the effect size (mean change/standard deviation of baseline values). The symptom severity scale was four times as responsive, and the functional status and activities of daily living scales were twice as responsive, as the measures of strength and sensibility. Self-administered symptom severity and functional status scales are much more responsive to clinical improvement than measures of neuromuscular impairment and should severe as primary outcomes in clinical studies of therapy for carpal tunnel syndrome.  相似文献   
162.
163.
Examined the effects of counselor note-taking behavior on participants' impressions of a counselor during a career counseling session. A total of 140 participants (70 men and 70 women) rated 1 of 2 videotapes designed to credibly simulate a real career counseling interview. Note-taking was the independent variable. Results of this study suggest that whether a counselor is observed in a note-taking or non-note-taking condition has no significant effect on perceived counselor expertness, attractiveness, or trustworthiness. However, there was a significantly greater willingness of the participants to see the counselor who refrained from note-taking. Results offer tentative suggestions for those counselors who choose to take notes during a career counseling session. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
164.
The chromosomal observations in a cultured primary epidermoid carcinoma of the parotid gland are reported. The tumour had a flat hyper-triploid mode with 7 recurrent wholly or partially identified marker types and 7-13 additional, mostly recurrent, markers, whose origin could not be clarified. There were also many recurring numerical deviations in most tumour cells. The picture was consistent with a neoplasma in an advanced stage of chromosomal progression. So far, 6q-markers with varying morphology are the only deviations found in most types of malignant salivary tumours and, in particular, in a high percentage of adenoid-cystic carcinomas. One possible explanation for these observations is the occurrence of one or more suppressor genes in 6q which may have relevance for malignant neoplasia in salivary gland tissues.  相似文献   
165.
A case involving multiple bite marks is presented. The bite marks were photographed over a 31-day period to document the injuries and preserve their evidentiary value. The evidence recovered at each photography session is discussed and photographs are presented for review. Suggestions concerning the need for more research are presented.  相似文献   
166.
Job postings and the decision to interview: A verbal protocol analysis.   总被引:1,自引:0,他引:1  
Investigated the process of deciding whether or not to apply for jobs, using the verbal protocol analysis (VPA) technique. Verbal reports provided by participants as they evaluated job postings and decided whether or not to interview for jobs were analyzed to assess what information was heeded, the impact of incomplete or unusual information, and the role of inferences regarding job characteristics and probability of hire. Results indicated that location and compensation received the most attention and that participants also responded to the amount of information provided. In addition, participants made inferences about unobserved characteristics and probability of hire, although the latter played little role in the decision to interview. The study also provided support for the usefulness of VPA by demonstrating that neither the verbal protocol process nor the use of prompts significantly influenced participants' decisions (as compared with the decisions of control groups). (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
167.
The crystalline phase development and microstructural changes with heating of sol-gel-derived lead titanate (PT) particles and films on silica with and without a fugitive (or removable) diffusion barrier layer were investigated. Amorphous gel-derived PT particles were deposited on SiO2-coated TEM grids with and without polyimide (PI) or carbon barrier layers between SiO2 and PT. TEM analysis showed that PI or carbon barriers prevented reaction between the gel-derived PT particles and SiO2. PT particles crystallize and then the PI or carbon film decomposes. Sol-gel-derived PT films were deposited on oxidized Si substrates (Si/SiO2) with and without a PI barrier layer. Perovskite PT films were prepared on Si/SiO2 substrates with a PI barrier; however, some porosity remained in the films. Identically prepared films without the PI barrier formed a mixture of pyrochlore and perovskite. X-ray photoelectron spectroscopy results indicate that the PI film pre- vents the diffusion of Si into the PT film.  相似文献   
168.
beta2-Integrin adhesion molecules play crucial roles in monocyte transmigration and adherence to the inflamed extracellular matrix. While integrin engagement contributes to inflammatory cell activation, little is known about the precise signaling pathways that are important to integrin-dependent monocyte activation. We examined the role of tyrosine phosphorylation and extracellular-signal regulated kinase (ERK) activity in beta2-integrin signaling in monocytes. Cross-linking of the LFA-1 (CD11a/CD18) and MAC-1 (CD11b/CD18) integrins on the surface of THP-1 monocytic cells induced the accumulation of tyrosine phosphoproteins. As part of this signal both ERK-1 and ERK-2 are tyrosine phosphorylated. In vitro kinase assays documented an increase in ERK-2 activity following both LFA-1 and MAC-1 cross-linking. beta2-Integrin cross-linking also led to a marked increase in 4-h procoagulant activity (PCA) in THP-1 cells and purified human monocytes. Inhibition of tyrosine phosphorylation by genistein (10 microg/ml), or selective ERK inhibition with PD98059 (10 microM), was able to block the integrin-dependent induction of PCA in both THP-1 cells and human monocytes. Thus, beta2 integrin signaling in monocytic cells can flow through the tyrosine phosphorylation and activation of the ERK mitogen activated protein kinases, which is essential for the subsequent expression of tissue factor. These results suggest that the ERK proteins likely function to integrate various adhesion-dependent signals during the process of monocyte transmigration.  相似文献   
169.
A series of quench tests on hollow cylindrical specimens made of the machinable ceramic, Pyrophyllite, has been performed. The specimens consistently fractured with two diametrically opposite longitudinal cracks. Finite element analysis indicates that the primary crack occurred at the stage when the strain energy of the cylinder reached its maximum during the thermal transient process, while the secondary crack was caused by stress waves generated following the primary crack. This is supported by experimental observation of the time of fracture and the crack morphology. The work reported here helps to shed light on the fracture criterion for brittle cylindrical components under transient thermal and dynamic loadings.  相似文献   
170.
Fast, large-scale model predictive control by partial enumeration   总被引:1,自引:0,他引:1  
Partial enumeration (PE) is presented as a method for treating large, linear model predictive control applications that are out of reach with available MPC methods. PE uses both a table storage method and online optimization to achieve this goal. Versions of PE are shown to be closed-loop stable. PE is applied to an industrial example with more than 250 states, 32 inputs, and a 25-sample control horizon. The performance is less than 0.01% suboptimal, with average speedup factors in the range of 80-220, and worst-case speedups in the range of 4.9-39.2, compared to an existing MPC method. Small tables with only 25-200 entries were used to obtain this performance, while full enumeration is intractable for this example.  相似文献   
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