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The use of different approaches to measurement in drug abuse treatment outcome studies has resulted in a lack of comparability across studies. This paper reviews different approaches to timing of baseline and follow-up periods and to dealing with time periods during which follow-up subjects are not "at risk" for drug use. Length and timing of baseline and follow-up periods are considered as well as periods of time within which specific drug use outcomes are measured. It is suggested that research focus on describing the natural course of drug use both prior to and following treatment, in order to determine the most appropriate length and timing of follow-up periods. It is recommended that investigators report drug use data from both "at risk" and "not at risk" periods, and that they choose methods of controlling for time "at risk" which do not eliminate important drug use data from analyses. 相似文献
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T A Benke J W Clark P J Wisoff S Schneider C Balasubramaniam H K Hawkins J Laurent L Perling A Shehab 《Lasers in surgery and medicine》1989,9(6):602-615
Conventional suture repair of peripheral nerves results in a fibrotic reaction that is detrimental to nerve regeneration. As an alternative procedure known as "laser-assisted" repair, a laser can be used, along with a reduced number of sutures, to reanastomose served peripheral nerves. To explore the long-term implications of this technique, the right sciatic nerves of Sprague-Dawley rats were surgically cut and reanastomosed either by means of four epineurial sutures or two epineurial sutures and CO2 laser welds. Tensile strength, electrophysiology, histology, and functional studies were performed up to 11 months postoperatively. Tensile strength measurements indicate no long-term disadvantage with the laser-assisted technique, although the short-term tensile strength is lower than with conventional suture repair. The conduction velocities of the repaired nerves were similar for both techniques; however, laser-assisted repaired nerves were found to have lower stimulation thresholds and reduced branching compared to the suture repaired nerves. The measured functional recovery was similar for both repair techniques. 相似文献
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Eileen Mary Grealish Robert P. Hawkins Pamela Meadowcroft Pamela Weaver Sharon S. Frost Percilla Lynch 《Child & youth care forum》1989,18(1):49-61
Many youth, their parents, and social services regard the unification of the family as the most desirable outcome for youth in out-of-home placements. This goal is often difficult to achieve because the families of these troubled/troubling youths are often severely dysfunctional, with multiple problems. A group process model for serving natural parents of youth in placement is described which, in conjunction with one-on-one interactions with professionals, appears to have a positive impact on these families and on youths' return home. Group components that seem particularly important are described, including attendance by invitation only, public commitment to attend and participate, reminder prompts, transportation support, babysitting support, refreshments, opportunity to visit with their child, defined staff roles, an empowering approach, and starting where the parent is. The group process maintained a relatively high level of both attendance and participation by the targeted parents. Participants tended to achieve most goals that they set in the group. Our experience indicates that interventions with natural parents of troubled youth can enable even a very dysfunctional family to improve enough to receive youth back into their home.The authors are grateful for the assistance of Sharon Estill, Jim Bernardo, Anita Mentzer, Dave Walker, and Suni Dague-Lyman for assistance in collecting the data reported here. Debbie Buchanan and others have been a great assistance in transporting families. 相似文献
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Sanjana VM; Johnston PA; Robertson CR; Jamison RL 《The American journal of physiology》1976,231(2):313-318
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