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81.
Vandersea BA Ruvo AT Frost DE 《Oral and maxillofacial surgery clinics of North America》2007,19(3):351-68,vi
Management of transverse maxillary discrepancies poses treatment planning and postoperative challenges for surgeons and orthodontists. Multiple position papers have been written on the subject covering various aspects of nonoperative and surgical treatment and timing and stability issues. This article seeks not to propagate the debate of which procedure is better but rather to discuss appropriate indications for each in addition to their respective benefits and pitfalls. An historical perspective and the technical aspects of performing each operation are reviewed. 相似文献
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The present study examined self-concealment as a possible mediator in the relationship between perfectionism and distress. The study also explored whether willingness to disclose differed depending on whether the disclosure was to a friend, family member, or counselor. One hundred and sixteen undergraduate women were administered the Multidimensional Perfectionism Scale, the Self-Concealment Scale, the Hopkins Symptom Checklist-21, and the College Issues Questionnaire. Correlational analyses indicated that maladaptive perfectionism, self-concealment, and distress were all highly related. Path analysis indicated that self-concealment mediated the relationship between maladaptive perfectionism and distress. Willingness to discuss issues with family and friends was negatively correlated with maladaptive perfectionism and self-concealment, but unrelated to distress. These results indicate that a tendency to conceal negative personal information may be a significant contributor to the psychological distress experienced by those with maladaptive perfectionism. 相似文献
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Carrie Westmoreland Miller Julia A. Greenawalt Suzan Kardong‐Edgren Marilyn H. Oermann Margie Molloy Vickie Mudra Nancy Rogers Lissette Mondragon Anna Cespedes Erica Frost Regina Causey Suzanne Webb Annmarie Muana Allison Chen 《Nursing forum》2019,54(4):707-713
A 2‐year long, multisite research study that evaluated cardiopulmonary resuscitation skill decay among nursing students was conducted at 10 schools of nursing across the United States. The study was conducted in two phases and required carefully timed sessions for skill performance. Multisite studies in nursing education need to be carefully planned. Time delays should be anticipated with processes and Institutional Review Board protocols across sites. All team members were trained and consistently supported during the entire study. While challenges and obstacles were identified, innovative solutions were implemented that assisted the research team to successfully complete the study. The use of new and existing technology allowed the team to surmount many of the challenges encountered in this study. The purpose of this article is to describe the logistics, processes, challenges, and lessons learned related to conducting a complex multisite study. 相似文献
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Transforming growth factor beta (TGF-beta) is a potent and selective growth inhibitor of early hematopoietic progenitors and leukemic cells. The cellular mechanism(s) underlying this antiproliferative effect is, however, currently unknown. In the present study, we demonstrate that TGF-beta inhibits the expression of granulocyte-macrophage colony stimulating factor (GM-CSF), interleukin 3 (IL-3), and granulocyte-CSF (G-CSF) receptors on murine factor-dependent and independent hematopoietic progenitor cell lines without a significant change in receptor affinity. A maximum reduction in GM-CSF receptor numbers of 65% to 77% was observed by 96-hour incubation with TGF-beta. The TGF- beta induced trans-down-modulation of GM-CSF receptors was prolonged, noncytotoxic but reversible, and not due to endogenous production of GM- CSF. The TGF-beta induced reduction in CSF receptor numbers preceded TGF-beta's growth inhibitory action. In addition, the ED50 (1 to 10 pmol/L) for TGF-beta's CSF receptor modulatory and antiproliferative effect was similar. The effect of TGF-beta on cell surface CSF receptor expression was specific, because the expression of other cell surface proteins (Ly 5 and Ly 17) was not affected by TGF-beta treatment, and because other growth inhibitors (tumor necrosis factor and interferon) did not affect CSF receptor expression. These data suggest that the downregulation of the growth of hematopoietic progenitor cells by TGF- beta involves reducing the cell surface expression on growth factor receptors. 相似文献