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Abstract

Objective

Two similarly designed studies compared user experiences with a second-generation extra-thin-wall, 5-bevel 32?G?×?4?mm pen needle (PN) with redesigned hub versus four thinner commercially available PNs.  相似文献   
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Do miniscrews remain stationary under orthodontic forces?   总被引:11,自引:0,他引:11  
Miniscrews have been used in recent years for anchorage in orthodontic treatment. However, it is not clear whether the miniscrews are absolutely stationary or move when force is applied. Sixteen adult patients with miniscrews (diameter = 2 mm, length = 17 mm) as the maxillary anchorage were included in this study. Miniscrews were inserted on the maxillary zygomatic buttress as a direct anchorage for en masse anterior retraction. Nickel-titanium closed-coil springs were placed for the retraction 2 weeks after insertion of the miniscrews. Cephalometric radiographs were taken immediately before force application (T1) and 9 months later (T2). The cephalometric tracings at T1 and T2 were superimposed for the overall best fit on the structures of the maxilla, cranial base, and cranial vault to determine any movement of the miniscrews. The miniscrews were also evaluated clinically for their mobility (0: no movement, 1: < or =0.5 mm, 2: 0.5-1.0 mm, 3: >1.0 mm). The mobility of all miniscrews was 0 at T1 and T2. On average, the miniscrews tipped forward significantly, by 0.4 mm at the screw head. The miniscrews were extruded and tipped forward (-1.0 to 1.5 mm) in 7 of the 16 patients. Miniscrews are a stable anchorage but do not remain absolutely stationary throughout orthodontic loading. They might move according to the orthodontic loading in some patients. To prevent miniscrews hitting any vital organs because of displacement, it is recommended that they be placed in a non-tooth-bearing area that has no foramen, major nerves, or blood vessel pathways, or in a tooth-bearing area allowing 2 mm of safety clearance between the miniscrew and dental root.  相似文献   
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Chronic graft-versus host disease (GVHD) is a chronic and disabling complication after hematopoietic cell transplantation (HCT). It is important to understand the association of socioeconomic status (SES) with health outcomes in patients with chronic GVHD because of the impaired physical health and dependence on intensive and prolonged health care utilization needs in these patients. We evaluated the association of SES with survival and quality of life (QOL) in a cohort of 421 patients with chronic GVHD enrolled on the Chronic GVHD Consortium Improving Outcomes Assessment study. Income, education, marital status, and work status were analyzed to determine the associations with patient-reported outcomes at the time of enrollment, nonrelapse mortality (NRM), and overall mortality. Higher income (P?=?.004), ability to work (P?<?.001), and having a partner (P?=?.021) were associated with better mean Lee chronic GVHD symptom scores. Higher income (P?=?.048), educational level (P?=?.044), and ability to work (P?<?.001) also were significantly associated with better QOL and improved activity. In multivariable models, higher income and ability to return to work were both significantly associated with better chronic GVHD Lee symptom scores, but income was not associated with activity level, QOL, or physical/mental functioning. The inability to return to work (hazard ratio, 1.82; P?=?.019) was associated with worse overall mortality, whereas none of the SES indicators were associated with NRM. Income, race, and education did not have statistically significant associations with survival. In summary, we did not observe an association between SES variables and survival or NRM in patients with chronic GVHD, although we found some association with patient-reported outcomes, such as symptom burden. Higher income status was associated with less severe chronic GVHD symptoms. More research is needed to understand the psychosocial, biological, and environmental factors that mediate this association of SES with major HCT outcomes.  相似文献   
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