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ObjectivesTo compare the amount of en-masse retraction with or without piezocision corticotomy, to assess the type of tooth movement, to evaluate root integrity after retraction, and to record reported pain levels.Materials and MethodsThis randomized, controlled clinical trial included 26 orthodontic patients requiring premolar extraction. The patients were divided into two groups: (1) an extraction with piezocision corticotomy group (PCG) and (2) an extraction-only group, which served as the control group (CG). Cone-beam computed tomography images were acquired before and 4 months after the initiation of en-masse retraction utilizing miniscrews. The following variables were assessed: the amount of en-masse retraction, incisor inclination, incisor and canine root resorption, and patient-reported pain.ResultsTwelve and 11 participants completed the entire study in the PCG and CG, respectively. The amount of en-masse retraction was significantly greater in the PCG compared to the CG (mean = 4.8 ± 0.57 mm vs 2.4 ± 0.33 mm, respectively [P < .001]). There was also significantly less tipping and root resorption of incisors in the PCG (P < .05). The reported pain was significantly higher on the first day in the PCG compared to the CG (P < .001); however, it became similar between the groups after 24 hours.ConclusionsPiezocision corticotomy enhanced the amount of en-masse retraction two times more with less root resorption. However, future studies are required to assess the long-term effects of this technique.  相似文献   
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The International Journal of Cardiovascular Imaging - In myocardial gated SPECT imaging each cardiac cycle is divided into 8 or 16 temporal frames and the cause of the difference between 8 and 16...  相似文献   
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To assess imaging data in COVID-19 patients and its association with clinical course and survival and 86 consecutive patients (52 males, 34 females, mean age?=?58.8 year) with documented COVID-19 infection were included. Seventy-eight patients (91%) were in severe stage of the disease. All patients underwent transthoracic echocardiography. Mean LVEF was 48.1% and mean estimated systolic pulmonary artery pressure (sPAP) was 27.9 mmHg. LV diastolic dysfunction was mildly abnormal in 49 patients (57.6%) and moderately abnormal in 7 cases (8.2%). Pericardial effusion was present in 5/86 (minimal in size in 3 cases and mild- moderate in 2). In 32/86 cases (37.2%), the severity of infection progressed from “severe” to “critical”. Eleven patients (12.8%) died. sPAP and computed tomography score were associated with disease progression (P value?=?0.002, 0.002 respectively). Tricuspid annular plane systolic excursion (TAPSE) was significantly higher in patients with no disease progression compared with those who deteriorated (P value?=?0.005). Pericardial effusion (minimal, mild or moderate) was detected more often in progressive disease (P?=?0.03). sPAP was significantly lower among survivors (P value?=?0.007). Echocardiographic findings (including systolic PAP, TAPSE and pericardial effusion), total CT score may have prognostic and therapeutic implication in COVID-19 patients.

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ObjectiveThe objective of this study was to determine the acceptance of a coronavirus disease 2019 (COVID-19) vaccine among the general adult population in Kuwait and assess its determinants.Subjects and MethodsA web-based cross-sectional study was conducted by enrolling adults living in Kuwait (n = 2,368; aged ≥21 years). Acceptance of a COVID-19 vaccine was inferred if participants indicated that they “definitely or probably will accept vaccination against COVID-19 once a vaccine is available.” Associations were explored by applying a modified Poisson regression to estimate and infer adjusted prevalence ratios (aPR) and their 95% confidence intervals (CI).ResultsIn total, 53.1% (1,257/2,368) of the participants were willing to accept a COVID-19 vaccine once available. Male subjects were more willing to accept a COVID-19 vaccine than females (58.3 vs. 50.9%, p < 0.001). Subjects who viewed vaccines in general to have health-related risks were less willing to accept vaccination (aPR = 0.39, 95% CI: 0.35–0.44). Moreover, participants who previously received an influenza vaccine were more likely to accept a COVID-19 vaccine (aPR = 1.44, 95% CI: 1.31–1.58). Willingness to get vaccinated against COVID-19 increased as the self-perceived chances of contracting the infection increased (p < 0.001).ConclusionOverall, 53.1% of the study participants demonstrated willingness to get vaccinated against COVID-19. We found several factors influencing the level of acceptance. Since vaccination appears to be an essential preventive measure that can halt the COVID-19 pandemic, factors relating to low vaccine acceptance need to be urgently addressed by public health strategies.  相似文献   
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