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The objective of this study was to evaluate the dentoskeletal changes consequent to orthodontic treatment in subjects with Class II subdivision malocclusions, treated with asymmetric extractions, compared with a normal-occlusion control group. The sample consisted of 3 groups, with 30 subjects in each: normal-occlusion subjects (group 1), untreated Class II subdivision subjects (group 2), and Class II subdivision patients treated with asymmetric extractions (group 3). All subjects had a full complement of permanent teeth at the beginning of treatment. The average ages of the subjects were 22.42, 15.76, and 18.57 years, respectively, in groups 1, 2, and 3. Measurements of relative differences in the spatial position of dental and skeletal bilateral landmarks were obtained from the submentovertex and posteroanterior cephalometric (PA) radiographs. The t test for independent samples was used to compare group 1 with groups 2 and 3 at different times. Results from the submentovertex radiograph showed that asymmetric extractions in Class II subdivision malocclusions will maintain the differences in the anteroposterior positions of right and left, maxillary and mandibular first molars, as would be expected with the treatment protocols used. There were no significant skeletal changes that could be attributed to the treatment approaches investigated or transverse collateral effects with the asymmetric mechanics used. It was also demonstrated that treatment of Class II subdivision malocclusions with asymmetric extractions produced corrections of maxillary and mandibular dental midline deviations with the midsagittal plane, without canting the occlusal plane or any other investigated horizontal plane, as seen in the PA radiograph. Treatment of Class II subdivision malocclusions with asymmetric extractions constitutes a beneficial approach to this problem.  相似文献   
23.
The production of chlamydospores is a diagnostic tool used to identify Candida albicans; these structures also represent a model for morphogenetic research. The time required to produce them with standard methods is 48-72 hours in rice meal agar and tensoactive agents. This time can be shorted using liquid media such as cornmeal broth (CMB) and dairy supplements. Five media were tested: CMB plus 1% Tween-80, CMB plus 5% milk, CMB plus 5% milk serum, milk serum, and milk serum plus 1% Tween-80, under different incubation conditions: at 28 degrees C and 37 degrees C in a metabolic bath stirring at 150 rpm, and at 28 degrees C in a culture stove. The reading time points were established at 8 and 16 hours. The best results were obtained at 16 hours with CMB plus 5% milk under incubation at 28 degrees C and stirring at 150 rpm. The next most efficient methods were CMB plus 5% milk serum and CMB plus 1% Tween-80, under the same incubation conditions. The other media were ineffective in producing chlamydospores. The absence of stirring at 28 degrees C prevented the formation of chlamydospores within the set time points, and incubation at 37 degrees C decreased their production. This paper reports that the time to form C. albicans chlamydospores can be reduced.  相似文献   
24.
Treatment stability is one of the most important objectives in orthodontics, but, despite decades of research, it is still agreed that the stability of aligned teeth is variable and largely unpredictable. This study aimed to evaluate the relapse of mandibular anterior crowding in patients treated without mandibular premolar extraction. The sample comprised 40 patients of both sexes with Class I or II malocclusions who received nonextraction treatment in the mandibular arch with edgewise mechanics. Lateral cephalograms and dental casts of each patient were obtained at pretreament, posttreatment, and 5 years postretention. Relapse of mandibular anterior crowding was assessed, and associations between this relapse and other clinical factors were also investigated. Mandibular anterior crowding was measured by the Little irregularity index, and the data were evaluated by the Mann-Whitney test. The mean relapse of mandibular anterior crowding was 1.95 mm (26.54%) over the long term. No clinical factor studied was predictive of crowding relapse in the long term.  相似文献   
25.
Y zeolites with different sodium contents and a sodium mordenite were evaluated as support for bis(cyclopentadienyl)zirconium dichloride as catalyst for ethylene polymerization. The results showed that, although the activities of the supported catalysts were lower than that of the homogeneous system, the average molecular weight of the polyethylene produced from the former was in general much higher than that of the polymer produced in solution. Contrary to the expected trend if the specific area was the dominant factor for catalyst activity, the best catalyst was the one supported on NaM zeolite. Thus, our results indicate that the concentration of framework aluminium atoms is the dominant factor, but that the contribution of the external surface is also important.  相似文献   
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Thirty-five cardiomyoplasty procedures were performed in five patients with dilated and 30 patients with ischemic cardiomyopathies. Russian-made cardiomyostimulators (CMS) were implanted in these patients. Twenty-one patients underwent a one-step procedure using a left thoracotomy for cardiomyoplasty, while in 14 patients, a two-step procedure that included a mid-line sternotomy was carried out. During the average follow-up period of 9 ± 2.1 months, studies were carried out that showed in survivors improved clinical functional status and decreased heart failure symptoms. Evidence of revascularization of the ischemic myocardium from the latissimus dorsi muscle (LDM) wrap was obtained by angiography and radioactive scintigraphy. In five patients, the CMS had to be removed due to complications, and in all these patients, their clinical functional status deteriorated following the cessation of cardiomyostimulation.  相似文献   
28.
A group of destructive changes occurring in jaws in patients with maxillary complete dentures and mandibular removable partial dentures (bilaterally) has been described in the literature as the combination syndrome. However, this condition is not clinically observed in all patients. The aim of this study was to establish the prevalence index on signs of combination syndrome and to verify whether these changes also occurred in patients rehabilitated with a mandibular removable partial denture (unilaterally). Sample was composed of 44 patients, completely edentulous in the maxilla. Thirty-two patients had a Kennedy Class I removable partial denture and 12 a Kennedy Class II. Three major alterations were observed in 20.5% of the studied population. Nevertheless, these changes were present only in 25% of patients with Kennedy Class I removable partial denture. Based on the findings of this study, it can be concluded that patients with Kennedy Class II removable partial denture do not have similar signs that lead to the combination syndrome’s condition.  相似文献   
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Intravascular "mulberry-like" bodies in a stillborn female infant with moderate maceration are reported. The histogenesis of these structures is discussed based on light-microscopic, immunohistochemical and ultrastructural findings. No demonstrable causal relation between the intravascular lesions and fetal death was found, the cause of death being attributed to intrauterine asphyxia. It is concluded, that intravascular "mulberry-bodies" most likely represent artifacts due to red blood cell autolysis.  相似文献   
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