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991.
OBJECTIVE: To test the hypothesis that there are no significant differences in the shear bond strength or the adhesive remaining on the tooth after debonding between precoated and uncoated brackets using a self-etching primer. MATERIALS AND METHODS: APC Plus precoated brackets and uncoated brackets were bonded with Transbond XT adhesive using the self-etching primer Transbond Plus Self-Etching Primer (TPSEP). The brackets were bonded to extracted human premolars and categorized into two groups: (1) TPSEP/Transbond XT and (2) TPSEP/APC Plus. Shear bond strength was measured with a universal testing machine. The adhesive remnant on each tooth after debonding was quantified with image analysis equipment. Scanning electron microscope (SEM) observations of enamel surfaces treated with TPSEP were also carried out. RESULTS: No significant differences were observed in the shear bond strengths for the two groups evaluated (P < .05). TPSEP/APC Plus left significantly less adhesive on the tooth after debonding than did TPSEP/Transbond XT (P < .05). It was observed that SEM left a porous and potentially retentive surface. CONCLUSIONS: There was no significant difference in the bond strength of the two systems tested, but there was a significant difference in the percentage of area of adhesive remaining on the tooth.  相似文献   
992.
OBJECTIVE: To evaluate the position of the mandibular first permanent molar in the mandible relative to several factors. MATERIALS AND METHODS: A total of 185 untreated Class I and Class II patients were randomly selected from a sample of 350 patients from a single office. The palatal and mandibular planes were related to Frankfort horizontal to create the interjaw or "B" angle. Age and the mesial contact of the mandibular first molars were used. The landmarks were projected at right angles to the Frankfort horizontal for effective mandibular dimension lengths. Actual-length dimensions were projected at right angles to the mandibular plane. Pearson product moment correlation coefficients were computed to evaluate the effect of age, cranial length, and mandibular contribution to the molar's sagittal position in the mandible. Significance was reported only when P < .05 to determine a 95% confidence level. RESULTS: Statistically significant positive correlations indicated that the mandibular molar is located more forward with increasing age, longer mandibular body length, and increasing posterior facial height. In contrast, significant negative correlations to the interjaw, mandibular plane, ramal inclination angles, and the linear ramal contribution corresponded to a more posterior position of the molar with increasing angles. CONCLUSIONS: The mandibular first permanent molar is located more anteriorly with an older patient, a longer mandibular body, greater posterior facial height, and an acute interjaw angle. In contrast, an increase in the forward tip of the ramus places the molar in a more posterior location.  相似文献   
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BackgroundReverse total shoulder arthroplasty (rTSA) improves shoulder elevation in patients treated for cuff tear arthropathy (CTA) or irreparable massive cuff tears. Patient satisfaction can be limited by reduced active external rotation (AER). Rotator cuff muscles that externally rotate the shoulder are infraspinatus and teres minor (TM).AimThe purpose of this study was to assess the correlation between preoperative TM fatty degeneration and postoperative AER after rTSA performed for CTA or irreparable cuff tears.MethodsConstant scores and active range of motion were consecutively collected for 109 shoulders in 97 patients (mean: 75.73 ± 8.94 years; 31 male, 66 female) over a 10-year period. AER was evaluated with the humerus in adduction (AER1) and in abduction. TM muscle atrophy was scored according to Goutallier's classification, assessed on preoperative computed tomography scans.ResultsMultivariate analysis showed that TM fatty infiltration was a predictor of AER1. AER1 decreased by 4.9 degrees preoperatively and by 6.4 degrees at the final follow-up, for each increment in Goutallier grade (P = .02). Postoperatively, AER evaluated with humerus in abduction improved significantly (P < .001), but did not correlate with TM Goutallier grade. At a mean follow-up of 38 months (range: 24 to 96), mean Constant score improved from 20.5 ± 11.1 to 68.4 ± 14.9 (P < .001), as did shoulder active range of motion in all planes including AER1 (P < .001).ConclusionThis is the first study to quantify the inverse correlation between AER and TM Goutallier grade, both preoperatively and after rTSA; this information guides prognosis for patients with TM degeneration undergoing rTSA. Further studies are necessary to have a better understanding and find reliable solutions.Level of evidenceLevel III; Case Series  相似文献   
995.

Primary intraventricular hemorrhage (PIVH) is a special subtype of intraventricular hemorrhage (IVH) without a hemorrhagic parenchymal component. Different conditions may cause this uncommon hemorrhage including trauma, vascular anomalies, coagulation disorders, and others. Frequently, PIVH is associated with structural vascular anomalies such as aneurysms, arteriovenous malformations, and dural fistulas. Traditionally, hypertension has been considered a predisposing factor for PIVH. A wide variety of studies have been published describing patients with PIVH; however, studies describing exclusively patients with hypertensive PIVH are lacking in the literature. For this reason, the features of PIVH secondary to hypertension are not well described. The purpose of this study is to analyze and describe the characteristics of hypertensive PIVH. A PubMed and Scopus search adhering to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines was performed to include studies reporting patients with hypertensive PIVH. The search yielded 19 articles reporting retrospective case series. The diagnosis of hypertensive PIVH should be established in patients meeting the following criteria: (a) elevation of blood pressure is observed at admission, (b) a cerebral angiography is negative for vascular anomalies, and (c) other causes of intracranial hemorrhage are ruled out. The prognosis is poorer in patients who present with low Glasgow Coma Score (GCS), old age, hydrocephalus, or more extensive intraventricular bleeding. The results of this study show that hypertension is the most common cause of PIVH, followed by hemorrhage caused by vascular anomalies. Hypertension may be a direct cause of PIVH, but also it may be a predisposing factor for bleeding in cases of an associated vascular anomaly.

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996.
The in vitro activity of ketolide HMR 3647 against coryneform bacteria isolated from clinical samples was evaluated. Except against Corynebacterium jeikeium and C. urealyticum, HMR 3647 showed high activity against Corynebacterium spp., being more active than 14- and 16-membered macrolides, azithromycin, or clindamycin. HMR 3647 also had high in vitro activity against Brevibacterium spp. and Listeria monocytogenes.  相似文献   
997.
OBJECTIVE: To compare the diagnostic performance of transvaginal color Doppler sonography (TVCD) and sonohysterography (SHG) in the diagnosis of endometrial polyps. METHODS: Fifty-one women (mean age, 51 years; range, 27-75 years) with clinical or B-mode sonographic suspicion of endometrial polyps were included in this prospective study. Transvaginal color Doppler sonography first and then SHG were performed in all patients. On TVCD, a polyp was suspected when a vascular pedicle penetrating the endometrium from the myometrium was identified. On SHG, a polyp was suspected when a focal polypoid lesion was seen within the endometrial cavity. All patients underwent hysteroscopy and endometrial biopsy, the findings of which were used as the criterion standard. Sensitivity and specificity for TVCD and SHG were calculated and compared by the McNemar test. RESULTS: Hysteroscopy and endometrial biopsy findings were as follows: endometrial polyps, 41; endometrial hyperplasia, 3; cystic atrophy, 4; proliferative endometrium, 2; and endometritis, 1. Sensitivity and specificity for TVCD and SHG were 95% and 80% and 100% and 80%, respectively (McNemar test, P = .5) CONCLUSIONS: Transvaginal color Doppler sonography and SHG had similar performance for diagnosing endometrial polyps.  相似文献   
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