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Retention is a major part of orthodontic treatment, not an optional secondary protocol. In recent years, studies investigating dentofacial changes during and after the growth period have led most clinicians to use fixed retention appliances after treatment. Fixed retainers can be attached to the teeth directly or indirectly. We present a practical, indirect method for bonding fixed retainers, using Sondhi Rapid-set Indirect Bonding Adhesive (3M Unitek, Monrovia, Calif).  相似文献   
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Recombinant activated factor VII has been Food and Drug Administration approved to treat hemorrhages in hemophiliac patients with inhibitors and in acquired hemophilia patients. Recombinant activated factor VII use has also been considered for the management of uncontrolled bleeding in a number of congenital and acquired hemostatic abnormalities. The myeloproliferative disorders are a group of clonal hematologic diseases where, frequently, abnormal platelet function is considered a hallmark. This is the first case report addressing the clinical benefit of off-label use of recombinant activated factor VII in an attempt to control intractable bleeding in a patient with a myeloproliferative disorder after splenectomy.  相似文献   
34.

Background  

Different interventions can reduce the burden of the chronic low back pain. One example is the use of a 'Back School Programme'. This is a brief therapy that uses a health education method to empower participants through a procedure of assessment, education and skill development. This study aimed to evaluate to what extent the programme could improve quality of life in those who suffer from the condition.  相似文献   
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OBJECTIVE: This is an in vitro assessment of pH level and calcium ion release exhibited by 3 calcium hydroxide-based root canal sealers-Sealapex, Apexit, and Acroseal. STUDY DESIGN: The materials were prepared according to the manufacturers' instructions and placed in 1 cm long and 4 mm diameter tubes. The tubes were then immersed in a glass flask containing 10 mL bidistilled water (n = 15), which was sealed and stored at 37 degrees C before the materials had set. The control group contained bidistilled water with empty tubes (n = 12). At predetermined time intervals (24 h, 96 h, and 7, 15, and 28 days) the pH of the bidistilled water was tested with a pH meter and for released calcium by using spectrophotometry. The data were statistically analyzed using 1-way analysis of variance for the comparison of the materials at each time point. If the difference was significant, individual comparisons were performed by Tukey multiple comparisons test (alpha = .05). RESULTS: Sealapex produced higher pH and released significantly higher calcium amounts than the other 2 sealers at all periods (P < .05). Apexit showed higher calcium release than Acroseal at the end of 15 days (P < .05). There was no significant difference in the pH between Apexit and Acroseal (P > .05). CONCLUSION: The new Acroseal sealer presented the least calcium ion release and pH than Sealapex and less calcium ion release than Apexit sealer.  相似文献   
36.
BACKGROUND: Because the clinicopathologic effects of takhzeen al-qat are similar to those induced by smoking, the aim of this paper was to study the oral effect of 3 bad oral habits: takhzeen al-qat and cigarette and water-pipe smoking. STUDY DESIGN: This study was done on 33 Yemeni chronic qat users grouped as heavy cigarette smokers (GI), nonsmokers (GII) and water-pipe smokers (GIII). In all cases (n = 33) 2 biopsies were taken (n = 66), one from the buccal mucosa at the chewing side and the other from a similar mucosa at the contralateral (nonexposed) side. Biopsies were prepared for routine H&E staining. RESULTS: Acanthosis appeared in 88% and 0%, abnormal rete ridges in 70% and 3%, hyperparakeratosis in 67% and 0%, and epithelial dysplasia in 30% and 0% of the chewing and nonchewing sides, respectively, in the 3 groups. Epithelial dysplasia appeared in 41% of GI and GIII (smokers) but in only 9% of GII (nonsmokers). CONCLUSIONS: Takhzeen al-qat causes distinct histopathologic changes in the oral mucosa at the side of chewing, such as acanthosis, abnormal rete ridges, and hyperparakeratosis. The association between takhzeen al-qat and cigarette or water-pipe smoking may increase the risk of epithelial dysplasia.  相似文献   
37.
Three-point Dixon techniques achieve good lipid-water separation by estimating the phase due to field inhomogeneities. Recently it was demonstrated that the combination of an iterative algorithm (iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL)) with a fast spin-echo (FSE) three-point Dixon method yielded robust lipid-water decomposition. As an alternative to FSE, the gradient- and spin-echo (GRASE) technique has been developed for efficient data collection. In this work we present a method for lipid-water separation by combining IDEAL with the GRASE technique. An approach to correct for errors in the lipid-water decomposition caused by phase distortions due to the switching of the readout gradient polarities inherent to GRASE is presented. The IDEAL-GRASE technique is demonstrated in phantoms and in vivo for various applications, including pelvic, musculoskeletal, and (breath-hold) cardiac imaging.  相似文献   
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The aim of this study is to identify the effect of time and pressure of tourniquet in blood pressure and pulse rate immediately after the releasing of tourniquet in the upper and lower extremity of the orthopedic surgeries. This retrospective study examined 206 consecutive patients. Comparisons of the systolic and diastolic pressure and heart rate were made before the induction of anesthesia and tourniquet inflation, and immediately after the deflation. In general, there was no significant difference in hemodynamic changes between the upper- and lower-limb with regard to the type of anesthesia. There was no significant correlation between systolic blood pressure and tourniquet pressure, while by increasing the tourniquet time significantly, the systolic blood pressure decreases immediately after the deflation. Interestingly, the considerable increase in age paralleled with a significant decrease in the systolic blood pressure. The effect of tourniquet time is more than the age. There was no significant correlation between the tourniquet pressure and tourniquet time with diastolic blood pressure. Simply the increase in age significantly paralleled with the mild decrease in diastolic blood pressure Orthopedic surgeons are recommended not to rely on the benefits of tourniquet to raise blood pressure due to hypotensive conditions after the deflation especially in the old.  相似文献   
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