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1.
<正>作者回顾性分析了2 181例人工全髋、膝关节置换术患者资料,对于部分感染高风险患者延长7 d预防性口服抗生素,分析90 d感染率。结果发现,人工膝关节和人工髋关节90 d感染率分别为1. 0%和2. 2%。高风险未使用延长口服抗生素组90 d感染率为使用延长口服抗生素组4. 9和4. 0倍。因此作者认为,延长口服抗生素可以显著降低高  相似文献   
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PURPOSE: To explore whether there is a difference in the perceived height and actual height in the perimenopausal or menopausal woman and discover the difference's effect on osteoporosis health-seeking preventive behaviors and risk factor awareness. DATA SOURCES: Sixty-three perimenopausal and menopausal women, aged 45-70 years, who presented at three Midwestern clinics for their annual physical exam. Data were collected with The Osteoporosis Questionnaire, which included the Osteoporosis Risk Questionnaire, Health-O-Meter height measuring stick, tape measure with inch-rule for arm span measurements, and balance scale for weight. CONCLUSIONS: There were a significant relationship between actual height loss and osteoporosis risk factors (r = 0.41595, p = 0.0007) and a trend for a relationship between adjusted height loss and osteoporosis risk factors (r = 0.2407, p = 0.0574). IMPLICATIONS FOR PRACTICE: Due to the great expense of current testing for bone mass density loss, the results of this study may help clinicians more readily identify markers for increased risk of osteoporosis through simple height measurements and osteoporosis risk factor assessments during annual visits.  相似文献   
3.
To study the self-consciousness of children with learning disabilities (LD) and to identify related factors. Methods Five hundred and sixty pupils graded from 1 to 6 in an elementary school were investigated. According to the pupil rating scale revised screening for learning disabilities (PRS), combined Raven‘s test (CRT) and achievement of main courses, 35 of 560 pupils were diagnosed as LD children. Thirty-five children were selected from the average children and 35 from advanced children in academic achievement equally matched in class, gender, and age with LD children as control groups. The three groups were tested by Piers-Harris children‘s self-concept scale. Basic information of each subject was collected by self-made questionnaire. Results Compared with the average and advanced children, LD children got significantly lower scores in self-concept scale. Based on logistic regression analysis, 3 factors were identified, including family income per month, single child and delivery model. Conclusion The results suggest that self-consciousness of children with LD is lower than that of normal children.  相似文献   
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AIM: To record the cytotoxicity of Resilon and Epiphany (Pentron clinical technologies, Wallingford, CT, USA) using a root model. METHODOLOGY: Thirty teeth with single roots were sectioned at the enamel-cementum junction, the root canals prepared and each root then sterilized before filling with the lateral condensation technique using one of three filling materials (n = 10 per group): Resilon and Epiphany, Sealite (Septodont, Pierre Rolland, Merignac, France) and gutta-percha, Roekoseal Automix (Coltène/Whaledent, Langenau, Germany) and gutta-percha. The roots were stored at 37 degrees C in an incubator to allow for setting of the root filling materials. The apices of the roots were dipped in 1 mL of MEM culture medium for 1, 2, 7 and 30 days renewing the medium every day. After 24 h contact between the medium and the filled roots, the medium was used to measure the cytotoxicity on mouse fibroblasts L 929 with the MTT assay that recorded the mitochondrial activity of the target cells. An additional test according to ISO 10993-5 standards was undertaken to compare Resilon and Epiphany. RESULTS: The root model showed no statistically significant differences between the sealers at 7 and 30 days (NS). Epiphany and Resilon were the most cytotoxic materials at 1 and 2 days (P < 0.001). Unlike Epiphany, Resilon was not cytotoxic when tested according to ISO 10993-5 standards. CONCLUSIONS: The cytotoxicity of Resilon + Epiphany, due mainly to Epiphany, decreased after 2 days to reach a level comparable with commonly used root canal sealers.  相似文献   
6.
Abstract:  Aims:  A single-centre, randomized single-blind parallel study was undertaken to compare staining seen with three brushing regimens and to determine subject perception of side effects such as staining and effects on taste. Methods:  This 6-week parallel study used 157 volunteers who were randomized into one of three treatment groups: (i) brushing in the morning and evening with a normal dose of a 1% chlorhexidine gel, (ii) brushing with a low dose of chlorhexidine gel in the evening and a whitening dentifrice in the morning, and (iii) brushing with a standard fluoride paste in the morning and evening. Following home usage of their allocated products, the study volunteers returned after 3 and 6 weeks to record the amount of stain present. After the 6-week period, subject perception of taste and stain acceptability was determined using a questionnaire. Results:  After 6 weeks of use of the low-dose chlorhexidine gel and whitening dentifrice, significantly more stain was seen compared with the use of a standard dentifrice ( P  < 0.0001). Similarly, significantly more stain was seen with use of the normal-dose chlorhexidine gel compared with the low-dose gel and whitening dentifrice ( P  = 0.0007). Approximately 30% of individuals on the low-dose chlorhexidine gel regimen found the amount of stain unacceptable and 10% noted an effect on their taste perception. Conclusions:  The use of low dose of chlorhexidine gel at night and a whitening paste in the morning produced a significant amount of stain that 30% of subjects considered unacceptable.  相似文献   
7.
This study tested the hypothesis that newly triturated amalgam condensed vertically on old amalgam was essential for establishing a bond between the new and old amalgams. Twelve rectangular bars were prepared with Dispersalloy and Tytin to establish their baseline flexure strength values. An additional 12 specimens were made and separated into 24 equal halves. All fracture surfaces were abraded with a flat end fissure bur. Twelve surfaces were paired with the original amalgam, and the remaining 12 surfaces were repaired with a different amalgam. At first, freshly triturated amalgam was condensed vertically on the floor of the specimen mold (Group A). The majority of specimens repaired with Group A failed to establish bond at the repair interface. All repair surfaces were abraded again and prepared by a second method. A metal spacer was used to create a four-wall cavity to facilitate vertical condensation directly on the repair surface (Group B). The specimens were stored in ambient air for seven days prior to flexure testing. The strength of specimens repaired with Group B ranged from 26% to 54% of the baseline specimens. ANOVA showed that amalgams repaired with a different amalgam yielded higher strength values than those repaired with the original amalgam, and the baseline specimens exhibited significantly higher strength values than all the repaired specimens.  相似文献   
8.
We investigated the clinical and histopathologic features of 26 cases of mucocele of the glands of Blandin-Nuhn. There was a female predominance, and most patients were younger than 20 years. Fifteen patients first visited a medical doctor and 9 visited a dentist before being referred to our department. The average duration from the time the lesion was first noticed to the patient's visit was 3.6 months. All lesions were located on the ventral surface of the tongue. In 17 patients, mucoceles were seen at the tip of the tongue, whereas 9 lesions occurred more posteriorly. Lesions were situated at the midline in 19 patients and laterally in 7 patients. All lesions presented as an exophytic mass, often with a polypoid appearance. All mucoceles were histopathologically of the extravasation type, suggesting that trauma may represent a frequent initiating factor.  相似文献   
9.
Human acquired enamel pellicle is formed by molecules selectively adsorbed onto tooth surfaces. The present work describes the use of monoclonal antibody (mAb) technology as a novel approach to identify micro amounts of components present in pellicle. MAbs were obtained with reactivities against statherin, histatin, mucous glycoprotein 1(MGI), albumin, amylase and human immunoglobulins (Igs), indicating that these are pellicle components, which was further confirmed by immunoblotting. No mAbs against proline-rich proteins (PRPs), lysozyme, mucous glycoprotein 2 (MG2), carbonic anhydrase, lactoferrin or peroxidase were obtained, suggesting that these components are absent, present in low amounts, or exhibit low antigenicity. Further characterization of the binding epitopes of some of th e obtained anti-MGO, anti-statherin and anti-histatin mAbs were carried out and the biological relevance is discussed. The results open up the possibility that immunization with human pellicle and mAbs production can be employed to identify hitherto unknown constituents of pellicle.  相似文献   
10.
Durable clenching on a particular occlusal area may affect the masticatory muscle activity and induce transitional deformation of the dentoalveolar, mandibular and temporomandibular tissues. These effects may provide detectable alterations in the occlusal contact pattern. The aim of this study was to evaluate the subsequent effect of clenching on the number and location of occlusal contacts. This study was carried out on 16 volunteers with correct occlusion and sharply demarcated occlusal contact pattern. The patient closed to intercuspal position with maximal biting force and the occlusal contacts were revealed with a 12 microns thick occlusal foil. Then a gnathometer was placed between the upper and lower incisors and the mouth was closed for two minutes with about 50 N closing force. After that the occlusal contacts were evaluated again. Paired t-test was used to evaluate the data. Both before and after clenching the highest average number of contacts was recorded on the surface of first molars. They were followed in decreasing order by the second molars, second premolars, first premolars, and finally the canines. When the number of contacts was compared in tooth groups, the first molars and the second premolars had more contacts than the second molars and the first premolars. On the surfaces of molars more occlusal contacts were registered after clenching than before. Significant differences were found in case of the left second molar only. It was concluded that durable clenching on a particular occlusal area might change transitionally the distribution of occlusal contacts.  相似文献   
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