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991.
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Abstract – The prognosis of tooth replantation is usually related to the need of endodontic treatment, which has a direct relationship with the occurrence of root resorptions. Several studies have been undertaken in an attempt to prevent, delay, or treat these complications, which are the main causes of loss of replanted teeth. This literature review examines research evidence on intracanal dressings and root canal filling materials used in cases of tooth replantation. A comprehensive search was performed in the Medline/Pubmed, Bireme and Scielo full‐text electronic journal databases to retrieve English‐language articles referring to these topics that had been published between 1964 and 2010. Calcium hydroxide (CH) remains the usually recommended choice as an intracanal medicament in replanted teeth; however, there is evidence to support the initial use of a corticosteroid‐antibiotic combination such as Ledermix paste to control potential early resorption, prior to the introduction of CH where the beneficial effect in the treatment of progressive root resorption has been well proven. Regarding root filling materials, CH‐containing sealers are a good option because of their biological properties. Accurate diagnosis and adequate treatment plan may constitute very complex tasks, particularly in tooth avulsion because several variables are involved. In addition to the technical knowledge and clinical experience directed toward the quality of treatment, patient education may favorably influence the survival of replanted teeth.  相似文献   
994.
Objective To estimate the relationship between Ni concentrations in the ambient air and in the urine, at a battery plant using nickel hydroxide. Methods Workers occupationally exposed to a mixture of nickel hydroxide, metallic cobalt and cobalt oxyhydroxide dust were studied during two consecutive workdays. Air levels of Ni and Co in total dust were determined by personal sampling in the breathing zone. Both metals in air were sampled by Teflon binder filters and analyzed by inductively coupled plasma absorption emission spectrophotometry. Urine was collected from 16 workers immediately before and after the work shift. Urinary Ni and Co concentrations were measured by electrothermal atomic absorption spectrometry. Results A poor correlation was seen between Co in the air and in post-shift urine (r = 0.491; P < 0.01), and no correlation was found between Ni in the air and in post-shift urine (r = 0.272; P = 0.15), probably due to the use of respiratory protection. The subjects were exposed to higher levels of Ni than Co (Ni (mg/m3) = −0.02 + 7.41 Co (mg/m3), r = 0.979, P < 0.0001). Thus, exposure to Co at 0.1 mg/m3 should produce a Ni level of 0.7 mg/m3. According to section XIII of the German list of MAK and BAT Values, a relationship between exposure to Co and urinary Co excretion, Co (μg/l) = 600 Co (mg/m3), has been established and the relationship between soluble or insoluble Ni salts in the air and Ni in urine was as follows: Ni (μg/l) = 10 + 600 Ni (mg/m3) or Ni (μg/l) = 7.5 + 75 Ni (mg/m3). Assuming nickel hydroxide to be soluble and to be insoluble, the Ni concentrations corresponding to Ni exposure at 0.7 mg/m3 were calculated as 430 and 60 μg Ni/l, respectively. Similarly, exposure to Co at 0.1 mg/m3 should result in Co urinary concentrations of 60 μg Co/l. On the other hand, a good correlation was found between Co and Ni in post-shift urine (Ni (μg/l) = 9.9 + 0.343 Co (μg/l), r = 0.833, P < 0.0001). On the basis of this relationship, the corresponding value found in our study was 0.343 × 60 μg Co/l + 9.9 = 30.5 μg Ni/l. This value was close to that calculated by the equation for a group of insoluble compounds, but about 14 times lower than that calculated by the equation for a group of soluble compounds. Conclusions Our results suggest that exposure to nickel hydroxide yields lower urine nickel concentrations than the very soluble nickel salts, and that the grouping of nickel hydroxide might be reevaluated. Therefore, to evaluate conclusively the relationship between nickel hydroxide dust in the air and Ni in post-shift urine, further studies are necessary.  相似文献   
995.
Lemierre's syndrome: Porphyromonas asaccharolytica as a putative pathogen   总被引:1,自引:0,他引:1  
A case of Lemierre's syndrome is reported in which metastatic abscesses resulted from septic thrombophlebitis of the internal jugular vein secondary to bacterial pharyngitis. A 32-year-old male suffering from a painful left-sided neck mass, sore throat, and fever was admitted to our hospital. Computed tomography revealed thrombosis of the left internal jugular vein, septic pulmonary emboli, and a liver abscess. Blood culture showed Porphyromonas asaccharolytica. Although empyema occurred transiently during the treatment, the patient recovered following prolonged antimicrobial therapy. Although Fusobacterium species are a well-known cause of Lemierre's syndrome, cases in whom Porphyromonas species was isolated have scarcely been reported. Moreover, case reports from Japan have been few.  相似文献   
996.
Background: Although there are several factors which may contribute to oxidative stress at high altitude, little is known about the association between oxidative stress and aging in the community‐dwelling elderly in the Tibetan Plateau. Methods: Reactive oxygen species (ROS) and comprehensive geriatric functions were examined among 235 community‐dwelling elderly subjects aged 60 years or more (146 Hans and 89 Tibetans). As a marker of ROS, the levels of reactive oxygen metabolites (ROM) were measured using the d‐ROM test. Results: The rate of dependence of basic activities of daily living (basic ADL) among Tibetan elderly highlanders was significantly higher than that among Han elderly highlanders. The d‐ROM level was higher among the Tibetan elderly than those among the Han elderly (Tibetan 465.6 ± 97.9 Carr U, Han 415.3 ± 72.0 Carr U, P = 0.003). The ROM level was higher among women than those among men. Stepwise multiple regression analysis showed that being Tibetan, female, and oxygen saturation were independent predictors of increasing d‐ROM level (Tibetan β, 0.241; female β, 0.206; oxygen saturation β, 0.218). The high levels of ROM (d‐ROM >500 Carr U) were significantly associated with dependence of basic ADL after adjustment for age, sex and ethnicity (odds ratio = 2.51, P = 0.028). Conclusion: The findings of this study imply the possibility that ROS is higher among Tibetan elderly highlanders than that of Han, which related to the geriatric items. Further studies are needed to show the impact of oxidative stress on the aging of highlanders.  相似文献   
997.
Intentional reimplantation is defined as a procedure in which an intentional tooth extraction is performed followed by reinsertion of the extracted tooth into its own alveolus. In this paper, intentional reimplantation is described and discussed as a treatment approach to root canal instrument separation in conjunction with root perforation. An 8-year follow-up case report is presented. The reimplanted tooth is now a fixed bridge abutment. Although successful in this case, the intentional reimplantation procedure should be considered a treatment of last resort, that is, when another treatment option is not viable for the treatment of root perforation/instrument retrieval.  相似文献   
998.
BACKGROUND AND PURPOSE:3D turbo field echo with diffusion-sensitized driven-equilibrium preparation is a non–echo-planar technique for DWI, which enables high-resolution DWI without field inhomogeneity–related image distortion. The purpose of this study was to evaluate the feasibility of diffusion-sensitized driven-equilibrium turbo field echo in evaluating diffusivity in the normal pituitary gland.MATERIALS AND METHODS:First, validation of diffusion-sensitized driven-equilibrium turbo field echo was attempted by comparing it with echo-planar DWI. Five healthy volunteers were imaged by using diffusion-sensitized driven-equilibrium turbo field echo and echo-planar DWI. The imaging voxel size was 1.5 × 1.5 × 1.5 mm3 for diffusion-sensitized driven-equilibrium turbo field echo and 1.5 × 1.9 × 3.0 mm3 for echo-planar DWI. ADCs measured by the 2 methods in 15 regions of interests (6 in gray matter and 9 in white matter) were compared by using the Pearson correlation coefficient. The ADC in the pituitary anterior lobe was then measured in 10 volunteers by using diffusion-sensitized driven-equilibrium turbo field echo, and the results were compared with those in the pons and vermis by using a paired t test.RESULTS:The ADCs from the 2 methods showed a strong correlation (r = 0.79; P < .0001), confirming the accuracy of the ADC measurement with the diffusion-sensitized driven-equilibrium sequence. The ADCs in the normal pituitary gland were 1.37 ± 0.13 × 10−3 mm2/s, which were significantly higher than those in the pons (1.01 ± 0.24 × 10−3 mm2/s) and the vermis (0.89 ± 0.25 × 10−3 mm2/s, P < .01).CONCLUSIONS:We demonstrated that diffusion-sensitized driven-equilibrium turbo field echo is feasible in assessing ADC in the pituitary gland.

DWI is widely used to diagnose cerebrovascular diseases, intracranial tumors, and inflammation.110 However, it is difficult to evaluate skull base structures by the most common imaging technique used with echo-planar (EP)-DWI. Previous studies have revealed the efficacy of DWI for skull base tumors such as pituitary adenoma; however, they are mostly limited to macroadenomas large enough to calculate the ADC by using EP sequences.37 Compared with EP-DWI, 3D diffusion-sensitized driven-equilibrium turbo field echo (DSDE-TFE) obtained DWI has higher spatial resolution and fewer susceptibility artifacts.11 To our knowledge, to date, the diffusivity of the normal pituitary gland has not been fully evaluated, especially in those glands surrounded by aerated sphenoid sinuses. Therefore, the purpose of this study was to evaluate the feasibility of DSDE-TFE in evaluating diffusivity in the normal pituitary gland.  相似文献   
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