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41.
Progressive diaphyseal dysplasia (PDD), a rare disorder of bones, in recent years has been accepted as a systemic disease within the spectrum of connective tissue disorders associated with immunological abnormalities. Steroids have been used in the treatment of PDD with variable success. In this report PDD is described in a 5-year-old boy who presented with leg pain, fatigue, headache and anorexia with an onset in infancy. Physical examination revealed a waddling gait, thorax deformity and thickening in the upper extremities. The diagnosis was made by radiologic demonstration of cortical thickening and a narrowed medullary cavity of the long bones of extremities. Bone scintigraphy showed areas of increased osteoblastic activity in the diaphyseal part of the long bones of extremities and the skull. Electron microscopic examination revealed myopathic and vascular changes. Serum immunoglobulin A, G and M levels were elevated and CD4 positive T cell numbers were low. Deflazacort, a steroid with a similar anti-inflammatory effect to prednisolone but with fewer adverse effects, was started in a dose of 1.2 mg/kg/day. Deflazacort treatment resulted in clinical and radiological improvement within 12 months with no side effects. In conclusion, steroids may be recommended as an effective method of treatment in PDD and deflazacort may be a safe alternative steroid.  相似文献   
42.
Background Patients with Turner syndrome (TS) are treated with GH to increase adult height. Although it is well established that GH promotes longitudinal bone growth, the effects of GH treatment on bone density are less clear. Objective To determine how GH treatment affects trabecular bone mineral density (BMD) in girls with TS at prepubertal ages in a prospective multicentre study. Patients and method Twenty‐two patients with TS in the prepubertal period with a mean age of 9·8 ± 2·5 (range 3·6–12·8) years were included in the study. All girls with TS underwent measurement of areal BMD using dual‐energy X‐ray absorptiometry (DXA) to obtain pretreatment anteroposterior (AP) lumbar spine values at L1–L4. Patients received GH (Genotropin) subcutaneously for 1 year at a dose of 0·05 mg/kg/day. Height and weight were measured at 3‐monthly intervals. The AP lumbar spine areal BMD was remeasured using the same technique after 1 year of treatment. Lumbar spine BMD Z‐scores and volumetric BMD (vBMD) Z‐scores were calculated using national standards. Results The height SDS of our cases showed a significant increase with GH therapy. The pretreatment lumbar spine (L1–L4) BMD Z‐score was –1·2 ± 1·2 SD and the vBMD Z‐score was –0·8 ± 1·6 SD. There were no significant changes in these values after 1 year of GH treatment. Prepubertal TS girls more than 11 years of age had lower vBMD Z‐scores (–1·7 ± 1·7 SD) than the girls aged less than 11 (–0·1 ± 1·0 SD) (P < 0·05) at the onset of therapy. No significant changes were observed in these values after 1 year of GH therapy. Conclusions Osteopaenia becomes apparent in prepubertal TS patients as they reach pubertal age. BMD evaluation may be necessary in these prepubertal TS girls at diagnosis. Short‐term GH therapy in these TS patients does not have a significant effect on bone density when measured at a site with a predominance of trabecular bone.  相似文献   
43.
Freiberg’s disease usually affects the second and, less commonly, the third metatarsal heads [Helal and Gibb in Foot Ankle 8(2):94–102, 1987]. It was mainly observed unilaterally in adolescent females (F/M: 3/1–4/1) (Hay and Smith in The Foot 2:176–178, 1992). Bilateral occurrence and adjacent metatarsal involvement has been previously reported separately [Maresca et al. in Arthroscopy 12(1):103–108, 1996; Rafee et al. in Foot Ankle Surg 12:153–155, 2006]. The cases presented here involve two female patients aged 42 and 72 with bilateral Freiberg’s disease in both the second and third metatarsal heads. To our knowledge, this is the first report of such involvement of both the second and third metatarsal heads.  相似文献   
44.
The aims of this study were to develop a three-dimensional (3D) mathematical model of a typical root resorption crater and to correlate two-dimensional (2D) surface area measurements to 3D volumetric measurements of root resorption craters created under light and heavy orthodontic forces. Data were obtained from a previous study of 36 first premolars from 16 subjects requiring extraction of these teeth as part of their orthodontic treatment. Buccal tipping forces of 25 or 225 g were applied for an experimental period of 28 days. After extraction, the samples were prepared for scanning electron microscopy (SEM) imaging, image processing and analysis. Surface area (2D) and volumetric (3D) measurements of all craters were obtained. A mathematical analysis of the 2D/3D relationship enabled the determination of an appropriate digital model for the shape, type and dimensions of resorption craters, which was also able to distinguish between a 'hemispheric' model versus a 'layered' model of craters.The results demonstrated that 2D and 3D measurements were strongly correlated (r = 0.991**). Within the light and heavy force groups, the measurements were also strongly correlated (r = 0.978** and r = 0.994**, respectively). For a 28 day experimental period, 2D measurements of root resorption craters were found to be as reliable as 3D measurements.  相似文献   
45.
PURPOSE: The purpose of this study was to evaluate the effects of extraction therapy and use or nonuse of headgear on the soft tissue profile in subjects with different growth patterns. METHODS: A total of 41 subjects were included in the study. The patients were treated with standard edgewise mechanics and had 4 first premolars extracted. The type of growth pattern was assessed as mesiodivergent or hyperdivergent. The results were analyzed by 2-way analysis of variance. RESULTS: When comparing the mean changes between growth pattern types, the vertical changes in Sn and A' were found to be statistically significant (P<.05). The vertical change in A' was also found to be significant between the headgear use and nonuse groups (P<.05). Interaction was found to be significant for Steiner upper and lower lip values and the vertical change in A. The upper and lower lips were retracted significantly more by headgear use in patients with hyperdivergent growth pattern (P<.05). CONCLUSIONS: The results of this study indicate that the use of headgear should be avoided in hyperdivergent patients. The avoidance of premolar extraction, based on the possibility of a significant detrimental effect on the facial profile, is not justified.  相似文献   
46.
47.
This article investigated the possible neurotoxic effect of sulfite in normal and sulfite oxidase (SOX) deficients rats by evaluating EEG spectral analysis. Rats were divided into four groups: control (C), sulfite treated (25 mg/kg) (ST), SOX deficient (SD), and sulfite treated SOX deficient (STSD) groups. The qEEG spectral analyses of two spectral parameters including power and relative power were performed. The mean power of SD group was found to be increased compared to the all other groups and returned to control levels after sulfite administration. The power of the four frequency bands (delta, theta, alpha, beta) of the SD group corresponds to the mean power. EEG relative power increased in the delta band with concomitant decreases in power measured in the alpha frequency range. It was concluded that exogenous administration of sulfite affected the brain electrical activity in SOX deficiency, and improved neuroprotection.  相似文献   
48.
It has been recognized that nasal airway resistance (NAR) is elevated in patients with OSA. However, little is known regarding the influence of nasal resistance on mandibular advancement splint (MAS) treatment outcome in OSA patient. We hypothesized that nasal resistance differs between MAS responders and nonresponders and therefore may influence treatment outcome. Thirty-eight patients with known OSA underwent polysomnography while wearing a custom-made MAS. Treatment outcome was defined as follows: Responders (R) > or =50% reduction in AHI, and Nonresponders (NR) as <50% reduction in AHI. NAR was measured using posterior rhinomanometry in both sitting and supine positions, with and without MAS. The mean AHI in 26 responders was significantly reduced from 29.0 +/- 2.9/h to 6.7 +/- 1.2/h; P < 0.01). In 12 nonresponders there was no significant change in AHI (23.9 +/- 3.0/h vs 22.0 +/- 4.3/h; P=ns). Baseline NAR was significantly lower in responders in the sitting position compared to nonresponders (6.5 +/- 0.5 vs 9.4 +/- 1.0 cm H2O; P < 0.01). There was no significant change in NAR (from baseline) with MAS in either response group while in the sitting position, but in the supine position NAR increased significantly with MAS in the nonresponder group (11.8 +/- 1.5 vs. 13.8 +/- 1.6 cm H2O/L/s; P < 0.01). Logistic regression analysis revealed that NAR and BMI were the most important predictive factors for MAS treatment outcome. These data suggest that higher levels of NAR may negatively impact on treatment outcome with MAS.  相似文献   
49.
Recent publications suggest the utility of temozolomide (TMZ) in the management of aggressive pituitary adenomas and carcinomas, resistant to conventional treatments. The response to TMZ is inversely correlated with tumoral expression of O-6 methylguanine DNA methyl transferase (MGMT). Therefore, we aimed to assess MGMT immunoexpression in pure GH-secreting pituitary adenomas, in an effort to predict the likelihood of response to TMZ, and to correlate MGMT immunoexpression with Ki-67 LI and cytokeratin (CK) distribution pattern. Our material consisted of 36 GH-secreting pituitary adenomas (21 female,15 male, mean age 42.5±10.5), operated at our center between 2003 and 2010. Immunostaining for MGMT, Ki-67, and CK was performed using avidin-biotin-peroxidase complex method. Immunoreactivity for MGMT and Ki-67 was evaluated microscopically and recorded as percentages of positive nuclear immunostaining. CK distribution pattern was also evaluated microscopically and assoreted into dot-like and nondot-like pattern subtypes. MGMT immunoexpression scored as 0=none, 1=<10%, 2=<25%, 3=<50%, and 4=>50%. Staining for MGMT was <10% (score 1) in 30 (83.3%), 10-25% (score 2) in 3 (8.3%), 25-50% (score 3) in 2 (5.6%) and >50% (score 4) in 1 (2.8%) of the tumors, respectively. There was no correlation between Ki-67 LI and CK distribution pattern with MGMT immunoreactivity (P>0.05). Data from the current study suggest a large proportion of GH-secreting adenomas, including those with dot-like CK distribution pattern and high Ki-67 LI, demonstrate negative/low MGMT immunoreactivity and could be treated with TMZ, if conventional treatment fails.  相似文献   
50.
The aim of the study was to investigate antioxidant activities of Ganoderma lucidum and Funalia trogii. Ethanol and water crude extracts from G. lucidum and F. trogii were investigated for their antioxidant capacity in some different assays, namely, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, metal chelating activity against ferrous ions, and plasma lipid peroxidation inhibitory. In addition, the amounts of total phenol, ascorbic acid, β-carotene, and lycopene components in the extracts were determined. Among the four mushroom extracts, G. lucidum water extract and G. lucidum ethanol extract showed the highest scavenging activity against DPPH radicals (50% inhibitory concentration?=?0.055?±?0.001?mg/mL). Total phenol was the major antioxidant component found in the mushroom extracts. These results showed that G. lucidum may be used in pharmaceutical applications because of its effective antioxidant properties.  相似文献   
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