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Elizabeth S Hart Marilyn H Kelly Beth Brillante Clara C Chen Navid Ziran Janice S Lee Penelope Feuillan Arabella I Leet Harvey Kushner Pamela G Robey Michael T Collins 《Journal of bone and mineral research》2007,22(9):1468-1474
Most lesions in FD and their attendant functional disability occur within the first decade; 90% of lesions are present by 15 years, and the median age when assistive devices are needed is 7 years. These findings have implications for prognosis and determining the timing and type of therapy. INTRODUCTION: Fibrous dysplasia of bone (FD) is an uncommon skeletal disorder in which normal bone is replaced by abnormal fibro-osseous tissue. Variable amounts of skeletal involvement and disability occur. The age at which lesions are established, the pace at which the disease progresses, if (or when) the disease plateaus, and how these parameters relate to the onset of disability are unknown. To answer these questions, we performed a retrospective analysis of a group of subjects with FD. MATERIALS AND METHODS: One hundred nine subjects with a spectrum of FD were studied for up to 32 years. Disease progression was assessed in serial (99)Tc-MDP bone scans by determining the location and extent of FD lesions using a validated bone scan scoring tool. Physical function and the need for ambulatory aids were assessed. RESULTS: Ninety percent of the total body disease skeletal burden was established by age 15. Disease was established in a region-specific pattern; in the craniofacial region, 90% of the lesions were present by 3.4 yr, in the extremities, 90% were present by 13.7 yr, and in the axial skeleton, 90% were present by 15.5 yr. Twenty-five of 103 subjects eventually needed ambulatory aids. The median age at which assistance was needed was 7 yr (range, 1-43 yr). The median bone scan score for subjects needing assistance was 64.3 (range, 18.6-75) compared with 23.1 (range, 0.5-63.5) in the unassisted subjects (p < 0.0001). Among subjects needing assistance with ambulation, 92% showed this need by 17 yr. CONCLUSIONS: The majority of skeletal lesions and the associated functional disability occur within the first decade of life. The implication is that the window of time for preventative therapies is narrow. Likewise, therapeutic interventions must be tailored to where the patient is in the natural history of the disease (i.e., progressive disease [young] versus established disease [older subjects]). These findings have implications for prognosis, the timing and type of therapy, and the development of trials of new therapies and their interpretation. 相似文献
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Joao Colaco Vitor Goncalves Catarina Pinto Clara Castro Agueda Vieira Helio Retto 《Gynecological surgery》2007,4(3):223-224
New techniques of sling placement may be associated with infectious complications. Slings through the obturator foramen and
thigh can lead to a significant abscess formation within the thigh adductor muscles. A large thigh abscess associated with
a transobturator sling was diagnosed and treated. The authors report the evaluation and treatment of a unique infectious complication
of transobturator slings. 相似文献
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Summary It has been suggested that age changes in the morphology of the neuromuscular junction (NMJ) may reflect altered physical activity levels rather than the unique effects of ageing. Additionally, previous studies have indicated that the structure of the NMJ may be modulated with exercise. To investigate these questions, quantitative morphometry was determined on soleus and extensor digitorum longus (EDL) nerve terminals stained with zinc iodide-osmium from C57BL/6NNia mice under control and endurance exercised conditions at 12, 18 and 24 months of age.As previously observed, the area, perimeter, extent length and branch number of nerve terminals increased with age in both soleus and EDL. The changes were similar between the muscle types, although the changes were more pronounced in the phasic EDL. In 12-month-old animals, 2 months of endurance exercise resulted in significantly larger nerve terminals in both soleus and EDL, suggesting a functional adaptation. Exercised 18- and 24-month-old nerve terminals were smaller than corresponding controls, which indicated that exercise minimized or prevented further age-related nerve terminal elaboration. At all ages the exercised nerve terminals comprised a more homogeneous population than corresponding controls, which indicates that uniform physical activity can modulate NMJ morphometry. The magnitude of the changes suggests that subtle alterations in normal cage activity with advancing age do not have a significant effect on the morphology of nerve terminals. However, the morphology of the NMJ does change significantly in response to physical exercise training. 相似文献
6.
Hanbing Lu Clara A Scholl Yantao Zuo Elliot A Stein Yihong Yang 《Magnetic resonance in medicine》2007,58(3):616-621
In cerebral blood volume (CBV)-weighted functional MRI (fMRI) employing superparamagnetic contrast agent, iron dose and blood oxygenation level dependent (BOLD) contamination are two important issues for experimental design and CBV quantification. Both BOLD and CBV-weighted fMRI are based upon the susceptibility effect, to which spin-echo and gradient-echo sequences have different sensitivities. In the present study, CBV-weighted fMRI was conducted using spin-echo and gradient-echo sequences at 9.4T by systematically changing the doses of contrast agent. Results suggest that BOLD contamination is a significant component in CBV-weighted fMRI at high field, particularly when relatively low dose of contrast agent is administered. A mathematical model was developed to quantify the extravascular (EV) BOLD effect. With a TE of 35 ms, the EV BOLD effect was estimated to account for 76+/-12% of the observed spin-echo fMRI signal at 9.4T. These data suggest that correcting BOLD effect may be necessary for accurately quantifying activation-induced CBV changes at high field. 相似文献
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目的通过对甘肃农产区居民的饮食习惯、营养知识和态度的调查,从需方的角度对开展面粉营养素强化的可行性进行探讨。方法采用定性和定量调查相结合的方法,对4个地区的城市和农村的男性和女性分别进行现状和原因的调查分析。结果被调查地区多数城市(92.7%)和农村(60.7%)家庭日常饮食以面食为主,94.7%的城市家庭购买面粉,而在农村地区,多数家庭自己种植或购买小麦。城市居民较农村对营养和维生素有更多的了解和关注。农村男性对面粉营养素强化持怀疑态度,女性更加关注孩子的营养,认为目前的饮食单一,孩子可能营养不足。结论与农村地区相比,城市地区的社会经济条件和知识基础较利于开展面粉强化工作。 相似文献
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PURPOSE: Men have a lower uptake of genetic services than women; however, the specific needs and preferences of men at risk of genetic conditions other than hereditary breast ovarian cancer are not known. We ascertain the information preferences of men with a family history of prostate cancer. METHODS: Unaffected men and their partners were administered a written questionnaire. RESULTS: Responses were received from 280 men (response rate: 59.2%) and 174 partners (response rate: 74%). Most men (59.6%) reported having insufficient information about their risk and wanted further information about personal risk (93.2%) and risk management (93.6%). Strikingly, 56.3% preferred to receive information related only to positive outcomes. Urologists were the preferred source of information, but there was considerable interest in a multidisciplinary service approach significantly associated with the number of affected relatives (odds ratio = 1.94, P < .002). Partners' level of concern was not associated with interest in multidisciplinary services, satisfaction with information, or support received. CONCLUSIONS: Delivering services to men at risk will require a multifaceted approach by primary care providers and specialists. Challenges include meeting men's expectations in the face of uncertain medical knowledge, engaging those at high risk in multidisciplinary services, and delivering tailored information to those at lower risk. 相似文献
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During the early stages of nerve implantation, we followed the dynamic properties of the lateral gastrocnemius muscle of the rat, reinnervated with an acutely or chronically severed peroneal nerve. The aim of this study was to ascertain whether (1) the better functional recovery of a muscle reinnervated by a chronically severed foreign nerve is present from the onset of reinnervation, and (2) whether such functional improvement is due to the conditioning lesion effect. Our results indicate that better functional recovery is already apparent one week after nerve implantation, and it is due to the conditioning lesion effect, since tenotomy prevents such improvement. The tenotomy effect underlines the fact that some environmental factors concerning the target tissue, and not only the predegenerated nerve, are involved in the conditioning effect. © 1995 Wiley-Liss, Inc. 相似文献
10.
Ezio Martuscelli Clara Silvestre Maurizio Canetti Claudia de Lalla Anna Bonfatti Alberto Seves 《Macromolecular chemistry and physics.》1989,190(10):2615-2625
The crystallization and the thermal behaviour of thin films of isotactic polypropylene/hydrogenated oligo(cyclopentadiene) of low molecular weight (iPP/HOCP) are studied using optical microscopy and differential scanning calorimetry (DSC). The spherulite growth rate, the overall crystallization rate and the equilibrium melting temperature of iPP are decreased by the addition of HOCP to iPP. This leads to the hypothesis that iPP and HOCP form a miscible blend in the amorphous phase. This hypothesis is also supported by the detection of a single blend-composition-dependent glass transition temperature of each blend as determined by DSC. 相似文献