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991.
We compared the electroclinical features and evolution of patients with two different types of abnormal cortical organization: unilateral closed-lip schizencephaly (SCHZ) and unilateral polymicrogyria (PMG). Between February 1990 and June 2002, 51 children with either unilateral PMG or closed-lip SCHZ were selected through neuroradiological analysis for investigation at our service. We evaluated the frequency of epilepsy, electroclinical features and evolution. The mean time of follow-up was 7 years (range 1-12 years). All patients underwent neurological examination, computed tomography scan and magnetic resonance imaging, serial electroencephalographic (EEG) recordings and neuropsychological assessment. Thirty-six of the 51 patients had unilateral PMG. All patients had hemiparesis with mild spasticity. Mental retardation was mild in 20 and moderate in 14. In two patients IQ was normal. Partial motor seizures were recorded in 28 patients, with secondary generalization in 20. The median age at onset of seizures was 2 years (range 4 months-7 years). Interictal EEGs showed unilateral spikes in all patients. In 21 patients epilepsy worsened between the ages of 4 and 8 (mean 5.6 years) with frequent atonic seizures, atypical absences, epileptic negative myoclonus and gait difficulties. EEGs showed continuous spike-wave activity or bilateral high-frequency spike discharges during slow-wave sleep. Frequent relapses of atonic and myoclonic seizures were seen in nine patients. At present, 16 patients are seizure-free. Fifteen patients with unilateral SCHZ were included in the study. Focal motor seizures were registered in seven cases, in three of them with secondary generalization. The median age at onset of epilepsy was 2.5 years (range 1-4 years). Interictal EEGs showed unilateral spikes in these seven cases. All patients except one presented mild spastic hemiparesis. Mental retardation was mild in ten children, moderate in two and IQ was normal in three. Although the underlying mechanisms leading to PMG and SCHZ are probably similar, the electroclinical phenomenon of secondary bilateral synchrony with frequent negative myoclonus was not present in our cases with unilateral closed-lip SCHZ.  相似文献   
992.
The potential teratogenicity of antiepileptic drugs (AEDs) is a major concern for women with epilepsy who are considering pregnancy. Traditional AEDs are associated with an at least twofold risk of fetal malformations compared with the general population. The risk of malformations with newer AEDs is unclear. This article reports the multicenter clinical experience in Argentina of pregnant women with epilepsy receiving AEDs. Of 114 pregnancies monitored, 16 newborns had anomalies: 3 cardiac, 3 skull, and 2 gastrointestinal malformations, and 8 facial dysmorphies. Most fetal anomalies were observed following exposure to phenobarbital, valproate, and carbamazepine. Of 55 babies exposed to the new-generation AED oxcarbazepine (20 as combination therapy and 35 as monotherapy), one malformation (cardiac) was reported (in a patient receiving oxcarbazepine and phenobarbital). Thus, newer AEDs may have a lower teratogenic risk than traditional AEDs. These data add to the growing experience with AED therapy in pregnant women with epilepsy.  相似文献   
993.
The past two decades in the United States have seen a 24% rise in spontaneous late preterm delivery (34–36 weeks) of unknown etiology. This study tested the hypothesis that fetal growth was identical prior to spontaneous preterm (n = 221, median gestational age at birth 35.6 weeks) and term (n = 3706) birth among pregnancies followed longitudinally in Santiago, Chile. The hypothesis was not supported: Preterm‐delivered fetuses were significantly larger than their term‐delivered peers by mid‐second trimester in estimated fetal weight, head, limb, and abdominal dimensions, and they followed different growth trajectories. Piecewise regression assessed time‐specific differences in growth rates at 4‐week intervals from 16 weeks. Estimated fetal weight and abdominal circumference growth rates slowed at 20 weeks among the preterm‐delivered, only to match and/or exceed their term‐delivered peers at 24–28 weeks. After an abrupt growth rate decline at 28 weeks, fetuses delivered preterm did so at greater population‐specific sex and age‐adjusted birth weight percentiles than their peers from uncomplicated pregnancies (P < 0.01). Growth rates predicted birth timing: one standard score of estimated fetal weight increased the odds ratio for late preterm birth from 2.8 prior to 23 weeks, to 3.6 (95% confidence interval, 1.82–7.11, P < 0.05) between 23 and 27 weeks. After 27 weeks, increasing size was protective (OR: 0.56, 95% confidence interval, 0.38–0.82, P = 0.003). These data document, for the first time, a distinctive fetal growth pattern across gestation preceding spontaneous late preterm birth, identify the importance of mid‐gestation for alterations in fetal growth, and add perspective on human fetal biological variability. Am. J. Hum. Biol., 2009. © 2008 Wiley‐Liss, Inc.  相似文献   
994.
995.
996.
Loss of teeth is frequently associated with periodontal disease in older adults. The aim of this review was to present the effects of aging on the periodontal tissues. Aging alone does not lead to critical loss of periodontal attachment in healthy elderly persons. The effects of aging on periodontal tissues are based on molecular changes in the periodontal cells, which intensify bone loss in elderly patients with periodontitis. These effects may be associated with (1) alterations in differentiation and proliferation of osteoblasts and osteoclasts; (2) an increase in periodontal cell response to the oral microbiota and mechanical stress leading to the secretion of cytokines involved in osseous resorption; and (3) systemic endocrine alterations in the elderly people.  相似文献   
997.
Objectives: Internal tapered connections were developed to improve biomechanical properties and to reduce mechanical problems found in other implant connection systems. The purpose of this study was to evaluate the effects of mechanical loading and repeated insertion/removal cycles on the torque loss of abutments with internal tapered connections.
Material and methods: Sixty-eight conical implants and 68 abutments of two types were used. They were divided into four groups: groups 1 and 3 received solid abutments, and groups 2 and 4 received two-piece abutments. In groups 1 and 2, abutments were simply installed and uninstalled; torque-in and torque-out values were measured. In groups 3 and 4, abutments were installed, mechanically loaded and uninstalled; torque-in and torque-out values were measured. Under mechanical loading, two-piece abutments were frictionally locked into the implant; thus, data of group 4 were catalogued under two subgroups (4a: torque-out value necessary to loosen the fixation screw; 4b: torque-out value necessary to remove the abutment from the implant). Ten insertion/removal cycles were performed for every implant/abutment assembly. Data were analyzed with a mixed linear model ( P ≤0.05).
Results: Torque loss was higher in groups 4a and 2 (over 30% loss), followed by group 1 (10.5% loss), group 3 (5.4% loss) and group 4b (39% torque gain). All the results were significantly different. As the number of insertion/removal cycles increased, removal torques tended to be lower. It was concluded that mechanical loading increased removal torque of loaded abutments in comparison with unloaded abutments, and removal torque values tended to decrease as the number of insertion/removal cycles increased.  相似文献   
998.
999.
Osteonecrosis is a progressive clinical condition with significant morbidity, which primarily affects weight-bearing joints and is characterized by the death of the bone, or part of it, because of insufficient circulation. The hip is the most common compromised joint. In osteonecrosis of the femoral head (ONFH), the collapse of the femoral head is a result of mechanically weak bone submitted to a load of weight, and can be associated with incapacitating pain and immobility. Both nonsurgical and surgical treatment options have been used with differing levels of success, and nonoperative treatment modalities such as bisphosphonates, statins, anticoagulants, and extracorporeal shock wave therapy (ESWT) for early-stage disease have been described, but exact indications have not been established yet. The aim of this study was to make a systematic review of the use of ESWT in the treatment of ONFH. MEDLINE, LILACS, and Scielo databases were searched using the keywords “shock wave”, “osteonecrosis”, “avascular necrosis”, “aseptic necrosis” and “femoral head”. The search period was between 1966 and 2009. Only five articles that fulfilled the previously established criteria were obtained. Of these five articles, two were randomized clinical trials, one open label study, one comparative prospective study, and one was a case report. The present review demonstrated that there are no controlled and double-blind studies about the efficacy of ESWT in the treatment of ONFH. On the other hand, the published noncontrolled studies appear to demonstrate some favorable result, which justifies new research in this area.  相似文献   
1000.
To describe utilization of a biosimilar product containing filgrastim (Neutromax®), data of 414 myeloma or lymphoma patients subjected to autologous SCT between 1998 and 2007 were analyzed. Filgrastim was used for mobilization of progenitors (5 days at 300 μg/day) and for the recovery of neutropenia after transplantation (100 μg/day, since day +5). In 2003, the excipient mannitol was replaced by sorbitol. A mean dose of 9.47 × 106 CD34+ cells/kg was infused; 100 neutrophils/mm3 required 5-day treatment; 500 neutrophils/mm3, 6 days and 1000 neutrophils/mm3, 7 days. Neutromax® effect in SCT is similar to reports with other brands. No difference was found between formulations.  相似文献   
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