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81.
82.
Ho  CP; Kim  RW; Schaffler  MB; Sartoris  DJ 《Radiology》1990,176(1):171-173
Dual-energy radiographic absorptiometry (DRA) was used to measure the bone mineral content and area density of lumbar vertebrae (L2-L3) in 11 cadavers. These data were subsequently compared with measured ash content and density. Excellent correlation was obtained between bone mineral content measured with DRA and ash weight (r = .963, P less than .0001). The accuracy error in determining mineral content in lumbar vertebrae with DRA was about 9%. In addition, strong correlation was observed between bone mineral density measured with DRA and ash density (r = .881, P less than .0001).  相似文献   
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84.
Although fractures of the clavicle are common, complications are rare. A 41 year old painter developed two uncommon complications of clavicular fracture, mechanical intermittent subclavian artery occlusion and subclavian vein thrombosis. Both conditions were clearly identified on the clinical symptoms and signs and confirmed with dynamic angiography and computerised tomography. Operative intervention led to complete resolution of symptoms.  相似文献   
85.
胚胎嗅鞘细胞移植治疗脑性瘫痪:4例术后4周结果报告   总被引:7,自引:3,他引:7  
目的:观察胚胎嗅鞘细胞移植治疗脑性瘫痪的有效性和安全性。方法:①病例资料:4例因出生时缺血缺氧确诊为脑性瘫痪的患者,男2例,女2例,年龄分别为14岁、岁、个月、岁。嗅92817鞘细胞由北京市虹天济神经科学研究院细胞中心提供,实验经医学伦理委员会批准,4例脑性瘫痪患者均签署知情同意书。②实验方法:根据术前MRI或CT片,患者均在局麻下行微创立体定向嗅鞘细胞移植术,选取双额放射冠为注射靶点,每侧注射1.0×106个细胞。术后给予止血、抗感染、康复等常规处理。③实验评估:分别于嗅鞘细胞移植前、移植后4周采用脑瘫综合功能评定量表、脑瘫日常生活能力量表评价患者神经功能及生活质量的改善。结果:①嗅鞘细胞移植术后4周,4例患者较术前均有不同程度的神经功能改善,未出现手术并发症。②脑瘫综合功能评定总分:病例1由92.5分增至94分,病例2由55分增至56分,病例3由10.5分增至11.5分,病例4由9.5分增至13分。③脑性瘫痪日常生活能力量表总分:病例1由82.0分增至83.5分,病例2无变化,为16.5分,病例3由5.0分增至7.5分,病例4由5.0分增至8分。结论:嗅鞘细胞移植治疗脑性瘫痪患者近期评价安全可行,可部分改善神经功能与生活质量,长期效果有待进一步随访。  相似文献   
86.
87.
Mirror neurons are a distinct class of neurons that discharge both during the execution of a motor act and during observation of the same or similar motor act performed by another individual. However, the extent to which mirror neurons coding a motor act with a specific goal (e.g., grasping) might also respond to the observation of a motor act having the same goal, but achieved with artificial effectors, is not yet established. In the present study, we addressed this issue by recording mirror neurons from the ventral premotor cortex (area F5) of two monkeys trained to grasp objects with pliers. Neuron activity was recorded during the observation and execution of grasping performed with the hand, with pliers and during observation of an experimenter spearing food with a stick. The results showed that virtually all neurons responding to the observation of hand grasping also responded to the observation of grasping with pliers and, many of them to the observation of spearing with a stick. However, the intensity and pattern of the response differed among conditions. Hand grasping observation determined the earliest and the strongest discharge, while pliers grasping and spearing observation triggered weaker responses at longer latencies. We conclude that F5 grasping mirror neurons respond to the observation of a family of stimuli leading to the same goal. However, the response pattern depends upon the similarity between the observed motor act and the one executed by the hand, the natural motor template.  相似文献   
88.
89.
J P Rosso  H Rochat 《Toxicon》1985,23(1):113-125
When the venom of the scorpion Androctonus mauretanicus mauretanicus was submitted to purification procedures, ten proteins were obtained; six were lethal to mice and four were devoid of toxicity in the biological tests used. The ten molecules were characterized by their amino acid composition, and among them toxin V and polypeptide P2 by their amino acid sequences. Peptide P2 (35 amino acid residues), a structural homologue of the so called Buthus epeus short 'insectotoxins' I1 and I5, was inactive on fly larvae and absent from the 'manual venom' obtained by manual handling and excitation of the scorpions.  相似文献   
90.
Background: Air pollution and obesity are hypothesized to contribute to accelerated decline in lung function with age through their inflammatory properties.Objective: We investigated whether the previously reported association between improved air quality and lung health in the population-based SAPALDIA cohort is modified by obesity.Methods: We used adjusted mixed-model analyses to estimate the association of average body mass index (BMI) and changes in particulate matter with aerodynamic diameter ≤ 10 µm (PM10; ΔPM10) with lung function decline over a 10-year follow-up period.Results: Lung function data and complete information were available for 4,664 participants. Age-related declines in lung function among participants with high average BMI were more rapid for FVC (forced vital capacity), but slower for FEV1/FVC (forced expiratory volume in 1 sec/FVC) and FEF25–75 (forced expiratory flow at 25–75%) than declines among those with low or normal average BMI. Improved air quality was associated with attenuated reductions in FEV1/FVC, FEF25–75, and FEF25–75/FVC over time among low- and normal-BMI participants, but not overweight or obese participants. The attenuation was most pronounced for ΔFEF25–75/FVC (30% and 22% attenuation in association with a 10-μg/m3 decrease in PM10 among low- and normal-weight participants, respectively.)Conclusion: Our results point to the importance of considering health effects of air pollution exposure and obesity in parallel. Further research must address the mechanisms underlying the observed interaction.Citation: Schikowski T, Schaffner E, Meier F, Phuleria HC, Vierkötter A, Schindler C, Kriemler S, Zemp E, Krämer U, Bridevaux P-O, Rochat T, Schwartz J, Künzli N, Probst-Hensch N. 2013. Improved air quality and attenuated lung function decline: modification by obesity in the SAPALDIA cohort. Environ Health Perspect 121:1034–1039; http://dx.doi.org/10.1289/ehp.1206145  相似文献   
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