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91.
Summary Histological, ultrastructural and morphometrical observations on Clarke's column were carried out in 18 patients with sporadic amyotrophic lateral sclerosis (ALS) and 15 age-matched control subjects. Of the 18 ALS patients 6 had been on a respirator before death. Bunina bodies were found in the neuronal cytoplasm in 7 of the 12 non-respirator-supported ALS patients and in 3 of the 6 respirator-supported patients. The number of spheroids was significantly higher in the non-respirator-supported patients (P<0.01) than in the control subjects; however, the number in the respirator-supported patients was about equal to that in the controls. The number of neurons in Clarke's column in the non-respirator-supported ALS patients was not reduced, but in the respirator-supported patients they tended to disappear with time after respiratory support. These findings suggest that Clarke's column neurons are also involved primarily in the disease process in sporadic ALS. However, they may begin to disappear only after the patients require respiratory support.Supported in part by a research grant for CNS degenerative diseases from the Ministry of Health and Welfare, Japan 相似文献
92.
本文对从事京剧打击乐的55人(110耳)进行了听力调查及动态观察。利用图表进行对比分析,发现110耳中高频听力损伤89耳,占81%;语频听力损伤32耳,占29.1%;其中伴有高频耳鸣78耳,占70.9%。动态观察30人(60耳),均为永久性听阈阈移。高频听力损伤最早出现的频率是4kHz,并见典型“V”谷,符合噪声性聋的诊断。 相似文献
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95.
本研究以豚鼠皮层听觉诱发电位反应阈为指标,采用自体或群体对照方法,观察0.1Hz极低频磁场对豚鼠听力的影响。结果表明,豚鼠经50mT(毫特)、4h,100mT、48h及10mT、4周暴露后,听阈降低;50mT、48h,20mT、4周暴露后听阈无明显变化。提示0.1Hz极低频磁场对豚鼠听敏度无不利的影响,在某些暴露条件下,听敏度尚有改善。 相似文献
96.
现察口腔修复临床电刀龈成形术的效果。方法:对81例口腔修复门诊牙体缺损患者用电刀进行牙龈成形术并定期复诊观察。结果:81例术后牙龈全部达到修复要求而立即修复,其中70例术后牙龈稳定,占总数的86.4%。结论:电刀龈成形术是口腔修复临床上一种可行的治疗手段。 相似文献
97.
选择62例拔除第一双尖牙的样本,分为平弓丝组、带“U”型阻滞曲组、固定舌弓组,采用方丝弓细丝弓技术,以磨牙作支抗拉尖牙向远中移动,对支抗磨牙进行观察。为期4周的观察发现,平弓丝组、带“U”型阻滞曲组的支抗磨牙均有近中舌向扭转,第二双尖牙中央窝间距亦比治疗前减少;而固定舌弓组支抗磨牙未见有近中舌向扭转。作者认为:以磨牙为支抗移动尖牙时,应注意支抗控制。本文对力的使用及支抗失控的预防、处理问题进行了讨论。 相似文献
98.
D. Agnusdei G. Crepaldi G. Isaia G. Mazzuoli S. Ortolani M. Passeri L. Bufalino C. Gennari 《Calcified tissue international》1997,61(2):142-147
One hundred ninety-eight postmenopausal women (aged 50–65 years) with vertebral bone density (VBD) 1 SD below the mean value
for normal, age-matched, postmenopausal subjects were enrolled in six Italian centers and 134 completed 2 years of treatment.
All subjects were randomly allocated to a 2-year treatment with oral ipriflavone (200 mg t.i.d.) or a matching placebo, according
to a double-blind, parallel group design. All patients also received an oral daily calcium supplement of 1 g as calcium carbonate.
VBD and markers of bone turnover were measured at baseline, and every 6 months. A complete routine analysis of liver and kidney
functions along with hematological parameters were measured before and at the end of treatment period. The valid completers
analysis showed a significant increase of VBD in ipriflavone-treated women with average percent changes of +1.4 after 1 year,
and +1% at the end of treatment period (P < 0.05). The placebo group presented a significant decrease of VBD after 2 years of treatment (P < 0.05). The difference between treatments was significant (P < 0.01). The intention to treat analysis confirmed the significant decrease of VBD in the placebo group, with no changes
in ipriflavone-treated women. Skeletal ALP significantly decreased in ipriflavone-treated women (P < 0.05). Serum BGP and urine HOP/Cr showed a significant decrease only in ipriflavone-treated women, suggesting an inhibitory
effect on bone turnover rate. Adverse reactions, mainly gastrointestinal, occurred to a similar extent in the two treatment
groups. The evaluation of patients' compliance, assessed by residual tablets count, revealed a drug intake of more than 80%
after 2 years in 92.5% and 92.8% of patients treated with ipriflavone or placebo, respectively. This study demonstrates that
ipriflavone can prevent bone loss in postmenopausal women with low bone mass.
Received: 1 April 1996 / Accepted: 5 March 1997 相似文献
99.
目的用畸变产物耳声发射(distortion-product otoacoustic emission,DPOAE)来观察系统性低血压和慢性进行性听力损伤的关系。方法实验组为34例体检中发现的系统性低血压患者(诊断标准:舒张压<60mmHg,收缩压<90mmHg),对照组由年龄、性别相匹配的30例正常人组成,两组在同一实验室中进行了生化、心血管、耳鼻咽喉专科和纯音测听、声阻抗、DPOAE等听力学检查。将两组的各项结果进行比较。结果实验组DPOAE听力图结果显示16例患者有一个以上频率轻到中度的听力损伤,主要在低频范围。与对照组相比,实验组的DPOAE幅值在一个以上的频率低下甚至缺失。结论系统性低血压有可能是导致耳蜗功能损伤的因子之一,而DPOAE可作为早期监测此类患者耳蜗功能损伤情况的有效工具。 相似文献
100.
Pathophysiological components of irritant contact dermatitis caused by 3 chemically-different irritants were investigated. 20 healthy volunteers were patch tested with sodium lauryl sulphate, nonanoic acid and hydrochloric acid on the flexor side of the upper arm. The skin response was evaluated after 24, 48 and 96 h by visual scoring and measured by the following bioengineering methods: transepidermal water loss measurement, electrical conductance for measurement of skin hydration, laser Doppler flowmetry for measurement of cutaneous blood flow and 20 MHz ultrasound A-scan for measurement of skin thickness. In spite of homogeneous inflammatory responses, significant differences in the severity of the injury to the skin barrier function caused by the different irritants were found. Also significant differences between irritants were found in the time course of development of maximum irritant reactions. Bioengineering methods indicating inflammatory responses (measurement of blood flow and skin thickness) were helpful in quantifying the irritant response in general, while bioengineering methods indicating epidermal damage (measurement of TEWL and electrical conductance) were helpful in classifying the individual irritants. 相似文献