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41.
42.
P. Riekkinen Jr. P. Jkl J. Sirvi E. Koivisto R. Miettinen P. Riekkinen 《Brain research bulletin》1991,26(4):633-637
The effectiveness of THA (an anticholinesterae) on scopolamine (0.4 mg/kg) and nucleus basalis (NB) lesion-induced change in neocortical spectral electroencephalography (EEG) were investigated. Scopolamine increased the amplitudes of all the spectral components in waking-immobility. In the movement-related EEG spectral values, only the alpha power was increased. THA 7.5 mg/kg, but not THA 3 mg/kg, could reverse scopolamine-induced amplitude change. NB lesioning increased delta and theta amplitudes, but decreased beta amplitude. Delta amplitude was increased during movement recordings in NB-lesioned rats. THA 7.5 mg/kg and pilocarpine 10 mg/kg, but not THA 3 mg/kg, could partially reverse the increase of delta and theta amplitudes induced by NB lesions. However, the beta power decrease could not be restored with cholinomimetics. This study demonstrates that quantitative EEG activity analysis may reflect the THA-induced restoration of the function of the cholinergic nucleus basalis. 相似文献
43.
大脑中动脉狭窄的TCD与DSA检查比较研究 总被引:1,自引:0,他引:1
目的 :通过大脑中动脉狭窄的TCD检查与DSA检查方法比较 ,为临床提供方便可靠的检查方法。方法 :对经TCD检查确诊为大脑中动脉狭窄 6 0例做DSA检查 ,对两种检查结果进行比较分析。结果 :经TCD确诊为大脑中动脉狭窄病例 ,病变侧狭窄处的血流速度(Vm)均明显高于健侧一倍以上 ,在动脉硬化性狭窄中多伴有“海鸥鸣”或“铁锅炒沙”样杂音 ,且频谱形态呈圆钝或脉动指数值增高的阻力波形。该 6 0例在DSA的检查中均出现不同部位的不同狭窄。结论 :TCD检查具有快速方便、安全、经济、确诊率高的优点 ,可作为脑血管病首选检查手段 相似文献
44.
S. Ohsaki S. Teraoka T. Tojimbara K. Takahasi H. Toma T. Agishi K. Ota 《Transplant international》1992,5(Z1):S100-S103
Prostaglandin E1 (PGE1) was used in renal transplant recipients with living related donors. The drug was given intravenously from day 1 to day 7 after transplantation at a dose of 40 µg/kg twice a day. A total of 45 patients were studied divided into two groups: 25 patients were treated with PGE1 (group B) and the remaining 20 patients did not receive the drug (group A). In group B, 24-h creatinine clearance (Ccr) was 66 ± 12.8 ml/min compared with 40.3 ± 13.4 ml/min in group A on the fifth postoperative day (P < 0.05). Urinary levels of N-acetyl-β-d -glucosaminidase (NAG) and serum levels of platelet factor 4 (PF4) in group B were significantly lower than in group A. On the fourth postoperative day, the urinary excretion of thromboxan B2 (TxB2) in group A was higher than in group B, but not significantly (5.1 ± 3.0 ng/day and 2.8 ± 1.1 ng/day, respectively). Acute rejection occurred in four patients in group B and in 10 patients (40%) in group A. The percentage of Leu2a-positive lymphocytes in group B was higher than in group A. We conclude that postoperative administration of PGE1 improves graft function in kidneys from living related donors. 相似文献
45.
A. C. Metting van Rijn A. Peper C. A. Grimbergen 《Medical & biological engineering & computing》1991,29(4):433-440
A multichannel instrumentation amplifier, developed to be used in a miniature universal eight-channel amplifier module, is
described. After discussing the specific properties of a bioelectric recording, the difficulties of meeting the demanded specifications
with a design based on operational amplifiers are reviewed. Because it proved impossible to achieve the demanded combination
of low noise and low power consumption using commercially available operational amplifiers, an amplifier equipped with an
input stage with discrete transistors was developed. A new design concept was used to expand the design to a multichannel
version with an equivalent input noise voltage of 0·35 μV RMS in a bandwidth of 0·1–100 Hz and a power consumption of 0·6
mW per channel. The results of this study are applied to miniature, universal, eight-channel amplifier modules, manufactured
with thick-film production techniques. The modules can be coupled to satisfy the demand for a multiple of eight channels.
The low power consumption enables the modules to be used in all kinds of portable and telemetry measurement systems and simplifies
the power supply in stationary measurement systems. 相似文献
46.
彩色多普勒超声和二维超声心动图并用,不仅可观察和了解心脏解剖、形态及腔室大小,又能观察血流动力学改变。我们从1991年11月至1992年11月间应用上述方法诊断先天性心脏病共18例,均经我院和外院手术证实:室间隔缺损7例;房间隔缺损6例;动脉导管未闭5例,其中1例误诊为肺动脉瓣狭窄,诊断准确率达94.4%。我们认为彩色多普勒诊断先天性心脏病方法安全,准确无损伤,为临床及术前提供了较可靠的诊断依据,但检查者必须了解心脏及大血管的解剖关系,结合临床才能提高诊断准确率,减少漏、误诊的发生。 相似文献
47.
48.
49.
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
50.
经阴道彩色多普勒诊断未破裂型输卵管妊娠 总被引:1,自引:1,他引:0
本文介绍经阴道彩色多普勒诊断未破裂型输卵管妊娠26例,13例经手术及病理检查证实,13例经临床确诊,符合25例,诊断符合率96.15%;误诊1例,误诊率3.85%。经阴道彩色多普勒检查其二维图像清晰,彩色血流灵敏,能更早发现输卵管妊娠包块内特异的滋养层周围血流及同侧卵巢的黄体血流,使输卵管妊娠在破裂前就能作出诊断,具有较高的临床应用价值。 相似文献