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51.
Cesare Mondadori Conrad Gentsch Bastian Hengerer Thomas Ducret Jürgen Borkowski Amy Racine Renate Lederer Albert Haeusler 《Psychopharmacology》1992,109(4):383-389
Oral pretreatment with aldosterone or corticosterone blocked the memory-enhancing effects of the calcium antagonist nimodipine, the ACE inhibitor captopril, the NMDA blocker CGP 37 849, and the glycine antagonist strychnine in a passive-avoidance test in mice. The memory-disturbing effects of phenobarbitone, diazepam, CGP 37 849 and scopolamine were not influenced by the hormonal pretreatment. These findings could indicate the involvement of a steroid-sensitive mechanism in drug-induced improvement of memory. In the light of clinical observations showing elevated cortisol levels in Alzheimer patients, the results might also explain why only a limited number of these patients respond to therapy with memory enhancers. 相似文献
52.
A brief mechanical or electrical stimulus to peripheral nerve afferents from the upper and lower limbs elicited a small and inconsistent EMG response of the orbicularis oculi muscles. This response was facilitated when the stimuli were delivered at fixed leading time intervals, of 45–300 ms, with respect to a supraorbital nerve electrical stimulus. Also, the peripheral nerve stimulus modified the conventional blink reflex responses, inducing facilitation of R1 and inhibition of R2. These results suggest a complex processing of sensory inputs from the face and the limbs at the brainstem, where they are probably integrated in a network of interneurons influencing the excitability of facial motoneurons. 相似文献
53.
P. E. Lønning M. Dowsett A. Jones D. Ekse S. Jacobs F. McNeil D. C. Johannessen T. J. Powles 《Breast cancer research and treatment》1992,23(1-2):57-62
Summary The clinical and biochemical effects of combined treatment with the two aromatase inhibitors aminoglutethimide and 4-hydroxyandrostenedione were evaluated in 10 patients suffering from advanced breast cancer. All patients had become resistant to treatment with one of the drugs before having combined treatment. Seven patients progressing on 4-hydroxyandrostenedione who had aminoglutethimide added to their treatment and achieved a further suppression of plasma oestradiol by a mean of 40.0% (p<0.05). Plasma oestrone was suppressed by a mean of 40.6% (p<0.025) and plasma oestrone sulphate was suppressed by a mean of 63.6% (p<0.025). Two of the patients, neither of whom had responded to 4-hydroxyandrostenedione alone, experienced objective tumour regression when aminoglutethimide was given in concert. Three patients progressing on aminoglutethimide who had 4-hydroxyandrostenedione added showed no further suppression of their plasma oestrogen levels, and no tumour regression was observed. These findings suggest a dose-response relationship between plasma oestrogen suppression at low postmenopausal levels and objective tumour response in breast cancer. 相似文献
54.
Dr C. J. Whitters T. W. Macfarlane D. Mackenzie H. Moseley R. Strang 《Lasers in medical science》1994,9(4):297-303
Pulsed Nd-YAG laser irradiation of bacteria has been suggested as a possible means of treating contaminated intra-oral sites
although relatively few studies have been conducted. In this investigation, the antimicrobial activity of a pulsed Nd-YAG
laser was assessed in vitro for a range of oral bacteria using several pulse energies and exposure durations. Pure cultures
of each organism were lased in saline suspensions followed by standard colony counting techniques for test and control samples.
Microbial inhibition was found to be organism-dependent and varied with energy dose and pulse energy. For all nine test species
120-mJ laser pulses proved more efficient than 80-mJ pulses, with 99.9% kills compared with around 90% kills after exposure
to 1800 pulses. These killing activity levels compare favourably with those achieved with other lasers in vitro. 相似文献
55.
Purpose. The inhibitory effects of omeprazole on diazepam metabolism in vitro and in vivo are compared in the rat.
Methods. 3-hydroxylation and N-demethylation of diazepam was investigated in the presence of a range of omeprazole concentrations (2-500µM) in hepatic microsomes and hepatocytes. Zero order infusions together with matched bolus doses of omeprazole were used to achieve a range of steady state plasma concentrations (10-50mg/ L) and to study the diazepam-omeprazole interaction in vivo.
Results. The 3-hydroxlation pathway was more prone to inhibition (KIs 108 ± 30 and 28 ± 11 µM in microsomes and hepatocytes, respectively) than the demethylation pathway (KIs of 226 ± 76 and 59 ± 27 µM in microsomes and hepatocytes, respectively). In both in vitro systems, the mechanism of inhibition was competitive with Km/KI ratios larger than 1 for the 3HDZ pathway and smaller than 1 for the NDZ pathway. There was an omeprazole concentration dependent decrease in diazepam clearance in vivo which could be modelled using a simple inhibition equation with a KI of 57µM (19.8mg/L). In contrast there was no statistically significant change in the steady state volume of distribution for diazepam in the presence of omeprazole.
Conclusions. The in vivo KI for the omeprazole: diazepam inhibition interaction shows closer agreement with the KI values obtained in hepatocytes than with those observed in microsomes. 相似文献
56.
57.
Quality of life was assessed 46 months after an acutemyocardial infarction in a randomized double-blind study ofenalapril versus placebo. Quality of life was evaluated usingthe Nottingham Health Profile (NHP), the Physical Symptoms DistressIndex (PSDI), the Work Performance Scale (WPS) and the LifeSatisfaction Index (LSI). The study comprised 36 women (aged4685 years, mean 68) and 96 males (aged 3981 years,mean 62). Quality of life did not differ significantly between patientstreated with enalapril versus placebo. The scores were (enalaprilvs placebo, mean± SE): average NHP 15.4 ± 2.3vs 17.1 ± 2.3; PSDI 9.5± 1.0 vs 10.8 ±0.9; WPS 19.8 ± 2.0 vs 19.4 ± 1.4; LSI 24.1 ±1.0 vs 22.5 ±1.4. Men reported a better quality of lifethan women on most assessments, and non-smokers and ex-smokersbetter than smokers. Patients with moderate or severe anginapectoris had a worse quality of life measured by PSDI and NHPthan patients with minimal or no angina pectoris. Patients withcongestive heart failure had a higher PSDI than those without(13.6 ± 1.7 vs 9.4 ± 0.7, P<0.05), while nosignificant differences were observed in the NHP scores. In conclusion, quality of life was similar in enalapril andplacebo- treated patients after an acute myocardial infarction.However, it was reduced in patients with angina pectoris orheart failure and in those who continued smoking. 相似文献
58.
Differences between control and focal hand dystonia (FHD) subject groups in short interval intracortical inhibition (SICI) as determined by paired transcranial magnetic stimulation (TMS) can be difficult to demonstrate, due to interindividual differences. The purpose of this study was to compare two TMS methods for assessing SICI in 8 control and 7 FHD subjects. Electromyographic (EMG) data were recorded from the first dorsal interosseous (FDI) muscle of the dominant hands of the control subjects and affected hands of the FHD subjects. The first method used a conventional approach of setting conditioning stimulus intensity to 80% of rest threshold (RTh) and test stimulus intensity to 120% RTh. Three interstimulus intervals (ISIs) were used: 2 msec, 3 msec, and the ISI between 2 and 3 msec that produced optimal SICI. The second method was novel in that test stimulus intensity was set to 150% active threshold (ATh), and conditioning stimulus intensity was varied between 50% and 100% ATh. The latter was determined at the threshold for SICI and expressed as a ratio of ATh. There was no difference between the subject groups in the degree of SICI produced using the first method, at the three ISIs studied. However, using the second method, the SICI threshold:ATh ratio was found to be significantly higher for FHD subjects. This finding suggests that determining the SICI threshold:ATh ratio may be a more sensitive measure of intracortical inhibitory function than more conventional methods. 相似文献
59.
William Perry Arpi Minassian Brian Lopez Leeza Maron Alan Lincoln 《Neuropsychopharmacology》2007,61(4):482-486
BACKGROUND: Prepulse inhibition (PPI) is an operational measure of sensorimotor gating and is impaired in a family of neuropsychiatric disorders characterized by abnormalities of inhibitory function. Adults with autistic disorder (AD) exhibit clinical features of inhibitory deficits, such as restrictive and repetitive behaviors, that may be explained by deficits in sensorimotor gating. METHODS: Acoustic startle reactivity, habituation, and PPI (30-, 60-, 120-msec interstimulus intervals) were assessed in 14 adult men diagnosed with AD and 16 typically developing normal comparison (NC) participants. All participants were administered measures of intelligence and frontal-executive functioning. RESULTS: Adults with AD exhibited significantly less PPI in the 60-msec condition than NC participants, which was correlated with increased ratings of restricted and repetitive behaviors. The groups did not differ on measures of startle amplitude or overall habituation. There was, however, a significant group-by-block habituation effect. Furthermore, PPI was not related to intelligence but was moderately associated with performance on a measure of frontal-executive functioning. CONCLUSIONS: Adults with AD have sensorimotor gating deficits similar to other neurodevelopmental disorders, implicating a failure of normal inhibitory regulation of sensory, motor, and attentional mechanisms. Thus, PPI deficits may be indirectly linked to one of the hallmark features of AD. 相似文献
60.
Jie-Yuan Li Alberto J Espay Carolyn A Gunraj Pramod K Pal Danny I Cunic Anthony E Lang Robert Chen 《Movement disorders》2007,22(6):813-821
Mirror movements (MM) occur in early, asymmetric Parkinson's disease (PD). To examine the pathophysiology of MM in PD, we studied 13 PD patients with MM (PD-MM), 7 PD patients without MM (PD-NM), and 14 normal subjects. Cross-correlogram did not detect common synaptic input to motoneuron pools innervating homologous hand muscles in PD-MM patients. Transcranial magnetic stimulation studies showed no significant difference in ipsilateral motor-evoked potentials between PD-MM patients and normal subjects. The MM side of PD-MM patients showed a slower increase in ipsilateral silent period area with higher level of muscle contraction than the non-MM side and normal subjects. There was less interhemispheric inhibition (IHI) at long interstimulus intervals of 20 to 50 ms in PD-MM than PD-NM. IHI reduced short interval intracortical inhibition in normal subjects and PD-NM, but not in PD-MM. IHI significantly increased intracortical facilitation in PD-MM and PD-NM patients, but not in normal subjects. Our results suggest that MM in PD is due to activation of the contralateral motor cortex. PD-MM patients had reduced transcallosal inhibitory effects on cortical output neurons and on intracortical inhibitory circuits compared to PD-NM patients and controls. These deficits in transcallosal inhibition may contribute to MM in PD patients. 相似文献