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151.
A 40-year-old man presented a painful haemorrhagic plaque on his chest in the same location where a nodular lesion had been presented for many years. After 2 months, the plaque was replaced by a depressed lesion. The lesion diagnosed as an anetoderma was excised and the biopsy showed an atrophic dermatofibroma accompanied by aneurysmatic characteristics.  相似文献   
152.
Sixteen patients (male: 14, female: 2, 41-72 yrs, mean 57.5 yrs) with OSAS were treated by nCPAP in our hospital since 1987. Respiratory disturbance index ranged from 16.5 to 83.1. The longest apnea duration was 35.0-120.5 seconds before the treatment. Two patients were treated with Sleep Easy III (Respironics Inc.) and others with a home made instruments. nCPAP was set at a pressure of 5 to 10 cm H2O. 12 patients (75%) tolerated the device but 4(25%) did not. Polysomnographic parameters before and after nCPAP therapy were compared. The longest apnea duration was 63.1 +/- 23.5 to 40.9 +/- 27.4 seconds (P less than 0.001) and the lowest saturation oxygen was 55.1 +/- 20.4% to 71.4 +/- 18.6% (P less than 0.05). The sleep structure improved but not significant statistically. One of them used nCPAP at home for more than two. years and showed a good long term effect. We concluded that nCPAP is an effective and safe treatment for OSAS. However, patients may be uncomfortable because of the wearing of the nasal mask during sleep.  相似文献   
153.
Inbred mouse strains have different numbers of midbrain dopaminergic neurons; for example, BALB/cJ mice have 20–25% more neurons than CBA/J mice. As the number of cells decrease, for example in Parkinson's disease and in animals with midbrain dopaminergic cell lesions, the activity of their remaining cells increases. The purpose of the present experiment was to determine whether the functional properties of dopaminergic neurons in the ventral tegmental area (nucleus A10) differ in inbred mouse strains which possess different numbers of cells. The firing rate and autoreceptor sensitivity of A10 dopaminergic cells were examined in the in vitro slice preparation in BALB/cJ, C3H/HeJ, CBA/J, and DBA/2J mouse strains. It was observed that the autoreceptors on mouse dopaminergic neurons exhibit pharmacological properties of dopamine autoreceptors; activation of the autoreceptor produced a marked inhibition (50–70%) in cell firing rate by quinpirole (10−8 M), LY-141865 (10−7 M), (+)-3-(3-hydroxyphenyl)-N-n-propyl-piperidine (10−6 M), propyl-norapomorphine (10−5 M) and dopamine (10−4 M), and this inhibition was blocked or reversed by specific dopamine D2 receptor antagonists [(−) sulphide and spiroperidol, 10−6 M]. The baseline firing rates of the A10 cells did not differ among the four inbred strains [range 2.5 ± 0.2 (C3H/HeJ)−3.4 ± 0.3 (CBA/J) spikes/s ±SEM], and there was no significant difference in autoreceptor sensitivity among the mouse strains as assessed either by superfused dopamine (inhibitory dose 50% ≈150 μM), or by superfused quinpirole (inhibitory dose 50% ≈10 nM). These data indicate that differences in A10 cell numbers of 30% do not significantly influence the baseline firing rate or autoreceptor sensitivity of the cells.  相似文献   
154.
OBJECTIVES: The purpose of this study was to determine quality of life (QOL) and exercise performance (EP) in patients with persistent atrial fibrillation (AF) converted to sinus rhythm (SR) compared with those remaining in or reverting to AF. BACKGROUND: Restoration of SR in patients with AF improving QOL and EP remains controversial. METHODS: Patients with persistent AF were randomized double-blind to amiodarone, sotalol, or placebo. Those not achieving SR at day 28 were cardioverted and classified into SR or AF groups at 8 weeks (n = 624) and 1 year (n = 556). The QOL (SF-36), symptom checklist (SCL), specific activity scale (SAS), AF severity scale (AFSS), and EP were assessed. RESULTS: Favorable changes were seen in SR patients at 8 weeks in physical functioning (p < 0.001), physical role limitations (p = 0.03), general health (p = 0.002), and vitality (p < 0.001), and at 1 year in general health (p = 0.007) and social functioning (p = 0.02). Changes in the scores for SCL severity (p = 0.01), functional capacity (p = 0.003), and AFSS symptom burden (p < 0.001) at 8 weeks and in SCL severity (p < 0.01) and AF symptom burden (p < 0.001) at 1 year showed significant improvements in SR versus AF. Symptomatic patients were more likely to have improvement. The EP in SR versus AF was greater from baseline to 8 weeks (p = 0.01) and to 1 year (p = 0.02). The EP correlated with physical functioning and functional capacity except in the AF group at 1 year. CONCLUSIONS: In patients with persistent AF, restoration and maintenance of SR was associated with improvements in QOL measures and EP. There was a strong correlation between QOL measures and EP.  相似文献   
155.
156.
It is well known that migraine has a strong genetic component, although the type and number of genes involved remains unclear. There is evidence to suggest that serotonin-related genes may be involved in the pathogenesis of migraine. To investigate whether the 5-HT1A receptor gene contributes to the risk of migraine we performed an association study of C-1019G promoter polymorphism of the gene in 102 migraineurs and 93 controls. Subjects were of Han Chinese origin. No significant differences in allele (P=0.82) or genotype frequencies (P=0.71) were seen in migraineurs compared with the controls. When migraine with aura, without aura, with family history, without family history were analyzed separately, the frequencies did not vary significantly. Our results suggest that C-1019G in 5-HT1A is not a major genetic risk factor for migraine.  相似文献   
157.
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159.
OBJECTIVE: Studies exploring chronic alcoholism with event-related potentials (ERPs) have shown delayed latency and reduced amplitude of the P300, a long-lasting positive potential reflecting decisional processing. This P300 deficit in alcoholism is generally interpreted as a disturbance in central nervous system inhibition or in memory/attention. The present study aimed at identifying if this electrophysiological deficit is already present on earlier components, and advances a new hypothesis concerning the interpretation of the P300 alteration. METHODS: Patients suffering from alcoholism and matched healthy controls had to detect, in an oddball paradigm, emotional faces among a succession of neutral faces. Behavioral performance and ERP data (recorded from 32 electrodes) were analyzed. RESULTS: In line with previous studies, data showed that alcoholism led to a P300 deficit. Moreover, we observed for the first time that this deficit begins at earlier visual (P100) and face-processing (N170) stages, and we found high positive correlations between P100, N170 and P300 for amplitude and latency values, suggesting cumulative deficits on the cognitive continuum. CONCLUSIONS: We suggest that the P300 deficit observed in chronic alcoholism could be linked to earlier visuo-spatial deficits rather than being an impairment of the specific processes linked to the P300. SIGNIFICANCE: These results call for reconsidering the interpretation of P300 impairments at a fundamental and clinical level, and shows that earlier ERP components must be taken into account in future studies.  相似文献   
160.
In this paper, we address the problem of stable tracking control of a flexible macro-micro manipulator (M(3)) system. A two-layer neural network is utilized to approximate the nonlinear robot dynamic behavior of the M(3) system, and the controllers for the macro and micro arms are developed without any need for prior knowledge of the dynamic model of the controlled M(3) system. A learning algorithm for the neural network using Lyapunov stability theory is derived. It is shown that both the tracking error and the weight-tuning error are uniformly ultimately bounded under this new control scheme. Simulation results are presented and compared to those obtained using a PD controller.  相似文献   
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