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11.
12.
Tremor disabled subjects were tested in two dimensional tracking tasks. The subjects had action tremor due to various etiologies. Both continuous and discrete targets were used. Displacement sensing and force sensing joysticks were compared. The effect of filtering of the control signal was evaluated. Position and velocity control were compared. While individuals were found to benefit from various combinations of control setups, no single control modification or combination of modifications was beneficial to all. It remains necessary to adapt manual control interfaces to the needs of the individual disabled person. Most customizing can be implemented with software. 相似文献
13.
In a test of the possible antagonistic interaction between cholecystokinin (CCK) and morphine, morphine-dependent rats were injected with one of three doses of CCK or with naloxone immediately following the consumption of a novel saccharin solution. Whereas opiate-dependent rats injected with the opiate antagonist naloxone acquired an aversion to the saccharin solution (and displayed a dramatic weight loss), CCK was without effect. These data were discussed in relation to the possible pharmacological antagonism between CCK and the opiates. 相似文献
14.
Reversible electroencephalogram changes associated with administration of baclofen in a quadriplegic patient: case report 总被引:2,自引:0,他引:2
We present the case of a spastic quadriplegic who developed mental symptoms which resolved when his Baclofen was discontinued. Of interest was the presence of EEG abnormalities similar to those described in cats receiving this drug. These abnormalities, previously unreported in humans, resolved upon discontinuing Baclofen therapy. 相似文献
15.
The effect of a 14-valent pneumococcal polysaccharide vaccine on morbidity from acute lower respiratory tract infection (ALRI) was determined in a randomized double-blind controlled trial in children under the age of 5 years living in the Paupa New Guinea highlands. The vaccine did not protect against mild ALRI. Vaccine efficacy in the study as a whole was 28% for moderate/severe ALRI, which was not statistically significant though consistent with the significant effect on mortality. Children entered the trial in five separate cohorts 4 months apart. The incidence of disease and vaccine efficacy varied between cohorts and with age. There was no vaccine effect in the first cohort, which had a much higher proportion of older children. The effect was greatest and statistically significant among those groups encountering an epidemic of moderate and severe ALRI at a young age. It was therefore in children at the most vulnerable age in times of greatest incidence of disease that the vaccine had its most potent effect. It is postulated that the efficacy of pneumococcal vaccine is dependent on the predominant invading serotypes in the period after vaccination, the age at which children develop immunocompetence to specific vaccine serotypes, and the levels of naturally acquired specific immunity already present in children at the time of vaccination, and that for all of these conditions there will be a cohort effect. 相似文献
16.
Propositional and response processes as distinguishable and equally important aspects of conditioning: some clarifications 总被引:1,自引:0,他引:1
Martin and Levey's (1988) commentary on our 1987 chapter points to the need for clearer definition of terms and much more open debate in the area of learning and conditioning. While raising some good points for further discussion, their characterisation of some issues appears to be based on a number of misinterpretations and misrepresentations of our position, and we attempt here to correct these functions. Issues which we regard as misinterpreted are those of truth value as a criterion of the cognitive, the epistemological status of a cognition as opposed to the object of the cognition, and the nature of propositional versus non-propositional learning theories. Issues which are misrepresented are those of our position on the nature of conditioning (which is called cognitive by Martin and Levey, but which is, in fact, a dual-process view), formal versus content-oriented distinctions, and the nature of human and non-human learning processes. Despite these differences between Martin and Levey and ourselves, it is apparent that such debates are necessary for furthering our understanding of the complexity and multiplicity of the processes involved in learning. 相似文献
17.
Rupert C M Jones Shirley Copper Oksana Riley Frank Dobbs 《The British journal of general practice》2002,52(480):567-568
Pulmonary rehabilitation is an effective intervention for patients with chronic obstructive pulmonary disease (COPD). It is usually available only through selected hospitals. A pilot study was undertaken to see if pulmonary rehabilitation performed by the primary health care team in one practice was feasible. Fourteen patients were recruited; 13 completed the programme and one year of follow-up. The programme was well received by patients and staff. There were not enough suitable patients among a practice list of 10,500 to justify the running of this programme for a single practice; one primary care group would suffice 相似文献
18.
Nucleotide polymorphism in colicin E1 and Ia plasmids from natural isolates of Escherichia coli. 总被引:2,自引:0,他引:2 下载免费PDF全文
M A Riley Y Tan J Wang 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(23):11276-11280
We examined DNA sequence polymorphism for the colicin gene clusters of seven ColE1 and six ColIa plasmids obtained from natural isolates of Escherichia coli. These gene clusters harbor levels of nucleotide diversity ranging from 0.006 (ColIa) to 0.054 (ColE1). This level of diversity is similar to that observed for chromosomally encoded E. coli genes. However, the variance associated with these estimates is severalfold higher for the plasmid-encoded genes. This increased variance may be due to the differing plasmid population sizes. The pattern of colicin gene cluster polymorphism suggests that the two colicins are evolving in different fashions. ColE1 accumulates polymorphism at an elevated rate in the central domain of the colicin protein, while ColIa polymorphism is distributed evenly along the gene cluster. Comparison of the patterns of divergence between colicin and related proteins of ColIa and Ib and patterns of polymorphism within ColIa suggest that this gene cluster is not evolving in a neutral fashion. These data lend support to the hypothesis that colicin gene clusters may evolve under the influence of diversifying selection. 相似文献
19.
M L Riley R G Israel D Holbert E B Tapscott G L Dohm 《International journal of sports medicine》1988,9(5):320-324
Fasting before an exercise event has been demonstrated to decrease endurance. The purpose of this study was to investigate whether this decrement in performance after fasting could be reversed by ingestion of a carbohydrate solution before and during exercise. Nine fit male subjects ran to exhaustion at approximately 70% VO2max in two counterbalanced trials. The subjects were fasted for 21 h before both trials, and the trials were arranged so that the subjects ingested either a carbohydrate (CHO) or placebo (PL) solution. Although ratings of perceived exertion were significantly lower in the CHO trial, there were no differences in endurance time to exhaustion in the two trials (102 +/- 8 min in the PL trial and 106 +/- 8 min in the CHO trial). There were no differences between trials for the VO2, heart rate, and blood lactate concentrations. As expected, the blood glucose and insulin concentrations were higher in the CHO trial. The respiratory exchange ratio was significantly higher in the CHO trial at 40 min of exercise and tended to be higher at all other times, suggesting a greater reliance on carbohydrate and less on fat as an energy source. This seemed to be confirmed by the significantly lower plasma glycerol concentration, which suggested less fat mobilization in the CHO trial. Ingestion of a glucose polymer solution increased carbohydrate utilization in fasted subjects, but exercise performance was not improved. 相似文献
20.
Antimicrobial resistance in Branhamella catarrhalis 总被引:1,自引:0,他引:1
T V Riley 《The Journal of antimicrobial chemotherapy》1988,21(2):147-150