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991.
992.
993.
The authors, after presenting a survey of the literature on the treatment of multiple sclerosis with immunosuppressants, report their experience with Imurek. Of 53 patients with a chronic and progressive course of the disease, objective improvement could be observed in 17. In 20 patients the symptomatology remained unchanged, although 4 of them reported subjective improvement. In 16 patients, progression of the disease could not be stopped. Better results of treatment could be obtained for those forms of the disease where the course was, first, in the form of what may be referred to as outbursts and, later, in a chronic and progressive form. -Possible side effects are pointed out.  相似文献   
994.
Tests of proprioceptive shift (PS), visual shift (VS), and negative aftereffect (NA) were made during 25-min exposure to 20-D displacement and during a subsequent 30-min dark decay period in two separate experiments. Different groups of subjects explored hallways or viewed their active hand during exposure. VS was greatest in hall exposure, while PS was greatest in hand exposure. Larger VS occurred in the second experiment, where test procedures were modified to minimize a tendency to center the target within the momentary or remembered field of view. Substantial and possibly complete VS decay occurred when the initial level of adaptation was high, but although PS decay was substantial, it was not complete. In all conditions, the sum of VS and PS numerically exceeded the NA, and this difference tended to be largest and significant in the hall exposure. Implications of this effect for the two-component additivity hypothesis are discussed.  相似文献   
995.
The authors discuss the international campaign of doctors in opposition to nuclear warfare, "the ultimate scourge of mankind", and give their impressions of the seventh international IPPNW congress held in Moscow from May 29 to June 1, 1987.  相似文献   
996.
997.
How do space and time relate in rhythmical tasks that require the limbs to move singly or together in various modes of coordination? And what kind of minimal theoretical model could account for the observed data? Earlier findings for human cyclical movements were consistent with a nonlinear, limit cycle oscillator model (Kelso, Holt, Rubin, & Kugler, 1981) although no detailed modeling was performed at that time. In the present study, kinematic data were sampled at 200 samples/second, and a detailed analysis of movement amplitude, frequency, peak velocity, and relative phase (for the bimanual modes, in phase and antiphase) was performed. As frequency was scaled from 1 to 6 Hz (in steps of 1 Hz) using a pacing metronome, amplitude dropped inversely and peak velocity increased. Within a frequency condition, the movement's amplitude scaled directly with its peak velocity. These diverse kinematic behaviors were modeled explicitly in terms of low-dimensional (nonlinear) dissipative dynamics, with linear stiffness as the only control parameter. Data and model are shown to compare favorably. The abstract, dynamical model offers a unified treatment of a number of fundamental aspects of movement coordination and control.  相似文献   
998.
The use of glass slides coated with the cationic polymer polydimethyldiallylammonium-chlorid for cell enrichment procedures results in an increasing number of cells on the slicks and changed quantitative results of cell differentiation. These investigations are important for quantitative analysis of cell populations.  相似文献   
999.
1000.
The occurrence of goal-tracking, an unconditioned stimulus (US)-directed autoshaping behavior, was studied in open-field tests with control and classically conditioned pond snails, Lymnaea stagnalis. In an appetitive classical conditioning paradigm with a tactile stimulus as conditioned stimulus (CS) and a localized food stimulus as US a conditioned feeding response built up in the experimental but not in the control animals. In the post-training open-field tests the experimental group alone showed an enhanced attraction toward the source of water current in the environment which previously signalled the arrival of the US but did not act as CS in the classical conditioning procedure. We suggest that this stimulus-directed goal-tracking behavior in Lymnaea is the result of a classical-operant interaction, described so far only in vertebrate animals, and that neurophysiological analysis of this behavior is possible in this snail.  相似文献   
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