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21.
To investigate the influence of daily activity on changes in the physical fitness of people with post-stroke (cerebrovascular disorders) hemiplegia, we evaluated the follow-up exercise load test of 30 ambulatory male patients with post-stroke hemiplegia. Between the times of the two tests, patients had no special supervised training. They were advised by their physicians to exercise according to the result of an exercise-loading test. We determined peak oxygen uptake and O2 consumption at the ventilatory threshold point. After 9.4 months, the mean peak oxygen uptake improved significantly from 17.7 to 21.1 ml/min/kg, and ventilatory threshold point also improved significantly from 11.4 to 13.6 ml/min/kg. Among the nine subjects who returned to their jobs, subjects who previously went to their offices by public transportation showed more improvement in ventilatory threshold point level than did subjects who previously walked to their offices. Among the 21 subjects who did not return to work, those who exercised regularly (primarily by walking) showed more improvement of peak oxygen uptake level than did subjects who did not exercise regularly. In conclusion, people with hemiplegia who are living in the community can improve their physical fitness without formal supervised training by simply increasing their daily activities.  相似文献   
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Summary A monoclonal antibody, termed AD11/8, reactive to microglial cells, was produced by immunization of mice with partially purified amyloid fibrils of senile (neuritic) plaques. With immunoperoxidase staining on human tissues, AD11/8 also recognized macrophages in the red pulp of the spleen, Kupffer cells in the liver, and macrophages in the bone marrow. The results show that AD11/8 recognizes the antigens associated with mononuclear phagocytes lineage. In normal brains a few resting microglial cells were stained in gray matter, and less frequently in white matter. In senile dementia of the Alzheimer type numerous microglial cells were stained intensively and they often formed clusters in gray matter. By double immunostaining with AD11/8 and a polyclonal antibody against synthetic amyloid -protein, clustered microglial cells were observed in and around senile plaques with amyloid deposits. Some amyloid plaque cores were surrounded by microglial cell processes. These results indicate that microglial cells may play an important role in senile plaque formation.Supported in part by the Grant-in Aid for Scientific Research from the Ministry of Education, Science and Culture, the grants for Research of Dementia and for Primary Amyloidosis from the Ministry of Health and Welfare, Japan  相似文献   
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Previous studies have demonstrated that plantar cutaneous afferents can adjust motoneuronal excitability, which may contribute significantly to the control of human posture and locomotion. However, the role of plantar cutaneous afferents with respect to their location specificity in modulating the mechanically induced stretch reflex still remains unclear. In the present study, it was hypothesized that electrical stimulation of the ipsilateral heel region of the foot is followed by a modulation of spinal excitability, leading to a facilitation of the soleus motor output. The study was performed to investigate the effect of excitation of plantar cutaneous afferents located around the heel on the soleus stretch reflex. The soleus stretch reflex was evoked by rotating the ankle joint in dorsiflexion direction at two different angular velocities of 50 and 200 degrees s(-1). A conditioning pulse train of non-noxious electrical stimulation was delivered to the plantar surface of the heel at different conditioning test intervals ranging from 5 to 100 ms. Excitation of plantar cutaneous afferents around the heel resulted in a pronounced facilitation of the soleus stretch reflex with magnitude and time course comparable for both velocities. This facilitation was manifested by a significant increase of reflex size for conditioning test intervals from 30 to 70 ms. The observed effect implies a potential functional role of cutaneous afferents in balance control conditions where the ankle is naturally disturbed, e.g., during step reactions to external perturbations.  相似文献   
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We investigated whether malformations of cortical development yield a complex central cortex by studying nine children with malformations of cortical development and seven without malformations who underwent epilepsy surgery following extraoperative subdural somatosensory evoked potential and electrical stimulation to identify the sensorimotor cortex. We analyzed superficial structures of the central cortex, latency, amplitude, and location of N20 and P25. Sensorimotor responses in malformations of cortical development extended across the central sulcus in 1 to 4 of 3 to 12 electrodes (mean 32%) compared with 1 to 6 of 4 to 15 electrodes (mean 12%) in cases without malformations with a statistical significance (P < .05). N20 amplitudes were lower in epileptic than nonepileptic cortices (three with and three without malformations of cortical development) (P < .05). The central vein coursed partially along the central sulcus in eight cases of malformations of cortical development and five cases without malformations. We conclude that the sensorimotor cortex in malformations of cortical development is more complex than in cases without malformations, reduced N20 amplitude is indicative of epileptic sensorimotor cortex, and superficial veins do not indicate the sensory and motor cortical boundary.  相似文献   
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Purpose. For tumor growth, proteolytic remodeling of the extracellular matrix (ECM) is a key factor. To determine proteolytic activity in human glioma cells, fibrinolytic activity, mRNA expression of fibrinolytic factors, and fibrinolytic inhibitors were studied in human glioma cell lines. The effect of platelet activating factor (PAF), a potent mediator of inflammatory and immune responses, on this fibrinolytic activity was also examined. Methods. The fibrinolytic activities of conditioned medium and cell lysates from human glioma cell lines, A172, T98G, U87 and TM1 were studied by fibrin plate zymography. mRNA expression of tissue plasminogen activator (tPA), urokinase-type plasminogen activator (uPA) and plasminogen activator inhibitors (PAI-1, PAI-2) was measured by Northern blot analysis. PAF was added to the medium, and its effects on cell proliferation, fibrinolytic activity, mRNA expression of plasminogens and inhibitors were studied. Results. mRNA expression of plasminogens and inhibitors differed between individual cell lines. Only the medium and cell lysates from A172 cells revealed fibrinolytic activity. A172 cells showed mRNA expression of tPA. PAF at low concentrations, such as 1 nM, stimulated A172 cell proliferation, and high concentrations of PAF inhibited proliferation. PAF stimulated tPA release into the conditioned medium. mRNA expression of tPA was stimulated by low concentrations of PAF and inhibited by high concentrations. Conclusion. The variability of mRNA expression of plasminogen activators (PAs) between different glioma cell lines may indicate that plasminogens and their inhibitors do not directly correlate with brain tumor growth. PAF may be an important factor in the local control of fibrinolytic activity in glioma and its proliferation.  相似文献   
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We present a case of hypothalamic hamartoma in which the signal intensity of the lesion significantly changed during the course of follow-up. To date, stability of the lesion morphology over time has been considered an important diagnostic criterion of hypothalamic hamartoma. Radiologists should be aware that in hypothalamic hamartoma, signal intensity can change during its natural course.  相似文献   
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Major molecular species of human alpha-fetoprotein(AFP), which were separated as single components by serial affinity chromatography with concanavalin A(Con-A) and Lens culinaris agglutinin, were further resolved into several bands by affinity electrophoresis with erythroagglutinating phytohemagglutinin of Phaseolus vulgaris lectin(E-PHA). Among the newly separated main molecular species, both Con-A- and E-PHA-reactive AFP(AFP-1X1) was demonstrated, contrary to the known sugar specificity of Con-A and E-PHA, in addition to molecular species of AFP reacting with Con-A but not with E-PHA(AFP-1X0) and of AFP reacting with E-PHA but not with Con-A(AFP-0X1). AFP-0X1 was formed from AFP-0X0, and AFP-1X1 from AFP-1X0 by neuraminidase treatment; thus, AFP-0X1 and AFP-1X1 represent asialylated and AFP-0X0 and AFP-1X0 sialylated molecular species. AFP-1X1' and AFP-0X0' were present as minor components. AFP-0X0' had no affinity for E-PHA, and the affinity increased in the order of AFP's-0X0(or 0X1), -1X1', -1X1 and -0X1. Proportions of those components varied depending on the pathophysiological conditions of AFP production.  相似文献   
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