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81.
The complex pathway which links the agonist-cell membrane receptor binding to the response at the genome level involves, among other elements, protein kinase C (PKC). Agonists acting at the cell membrane can affect an autonomous nuclear polyphosphoinositide signaling system inducing an activation of nuclear phosphoinositidase activity and a subsequent translocation of PKC to the nuclear region. The fine localization of PKC has been investigated by means of electron microscopy quantitative immunogold labeling in 3T3 mouse fibroblasts, mitogenically stimulated by IGF-I. The enzyme, which in untreated cells is present in the cytoplasm, except for the organelles, and in the nucleoplasm, after IGF-I treatment is reduced in the cytoplasm and almost doubled in the nucleus. The PKC isoform translocated to the nucleus is the alpha isozyme, which is found not only associated with the nuclear envelope but mainly with the interchromatin domains. By using in situ matrix preparations, PKC appears to be retained at the nuclear matrix level, both at the nuclear lamina and at the inner nuclear matrix, suggesting a direct involvement in the phosphorylation of nuclear proteins which are responsible for the regulation of DNA replication.  相似文献   
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The induction of complex bilateral leg muscle activation combined with coordinated stepping movements is demonstrated in patients with complete paraplegia. This was achieved by partially unloading patients who were on a moving treadmill. In comparison to healthy subjects, the paraplegic patients displayed a less dynamic mode of muscle activation. In all other respects leg muscle electromyographic activity was modulated in a similar manner to that in healthy subjects. However, the level of electromyographic activity in the gastrocnemius (the main antigravity muscle during gait) was considerably lower in the patients. During the course of a daily locomotor training program, the amplitude of gastrocnemius electromyographic activity increased significantly during the stance phase, while inappropriate tibialis anterior activation decreased. Incompletely paraplegic patients benefited from the training with respect to performance of unsupported stepping movements on solid ground. In about half of completely paraplegic patients with low muscle tone, no beneficial effect of the training was seen. This may be due to an inhibitory effect on spinal neuronal activity by drugs patients were taking (e.g., prazosin, clonidine, cannabinoids). In this study intrathecal application of clonidine drastically reduced, while epinephrine enhanced locomotor muscle electromyographic activity. The results of this study promise to be significant in the treatment of paraplegic patients.  相似文献   
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In 12 subjects, a pliable, yet unbreakable, intercuspal interference (aluminum shim onlay splint; uniform height of 0.25 mm) was placed between either the right or left maxillary and mandibular second premolars and first molars. During brief and forceful biting (dynamic chewing stroke of about 20 kg force) the interference emulated a semisoft food bolus, and at the end of biting (subsequent static clenching stroke of about 20 kg force) it emulated a rigid metal interference. During dynamic/static biting, rotational electrognathography measured maximum frontal and horizontal plane torque of the right and left mandibular condyles. Eleven subjects (92%) showed frontal plane upward rotation (mean of 1.0 degree) of the condyle contralateral to the interference, and one subject (8%) showed frontal plane upward rotation (0.4 degree) of the condyle ipsilateral to the interference. Two subjects (17%) showed no horizontal plane rotation; seven subjects (58%) showed backward rotation (mean of 0.4 degree) of the condyle contralateral to the interference; and three subjects (25%) showed backward rotation (mean of 0.3 degree) of the condyle ipsilateral to the interference. It is suggested that, in the presence of an occlusal interference, mastication may have both short- and long-term detrimental effects.  相似文献   
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One hundred patients showed signs and symptoms of temporomandibular joint disorder, were participated in a one year follow up study. The patients were randomly divided into four groups: Acuhealth treatment (group A), occlusal splint therapy (group B), Acuhealth and occlusal splint therapy (group C), and control (group D). Each group comprised 25 patients. The patients were examined before and 3, 6, and 12 months after treatment. At the three month evaluation, the patients who were not satisfied with the treatment outcome were offered additional treatment. The result showed that 87% of the patients treated by Acuhealth unit, 77.3% of the patients treated with occlusal splint therapy, and 91.3% of the patients received Acuhealth and occlusal splint therapy were improved subjectively and clinically after 3 months follow-up. The patients who responded well to treatment initially also responded well in the long run. The study showed that the Acuhealth unit proved to be an ideal early therapy for TMD, and complemented later with occlusal splint.  相似文献   
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The development of ulceration and ulcer complications by nonsteroidal anti-inflammatory drugs (NSAIDs) is now well established. Gastric erosions occur in about 60% of patients receiving long-term NSAID therapy. Many clinicians consider such erosions benign in nature and not requiring therapeutic intervention. Recent evidence, however, indicates that gastric erosions predispose rheumatic patients to frank ulcerations and ulcer complications. This brief overview summarizes the clinical dilemma in the diagnosis and treatment of NSAID-induced gastric erosions. Current data suggest that misoprostol has important therapeutic benefits for the treatment and prevention of gastric erosions in patients receiving long-term NSAID therapy.  相似文献   
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