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51.
Performing a complex sequential finger movement requires the temporally well‐ordered organization of individual finger movements. Previous behavioural studies have suggested that the brain prepares a whole sequence of movements as a single set, rather than the movements of individual fingers. However, direct neuroimaging support for this hypothesis is lacking and, assuming it to be true, it remains unclear which brain regions represent the information of a prepared sequence. Here, we measured brain activity with functional magnetic resonance imaging while 14 right‐handed healthy participants performed two types of well‐learned sequential finger movements with their right hands. Using multi‐voxel pattern analysis, we examined whether the types of the forthcoming sequence could be predicted from the preparatory activities of nine regions of interest, which included the motor, somatosensory and posterior parietal regions in each hemisphere, bilateral visual cortices, cerebellum and basal ganglia. We found that, during preparation, the activity of the contralateral motor regions could predict which of the two sequences would be executed. Further detailed analysis revealed that the contralateral dorsal premotor cortex and supplementary motor area were the key areas that contributed to the prediction consistently across participants. These contrasted with results from execution‐related brain activity where a performed sequence was successfully predicted from the activities in the broad cortical sensory‐motor network, including the bilateral motor, parietal and ipsilateral somatosensory cortices. Our study supports the hypothesis that temporary well‐organized sequences of movements are represented as a set in the brain, and that preparatory activity in higher‐order motor regions represents information about upcoming motor actions.  相似文献   
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IL-1 is an endogenous pyrogen produced upon inflammation or infection. Previously, we showed that, upon injection with turpentine, IL-1 is induced in the brain in association with the development of fever. The role of endogenous IL-1 in the brain and the signaling cascade to activate thermosensitive neurons, however, remain to be elucidated. In this report, febrile response was analyzed after peripheral injection of IL-1alpha. We found that a normal febrile response was induced even in IL-1alpha/beta-deficient mice, indicating that production of IL-1 in the brain is not necessarily required for the response. In contrast, IL-6-deficient mice did not exhibit a febrile response. Cyclooxygenase (Cox)-2 expression in the brain was strongly induced 1.5 h after injection of IL-1alpha, whereas IL-6 expression was observed 3 h after the injection. Cox-2 expression in the brain was not influenced by IL-6 deficiency, whereas indomethacin, an inhibitor of cyclooxygenases, completely inhibited induction of IL-6. These observations suggest a mechanism of IL-1-induced febrile response in which IL-1 in the blood activates Cox-2, with the resulting prostaglandin E(2) inducing IL-6 in the brain, leading to the development of fever.  相似文献   
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The fate of protein conjugate of desacetyl-alacepril (DU-1227) and its effect on angiotensin I converting enzyme (ACE) activity in renal hypertensive rats were studied. [14C]DU-1227-protein conjugate was prepared by ultrafiltration method and administered intravenously in rats. Elimination of radioactivity of [14C]DU-1227-protein from plasma after injection seemed much slower than that reported of [14C]alacepril (1-[(S)-3-acetylthio-2-methylpropanoyl]-L-prolyl-L-phenylalanine, DU-1219) given orally. In the plasma unbound fraction, captopril and captopril-cysteine were detected. Most tissue levels were higher than plasma levels. Significant reduction of tissue ACE activity was seen after administration of the conjugate. Radioactivity was mostly excreted in feces. Captopril, captopril disulfide and captopril-cysteine were found as urinary metabolites. These findings indicate that protein-bound DU-1227 readily dissociated and released DU-1227 was converted to captopril in vivo and can therefore participate in prolonged hypotensive effect exerted by alacepril.  相似文献   
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A rare case is reported of pineal metastasis from lung cancer initially caused by neurological abnormalities of pineal tumor. A 70-year-old female suffering from headache and deterioration of consciousness for 1 week was admitted. She also had a tumor on both sides of her neck. On admission, neurological examination revealed disturbance of upward gaze, and CT scans showed hydrocephalus and pineal tumor. The tumor was seen as a slightly high density mass on non-contrast CT, and was homogeneously enhanced after administration of contrast material. Right V-P shunt and excision of the left neck tumor were performed at the same time. Pathological diagnosis of neck tumor was undifferentiated carcinoma metastasized to cervical lymph nodes. Extensive study was made, by bronchial fiberscope and biopsy, in order to find the origin of the malignancy and disclosed a small cell lung cancer of left lower lobe. The patient took radiation therapy for both the whole brain (60 Gy) and for the bilateral cervical regions (45 Gy). Two courses of chemotherapy using CDDP, ADR, VCR and CY were administered. Both the neck and the pineal tumors were markedly reduced in size at the termination of radiation therapy. However, she was readmitted 3 months later because of dyspnea. Chest X-P revealed enlargement of the left-lung tumor. She died on April 22, 1987. General autopsy disclosed invasive enlargement of left lung cancer, however, no remote metastasis was found. Examination of pineal region showed only necrotic pineal tissue, and no tumor cell was seen in either macroscopic or microscopic study.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Abstract: The results of various biochemical examinations in 14 patients with cirrhosis (6 males and 8 females) with muscle atrophy at the thenar and hypothenar eminence (muscle atrophy group; mAG) were compared with those in 13 patients (8 males and 5 females) with cirrhosis without muscle atrophy at these sites (non-muscle atrophy group; NmAG). All patients were elderly men and women (mAG and NmAG, mean age, 69±3 years and 60±7, respectively). In most mAG patients, muscle atrophy was accompanied by palmar erythema. Muscle atrophy was histologically demonstrated by biopsy. Furthermore, electromyography and magnetic resonance study of the cervical spinal cord revealed that the atrophy was of myogenic rather than neurogenic origin. The Child-Pugh score, body mass index and sex hormone level in urine (total 24 h) in the two groups were compared along with the biochemical results. There were no significant differences between the two groups in urine estrogen and testosterone levels. The urinary creatinine excretion was significantly reduced in mAG. The creatine phosphokinese, lactate dehydrogenase isoenzyme and aldolase levels in serum did not differ significantly in the two groups, whereas the serum albumin level was significantly increased in NmAG. Significant differences were observed only for the serum albumin level, age and body mass index. Thus, we consider that palmar muscle atrophy in patients with cirrhosis is not due to hormonal excess in serum, but may be attributable to advanced age and diminished physical strength.  相似文献   
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CT pictures of 26 cases of advanced gastric cancer were reviewed. All the cases of gastric cancer were staged surgically and also histologically. 1) Gastric cancer was enhanced intensely. 2) About the diagnosis of the extension of the tumor, there were many problems to be solved in the future, but the result of final staging was satisfactory. 3) With further advent of technology and methodology in the field of CT, CT will play an important role in staging diagnosis of gastric cancer.  相似文献   
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