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This report describes an experimental model of chronic tonsillar herniation and its effects on the spinal cord. In ten rats, a small piece of chemically induced mammary cancer was transplanted to the supraoccipital bone. In all cases, the transplanted cancers grew into the posterior fossa, destroying the supraoccipital bone and compressing the cerebellum extradurally. In six of the ten rats, tonsillar herniation was observed at 8–14 weeks after transplantation. Transdural infiltration of the tumor cells was not apparent in any animal. In those rats with tonsillar herniation (n=6), the spinal cord from the C5 to the T8 segments showed enlargement of the central canal without exception. Histological examination revealed the following changes: stretching and thinning of the ependymal cells; swelling of the astrocytic processes; and extracellular edema, predominantly in the dorsal gray matter, but also in the ventral inner portion of the dorsal column. In the control group (n=4) and those rats without tonsillar herniation (n=4), such histological changes of the spinal cord were not observed. Although the lesions can not be regarded as representing mature syringomyelia, they most likely constitute an earlier evolutionary stage. 相似文献
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Toshikazu Saito M.D. Hideaki Ishizawa M.D. Fumiaki Tsuchiya M.D. Hiroki Ozawa M.D. Naohiko Takahata M.D. 《Psychiatry and clinical neurosciences》1986,40(2):189-194
Abstract: Monoamine and their acid metabolites were determined in the CSF of 18 drug-treated chronic schizophrenic patients with the symptoms of tardive dyskinesia and neuroleptic-induced Parkinsonism (Parkinsonism). Six healthy volunteers were used as the control group.
The norepinephrine (NE) levels were found to be significantly higher in the patients with tardive dyskinesia than in the controls. Furthermore, elevated CSF NE levels were also observed in the patients with Parkinsonism. Epinephrine (E) and Dopamine (DA) were not present in the CSF of the control group, whereas measurable levels of DA could be detected in 4 out of 9 and E was found in 8 out of 9 patients with tardive dyskinesia. The mean concentration of HVA was slightly but not significantly elevated in the patients with tardive dyskinesia and Parkinsonism. The mean values of CSF 5-HIAA were all within the normal range in both patient groups. From the above results, it was suggested that abnormal adrenergic activity rather than abnormal dopaminergic activity may play an important role as a mechanism in the etiopathogenesis of extrapyramidal disorders. Furthermore, in the patients with Parkinsonism, CSF neurochemical observations were similar to those of the patients with tardive dyskinesia in this study. It may help to explain the clinical coexistence of tardive dyskinesia and neuroleptic-induced Parkinsonism. 相似文献
The norepinephrine (NE) levels were found to be significantly higher in the patients with tardive dyskinesia than in the controls. Furthermore, elevated CSF NE levels were also observed in the patients with Parkinsonism. Epinephrine (E) and Dopamine (DA) were not present in the CSF of the control group, whereas measurable levels of DA could be detected in 4 out of 9 and E was found in 8 out of 9 patients with tardive dyskinesia. The mean concentration of HVA was slightly but not significantly elevated in the patients with tardive dyskinesia and Parkinsonism. The mean values of CSF 5-HIAA were all within the normal range in both patient groups. From the above results, it was suggested that abnormal adrenergic activity rather than abnormal dopaminergic activity may play an important role as a mechanism in the etiopathogenesis of extrapyramidal disorders. Furthermore, in the patients with Parkinsonism, CSF neurochemical observations were similar to those of the patients with tardive dyskinesia in this study. It may help to explain the clinical coexistence of tardive dyskinesia and neuroleptic-induced Parkinsonism. 相似文献
46.
Seiji Kinugasa Shuichi Tachibana Manpei Kawakami Tatsuhiko Orino Ryuichi Yamamoto Shinjiro Sasaki 《Surgery today》1998,28(3):335-338
(Received for publication on Nov. 14, 1996; accepted on May 12, 1997) 相似文献
47.
Key words reversal of neuromuscular blockade pancuronium - neostigmine 相似文献
48.
K Tatemoto K Goto T Uno M Yoshimatu T Ono Y Hisa M Tachibana T Ohtsuki A Tohno-oka 《Gan no rinsho》1989,35(10):1153-1159
An inappropriate antidiuretic hormone secretion (SIADH) has been recognized as the cause of hypotonic hyponatremia, and the occurrence of this syndrome, accompanied by an ADH-producing adenocarcinoma in the nasal cavity, is reported. In February, 1987, a 50-year-old male, showing sights of delirium, disorientation, and irritability was admitted to the hospital. The patient was observed to be healthy, except for a neck lymphnode metastasis that was present up to the time of his hospitalization. The hyponatremia was incidentally found, although dehydration or intravascular volume depletion were not noted. These neuropsychiatric symptoms were considered to be associated with hyponatremia due to SIADH. He had had a partial maxillectomy, a neck dissection, and irradiation to the nose and nasal cavity 32 months earlier, and then underwent a surgical resection of the neck metastasis; he had a total of 10 other operations before the onset of the symptoms. Upon initial inspection, since neither an intracranial invasion nor a brain metastasis was found, we diagnosed that his symptoms were due to an autonomic disturbance caused by surgical and mental "stress". When he died of cardiac failure due to a mediastinal invasion 8 months after the onset of SIADH, tumor tissues was extirpated in an autopsy and was then cultured. In this manner, it was proved that the tumor cells had been producing ADH. This procedure clarified that the syndrome had resulted from an ADH-producing tumor of the nasal cavity. 相似文献
49.
Shirai Y Hashimoto M Kato R Kawamura YI Kirikae T Yano H Takashima J Kirihara Y Saito Y Fujino MA Dohi T 《Journal of clinical immunology》2004,24(1):42-52
Despite the huge number of colonized Gram-negative bacteria in the colon, the normal colon maintains its homeostasis without any excessive immune response. To investigate the potential mechanisms involved, human colonic lamina propria mononuclear cells (LPMCs) obtained from uninflamed mucosa were cultured with lipopolysaccharide (LPS) prepared from Bacteroides vulgatus (BV-LPS) or Bacteroides fragilis (BF-LPS), as representatives of indigenous flora, or pathogenic Salmonella minnesota (SM-LPS). Colonic LPMCs failed to produce inflammatory cytokines in response to any type of LPS. Colonic macrophages barely expressed mRNA for MD-2, an essential association molecule for LPS signaling via Toll-like receptor 4. Further, BV-LPS induced CD25 and Foxp3 expression in lymphocytes and CD4(+)CD25(+) cells expressed IL-10 mRNA. Thus, the low expression of functioning LPS receptor molecules and induction of IL-10-producing CD4(+)CD25(+) lymphocytes by indigenous LPS may play a central role in the maintenance of colonic immunological homeostasis. 相似文献
50.
Study on effects of life review activities on the quality of life of the elderly: a randomized controlled trial 总被引:1,自引:0,他引:1
BACKGROUND: The objective of this study was to evaluate the mid-term efficacy of life review activities on the quality of life (QOL) of the elderly by conducting a randomized controlled trial, and to identify the factors that should be taken into consideration when conducting life review activities. METHODS: Written consent was obtained from 80 of the 97 eligible elderly persons. After randomly assigning them to two groups, an intervention group and a control group, group life review activities were conducted in the intervention group and discussion activities about health were conducted in the control group. In both the intervention group and the control group, life satisfaction, self-esteem, depression, and hopelessness were evaluated using self-rating scales at three points: at baseline, immediately after completion of the 8 weeks of sessions, and 3 months after completion of the intervention. RESULTS: Repeated measures analysis of covariance showed significant differences between the two groups in the changes in scores for depression (p = 0.04) and hopelessness (p = 0.04). Regarding the factors that were associated with depression and hopelessness, 3 months after completion of the intervention, depression and hopelessness of a more severe nature at baseline and having greater unresolved conflicts in the past were extracted by multiple regression analysis. CONCLUSIONS: The results suggested that group life review activities have a role in assisting the developmental stage of old age and supporting mental health, and have mid- to long-term effectiveness in maintaining and improving the QOL of the elderly. 相似文献