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41.
Haruo Nagayama Kounosuke Tsuchiyama Kenji Yamada Jotaro Akiyoshi 《Progress in neuro-psychopharmacology & biological psychiatry》1991,15(6):735-744
1. In our series of experiments the role of serotonin in human depression was studied by using animal models of depression.
2. The results of these studies support the hypothesis that some types of human depression may be primarily due to an excessive transmission of serotonin at the synapse. 相似文献
42.
Y Okamoto K Shimizu K Tamura Y Miyao M Yamada Y Matsui N Tsuda H Mogami 《Brain and nerve》1987,39(10):931-936
Phenytoin is a highly effective anticonvulsant agent that is widely administrated to prevent some kinds of patients with brain tumor. But it has been said that phenytoin may have some immunosuppresive potential for hosts. In this study, we evaluated the effects of phenytoin upon cellular immunity such as NK, CTL and LAK activity in murine models. Fresh splenocytes were taken out from mice (CBA/J, C 3 H/HeN, C 57 BL/6) into which phenytoin had been injected intraperitoneally at a daily dose of 1,000 micrograms for 28 days. The serum concentration of phenytoin in the experimental models was 10-20 micrograms/ml. The cytotoxic activities were estimated by a 4-hr 51Cr release assay. The mitogen-stimulated lymphocyte function was evaluated by 3H-thymidine incorporation into DNA. The NK activity was estimated by cytotoxicity of splenocytes of CBA/J mice against NK-sensitive YAC-1 cells. The cytotoxic T-lymphocyte (CTL) activity was estimated by cytotoxicity of splenocytes of C 57 BL/6 mice which were stimulated in vitro for 5 days by splenocytes of C 3H/HeN treated with mitomycin C, against RSV-M glioma cells. Lymphokine-activated killer (LAK) activity was estimated by cytotoxicity of LAK cells, which were induced from splenocytes of C 3 H/HeN mice by human recombinant interleukin-2 (rIL-2), against syngeneic RSV glioma and allogeneic 203 glioma cells. 3H-thymidine incorporation of splenocytes of C 57 BL/6 mice was reduced significantly (p less than 0.01) in phenytoin-treated mice. The cytotoxicity of splenocytes of non-treated CBA/J mice against YAC-1 cells was 75%, but that of phenytoin-treated CBL/J mice was a few %.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
43.
Kelley Withy MD MS ; January May Andaya; Judith S. Mikami RN MPH ; Seiji Yamada MD MPH 《The Journal of rural health》2007,23(1):84-88
CONTEXT: Health disparities between rural and urban communities are well documented. There are many suggested causes and many proposed solutions but no one-size-fits-all answer. The most successful community interventions have been introduced by communities themselves. However, before communities invest in such interventions, each group must identify and prioritize their needs. PURPOSE: This article describes the Hoshin facilitation method as a practical option assisting communities in assessing their needs and gaining consensus for future steps. METHODS: Thirty-four meetings were held in 11 rural communities in Hawaii using the Hoshin process to identify factors that impact rural health. Themes were identified by constant comparative analysis and thematic frequency described. Commonality of responses between communities was examined. Informal feedback was collected from meeting participants. FINDINGS: There was a great deal of commonality between community responses, with economic factors, drug use, lack of community leadership, lack of health care services and access to services, lack of healthy activities for youth, and poor public education being the most common issues noted. Group involvement in the meetings was high, and the facilitation method received positive feedback from participants. CONCLUSIONS: The Hoshin facilitation method is a very useful tool to help communities rapidly identify and prioritize areas for programmatic attention. 相似文献
44.
X Renming K Ishihara M Sasa H Ujihara T Momiyama Y Fujita N Todo T Serikawa J Yamada S Takaori 《European journal of pharmacology》1992,223(2-3):185-192
The effects of CNK-602A (N-[(6-methyl-5-oxo-3-thiomorpholinyl) carbonyl]-L-histidyl-L-prolinamide), a novel thyrotropin-releasing hormone related analog, were investigated on absence-like seizure and tonic convulsion in the spontaneously epileptic rat (SER), which is a genetically defined double-mutant. When CNK-602A of 0.2-1 mg/kg was given intravenously to the animal, there were no changes in the background EEG except for an increase in low-voltage fast waves concomitant with behavioral alertness. However, CNK-602A suppressed absence-like seizure and tonic convulsion in a dose-dependent manner for over 1 h. These antiepileptic effects of CNK-602A on both seizures were antagonized by pretreatment with haloperidol (1 mg/kg, i.p.). It was found, using a brain in vivo microdialysis method, that CNK-602A at a dose of 1 mg/kg, which inhibits the seizures, increased the release of dopamine in the caudate nucleus. These results suggest that CNK-602A inhibits the seizures of SER in a similar manner to thyrotropin-releasing hormone (TRH), probably by increasing the release of dopamine in the central nervous system. In addition, the antiepileptic effects of CNK-602A were more potent and lasted longer than those of TRH. 相似文献
45.
We have prepared a new material for embolisation: ethylene vinylacetate copolymer dissolved in polyvinyl alcohol. When in contact with blood, polyvinyl alcohol rapidly becomes a soft gel, which is accompanied by wedging of the ethylene vinylacetate copolymer. We analysed the histopathology of intra-arterial microemboli in rats, after intracarotid injection of this material. We confirmed that it was applicable to embolisation for neurosurgical treatment. 相似文献
46.
A 37 year old nurse with the rare combination of idiopathic thrombocytopenic purpura (ITP), Hashimoto's thyroiditis and rheumatoid arthritis (RA) was reported. In 1983, six years before her final diagnosis was made, she presented with purpura over her extremities and swelling of the cervical lymph nodes. Laboratory findings showed the following: platelet count 15 x 10(3)/microliters, the number of megakaryocyte without platelet production in bone marrow was increased, platelet life span (T1/2) 11 min. A diagnosis of ITP was made. In 1984 goiter was noticed. Laboratory data were as follows: T3 502ng/ml, T4 27.0 micrograms/dl, thyroid test x 1,600, microsome test x 409,600. She was diagnosed as having ITP and Hashimotoxicosis. She had been uneventful except temporary hyperthyroidism until 1989 when she developed morning stiffness, polyarthralgia, swelling of PIP joints, contracture of elbow joints and hallux valgus. Laboratory investigation were reported as follows. ESR 111mm/h, platelet count 31 x 10(3)/microliters, platelet associated IgG 800ng/10(7) pl, antinuclear antibody x 2,560, rheumatoid factor 1+, microsome test x 1,600, anti-DNA antibody 3U/ml. Anti-Sm antibody and anti-RNP antibody were not detected. The LE cell test was negative. Schirmer test and sialography were interpreted as normal. These findings confirmed the diagnosis of RA in addition to ITP and Hashimoto's thyroiditis. The combination of RA, ITP and Hashimoto's thyroiditis is extremely rare although these three disorders are classified as autoimmune disease. 相似文献
47.
Hironari Takaishi Osamu Nemoto Masanobu Shiota Toshiyuki Kikuchi Harumoto Yamada Masaaki Yamagishi Yutaka Yabe 《Journal of orthopaedic research》1997,15(4):528-538
To clarify phenotypic alterations of intervertebral disc cells during the repair process, we cloned partial type-II collagen cDNA from rabbits and analyzed the level of expression of type-II collagen mRNA in disc degeneration. An animal model was created by surgical denucleation of rabbit intervertebral discs through, an extraperitoneal approach. Eight animals each from an experimental and a control group were killed at 2, 4, 8, or 16 weeks postoperatively, and the disc samples were used for this study. Round chondrorcyte-like cells that filled the herniated space showed intense signal of type-II collagen mRNA and significant pericellular immunostaining of type-II collagen but no clear staining of type-I collagen. Northern. blot analysis revealed that the expression of type-II collagen mRNA of the repair disc cells was transiently increased at 4 weeks postoperatively. The cells were able to change their morphology in response to mechanical stimulation by surgical denucleation and to induce a significant increase in the gene expression of type-II collagen at an early phase of disc degeneration. The present results indicate the transient enhancement of repair activity in the degenerative process of injured fibrocartilage. 相似文献
48.
T Iwama H Yamada T Andoh N Sakai S Era M Sogami K Kuwata H Watari 《Magnetic resonance in medicine》1992,25(1):78-84
The spin-lattice relaxation time (T1) of water protons and the cross-relaxation time (TIS) between irradiated protein protons and observed water protons were measured in order to study water-macromolecular interactions in ischemic rat brain tissues. Tissues were obtained by bilateral common carotid artery occlusion from stroke-prone spontaneously hypertensive rats. Water, Na, and K contents were measured in ischemic brain tissue at the same time. Water and Na content increased while the TIS value and K content decreased following ischemic insults. The T1 value did not change until 180 min after ischemia had been induced. Changes in the TIS value occurred earlier than changes observed for the T1 value, water, and electrolyte contents. Results indicate that the value of TIS may be useful for detecting cerebral ischemia and that the physical structure of water-macromolecular interaction may be altered soon after ischemic onset in brain tissue. 相似文献
49.
K Nishi M Yamada D Morishita Y Nakamura Y Murata M Fujioka S Muramoto S Murakami K Sasaki M Yasui 《Nihon Kyōbu Shikkan Gakkai zasshi》1991,29(7):904-908
A rare case of a 25-year-old man with pulmonary aspergillosis is reported. Pulmonary bulla and eosinophilic pneumonia in the right upper lobe were diagnosed by chest roentgenogram and transbronchial lung biopsy. Because the patient developed infective bullae during steroid therapy, we performed transcutaneous thoracic drainage and right upper lobectomy. The resected lung tissue contained numerous hyphae of Aspergillus. Around the hyphae of Aspergillus, granulomatous reaction and eosinophilic infiltration were observed. Antibodies against Aspergillus were detected in the serum of the patient. The number of peripheral blood eosinophils decreased after right upper lobectomy. These findings suggest that pulmonary bullae and eosinophilic pneumonia may be a rare manifestation of pulmonary aspergillosis. 相似文献
50.