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101.
We have immunohistochemically localized fibronectin, lysozyme and alpha-fetoprotein (AFP) in 21 human hepatocellular carcinoma (HCC) tissues obtained by surgical resection at both light and electron microscopic levels. Three distinct distribution patterns of fibronectin (sinusoidal, periacinar, and pericellular patterns) were observed. The sinusoidal and periacinar patterns were mainly observed in HCC of pseudoglandular or trabecular patterns and of Edmondson's grade I or II, whereas the pericellular pattern was observed in HCC of compact or trabecular patterns and of Edmondson's III grade, suggesting that the pericellular fibronectin was rather associated with undifferentiated HCC. Electron microscopic observation of the pericellular fibronectin showed fibronectin to be present in the dilated intercellular spaces where microvilli were moderately developed. We observed intracytoplasmic staining of fibronectin in 2 of the 21 HCC cases. By immunoelectron microscopy, fibronectin was observed in the endoplasmic reticulum (ER) of some HCC cells. In the 21 HCC cases, lysozyme-positive cancer cells were observed in 10 cases, and AFP in 6 cases. At the ultrastructural level, lysozyme was identified in the ER and the perinuclear spaces of HCC cells, suggesting that lysozyme was synthesized by these cells. Lysozyme-positive cases tended to be more frequently observed in cases with the pericellular pattern of fibronectin rather than those with sinusoidal or periacinar patterns. 相似文献
102.
103.
104.
The cardiohemodynamic effect of (+/-)-(E)-4-ethyl-2-[(E)-hydroxyimino]-5-nitro-3-hexenamide (FK409), a novel potent vasodilator, was studied in anesthetized open-chest dogs. FK409 (1 to 10 micrograms/kg, i.v.) decreased mean blood pressure, cardiac output and venous return (sum of the flow through the inferior and the superior vena cava). These changes accompanied decreases in left ventricular pressure, in its maximum rate of rise and in right atrial pressure. This cardiovascular profile of FK409 is very similar to those of classical nitrates. 相似文献
105.
Hideyuki Iwai Ryuji Koike Jun Ogawa Takahiko Sugihara Hiroyuki Hagiyama Kenji Nagasaka Yoshinori Nonomura Junko Nishio Toshihiro Nanki Rieko Tsubata Hitoshi Kohsaka Tetsuo Kubota Nobuyuki Miyasaka 《Nihon Rinshō Men'eki Gakkai kaishi》2002,25(3):270-276
A 36-year-old man was admitted to a hospital with complaints of fever, polyarthralgia and dyspnea. Erythema was observed on his face, extensor surface of the fingers and extremities, and a chest X-ray revealed massive bilateral pleural effusion. He had no sign of myopathy at this point. Pleural fluid was proved to be exudative and contained extremely high levels of hyaluronic acid. He was also complicated with interstitial pneumonitis and was given a pulse therapy with methyl prednisolone followed by daily administration of 55 mg prednisolone (PSL). Twenty days after the commencement of the therapy, pleural effusion decreased but muscle weakness gradually appeared, accompanied by elevation of myogenic enzymes. Myogenic changes on electromyogram, and irregularity of the muscle fibers with slight inflammatory cell infiltrates in a biopsy specimen were demonstrated. He was transferred to our hospital, and a diagnosis of dermatomyositis was made. Later, pleural effusion waxed and waned depending on the dosage of PSL, but no other causative disorder was demonstrated by extensive examinations. This case indicates that the pleuritis could be one of the vasculitic manifestations of dermatomyositis. 相似文献
106.
Kei-ichi Katayama Masaki Ueno Hirofumi Yamauchi Hiroyuki Nakayama Kunio Doi 《Experimental and toxicologic pathology》2002,54(3):193-196
Ethylnitrosourea (ENU) is a simple alkylating agent. It induces gene mutations in fetal primordial germ cells (PGCs), and a high incidence of congenital malformations is also found in the offspring of male mice treated with ENU at the embryonic stage. It is also reported that decreases in the fertility rate and weights of the testis and ovary were found in the offspring from dams treated with ENU. In this study, we analyzed the occurrence of apoptotic cell death and the expression of p53 protein which is thought to play an important role in the DNA damage-induced apoptosis after administration of ENU to pregnant rats on day 13 of gestation to obtain a clue for clarifying the toxic effect of ENU on PGCs. Apoptotic cells increased in PGCs in fetal gonads from 3 h after treatment. The number of apoptotic PGCs peaked at 6 h and gradually decreased towards 24 h after treatment. On the other hand, p53-positive PGCs increased from I h after treatment, prior to the induction of apoptosis. The number of p53-positive PGCs peaked at 3 h and returned to the control level at 24 h after treatment. These results suggest that ENU induces apoptosis in rat fetal PGCs immediately after its administration to dams and excess cell death by apoptosis may have a close relation to the later occurrence of decreases in the fertility rate and gonadal weight. Moreover, a possible involvement of p53 is suggested in the ENU-induced apoptosis in PGCs. 相似文献
107.
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
108.
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
109.
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
110.
To clarify the role of serotonin in cerebral ischemia, we examined the effects of selective serotonin reuptake inhibitors, citalopram and clomipramine, on ischemic neuronal damage in the gerbil. Pretreatment with citalopram (40 mg/kg i.p.) and clomipramine (20 mg/kg i.p.) protected against neuronal destruction of hippocampal CA1 pyramidal cells following 5 min of forebrain ischemia. Furthermore, microdialysis assays showed that a striking increase in extracellular excitatory amino acid levels during ischemia was significantly inhibited by pretreatment with citalopram and clomipramine. However, citalopram (40 mg/kg i.p.) did not alter the extracellular amino acid concentrations in normal gerbils. Thus, serotonin reuptake inhibitors have a protective effect against ischemic neuronal damage. Furthermore, the present result suggests that the protective effect is mediated through prevention of the accumulation of extracellular excitatory amino acids during and after ischemia. 相似文献