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51.
1. Endothelin-3 (ET-3) elicited relaxations at low concentrations (up to 10(-8) M) and contractions at higher concentrations in dog isolated coronary arteries precontracted with prostaglandin F2 alpha (PGF2 alpha). The relaxation by ET-3 was not affected by endothelium denudation nor treatment with NG-nitro-L-arginine, but was abolished or reversed to a contraction by treatment with indomethacin and markedly suppressed by tranylcypromine, a PGI2 synthetase inhibitor, or diphloretin phosphate, a prostaglandin receptor antagonist. ET-1 produced only concentration-dependent contractions. 2. BQ-123, a new selective ETA receptor antagonist, caused relaxation of the strips contracted with ET-3 in a dose-dependent manner and prevented the ET-3-induced contraction but did not affect the contraction produced by PGF2 alpha. The relaxation caused by ET-3 was enhanced by treatment with BQ-123. 3. It is concluded that the relaxations elicited by ET-3 in dog coronary arteries are mediated via liberation of PGI2 by activation of non-ETA receptors, located in subendothelial tissues, possibly smooth muscle cells, whereas the peptide-induced contractions are mediated via ETA receptors. 相似文献
52.
A 68-year-old woman had pulmonary aspergilloma in the right upper lobe with old cavitary pulmonary tuberculosis. Despite intravenous fluconazole there was no change in the size of the fungus ball. Endobronchial instillation of fluconazole also failed. Subsequently percutaneous instillation of fluconazole was attempted with localized drainage. The fungus ball decreased in size after 8 weeks. Although slight hemoptysis and subcutaneous emphysema occurred in this case, these condition required no treatment. This method of treatment appears to be useful for inoperable cases of pulmonary aspergilloma. 相似文献
53.
K Kunishio C Shinohara K Tokunaga T Matsuhisa E Moriyama H Norikane Y Matsumoto R Tanaka 《No shinkei geka. Neurological surgery》1992,20(9):959-963
164 patients with brain contusion were evaluated with respect to social rehabilitation. 70 out of 134 patients (66.7%), said to have had good recovery or moderate disability by the Glasgow Outcome Scale (GOS), returned to full or partial employment. Factors such as age, Glasgow Coma Scale (GCS) at admission, duration of unawareness, fibrin and fibrinogen degradation product (FDP) were the most important in predicting social recovery. The Wechsler Adult Intelligence Scale (WAIS) was applied in 33 patients. The IQs of the patients who returned to their job fully tended to be higher than those who could not. In the majority of patients, impaired capacity for work was caused not only by physical deficits, but by mental retardation described as such as IQ score. 相似文献
54.
55.
N Kurihara S Takahashi A Ogawa R Shirane M Sasaki K Ishii K Matsumoto T Ishibashi K Sakamoto 《Radiation Medicine》1992,10(2):73-77
Diastemstomyelia is an extremely rare disorder that is seldom found among the Japanese. This paper presents two Japanese patients, a newborn male and a newborn female, with diastematomyelia. CT demonstrated bony spurs more clearly than plain film, and magnetic resonance images indicated split cords and associated anomalies. Although the embryogenesis of diastematomyelia has not been clearly elucidated, the coincidence of levels of associated anomalies and diastematomyelia in our cases and in the literature supports Bremer's embryogenetic explanation of persistent accessory neurenteric canal. 相似文献
56.
Localization of bone marrow-originated cells in the central nervous system (CNS) of the rat was investigated by using bone marrow chimeras. In order to do this, Lewis rats which carry major histocompatibility complex (MHC) class I antigens haplotype 1 (RT1.Al) were reconstituted with (Lew X PVG)F1 (RT1.Al/c) bone marrow cells after lethal irradiation. Transferred bone marrow cells were detected by immunohistochemical staining using a monoclonal antibody, OX27, specific for haplotype c of rat MHC class I antigens (RT1.Ac). The spleen and thymus of chimeric rats were fully reconstituted with transferred F1 cells 4 weeks after bone marrow transplantation. At this stage, mononuclear cells in the subarachnoid space of the CNS expressed OX27 antigen indicating that they were of bone marrow origin. A few OX27-positive blood cells were scattered in the CNS parenchyma 4-12 weeks after reconstitution. Ramified microglia, however, remained OX27-negative. Bone marrow-derived microglia were not observed throughout the period of examination until 24 weeks. In addition, experimental allergic encephalomyelitis (EAE) was induced in chimeric rats in order to augment the expression of MHC class I antigens on microglia. Even under this condition, no OX27-positive microglia were observed. Taken together, ramified microglia might be of neuroectodermal origin and there is little possibility that the microglia are derived from the bone marrow. However, if the ramified microglia are derived from blood cells, the microglia may be expected to have characteristic cell kinetics from the following points: (1) the precursor cells of the microglia may enter the CNS only at the perinatal stage; and (2) even under the condition in which lymphocytes and macrophages enter the CNS as observed in EAE, the precursor cells of the microglia are not supplied from the blood. 相似文献
57.
Masashi Okuro Shigeto Morimoto Takashi Takahashi Kohya Okaishi Takeshi Nakahashi Hiroshi Murai Kunimitsu Iwai Tsugiyasu Kanda Masayuki Matsumoto 《Hypertension research》2006,29(9):655-663
Endothelial function in elderly hypertensive patients with arteriosclerosis obliterans has not been evaluated. We examined whether antihypertensive drugs improve vasodilatory response to reactive hyperemia of the limbs in elderly hypertensive patients (83 +/- 8 [SD] years) without (n=46, 0.9 < or = ankle-brachial pressure index < or = 1.4) and with (n=24) arteriosclerosis obliterans (ankle-brachial pressure index < 0.2). Patients were randomized for treatment with monotherapy of either temocapril (14 with and 26 without arteriosclerosis obliterans) or amlodipine (10 with and 20 without arteriosclerosis obliterans) for 6 months. Blood flows of the forearms and legs were measured by strain-gauge plethysmography. The vasodilatory response to the release of compression of the forearms and thighs at 200 mmHg or 20 mmHg more than systolic blood pressure for 5 min and to sublingual administration of nitroglycerin (0.3 mg) was assessed. The maximum reactive hyperemic flow in 35 legs with arteriosclerosis obliterans was significantly (p < 0.001) decreased compared to the value in legs in the control hypertensive subjects. Moreover, maximum reactive hyperemic flow in the forearms of patients with arteriosclerosis obliterans was significantly (p = 0.002) decreased compared to that in the control subjects. Blood pressure was similarly decreased by treatment with temocapril or amlodipine. Response to nitroglycerin (0.3 mg) was not changed by either drug. Treatment with temocapril significantly improved maximum reactive hyperemic flow of not only the legs and forearms in control hypertensives but also the legs and forearms in patients with arteriosclerosis obliterans, and attenuated the worsening of activity of daily living in these patients, although treatment with amlodipine did not. These results suggest that the angiotensin-converting enzyme inhibitor temocapril has a beneficial effect on endothelial function in elderly patients with arteriosclerosis obliterans. 相似文献
58.
H. Noguchi M. Ueda Y. Nakai Y. Iwanaga T. Okitsu H. Nagata Y. Yonekawa N. Kobayashi T. Nakamura H. Wada S. Matsumoto 《American journal of transplantation》2006,6(3):496-504
Islet allotransplantation can achieve insulin independence in patients with type I diabetes. Recent reports show that the two-layer method (TLM), which employs oxygenated perfluorochemical (PFC) and UW solution, is superior to simple cold storage in UW for pancreas preservation in islet transplantation. However, UW solution has several disadvantages, including the inhibition of Liberase activity. In this study, we investigated the features of a new solution, designated M-Kyoto solution. M-Kyoto solution contains trehalose and ulinastatin as distinct components. Trehalose has a cytoprotective effect against stress, and ulinastatin inhibits trypsin. In porcine islet isolation, islet yield was significantly higher in the M-Kyoto/PFC group compared with the UW/PFC group. There was no significant difference in ATP content in the pancreas between the two groups, suggesting that different islet yields are not due to their differences as energy sources. Compared with UW solution, M-Kyoto solution significantly inhibited trypsin activity in the digestion step; moreover, M-Kyoto solution inhibited collagenase digestion less than UW solution. In conclusion, the advantages of M-Kyoto solution are trypsin inhibition and less collagenase inhibition. Based on these data, we now use M-Kyoto solution for clinical islet transplantation from nonheart-beating donor pancreata. 相似文献
59.
60.
D F Lake T Kawamura T Tomiyama W E Robinson Y Matsumoto Y Masuho E M Hersh 《AIDS (London, England)》1992,6(1):17-24
OBJECTIVE: The purpose of this study was to develop and characterize human monoclonal antibodies (HuMAb) that neutralize HIV-1. DESIGN: Based upon previous studies involving the generation of HuMAb that neutralize other enveloped viruses, we thought it feasible to generate HuMAb that might neutralize HIV-1. METHODS: A HuMAb was generated by fusing splenic B-cells from an HIV-positive patient with a mouse myeloma cell line. Flow cytometry was used to determine surface reactivity of the HuMAb on HIV-infected and non-infected cells. Radioimmunoprecipitation was employed to elucidate the antigen recognized by the HuMAb. A cell survival assay was used to determine the ability of the HuMAb to neutralize divergent isolates of HIV-1 in the presence or absence of complement. A gp120-CD4 inhibition enzyme-linked immunosorbent assay (ELISA) was developed in order to initiate studies to determine the mechanism of neutralization by the HuMAb. RESULTS: An anti-HIV HuMAb was generated that neutralized two HIV-1 isolates (IIIB and MN) without complement and which neutralized one divergent isolate (RF) and one clinical isolate in the presence of complement. This HuMAb, designated S1-1, was found, by flow cytometric analysis, to react with the surface of HIV-1-infected but not with uninfected cells. Radioimmunoprecipitation analysis demonstrated that S1-1 binds to native HIV gp120, but not dithiothreitol (DTT)-treated gp120. In addition, HuMAb S1-1 did not bind to denatured HIV antigens in Western blot analysis. HuMAb S1-1 effectively inhibited the binding of gp120 to soluble CD4 in ELISA. CONCLUSIONS: These results suggest that the epitope recognized by S1-1 is conformational and conserved among diverse HIV-1 isolates and may represent an uncharacterized HIV neutralizing domain within or close to the CD4 binding domain on gp120. HuMAb S1-1 might have a role to play in vaccine development or passive immunotherapy. 相似文献