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1.
Synaptic contacts between growth hormone-releasing hormone (GHRH)- and somatostatin-containing neurons were demonstrated in the rat hypothalamus by a double-staining immunocytochemical method at the electron microscopic level. Somatostatin-immunoreactive nerve terminals synapse on GHRH-positive dendrites and cell bodies in the arcuate nucleus. A fine network of GHRH-immunopositive nerve terminals was observed at the light microscopic level in the rostral part of the periventricular nucleus and in the dorsal part of the arcuate nucleus around somatostatin-containing neuronal elements. With the electron microscope synaptic contact between GHRH-containing nerve terminals and somatostatin-containing dendrites are demonstrated. The reciprocal innervation between GHRH- and somatostatin-containing neurons that project to the median eminence and regulate growth hormone secretion must allow them to coordinate their activities. 相似文献
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3.
Makiho Sekiuchi Kimimasa Nakabayashi Tomohumi Marumo Yoshihiro Arimura Akira Yamada 《Ryūmachi》2003,43(4):696-702
A 65-year old female, who had been suffered from rheumatoid arthritis, was admitted to our hospital because of fever, oral ulcers, perianal skin ulcers, petechiae in the both legs, hepatosplenomegaly and cervical lymphadenopathy. Her laboratory data showed severe anemia, leukocytopenia, and thrombocytopenia as well as low PT activity, prolonged APTT, decreased fibrinegen and elevated FDP. In addition to raised values of liver enzymes and triglyceride, marked elevation of several cytokines were found. IgM and IgG class antibodies to cytomegalovirus were demonstrated positive and their titers were 2.60 and 938.0, respectively. The study for the aspiration of bone marrow revealed hemophagocytosis of erythrocytes, leukocytes and thrombocytes. Based upon these findings, she was diagnosed as having hemophagocytic syndrome associated with cytomegalovirus infection. Steroid treatment inducing mini-pulse therapy was introduced to her and bought full recovery from the illness. The association of hemophagocytic syndrome to rheumatoid arthritis was reviewed in the literature and five cases were documented to have good prognosis with steroid treatment. 相似文献
4.
Hisashi Masugata Shoichi Senda Fuminori Goda Yumiko Yoshihara Kay Yoshikawa Norihiro Fujita Hiroyuki Daikuhara Hiroyuki Nakamura Teruhisa Taoka Masakazu Kohno 《Hypertension research》2006,29(11):897-903
The purpose of the present study was to elucidate the cardiac structure and function in patients who have metabolic syndrome but no history of cardiovascular disease by analyzing echocardiographic findings. Echocardiographic examination was performed to screen for cardiovascular disease in 135 patients who were in their sixties. Patients were divided into metabolic syndrome (n=65, age: 65+/-2.7 years) and non-metabolic syndrome (n=70, age: 66+/-2.5 years) groups based on the criteria for metabolic syndrome proposed by the Japanese Society of Hypertension and seven other societies in 2005. The left ventricular (LV) wall thickness and dimension were measured by M-mode echocardiography. The relative wall thickness, LV mass index, and LV ejection fraction (LVEF) were calculated. LV diastolic function was assessed by the peak velocity of early rapid filling (E velocity) and the peak velocity of atrial filling (A velocity), and the ratio of E to A (E/A) was assessed by the transmitral flow. The Tei index, which reflects both LV diastolic and systolic function, was also calculated. There were no differences in relative wall thickness, LV mass index, or LVEF between the two groups. However, both the EIA and Tei index were significantly different between the metabolic syndrome (0.66+/-0.14 and 0.36+/-0.07, respectively) and non-metabolic syndrome (0.88+/-0.25 and 0.29+/-0.09) groups (p<0.001). These results indicate that patients with metabolic syndrome can have cardiac diastolic dysfunction even if they have neither LV hypertrophy nor systolic dysfunction. 相似文献
5.
Yumiko Motoi Masashi Takanashi Masako Itaya Kazuhiko Ikeda Yoshikuni Mizuno Hideo Mori 《Neuropathology》2004,24(1):60-65
In the present case, a patient in whom limb apraxia and asymmetrical parkinsonism developed suggesting corticobasal degeneration, is reported. Neuropathologic examination revealed numerous tufted astrocytes in the precentral cortex in addition to the characteristic pathologic findings of PSP. Therefore, on the basis of clinicopathologic features, atypical progressive supranuclear palsy was diagnosed. In addition, the brain tissue of the present patient was investigated with an antibody specific for four‐repeat tau (4R‐tau). In the precentral cortex, numerous tau‐positive tufted astrocytes, pretangles, and threads were positive for 4R‐tau. Using a confocal microscopy we demonstrated that tufted astrocytes positive for 4R‐tau were adjacent to astrocytes positive for GFAP. The present findings suggest that accumulation of four‐repeat tau in astrocytes is a degenerative process rather than a reactive process. 相似文献
6.
A 47-year-old woman visited a clinic with dyspnea which had continued for two months and was followed by general fatigue and fever. Antibiotics were not effective. Edematous erythema occurred on her face, elbows, knees and feet, and she entered our hospital. A skin biopsy revealed interface dermatitis with severe edema and mucinosis in dermis. Diffuse bilateral infiltration was observed in the chest X-ray, and laboratory findings showed increased LDH, GPT, GOT and CPK. No antinuclear factor was detected. Her respiratory condition rapidly worsened, and she died eight days after hospitalization in spite of corticosteroid pulse therapy. The autopsy revealed that the main cause of death was diffuse alveolar damage (DAD). Interstitial pneumonia related to dermatomyositis is not histologically uniform; the response to the therapy depends on its histological type. The patients with dermatomyositis who have poor prognosis are clinically characterized by acute onset with general symptoms and less pronounced muscle weakness; they generally show DAD in their lungs. We need to establish a simple method for distinguishing histological types of interstitial pneumonia and adequate therapy for each one. 相似文献
7.
Nishioka K Okano M Ichihara Y Ichihara N Nishizaki K 《International archives of allergy and immunology》2005,136(2):142-147
BACKGROUND: Exposure to acute stressors modulates both innate and acquired immune function. However, little is known about whether stress has the potential to modulate the pathogenesis of allergic rhinitis. OBJECTIVES: To determine the effects of acute restraint stress on the initiation of allergic rhinitis in a murine model. METHODS: CBA/J mice were repeatedly intranasally sensitized with phospholipase A2 (PLA2) from honeybee venom without adjuvant. Restraint stress was applied using uniform cylinders once a week for a continuous 8-hour period, on five occasions in total. Production of PLA2-specific antibodies and degree of nasal and blood eosinophilia were compared between stressed and control mice. RESULTS: Repeated intranasal sensitization with PLA2 induced PLA2-specific IgE and marked eosinophilia in both the nose and blood in CBA/J mice. Exposure to restraint stress significantly inhibited production of PLA2-specific IgE, IgG1 and IgG2a. Conversely, the stress exerted no significant effect on eosinophilia. CONCLUSIONS: Exposure to acute restraint stress inhibits antigen-specific antibody production, but not local or systemic eosinophilia. The results of this study suggest that acute stress has the potential to modulate the initiation of allergic rhinitis. 相似文献
8.
Stromal-derived factor-1alpha/CXCL12-CXCR 4 axis is involved in the dissemination of NSCLC cells into pleural space 总被引:2,自引:0,他引:2
Oonakahara K Matsuyama W Higashimoto I Kawabata M Arimura K Osame M 《American journal of respiratory cell and molecular biology》2004,30(5):671-677
Malignant pleural effusion (PE) is one of the poor prognostic factors in non-small cell lung cancer (NSCLC), and the detailed mechanism of the malignant PE formation is not fully elucidated. Recently, CXCR4, a receptor for chemokine stromal-derived factor-1alpha (SDF-1alpha) that can induce chemotaxis of cells, was reported to be expressed on NSCLC. In this study, we hypothesized that the SDF-1alpha/CXCR4 axis may be involved in the dissemination of malignant cells into pleural space, and investigated its expression, function, and signaling pathway using NSCLC cell lines and clinical samples from 43 patients with NSCLC with malignant PE. We found functional expression of CXCR4 on NSCLC cell lines, and also found that SDF-1alpha could induce migration via phosphatidylinositol 3 (PI-3) kinase- and p44/42 mitogen-activated protein kinase-dependent manner. The SDF-1alpha levels in malignant PE were significantly higher than those in transudate PE and showed a significant positive correlation with PE volumes. The sensitivity and specificity for prediction of recurrence of malignant PE was 61.5% and 83.3%, respectively (cutoff SDF-1alpha = 2,500 ng/ml), and better than those using pH of PE. Cancer cells in malignant PE expressed CXCR4, and mesothelial cells of the pleura stained positive for SDF-1alpha. The SDF-1alpha/CXCR4 axis is involved in the dissemination of NSCLC cells into pleural space. 相似文献
9.
Different immunosuppresive effects of anti-red blood cell sera and their fractions obtained from various animal species 下载免费PDF全文
Sheep red cells (RC) were coupled with HSA by means of an HSA—anti-SRBC IgG conjugate. The coupled RC were used to prepare rosettes with spleen cells of mice immunized to HSA in Freund's complete adjuvant. The rosettes were fractionated on discontinuous Ficoll gradients and the rosette-rich and rosette-poor fractions were tested for ability to transfer adoptively secondary responsiveness to HSA. Efficiency of transfer was measured in terms of haemagglutination titres. Memory of HSA was shown to be associated with rosette-forming cells, i.e. with cells carrying receptors for HSA. Several parameters of the adoptive transfer system employed were studied. The HSA-coupled RC proved to be very efficient in stimulating secondary responses to HSA. High titres of haemagglutinating antibodies (up to 1/80,000) were obtained with 10 × 106 spleen cells transferred and 2 × 106 spleen cells consistently gave titres of the order of 1/10,000. 相似文献
10.
Suppressive effects of receptive field surround on neuronal activity in the cat primary visual cortex 总被引:1,自引:0,他引:1
Effects of sinusoidal grating stimulus presented outside the classical receptive field (CRF) on neuronal responses were studied in the primary visual cortex of anaesthetized cats. Among 101 cells electrophysiologically recorded, the predominant effect of the stimulus in the receptive field surround (SRF) was the suppression of responses to the CRF stimulation, and the SRF grating suppressed them up to 56% of the responses (44% suppression) to the CRF stimulus alone. The strong suppression was observed more often in layer II/III cells than in other layers and in complex cells more often than in simple cells. The modulatory effects by SRF stimulus might be enhanced by the cortical recurrent excitation particularly in the superficial layers. We also examined whether the modulation by the surround grating exhibits a differential effect according to the presence or absence of figure-ground segregation in the stimulus configuration. For this purpose, effects of stimulus configuration with orientation-, direction-contrast or relative spatial phase difference between CRF and SRF stimuli (figure-ground segregated configuration) were compared with those of uniform configuration of stimulus (non-segregated configuration). There was a population of cells, which exhibited significantly stronger suppression with non-segregated configuration than with figure-ground segregated configuration. Such differential modulation of response by the SRF stimulus in the primary visual cortex is a possible basis of perceptual figure-ground segregation. 相似文献