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61.
Sasaki J Sugawara K Tanno Y 《Shinrigaku kenkyu : The Japanese journal of psychology》2005,76(5):445-452
The aim of the present study is to explain why there is "the diverse U letter relationship" between embarrassment and psychological distance empirically, in view of Schlenker and Leary (1982)'s self-presentation model of social anxiety. In Study 1, those relationships were observed in three different situations. In Study 2, the main effect of motivation for avoiding rejection and the damage of self-image, and their interaction with embarrassment was examined by hierarchical regression analysis. In the first step, the psychological distance, in the second step, the main effect of both, and in the third step, the interaction was entered. As a result, in the second step, both main effects were significant, but in the third step, only interaction was significant, and both main effects were not significant. This showed that the interaction could predict embarrassment, although the psychological distance was controlled. Finally, this result was discussed in view of social norm. 相似文献
62.
In vivo labeling of amyloid with BF-108 总被引:3,自引:0,他引:3
Suemoto T Okamura N Shiomitsu T Suzuki M Shimadzu H Akatsu H Yamamoto T Kudo Y Sawada T 《Neuroscience research》2004,48(1):65-74
Detection of aggregated amyloid-beta (Abeta) with a non-invasive imaging modality such as positron emission tomography (PET) was suggested to be ideal for the diagnosis of Alzheimer's disease (AD) prior to the onset of clinical symptoms. We have been searching for imaging probe candidates with a high affinity for aggregated Abeta in vitro and in vivo and high lipophilicity, a characteristic that allows for the permeation of the blood-brain barrier (BBB). As analyzed by Thioflavin T (ThT) assay and octanol/water partition coefficient test (PC), 3-diethylamino-6-(2-fluoroethyl)ethylaminoacridine (BF-108) were found to have high affinity for Abeta aggregates in vitro and high lipophilicity. Intravenously administrated BF-108 labeled Abeta aggregates injected into the amygdala as observed under a fluorescence microscope, showing this compound's permeability of BBB and an ability to label Abeta in vivo. BF-108 also labeled neuritic senile plaques (SPs), neurofibrillary tangles, and amyloid-laden vessels in temporal and hippocampal sections from AD patients. Following intravenous administration of BF-108 to an APP23 transgenic (TG) mouse, in vivo labeling of endogenous plaques was seen in brain sections by fluorescence microscopy. These properties suggest the potential utility of BF-108 for in vivo imaging of AD pathology. 相似文献
63.
The critical role of ocular-infiltrating macrophages in the development of choroidal neovascularization 总被引:9,自引:0,他引:9
Tsutsumi C Sonoda KH Egashira K Qiao H Hisatomi T Nakao S Ishibashi M Charo IF Sakamoto T Murata T Ishibashi T 《Journal of leukocyte biology》2003,74(1):25-32
Choroidal neovascularization (CNV) is directly related to visual loss in some eye diseases, such as age-related macular degeneration. Although several human histological studies have suggested the participation of macrophages in CNV formation, the precise mechanisms are still not fully understood. In this study, we elucidated the role of ocular-infiltrating macrophages in experimental CNV using CCR2 knockout (KO) mice, wild-type mice, and C57BL/6 (B6) mice. CCR2 is the receptor of monocyte chemoattractant protein-1, and the number of infiltrating macrophage and the area of CNV were significantly reduced in CCR2 KO mice. Enriched ocular-infiltrating macrophages from B6 mice actually showed angiogenic ability in a dorsal air sac assay. Moreover, their expression of class II, CD40, B7-1 and B7-2 molecules, and the mRNA for potential angiogenic factors, such as vascular endothelial growth factor, basic fibroblast growth factor, and tumor necrosis factor alpha, was also observed. Collectively, we conclude that ocular-infiltrating macrophages play an important role in CNV generation. 相似文献
64.
We examined the action of high (2×10–8M) and low (6×10–9M) concentrations of atrial natriuretic factor (ANF) on water and urea transport in the rat inner medullary collecting duct (IMCD) using the in vitro microperfusion technique. We measured the hydraulic conductivity (Lp ×10–6 cm/atm per second) and both lumen-to-bath (P
u(lb)) and bath-to-lumen (P
u(bl)) 14C-urea permeabilities (P
u× 10–5 cm/s) in the absence and in the presence of vasopressin (VP). High concentrations of ANF were able to inhibit the maximum activity of (50 U/ml) VP-stimulated L
p but physiological concentration of ANF inhibit only submaximum activity (10 U/ml) of VP-stimulated L
p. The hydrosmotic effect of dibutyryl-cyclic 3,5 adenosine monophosphate (cAMP) (10–4M) was unchanged by high concentrations of ANF (2×10–8M). Also we found that high (10–4M) and low (10–6M) concentrations of exogenous cyclic 3,5-guanosine monophosphate (GMP) while unable to change the Lp in the absence of VP, decreased the maximum activity of VP-stimulated Lp significantly. We also found that ANF inhibits partially and in a reversible manner the VP-stimulated P
u(lb) but not the VP-stimulated P
u(bl). These results demonstrated that plasma concentrations of ANF observed during volume expansion (10–10M) are able to inhibit submaximum activity of VP-stimulated (10 U/ml) L
p in the rat IMCD, this effect seems to occur before cAMP formation and it appears to be mediated by cGMP. ANF (6× 10–9M) also reduced the VP-stimulated urea outflux. Therefore, the increase in water excretion produced by ANF could be explained, at least in part, by the inhibition by ANF of vasopressin effects on water and urea transport in the IMCD.This study was presented in part at the VI Latin American Congress of Nephrology, Brazil, October 1985 and at the Xth International Congress of Nephrology, London, July 1987. 相似文献
65.
Yoshitake Hayashi Fumihito Kikuchi Teruaki Oka Shinji Itoyama Noboru Mohri Kensuke Usuki Fumimaro Takaku Tohru Murakami Yoshimi Saitoh Yoshinori Urano 《Pathology international》1988,38(6):789-798
Rhabdomyosarcoma manifested as a systemic disease is very rare and cases showing diffuse metastasis in the bone marrow are most unusual. Recently we encountered two cases of rhabdomyosarcoma with diffuse bone marrow metastasis which were clinically manifested as acute leukemia. The first patient was a 15-year-old female, who was admitted in 1982 with pancytopenia and many large primitive cells in bone marrow aspirates, hematological malignancy being diagnosed. Thereafter the bilateral breasts showed rapid swelling and a biopsy specimen revealed the histological features of typical alveolar rhabdomyosarcoma. The primary site of the neoplasm remained undetermined during the course. At autopsy, it was disclosed that the neoplasm originated from the left thigh and showed generalized metastasis. The second patient was a 38-year-old man, who was admitted in 1986 because of a nasal polyp obstructing the nasal cavity, and persistent nasal bleeding. Peripheral blood samples showed leucoerythroblastosis and thrombocytopenia, and large primitive cells were found In bone marrow aspirates, so that hematological malignancy was initially diagnosed. A biopsy specimen of the nasal polyp showed proliferation of large round cells and electron microscopy demonstrated the ultrastructural features of rhabdomyosarcoma. 相似文献
66.
Suzuki N Kudo K Sano Y Ito K 《International archives of allergy and immunology》2001,124(1-3):113-116
It is generally considered that tuberculosis (TB) is a disease which upregulates Th1 cell function. There is a hypothesis that infection of Mycobacterium tuberculosis may prevent allergic disorders such as bronchial asthma. However, our clinical experience of patients with TB somewhat conflicts this hypothesis. Hence, we investigated Th1/Th2 balance in the peripheral blood of patients with active TB by measuring serum levels of IgE antibody and by intracellular cytokine assay. We found that serum levels of IgE in the patients with active TB were significantly higher than in those with lung cancer or with COPD. In the TB patients, titers of IgE tended to correlate with disease severity. Intracellular cytokine assay demonstrated that IFN-gamma-positive cells were significantly decreased in the patients with active TB compared to normal controls. The ratio of IFN-gamma-positive (Th1-like)/IL-4-positive (Th2-like) cells was remarkably reduced in the TB patients (p < 0.0001). This ratio showed a significant negative correlation with erythrocyte sedimentation rate and with C-reactive protein. Therapy against TB for 2-3 months did not result in significant changes of the Th1/Th2 ratio. These findings suggest that infection of M. tuberculosis does not systematically upregulate Th1 cells in some patients, and is unlikely to prevent allergic disorders like asthma. 相似文献
67.
Motoshige Kudo Masakuni Shimizu Yasuhiko Akutsu Hisatoshi Lrnaya Mau Nan Chen Myota Miura 《Pathology international》1990,40(1):50-56
A case of cerebellar medulloblastoma with clusters of mature ganglion cells and glial cells is described. The patient, a 15 -year -old girl, underwent three operations followed each time by radiation and chemotherapy during the four-year clinical course. Histologically, the ganglion cells were clearly identifiable by their abundant eosino-philic cytoplasm, round nuclei with prominent nucleoli, tigroid granules, and argyrophilic fibrils and axons. Im-munohistochemically, the cells were NSE- and NF positive, and ultrastructurally they contained abundant tubules and filaments, neurosecretory granules and well developed rough endoplasmic reticulum. There were many cells transitional in appearance between primitive cells and mature ganglion cells. The tumor also had many mature yet atypical astrocytes and oligodendrocytes. The exact mechanism of the extensive neuronal and glial maturation of medulloblastoma cells is unclear, but the repetitive surgical interventions, radiation and chemotherapy might have had certain cytostatic effects on rapidly dividing medulloblastoma cells, giving them a chance to mature into postmitotic cells with potential for neuronal and glial differentiation. Acta Pathol Jpn 40: 50–56, 1990. 相似文献
68.
General anesthetics modulate autonomic nervous system function including thermoregulatory control, which resides in the preoptic area of the anterior hypothalamus. However, the mechanism by which anesthetics modulate hypothalamic function remains unknown. We hypothesized that isoflurane increases norepinephrine release in the preoptic area and in the posterior hypothalamus causing hypothermia during anesthesia. To test this hypothesis, we performed a series of in vivo and in vitro studies in rats. In vivo studies: 1) Norepinephrine release was measured by microdialysis in the preoptic area or the posterior hypothalamus (n=9 each) before, during (30 min), and after (50 min) rats were anesthetized with 2% isoflurane. 2) In five rats, blood gases and arterial pressure were measured. 3) Body temperature changes (n=6 each) were measured after prazosin (0, 0.05, 0.5 microg), norepinephrine (0, 0.1, 1.0 microg), or 0.5 microg prazosin with 1.0 microg norepinephrine injection into the preoptic area. In vitro study: Norepinephrine release was measured from anterior or posterior hypothalamic slices (n=10 each) incubated with 0, 1, 2, or 4% isoflurane in Ca2+-containing buffer or with 4% isoflurane (n=10) in Ca2+-free buffer. Data were analyzed with repeated measures or factorial ANOVA and Student-Newman-Keuls tests. P<0.05 was significant. During anesthesia, norepinephrine release in the preoptic area was increased approximately 270%, whereas the release in the posterior hypothalamus remained unchanged. During emergence, posterior hypothalamic norepinephrine release increased by approximately 250% (P<0.05). Rectal temperature changes correlated with norepinephrine release from the preoptic area. Norepinephrine in the preoptic area enhanced isoflurane-induced hypothermia, while prazosin reversed it. Norepinephrine release from anterior hypothalamic slices increased at all isoflurane concentrations, but only at the highest concentration in posterior hypothalamic slices. Under Ca2+-free conditions, 4% isoflurane increased norepinephrine from both regions. These results suggest that augmentation of norepinephrine release in the preoptic area is responsible for hypothermia during general anesthesia. 相似文献
69.
Okamura A Yazawa S Nishimura T Tanaka S Takai I Kudo S Asao T Kuwano H Matta KL Akamatsu S Kochibe N 《Clinical & experimental metastasis》2000,18(1):37-43
A new ex vivo method for assaying adhesion of cancer cells to the greater omentum has been developed using mouse greater omentum and [3H]labelled human gastric and mouse colorectal cancer cells. Since the adhesion rates were found to increase up to 18 h and labelled cells seemed to be stable during the period, the present method could be useful for investigating adhesion of cancer cells to the greater omentum, which must occur at the first step of the peritoneal dissemination. The adhesion of cancer cells to the greater omentum was inhibited by a series of chemically synthesized oligosaccharides and Galβ1,3[3OMeGalβ1,4GlcNAcβ1,6]αBn was found to be the best inhibitor. The anti-tumor effect of this novel tetrasaccharide in vivo was shown in preliminary experiments using Balb/c mice and colon26 cells. 相似文献
70.