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排序方式: 共有1057条查询结果,搜索用时 15 毫秒
41.
Yoritaka Akimoto Motoaki Sugiura Yukihito Yomogida Carlos Makoto Miyauchi Shiho Miyazawa Ryuta Kawashima 《Human brain mapping》2014,35(4):1167-1178
Verbal irony conveys various emotional messages, from criticism to humor, that differ from the meaning of the actual words. To understand irony, we need conceptual knowledge of irony in addition to an understanding of context. We investigated the neural mechanism of irony comprehension, focusing on two overlooked issues: conceptual knowledge and emotional response. We studied 35 healthy subjects who underwent functional MRI. During the scan, the subject examined first‐person‐view stories describing verbal interactions, some of which included irony directed toward the subject. After MRI, the subject viewed the stories again and rated the degree of irony, humor, and negative emotion evoked by the statements. We identified several key findings about irony comprehension: (1) the right anterior superior temporal gyrus may be responsible for representing social conceptual knowledge of irony, (2) activation in the medial prefrontal cortex and the right anterior inferior temporal gyrus might underlie the understanding of context, (3) modulation of activity in the right amygdala, hippocampus, and parahippocampal gyrus is associated with the degree of irony perceived, and (4) modulation of activity in the right dorsolateral prefrontal cortex varies with the degree of humor perceived. Our results clarified the differential contributions of the neural loci of irony comprehension, enriching our understanding of pragmatic language communication from a social behavior point of view. Hum Brain Mapp 35:1167–1178, 2014. © 2013 Wiley Periodicals, Inc. 相似文献
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43.
Yoh Yamaguchi Masao Hashimoto Susumu Saito Tie Morita Akinari Tsukada Yusaku Kusaba Takashi Katsuno Manabu Suzuki Jin Takasaki Shinyu Izumi Akihiro Matsunaga Yukihito Ishizaka Masayuki Hojo Haruhito Sugiyama 《Internal medicine (Tokyo, Japan)》2022,61(6):913
A 33-year-old woman with a fever, cough, and pharyngitis was admitted after left-sided pleural effusion was detected. The fever and upper respiratory symptoms were confirmed, and she was diagnosed with coronavirus disease (COVID-19) after showing a positive polymerase chain reaction (PCR) test. After thoracentesis, pleural fluid revealed elevated adenosine deaminase values and a positive QuantiFeron test; tuberculous pleurisy was thus suspected. Subsequent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) PCR and anti-SARS-CoV-2 Spike IgG tests were negative, suggesting that the initial PCR result had been erroneous. However, we were unable to confirm this. Data concerning COVID-19 diagnostics are insufficient at present. It is important to make comprehensive judgments regarding the diagnosis and treatment of patients as well as public health. 相似文献
44.
p53-dependent growth arrest of REF52 cells containing newly amplified DNA. 总被引:3,自引:1,他引:3
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Y Ishizaka M V Chernov C M Burns G R Stark 《Proceedings of the National Academy of Sciences of the United States of America》1995,92(8):3224-3228
The rat cell line REF52 is not permissive for gene amplification. Simian virus 40 tumor (T) antigen converts these cells to a permissive state, as do dominant negative mutants of p53, suggesting that the effect of T antigen is due mainly to its ability to bind to p53. To manipulate permissivity, we introduced a temperature-sensitive mutant of T antigen (tsA58) into REF52 cells and selected for resistance to N-(phosphonacetyl)-L-aspartate (PALA). Most freshly isolated PALA-resistant colonies, each of approximately 200 cells, selected at a permissive temperature, arrested when shifted to a nonpermissive temperature. Growth arrest was stable, with no evidence of apoptosis, as long as T antigen was absent but was reversed when T antigen was restored. In contrast, PALA-resistant clones grown to approximately 10(7) cells at a permissive temperature did not arrest when shifted to a nonpermissive temperature. All PALA-resistant clones examined had amplified carbamoyl-phosphate synthetase-aspartate transcarbamoylase-dihydroorotase (CAD) genes, present in structures consistent with a mechanism involving bridge-breakage-fusion (BBF) cycles. We propose that p53-mediated growth arrest operates only early during the complex process of gene amplification, when newly formed PALA-resistant cells contain broken DNA, generated in BBF cycles. During propagation under permissive conditions, the broken DNA ends are healed, and, even though the p53-mediated pathway is still intact at a nonpermissive temperature and the cells contain amplified DNA, they are not arrested in the absence of broken DNA. The data support the hypothesis that BBF cycles are an important mechanism of amplification and that the broken DNA generated in each cycle is a key signal that regulates permissivity for gene amplification. 相似文献
45.
De Keulenaer GW Ushio-Fukai M Yin Q Chung AB Lyons PR Ishizaka N Rengarajan K Taylor WR Alexander RW Griendling KK 《Arteriosclerosis, thrombosis, and vascular biology》2000,20(2):385-391
Monocyte chemoattractant protein-1 (MCP-1) is an important component of the inflammatory response of the vessel wall and has been shown to be regulated by cytokines, such as tumor necrosis factor-alpha (TNF-alpha). However, the precise signaling pathways leading to MCP-1 induction have not been fully elucidated in vascular smooth muscle cells (VSMCs). Cytokine signal transduction involves protein kinases as well as reactive oxygen species (ROS). The relation between these 2 factors is not clear. In this study, we show that TNF-alpha induces a parallel phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) and p38 mitogen-activated protein kinase (p38MAPK) and increases MCP-1 mRNA expression in cultured VSMCs. Inhibition of ERK1/2 but not p38MAPK caused a partial attenuation of MCP-1 induction (43+/-10% inhibition). Incubation of VSMCs with multiple antioxidants (diphenylene iodonium, liposomal superoxide dismutase, catalase, N-acetylcysteine, dimethylthiourea, and pyrrolidine dithiocarbamate) had no effect on TNF-alpha-mediated MCP-1 upregulation. However, simultaneous blockade of the ERK1/2 and ROS pathways by using PD098059 combined with diphenylene iodonium or N-acetylcysteine potently enhanced the ability of MAPK kinase inhibitors to abrogate MCP-1 mRNA expression (100+/-2% inhibition). Thus, parallel ROS-dependent and ERK1/2-dependent pathways converge to regulate TNF-alpha-induced MCP-1 gene expression in VSMCs. These data unmask a complex but organized integration of ROS and protein kinases that mediates cytokine-induced vascular inflammatory gene expression. 相似文献
46.
Sanada M Taguchi A Higashi Y Tsuda M Kodama I Yoshizumi M Ohama K 《Atherosclerosis》2004,176(2):387-392
It is widely believed that the vasculature plays an important role in bone remodeling. We investigated the relationship between forearm endothelial function and bone mass in the lumbar spine in early postmenopausal women without a history of smoking or diabetes mellitus. We studied the forearm resistance artery endothelial function in 110 Japanese women-52 postmenopausal women with normal spinal bone mineral density (BMD), 36 postmenopausal women with osteopenia, and 22 osteoporotic postmenopausal women. Forearm blood flow (FBF) during reactive hyperemia and after sublingual nitroglycerin (NTG) administration was measured by strain-gauge plethysmography. BMD of the lumbar spine (L2-L4) was measured by dual-energy X-ray absorptiometry. After adjustment for age, body mass index, years since the start of menopause, and basal FBF, women with osteoporosis had a lower maximal FBF response to reactive hyperemia (28.4 +/- 3.8 mL/min per 100 mL tissue) than those with normal BMD (39.8 +/- 2.8 mL/min per 100mL tissue) or osteopenia (35.6 +/- 2.5 mL/min per 100mL tissue) (P = 0.029). A significant increase in serum angiotensin-converting enzyme (ACE) activity (P = 0.042) and a significant decrease in the serum concentrations of nitrite/nitrate (P = 0.041) were noted in osteoporotic women compared to women with normal BMD or osteopenia. The present findings suggest that postmenopausal women with low BMD, especially those with osteoporosis, have impaired endothelial function in the forearm resistance arteries. 相似文献
47.
Hideyuki Ishijima Hiroshi Ishizaka Tomio Inoue 《Journal of Medical Imaging and Radiation Oncology》1996,40(1):22-25
The purpose of this study was to evaluate the efficacy of chemical shift gradient echo magnetic resonance imaging (MRI) in distinguishing between cystic teratomas and endometriomas of the ovary, using a 1.5T magnet. The study included 22 patients with 31 ovarian lesions (15 cystic teratomas and 16 endometriomas), which showed high signal intensity on T1-weighted spin echo images. Chemical shift gradient echo images with three different echo times (TE = 2.5, 4.5 and 6.5 ms) were obtained in all cases. Indices were calculated on the basis of the signal intensities of lesions on the chemical shift gradient echo images. All endometriomas had signal intensity indices of less than 2.1, while all cystic teratomas had signal intensity indices of 18.1 or greater. Chemical shift gradient echo imaging is an alternative method that is useful and simple for distinguishing between cystic teratomas and endometriomas of the ovary. 相似文献
48.
Treatment of 2019 cases with upper urinary tract calculi using a piezoelectric lithotriptor ESL-500A
Matsuoka Y Ishizaka K Machida T Kobayashi T Oka K 《Nihon Hinyōkika Gakkai zasshi. The japanese journal of urology》2002,93(3):476-482
PURPOSE: We evaluated the results of extracorporeal shock wave lithotripsy (ESWL) in a large number of cases with upper urinary tract calculi, and reported the strategy how to improve the efficacy and safety of ESWL. PATIENTS AND METHOD: Eight hundred fifteen patients with renal calculi and 1,204 patients with ureteral calculi were treated using a piezoelectric ultrasound-guided lithotriptor, Toshiba ESL-500A. Auxiliary measures were needed in 51 cases (2.5%) and 1,968 cases (97.5%) were treated by in situ procedures. ESWL was performed with the optimal positioning of the patient and under the continuous monitoring by ultrasound system. The visibility of stones was improved by removal of abdominal gas and administration of diuretic agent to dilate the ureter. Cases with urinary tract infection were medicated by antibiotics and the obstruction of the urinary tract was cleared away as soon as possible. RESULTS: Including the cases with residual fragments less than 4 mm, the success rates at one month after the treatment were 97.7% and 98.7% for the renal and ureteral calculi, respectively. The mean numbers of sessions were 1.49 for renal calculi and 1.16 for ureteral calculi. Multiple sessions were required in 24.2% of renal calculi and 12.0% of ureteral calculi. No serious complication has been observed except for three cases, which were sepsis after ESWL, anuria in a solitary kidney, and pyonephrosis caused by Steinstrasse with urinary infection, respectively. CONCLUSION: ESWL using ESL-500A is an efficient treatment of upper urinary tract calculi which has higher pulverization rate and fewer complications in the adequate procedure. 相似文献
49.
50.
Bone mineral density in hypogonadal men remains low after long—term testosterone replacement 总被引:3,自引:0,他引:3
AIM: In 11 congenital hypogonadal men, the bone mineral density (BMD) values were determined to assess the effect of long-term androgen replacement therapy (ART) on skeletal integrity. METHODS: Eleven congenital hypogonadal men, including 8 isolated gonadotropin deficiency patients, 2 Kallmann's syndrome and 1 vanishing testes syndrome were recruited and treated with 250 mg of testosterone enanthate intramuscularly every 4 weeks for 7-43 years (mean+/-SD: 21.5 +/-13 years). In these patients and a group of 10 healthy young men (controls), the whole and trabecular BMDs were examined at the distal end of radius by means of a peripheral quantitative computerized tomography device. RESULTS: The whole radial BMD in hypogonadal men was significantly less in the patients than in the healthy men (498+/-115 and 725+/-134 mg/cm(3), respectively; P<0.01); the trabecular BMD was also lower in the hypogonadal men (199+/-80 and 375+/-89 mg/cm(3); P< 0.01). The whole radial BMD values in 10 of 11 hypogonadal men were at least 1 SD below the mean value for healthy young men; 2 hypogonadal men had BMD values more than 2.5 SD lower than the healthy mean. Additionally, the whole radial BMD showed a significant negative correlation with the patient's age at the initiation of ART (r = 0.748, P<0.01). The serum level of bone-specific alkaline phosphatase and the urinary level of deoxypyridinoline were not significantly different between the two groups. CONCLUSION: Osteopenia persists in the hypogonadal men after long-term ART, suggesting that such patients have a persistent defect in bone development not alleviated by androgen replacement. 相似文献