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排序方式: 共有3963条查询结果,搜索用时 15 毫秒
81.
Mamoru Takahashi Yasuo Takehara Kenji Fujisaki Tomoyuki Okuaki Yukiko Fukuma Norihiro Tooyama Katsutoshi Ichijo Tomoyasu Amano Satoshi Goshima and Shinji Naganawa 《Magnetic resonance in medical sciences》2021,20(4):359
PurposeNon-calcified cholesterol stones that are small in size are hard to be depicted on CT or magnetic resonance cholangiopancreatography. This institutional review board (IRB)-approved retrospective in vitro study aims to characterize contrast behaviors of 3 main components of the gallstones, i.e., cholesterol component (CC), bilirubin calcium component (BC) and CaCO3 (CO) on 3D radial scan with ultrashort TE (UTE) MRI, and to test the capability of depicting CC of gallstones as bright signals as compared to background saline.MethodsFourteen representative gallstones from 14 patients, including 15 CC, 6 BC and 4 CO, were enrolled. The gallstones underwent MRI including fat-saturated T1-weighted image (fs-T1WI) and UTE MRI with dual echoes. The contrast-to-noise ratio (CNR) and the chemical analysis for the 25 portions of the stones were compared.ResultsBC was bright on fs-T1WI, which did not change dramatically on UTE MRI and the signal did not remain on UTE subtraction image between dual echoes. Whereas the CC was negative or faintly positive signal on fs-T1WI, bright signal on UTE MRI and the contrast remained even higher on the UTE subtraction, which reflected their short T2 values. Median CNRs and standard errors of the segments on each imaging were as follows: on fs-T1WI, −10.2 ± 4.2 for CC, 149.7 ± 27.6 for BC and 37.9 ± 14.3 for CO; on UTE MRI first echo, 16.7 ± 3.3 for CC, 74.9 ± 21.3 for BC and 17.7 ± 8.4 for CO; on UTE subtraction image, 30.2 ±2.0 for CC, −11.2 ± 5.4 for BC and 17.8 ± 10.7 for CO. Linear correlations between CNRs and cholesterol concentrations were observed on fs-T1WI with r = −0.885, (P < 0.0001), UTE MRI first echo r = −0.524 (P = 0.0072) and UTE subtraction with r = 0.598 (P = 0.0016).ConclusionUTE MRI and UTE subtraction can depict CC bright. 相似文献
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Kyoko Itoh Takashi Kasai Yukiko Tsuji Kozo Saito Ikuko Mizuta Yoshinori Harada Shinji Sudoh Toshiki Mizuno Masanori Nakagawa Shinji Fushiki 《Neuropathology》2014,34(3):309-313
Multiple system atrophy (MSA) is an oligodendrogliopathy of presumably sporadic origin, characterized by prominent α‐synuclein inclusions with neuronal multisystem degeneration, although a few Mendelian pedigrees have been reported. Here we report two familial cases of MSA of unknown genetic background. One patient was diagnosed as a possible MSA‐C (cerebellar dysfuntion) case, and the other as clinically possible MSA‐P (parkinsonism), which turned out to be definite MSA, based on a detailed autopsy. The neuropathology showed extensive deposition of α‐synuclein in the glia as well as in the neurons located in the cerebral cortices and hippocampal systems, although neither multiplication of the SNCA gene or mutations in COQ2 gene were identified in the family concerned. 相似文献
86.
Yamashita H Ohno K Amada Y Hattori H Ozawa-Funatsu Y Toya T Inami H Shishikura J Sakamoto S Okada M Yamaguchi T 《The Journal of pharmacology and experimental therapeutics》2004,308(1):127-133
The anticonvulsant activity of 2-[N-(4-chlorophenyl)-N-methylamino]-4H-pyrido[3.2-e]-1,3-thiazin-4-one (YM928), a novel alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor antagonist, was studied in animal models of generalized seizure. YM928 exerted significant anticonvulsant effects in the maximal electroshock (MES) seizure test (ED50 = 7.4 mg/kg p.o.), pentylenetetrazol (PTZ)-induced seizure test (ED50 = 9.6 mg/kg p.o.), AMPA-induced seizure test (ED50 = 5.5 mg/kg p.o.), and strychnine-induced seizure test (ED50 = 14.0 mg/kg p.o.) in mice. Effects in rats were detected in the MES seizure test (ED50 = 4.0 mg/kg p.o.) and PTZ-induced seizure test (ED50 = 6.2 mg/kg p.o.). The profile of YM928 was compared with that of established antiepileptics. Valproate showed beneficial effects in all tests used. In contrast, carbamazepine, phenytoin, lamotrigine, phenobarbital, diazepam, ethosuximide, and gabapentin were not active against seizures induced by at least one stimulant. In the rotarod test, YM928 impaired motor coordination (TD50 = 22.5 mg/kg p.o.). The protective index (TD50 value of the rotarod test/ED50 value of MES seizure) was 3.0, suggesting that YM928 can exert antiepileptic effects with only minor motor disturbances. YM928 at doses of 2, 4, and 8 mg/kg p.o. did not significantly affect the threshold of electroshock seizure in rats after 16 days of repeated administration. These data indicate that YM928 does not induce tolerance after subchronic administration. These results indicate that YM928 is a broad-spectrum anticonvulsant that would prove useful for the treatment of generalized seizure in human epileptic patients. 相似文献
87.
Yukiko Kanno Masashi Watanabe Taichi Kimura Katsuya Nonomura Shinya Tanaka Shigetsugu Hatakeyama 《Acta histochemica》2014
Tripartite motif protein 29 (TRIM29) is one of the TRIM family proteins, some of which function as E3 ubiquitin ligases. In this study, we investigated the usefulness of TRIM29 for diagnosis of prostate cancer. Prostate tissues including carcinoma and non-carcinoma tissues obtained by needle biopsy and radical prostatectomy were used. Immunohistochemistry was performed according to standard procedures using an antibody against TRIM29. Immunohistochemical staining with an antibody against 34βE12, which recognizes cytokeratins 1, 5, 10 and 14, was performed as a control. Basal cells of normal prostatic glands were stained with anti-TRIM29 antibody in all cases, whereas prostate cancer tissues had no or little staining with anti-TRIM29 antibody. TRIM29 is selectively expressed in basal cells of the normal prostate gland, and immunohistochemical staining with anti-TRIM29 antibody showed the same expression pattern as that with 34βE12 in prostate cancer and its benign mimics. Our data indicate that TRIM29 may be useful for distinguishing prostate cancers from benign tissues. 相似文献
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89.
Nobuhiko Uchida Yasuo Shimizu Mio Fujimaki Yasuhiro Horibata Yusuke Nakamura Yukiko Horigane Kazuyuki Chibana Akihiro Takemasa Hiroyuki Sugimoto Seiji Niho 《Journal of Clinical Biochemistry and Nutrition》2022,70(2):108
Metabolic alteration is increasingly recognized as an important pathogenic process that underlies fibrosis across many organ types, and metabolically targeted therapies could become important strategies for reducing fibrosis. In present study, target enzymes that are involved in changes in phospholipid metabolism during fibroblast-to-myofibroblast transition induced by transforming growth factor beta 1 (TGF-β1) were examined. Different amounts of phospholipids were found in the 2 groups. In response to TGF-β1 stimulation, 17 lipids decreased and 17 increased. The latter included the phospholipids phosphatidylcholine (PC), phosphatidylserine (PS), and phosphatidylethanolamine (PE). Furthermore, among the rate-limiting enzymes that regulate these phospholipids, phosphatidylserine decarboxylase (PISD), which controls conversion of PS to PE and is localized in mitochondria, decreased in response to TGF-β1. Knockdown of PISD alone without TGF-β1 stimulation increased expression of α-smooth muscle actin mRNA and production of total collagen. Taken together, these results indicate that PISD is involved in the mechanism of fibrogenesis by regulating phospholipid metabolism. 相似文献
90.
Yukiko Matsuda Tsuneyasu Terauchi Kota Murahira Seema Patil Vajendra Joshi Kazuyuki Araki Akira Taguchi Tomohiro Okano 《Oral Radiology》2014,30(1):20-26