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91.
Takaki M Ueda Y Doi T Nagatomo K Murashima YL Nakajima A Kannan H 《Neuroscience research》2007,58(3):336-338
Electron spin resonance (ESR) spectroscopy combined with in vivo microdialysis was used to analyze the antioxidant ability in the hippocampus of mice in an interictal state of EL mice utilizing decay ratio of an exogenously applied nitroxide radical (3-methoxycarbonyl-2,2,5,5-tetramethylpyrrolidine-1-oxyl (PCAM)). In EL mice with a history of frequent seizures, the half-life of the electron paramagnetism of PCAM in the hippocampus was prolonged. These results revealed decreased antioxidant ability, suggesting vulnerability against oxidative stress. Our data suggest that epileptogenesis in EL mice with chronic seizures is associated with functional failure due to the oxidized redox state and revealed that the decreased hippocampal antioxidant ability is related to the regional vulnerability to oxidative stress in the limbic system of EL mice during epileptogenesis. 相似文献
92.
In three-dimensional irradiation with pencil beam scanning, an extra dose is inevitably delivered to the irradiated site due to the finite reaction times of the beam delivery system, and it causes a severe distortion of the dose distribution in the target region. Since the amount of the extra dose is proportional to the beam intensity, the dose uniformity deteriorates as the beam intensity is increased in order to shorten the treatment time. In order to overcome this problem and shorten the treatment time, we have developed an optimization method in which the extra dose is integrated into the optimization process of the best weighting matrix. The effectiveness and applicability of the optimization method for spot and raster scanning irradiation were confirmed with computer simulations and also confirmed using irradiation experiments for spot scanning irradiation. The treatment time could be shortened to about one sixth of the time needed without taking the extra dose into account while obtaining the same degree of dose homogeneity in the target volume. A typical treatment time with the proposed method is about 15 s for the irradiation of a spherical target with an 80 mm diameter at 3 GyE. 相似文献
93.
Inaniwa T Kohno T Yamagata F Tomitani T Sato S Kanazawa M Kanai T Urakabe E 《Medical physics》2007,34(5):1684-1692
In proton therapy, it is important to evaluate the field irradiated with protons and the deposited dose distribution in a patient's body. Positron emitters generated through fragmentation reactions of target nuclei can be used for this purpose. By detecting the annihilation gamma rays from the positron emitters, the annihilation gamma ray distribution can be obtained which has information about the quantities essential to proton therapy. In this study, we performed irradiation experiments with mono-energetic proton beams of 160 MeV and the spread-out Bragg peak beams to three kinds of targets. The annihilation events were detected with a positron camera for 500 s after the irradiation and the annihilation gamma ray distributions were obtained. In order to evaluate the range and the position of distal and proximal edges of the SOBP, the maximum likelihood estimation (MLE) method was applied to the detected distributions. The evaluated values with the MLE method were compared with those estimated from the measured dose distributions. As a result, the ranges were determined with the difference between the MLE range and the experimental range less than 1.0 mm for all targets. For the SOBP beams, the positions of distal edges were determined with the difference less than 1.0 mm. On the other hand, the difference amounted to 7.9 mm for proximal edges. 相似文献
94.
Renal p38 MAP kinase activity in experimental diabetes 总被引:3,自引:0,他引:3
Komers R Lindsley JN Oyama TT Cohen DM Anderson S 《Laboratory investigation; a journal of technical methods and pathology》2007,87(6):548-558
Renal cell activity of p38 mitogen-activated protein kinase (p38) is increased in the diabetic milieu. p38 mediates signals relevant for the development of diabetic nephropathy (DN). However, renal p38 in Type 1 diabetes in vivo, particularly in conditions reflecting the differences in metabolic control, and its activity in advanced stages of DN, has received less attention. We examined the p38 pathway in renal cortex of rats with streptozotocin diabetes (4 weeks) with poor (DS), moderate (DM), and intensive (DII) metabolic control, achieved by varying doses of insulin therapy. Renal p38 was also studied in 12-month diabetic rats with established nephropathy (DM12) and compared with age-matched controls. p38 activity (in vitro kinase assay and expression of phosphorylated (active) p38 (P-p38)) was increased in DM and DS rats, as compared with non-diabetic controls, and attenuated by intensive insulin treatment. In all groups, P-p38 was predominantly localized in macula densa cells. Diabetic rats also demonstrated P-p38 immunoreactivity in the distal tubule and glomeruli. Enhanced p38 activity in DS and DM rats was not associated with increases in expression of active mitogen-activated protein kinase 3/6, an activator of p38, but paralleled with increased expression of scaffolding protein transforming growth factor-beta-activated protein kinase 1-binding protein 1. Expression of mitogen-activated protein phosphatase-1 (MKP-1), one of the phosphatases involved in inactivation of mitogen-activated protein kinase signaling, was increased in all diabetic groups, irrespective of metabolic control. Renal p38 activation was also detectable in D12 rats with established albuminuria and glomerulosclerosis. In summary, renal cortical p38 activity was increased in diabetic rats at early and advanced stages of nephropathy, as compared with non-diabetic animals, and attenuated by improved metabolic control. p38 activation in diabetes is likely to occur via multiple pathways and cannot be explained by downregulation of MKP-1. 相似文献
95.
Wakasa Haruka Tsugami Yusaku Koyama Taku Han Liang Nishimura Takanori Isobe Naoki Kobayashi Ken 《Journal of mammary gland biology and neoplasia》2022,27(2):155-170
Journal of Mammary Gland Biology and Neoplasia - In the mammary glands during pregnancy, the alveolar buds are first branched from the mammary ducts after which they form the alveolar luminal... 相似文献
96.
Kenichi Oyama Noriaki Fukuhara Manabu Taguchi Akira Takeshita Yasuhiro Takeuchi Shozo Yamada 《Neurosurgical review》2014,37(2):261-267
A less invasive transsphenoidal approach with a keyhole dural opening for intrasellar arachnoid cysts is described. This approach was used to address seven sellar cystic lesions with suprasellar extension; they were six intrasellar arachnoid cysts (IACs) and one Rathke’s cleft cyst (RCC). In all cases, preoperative MRI revealed cerebrospinal fluid (CSF) intensity on both T1- and T2-weighted images. On preoperative contrast-enhanced MRI, five of the six IACs manifested posterior displacement of the flattened pituitary gland toward the dorsum sellae; one of the six IACs and the RCC exhibited a flattened pituitary gland on the anterior surface of the cyst. Wide cyst cisternostomy through a keyhole dural opening was carried out safely using a microscope with the support of a thin angled endoscope (30° and/or 70°, diameter 2.7 mm). As we aimed to avoid iatrogenic injury of the pituitary function, we found it difficult to obtain a sufficiently wide and precise opening of the cyst wall when the pituitary gland was located on the anterior surface of the cyst wall. Our approach facilitates safe cyst cisternostomy as wide as that obtainable by transcranial manipulation. In addition, CSF leakage is prevented by dural plasty using the fascia lata and stitching with 6-0 monofilament sutures. This technique can be adapted to address various sellar cystic lesions. However, as the posterior or anterior displacement of the normal pituitary gland in the presence of IACs or RCCs, respectively, affects the width of the cyst opening, our technique is more suitable for IACs than RCCs. 相似文献
97.
Inoue Takahiro Ishihara Ryu Shibata Tomotaka Suzuki Kosuke Kitagawa Yuko Miyazaki Tatsuya Yamaji Taiki Nemoto Kenji Oyama Tsuneo Muto Manabu Takeuchi Hiroya Toh Yasushi Matsubara Hisahiro Mano Masayuki Kono Koji Kato Ken Yoshida Masahiro Kawakubo Hirofumi Booka Eisuke Yamatsuji Tomoki Kato Hiroyuki Ito Yoshinori Ishikawa Hitoshi Tsushima Takahiro Kawachi Hiroshi Oyama Takashi Kojima Takashi Kuribayashi Shiko Makino Tomoki Matsuda Satoru Doki Yuichiro 《Esophagus》2022,19(3):375-383
Esophagus - Endoscopic diagnosis of the invasion depth of superficial esophageal squamous cell carcinoma (ESCC) is an important determinant of the treatment strategy. The three endoscopic imaging... 相似文献
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This technical report describes a simple procedure for verifying occlusal contact with the use of a new device that combines the functions of a tongue depressor and an articulating paper holder. Verifying occlusal contact and/or the maxillomandibular relationship record can be expected to be simpler and easier with this device compared to the conventional holder, especially for patients with tongue hypertrophy or obesity and those treated under general anesthesia, among others. 相似文献