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排序方式: 共有2053条查询结果,搜索用时 15 毫秒
91.
Osamu Tanaka Shinya Hayashi Masayuki Matsuo Masahiro Nakano Yasuaki Kubota Sunaho Maeda Kazuhiro Ohtakara Takashi Deguchi Hiroaki Hoshi 《Radiotherapy and oncology》2008,88(1):115-120
PURPOSE: To compare the dosimetric results between MRI-based and TRUS-based preplanning in permanent prostate brachytherapy, and to estimate the accuracy of MRI-based preplanning by comparing with CT/MRI fusion-based postimplant dosimetry. METHODS AND MATERIALS: Twenty-one patients were entered in this prospective study with written informed consent. MRI-based and TRUS-based preplanning were performed. The seed and needle locations were identical according to MRI-based and TRUS-based preplanning. MRI-based and TRUS-based preplanning were compared using DVH-related parameters. Following brachytherapy, the accuracy of the MRI-based preplanning was evaluated by comparing it with CT/MRI fusion-based postimplant dosimetry. RESULTS: Mean MRI-based prostate volume was slightly underestimated (0.73 cc in mean volume) in comparison to TRUS-based volume. There were no significant differences in the mean DVH-related parameters except with rectal V(100)(cc) between TRUS-based and MRI-based preplanning. Mean rectal V(100)(cc) was 0.74 cc in TRUS-based and 0.29 cc in MRI-based preplanning, respectively, and the values demonstrated a statistical difference. There was no statistical difference in mean rectal V(150)(cc), and rectal V(100)(cc) between MRI-based preplanning and CT/MRI fusion-based postimplant dosimetry. CONCLUSION: Prostate volume estimation and DVH-related parameters in MRI-based preplanning were almost identical to TRUS-based preplanning. From the results of CT/MRI fusion-based postimplant dosimetry, MRI-based preplanning was therefore found to be a reliable and useful modality, as well as being helpful for TRUS-based preplanning. MRI-based preplanning can more accurately predict postimplant rectal dose than TRUS-based preplanning. 相似文献
92.
Yasuaki Hayashino Shunichi Fukuhara Yoshimi Suzukamo Tomonori Okamura Taichiro Tanaka Hirotsugu Ueshima the HIPOP-OHP Research group 《BMC public health》2007,7(1):129
Background
The effect of sleep on the risk of developing diabetes has not been explored in an Asian population. The objective of this study is to investigate the effect of self-reported sleep duration and sleep quality on the risk of developing diabetes in a prospective cohort in Japan. 相似文献93.
Yasuaki Tamura Satoru Takashima Joong-Moon Cho Weimin Qi Kenjiro Kamiguchi Toshihiko Torigoe Shuji Takahashi Itaru Hirai Noriyuki Sato Kokichi Kikuchi 《Cancer science》1996,87(6):623-630
Certain MHC class I molecules on target cells are known to inhibit the cytotoxic action of NK cells. By using monoclonal antibody (mAb) Cho-1, we have found inhibitory non-MHC class I cell surface molecules that are noncovalently-associated with 200 kDa and 40 kDa antigens. Poly I-C-induced rat NK cells were not cytotoxic to rat fetus-derived fibroblast WFB cell line. In contrast, NK cells were cytotoxic to H- ras oncogene-induced transformants of WFB, W14 and W31. FACS analysis indicated that mAb Cho-1 reacts with WFB, but not with W14 and W31 cells. Thus, this antigen may disappear concomitantly with cell growth and transformation. Cho-1 antigens were also expressed on other NK-resistant lines, such as mouse BALB3T3 fibroblast, EL-4 lymphoma and human fibroblast HEPM. However, they were not expressed on NK-sensitive mouse YAC-1 and H- ras transformant (Brash) of BALB3T3 cells. Furthermore, treatment of target cells with IFN-γ clearly induced the cell surface expression of Cho-1 antigens, and conferred a resistance to NK cytolysis on target cells. These data strongly suggest that Cho-I antigen expression may correlate with target cell susceptibility to NK cells. Indeed, treatment of NK-resistant WFB as well as HEPM cells with F(ab')2 fragments of mAb Cho-1 resulted in the acquisition of susceptibility to NK cytolysis. Cho-1 antigens may be novel molecules that regulate the NK resistance of cells. 相似文献
94.
Yagi H Midorikawa T Sakamoto M Masuda E Saitoh M Takeyama Y Haku E Ishibashi K Nemoto H Kikuchi H Sasaya S Yamaguchi M Sanada Y Kumada K 《Nihon Geka Gakkai zasshi》2002,103(5):441-447
We have already reported that the ratio of portal venous flow 30 min after oral intake of glucose 75 g to that before intake (PVFR30), measured using pulsed-Doppler ultrasonography (US), correlated significantly with other indicators of liver function and that it could be used to estimate hepatic function before surgery, including liver resection. In this study, to assess the disadvantages of pulsed-Doppler ultrasonography, PVFR30 was measured using two-dimensional (2D) phase-shift (PS) magnetic resonance imaging (MRI). PVFR30 was measured in 17 patients and 7 volunteers: 13 with liver cirrhosis (LC) and 11 without LC (non-LC). Portal venous flow could be measured in all patients without any disturbance of intestinal gas or patient fat, or the high degree of technical skill that Doppler US requires. PVFR30 was significantly lower in the LC group than in the non-LC group. In addition, it correlated significantly with other indicators of liver function, including the indocyanine green clearance test, prothrombin time, hepaplastin test, and cholinesterase activity. These results suggest that PVFR30 measured by 2D PS MRI can be used to estimate liver function, and that this MRI method can be performed more easily than pulsed-Doppler US. 相似文献
95.
96.
Esumi Y Suzuki Y Itoh Y Uramoto M Kimura K Goto M Yoshihama M Ichikawa T 《The Journal of antibiotics》2002,55(3):296-300
The structure of propeptin, a new inhibitor of prolyl endopeptidase isolated from Microbispora sp. SNA-115, was determined. FAB/MS, Edman degradation and amino acid analysis revealed propeptin to be a cyclic polypeptide consisting of 19 common L-amino acids. By FAB/MS and protein chemical methods, the primary sequence of propeptin was determined to be Gly1-Tyr-Pro-Trp-Trp-Asp-Tyr-Arg-Asp9-Leu-Phe-Gly-Gly-His-Thr-Phe-Ile-Ser-Pro19, which cyclizes between the beta-carboxyl group of Asp9 and the a-amino group of Gly1. 相似文献
97.
98.
Neuroprotective effect of NS-7, a novel Na+ and Ca2+ channel blocker,in a focal ischemic model in the rat 总被引:4,自引:0,他引:4
Katsumata T Muramatsu H Nakamura H Nishiyama Y Aoki Y Katayama Y 《Brain research》2003,969(1-2):168-174
NS-7 is a novel, voltage-dependent Na(+) and Ca(2+) channel blocker. This study evaluated the in vivo neuroprotective effect of NS-7 in a rat transient focal ischemic model when administered during occlusion. Left middle cerebral artery occlusion was induced in adult male Sprague-Dawley rats for 120 min using an intraluminal thread method. The rats received a single intravenous injection of NS-7 or saline (control group) just after the onset of ischemia, and at 30, 60 and 120 min after ischemia. Their brains were removed after 48 h reperfusion, sectioned, and stained with hematoxylin and eosin. Animals were evaluated by neurological examination at 120 min ischemia and 48 h reperfusion. Infarcted cortex and striatum were measured quantitatively and infarction volumes were calculated. Cortical infarction volumes were 128+/-74 (NS-7) and 214+/-64 mm(3) (control) immediately after the ischemia group, 155+/-48 (NS-7) and 225+/-12 mm(3) (control) after the 30 min group, 160+/-54 (NS-7) and 225+/-48 mm(3) (control) after the 60 min group, and 176+/-43 (NS-7) and 223+/-38 mm(3) (control) after the 120 min group. Cortices in NS-7-treated groups were significantly less infarcted than in control groups at all treatment times. There was no significant difference in the striatal infarction volume between the treatment and control groups. Neurological examination showed that hemiparesis and abnormal posture of the NS-7 groups were significantly more improved at 48 h reperfusion than those of the control groups without posture examination in the 120 min group. These observations suggest that NS-7 may be a new potential therapeutic agent for the acute phase of cerebral infarction. 相似文献
99.
Saijo Y Reiko K Sata F Katakura Y Urashima Y Hatakeyama A Mukaihara N Kobayashi S Jin K Iikura Y 《[Nihon kōshū eisei zasshi] Japanese journal of public health》2002,49(11):1169-1183
OBJECTIVE: The aim of this study was to clarify the "Sick House Syndrome" which has recently received increasing attention, and to investigate relationships between symptoms and the state of general dwellings in Hokkaido. METHODS: Questionnaires were sent to residents in 1775 dwellings, mainly solitary houses built or remodeled within the past few years by 24 construction companies in Sapporo and its environs, and answers was received from 564. The questionnaires included queries about building structure and characteristics, the residents' habits in the home, and subjective symptoms. We requested one resident who had the most severe symptoms in the dwelling to answer a questionnaire about symptoms. We classified the symptoms into 11 categories, and selected those that developed or were aggravated after the building or remodeling. We defined dwellings in which inhabitants complained of one or more categories of symptoms as the group with sick-house-related disease (developed or aggravated group: DA group), and those in which the inhabitants complained of two or more symptoms as the group with sick house syndrome (more than one organic symptom group: MO group)". Associations between symptoms and dwellings were then studied. RESULTS: There were 201 dwellings for which residents complained of symptoms (37.2%). Of these, 94 were in the DA group (16.7%), and 57 (10.1%) in the MO group. The symptoms that developed or were aggravated after building or remodeling of the dwellings were throat, 7.1%, dermal, 6.9%, psychoneural, 5.3%, eye, 5.1%, and nasal problems, 4.1%. Unpleasant odors form furniture were significant in both groups (DA: crude odds ratio (OR) 2.66, MO: OR 3.24). Use of aromatics was significant in group DA (OR 1.78). Condensation on windows and mold growth in the dwellings were significant in both groups (condensation on windows; DA: OR 2.98, MO: OR 3.32, mold growth; DA: OR 3.11, MO: OR 3.24). In addition, the percentage of dwellings for which residents complained of symptoms increased with signs of dampness (condensation on windows and mold growth). On logistic regression analysis, condensation on windows and mold growth were significant in both groups, and unpleasant odors from furniture in the MO group. CONCLUSION: It is suggested that symptoms of sick house syndrome are associated with high humidity such as condensation on windows and mold growth, odors from furniture and use of aromatics. 相似文献
100.
Watanabe T Fujisawa H Hasegawa M Arakawa Y Yamashita J Ueda F Suzuki M 《American journal of clinical oncology》2002,25(4):414-417
Metastasis of systemic cancer to intracranial tumors is a rare event. The authors report a case of 49-year-old woman with such occurrence, whose breast cancer metastasized to a preexisting parasagittal meningioma at a postoperative interval of 1.5 years. She was admitted to our hospital because of progressive right hemiparesis. Magnetic resonance imaging revealed newly emerged perifocal edema and inhomogeneous contrast enhancement of the meningioma. High choline/creatine ratio and lactate/lipid peak on proton magnetic resonance spectroscopy suggested malignancy. She underwent a tumor resection, and pathologic examination revealed intratumoral metastasis of breast cancer in a transitional meningioma. Immunoreactivity of E-cadherin was detected in both meningioma and breast cancer cells. It is suggested that abrupt appearance of symptoms, inhomogeneous enhancement, and perifocal edema of meningioma is a sign of intratumoral metastasis from systemic cancers. 相似文献