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排序方式: 共有6545条查询结果,搜索用时 15 毫秒
41.
Yumi Kojima Yoichi Aoki Hiroaki Kase Shoji Kodama Kenichi Tanaka 《International journal of clinical oncology / Japan Society of Clinical Oncology》1998,3(3):143-146
Background The purpose of this study was to assess the accuracy of contrast-enhanced magnetic resonance imaging (dynamic MR imaging)
in the evaluation of preinvasive and early invasive cancer of the cervix.
Methods Twenty-nine women with untreated squamous cell carcinoma of the cervix with either no stromal invasion or early stromal invasion
underwent pretreatment MR imaging and dynamic MR imaging within 4 weeks of surgical evaluation. The images were evaluated
for tumor detection and compared with results of histologic examination of the surgical specimens.
Results The lesions in 17 cases with histologically proven stromal invasion of 4 mm or greater were detected with dynamic MR imaging,
whereas lesions in only 8 of these cases were detected with T2 imaging. In 9 cases with stromal invasion between 4.0 mm and
5.0 mm, lesions were represented as early phase focal enhancement on dynamic MR images, but not detected on T2-weighted images.
In the 12 cases with less than 4 mm stromal invasion, no lesions were visualized on either T2-weighted images or dynamic MR
images, except in 1 case of glandular involvement without stromal invasion that appeared as enhancement on early-phase dynamic
MR imaging.
Conclusion Dynamic MR imaging detected more lesions of early stromal invasion in pretreatment imaging for cervical cancer than nonenhanced
MR imaging. 相似文献
42.
43.
Kenji Suzuki Sakiko Morita Hideo Muraoka Yoichi Niimi 《Nihon Arukōru Yakubutsu Igakkai zasshi》2005,40(3):219-232
OBJECTIVE: This study was carried out to examine fetal alcohol spectrum disorders (FASD) among Japanese children of alcoholic mothers. This is the first report concerning FASD in Japan. METHODS: The subjects were 30 alcoholic women who were inpatients in the Kurihama Alcoholism Center and had given birth to children. They were subjected to a semi-structured interview by the author. Sixty healthy women who had not drunk during pregnancy were used as a control group, and they also underwent semi-structured interviews. The alcoholic women were divided into two groups, 13 who drunk during pregnancies and 17 who did not drink. Twenty children experienced of prenatal alcohol exposure and 40 children did not. The three groups; i.e., 13 alcoholic mothers who had drunk during pregnancy and their 20 children (ALD group), 17 alcoholic mothers who had not drunk during pregnancy and their 40 children (ALND group) and 60 non-alcoholic control mothers and their 80 children (Control group), were compared concerning the mothers' drinking problems and abnormal deliveries, children's birth weights, congenital abnormalities, abnormalities of the central nervous system and psychological problems. RESULTS: The mean age of onset of problem drinking of the mothers in the ALD group was significantly lower than that in the mothers of the ALND group, and some of the mothers in the ALD group showed alcohol dependence before their pregnancies. The mean birth weights of the children of the ALD group, ALND group and Control group were 2816 g, 3128 g and 3142 g, respectively and the differences were significant. The children of the ALD group had significantly more abnormal birth episodes, developmental retardation and psychiatric symptoms than those in the other two groups. Among 20 children in the ALD group, FASD was suspected in 6 children (10% of the children of alcoholic mothers). Six children had low birth weights, abnormal birth episodes, mental retardation and psychiatric symptoms. CONCLUSION: One third of the Japanese children of alcoholic mothers had experiences of prenatal alcohol exposure and 10% of them had suspected FASD abnormalities. 相似文献
44.
Ezra R Lowe Andrew C Everett Anthony J Lee Miranda Lau Anwar Y Dunbar Vladimir Berka Ah-Lim Tsai Yoichi Osawa 《Drug metabolism and disposition》2005,33(1):131-138
Smoking causes a dysfunction in endothelial nitric-oxide synthase (eNOS), which is ameliorated, in part, by administration of tetrahydrobiopterin (BH(4)). The exact mechanism by which the nitric oxide deficit occurs is unknown. We have previously shown that aqueous extracts of chemicals in cigarettes (CE) cause the suicide inactivation of neuronal NO synthase (nNOS) by interacting at the substrate-binding site. In the current study, we have found that CE directly inactivates eNOS by a process that is not affected by the natural substrate l-arginine and is distinct from the mechanism of inactivation of nNOS. We discovered that CE causes a time-, concentration-, and NADPH-dependent inactivation of eNOS in an in vitro system containing the purified enzyme, indicating a metabolic component to the inactivation. The CE-treated eNOS but not nNOS was nearly fully reactivated upon incubation with excess BH(4), suggesting that BH(4) depletion is a potential mechanism of inactivation. Moreover, in the presence of CE, eNOS catalyzed the oxidation of BH(4) to dihydrobiopterin and biopterin by a process attenuated by high concentrations of superoxide dismutase but not catalase. We speculate that a redox active component in CE, perhaps a quinone compound, causes oxidative uncoupling of eNOS to form superoxide, which in turn oxidizes BH(4). The discovery of a direct inactivation of eNOS by a compound(s) present in tobacco provides a basis not only for further study of the mechanisms responsible for the biological effects of tobacco but also a search for a potentially novel inactivator of eNOS. 相似文献
45.
46.
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ISCT: The Professional Organization for those Working in Cell-basedResearch and Therapy (http://www.celltherapy.org/) Established in 1992, International Society for Cellular Therapy(ISCT), formerly International Society for Hematotherapy andGraft Engineering (ISHAGE), 相似文献
47.
Sakurada T Kikuchi Y Obata H Suzuki T Hirano T Kusajima K 《Kyobu geka. The Japanese journal of thoracic surgery》2000,53(13):1073-1075
We report twelve cases of minimally invasive coronary artery bypass grafting via small laparotomy using right gastroepiploic artery (RGEA) to the right coronary artery. Seven patients were operated on without partial sternotomy (N group), and lower partial sternotomy with Octopus 2 stabilization system was used in five of the cases (P group). Postoperative Doppler echographic imaging or angiographic study showed all RGEA grafts were functioning well in P group. However, graft occlusion was observed in two of the cases in N group. Inferior partial sternotomy combined with Octopus 2 stabilization system produce a clear surgical view, which avoids of both full-sternotomy and cardiopulmonary bypass. This method might be useful especially for reoperation. 相似文献
48.
Kikuchi Y Sakurada T Suzuki T Obata H Kusajima K 《Kyobu geka. The Japanese journal of thoracic surgery》2000,53(4):295-300
From April, 1999 to November, 1999, 8 patients underwent the aortic valve replacement using Medtronic Freestyle aortic root bioprosthesis. Mean age was 67.8 years old. Aortic valve etiology was as follows, AS: 1 case, AR: 2 cases, ASR: 3 cases, IE: 1 case, mechanical valve malfunction due to subvalvular pannus: 1 case. The implanted valve size was 25: 2 cases, 23: 3 cases, 21: 1 cases, 19: 2 cases. Surgical technique was subcoronary: 7 cases, full-root: 1 case. Post-op 2D-echo revealed tribial aortic valve incompetence in two cases because of size discrepancy between the aortic annulus and the ascending aorta. Pacemaker implantation was needed in 1 case because of the complete A-V block. In comparison with 5 cases of aortic valve replacement with Hancock II performed in same period, there were no significant differences about the implanted valve size and mean systolic pressure gradient, but the effective orifice area in Freestyle cases was significantly larger than Hancock II cases. 相似文献
49.
AdIκBα转染通过诱导凋亡逆转人非小细胞肺癌对泰素的耐药性 总被引:2,自引:1,他引:1
目的研究携带抑制性核因子κBα(IκBα)的腺病毒(AdIκBα)联合化疗对人非小细胞肺癌细胞株H460及H460荷瘤小鼠的作用。方法(1)检测50%抑制浓度(IC50)以确定化疗单用或联合AdIκBα对H460细胞增殖的影响,同时采用Annexin-V/PI染色法和caspase3活性测定来检测治疗引起的细胞凋亡情况;(2)观察泰素单用及联合不同浓度AdIκBα转染对H460荷瘤小鼠的作用,同时通过免疫组化染色观察核因子κB(NFκB)与p53及NFκB与血管内皮生长因子(VEGF)之间的关系。结果(1)联合AdIκBα3moi转染明显降低了泰素对H460的IC50,与激活caspase3途径而诱导了更多的细胞凋亡有关;在低剂量化疗组,联合治疗的疗效更加明显。(2)体内联合治疗明显抑制了H460荷瘤小鼠的肿瘤生长;免疫组化染色证实泰素治疗诱导了H460移植瘤细胞的NFκB表达增加,AdIκBα转染则消除了其表达,同时伴有轻度增加的VEGF表达,而p53表达不受影响。结论IκBα可通过阻滞NFκB表达和诱导凋亡而增加化疗疗效,同时减弱了VEGF表达,但与p53状态无关。推测联合治疗可减少化疗药的剂量,从而增加临床应用的耐受性。 相似文献
50.
Kanto S Sugawara J Masuda H Sasano H Arai Y Kyono K 《Fertility and sterility》2008,90(5):2010.e5-2010.e7