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排序方式: 共有1205条查询结果,搜索用时 0 毫秒
1.
We report a newly developed MR simulation system for intracavitary brachytherapy for cervical cancer and subsequent treatment results. MR simulation was performed on six patients. The spatial relationship of the tumor to the bladder, rectum, bowel, applicators, etc. was depicted well. Doses to the tumor and surrounding normal tissues were read from isodose curves superimposed on the T2-weighted sagittal image. This system promises to be useful in customizing the dose distribution. 相似文献
2.
Naofumi Horikawa 《Seishin shinkeigaku zasshi》2007,109(7):709-711
3.
Hikaru Tanaka Naofumi Uesato Koki Shigenobu 《Naunyn-Schmiedeberg's archives of pharmacology》1995,351(4):391-397
Chronotropic and inotropic effects of histamine were examined in isolated atrial and ventricular preparations from embryonic and hatched chicken hearts. Histamine produced positive chronotropic and inotropic responses both in embryonic and hatched hearts. The responses to histamine in middle embryonic myocardia, which were observed in the micromolar range, were antagonized by H2 antagonists but not by H1, H3 antagonists and propranolol. Isobutylmethylxantine, an inhibitor of phosphodiesterase, produced a leftward shift of the concentration-response curve for the chronotropic effect of histamine in the embryo. The responses to histamine in myocardia from hatched chicks, which were observed in the milimolar range, appeared concurrently with the responses to tyramine during development and were antagonized by beta adrenoceptor antagonists but not by any of the histamine antagonists. The positive inotropic response to histamine in hatched ventricular preparations were greatly attenuated by reserpine pretreatment or in the presence of desipramine. Thus, we demonstrated that exogenously applied histamine produces positive chronotropic and inotropic responses in developing chicken hearts and that the mechanisms are different between embryonic and hatched chicks: direct action on H2 receptors in the embryonic heart and release of norepinephrine from sympathetic nerve terminals in hatched hearts. 相似文献
4.
Radiographic evaluation of periapical status and prevalence of endodontic treatment in an adult Japanese population. 总被引:3,自引:0,他引:3
Midori Tsuneishi Tatsuo Yamamoto Reiko Yamanaka Naofumi Tamaki Tomonori Sakamoto Kohzoh Tsuji Tatsuo Watanabe 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2005,100(5):631-635
OBJECTIVES: To determine the prevalence of periapical radiolucencies and endodontic treatment in an adult Japanese population. STUDY DESIGN: Periapical status and length of root fillings of 672 adult patients attending Okayama University Hospital of Dentistry were evaluated using full mouth intraoral radiographs. RESULTS: Overall, 87% of the subjects had root-filled teeth, and 70% exhibited an apical radiolucency. Of the 16,232 teeth examined, 21% had been root-filled, and, of these, 40% exhibited an apical radiolucency. Root-filled teeth that were overfilled or that were mandibular incisors had the highest prevalence of apical radiolucencies. CONCLUSIONS: The prevalence of root-filled teeth appears higher in this Japanese population than in Europe or America; however, the ratio of teeth with an apical radiolucency to root-filled teeth was within the range of that reported for other countries. Overfilled teeth and mandibular incisors are most likely to exhibit apical radiolucencies. 相似文献
5.
Expression of cytoplasmic TFF2 is a marker of tumor metastasis and negative prognostic factor in gastric cancer 总被引:8,自引:0,他引:8
Dhar DK Wang TC Maruyama R Udagawa J Kubota H Fuji T Tachibana M Ono T Otani H Nagasue N 《Laboratory investigation; a journal of technical methods and pathology》2003,83(9):1343-1352
Trefoil factor family 2 (TFF2) is a small peptide constitutively expressed in the gastric mucosa, where it plays a protective role in restitution of gastric mucosa. TFF2 has also been shown to be expressed in some gastric cancers, but its role in tumor metastasis and patient prognosis has not been examined. In this study, we examined TFF2 expression at both the mRNA and protein levels and correlated these results with the clinicopathologic characteristics and prognosis of gastric cancer patients. Among the 144 curatively resected samples, 43 (30%) were positive for TFF2. TFF2 expression was preferentially observed in the infiltrating tumor cells sparing the superficial cells. Significantly increased expression of TFF2 was noted in large tumors of the diffuse type. An increased prevalence of TFF2 expression was also found in tumors with advanced T and N stage and in patients with lymphatic and venous invasion. Accordingly, patients with TFF2-expressing tumors had a significantly worse disease-free survival, and in multivariate analysis, this finding remained significant as an independent prognostic factor. Taken together, our results suggest that TFF2 expression may play a role in gastric cancer invasion and as such could be a useful target for therapeutic intervention. 相似文献
6.
Studies have suggested that psoriasis vulgaris is mediated by type 1 T cells. In this study, we examined both chemokine receptor expression and intracellular cytokine production by circulating T cells to check the type 1/type 2 balance in psoriasis. CCR4+ and CXCR3+ T cells predominantly produced interleukin-4 and interferon-, respectively. The frequency of interferon--producing cells and that of CXCR3+ cells in circulating CD4+ T cells were similar for psoriatic patients and healthy control subjects. By contrast, the frequency of CCR4+CD8+ T cells and CCR4/CXCR3 ratio in circulating CD8+ T cells were significantly higher in psoriatic patients than in healthy control subjects. Analysis of intracellular cytokine production also indicated relative increase of type 2 CD8+ T (Tc2) cells in peripheral blood from psoriatic patients. The frequency of circulating Tc2 cells directly correlated with Psoriasis Area and Severity Index. Immunohistochemical analysis showed that not only CXCR3+CD8+ T cells but also a similar number of CCR4+CD8+ T cells infiltrated the psoriatic epidermis and dermis. Our findings suggest an increase in Tc2 cell number in blood from psoriatic patients, and the association of Tc2 cells with inflammation in psoriasis. 相似文献
7.
Tamaru N Hishikawa Y Ejima K Nagasue N Inoue S Muramatsu M Hayashi T Koji T 《Laboratory investigation; a journal of technical methods and pathology》2004,84(11):1460-1471
Although estrogen is known to play a crucial role in the pathogenesis of breast cancer, the molecular mechanisms underlying the action of estrogen remain elusive. In the present study, we focused on keratinocyte growth factor (KGF) and its receptor (KGFR) in the pathogenesis of breast cancer, as a growth factor mediating estrogen action, since significant roles of KGF were demonstrated in various steroid hormone-dependent tissues. First, using paraffin-embedded specimens from 42 breast cancer patients, we examined expression patterns of KGF and KGFR by both immunohistochemistry using newly generated antibodies and nonradioactive in situ hybridization with T-T dimerized synthetic oligonucleotide probes. We next compared the results with the expression of estrogen receptor (ER) alpha and beta, proliferative activity and apoptotic frequency (TUNEL staining). Also, the similar approaches were taken to analyze the expression and role of KGF in ER-positive (MCF7, ZR-75-1) and ER-negative (SK-BR-3, MDA-MB-231) human breast cancer cell lines in vitro. In the surgical specimens, KGF was expressed in cancer cells as well as stromal cells in 19/42 cases (45%), while KGFR was found in cancer cells in 24/42 cases (57%). The distribution of protein and mRNA in the analysis of both KGF and KGFR expression generally coincided. Moreover, KGF expression was closely associated with the expression of ER alpha, and the coexpression of KGF and KGFR significantly correlated with lower TUNEL index, but not with proliferative activity. In accordance with the in vivo findings, KGF expression was detected only in ER alpha-positive MCF7 and ZR-75-1 cells in vitro. And more importantly, we found the inhibitory effect of KGF upon the induction of apoptosis by anticancer drugs in MCF7 cells. Collectively, our results indicate that ER alpha may be involved in KGF expression, and that KGF may play antiapoptotic roles, rather than mitogenic, in human breast cancer. 相似文献
8.
Prevention of endotoxin shock by an antibody against leukocyte integrin {beta}2 through inhibiting production and action of TNF 总被引:2,自引:0,他引:2
Watanabe Shun-ichi; Mukaida Naofumi; Ikeda Naoki; Akiyama Mariko; Harada Akihisa; Nakanishi Isao; Nariuchi Hideo; Watanabe Yoh; Matsushima Kouji 《International immunology》1995,7(7):1037-1046
Septic shock remains a serious disorder associated with highmortality. Accumulating evidence indicates that TNF is a majorand essential mediator of endotoxin shock. We report here thatadministration of an antibody against CD18 dramatically reducedendotoxin-induced shock inrabbits as revealed by preventionof severe hypotension, metabolic acidosis and a pathologicalchange suggestive of disseminated intravascular coagulationwith concomitant inhibition of elevation of plasma TNF activity.The anti-CD18 antibody also inhibited the hypotension inducedby administering recombinant TNF. Furthermore, an antibody againsta ligand for CD18 complexes, intercellular adhesion molecule-1,also prevented TNF-induced shock as well as endotoxin shockinrabbits. These observations suggest that adhesion of leukocytesto endothelium may be of primary importance in the action ofTNF as well as in the production of TNF in vivo and that theantibody against adhesion molecules could be of therapeuticbenefit in life-threatening septic shock in humans. 相似文献
9.
Prognostic Significance of Proliferating Cell Nuclear Antigen (PCNA) in Squamous Cell Carcinoma of the Esophagus 总被引:1,自引:1,他引:0
Kinugasa Shoichi; Tachibana Mitsuo; Hishikawa Yoshitaka; Abe Shun'ichi; Yoshimura Hiroshi; Monden Naomi; Dhar Dipok Kumar; Nagasue Naofumi 《Japanese journal of clinical oncology》1996,26(6):405-410
Proliferating cell nuclear antigen (PCNA) has been shown tobe of prognostic significance in some gastrointestinal tumors.Immunohistochemical analysis was performed to determine whetherPCNA is useful for predicting the outcome of patients with squamouscell carcinoma of the esophagus. Using a mouse monoclonal antibody,PC 10, the expression of PCNA was studied in resected squamouscell carcinomas of the esophagus from 59 patients who had undergonecurative esophagectomy. None had received any preceding therapy.The proliferation rate was assessed in terms of the percentageof the PCNA-positive nuclear area relative to the total areaof cancer nuclei using a cell analysis system (CAS). Clinicopathologicalvariables including PCNA staining were assessed in relationto prognosis. Survival rate was obtained by the Kaplan-Meiermethod. The PCNA indices (percentage of the positive nucleararea) of the tumors varied from 4.4% to 96.2%. Among the clinicopathologicalvariables, only tumor size (5 cm) and depth of invasion werecorrelated significantly with PCNA index (P<0.05). Microscopically,PCNA was stained in non-keratinized cells but not in keratinizedcells. However the histological grade was not correlated withPCNA index. The survival rate was significantly worse in patientswith high PCNA indices (40%) than in those with low indices(<40%) (P<0.05). However, multivariate analysis revealedthat PCNA index was not an independent prognostic factor. 相似文献
10.
Hiroshi Yoshimura Dipok Kumar Dhar Hitoshi Kohno Hirofumi Kubota Toshiyuki Fujii Shuhei Ueda Shoichi Kinugasa Mitsuo Tachibana Naofumi Nagasue 《Clinical cancer research》2004,10(24):8554-8560
PURPOSE: Angiogenesis plays an important role in a multitude of biological processes including those of tumorigenesis and cancer progression. Hypoxia is the prime driving factor for tumor angiogenesis and the family of hypoxia-inducible factors (HIFs) plays a pivotal role in this process. The role of HIF in tumor angiogenesis has been underscored in different carcinomas but yet to be reported for colorectal carcinomas. EXPERIMENTAL DESIGN: In this study, we examined HIF [HIF-1alpha (HIF1) and HIF-2alpha (HIF2)] expression in 87 curatively resected colorectal carcinoma samples, and the results were correlated with clinicopathological factors, microvessel density, cyclooxygenase 2 expression, and patient prognosis. RESULTS: HIF1 (44.8%) was more frequently expressed than HIF2 (29.9%). Most of the clinicopathological factors representing the tumor aggressiveness were significantly correlated with overexpression of HIF2 but not with HIF1 expression. HIF2 expression had direct correlation with microvessel density and cyclooxygenase 2 expression. and, in contrast, HIF1 expression had a weak but significant inverse correlation in T1 and T2 tumors only. HIF2 expression alone and the combined expression of HIF1 and HIF2 had significant impact on patient survival. In the multivariate analysis, however, only the combined expression of HIF1 and HIF2 remained independently significant. CONCLUSIONS: Taken together, our results suggest that HIF2 expression may play an important role in angiogenesis and that the combined expression of HIF1 and HIF2 may play an important role in tumor progression and prognosis of colorectal carcinomas. Therefore, HIF expression could be a useful target for therapeutic intervention. 相似文献