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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
31.
Yoichiro Hosokawa D.D.S. D.D.Sc. Kazuyuki Minowa D.D.S. Satoru Abe M.D. Keiichi Ohmori D.D.S. D.D.Sc. Michio Yamasaki M.D. D.M.Sc. Masanobu Shindoh D.D.S. D.D.Sc. Tadashi Iizuka D.D.S. D.D.Sc. Mohiuddin Ahmed B.D.S. Akira Amemiya D.D.S. D.D.Sc. 《Oral Radiology》1991,7(1):1-6
A case of an odontogenic tumor which invaded the intracranial space from the mandible is reported. Judging from the radiographic
images it was similar to a malignant tumor. The patient died 17 years after the first visit. According to the final pathological
diagnosis, it was malignant odontogenic mixed tumor of low grade which did not belong to any of the WHO classification. 相似文献
32.
The case of a 75-year-old man with three synchronous carcinomas of the lung (large cell carcinoma, adenocarcinoma, and small cell carcinoma) is reported. This is the eighth well-documented case report in the literature; however, our case is the first to be reported with the newly described histological combination. 相似文献
33.
We examined the involvement of GABAergic neuronal systems in benzodiazepine-induced passive avoidance deficit. Chlordiazepoxide impaired the passive avoidance response dose dependently when it was given prior to training. Post-training administration of muscimol improved the performance of chlordiazepoxide-pretreated mice. The effects of muscimol were antagonized completely by the GABAA antagonist, bicuculline, and the muscarinic acetylcholine receptor antagonist, scopolamine, but not by the benzodiazepine receptor antagonist, flumazenil, when the latter was administered immediately after training. It appears from these results that the GABAergic neuronal system plays an important role in the benzodiazepine-induced passive avoidance deficit by interacting with the cholinergic neuronal system. 相似文献
34.
Hirofumi Nakanishi Akira Myoui Takahiro Ochi Katsuyuki Aozasa 《Journal of cancer research and clinical oncology》1997,123(6):352-356
Multidrug resistance (MDR) is an important problem in chemotheraphy for neoplastic disease. In humans, MDR is mainly mediated by P-glycoprotein (P-gp), a product of theMDR1 gene, which acts as a transmembrane protein pump and eliminates chemotherapeutic agents from the cells. Expression of P-gp was immunohistochemically studied by using two monoclonal antibodies, JSB-1 and C-219, on paraffin-embedded sections from 55 patients with soft-tissue sarcoma. The histological diagnosis of tumors was malignant fibrous histiocytoma in 24 cases, liposarcoma in 9, synovial sarcoma in 7, malignant neurogenic tumors in 6, leiomyosarcoma in 5, others in 4. The histological grade was determined on the basis of criteria previously proposed by us. Out of 55 cases, 34 (62%) were positive for P-gp expression. There was a significant difference in P-gp expression between high-grade (90%) and intermediate and low-grade tumors (46%) (P<0.005). Tumors expressing P-gp had a less favorable prognosis than P-gp-negative tumors in the high- and intermediate-grade tumors. The current study demonstrated that the estimation of P-gp expression could be used to select appropriate therapeutic modalities.Abbreviations
MDR
multidrug resistance
-
P-gp
P-glyco-protein 相似文献
35.
Takashi Ito Kazuo Shimamura Kiyoshi Shoji Akira Akatsuka Yasuyoshi Kiryu Norikazu Tamaoki Yoshiyuki Osamura 《Virchows Archiv : an international journal of pathology》1993,422(6):487-490
A rare case of urinary bladder carcinoma with granulocyte colony stimulating factor (G-CSF) production was reported. In an 83-year-old female, marked neutrophilia in the peripheral blood decreased from 132,500/mm3 to 3,300/mm3 after tumour resection. The tumour was a transitional cell carcinoma. The serum G-CSF level reduced from 238 pg/ml pre-operatively to normal (60 pg/ml) after the operation. Immunohistochemical investigation of the resected tumour with monoclonal antibody specific for G-CSF revealed positive staining in the carcinoma cells, confirming G-CSF secretion. 相似文献
36.
Abstract: We analyzed the expression of CEA, CA19-9, CA125, CA15-3 (DF3), PCNA and p53 immunohistochemically in 14 tissue specimens of mucosal cancers in adenoma, seven tubulovillous adenoma specimens, and 16 tubular adenoma specimens. The rates of positive staining for mucosal cancer in adenoma, tubulovillous adenoma and tubular adenoma specimens, respectively, were: for CEA: 100%, 85.7% and 75%; for CA19-9: 71.4%, 71.4% and 56.2%; for CA125:0%, 0% and 0%;for CA15-3 (DF3): 64.3 %, 0% and 0 %; for PCNA: 100%, 88.9% and 56.2%; and for p53: 35.7%, 0% and 0% . The results suggest that the expressions of CEA, CA19-9, CA15-3 (DF3), PCNA and p53 are related to colorectal tumorigenesis. None of the specimens studied showed staining for CA125, suggesting that CA125 is not involved in the early stages of colorectal carcinogenesis. There was no significant difference in the rates of positive staining for CEA and CA19-9 among mucosal cancer in adenoma, tubular adenoma and tubulovillous adenoma specimens. However, the rates of positive staining for PCNA and p53 were significantly higher in mucosal cancer in adenoma specimens than for tubular adenoma specimens (p<0.05), and the rate of CA15-3 (DF3) positive staining was significantly higher for mucosal cancer in adenoma than for tubulovillous adenoma (p<0.01) and tubular adenoma (p< 0.001) specimens. Therefore, the CA15-3 (DF3) antigen is an immunohistochemical marker for colorectal carcinomas. The present results suggest that CA15-3 (DF3), PCNA and p53 play important roles in the genesis of colorectal adenomas. 相似文献
37.
Yukinobu Nakaseko Kentaro Nabeshima Kazuhisa Kinoshita & Mitsuhiro Yanagida 《Genes to cells : devoted to molecular & cellular mechanisms》1996,1(7):633-644
Background : Fission yeast microtubule associating protein (MAP) p93Dis1 functions for sister chromatid separation: dis1 mutants fail to separate chromosomes, while the spindle elongates but without cyclin destruction. p93Dis1 localizes along microtubules in interphase cytoplasm, but shifts to the spindle pole body (SPB) and spindle microtubules upon the entry into mitosis. In this study, regions of p93Dis1 were dissected to examine their role.
Results : Nitrocellulose filter blotting shows that recombinant Dis1 binds to bovine brain microtubules in vitro . A basic central region rich in S, T and P is essential for this association. However, the whole p93Dis1 with N- and C-termini containing a conserved repeat motif and heptad repeats, respectively, is necessary for normal microtubule association in vivo . The N-truncated region also binds to microtubules but only to the portions near the SPBs. Overproduction phenotypes indicate that p93Dis1 greatly affects spindle formation and cell morphogenesis. The central region is essential but, by itself, not sufficient for generating such effects.
Conclusions : We propose that p93Dis1 consists of three regions which carry distinct properties for localization: the N-region for cell cycle dependent localization, the central region for direct microtubule association, and the C-region for SPB and nuclear localization. The essential role of p93Dis1 is carried out in the C-region, while the N-region acts as a regulator. 相似文献
Results : Nitrocellulose filter blotting shows that recombinant Dis1 binds to bovine brain microtubules in vitro . A basic central region rich in S, T and P is essential for this association. However, the whole p93
Conclusions : We propose that p93
38.
The effects of N-(2,6-dimethyl-phenyl)-2-(2-oxo-1-pyrrolidinyl) acetamide (DM-9384), a new pyrrolidone derivative, were investigated on ethanol- and chlordiazepoxide (CDP)-induced amnesia animal model using the passive avoidance task in comparison with aniracetam, another pyrrolidone derivative. Pretraining administration of DM-9384 attenuated ethanol- and CDP-induced amnesia, whereas aniracetam failed to do so. The effects of DM-9384 on CDP-induced amnesia were antagonized by bicuculline, a GABAA receptor antagonist, but not by scopolamine, a muscarinic acetylcholine receptor antagonist and flumazenil, a benzodiazepine receptor antagonist. These results suggest that DM-9384 attenuates CDP-induced amnesia by interacting with the GABAergic neuronal system. 相似文献
39.
Hiroyuki Yamamoto Fumio Itoh Akinori Senota Yasushi Adachi Mitsuru Yoshimoto Takao Endoh Yuji Hinoda Akira Yachi Kohzoh Imai 《Journal of clinical laboratory analysis》1995,9(5):297-301
The matrix metalloproteinase matrilysin (MMP-7) is a member of the matrix metallo-proteinase gene family, which is believed to play an important role in tumor invasion and metastasis. We have previously found that matrilysin mRNA is specifically expressed in colorectal cancers and adenomas and that its message is localized in the tumor cells themselves. We examined the effects of activated Ki-ras oncogene on the expression of matrilysin in colon cancer cells. We showed that both mRNA and the enzymatic activity of matrilysin were induced by the introduction of activated Ki-ras into SW1417 colon cancer cells. To understand the mechanisms regulating this induction, we analyzed alterations of AP-1 activity induced by activated Ki-ras, using the chloramphenicol acetyltransferase assay. AP-1 activity in SW1417 cells expressing activated Ki-ras was higher than that in control cells. The gel-shift assay also showed higher levels of AP-1 binding protein in SW1417 cells expressing activated Ki-ras than those in control cells. Our results suggest that activated Ki-ras may play a role in inducing expression of matrilysin through an AP-1-dependent pathway in colon cancer cells. 相似文献
40.
Two-level posterior lumbar interbody fusion for degenerative disc disease: improved clinical outcome with restoration of lumbar lordosis 总被引:2,自引:0,他引:2
Akira Hioki MD Kei Miyamoto MD PhD Hirotaka Kodama MD PhD Hideo Hosoe MD PhD Hirofumi Nishimoto MD Hirofumi Sakaeda MD PhD Katsuji Shimizu MD DMSc 《The spine journal》2005,5(6):600-607
BACKGROUND CONTEXT: Although posterior lumbar interbody fusion (PLIF) for degenerative lumbar diseases is routine, there are few reports on double-level PLIF. PURPOSE: To evaluate the clinical outcomes of double-level PLIF. STUDY DESIGN/SETTING: A retrospective study of operated cases in Gifu, Japan. PATIENT SAMPLE: Nineteen patients (8 men and 11 women, 59.5+/-10.2 years) who underwent double-level PLIF between 1996 and 2001. OUTCOME MEASURES: Operation time, blood loss, complications, the Japanese Orthopaedic Association (JOA) score for back pain and lumbar sagittal alignment were evaluated. METHODS: Patients were examined retrospectively at follow-ups of 3.6+/-1.7 years. Primary diseases were spondylolisthesis, spinal canal stenosis, degenerative scoliosis and herniated intervertebral disc. Fusion areas were L3 to L5 in 15 cases and L4 to S1 in 4 cases. RESULTS: The mean JOA score increased from an initial score of 12.9+/-3.5 to 21.3+/-4.9 at the final follow-up. There was a positive correlation (R=0.718, p<.001) between the increase in lordotic angle and the increase in the JOA score. Several parameters suggested that the surgical invasiveness was not minimal. CONCLUSION: Double-level PLIF provided satisfactory results and preserved lumbar spine lordosis. 相似文献