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PURPOSE: The aim of this study is (1) to develop a new method of risk classification for clinically localized prostate cancer; (2) to examine it in terms of compatibility with existing data such as nomograms; and (3) to compare it with existing risk-grouping methods. MATERIAL AND METHODS: The new grading system introduced here consists of three factors. The first is a prostate-specific antigen (PSA) of 4.1-10.0 ng/ml (score 0), 10.1-20.0 ng/ml (score 1), and >20.0 ng/ml (score 2). The second is a Gleason score (GS) of 6 (score 0), 7 (score 1), and 8-10 (score 2). The third is T classifications (UICC 2002) of T1c-T2a (score 0), T2b-T2c (score 1), and T3a (score 2). The sum of the three scores was named Prostate Risk Index (PRIX). Then, the compatibility of PRIX with the Partin Table, Kattan Nomogram, and Roach's formula was examined. At the same time, PRIX was compared with D'Amico, the National Comprehensive Cancer Network (NCCN), and Seattle classifications. RESULTS: PRIX 0 corresponded to 1-2% of pathologic lymph node involvement (pLN+) according to the Partin Table; PRIX 1 to 3-4%; PRIX 2 to 7-10%; PRIX 3 to 14-18%; PRIX 4 to 24-29%; PRIX 5 to 32-37%; and PRIX 6 to 42%. PRIX well separated the risks with relatively narrow ranges of probability, while D'Amico, NCCN, and Seattle classifications generally gave wide ranges especially for high-risk groups, both in the Partin Table and Kattan Nomogram. Roach's formula sometimes overestimated the risk compared to the Partin Table. CONCLUSION: PRIX fully corresponded to the Partin Table in terms of pLN+, and corresponded to the other nomograms better than any existing risk-grouping method. PRIX may thus function as a prognostic factor or contribute to patient selection in clinically localized prostate cancer.  相似文献   
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Constructing and estimating a model to explain the mechanism of neurotic disorders is important and significant. The model helps the rearrangement or representation of knowledge obtained from professional physicians. However, it is a very difficult problem, because the objects requiring analysis are mental activities of human beings, and they originally include a comparatively large variance between individuals. The object data were obtained from patients with neurotic disorders who were diagnosed by several doctors for 10 years in a subagricultural areas in Japan. We analyzed the data and calculated the weights attached for personal information depending upon the similarity between the information and the kinds of neurotic disorders using the theory of fuzzy sets. From the results of our analysis, we constructed and estimated a model explaining the mechanism causing neurotic disorders as several linear equations. From data processing points of view, the estimation we attempted is placed in a kind of effective data compression with respect to discrete statistical data.  相似文献   
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A novel antitumor compound, N-β-dimethylaminoethyl 9-carboxy-5-hydroxy-10-methoxybenzo[a]-phenazine-6-carboxamide sodium salt (NC-190), was evaluated for antitumor activity in vitro against cultured tumor cell lines, and the kinetics of cell killing was elucidated. NC-190 strongly inhibited the growth of all of 3 murine tumor cell lines, 7 human tumor cell lines and 2 normal cell lines. With continuous exposure, the 50% inhibition concentrations were in the range of 0.005–0.06 μg/ml, except for KATO-III (2.15 μ g/ml). By colony-forming assay, concentrations of NC-190 giving 90% cell kill (IC90) at various exposure times were obtained with HeLa S3 cells. The plot of IC90exposure time on a log-log scale was linear for NC-190 with a slope of -1, which is typical for cell cycle phase-nonspecific agents. A 2 h treatment with NC-190 induced a rapid reduction in cell viability at doses of more than 3 μ g/ml. At the dose where colony formation was completely inhibited, cell viability was persistently reduced to below 20% during the cell culture period. NC-190 cauced a dose- and time-dependent reduction in DNA synthesis. The inhibitions of RNA and protein synthesis were less than that of DNA synthesis. Spectroscopic studies of NC-190 mixed with calf thymus DNA demonstrated that NC-190 was capable of interacting with DNA. However, DNA thermal denaturation studies suggested that intercalation of NC-190 was weak in comparison with those of classical intercalating drugs.  相似文献   
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均一吸收体中SPECT重建多解性的探讨   总被引:1,自引:0,他引:1  
通过对重建图像噪声特性的分析,间接证明SPECT的解具有多样性。分别用TretiakMetz、Gulberg、富谷武浩等推导的3种等价重建方法和Belini等推导的重建方法,经计算机模拟重建衰减均匀分布的图像,先预置相同的重建图像的空间分辨率,再比较它们的噪声特性。两种方法重建图像的噪声分布:前者近图像边缘时增大,而后者减小,从而间接证明在假定均匀衰减条件下,SPECT的重建有多解性。  相似文献   
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A 23-year-old woman had lower abdominal pain, diarrhea and bloody stool was admitted and given a diagnosis of influenza B. Her home doctor had started treatment by neuraminidase inhibitor (oseltamivir) the previous day. Colonoscopic examination revealed an area of hemorrhage and erosion in the left transverse colon. After halting oseltamivir treatment these symptoms disappeared and her colonoscopic findings improved. A drug-induced lymphocyte stimulation test was positive for oseltamivir. This case is the first reported case of acute hemorrhagic colitis induced by oseltamivir.  相似文献   
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PURPOSE: To evaluate the treatment results of low-dose-rate (LDR) and high-dose-rate (HDR) interstitial brachytherapy (ISBT) for T3 mobile tongue cancer. MATERIAL AND METHODS: Between 1974 and 1992, 61 patients with T3 mobile tongue cancer were treated with LDR ISBT using (192)Ir hairpins with or without single pins. In addition, between 1991 and 1999, 14 patients were treated with HDR ISBT. For nine patients treated with ISBT alone, the total dose was 59-94 Gy (median 72 Gy) within one week in LDR ISBT and 60 Gy/10 fractions/5 days in HDR ISBT. For 66 patients treated with a combination therapy of external beam radiotherapy (EBRT) and ISBT, the total dose was 12.5-60 Gy (median 30 Gy) of EBRT and 50-112 Gy (median 68 Gy) within 1 week in LDR ISBT or 32-60 Gy (median 48 Gy)/8-10 fractions/5-7 days in HDR ISBT. RESULTS: The 2- and 3-year local control rates of all patients were both 68%. The 2- and 3-year local control rates of patients treated with LDR ISBT were both 67%, and those with HDR ISBT were both 71%. The local control rate of patients treated with HDR ISBT was similar to those with LDR ISBT. CONCLUSIONS: ISBT for T3 mobile tongue cancer is effective and acceptable. The treatment result of HDR ISBT is almost similar to that of LDR ISBT for T3 mobile tongue cancer.  相似文献   
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Summary A novel antitumor compound, N--dimethylaminoethyl 9-carboxy-5-hydroxy-10-methoxybenzo[a]-phenazine-6-carboxamide sodium salt (NC-190) was evaluated for its antitumor activity in experimental murine tumor systems. In the initial studies with P388 leukemia (i.p.-i.p.), NC-190 led to an increase of >200% in life span (ILS), and 75% of the mice were alive on day 30, when the optimal dose (50 mg/kg, days 1–5) was given. Additionally, the compound had significant activities against i.p. inoculated mouse L1210 leukemia, B16 melanoma, M5076 reticulum cell sarcoma, sarcoma 180, mouse hepatoma MH134, and rat Yoshida sarcoma and Yoshida ascites hepatoma AH130. The optimal dose resulted in a >280% ILS with a 30-day survival of 50% in mice with L1210 leukemia (100 mg/kg, days 1–5), a 156% ILS in mice with B16 melanoma (50 mg/kg, days 1–5), a 98% ILS with a 90-day survival of 25% in mice with M5076 reticulum cell sarcoma (25 mg/kg, days 1, 5, 9, and 13), a >300% ILS with a 60-day survival of 50% in mice with sarcoma 180 (50 mg/kg, days 3–10), a 148% ILS with a 60-day survival of 25% in mice with MH134 (25 mg/kg, days 1–5), a 129% ILS with a 60-day survival of 12.5% in rats with Yoshida sarcoma (12.5 mg/kg, day 3–10), and a >161% ILS with a 60-day survival of 50% in rats with AH130 (6.3 mg/kg, days 3–10). In the experiments with s.c. inoculated tumors, NC-190 not only inhibited tumor growth, but also increased the life span of mice with Lewis lung carcinoma or B16 melanoma. The 60-day survivors accounted for 60% and 30% in mice with Lewis lung carcinoma and B16 melanoma, respectively. The compound significantly inhibited the spontaneous lung metastasis of Lewis lung carcinoma by more than 90% when eight daily i.v. injections were given. NC-190 was active by the i.p., s.c., and i.v. routes. Five consecutive daily i.p. doses (days 1–5) were more effective than a single dose (day 1), two doses (days 1 and 5), or three doses (days 1, 5, and 9). NC-190 warrants further study as a potential antineoplastic agent against human neoplasms, as it has a broad spectrum of antitumor activity and inhibits metastasis.Abbreviations ILS increase in life span - MST median survival time - MMC mitomycin C - ADM adriamycin - CPA cyclophosphamide - 5-FU 5-fluorouracil  相似文献   
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The neurotoxicity of epsilon-toxin, one of the major lethal toxins produced by Clostridium perfringens type B, was studied by histological examination of the rat brain. When the toxin was injected intravenously at a lethal dose (100 ng/kg), neuronal damage was observed in many areas of the brain. Injection of the toxin at a sublethal dose (50 ng/kg) caused neuronal damage predominantly in the hippocampus: pyramidal cells in the hippocampus showed marked shrinkage and karyopyknosis, or so-called dark cells. The dark cells lost the immunoreactivity to microtubule-associated protein-2, a postsynaptic somal and dendric marker, while acetylcholinesterase-positive fibers were not affected. Timm’s zinc staining revealed that zinc ions were depleted in the mossy layers of the CA3 subfield containing glutamate as a synaptic transmitter. The cerebral blood flow in the hippocampus was not altered significantly before or after administration of the toxin, as measured by laser-Doppler flowmetry, excluding the possibility that the observed histological change was due to a secondary effect of ischemia in the hippocampus. Prior injection of either a glutamate release inhibitor or a glutamate receptor antagonist protected the hippocampus from the neuronal damage caused by epsilon-toxin. These results suggest that epsilon-toxin acts on the glutamatergic system and evokes excessive release of glutamate, leading to neuronal damage.  相似文献   
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