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21.
BACKGROUND/AIMS: We previously developed a multi-step, incremental expansion method (multi-step method) for radio frequency ablation (RFA) in vitro, which prevented increases in pressure and reduced the ablation time as compared with other methods. In this study, we evaluated liver parenchymal pressure and portal endothelium damage during RFA with different devices and protocols in an in vivo porcine model. METHOD: Nine healthy female pigs were anaesthetized. RFA was performed with two different devices and protocols; one involved the use of a LeVeen needle with a single-step full expansion method or a multi-step method, and the other used a cool-tip needle with 40 or 60 W power. We measured the pressure in the liver parenchyma and the gallbladder during RFA. We also evaluated portal endothelium damage by NADH staining. RESULTS: The multi-step method with the LeVeen electrode resulted in the lowest parenchymal and intra-gallbladder pressures (multi-step method相似文献   
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OBJECTIVE: We studied the prognostic importance of high-resolution CT (HRCT) findings in lung adenocarcinomas. PATIENTS AND METHODS: HRCT findings (lesion size, percentage of ground-glass opacity (GGO) areas of lesion, and presence or absence of lobulation, coarse spiculation, air space, pleural tag, and multiplicity of lesion), clinical data (age and surgical method), and pathologic findings (tumor subtypes and presence or absence of nodal metastasis) in 64 consecutive patients with 64 peripheral adenocarcinomas of 20 mm or less (mean, 13 mm), including 36 women and 28 men with a mean age of 64 years were analyzed and correlated with survival of the patients using Kaplan-Meier method and stepwise Cox proportional hazards modeling. Follow-up periods of the patients ranged from 6 to 45 months (mean, 22 months). Tumors were classified into six subtypes (types A-F) according to tumor growth patterns defined by Noguchi et al. RESULTS: Six (9%) of the 64 patients died of lung cancer. In univariate analyses, a significant difference was noted for lesion size (P=0.043), the percentage of GGO areas (P=0.005), and tumor subtypes (P=0.006). Lesion size of <15 mm (n=35), a lesion with GGO areas of >57% (n=36), and type A (n=16) or type B adenocarcinomas (n=16) indicated a significantly better survival. In multivariate analyses using these three parameters as independent variables, the percentage of GGO areas was the only significant independent factor for survival (P=0.044, relative risk=0.95). CONCLUSION: GGO areas measured on HRCT may have an independent prognostic significance of small adenocarcinomas of the lung.  相似文献   
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The treatment of Barrett's esophagus is controversial. Current treatments include endoscopic therapy, surgical procedures, gastric acid-suppressive therapy with proton pump inhibitors (PPIs), and cancer chemoprevention such as nonsteroidal anti-inflammatory drugs. Endoscopic therapy combined with gastric acid suppressive therapy can result in squamous reepithelialization of the Barrett's mucosa. Antireflux surgery and PPIs therapy are potential options for the treatment of gastroesophageal reflux symptoms in patients with Barrett's esophagus. But there are no prospective studies that support any alternative approach to treatment. Although chemoprevention therapy may reduce cancer risk in Barrett's esophagus, no randomized controlled trials that prove its efficacy have been reported.  相似文献   
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BACKGROUND: The authors analyzed changes in the characteristics and survival rate of patients with hepatocellular carcinoma (HCC) in the past 25 years. METHODS: Trends in clinical characteristics and survival rate of patients with HCC were evaluated retrospectively based on data from 1365 patients who were diagnosed, treated, and followed between 1976 and 2000. RESULTS: Between 1976-1995, the number of patients with smaller tumors, a less advanced tumor stage, and with a lower Child-Pugh class increased markedly. No differences were observed in the distributions of these three factors between the periods 1991-1995 and 1996-2000. The year of HCC diagnosis, tumor size, tumor stage, Child-Pugh class, and the kind of initial treatment received correlated significantly with patient survival rates by multivariate analysis. The year of HCC diagnosis was found to contribute independently to the improvement in patient survival rates. Using the Kaplan-Meier comparison, the time periods during which the highest patient survival rates occurred were found to be 1991-1995/1996-2000, 1986-1990, and 1976-1985, in that order. The authors did not observe a difference with regard to survival rates between patients in the 1991-1995 and 1996-2000 groups. CONCLUSIONS: The characteristics of patients with HCC changed dramatically from 1976 to 1995 (but not in the past 10 years) toward the earlier detection of HCC. This contributed to the improvement noted in patient survival rates during this period. The year of HCC diagnosis was found to be an independent factor for the improved survival rates by multivariate analysis. This indicated that the progress of treatment and care for patients with HCC contributed to the annual improvement in patient survival rates.  相似文献   
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A replication defective herpes simplex virus-1 was evaluated as a therapeutic vector. Mantle cell lymphoma (MCL), hairy cell leukemia (HCL), and B-cell chronic lymphocytic leukemia (B-CLL) were chosen because leukemic cells were collectable from peripheral bloods in these diseases. Cells from six MCL, one HCL, and nine B-CLL were infected in vitro with T0Z.1 at 3 multiplicity of infection (MOI). Herpes simplex virus thymidine kinase (HSV-TK)/ganciclovir (GCV)-mediated suicide gene therapy showed 14.7% of mean tumor killing against leukemic B-cell malignancies. The mean tumor-killing effects were 8.7 and 17.1% in MCL and B-CLL, respectively. The effect against HCL was 29%. The study indicates that herpes simplex virus (HSV)-based gene therapy might be an effective strategy.  相似文献   
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We have previously shown significant potentiation of Ca2+ influx mediated by N‐methyl‐D ‐aspartate receptors, along with decreased microtubules‐associated protein‐2 (MAP2) expression, in hippocampal neurons cultured under static magnetism without cell death. In this study, we investigated the effects of static magnetism on the functionality of neural progenitor cells endowed to proliferate for self‐replication and differentiate into neuronal, astroglial, and oligodendroglial lineages. Neural progenitor cells were isolated from embryonic rat neocortex and hippocampus, followed by culture under static magnetism at 100 mT and subsequent determination of the number of cells immunoreactive for a marker protein of particular progeny lineages. Static magnetism not only significantly decreased proliferation of neural progenitor cells without affecting cell viability, but also promoted differentiation into cells immunoreactive for MAP2 with a concomitant decrease in that for an astroglial marker, irrespective of the presence of differentiation inducers. In neural progenitors cultured under static magnetism, a significant increase was seen in mRNA expression of several activator‐type proneural genes, such as Mash1, Math1, and Math3, together with decreased mRNA expression of the repressor type Hes5. These results suggest that sustained static magnetism could suppress proliferation for self‐renewal and facilitate differentiation into neurons through promoted expression of activator‐type proneural genes by progenitor cells in fetal rat brain. © 2009 Wiley‐Liss, Inc.  相似文献   
29.
Treatment‐related neuroendocrine prostate cancer is a lethal form of prostate cancer that emerges in the later stages of castration‐resistant prostate cancer treatment. Treatment‐related neuroendocrine prostate cancer transdifferentiates from adenocarcinoma as an adaptive response to androgen receptor pathway inhibition. The incidence of treatment‐related neuroendocrine prostate cancer has been rising due to the increasing use of potent androgen receptor pathway inhibitors. Typically, treatment‐related neuroendocrine prostate cancer is characterized by either low or absent androgen receptor expression, small cell carcinoma morphology and expression of neuroendocrine markers. Clinically, it manifests with predominantly visceral or lytic bone metastases, bulky tumor masses, low prostate‐specific antigen levels or a short response duration to androgen deprivation therapy. Furthermore, although the tumor initially responds to platinum‐based chemotherapy, the duration of the response is short. Based on the poor prognosis, it is imperative to identify novel molecular targets for treatment‐related neuroendocrine prostate cancer. Recent advances in genomic and molecular research, supported by novel in vivo models, have identified some of the key molecular characteristics of treatment‐related neuroendocrine prostate cancer. The gain of MYCN and AURKA oncogenes, along with the loss of tumor suppressor genes TP53 and RB1 are key genomic alterations associated with treatment‐related neuroendocrine prostate cancer. Androgen receptor repressed genes, such as BRN2 and PEG10, are also necessary for treatment‐related neuroendocrine prostate cancer. These genetic changes converge on pathways upregulating genes, such as SOX2 and EZH2, that facilitate lineage plasticity and neuroendocrine differentiation. As a result, on potent androgen receptor pathway inhibition, castration‐resistant prostate cancer transdifferentiates to treatment‐related neuroendocrine prostate cancer in a clonally divergent manner. Further understanding of the disease biology is required to develop novel drugs and biomarkers that would help treat this aggressive prostate cancer variant.  相似文献   
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