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41.
Pyothorax-associated lymphoma (PAL) is a B-cell lymphoma which develops in the pleural cavity of patients with an over-20-year history of pyothorax. Aberrant expression of surface antigens is occassional in PAL, although genotype is not fully investigated. We report here a PAL with dual genotype, i.e., simultaneous immunoglobin (Ig) and T-cell receptor (TcR) gene rearrangement. An 82-year-old woman with pain on the left side of the chest was admitted. She had been suffering from pyothorax after artificial pneumothorax for treatment of tuberculosis of the pulmonary when she was 18 years old. The mass that was confined to the left pleural cavity affected by pyothorax was biopsied and histologically diagnosed as diffuse large cell lymphoma. The tumor cells were positive for CD20, CD16, and TIA-1 but negative for CD79a, CD45RO, CD43, CD3, and CD56. Surface antigen expression was further investigated in cultured cells, showing that the cultured cells did not express representative B-cell markers, except for CD20, as well as T-cell markers, but were positive for CD16, CD30, and CD103. Southern blotting revealed the monoclonally rearranged bands of both Ig heavy chain and TcR gene. The patients died of tumors 14 months after admission. Aberrant genotype and immunophenotype of PAL cells is discussed in reviewing the pertinent literature.  相似文献   
42.
Peripheral low-density area of hepatic tumors: CT-pathologic correlation   总被引:4,自引:0,他引:4  
To aid in the distinction between colorectal cancer metastasis to the liver and hepatocellular carcinoma, findings on computed tomographic (CT) scans taken more than 5 minutes after contrast material administration ("late-enhanced CT scans") and pathologic findings were compared. Late-enhanced CT scans of metastatic adenocarcinoma showed a peripheral low-density area (PLDA) that corresponded to viable tumor and a central high-density area that represented fibrous connective tissue. This phenomenon was recognized in 15 of 20 (75%) patients with metastatic adenocarcinoma and in one of 50 (2%) patients with hepatocellular carcinoma. Late-enhanced CT scans may be useful in distinguishing between metastatic nonmucinous colorectal cancer and hepatocellular carcinoma.  相似文献   
43.
BackgroundTo better understand the nature of magnetic resonance imaging (MRI) findings in schwannomas, especially in the “target sign” of these findings, the histopathological investigation was performed.MethodsThe MRI findings were correlated with histopathological features in 22 samples of schwannomas, which were mostly resected from the extremities. The histopathological analyses included alcian blue staining and immunohistochemical staining for S-100 protein, proliferating cell nuclear antigen (PCNA) and epithelial membrane antigen (EMA).ResultsSeven of the 22 samples of schwannomas of the extremities exhibited target signs including a peripheral zone of homogeneously high signal intensity and a central zone of heterogeneous signal intensity in T2-weighted images. Gadolinium-enhanced T1–weighted images demonstrated a central heterogeneous enhancement and a peripheral ring of homogeneously low signal intensity. Histopathologically, S-100 and PCNA were positive only in the central heterogeneous signal area. In contrast, EMA was only stained on the degenerative epi/perineurium in the peripheral zone.ConclusionIn schwannomas of the extremities showing target sign in T2-weighted images, histopathologically, the peripheral areas were suggested to be mucinous degeneration of the epineurium or perineurium, while the central areas were composed of truly neoplastic cells.  相似文献   
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Pharyngeal cancer patients treated with intensity-modulated proton therapy (IMPT) using a model-based approach were retrospectively reviewed, and acute toxicities were analyzed. From June 2016 to March 2019, 15 pharyngeal (7 naso-, 5 oro- and 3 hypo-pharyngeal) cancer patients received IMPT with robust optimization. Simulation plans for IMPT and intensity-modulated X-ray therapy (IMXT) were generated before treatment. We also reviewed 127 pharyngeal cancer patients with IMXT in the same treatment period. In the simulation planning comparison, all of the normal-tissue complication probability values for dysphagia, dysgeusia, tube-feeding dependence and xerostomia were lower for IMPT than for IMXT in the 15 patients. After completing IMPT, 13 patients completed the evaluation, and 12 of these patients had a complete response. The proportions of patients who experienced grade 2 or worse acute toxicities in the IMPT and IMXT cohorts were 21.4 and 56.5% for dysphagia (P < 0.05), 46.7 and 76.3% for dysgeusia (P < 0.05), 73.3 and 62.8% for xerostomia (P = 0.43), 73.3 and 90.6% for mucositis (P = 0.08) and 66.7 and 76.4% for dermatitis (P = 0.42), respectively. Multivariate analysis revealed that IMPT was independently associated with a lower rate of grade 2 or worse dysphagia and dysgeusia. After propensity score matching, 12 pairs of IMPT and IMXT patients were selected. Dysphagia was also statistically lower in IMPT than in IMXT (P < 0.05). IMPT using a model-based approach may have clinical benefits for acute dysphagia.  相似文献   
46.
Summary The 1-adrenoceptor subtypes of dog prostate were characterized in binding and functional experiments. In saturation experiments, [3H]prazosin bound to 1-adrenoceptors with high affinity. In the displacement experiments, unlabelled prazosin and WB4101 biphasically inhibited the binding of 400 pM [3H]prazosin, suggesting the presence of at least two distinct affinity sites for prazosin or WB4101. The proportion of high-affinity sites was approximately 10%. HV723 also recognized two distinct affinity sites but the proportion of high-affinity sites was approximately 20%. From these results the presence of three distinct 1-adrenoceptor subtypes was suggested: presumably subtypes 1A (high affinity for prazosin and WB4101), 1N (high affinity for only HV723) and 1L (low affinity for the three antagonists) according to the recently proposed 1-adrenoceptor subclassification. The density of subtype 1L was much higher than that of subtypes 1A and 1N subtypes. In the functional experiments, prazosin, WB4101 and HV723 competitively antagonized the contractile response to noradrenaline with low affinities close to those estimated for the 1L subtypes. These results suggest that the contractile response to noradrenaline in the dog prostate is mediated predominantly through 1L subtype -adrenoceptors.  相似文献   
47.
Rapid and reliable assessment of hepatic graft viability is important for successful orthotopic liver transplantation (OLTx). OLTx was performed in 11 pairs of pigs via a venovenous bypass. Six of these grafts were transplanted immediately (group A), while the other five were preserved in University of Wisconsin (UW) solution for 24 h and then transplanted (group B). All grafts were flushed with 300 ml of chilled (4°C) Ringer's lactate solution before reperfusion of the graft, when 20 ml of effluent from the graft was collected and the concentrations of ammonia, lactic acid, GOT, and LDH were measured. Four of the six pigs in group A survived longer than 3 days, while the other two pigs died of causes other than graft dysfunction. All five pigs in group B died either of hemoperitoneum or hemodynamic instability due to liver failure. The histology of postperfusion biopsies in group A showed minimal pathological changes, while the grafts in group B revealed moderate to severe ischemic injuries. Ammonia and lactic acid in the effluent of group B were significantly higher than those of group A (1511±216 vs 417±333 g/dl and 114.1±12.2 vs 91.4±12.2 mg/dl, respectively; P<0.05 in both cases). Before reperfusion, the rate of total adenine nucleotides in all of the substances in the graft, which were measured using high performance liquid chromatography (HPLC), inversely correlated with the ammonia levels in the effluent. We conclude that an analysis of the effluent, (i.e. the levels of ammonia and lactic acid), flushed from a hepatic graft before reperfusion could serve as a predictor of hepatic graft viability.  相似文献   
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Nucleos(t)ide analogs (NAs) cannot completely suppress the risk of hepatocellular carcinoma (HCC) in patients with chronic hepatitis B (CHB). This study aimed to identify the risk factors for HCC development in naïve CHB patients treated with current NA. Patients receiving NA (n = 905) were recruited retrospectively from the 17 hospitals of the Japanese Red Cross Liver Study Group. All treatment-naïve patients had been receiving current NA continuously for more than 1 year until the end of the follow-up. We analyzed the accuracy of predictive risk score using the area under receiver operating characteristic curve. The albumin–bilirubin (ALBI) score was significantly improved by NA therapy (−0.171 ± 0.396; p < 0.001 at Week 48). A total of 72 (8.0%) patients developed HCC over a median follow-up of 6.2 (1.03–15.7) years. An independent predictive factor of HCC development was older age, cirrhosis, lower platelet counts at baseline and ALBI score, and alpha-fetoprotein (AFP) at 1 year after NA therapy according to multivariate analysis. The accuracy was assessed using the PAGE-B, mPAGE-B, aMAP, APA-B, and REAL-B scores that included these factors. Discrimination was generally acceptable for these models. aMAP and REAL-B demonstrated high discrimination with 0.866/0.862 and 0.833/0.859 for 3- and 5-year prediction from the status of 1 year after NA therapy, respectively. Baseline age and platelet count, as well as ALBI and AFP one year after NA, were useful for stratifying carcinogenesis risk. The aMAP and REAL-B scores were validated with high accuracy in Japanese CHB patients.  相似文献   
50.
In this study, the prognostic value of determining the nuclear DNA content of thymomas by flow cytometry was evaluated. Of a total 31 resected thymomas, 10 (32%) showed DNA aneuploidy, the presence of which was significantly correlated with an advanced clinical stage of disease. The patients with an aneuploid tumor had a poorer prognosis than those with a diploid tumor, demonstrating a survival rate of 50% at 7 postoperative years, which was considerably less favorable than that of the patients with a diploid tumor, being 100% in the same period (p<0.05). Moreover, patients with a high DNA index (DI), i.e., a DI1.5, tended to have a poorer prognosis than those with a low DI. These findings indicated that the DNA content can be an important prognostic index in patients with thymomas.  相似文献   
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