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61.
Hepatoid adenocarcinoma (HAC) is a special type of extrahepatic adenocarcinoma, which has a striking morphologic similarity to hepatocellular carcinoma. Seven HACs arising in the stomach and one in the lung, all with liver metastasis, were studied. They shared clinical features, such as old age, high serum alpha-fetoprotein level, aggressive behavior, and hepatic tumor in absence of risk factors for hepatocellular carcinoma (HCC). Morphologically, tumors were characterized by an admixture of tubulo-and/or papillary adenocarcinoma with hepatoid foci. In six cases, liver metastases showed an exclusive hepatoid differentiation, virtually indistinguishable from HCC with solid growth pattern. As HAC and HCC cannot be differentiated on the basis of morphology alone, differences in immunohistochemical reaction patterns would be of considerable diagnostic help. Immunostaining for CK7, CK8, CK18, CK19, CK20, alpha-fetoprotein, p-CEA, and HepPar1 revealed that hepatoid areas of both primary and metastatic HAC have a specific immunoprofile, distinctive of this entity. On the one hand, positivity of virtually all HACs for alpha-fetoprotein, CK8, CK18, and the membranous, canalicular staining for polyclonal carcinoembryonic antigen underline its hepatoid nature. On the other hand, positive staining for CK19 and CK20 and frequent negativity for HepPar1 in both primary tumors and their metastases were distinctive features of HAC. Furthermore, HAC differs from combined hepatocellular cholangiocarcinoma, being negative for CK7. In addition, for comparison of immunohistochemical results, we stained with the same antibody panel a tissue microarray of 121 HCCs. Comparative genomic hybridization study of three HAC supports their hepatoid differentiation as aberrations found in HAC are common in HCC (4q-, 8p-), and hepatoblastoma (Xq+), respectively.  相似文献   
62.
PURPOSE: The purpose of this study was to determine whether an ultra-endurance event is a strong stimulus to increase albumin synthesis involved in the process of intravascular albumin mass increase associated with transient hypervolemia. METHODS: The albumin synthetic rate was measured in six young men, 3 d before (C) and on the 1st (R1) and 8th (R8) days of the recovery from an ultra-endurance trial (5 h daily for 4 d). Albumin fractional (FSR) and absolute (ASR) synthetic rate were determined using a primed-constant infusion of [1(-13) C] leucine. Plasma volume (PV) using Evans Blue dye dilution and total body water (TBW) using bioelectrical impedance analysis were measured on C, R1, and R8. RESULTS: On R1 as compared with C: 1). PV (+23.3 +/- 3.2%; P相似文献   
63.
Large tumor burdens in advanced non-small-cell lung carcinoma (NSCLC) are thought to be immunosuppressive. To determine whether CD8-mediated immune responses could be elicited in stage IIIB/IV NSCLC patients, 14 subjects were immunized several times with allogeneic NSCLC cells transfected with CD80 (B7.1) and HLA-A1 or A2. Patients enrolled were matched or unmatched at the HLA A1 or A2 locus and their immune response compared. Immunization significantly increased the frequencies of interferon-gamma secreting CD8 T cells in all but one patient in response to ex vivo challenge with NSCLC cells. The CD8 response of matched and unmatched patients was not statistically different. NSCLC reactive CD8 cells did not react to K562. Clinically, five of 14 patients responded to immunization with stable disease or partial tumor regression. The study demonstrates that CD8 Ifn-gamma responses against nonimmunogenic or immunosuppressive tumors can be evoked by cellular vaccines even at advanced stages of disease. The positive clinical outcome suggests that nonimmunogenic tumors may be highly susceptible to immune effector cells generated by immunization.  相似文献   
64.
BACKGROUND: Cytochemical staining has been used in the diagnosis of acute leukemia for more than 20 years. The general availability of flow cytometers and an extensive panel of antibody reagents useful for characterizing blood cell lineage question the usefulness of continuing routine use of the cytochemical staining for the diagnosis of acute leukemia. PATIENTS AND METHODS: Test results were evaluated in 122 (n = 122; 112 with acute lymphocytic leukemia and 10 with acute myeloid leukemia) patients selected from among 320 patients with acute leukemia at Texas Children's Hospital in 1997 and 1998. Results were selected for review if the clinical encounter represented the initial diagnostic work-up and if data were available from cytochemical staining and flow cytometry studies. RESULTS: Cell lineage classification derived from flow cytometry and cytochemical stains were in agreement in all cases. Definitive diagnoses were feasible using flow cytometry results alone in 120 of 122 patients (98.4%) as compared with only 99 of 122 patients (81.2%) when only cytochemical staining results were considered. In two patients with inconclusive flow cytometry results, cytochemical staining alone provided information sufficient for diagnosis. CONCLUSIONS: Results from this study indicate that with few exceptions, flow cytometry studies alone provide sufficient information for diagnosis and management of acute leukemia in children. Nevertheless, cytochemical staining should be available for those cases in which flow cytometry results fail to allow a definitive diagnosis. A modified testing protocol is recommended.  相似文献   
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Bone marrow is the residence site of mesenchymal stem cells (MSC), which upon commitment and maturation develop into several mesenchymal phenotypes. Recently, we have described the presence of MSC in human cord blood (cbMSC) and informed that their properties are the same as those for MSC obtained from adult bone marrow. In this study we have investigated the capability of transplanted cbMSC to home and survive in the marrow of unconditioned nude mice. cbMSC utilized for transplantation studies were characterized by morphology, differentiation potential, and immunophenotype. After transplantation by systemic infusion, human DNA (as detected by PCR amplification of human-specific beta-globin gene) was detected in the marrow of recipients as well as in ex vivo-expanded stromal cells prepared from the marrow of transplanted animals. These results demonstrate homing and survival of cbMSC into the recipient marrow and also suggest a mesenchymal-orientated fate of engrafted cells, because human DNA was also detected in cells of other recipient tissues, like cardiac muscle, teeth, and spleen.  相似文献   
67.
This retrospective study of risk factors for testicular atrophy in HIV-infected men investigates the relationship between complications of AIDS such as wasting or opportunistic illness and testicular atrophy. Microscopic sections of the right testis were evaluated for testicular atrophy by assessing the mean score in each of 80 selected HIV-infected patients who underwent an autopsy during a one-year period. A significant association was observed between testicular atrophy and body mass index (BMI) (P=0.0496). Thus, underweight patients with HIV infection were 3.52 times more likely to have testicular atrophy than those with acceptable body weight. Other significant associations between other variables were not found.  相似文献   
68.
Background. Trainees in hematology oncology need to learn development and regulation of clinical research protocols. Methods. We hypothesized that rotation on the Institutional Review Board (IRB) and Protocol Review and Monitor Committee (PRMC) at our university could improve fellows’ understanding of clinical trial development and regulation. Results. Since 1999, 20 fellows in our training program have rotated through either IRB or PRMC for 3 months. We evaluated their experiences by anonymous questionnaire with 13 quantitative, 1 yes-or-no, and 4 open-ended questions and correlated responses to their demographic characteristics. Conclusions. We report here these fellow’s experiences in attending these meetings. We also describe other benefits of IRB/PRMC participation in training fellows, and finally propose to other fellowship programs to consider this educational approach as a way of enhancing hematology/oncology training  相似文献   
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