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11.
In order to study clinicopathologic features of hepatocellular carcinoma (HCC) and their relation to metastatic growth, all autopsied cases with confirmed HCC (n = 490) from a period with a high autopsy frequency in a well-defined population were analyzed. Cirrhosis, usually of micronodular type, was found in 72%. The gross appearance of the tumour was predominantly massive (46%) or multinodular (42%). The tumour involved both liver lobes in 72% or the right lobe alone in 20%. Histologically, trabecular growth (79%) and grade II of differentiation (52%) prevailed. Vascular invasion was noted in 56%, whereas involvement of the biliary tract was unusual (4%). Metastases especially involved lymph nodes (42%), lungs (18%) and skeleton (17%). Increased weight of the liver, multinodular appearance, involvement of both liver lobes, low grade of differentiation and vascular invasion were significantly associated with presence of metastases.  相似文献   
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Background: The cardiac safety of droperidol given at antiemetic doses is a matter of debate. Although droperidol potently inhibits human ether-a-go-go-related gene (HERG) channels, the molecular mode of this interaction is unknown. The role of amino acid residues typically mediating high-affinity block of HERG channels is unclear. It is furthermore unresolved whether droperidol at antiemetic concentrations induces action potential prolongation and arrhythmogenic early afterdepolarizations in cardiac myocytes.

Methods: Molecular mechanisms of HERG current inhibition by droperidol were established using two-electrode voltage clamp recordings of Xenopus laevis oocytes expressing wild-type and mutant channels. The mutants T623A, S624A, V625A, Y652A, and F656A were generated by site-directed mutagenesis. The effect of droperidol on action potentials was investigated in cardiac myocytes isolated from guinea pig hearts using the patch clamp technique.

Results: Droperidol inhibited currents through HERG wild-type channels with a concentration of half-maximal inhibition of 0.6-0.9 [mu]m. Droperidol shifted the channel activation and the steady state inactivation toward negative potentials while channel deactivation was not affected. Current inhibition increased with membrane potential and with increasing duration of current activation. Inhibition of HERG channels was similarly reduced by all mutations. Droperidol at concentrations between 5 and 100 nm prolonged whereas concentrations greater than 300 nm shortened action potentials. Early afterdepolarizations were not observed.  相似文献   

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Successful internal arterial embolization with steel coils in life-threatening bleeding after femoral fracture is described in an older patient.  相似文献   
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A set-up for D.C. recordings of slow ocular potentials such as the c-wave of the electroretinogram (ERG) as well as the fast oscillation (FO), the light peak (LP) and the dark trough (DT) in both clinical and experimental work is described. It includes matched calomel half-cells connected by saline-agar bridges to a corneal contact lens on the eye and a reference chamber on the forehead, a low-drift differential-input D.C. amplifier, an A/D converter, a computer, a thermoprinter, a flexible disc memory, a plotter, and a device for light stimulation controlled by the computer.Examples of the usefulness of the set-up in clinical work are shown in the form of D.C. c-wave ERGs of normal subjects as well as of patients with vitelliform macular degeneration, choriocapillaris atrophy, and retinitis pigmentosa. The direct corneal recording of the FO and LP is demonstrated as well. The different origins of the standing potential (SP) of the eye, the ERG c-wave, the FO and the LP are reviewed briefly.  相似文献   
16.
The two-phase reconstruction of the mandible with a 2.7-mm-Martin-reconstruction-plate creates a tumor free period that is followed by bone grafting to the embedded plate. We have treated 61 patients following this pattern from 2000 to 2005, follow-up was done in 56. 14 patients had received radiotherapy of 70?Gy. 43 plates healed in without any complications. Until 2005 bone grafting had been performed in 18 patients, in ten patients the plate had been removed.  相似文献   
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The aim of this study was to evaluate the shear bond strength of three resin cements to Vita Mark II ceramics under different pretreatments of the ceramic surface and to examine whether simplified pretreatment procedures would result in satisfying results compared to the state of the art. RelyX Unicem (RXU), Calibra (CAL), and Variolink II (VAR) were used as resin cements and bonded to machine milled feldspatic disks, pretreated in five different ways. (1) no pretreatment of the ceramic surface; (2) surface etched with hydrofluoric acid (HF); (3) ceramic surface silanized; (4) ceramic surface etched (HF) and silanized, (5) ceramic surface etched (HF), silanized, and covered with Heliobond. The shear bond strengths were measured initially, after 5000 and 10,000 thermocycles (TC). After 10,000 TC for CAL only procedure 5 resulted in a reliable adhesion median value of 10.7 MPa. VAR showed median values of 24.6, 17.2, and 18.1 MPa for pretreatments 5, 3, and 4, respectively. RXU performed 25.9, 22.0, and 11.0 MPa for procedures 5, 4, and 3, respectively. For procedure 2, RXU revealed the significantly highest value with 15.4 MPa (U-test, p = 0.05). Only RXU-luted specimens of procedure 1 survived the 10,000 thermocycles. The results revealed that a simplification of the ceramic pretreatment for VAR and RXU might be possible.  相似文献   
20.
A potential shortcoming of nonlive vaccines is their relative inefficiency in generating T cell responses, thus limiting their application in infections requiring cellular immunity. Here, we present a system to induce cellular immunity and to study the immunological implications of time-delayed dendritic cell (DC) apoptosis and antigen reprocessing in vivo. We generated a self-replicating cytopathic pestivirus RNA to enhance production and presentation of hepatitis C virus (HCV) antigens and to induce apoptosis in DC 24-48 hr after transfection. Replicon-transfected H-2(b) DCs used to immunize HLA-A2 transgenic mice induced protection upon challenge with a vaccinia virus expressing HCV antigens. Induction of cell death enhanced the immunogenicity of DC-associated antigen. Transfer of cellular material from vaccine DCs to endogenous antigen presenting cells was visualized in lymph nodes and spleen, and crossprimed CD8(+) T cells were characterized. The findings are relevant for the rational design of vaccines against noncytopathic pathogens like HCV.  相似文献   
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