1,008 research outputs found
Histochemical and immunohistochemical analyses of primary carcinoma of the liver.
Hematoxylin and eosin (H-E) stained liver sections of 47 autopsy cases of hepatic malignancies were examined. There were 43 cases of hepatocellular carcinoma (subtypes of 30 trabecular, 7 solid, 5 pseudoglandular, and one scirrhous carcinoma), 3 of cholangiocellular carcinoma and one of mixed carcinoma. After immunohistochemical staining, benign hepatocytes reacted positively with anti-epithelial membrane antigen (EMA). Hepatocellular carcinoma cells reacted more weakly than benign hepatocytes. It was noted that the microtubular structure, which could not be demonstrated even by alcian blue or cationic ferric hydroxide colloid stabilized with cacodylate (Fe-CaC), was clearly detected with anti-EMA. The EMA-positive microtubular structures may indicate terminal cholangiolar differentiation. Based on EMA, seven more cases formerly classified as hepatocellular carcinoma by H-E were reclassified as mixed carcinoma, totaling eight (17.0%). The histologic classification of "mixed carcinoma" has been 1.5 to 2.0% of primary liver cancers in Japan, but we suggest there may be more cases of "mixed carcinoma" identified in the future. In conclusion, we emphasize that EMA staining is useful for more accurate classification of hepatic tumors.</p
Experimental Approach to Shielding and Reducing Effects on Ion Currents and Electric Fields at Earth Level under a DC Transmission Line
Use of a d. c. transmission line to find a way to reduce ion currents and electric fields at earth level is a most important matter for environmental safety. This paper discusses the relation between the ion currents and the electric fields at earth level, measured by using a unipolar d. c. transmission line scale model and a bipolar d. c. transmission line. Electric fields at earth level were calculated by means of the image charge method without taking into consideration the space charge caused by the d. c. line. The middle scale models for the unipolar and the bipolar d. c. lines were set at the height of the d. c. lines at 2m. Both types of scale models were set up in a sufficiently spacious room. Two small scales for the unipolar and the bipolar d. c. lines, with the height of the d. c. lines set at 20cm above the earth and the separating distance between the two d. c. lines set at 35 to 75cm, were placed in a suitable roomo. Both the experimental results are discussed here in comparison with the calculated fields. As a conclusion, in using the model unipolar d. c. line with a shielding wire, the shielding effects for both the electric fields and the ion currents at earth level nearly coincided with the calculated fields. However, in using the model bipolar d. c. lines, the reducing effect for the ion currents dind't coincide with the ealculated fields, actually not quite half of the calculated fields. In particular, the ion currents, at earth level on the positive voltage side were reduced very well, relative to those on the negative voltage side. They were measured in relation to the ratio of the separating distance of the bipolar d. c. lines to the the height of the d.c. line from earth level
Neural Fourier Transform: A General Approach to Equivariant Representation Learning
Symmetry learning has proven to be an effective approach for extracting the
hidden structure of data, with the concept of equivariance relation playing the
central role. However, most of the current studies are built on architectural
theory and corresponding assumptions on the form of data. We propose Neural
Fourier Transform (NFT), a general framework of learning the latent linear
action of the group without assuming explicit knowledge of how the group acts
on data. We present the theoretical foundations of NFT and show that the
existence of a linear equivariant feature, which has been assumed ubiquitously
in equivariance learning, is equivalent to the existence of a group invariant
kernel on the dataspace. We also provide experimental results to demonstrate
the application of NFT in typical scenarios with varying levels of knowledge
about the acting group
- …