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21.
Although tumor cryosurgery would be expected to produce beneficial immunological effects from the enhancement of anti-tumor activity, under certain conditions the tumor may become enlarged and metastases promoted due to increased immunosuppressive activity and a high zone tolerance. In the present study, we examined whether hepatocyteproliferating factors were produced by the inoculation of freezing-thawing hepatic tissue (FTHT). Serum obtained from rats inoculated with FTHT increased DNA synthesis, according to measurement by [3H]thymidine incorporation in primary cultured rat hepatocytes. This increase was dependent on the serum concentration, with serum obtained on day 14 after the inoculation being the most potent for hepatocyte proliferation. The sensitized serum promoted DNA synthesis nearly as much as serum obtained from a 70% hepatectomized rat, but slightly less than 10ng/ml hepatocyte growth factor. The sensitized serum also protected hepatocytes from carbon tetrachloride (CCI4)-induced hepatotoxicity. Optical density measured by the 3-(4,5-dimethyl-thiazole-2-yl)-2,5-diphenyl tetrozolium bromide (MTT) cytotoxicity assay was increased, and the release of aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase in medium was decreased by treating hepatocytes damaged by CCI4 with the sensitized serum. These results suggest that certain hepatocyte-proliferating and protective factors are induced in serum by the inoculation of freezing-thawing hepatic tissue, and that the sensitized serum may be useful in the treatment of liver failure.  相似文献   
22.
Abstract: We have used heparin-bonded partial cardio-pulmonary bypass to support distal aortic circulation during aortic cross-clamping. However, there were no cardiotomy reservoirs with fully reliable thromboresistance. To resolve this problem, a short-acting anticoagulant (nafamostat mesilate) was added into a cardiotomy reservoir. The present study was designed to evaluate the efficacy of our distal perfusion system. From May 1995 through the end of May 1996, 27 patients underwent descending thoracic and thoracoabdominal aortic aneurysm repairs with this adjunct, 4 being excluded from the experiment. Twenty patients who had undergone conventional partial cardiopulmonary bypass were defined as the control group. There were no significant differences between the 2 groups in the morbidity, mortality, gas transfer, or transfusion requirements despite the fact that more complicated surgical procedures (shown by a two-fold increase in the prevalence of reoperation) were required in the group that had received the current distal perfusion adjunct. the heparin-bonded group. In conclusion, our perfusion system is very effective for descending thoracic and thoracoabdominal aortic aneurysm repairs.  相似文献   
23.
Lobular carcinoma of the male breast is very rare, because lobules do not exist in the male mammary gland. Seven cases of lobular carcinoma of the male breast have been reported in Europe and U.S.A., although no case in Japan. We encountered a very rare case of the lobular carcinoma of 74-year-old male breast. Histopathological examinations of both primary tumor and recurrent tumors of the skin led to the diagnosis of lobular carcinoma.  相似文献   
24.
25.
Two patients with "my hand" sign in association with tactile extinction from callosal lesion, one due to left anterior cerebral artery occlusion, the other due to right anterior cerebral artery aneurysm rupture, were reported. The examination of "my hand" sign was performed with the methods proposed by Brion et al. Our patients correctly responded when they grasped their own or the examiner's thumb with their left hand. But they replied "my finger"when they grasped not only their own but also the examiner's thumb with their right hand. Left tactile extinction was observed after a routine extinction test in one patient, and it was observed in the other after the following method: both patient's index fingers were disposed in his midline position. In these methods of extinction test, they made errors in saying "right" when both fingers were touched simultaneously. However, they said "both" when their right index finger alone was touched (synchiria) during an extinction test using the following method: both index fingers of patients were approached by examiner to touch each other or for one of them to touch the examiner's finger. When they were asked whose finger they touched in this method (whose finger test), they made the same errors as seen in "my hand" sign test. These test results suggest that there is a common underlying mechanism in the "my hand" sign and extinction, because the sense of double stimulations felt when only one stimulation is given (synchiria), is a possible explanation for the "my hand" sign and the pathogenesis of synchiria appears to be related to extinction.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
26.
A distinct subset of rat primary olfactory neurons was identified immunohistochemically by means of a polyclonal antibody against human placental antigen X-P2 (hPAX-P2), an incompletely characterized substance found in all estrogen-biosynthetic organs. The subset of olfactory receptor cells was distributed widely over the olfactory epithelium with some degree of concentration on the dorsocaudal walls of nasal subcavities. The subset formed unique "necklace olfactory glomeruli," which were composed of seven to nine solitary glomeruli located in the caudal end of the olfactory bulb. One of them was located in the "modified glomerular complex" reported to be involved in rat suckling behavior. The projectional patterns of the necklace olfactory system, albeit diffuse, indicated some degree of spatial correspondence between zones of olfactory epithelium and specific glomeruli. Axons emanating from neighboring cells can project to several glomerular loci. From the necklace olfactory system, an average of 150-200 receptor cells were estimated to converge onto a single necklace glomerulus.  相似文献   
27.
Recent data demonstrated that CD4+CD25+ regulatory T (Treg) cells and an enzyme called indoleamine 2,3-dioxygenase (IDO) mediate maternal tolerance to the fetus. Interestingly, Treg cells express the CTLA-4 molecule on their surface, and B7 (CD80/86) ligation by CTLA-4 enhanced IDO activity of dendritic cells (DCs) and monocytes by the induction of interferon gamma (IFN-gamma) production. In this study, we studied the IDO expression on peripheral blood monocytes and decidual monocytes or DCs after treatment with CTLA-4/Fc fusion protein or IFN-gamma using flow cytometry. IDO expressions on both peripheral blood DC and decidual DC and monocytes were up-regulated during normal pregnancy. On the other hand, both IDO expression on DC and monocytes after IFN-gamma treatment or CTLA-4 treatment were decreased in spontaneous abortion cases. The expression of CD86 on peripheral blood and decidual monocytes and DC in spontaneous abortion cases was lower compared with those in normal pregnancy subjects. Also, IFN-gamma production by decidual and peripheral blood mononuclear cells after CTLA-4/Fc treatment in spontaneous abortion cases was significantly lower than those in normal pregnancy subjects. These data suggest that CTLA-4 on Treg cells up-regulates IDO expression on decidual and peripheral blood DC and monocytes by the induction of IFN-gamma production.  相似文献   
28.
Chromophobe renal cell carcinoma (RCC) is a recently established subtype of RCC, which has rarely been reported in Japan. In this communication, the authors report two Japanese cases of chromophobe RCC together with the immunohistochemical findings. The tumors were composed of sheets and cribriform glands formed by tumor cells with cloudy and reticular cytoplasm. Ultrastructurally, the cytoplasm was filled with numerous microvesicles. The tumor cells were positive for cytokeratin, epithelial membrane antigen, and Tamm-Horsfall protein. Occasionally, LeuM1-positive cells were also noted. Vimentin was negative, unlike the usual RCC. Reactivity for peanut agglutinin was more frequent than that to Lotus tetragonolobus agglutinin. The results of this study suggest that the tumor cellq possessed phenotypes similar to the distal nephron rather than to the proximal tubular cells.  相似文献   
29.
The exposure of human lymphoid leukemia Molt 4B cells to sesaminol, a component of sesame oil led to both growth inhibition and the induction of apoptosis. Morphological change showing apoptotic bodies was observed in the cells treated with sesaminol. The fragmentation of DNA by sesaminol to oligonucleosomal-sized fragments that are characteristics of apoptosis was observed to be concentration- and time-dependent. These findings suggest that growth inhibition of Molt 4B cells by sesaminol results from the induction of apoptosis in the cells.  相似文献   
30.
A genomic subtraction between a pandemic Vibrio parahaemolyticus and a nonpandemic strain that seemed to be clonally related was performed. A subtractive DNA fragment was identified to be a part of a 16-kbp insertion sequence which was present in almost all pandemic strains but not in nonpandemic strains tested.  相似文献   
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