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81.
Shuichi Seki Hiroki Sakaguchi Nobuyoshi Kawakita Atsushi Yanai Tetsuo Kuroki Kenzo Kobayashi 《Virchows Archiv : an international journal of pathology》1993,422(2):133-143
The proliferative activity and ultrastructural characteristics of proliferating biliary epithelial cells were analysed immunohistocytochemically in 39 biopsied liver specimens from patients with acute viral hepatitis, chronic hepatitis and liver cirrhosis using a monoclonal antibody against DNA polymerase (DNA-PA). In acute viral hepatitis with perivenular confluent necrosis, proliferation of typical bile ducts was found frequently in portal areas. In chronic aggressive hepatitis and cirrhosis, ductular proliferation of both typical and atypical forms was found in enlarged portal and periportal areas and in confluent necrotic areas. The number of proliferating biliary epithelial cells that stained positive for DNA-PA was small. There were very few positively stained cells in atypical bile ducts in confluent necrotic areas of cirrhosis. Atypical bile ducts seen in chronic aggressive hepatitis, cirrhosis and acute hepatitis with confluent necrosis were positively stained for both cytokeratins 8 and 19. In cirrhosis, the number of stained biliary epithelial cells in typical bile ducts was larger than the number of such cells in atypical bile ducts (P< 0.01). By electron microscopy, the cells positively stained for DNA-PA were mostly so-called clear cells with irregular nuclei containing coarse nucleoplasm, and a few small cells with scanty cytoplasm and few organelles. 相似文献
82.
Kuniaki Tanaka Yoshifumi Tomita Mari Tsuruta Fumiko Konishi Masao Okuda Kunisuke Himeno Kikuo Nomoto 《Immunopharmacology and immunotoxicology》1990,12(2):277-291
Chlorella vulgaris, an unicellular green algae, or its acetone-extract (Ac-Ex) were administered orally to Meth A tumor bearing BALB/c or (BALB/c DBA/2)F1 (CDF1) mice. When CDF1 mice were fed daily with 10% dried powder of Chlorella vulgaris (CVP) containing diet before and after Meth A tumor inoculation, the growth of rechallenged Meth A tumor was significantly suppressed in an antigen-specific manner. Augmentation of antitumor resistance was exhibited also by Winn assay using lymph node cells of tumor-bearing mice orally administered with CVP or Ac-Ex. Antigen-specific concomitant immunity in these mice were mediated by cytostatic T cells but not by cytotoxic T cells. Natural killer cells seemed not to contribute in antitumor resistance in this system. 相似文献
83.
Yasunari Nakamoto Shuichi Kaneko Masao Honda Masashi Unoura Jaehun Cheong Akihisa Harada Kouji Matsushima Kenichi Kobayashi Seishi Murakami 《Journal of medical virology》1994,42(4):374-379
The question was asked whether a predicted envelope protein, considered to be processed from the polyprotein precursor encoded by the putative E2/NS1 region of the hepatitis C virus (HCV) genome, may be observed in HCV-infected humans. Two polyclonal antibodies against recombinant E2/NS1 proteins were prepared and their reactivity tested against liver extracts from HCV-infected patients by immunoblotting analysis. A band corresponding to a size of 44 kDa was detected in liver extracts from patients who were positive for the HCV-specific antibody anti-C100-3 but not in liver extracts from patients who did not have anti-C100-3 antibody. Additionally, no band was detected using preimmune sera or antisera which had been preabsorbed with recombinant E2/NS1 proteins. Deglycosylation studies demonstrated that the 44 kDa protein was a glycosylated form of a 38 kDa protein which corresponds to the predicted molecular weight of the putative E2/NS1 protein. These results suggest that the 44 kDa protein is a product of the E2/NS1 region. Frequent observation of the 44 kDa band in cases of chronic active hepatitis C suggests a correlation between the expression of this protein and the progression of hepatitis. © 1994 Wiley-Liss, Inc. 相似文献
84.
Sazuku Nisitani Takeshi Tsubata Masao Murakami Tasuku Honjo 《European journal of immunology》1995,25(11):3047-3052
Activation mechanisms of B-1 (Ly-1 B) cells have been suggested to be different from those of conventional B cells. To assess the role of various interleukins (IL) in the activation of B-1 cells, we injected IL-4, IL-5 or IL-10 into nonanemic anti-red blood cells (RBC) autoantibody-transgenic mice, in which conventional B cells are clonally deleted but peritoneal B-1 cells persist without secreting Ig. Intraperitoneal or intramuscular injection of IL-5 or IL-10, but not IL-4, increased the number of antibody-producing peritoneal B-1 cells by four- to five-fold, resulting in increased anti-RBC serum autoantibody and induction of hemolytic anemia. These results suggest that IL-5 or IL-10 may play an important role in the terminal differentiation of B-1 cells into antibody-producing cells in vivo. 相似文献
85.
Nakashima Y Tagawa H Suzuki R Karnan S Karube K Ohshima K Muta K Nawata H Morishima Y Nakamura S Seto M 《Genes, chromosomes & cancer》2005,44(3):247-255
Natural killer (NK) cell lymphomas/leukemias are highly aggressive lymphoid malignancies, but little is known about their genomic alterations, and thus there is an urgent need for identification and analysis of NK cell lymphomas/leukemias. Recently, we developed our own array-based comparative genomic hybridization (array CGH) with an average resolution of 1.3 Mb. We performed an array CGH analysis for 27 NK-cell lymphoma/leukemia cases that were classified into two disease groups based on the World Health Organization Classification (10 aggressive NK-cell leukemia cases and 17 extranodal NK/T-cell [NK/T] lymphomas, nasal type). We identified the differences in the genomic alteration patterns of the two groups. The recurrent regions characteristic of the aggressive NK-cell leukemia group compared with those of the extranodal NK/T lymphoma, nasal-type group, were gain of 1q and loss of 7p15.1-p22.3 and 17p13.1. In particular, gain of 1q23.1-24.2 (P = 0.041) and 1q31.3-q44 (P = 0.003-0.047), and loss of 7p15.1-p22.3 (P = 0.012-0.041) and 17p13.1 (P = 0.012) occurred significantly more frequently in the former than in the latter group. Recurrent regions characteristic of the extranodal NK/T lymphoma, nasal-type group, compared with those of the other group were gain of 2q, and loss of 6q16.1-q27, 11q22.3-q23.3, 5p14.1-p14.3, 5q34-q35.3, 1p36.23-p36.33, 2p16.1-p16.3, 4q12, and 4q31.3-q32.1. Our results can be expected to provide further insights into the genetic basis of lymphomagenesis and the clinicopathologic features of NK-cell lymphomas/leukemias. 相似文献
86.
Yamaguchi K Nagano M Torada N Hamasaki N Kawakita M Tanaka M 《Rinsho byori. The Japanese journal of clinical pathology》2004,52(4):336-339
A novel urine tumor marker, diacetylspermine, was compared with two conventional serum tumor markers, carcinoembryonic antigen (CEA) (highly specific for pancreatic cancer) and carbohydrate antigen (CA) 19-9 (highly sensitive for pancreatic cancer), in 125 patients with bilio-pancreatic tumors. When the diagnoses of benign or malignant conditions were examined, the sensitivity of urine diacetylspermine (75%) was shown to be higher than that of CEA (44%; P = 0.044) and CA19-9 (75%). The specificity of urine diacetylspermine (81%) was lower than that of CEA (92%) and as high as that of CA19-9 (80%). These results suggest that urine discetylspermine is a highly sensitive and specific novel marker for bilio-pancreatic carcinoma. 相似文献
87.
Yukio Nagasaki Sang Bong Han Masao Kato Teiji Tsuruta 《Macromolecular chemistry and physics.》1992,193(7):1633-1641
Radical copolymerization of 4-(trimethylsilyl)styrene (TMSS) with styrene were carried out to estimate the reactivity of TMSS. The monomer reactivity ratios r1 and r2 in the radical copolymerization of TMSS (M1) with styrene (M2) were evaluated as 0,28 and 0,48, respectively. The value r1 · r2 (= 0,13) being smaller than unity indicates that the trimethylsilyl group at para position behaves as an electron-withdrawing substituent. Reactions of lithium diethylamide with TMSS in the presence of diethylamine, gave the 1:1 addition product 1-[2-(N,N-diethylamino)-ethyl]-4-(trimethylsilyl)benzene. Kinetic analysis showed that the second-order rate constant (k) for this addition reaction is 34,4 · 10?4 dm3 · mol?1 · s?1, which is by a factor of 2 larger than that for the reaction with styrene (k = 16,0 · 10?4 dm3 · mol?1 · s?1). The fact is also compatible with the above consideration for the r1 · r2 values. Lithium diisopropylamide initiated anionic copolymerizations of TMSS with 1,4-divinylbenzene (DVB) were also examined. The polymerizations proceed smoothly without any gel formation and the resulting copolymers are soluble in various common solvents such as benszene, tetrahydrofuran, chloroform, etc. Thus, novel organosilicon-containing polymers having appropriate amounts of reactive pendent vinyl groups are easily synthesized. 相似文献
88.
Keiji Nagai Yukihiko Ueno Nobuo Takamiya Masao Kaneko 《Macromolecular chemistry and physics.》1995,196(4):1241-1250
The photoluminescent Ru(bpy) complex was dispersed in a polysiloxane film containing 2,2′-bipyridine (bpy) pendant groups. The unusually long photoluminescence lifetime of the Ru(bpy) (1,94 μs at 25°C) and the blue-shifted photoluminescent wavelength suggest a rigid polymer matrix. The fluorescence yield becomes lower with higher probe concentration, indicating concentration quenching. According to the analysis based on Stern-Volmer plots, the quenching obeys a mechanism composed of both static and dynamic processes. A statistical intermolecular distance distribution between the probes was used to interpret the results in terms of static and dynamic quenching. It is shown that in the present system the dispersed complexes diffuse slightly during the excited state. 相似文献
89.
Sumiya Ganzorig Yuzaburo Oku Munehiro Okamoto Ramiro Malgor Masao Kamiya 《Parasitology research》1999,85(7):597-600
This report describes a new species of aspidoderid nematode, Ansiruptodera scapteromi sp. nov., the second species to be reported in the genus Ansiruptodera Skrjabin and Shikhobalova, 1947. The A. scapteromi sp. nov. is the first species of the genus to be recorded from a rodent host. The new species is clearly different from the only other species, A. ansirupta (Proença, 1937) Skrjabin and Shikhobalova, 1947, in that it possesses short lateral alae that terminate before the midbody; a smaller cephalic extremity; a shorter esophagus, pharynx, tail, and tail appendage; a smaller sucker; and longer spicules. The two species also differ in the numbers and arrangements of caudal papillae. A. scapteromi appears to be a parasite of capture and the water rats seem to have been infected from Edentata in Uruguay. 相似文献
90.
Lack of association between DNA base excision repair gene XRCC1 Gln399Arg polymorphism and risk of malignant lymphoma in Japan 总被引:2,自引:0,他引:2
Matsuo K Hamajima N Suzuki R Andoh M Nakamura S Seto M Morishimae Y Tajima K 《Cancer Genetics and Cytogenetics》2004,149(1):77-80
Growing evidence suggests that the polymorphism of DNA base excision repair gene XRCC1 Arg399Gln is associated with altered DNA repair proficiency and subsequent cancer susceptibility; however, no evidence is available for malignant lymphoma. We therefore conducted a case-control study (372 cases, 500 controls) to evaluate links with malignant lymphoma risk in Japan. The risk was evaluated in terms of odds ratio (OR) and 95% confidence interval (CI) adjusted for age and sex in an unconditional logistic regression model. There was no statistical risk change with the Arg/Gln (adjusted OR 0.89; 0.65-1.23, P = 0.492) or the Gln/Gln (0.57; 0.27-1.17, P = 0.127) compared with the Arg/Arg of the XRCC1 Arg399Gln polymorphism. The results were unchanged in analyses according to histological subtype (diffuse large lymphoma, follicular lymphoma, low-grade lymphoma of mucosa-associated lymphoid tissue, and others). These data suggest that XRCC1 Gln399Arg polymorphism plays a limited role in lymphomagenesis. Further study on the interaction between the polymorphism and environmental exposure is required. 相似文献