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EE Tseng MV Brock MS Lange JC Troncoso ME Blue CJ Lowenstein MV Johnston WA Baumgartner 《Canadian Metallurgical Quarterly》1998,124(2):298-306
BACKGROUND/AIM: A herbal medicine, Sho-saiko-to (TJ-9), has recently been orally administered to patients with chronic liver disease in Japan and has been reported to inhibit the development of hepatocellular carcinoma. The aim of this study was to investigate whether TJ-9 has an inhibitory effect on the development of preneoplastic lesions and liver fibrosis in rats. METHODS: The effects of the TJ-9 were examined using the choline-deficient L-amino acid-defined (CDAA) diet-induced liver fibrosis model in 16-week-old male Wistar rats. RESULTS: TJ-9 (1% w/w) prevented fibrosis, as indicated by reduced hydroxyproline content in the liver and inhibition of the increase in a serum marker of fibrosis (hyaluronic acid), without reducing the increase in serum alanine aminotransferase and aspartate aminotransferase. TJ-9 also reduced the expression of type III procollagen alpha 1 mRNA in the liver, as well as the proliferation of myofibroblast-like cells (activated stellate cells, activated Ito cells). Furthermore, TJ-9 reduced the number of preneoplastic lesions, detected as enzyme-altered (glutathione S-transferase placental form-positive) lesions, in the liver. CONCLUSIONS: These results indicate that the herbal medicine Sho-saiko-to (TJ-9) prevents fibrosis as well as preneoplastic lesions, not by inhibiting hepatocyte cell death but by inhibiting the activation of stellate cells, which are considered to be the main collagen-producing cells, leading to a reduction in the development of preneoplastic lesions. 相似文献
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IV Kartavtseva MV Pavlenko VA Kostenko FB Cherniavski? 《Canadian Metallurgical Quarterly》1998,34(8):1106-1113
G-banding and C-banding of chromosomes were studied in populations of the red-backed mouse Clethrionomys rufocanus from 11 localities of eastern Russia. Intrapopulation polymorphism of autosome 3 caused by the deletion-duplication of the short-arm heterochromatin (2n = 56; NFa = 56-58) was demonstrated. The karyotype of Cl. rufocanus from continental populations and Sakhalin Island was shown to have a large subtelocentric chromosome of pair 3 (NFa = 58), whereas in the population from Kunashir Island, chromosomes of this pair were acrocentric (NFa = 56). One animal from the population of the Kedrovaya Pad' Reserve (Primorsk krai) had a pericentric inversion (acrocentric morphology) of the Y chromosome. In two animals, a female from the Ussuriiskii Reserve (Primorsk krai) and a male captured near the Tomari Settlement (Sakhalin Island), a pericentric inversion of one chromosome of pair 6 was found (NFa = 59). The inversion detected in the animal from the Sakhalin population was accompanied by the loss of the centromeric heterochromatin. In contrast, the inversion of the chromosome pair 6, which was found in the mouse from the Primorsk krai population, did not involve the loss of centromeric heterochromatin. Analysis of our results and data from the literature showed that the karyotype of Cl. rufocanus is not constant, as was thought earlier. The percentage of animals with abnormal karyotype (1.6%) was higher than in other groups of red-backed mice studied (0.12-0.7%). 相似文献
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Pancreatic islets prelabelled with either 86Rb or 45Ca were exposed to a rise in D-glucose concentration from 2.8 to 16.7 mM whilst perifused in the presence of 2 microM glibenclamide, 30 mM extracellular K+ and both 30 mM K+ and 250 microM diazoxide. In all three situations, the rise in glucose concentration provoked a dramatic increase in insulin output, despite unchanged or even increased efflux of 86Rb from the prelabelled islets. Also in all three situations, glucose sharply decreased effluent radioactivity from islets prelabelled with 45Ca but perifused in the absence of extracellular Ca2+, while augmenting 45Ca efflux, to a variable extent, from islets perifused at normal extracellular Ca2+ concentration (1.0 mM). It is proposed, therefore, that the insulinotropic action of D-glucose in depolarized islets, and presumably also under normal conditions, may involve the gating of voltage-insensitive Ca2+ channels. 相似文献
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Dermatoglyphic patterns in patients with mitral valve prolapse: a clue to pathogenesis 总被引:1,自引:0,他引:1
Fingerprints were obtained from 100 patients with mitral valve prolapse and compared with those of 100 control subjects matched for sex and race. Arches were found in 16.8 percent of all digital patterns in patients with mitral valve prolapse but in only 2.5 percent of all digits in the control group. Whereas no patient in the control group had four or more arches, 19 percent of patients with mitral valve prolapse had this finding. In addition, arches were found on 16 and 9 percent, respectively, of digits IV and V in patients with mitral valve prolapse but were not found on these digits in the control group. The finding of four or more arches or arches on digits IV or V may be important supportive evidence of mitral valve prolapse when evaluating patients with atypical chest pain and palpitations. Antenatal factors may be involved in the pathogenesis of mitral valve prolapse since it is possible that a genetic or environmental factor that interferes with the development of the mitral valve may also influence epidermal ridge patterns. 相似文献
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