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51.
Antinephritis and radical scavenging activity of prenylflavonoids   总被引:4,自引:0,他引:4  
Fukai T  Satoh K  Nomura T  Sakagami H 《Fitoterapia》2003,74(7-8):720-724
Antinephritis activity of 5 prenylflavonoids similar to glabridin (1-5), isolated from Morus alba, Artocarpus communis, Glycyrrhiza uralensis and G. inflata, was evaluated in mice with glomerular disease (Masugi-nephritis). Oral administrations of artonin E (2) or licochalcone A (4) for 10 days (30 mg kg(-1) day(-1)) reduced the amount of urinary protein excretion compared to nephritic mice. ESR spectroscopy demonstrated that morusin (1) and licorisoflavan A (5) increased the radical intensity of sodium ascorbate by about two times. Morusin, licoricidin (3), licochalcone A and licorisoflavan A showed weak scavenging activity against superoxide anion radical.  相似文献   
52.
A 9-year-old, castrated male Japanese domestic cat presented with a complaint of exertional dyspnea. Based on the radiographic findings, presumptive diagnosis of aspiration pneumonia or primary diffuse pulmonary neoplasia in the right middle lobe was made. Histologically, the pulmonary lesion was characterized by diffuse thickening of alveolar wall with the proliferation of apparently atypical irregular-shaped cells. Immunohistochemical staining using anti-human factor VIII-related antigen antiserum showed positive reaction in the cytoplasm of the atypical cells. According to the findings, the lesion was diagnosed as pulmonary intravascular hemangiosarcoma.  相似文献   
53.
Plants have evolved a powerful immune system to defend against infection by most microbial organisms. However, successful pathogens, such as Pseudomonas syringae, have developed countermeasures and inject virulence proteins into the host plant cell to suppress immunity and cause devastating diseases. Despite intensive research efforts, the molecular targets of bacterial virulence proteins that are important for plant disease development have remained obscure. Here, we show that a conserved P. syringae virulence protein, HopM1, targets an immunity-associated protein, AtMIN7, in Arabidopsis thaliana. HopM1 mediates the destruction of AtMIN7 via the host proteasome. Our results illustrate a strategy by which a bacterial pathogen exploits the host proteasome to subvert host immunity and causes infection in plants.  相似文献   
54.
H9N2 influenza viruses circulate in wild birds and poultry in Eurasian countries, and have been isolated from pigs and humans in China. H9N2 viruses isolated from birds, pigs and humans have been classified into three sublineages based on antigenic and genetic features. Chicken antisera to H9N2 viruses of the Korean sublineage reacted with viruses of different sublineages by the hemagglutination-inhibition test. A test vaccine prepared from a non-pathogenic A/duck/Hokkaido/49/1998 (H9N2) strain of the Korean sublineage, obtained from our influenza virus library, induced immunity in mice to reduce the impact of disease caused by the challenge with A/Hong Kong/1073/1999 (H9N2), which is of a different sublineage. The present results indicate that an inactivated whole virus vaccine prepared from a non-pathogenic influenza virus from the library could be used as an emergency vaccine during the early stage of a pandemic caused by H9N2 infection.  相似文献   
55.
The occurrence of morphological deformities under different rearing water temperatures (18, 20, 22, 24, 26, 28, and 30 C) was examined in Japanese eel larvae. The rates of hatching and survival until yolk resorption at 22–26 C were higher than those at other water temperatures. Fertilized eggs never hatched at 18 and 30 C. The rates of occurrence of abnormal larvae reared at the water temperatures 24–28 C were lower than those at 20 or 22 C. Pericardial edema and lower jaw deformities occurred most frequently at lower temperatures (20 and 22 C). In contrast, the incubation temperature did not significantly affect the relative frequency of some neurocranial deformities and of spinal curvature. These results imply that the optimal temperatures for rearing Japanese eel eggs and embryos are 24–26 C from the viewpoints of survival and deformity.  相似文献   
56.
Canine deciduoma could be induced in the diestrous uterus by an intrauterine inoculation of a culture suspension of E. coli originally isolated from naturally occurring canine pyometra. These deciduomas had the same histological findings as those of naturally occurring canine pyometra with so called "Swiss cheese endometrium". This suggests a possibility that the canine pyometra is a kind of naturally occurring decidual reaction (deciduoma) induced by one of several triggers such as bacterial infection.  相似文献   
57.
In the Japanese Black cattle population, five genetically divergent subpopulations have played important roles as suppliers of breeding stocks to the entire breed. We supposed a situation where five lines were constructed from each of the five subpopulations, and applied to this set of lines a management plan to conserve genetic diversity. Assuming that the male migration pattern among the lines followed the island model, we assessed the optimum male migration rate and required male numbers in each line, satisfying the following three conditions simultaneously: (i) the rate of inbreeding in each line was below 0.01 per generation; (ii) at least 97% of the initial genetic diversity was preserved after 10 generations; and (iii) more than 50% of the genes in an initial line were retained in the line after 10 generations. We found that approximately one breeding male should be selected per year and one breeding male should be exchanged among the lines per generation in each line to satisfy these three conditions. Numerical analysis with the migration rates actually observed among the five subpopulations demonstrated that the initial genetic differentiation among the lines was rapidly decayed by an asymmetrical migration pattern. For a successful plan, migration among lines should be strictly managed.  相似文献   
58.
Mast cell tumors (MCTs) of gastrointestinal origin that had been surgically removed from 39 dogs were examined to evaluate their pathologic features. Miniature breeds, especially Maltese, were most frequently affected. The average age of affected dogs was 9.7 +/- 2.6 years. No sex difference was apparent. The most frequently affected sites were in the upper digestive tract, and the prognosis was very poor. Grossly, the gastrointestinal wall was prominently thickened, and the lumen of the affected gut was usually narrowed. Microscopically, there was diffuse transmural invasion of round to pleomorphic tumor cells. Tumor cells had moderate to abundant cytoplasm, round to ovoid nuclei with scattered chromatin, and mitotic figures. Fibrous stroma was observed in about half of the tumors. There was variable infiltration of eosinophils. In all tumors, cytoplasmic granules showed weak metachromasia, but the number of granules was very small. Immunohistochemical staining for c-kit and mast cell tryptase was positive in 77% and 62% of tumors, respectively. All tumors were positive for at least two of these markers. Immunohistochemical staining for p53 was positive in 13% of the tumors. Reactivity for staining markers and p53 was unrelated to cell pleomorphism, vessel invasion, or survival time. Gastrointestinal MCTs have histologic and immunohistochemical features completely different from those of other primary or metastatic gastrointestinal tumors. The combination of immunostaining for mast cell tryptase and c-kit and histochemical staining for metachromasia appears to be a powerful tool for the diagnosis of gastrointestinal MCTs.  相似文献   
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