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41.
Excretory-secretory (ES) products collected from adult Dirofilaria immitis cultured in vitro were analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting. ES products of male (M-ES) and female (F-ES) worms were separated into 16 and 21 bands by SDS-PAGE with Coomassie blue and silver staining, respectively. The antigenic bands were then analyzed by immunoblotting, using pooled sera from dogs that had naturally contracted D. immitis. Sera from dogs with microfilaremic infection showed 7 bands in M-ES and 10 bands in F-ES, while those from dogs with occult infection revealed 3 bands in M-ES and 10 bands in F-ES. Among these bands, those of 14, 18, 21, 22, 29, and 32 kilodaltons (Kd) were common to M-ES and F-ES, those of 39 and 44 Kd were specific to M-ES, and those of 20, 38, 43, 53, 63, 90, 110, 125 and 136 Kd were specific to F-ES.  相似文献   
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Although gpt delta rats, as reporter gene-transgenic rats, were originally developed for in vivo mutation assays, they have also been used to evaluate chemical carcinogenesis and comprehensive toxicity. Therefore, it is necessary to accumulate background data on carcinogenicity and general toxicity in gpt delta rats. Here, we investigated the background data of 110-week-old male and female F344 gpt delta rats and wild-type rats. There was no effect of reporter gene transfection on animal survival rates and body weights during the experiment. The relative weight of male gpt delta rat adrenals was significantly higher than that of wild-type rats, possibly due to the higher incidence of pheochromocytoma. There were no intergenotype differences in the incidence of nonneoplastic lesions in both sexes, including chronic progressive nephropathy and focus of cellular alteration in the liver, which had a higher incidence in both genotypes. Additionally, the significantly higher incidence of adrenal pheochromocytoma in male gpt delta rats than that in wild-type rats was likely incidental because of the lack of differences in the incidences of preneoplastic (male and female) and neoplastic (female) adrenal lesions in both genotypes. Other neoplastic lesions in both sexes showed no intergenotype differences in incidence rates, although large granular lymphocytic leukemia in the spleen and Leydig cell tumors in the testes of males showed higher incidence rates. Overall, there were no effects of reporter gene transfection on the spectrum of spontaneous lesions in F344 gpt delta rats, thus supporting their applicability in evaluating chemical toxicity and carcinogenicity.  相似文献   
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A mass developed in the mandibular gingiva of a thoroughbred racehorse. When the horse could no longer eat unassisted, it was killed and immediately autopsied. Macroscopically, the mandible exhibited extensive osteolysis, with only a small amount of bone remaining around the tooth roots. The cut surface of the mass around the mandible consisted of neoplastic medullary tissue, in which osteogenesis was observed. The medullary tissue was composed of pleomorphic medium-sized to large cells, interlaced by collagen bundles. These cells had large, pale, round or ovoid, sometimes cleaved nuclei, with one or two prominent nucleoli. Mitoses were numerous. Electron microscopy showed that the cells in the medullary tissues were similar in shape to undifferentiated lymphocytes. Immunohistochemically, these cells were positive for B-cell associated antigen in the pre-B-cell stage. Our findings suggest that the horse had extranodal lymphoblastic lymphoma of suspected B-cell lineage, possibly originating from the lymphatic system of the gingiva. We consider that the osteolysis resulted from activation of osteoclasts by proliferation of the tumour cells.  相似文献   
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Regolith particles on the asteroid Itokawa were recovered by the Hayabusa mission. Their three-dimensional (3D) structure and other properties, revealed by x-ray microtomography, provide information on regolith formation. Modal abundances of minerals, bulk density (3.4 grams per cubic centimeter), and the 3D textures indicate that the particles represent a mixture of equilibrated and less-equilibrated LL chondrite materials. Evidence for melting was not seen on any of the particles. Some particles have rounded edges. Overall, the particles' size and shape are different from those seen in particles from the lunar regolith. These features suggest that meteoroid impacts on the asteroid surface primarily form much of the regolith particle, and that seismic-induced grain motion in the smooth terrain abrades them over time.  相似文献   
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Oxygen isotopic composition of our solar system is believed to have resulted from mixing of two isotopically distinct nebular reservoirs, 16O-rich and (17,18)O-rich relative to Earth. The nature and composition of the (17,18)O-rich reservoir are poorly constrained. We report an in situ discovery of a chemically and isotopically unique material distributed ubiquitously in fine-grained matrix of a primitive carbonaceous chondrite Acfer 094. This material formed by oxidation of Fe,Ni-metal and sulfides by water either in the solar nebula or on a planetesimal. Oxygen isotopic composition of this material indicates that the water was highly enriched in 17O and 18O (delta(17,18)O(SMOW) = +180 per thousand per mil), providing the first evidence for an extremely (17,18)O-rich reservoir in the early solar system.  相似文献   
48.
茉莉花中芳樟醇生成相关酶的精制   总被引:10,自引:0,他引:10  
从酶学角度探讨了茉莉花重要香气成份芳樟醇的 生成机理⒚以双瓣茉莉花为材料,经过调制丙酮粉,缓冲液粗提,20% ~80% 饱和度硫铵分部, C M  Toyopearl 650 M 和 F P L C C M  Toyopearl 650 S两次柱层析,得到了 F C 蛋白分部液⒚同时经 G C M S 定性和 G C 定量分析,明确 F C 部分是催 化茉莉花粗 香气前 体物 质生 成芳 樟醇 的主 要部分⒚进 一步 经等 电电 泳、β D葡萄 糖苷 酶活 性染色 等电 电泳 和 S D S P A G E 凝胶电泳,初步判断 β D葡萄糖苷酶参与了芳樟醇的生成,且该酶的等电点在 8.7~9.0,其单体蛋白的分子量在 35~38 k D 之间 ⒚  相似文献   
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Mongrel dogs were inoculated with two kinds of antigenic substances. The first was a phosphate buffered saline extract of whole Dirofilaria immitis mixed with aluminum hydroxide gel (group 1), and the second was an orally administered live Metastrongylus apri infective larvae (L3) (group 2). Both groups were then infected with D. immitis L3. Indirect hemagglutination (IHA) tests showed that the antibody was produced by these inoculations before the infection was introduced, even in dogs inoculated with M. apri. This suggests a cross-reactivity between D. immitis and M. apri. The initial passive cutaneous anaphylaxis (PCA) antibody production was markedly delayed by about 70 days in group 2 compared with the production in the infected control dogs (group 3). The appearance of microfilaremia was also delayed by about one month in group 2 compared with that in the above control group. All dogs were sacrificed after the termination of the observation and worms recovered from the right ventricle and pulmonary arteries were counted and measured. The results indicated that immunization resulting from the homologous worm-somatic antigen might accelerate the growth of the infected larvae, whereas immunization resulting from the heterologous worm antigen, but cross-reactive to D. immitis, might disadvantageously affect the growth.  相似文献   
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