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41.
Molecular investigation of 16 strains, conventionally identified to be Malassezia pachydermatis, isolated from dogs in Japan was carried out by random amplification of polymorphic DNA (RAPD) and chitin synthase 2 (CHS2) gene sequence analyses. The RAPD band patterns of 13 clinical isolates were identical to that of standard strain of M. pachydermatis (CBS-1879). The other three clinical isolates were different from the standard strain of M. pachydermatis in RAPD patterns, and two of the three isolates were identical. About 620 bp genomic DNA fragments of the CHS2 gene were amplified from the same 16 clinical isolates of M. pachydermatis by polymerase chain reaction (PCR) and sequenced. The phylogenetic analysis of the nucleotide sequences of CHS2 gene fragments of the 16 clinical isolates revealed that the 13 strains were genetically very close to the standard strain of M. pachydermatis and the other two isolates were genetically close to the standard strain of M. furfur rather than M. pachydermatis. The remaining one isolate was phylogenetically distinct from all the seven Malassezia species reported so far.  相似文献   
42.
Recent studies on the cytoskeleton of osteoblasts have been made mainly using cultured cells. However, the morphology of cultured cells may be altered during subculture. Therefore, cytoskeletal changes of calvarial osteoblasts were investigated in situ by electron microscopy using the detergent perfusion method to preserve cell morphology as well as selectively observing the cytoskeleton in the presence of a high concentration of prostaglandin E2 (PGE2) in the calvarial periphery in rats. Rats were perfused with a mixture of Triton X-100 and glutaraldehyde, then the cytoskeleton was observed by transmission electron microscopy. In osteoblasts of the control group, thick bundles of microfilaments ran parallel to the long axis of the cells immediately below the cell membrane adjacent to the osteoid layer. In contrast, in the osteoblasts of the PGE2-administered group, the external morphology was changed to an asteroid or cubic shape, and thick bundles of microfilaments immediately below the cell membrane adjacent to the osteoid were not observed, although microfilament fibres, with a diameter of 5-6 nm, were observed in the cytoplasm.  相似文献   
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Enamel matrix protein (EMP) was applied for regeneration of periodontal tissue in 2 dogs with spontaneous periodontal disease. Case 1 had bony resorption around the root and root apex of the maxillary fourth premolars. Case 2 had vertical resorption of bone between the mandibular first and second molars. A flap was formed in the buccal gingiva, and EMP was applied onto the surface of the exposed root. One or 4 months postoperatively, increased bone level and clinical attachment were recognized. EMP was therefore suggested to be effective to induce regeneration of periodontal tissues in the cases with periodontal disease.  相似文献   
47.
Nineteen analogues were synthesized by modifying the tert-butylhydrazine moieties of N'-tert-butyl-N'-(3,5-dimethylbenzoyl)-5-methyl-2,3-dihydro-1,4-benzodioxine-6-carbohydrazide and N'-tert-butyl-N'-(3,5-dimethylbenzoyl)-5-methylchromane-6-carbohydrazide (chromafenozide), and the synthesized analogues were evaluated for their insecticidal activity against Spodoptera litura F. While all of the synthesized analogues had insecticidal activity inferior to those of the lead compounds, several of the analogues nonetheless showed high insecticidal activity. Chromafenozide has shown very high selectivity toward lepidopteran species.  相似文献   
48.
A new chemolytic therapy with amino acid preparation was tried for use on struvite renal stones in two dogs, which were admitted to Azabu University Veterinary Teaching Hospital. No other special diet, for the purpose of dissolving the stones, was fed during the treatment. Dissolution of the stones began at week 1, and no stone was detected on radiography at week 4 in both cases. The amino acid preparation thereafter has been administered every 2-3 days to prevent formation of the stones. After 6 months from treatment, complete dissolution was confirmed, and no relapse has been observed. Therefore, it is concluded that chemolytic therapy with amino acid preparation might be useful for the treatment of nephrolithiasis with struvite renal stones in dogs.  相似文献   
49.
ABSTRACT The presence of mulberry dwarf (MD) phytoplasmas in organs of the inoculative vector insects Hishimonoides sellatiformis and Hishimonus sellatus was determined by means of electron microscopy (EM) and polymerase chain reaction (PCR) assays. Many MD phytoplasmas were detected in genital organs as well as in the intestines, salivary glands, brains, fat bodies, and thoracic ganglia of Hishimonoides sellatiformis, but only in the intestine and salivary glands of Hishimonus sellatus. Many phytoplasmas with characteristic morphology were observed via EM in ovaries, seminal receptacles, and testes, and they were further identified by PCR assays with group I-specific primers. In addition, the organisms were detected by direct or nested PCR assays in eggs (head pigmentation stage of embryos) laid on mulberry shoots by inoculative leafhoppers and in the newly hatched nymphs from these eggs. These findings indicate that transovarial transmission of MD phytoplasmas occurs in Hishimonoides sellatiformis.  相似文献   
50.
There have been diverse reports on the effects of diazepam on cardiac contractility. The purpose of this study was to examine whether diazepam modifies the inotropic response elicited by histamine on an isolated guinea-pig papillary muscle. The responses of electrically driven papillary muscle to histamine and cyclic AMP-related inotropic agents were recorded in the absence and in the presence of diazepam. Histamine and forskolin, which directly stimulate adenylate cyclase, significantly increased the contractile force in the papillary muscle in a concentration-dependent manner. A histaminergic H2-receptor antagonist, cimetidine, but not a H1-receptor antagonist, diphenhydramine, at 10 μ M produced a rightward shift in the concentration-response curve for histamine. Diazepam (10 μ M ) shifted the concentration-response curve for histamine and forskolin to the left by 1.8 and 1.6 times, respectively. Neither a central type (fulmazenil) nor a peripheral type (PK11195) of benzodiazepine receptor antagonist modified the effect of diazepam on the histaminergic-evoked contraction. Phosphodiesterase blockade by 3-isobutyl-1-methylxanthine shifted the concentration-dependent curve for histamine to the left. A combination of 3-isobutyl-1-methylxanthine also produced a leftward shift of the curve. However, there was no significant difference between the 3-isobutyl-1-methylxanthine only group and the combination group. These results indicate that diazepam potentiates the positive inotropic effect produced by histamine, probably mediated via an increase in cyclic AMP levels induced by histamine.  相似文献   
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