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41.
42.
Nickel subsulfide (Ni3S2) is known to induce intraocular neoplasms when injected intravitreally into the eyes of rats. Here, we found two extraocular orbital neoplasms in two different rat strains, presumably due to the leakage of locally injected Ni3S2 to the extraocular orbital tissues. In the F344/DuCrlCrlj rat, an orbital mass arose at 30 weeks after injection, and invaded into the cranium. Histologically, the orbital mass was composed of areas arranged in parallel bundles formed by densely packed elongated or spindle-shaped cells with indistinct cytoplasmic borders, and of areas of hypocellular arrangement consisting of round cells in eosinophilic myxoid-like substances. Metastases were observed in the right submandibular and cervical lymph nodes. The neoplastic cells were immunopositive for S-100 protein and vimentin. Transmission electron microscopy revealed that the neoplastic cells had cellular processes and pericytoplasmic basal laminae. In the RccHanTM:WIST rat, an orbital mass arose at 36 weeks after injection. Histologically, the mass consisted of rhabdoid-like large round cells with proliferation of small round-to-polygonal cells, and these neoplastic cells infiltrated into the extraocular muscles. Immunohistochemically, the neoplastic cells were positive for desmin and vimentin. Transmission electron microscopy detected immature myofibrils with Z-band structures in the cytoplasm of these neoplastic cells. Consequently, the tumors were diagnosed as an orbital malignant schwannoma in an F344/DuCrlCrlj rat and an orbital embryonal rhabdomyosarcoma in a RccHanTM:WIST rat. The results of this case report suggest that leakage of Ni3S2 to the orbit caused the induction of orbital malignant schwannoma or rhabdomyosarcoma in rats.  相似文献   
43.
Antifungal activity was detected from Anemarrhena asphodeloides by the Bio-Cell Tracer (BCT) method. An active fraction was separated by silica gel column chromatography and reverse-phase HPLC. The molecular weight was determined by GC-MS, and the molecular structure was analyzed by IR, (1)H NMR, and (13)C NMR. The isolated compound was found to be identical to nyasol, (Z)-1, 3-bis(4-hydroxyphenyl)-1,4-pentadiene, which formerly appeared in the literature without any remark on the antifungal activity. This compound showed antimicrobial activity against 38 strains of fungi and five strains of bacteria. The minimum inhibitory concentration (MIC) ranged from 12.5 to 200 microg mL(-)(1), except for two strains based on the broth dilution method.  相似文献   
44.
An enzymatic hydrolysate of wheat gluten was further digested in vitro with porcine pepsin and pancreatin to obtain an indigestible peptide. Indigestible pyroglutamyl peptide was isolated from the digest by strong cation-exchange, size-exclusion, and reversed-phase chromatographies. The pyroglutamyl peptide was digested with pyroglutamate aminopeptidase, and the digest was reacted with phenyl isothiocyanate. The resultant phenylthiocarbamyl (PTC) peptides were purified by reversed-phase HPLC by using binary gradient elution with ammonium acetate buffer, pH 6.0, and acetonitrile. The PTC peptides were analyzed with an automatic peptide sequencer on the basis of the Edman degradation method with a modified program. Some pyroglutamyl peptides were also analyzed by fast-atom bombardment ionization mass spectrometry without the pyroglutamate amino peptidase digestion. Consequently, pyroGlu-Asn-Pro-Gln, pyroGlu-Gln-Gln-Pro-Gln, pyroGlu-Gln-Pro-Gln, pyroGlu-Gln-Pro-Gly-Gln-Gly-Gln, pyroGlu-Gln, pyroGlu-Gln-Pro, pyroGlu-Ile-Pro-Gln, pyroGlu-Ile-Pro, pyroGlu-Gln-Pro-Leu, pyroGlu-Gln-Phe-Pro-Gln, pyroGlu-Ser-Phe-Pro-Gln, pyroGlu-Phe-Pro-Gln, and pyroGlu-Gln-Pro-Pro-Phe-Ser were identified.  相似文献   
45.
ABSTRACT:   Artificially hatched Seriola species have the problem of malformation, mainly in their vertebrae, head, and mouth parts. To clarify the cause of vertebral malformation, the effects of hypoxia during embryogenesis on the induction of centrum defects was investigated in artificially hatched amberjack Seriola dumerili . Firstly, 7-somite stage embryos were exposed to waters of 0, 12.5, 25, 50, and 100% dissolved oxygen (DO) for 0.5, 1, 2, 3, 4, and 5 h to confirm the effective dose (DO concentration and duration of exposure) of hypoxia that induces somitic disturbances in newly hatched larvae. Exposure of embryos to 12.5% DO concentration for longer than 0.5 h induced somitic disturbances. Following this result, centrum defects in juveniles were investigated by an induction experiment with embryos exposed to 12.5% DO for 2 h at the gastrula, 1- or 2-somite, 10-somite, 15-somite, or heart beating stage. This experiment revealed that centrum defects were induced only during somitogenesis, and somitic disturbances were the premonitory symptom of centrum defects. These results indicate hypoxia during somitogenesis as a possible cause of centrum defects in amberjack.  相似文献   
46.
Wild relatives genetically close to cultivars are precious genetic resources for plant breeding. Oryza rufipogon, O. barthii, O. glumaepatula, O. meridionalis and O. longistaminata are such wild species, and are also categorized as AA genome species based on their structural similarities. Chromosome segment substitution lines (CSSLs) are a powerful resource in breeding and genetics, and numerous rice CSSLs have been produced. This study aimed to develop DNA markers for evaluation of CSSLs directly by PCR and subsequent gel electrophoresis. We confirmed that up to 155 of 188 markers developed for detection of japonica-indica INDELs could also detect INDELs between rice cultivars and wild AA-species accessions. Percentages of applicable markers were higher in O. rufipogon accessions (61.7 to 85.6%), and lower in accessions of other four AA species (39.8 to 51.4%). These markers were distributed throughout the rice chromosomes, and will be useful for genotyping of CSSLs and other genetic resources derived from crosses between rice cultivars and closely related wild species.  相似文献   
47.
To clarify the genetic properties of the HMW glutenin subunit composition of Asian endemic wheats, SDS–PAGE analysis was conducted using 1,139 bread wheat accessions that were originally collected in Asia. The samples were divided into six regional groups, Western Asia, Caucasia, Central Asia, Afghanistan, Southern Asia, and Eastern Asia. The genotype Glu-A1c, Glu-B1b, and Glu-D1a encoding subunits null, 7+8, and 2+12 had an overall frequency of 55.2%. Thus, we conclude that it is the typical genotype of the HMW glutenin subunits that characterize Asian endemic wheat. The frequency of the typical Asian genotype was relatively high in the central belt of Asia (Western Asia, Afghanistan, and Eastern Asia) and low in the marginal regions (Caucasia, Central Asia, and Southern Asia). In Southern Asia, the frequency of Glu-B1i, which encodes subunit 17+18, was the highest at the Glu-B1 locus. In Caucasia and Central Asia, the frequency of Glu-D1d, which encodes subunit 5+10 (which is considered to be the most useful for making bread), was high. The level of genetic variation, as estimated using the frequencies of the various alleles, was relatively low in the central belt of Asia and high in the marginal regions. Among the three Glu-1 loci, the highest number of alleles was detected at the Glu-D1 locus. This result was caused by the presence of rare Asian specific alleles at the Glu-D1 locus, in which a newly found allele, Glu-D1bs, encoding subunit 2.1+12 was included.  相似文献   
48.
1,5-anhydro-D-glucitol (1,5AG) is a pyranoid polyol compound found in human circulating blood. Myo-inositol (MI) is a stereoisomer of inositol and serves as a precursor of inositol phospholipids. 1,5AG and MI are filtered by the glomerulus and almost completely reabsorbed through the renal tubules. However, under hyperglycemic conditions, reabsorption through the renal tubules is competitively inhibited because the structures of 1,5AG and MI resemble that of glucose. In this study, we investigated the kinetics of serum and urine 1,5AG and MI levels in healthy dogs. We demonstrated that 1,5AG and MI exist in canine serum and urine by gas chromatography-mass spectrometry. Under continuous hyperglycemic conditions, the serum 1,5AG concentration in healthy dogs decreased while the serum MI concentration remained unchanged. Urinary excretion of 1,5AG and MI increased significantly after blood glucose concentrations reached 200 to 220 mg/dl. A significant negative correlation was observed between serum 1,5AG and glucose concentrations during hyperglycemia. However, no significant correlation was observed between serum MI and glucose concentrations. In this study, we demonstrated that serum and urine 1,5AG and MI levels were changed by blood glucose concentrations. The serum 1,5AG concentration was decreased by continuous hyperglycemia. However, the serum MI concentration does not reflect hyperglycemia.  相似文献   
49.
In 2007–2008, a canine distemper virus (CDV) epidemic occurred among wild animals in Wakayama Prefecture, Japan, and many mammals, including the wild boar and deer, were infected. In this study, CDV prevalence among wild animals was surveyed before and after the epidemic. At first, an enzyme-linked immunosorbent assay (ELISA) with horseradish peroxidase-conjugated protein A/G was established to detect CDV antibodies in many mammalian species. This established ELISA was available for testing dogs, raccoons and raccoon dogs as well as virus-neutralization test. Next, a serological survey of wild mammalians was conducted, and it was indicated that many wild mammalians, particularly raccoons, were infected with CDV during the epidemic, but few were infected before and after the epidemic. On the other hand, many raccoon dogs died during the epidemic, but CDV remained prevalent in the remaining population, and a small epidemic occurred in raccoon dogs in 2012–2013. These results indicated that the epidemic of 2007–2008 may have been intensified by transmission to raccoons.  相似文献   
50.
温室方位和地理纬度对太阳直射光透过率的影响   总被引:4,自引:1,他引:4  
应用数学模型分析了温室方位、连栋数、季节及地理纬度对太阳直射光透过率的影响。在低纬度地区,上述各要素(除纬度外)对温室直射光透过率的影响效果均显著小于高纬度地区。然而,就东西栋温室而言,其栽培床面上的光照分布在高纬度地区和低纬度地区都表现出不均一性特点。  相似文献   
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