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31.
Fructosamine, a glycated serum protein, was evaluated as an index of glycemic control in normal and diabetic cats. Fructosamine was determined manually by use of a modification of an automated method. The within-run precision was 2.4 to 3.2%, and the day-to-day precision was 2.7 to 3.1%. Fructosamine was found to be stable in serum samples stored for 1 week at 4 C and for 2 weeks at -20 C. The reference range for serum fructosamine concentration in 31 clinically normal colony cats was 2.19 to 3.47 mmol/L (mean, 2.83 +/- 0.32 mmol/L). In 27 samples from 16 cats with poorly controlled diabetes mellitus, the range for fructosamine concentration was 3.04 to 8.83 mmol/L (mean, 5.93 +/- 1.35 mmol/L). Fructosamine concentration was directly and highly correlated to blood glucose concentration. Fructosamine concentration also remained high in consort with increased blood glucose concentration in cats with poorly controlled diabetes mellitus over extended periods. It is concluded that measurement of serum fructosamine concentration can be a valuable adjunct to blood glucose monitoring to evaluate glycemic control in diabetic cats. The question of whether fructosamine can replace glucose for monitoring control of diabetes mellitus requires further study.  相似文献   
32.
Adaptations that maximise food intake are dependent on food and/or habitat types. However, there have been few studies on the ability of floodplain primary freshwater fish to rapidly change their morphology, especially the internal one, to maximise utilisation efficiency of food resources in response to environmental fluctuations during their life history. We investigated morphological changes of an Acheilognathinae species (Acheilognathus longipinnis) that inhabits creeks in Japan to determine whether body shape variation correlated with environmental characteristics, including water depth, current velocity, vegetation cover and food availability. When shifting from floodwater-level to low-water-level season, the current velocity of the study area increased as the water level decreased, causing a significant increase in periphyton and a significant decline in zooplankton and phytoplankton. Concurrently, during the short period when A. longipinnis grow from the juvenile to the premature stage, changes in internal morphology, that is intestinal elongation, and changes in external morphology such as an increase of body depth were observed. In contrast, intestinal length significantly decreased in the adult stage. Our findings suggest that morphological changes between floodwater-level and low-water-level seasons associated with juvenile to premature development are an adaptation to changes in food availability due to environmental fluctuations. Additionally, the shortening of the intestine from the premature to the adult stage may be an adaptive strategy for reproduction.  相似文献   
33.
Summary The results of tests of combustion toxicity, hygroscopicity, and adhesive strength for fire retardant-treated plywood are described. The plywood was prepared from veneers treated with diammonium phosphate and ammonium bromide, and from glue mixed with poly (ammonium phosphate). Furthermore, the plywood boards were coated with boric acid. High ammonium phosphate and low or 0 ammonium bromide contents with the boric acid-coatings gave the greatest improvement in the combustion toxicity. Influence of almost all the treatments on the hygroscopicity was not significant. In all treatments the dry adhesive strength and the cyclic boil adhesive strength were slightly and considerably reduced, respectively.  相似文献   
34.
Behavior of lignin in supercritical methanol (250–270°C, 24–27 MPa) was studied by using lignin model compounds at the tin bath temperature of 270°C with a batch-type reaction vessel. Guaiacol and veratrole were selected as a guaiacyl type of aromatic ring in lignin, while 2,6-dimethoxyphenol and 1,2,3-trimethoxybenzene as a syringyl one. In addition, biphenyl and β-O-4 types of dimeric lignin model compounds were, respectively, studied as condensed and ether linkages between C6-C3 phenyl propane units. As a result, both guaiacyl and syringyl types of aromatic rings were very stable, and the biphenyl type was comparatively stable under supercritical conditions of methanol. However, β-ether linkage in the phenolic β-O-4 model compound was cleaved rapidly into guaiacol and coniferyl alcohol, which was further converted to its γ-methyl ether. Non-phenolic β-O-4 model compound was, on the other hand, converted initially into its α-methyl ether and degraded further to produce guaiacol. These lines of evidence imply that in lignin macromolecules, the new phenolic residues are continuously formed and depolymerized repeatedly in supercritical methanol into the lower molecular products, mainly by the cleavage of the dominant β-ether structure in lignin.  相似文献   
35.
Effects of side chain hydroxyl groups on pyrolytic β-ether cleavage of phenolic model dimers were studied with various deoxygenated dimers under pyrolysis conditions of N2/400°C/1 min. Although phenolic dimer with hydroxyl groups at the C α and C γ positions was much more reactive than the corresponding nonphenolic type, deoxygenation at the C γ -position substantially reduced the reactivity up to the level of the nonphenolic type. These results are discussed with the cleavage mechanism via quinone methide intermediate formation, which is activated through intramolecular hydrogen bonds between C α and C γ hydroxyl groups.  相似文献   
36.
A 1344 bp fragment of the 16S ribosomal DNA (rDNA) sequence was used to determine the genetic relationship of Pasteurella pneumotropica isolates from laboratory rodents. A total of 30 nucleotide sequences of P. pneumotropica, including 24 wild strains, 3 reference strains, and 3 nucleotide sequences deposited in GenBank, were examined for heterogeneity of their 16S rDNA sequences. Phylogenetic analysis based on 16S rDNA sequence discriminated 5 types of branching lineages. Of these 5 types, 3 types had significant associations with mice or rats, and 2 had significant associations with the beta-hemolytic phenotype. These results suggest that 16S rDNA sequencing of P. pneumotropica isolates demonstrates genetic heterogeneity and phylogenetic discrimination in terms of their hemolytic phenotype and host associations.  相似文献   
37.
38.
Epigenetic systems play crucial roles in the differentiation of a mammalian fertilized egg into hundreds of cell types exhibiting distinct phenotypes, using a set of DNA molecules comprising about 3 billion nucleotides. Genome-wide analyses of epigenetic marks have revealed the remarkably well-established and well-maintained structure of the epigenome, consisting of DNA methylation and histone modifications that vary their state in a tissue type- and developmental stage-specific manner at numerous genomic loci. DNA methylation profiles comprising numerous tissue-dependent and differentially methylated regions (T-DMRs), found at such loci, are unique to every type of cell and tissue, and illuminate molecular networks that represent their phenotypes. T-DMRs are located in not only genic but also nongenic regions-including transposable genetic elements, such as short interspersed transposable element. Epigenetic studies indicate that the molecules that perform these modifications directly, such as DNA methyltransferases and eukaryotic histone methyltransferases, or indirectly, such as CpG-binding protein and noncoding RNAs-and combinations of these-contribute to the DNA methylation profile. It remains to be addressed how these molecules precisely find their target genomic loci.  相似文献   
39.
Nucleotide sequences of ribosomal internal transcribed spacer (ITS1) and mitochondrial NADH dehydrogenase I (NDI) gene were analyzed to genetically characterize aspermic Fasciola forms in Korea. From the difference in ITS1 sequences, Korean flukes were divided into 3 haplotypes represented by Kor1, Kor2 and Kor1/2, which had nucleotides identical to F. hepatica, F. gigantica and those overlapped between the two species, respectively. NDI sequences also showed that Korean flukes could be classified into 3 distinct haplotypes (Kor1: F. hepatica-type, Kor2a and Kor2b: F. gigantica-type). The sequences of Kor1 and Kor2a were 100% identical to those of the haplotypes Fsp1and Fsp2, respectively, which are major Fasciola forms in Japan. These findings strongly suggest that aspermic Fasciola forms in Korea and Japan originated from same ancestors and have recently spread throughout both countries.  相似文献   
40.
To clarify the role of avian Pasteurella multocida capsule in pathogenesis, adhesion of capsulated strains P-1059, X-73 and Pm-18, and noncapsulated strains P-1059B, Pm-1 and Pm-3 to chicken embryo fibroblast (CEF) cells was compared. Number of adherent organisms of the capsulated strains to CEF cells were approximately three times as much as noncapsulated strains indicating that adhesive properties were enhanced by the presence of bacterial capsule. Pretreatments of the bacterial cells with heat, trypsin, or with antiserum caused a marked decrease in adhesion of capsulated strain P-1059 and its noncapsulated variant P-1059B. However, depolymerization of capsular hyaluronic acid with high dose of hyaluronidase enhanced adhesion of these strains. Combined treatments of the bacterial cells with both hyaluronidase and trypsin significantly (P < 0.05) inhibited the adherence of strain P-1059 as compared to the treatment only with trypsin, but strain P-1059B was not affected. SDS-PAGE profiles of crude capsular extract (CCE) prepared from capsulated strain P-1059 and its noncapsulated variant P-1059B grown on dextrose starch agar (DSA) plates by heating at 56 degrees C in a 2.5% NaCl solution demonstrated eight protein bands of 28, 34, 36, 39, 52, 56, 63 and 93 kDa. The 28, 34 and 36 kDa proteins were commonly major for both strains, and the 39 kDa protein was major only for strain P-1059 but poor in strain P-1059B. Outer membrane protein (OMP) profiles were identical with a major protein at 34 kDa and four minor proteins between the two strains. The adhesion of strain P-1059 and strain P-1059B to CEF cells was inhibited significantly (P < 0.01) by treatment with rabbit antisera against P-1059, P-1059B, CCE or 39 kDa protein of strain P-1059 as compared to the treatment with either PBS or with normal rabbit serum. These results indicated that an antigenic 39 kDa protein in the capsule may be responsible for adhesion of avian P. multocida type A strains to CEF cells as a virulence factor.  相似文献   
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