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81.
Histiocytic sarcoma (HS) is a rare neoplasm of macrophages or dendritic cells with a poor prognosis in dogs. As the apoptosis inhibitor of macrophage (AIM) is characteristically expressed in canine macrophages, we hypothesised that AIM is involved in the development or progression of HS in dogs. In this study, AIM expression in the tumour region and serum AIM levels in dogs with HS was assessed. Additionally, the effects of AIM overexpression on HS cell viability were investigated using a HS cell line that was selected from five validated HS cell lines. Immunohistochemistry showed that AIM expression was observed in the cytoplasm of the HS cells. CD36, a candidate AIM receptor, was also observed on the cell membrane of HS cells. When the serum AIM level was detected in 36 dogs with HS and 10 healthy dogs via western blot analysis, the AIM levels in the HS dogs were significantly higher than those in the controls. AIM mRNA expression in the 5 HS cell lines varied but was higher than that in the other tumour-derived lines. Among the five HS cell lines, DH82 originally had lower AIM and the highest CD36 expression. When AIM was overexpressed in DH82, therein cell growth speed and invasion, apoptosis inhibition and phagocytic activity were strongly upregulated. These data suggest that elevated intra-tumour expression of AIM could induce the progression of HS cells in dogs. Moreover, elevated serum AIM levels in dogs with HS could serve as a biomarker of HS.  相似文献   
82.
To elucidate the formation and chemical structures of water-soluble material in acid-soluble lignin (ASL), lignin aromatic nuclei model compounds of creosol (I) and 5-methoxycreosol (II) were reacted with xylose or xylan in the presence of apocynol as a counterpart for condensation in 72% sulfuric acid (SA). The reaction of I gave mainly condensation product. However, the condensation reaction of II with apocynol was suppressed because of steric hindrance from the methoxyl group, and II yielded a C-xyloside after refluxing in 3% SA together with condensation products. To obtain information on CHCl3-soluble material in ASL, model compounds of arylglycerol--aryl ethers with guaiacyl (VIII) and syringyl (X) nuclei were treated by the Klason procedure. VIII gave only insoluble polymerized product, while X gave insoluble polymerized product and CHCl3-soluble low molecular weight products, which were dissolved in 3% SA. These results prove earlier views that water-soluble material in ASL consists of condensation products formed from syringyl lignin and monosaccharide units in hemicellulose. In addition, the CHCl3-soluble material in ASL appears to be composed of low molecular weight degradation products from SA treatment of Klason lignin with the syringyl nucleus.Part of this report was presented at the 51st Annual Meeting of the Japan Wood Research Society, Tokyo, April 2001 and at the 47th Lignin Symposium, Fukuoka, October 2002, and was reviewed in Mokuzai Gakkaishi (2002) 48:55–62  相似文献   
83.
The relationship between the recovery of canopy trees after fire and root collar sprout dynamics was investigated during 1998–2000 in a secondary cool-temperate broad-leaved forest consisting of Quercus mongolica var. grosseserrata and Betula platyphylla var. japonica trees, in northern Hokkaido, Japan, which burned in April 1998. All of the Betula trees that were severely damaged, two-thirds of those slightly damaged, and half of those intact in 1998, died within three growing seasons after the fire. By contrast, half of the Quercus trees that were slightly damaged and half of those severely damaged recovered their foliage, and no slightly damaged or intact trees died during the three growing seasons after the fire. Many Betula trees developed several fruiting bodies of wood-destroying fungi on their stems, irrespective of damage severity. Fungi also infected some of the surviving Quercus, although the crowns tended to recover. Although many sprouting Betula were observed in 1998, the number of sprouts declined rapidly over the study period. Multiple regression analyses showed that the survival and growth of Betula sprouts were positively influenced by the number of sprouts in 1998, damage severity in 1998, and the degree of recover or decline during the study period, and were negatively influenced by parent tree size. On the other hand, a few sprouts of Quercus remained alive. Quercus remained dominant and the dominance of Betula was rapidly reduced after the fire. However, many Betula sprouts remained alive. Stand structure will change drastically for the time being.  相似文献   
84.
To utilize acid hydrolysis lignin effectively, chemical conversion to anion-exchange resin was investigated by two methods. Sulfuric acid lignin (SAL) was selected as a typical acid hydrolysis lignin in this experiment. Because it is less reactive, SAL was phenolated with sulfuric acid catalyst to yield reactive phenolized SAL (P-SAL) with p-hydroxyphenyl nuclei. One method was the restricted resinification of P-SAL followed by the Mannich reaction with formaldehyde and dimethylamine to yield a weakly basic anion-exchange resin with an ion-exchange capacity of 2.4mEq/g. Another method was to react resinified P-SAL with glycidyltrimethylammonium chloride to yield a strongly basic anion-exchange resin with an ion-exchange capacity of 2.0mEq/g. The reaction of a simple P-SAL model compound with an epoxide suggested that the phenolic hydroxyl group of the p-hydroxyphenyl nucleus had slightly higher reactivity than that of the guaiacyl nucleus.Part of this report was presented at the 47th Lignin Symposium, Fukuoka, October 2002  相似文献   
85.
Genetically modified corn Bt11 is insect-resistant and expresses Cry1Ab toxin, an insecticidal protein, in kernels. Although Bt11 corn is considered safe based on animal performance, there are no reports available on the clinico-biochemical effects of feeding it to cattle. In this study, we evaluated the effects of feeding Bt11 to calves, using blood and ruminal clinico-biochemical parameters. Our three-month-long feeding experiment demonstrated that calves (n=6), fed with a ration containing 43.3% of Bt11 corn kernels as dry matter, did not develop any discernible clinical, hematological, biochemical, or ruminal abnormalities as compared with control calves (n=6) fed non-Bt11 corn. The results suggest that the transgenic Bt11 has no negative clinico-biochemical effects on calves.  相似文献   
86.
Estrus synchronization requires multiple treatments of hormonal drugs, requiring considerable time and cost. The aim of the present study was to develop an estrus synchronization protocol using intravaginal administration of estradiol benzoate (EB) capsules in goats. Two types of capsules were prepared: an EB capsule that melted immediately after administration and a sustained-release (SR) EB capsule that dissolved slowly and reached a peak after 24 h. Goats with functional corpus lutea were intramuscularly treated with prostaglandin F (PG). At 24 h after PG administration, goats were administered 1 mg of EB solution intramuscularly (PG + 24IM; n = 6) or 1 mg of EB capsule intravaginally (PG + 24EB; n = 6). The SR EB capsule was administered intravaginally at the time of PG administration (PG + SR; n = 6). The control group (n = 6) received only PG. All groups showed estrus within 72 h after PG administration. The onset of estrus did not differ significantly between the PG + 24IM and PG + SR groups but was earlier than in the control group. Estradiol concentration in the PG + SR group peaked at 11.5 ± 6.1 h after EB and PG administration. Peak estradiol concentrations were not significantly different between the PG + 24IM and PG + SR groups (78.0 ± 25.8 and 64.0 ± 38.1 pg/ml, respectively), and were higher than the PG + 24EB and control groups (27.3 ± 8.8 and 14.6 ± 6.1 pg/ml, respectively). These results suggest that intravaginal administration of an EB capsule with a sustained-drug release base is applicable for estrus synchronization, as an alternative to intramuscular administration.  相似文献   
87.
Ten lactating cows were used to determine the effect of feeding non-fibrous carbohydrate (NFC) supplement before grazing on feed intake and nitrogen (N) utilization throughout a grazing season. The experiment was conducted from June to September. Cows grazed twice a day (2.5 h × 2) under a set stocking system and were fed NFC supplement (1 kg/4 kg of milk yield) 2 h before grazing (PRE) or immediately after grazing (POST). Cows were also fed a grass and corn silage mixture ad libitum. Herbage dry matter intake (DMI) was greater for PRE than for POST throughout the experiment and decreased from June to September. Conversely, silage DMI was less for PRE than for POST throughout the experiment and increased over the grazing season. Consequently, total DMI for PRE did not differ from that for POST. Milk urea-N concentration and urinary urea-N excretion in June did not differ between the treatments, whereas that after July was higher for PRE than for POST. Proportion of urinary N excretion to absorbed N intake in June was lower for PRE than for POST, but that after July was higher for PRE than for POST. Feeding NFC supplement before grazing would improve N utilization when cows eat large amounts of herbage high in N.  相似文献   
88.
Morphological variation of the skull was examined in the northern treeshrew (Tupaia belangeri) from various localities across Southeast Asia. Through a multivariate analysis, the treeshrews from South Vietnam exhibited distinct morphological characteristics compared to other populations from Thailand and Laos, and Malaysia. The plots of the specimens of North Vietnam are not randomly mixed with Thailand plots segregation in the scatteregrams of canonical discriminant analysis. Since the skulls of the population from North Vietnam were morphologically similar to those form central Laos and northern and northeastern Thailand, the zoogeographical barrier effect of Mekong River was not clearly confirmed. The population of the Kanchanaburi in western Thailand is clearly smaller in size compared to the other populations. The southern border of the distribution of this species is determined by the Isthmus of Kra or Kangar-Pattani Line. In the northern treeshrew, which is distributed from southern China to Bangladesh and southern Thailand, we have detected osteometrical geographical variation driven by geography. These results indicate that the skull morphology in the Tupaia glis-belangeri complex distinctively differs in South Vietnam, western Thailand, and southern Thailand. The zoogeographical barrier and factor separating these districts are expected to clarify in the future.  相似文献   
89.
Cloning,expression, and tissue distribution of bovine interleukin-21   总被引:3,自引:0,他引:3  
Bovine interleukin-21 (IL-21) cDNA was cloned and sequenced from bovine peripheral blood lymphocytes (PBLs) stimulated with 10 microg/ml concanavalin A (ConA), 10 microg/ml phytohemagglutinin (PHA), and 50 ng/ml phorbol 12-myristate 13-acetate (PMA) for 48 h. The open reading frame of the bovine IL-21 cDNA is 459 bp in length and encodes 152 amino acids. The predicted amino acid sequence is 78.2 and 58.5% homologous to the human and murine IL-21 amino acid sequences, respectively. Recombinant bovine IL-21 was expressed by a baculovirus expression system. The bovine IL-21 was processed to the mature form in insect cells and secreted to the supernatant confirmed by N-terminal amino acid sequencing. The recombinant bovine mature IL-21 induced the proliferation of human IL-2-dependent cells, ILT-MAT. The mRNA expression for bovine IL-21 was observed in the spleen, but not in the brain, heart, lung, liver, and kidney. The bovine IL-21 identified in this study may provide new methods for the enhancement of innate immunity in cows.  相似文献   
90.
Cytotoxic T-lymphocyte (CTL) responses to hemagglutinin (H) protein of canine distemper virus (CDV) were evaluated in dogs using the replication-deficient adenovirus protein expression system. Skin fibroblasts were isolated from two dogs and were infected with recombinant adenovirus bearing the CDV-H gene (Ade-CDVH). CTL assay was performed using fibroblasts expressing CDV-H protein as target cells and peripheral blood lymphocytes (PBL) collected from the same dogs one week after immunization of CDV as effector cells. Specific cytotoxic activity was observed against autologous but not heterologous fibroblasts expressing CDV-H protein. These results indicate that the CTL epitope(s) were localized in the H protein.  相似文献   
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