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1.
Angiogenesis plays an important role in the proliferation and metastasis mechanisms of malignant tumors. Vascular endothelial growth factor (VEGF), a group of cytokines that contribute to angiogenesis and vasculogenesis. This study aimed to investigate the serum VEGF-A concentrations in dogs with various proliferative diseases. A total of 202 dogs that were histopathologically diagnosed with proliferative diseases were included in the study. Serum VEGF-A concentrations were measured using enzyme-linked immunosorbent assay. Median serum VEGF-A concentrations in dogs were as follows: healthy dogs, 4 pg/ml [0–21 pg/ml]; hepatocellular carcinoma, 30 pg/ml [0–158 pg/ml, P=<0.001]; hepatocellular adenoma, 32 pg/ml [0–49 pg/ml, P=0.003]; hepatic nodular hyperplasia, 18 pg/ml [0–51 pg/ml, P=0.595]; adrenal pheochromocytoma, 32 pg/ml [0–187 pg/ml, P=<0.001]; adrenocortical carcinoma, 32 pg/ml [3–161 pg/ml, P=0.002]; adrenocortical adenoma, 27 pg/ml [0–106 pg/ml, P=0.005]; colorectal adenocarcinoma, 36 pg/ml [0–75 pg/ml, P=0.002]; colorectal adenoma, 43 pg/ml [0–48 pg/ml, P=0.144]; inflammatory colorectal polyps, 37 pg/ml [0–111 pg/ml, P=<0.001]; pulmonary adenocarcinoma, 35 pg/ml [4–107 pg/ml, P=0.002]; pulmonary histiocytic sarcoma, 35 pg/ml [0–131 pg/ml, P=0.016]; and follicular thyroid carcinoma, 35 pg/ml [0–106 pg/ml, P=0.009]. The serum VEGF-A concentrations were significantly higher in dogs with neoplastic lesions compared to healthy dogs, except for colorectal adenoma. High serum VEGF-A concentrations were observed in dogs with proliferative diseases. The present study suggests that angiogenesis-inhibiting therapy, which targets VEGF-A, may be useful for canine neoplastic diseases.  相似文献   
2.
In this study, we showed that feeding rats the organic extract of scallop shells (scallop shell extract) caused a decrease in the weights of white adipose tissues in rats fed a high-fat diet. In addition, the cholesterol concentration in the serum of rats that received a diet containing scallop shell extract was significantly lower than that in the serum of rats on the control diet. Feeding this scallop shell extract to rats increased the fecal weight as well as the fecal excretion of bile acids. The amino acid composition of the feces from rats fed the scallop shell extract was different from that of feces from rats fed the control diet, and treatment of the extract with pepsin and pancreatin identified a protein with a molecular weight of 90 kDa (90-kDa protein) as one of the indigestible proteins. Interestingly the 90-kDa protein was found to be identical to a free radical-scavenging protein we previously identified and showed the ability to bind bile acids. These results suggest that indigestible proteins (resistant proteins) in the scallop shell extract, including the 90-kDa protein, inhibit the absorption of bile acid by binding to it and cause increased excretion of fecal bile acid, which subsequently may decrease the serum cholesterol level.  相似文献   
3.
We have previously reported that the scallop shell extract possesses free radical scavenging activity. In this study, we isolated a glycoprotein with a molecular weight of approximately 90 kDa (named 90-kDa protein) which showed 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and superoxide anion radical scavenging, reducing, and ferrous ion-chelating activities. Amino acid composition analysis showed that the 90-kDa protein was rich in Asx (Asp or Asn), Ser and Gly residues. A BLAST search of partial amino acid sequences determined by matrix-assisted laser desorption/ionization tandem time-of-flight mass spectrometry revealed that the 90-kDa protein is a novel protein. The 90-kDa protein is a yellow protein that contains fluorescent substances. To the best of our knowledge, this is the first report of a radical scavenging protein from the scallop shell.  相似文献   
4.
1,2-Diarylpropane-1,3-diol-type lignin model compounds, 1,2-bis(4-hydroxy-3-methoxyphenyl)propane-1,3-diol (1) and 1-(3,4-diethoxyphenyl)-2-(4-methoxyphenyl)propane-1,3-diol (2), were pyrolyzed at 500 degrees C for 4 s to clarify the thermal behavior of beta-1 subunits in lignin. Products were monitored by gas chromatography/mass spectrometry. The cleavage of the Calpha-Cbeta bond to produce benzaldehydes such as 4-hydroxy-3-methoxybenzaldehyde (9) and phenylethanals as the counterparts such as 4-hydroxy-3-methoxyphenylethanal (10) occurred in pyrolyses of both 1 and 2. In pyrolysis of 1, an oxetane pathway leading to the formation of Z/E-stilbenes without the gamma-CH2OH group such as Z/E-4,4'-dihydroxy-3,3'-dimethoxystilbene (3) was predominant. In pyrolysis of 2, the oxetane pathway was minor, while pathways producing a dimer with a =CgammaH2 group by loss of water and a dimer with an alpha-carbonyl group were predominant. Pyrolysis of Japanese cedar wood provided 3 and 10 in approximately 0.8% and 0.6% yields, respectively, based on the Klason lignin content, while pyrolysis of a guaiacyl bulk dehydrogenation polymer gave them in a very small amount.  相似文献   
5.
冰藏鲢的鲜度变化对其鱼糜凝胶作用的影响   总被引:13,自引:0,他引:13  
通过比较不同冰藏时间的鲢所制鱼糜在各种加热温度下的凝胶化和凝胶劣化的特性,考察了鲢的鲜度变化与鱼糜凝胶作用能力的关系。实验结果表明:冰藏0 ̄9天鲢鱼糜,在30℃低温一段加热时凝胶的形成与链鲜度关系不大;85℃一段加热时,凝胶化能力随鲜度下降而降低;30 ̄85℃二段加热与30℃一段加热相比,两者凝胶破断强度之间的差值随鲢鲜度的下降而减小;60℃加热条件下,凝胶劣化程度随原料鲜度下降而明显加剧。据此可见:鲜度对鲢鱼糜凝胶作用能力的影响主要表现在凝胶劣化方面。85℃高温一段加热和30 ̄85℃二段加热的凝胶强度之所以受鲜度下降而影响,都是由于加热时经过了易劣化的60℃温度区所致。从总体上看,鲢肉蛋白质在冰藏条件下较为稳定,保持较强的凝胶化能力。  相似文献   
6.
Age-related changes in bone mineral density (BMD), cross-sectional area and strength strain index (SSI) of the long bones in the limbs and first lumbar vertebra of male Wistar rats were measured by a peripheral quantitative computed tomography (pQCT) method. One hundred and ten rats aged 2-30 months were used. The results indicate that the total (cortical + trabecular), cortical and trabecular BMD values of the metaphysis and cortical BMD values of the diaphysis in the long bones varied for each bone and differed from those of the first lumbar vertebra. The total BMD of long bones showed high values at 6-21 months and then decreased, but these did not always coincide with cortical and trabecular BMD. The values of SSI in the long bones varied. The values of total and cortical BMD and SSI of lumbar vertebra increased for 6-12 months and then decreased, but the trabecular BMD increased after 12 months. The total area in both the long bones and the first lumbar vertebra increased with the decrease in cortical area and the increase in the trabecular area with increasing age. It was concluded that age-related changes in bones, similar to those observed in humans, could be observed in some bones and parameters, although the age in rats when the so-called peak bone mass appears in the whole skeleton could not be clearly determined.  相似文献   
7.
Dogs, cats, and pigs have a bicornuate uterus, and transuterine migration of embryos occurs in 40% or more of pregnant animals. However, the mechanism of the transuterine migration has not been elucidated in dogs. Thus, we investigated the occurrence of transuterine migration of embryos when embryos were retained in an unilateral uterine tube with more ovulated ova (Experiment 1), when one ovary was excised (Experiment 2), and when ova ovulated from the right and left ovaries were fertilized with sperm from male dogs with different blood types (Experiment 3). Transuterine migration of embryos was observed in 7/8 (87.5%), 10/10 (100%), and 11/17 (67.4%) fertilized animals in Experiments 1, 2, and 3, respectively. In Experiment 3, intrauterine embryo mixing reported in pigs did not occur. These findings suggest that transuterine migration of embryos occurs due to the number of embryos that enter the uterus but that differences in the number of ovulated ova between the right and left ovaries or the number of embryos retained in the uterine tube do not affect the migration.  相似文献   
8.
The correlation between the serum hydroxyproline concentration and serum activity levels of TRAP and BALP was examined in 41 cows. The correlated coefficient (r) was 0.6391 for TRAP and 0.3147 for BALP, respectively. Judging from the significant correlation to the serum hydroxyproline concentration, serum TRAP activity is an index for bone metabolism in cows. Serum TRAP activity was therefore measured in 205 healthy cows (2-9 years old) in order to observe the changes in bone resorption with aging and milk production. TRAP levels differed slightly between group A (< or =4 yrs) and B (5 yrs< or =) at the same stage of lactation. The activity levels rose slightly at the height of lactation stage and during the dry stage.  相似文献   
9.
Grain hardness, amylose content, and glutenin subunit composition are critical determinants for end‐use properties of wheat. To improve the end‐use properties of domestic wheats, we studied these traits between the Australian and North American wheat classes exported to Japan in 2009 and 2011 by analyzing the corresponding alleles. Most hard classes had Pina‐D1b or Pinb‐D1b. A partial waxy allele (Wx‐B1b) was found in all Australian Standard White (ASW) seeds in 2009 and two‐thirds of ASW seeds in 2011. All or most American hard wheat seeds had Glu‐D1d. Most U.S. Western White (WW) seeds had a null allele (Glu‐A1c) or alleles that lacked one of the two Glu‐B1 subunits. Most hard red winter (HRW) seeds had Glu‐B3b or Glu‐B3g. Quality characteristics of these classes seemed to be consistent with these results. In addition, we also found new Glu‐1 and Glu‐3 alleles in HRW and WW. These results suggested that although there are variations in its allelic composition from year to year, each class has unique quality‐related alleles corresponding to its end use. We proposed two matrices for classification of starch properties on the basis of Pin and Wx allelic combinations and for classification of gluten strength on the basis of glutenin allelic combinations.  相似文献   
10.
The purpose of this study was to examine: 1) whether caffeine in the fertilization medium under mineral oil is essential for bovine in vitro fertilization by fully capacitated spermatozoa, 2) the minimum concentration of caffeine that shows an adverse effect on the motility of preincubated spermatozoa. Cumulus-oocyte complexes with heterogeneous-appearing ooplasm were matured in in vitro culture for 24 h and used for insemination. The fertilization rates of the preincubated spermatozoa introduced into the fertilization medium containing 0 mM or 5 mM caffeine were examined. The fertilization rate of the spermatozoa introduced into the medium without caffeine (final concentration of caffeine at fertilization was 0.27-0.35 mM) was significantly higher than that in the medium with 5 mM caffeine (82.4% vs 55.2%, P<0.05). When the final concentration of caffeine at fertilization was reduced ten-fold (0.02-0.03 mM), the fertilization rate was not significantly improved (86.0%). The motility of the preincubated spermatozoa introduced into the fertilization medium containing 0-5 mM caffeine was examined. The sperm motility in the fertilization medium without caffeine was significantly higher than that in the fertilization medium with more than 2 mM caffeine. These results indicate that caffeine in the fertilization medium is not essential for bovine in vitro fertilization by fully capacitated spermatozoa, and that more than 2 mM caffeine has an adverse effect on preincubated (capacitated) sperm motility.  相似文献   
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