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排序方式: 共有480条查询结果,搜索用时 15 毫秒
1.
Manabu Fukuda Kohji Takahashi Chiharu Ohkawa Yuya Sasaki Yasushi Hasegawa 《Fisheries Science》2013,79(6):1017-1025
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
2.
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
3.
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
4.
Morita T Shimada A Ohama E Umemura T Fukuda S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1999,61(2):107-111
We performed a pathologic examination of the brains of three dogs in an epileptic beagle colony. Histologically, all the cases had diffuse astrocytosis in the cerebral cortex and basal ganglia as well as the hippocampus, whereas they showed acute nerve cell change in the hippocampus and some other areas of the cerebrum. One of these animals showed laminar myelin pallor associated with the presence of many vacuoles in the IV to VI layers of the bilateral motor cortices. Most of the vacuoles contained fine granules stained with luxol-fast-blue stain. Ultrastructural examination revealed that some oligodendrocytes and perineuronal satellite oligodendrocytes in the bilateral cerebral motor cortices of the two affected dogs had many vacuoles surrounded by myelin-like lamellar structures. These findings suggest a possibility that astrocytosis in the cerebrum and vacuolar degeneration of oligodendrocytes in the cerebral motor cortex may be, at least in part, related to the occurrence or development of seizures. 相似文献
5.
Claro N. Mingala Satoru KonnaiRyoyo Ikebuchi Kazuhiko Ohashi 《Comparative immunology, microbiology and infectious diseases》2011,34(1):55-63
Characterization of CTLA-4, PD-1 and PDL-1 genes from swamp and riverine type water buffaloes was done by molecular cloning, sequencing and phylogenetic analysis. The cloned cDNA of CTLA-4, PD-1 and PDL-1 contained an open reading frame of 666, 849 and 870 nucleotides, encoding a polypeptide of 221, 282 and 298 amino acids, respectively. Nucleotide sequence homology of both CTLA-4 and PDL-1 had 99.8% in swamp and riverine type, which gives the identical polypeptide. Meanwhile, PD-1 genes of swamp and riverine type water buffaloes had 99.2% of homology in nucleotide sequence, which has substitution of two amino acid residues. The hexapeptide motif, phosphatidylinositol 3′-kinase and potential glycosylation sites were conserved within the tribe Bovinae. Phylogenetic analysis confirmed the degree of relationship between the bubaline species and justify the distinctness of each breeds by the bootstrap value generated. 相似文献
6.
Isolation and culture of rabbit primordial germ cells 总被引:2,自引:0,他引:2
Kakegawa R Teramura T Takehara T Anzai M Mitani T Matsumoto K Saeki K Sagawa N Fukuda K Hosoi Y 《The Journal of reproduction and development》2008,54(5):352-357
Primordial germ cells (PGCs) are embryonic precursors of the gametes of adult animals and are considered stem cells of the germline. Since their proliferation in vitro correlates well with the schedule of developmental changes in vivo, they might be interesting research tools for genomic imprinting, germ-cell tumors and fertility. Furthermore, once primordial germ cells are separated and placed on a feeder layer with cytokines, they become cultured pluripotent cell lines called embryonic germ (EG) cells. EG cells share several important characteristics with embryonic stem (ES) cells as they can also contribute to the germ line of chimeras. To investigate the characteristics of PGCs and establish rabbit EG (rEG) cells, we cultured rabbit PGCs (rPGCs) in vitro with various combinations of leukemia inhibitory factor (LIF), basic fibroblast growth factor (bFGF) and forskolin on inactivated mouse embryonic fibroblast (MEF) feeder layers. The present study found PGC proliferation in early cultures and induction of rEG-like colonies. These cells expressed pluripotent markers, such as alkaline phosphatase activity, OCT-4, Sox-2 and SSEA-1, in the undifferentiated state; however, the cells did not develop into a teratoma when injected into the kidney capsules of SCID mice, although the restricted differentiation potentials to neural cells were determined via embryoid body formation. From these characteristics and further characterization of the germ stem cell markers Vasa, SCP-1 and SCP-3, we suggested that these were hybrid cells with characteristics somewhere between PGC and EG cells. 相似文献
7.
Antigenic differences between H5N1 human influenza viruses isolated in 1997 and 2003 总被引:5,自引:0,他引:5
Horimoto T Fukuda N Iwatsuki-Horimoto K Guan Y Lim W Peiris M Sugii S Odagiri T Tashiro M Kawaoka Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(3):303-305
To assess whether the antigenic properties of H5 hemagglutinin (HA) change over time due to antigenic drift, we produced a panel of monoclonal antibodies (mAbs) against the HA of the index H5N1 human influenza A virus, A/Hong Kong/156/97. By immunizing mice with a plasmid expressing this HA and boosting the initial immunization with cell lysates transfected with the plasmid, a total of six hybridomas producing HA-specific mAbs were established: four to the HA1 subunit with hemadsorption-inhibiting activity and two to the HA2 subunit. None of the mAbs to HA1 could bind to the HA of a recent human isolate, A/Hong Kong/213/2003, indicating that there are substantial antigenic differences between the H5N1 human influenza virus isolated in 1997 and that isolated in 2003. 相似文献
8.
9.
Katamoto H Yamada Y Nishizaki S Hashimoto T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2003,65(9):1001-1002
The influence of the season on serum vitamin A, E and beta-carotene concentrations was studied in Japanese Black breeding cattle. Blood samples were collected from 13 cows once a month for a year to determine the serum vitamin concentrations. Mean serum concentrations (+/- SE) of retinol, alpha-tocopherol and beta-carotene were 21.3 +/- 0.5 microg/dl (range 9.9 to 44.9), 215.9 +/- 8.0 microg/dl (range 59.7 to 551.6) and 67.3 +/- 5.1 microg/dl (range 10.6 to 425.2), respectively. All these concentrations were lower than the recommended levels. Serum retinol and alpha-tocopherol concentrations in summer were lower than those in winter. These results suggest that the vitamin A, E and beta-carotene status of Japanese Black breeding cows is inadequate, and feeding high quality forages or dietary vitamin supplementation during summer should be recommended. 相似文献
10.
The activities of the enzymes involved in the malate-aspartate shuttle were measured in peripheral leucocytes of dogs with type 1 diabetes mellitus. In the diabetic dogs, fasting plasma glucose concentrations were twofold greater than control levels despite insulin injections and the activities of malate dehydrogenase (MDH), which plays a crucial role in the malate-aspartate shuttle, were decreased remarkably. The cytosolic ratio of MDH/lactate dehydrogenase (LDH) activity (M/L ratio) in leucocytes of the diabetic dogs was significantly lower than that of normal control dogs. The decrease of the M/L ratio appeared to reflect depression of energy metabolism in leucocytes of the diabetic dogs. The M/L ratio may be a useful parameter to evaluate metabolic conditions in diabetic dogs. 相似文献