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31.
Ichthyological Research - A taxonomic review of the Sebastes vulpes complex (S. vulpes, S. zonatus and S. ijimae) established the existence of two valid species, Sebastes vulpes Döderlein in... 相似文献
32.
Characterization of Japanese flounder karyotype by chromosome bandings and fluorescence in situ hybridization with DNA markers 总被引:4,自引:0,他引:4
The chromosomes of Japanese flounder, Paralichthys olivaceus, were examined by conventional differential staining methods including G-, Q-, C-, silver (Ag)-, fluorochrome, and replication
R-bandings and by fluorescence in situ hybridization (FISH) with 5S and 18S rDNAs and telomeric DNA as probes. Replication
R-banding substantially made it possible to identify 24 homologous pairs by their RBG-banding pattern and relative length.
Both rDNA loci were mapped to chromosome 1, where 5S and 18S rDNA loci were located at the centromeric region and secondary
constriction, respectively. C-banding revealed that both rDNA loci were heterochromatic, and 18S rDNA loci were positive for
chromomycin A3 but negative for 4′,6-diamidino-2-phenylindole (DAPI) staining. Telomeric FISH signals were observed at all chromosome ends
and at the interstitial region of some chromosomes. The observed results were discussed in relation to the karyotype evolution
in the order Pleuronectiformes. 相似文献
33.
Yutaka Tokiwa Masaru Kitagawa Hong Fan Tetsuji Yokochi Takao Raku Yoichi Hiraguri Shigeo Shibatani Yoshihiko Maekawa Naoki Kashimura Ryuichiro Kurane 《Biotechnology Techniques》1999,13(8):563-566
The transesterification of divinyladipate with adenosine in DMF containing 20% (v/v) DMSO was catalyzed by Streptomyces sp. alkaline protease and esterification occurred exclusively at the 3-position of hydroxyl group of ribofuranose in adenosine to give 3-O-vinyladipoyl adenosine without other products. 相似文献
34.
Otsuki T Nagakura S Wang J Bloom M Grompe M Liu JM 《Journal of cellular physiology》1999,179(1):79-86
Fanconi anemia (FA) is a genetic syndrome predisposing to hematopoietic failure. Little is known about the pathophysiology of FA, except that tumor necrosis factor-alpha (TNF-alpha) is overexpressed in patients. FA group C (Fac) gene knockout mice have been developed in order to model the human disease, but the mice do not spontaneously exhibit aplasia. To investigate secondary influences on hematopoiesis in the Fac-null mice, we studied the sensitivity of hematopoietic progenitor cells (HPC) to death receptor triggering by TNF-alpha and Fas receptor (CD95) ligation. Previously we had found that overexpression of a human FAC transgene protects hematopoietic progenitors from Fas-mediated apoptosis (Wang et al., 1998, Cancer Res 58:3538-3541). In the present experiments with Fac-null mice, growth of erythroid burst-forming units (BFU-E) was significantly inhibited by TNF-alpha and CD95 ligation. Flow cytometric analysis revealed that CD95 was induced more readily in the Fac-null CD34+ cell fraction. Apoptosis induced by TNF-alpha alone or with CD95 ligation also occurred more frequently in null mouse HPC. We then bred null mice against transgenic mice overexpressing TNF-alpha (at serum levels in the range of 100 pg/ml). Resultant Fac-null mice that overexpressed TNF-alpha not only yielded decreased numbers of BFU-E but also expressed higher levels of CD95 in the CD34+ fraction. We conclude that mutation in the Fac protein induces heightened sensitivity to TNF-alpha and Fas receptor ligation, results that may explain the mechanism of anemia in FA-C patients. 相似文献
35.
36.
Sun L Tamaki H Ishimaru T Teruya T Ohta Y Katsuyama N Chinen I 《Bioscience, biotechnology, and biochemistry》2004,68(12):2613-2615
Seven-week old female rats fed restricted foods including the fish oils Docosahesaenoic Acid (DHA) and Eicosapentaenoic Acid (EPA) and perilla oil with food intake decreased by 50%, had increases of fracture force and bone mineral density (BMD) and decreases in levels of Deoxypiridinoline (Dpd) and Calcium (Ca) in the urine, compared with those of rats with osteoporosis due to restricted soy bean oil food intake. Therefore, the fish oils DHA and EPA and perilla oil depressed excretion of urinary Ca and inhibited osteoporosis due to restricted food intake. 相似文献
37.
Tamaki H Sun L Ohta Y Katsuyama N Ishimaru T Chinen I 《Bioscience, biotechnology, and biochemistry》2004,68(7):1578-1580
Running at 0.7 km/h for 10 min every day inhibited development of osteoporosis caused by protein deficient (PD) food intake. Urine alkaline phosphatase (ALP), a marker of bone formation osteoporosis, was not elevated in rats fed PD, when the osteoporosis was inhibited by running. Estrogen supplementation increased bone-breaking energy (BBE), but did not increase bone mineral density (BMD), and did not decrease urinary ALP levels. 相似文献
38.
39.
Esaki H Noda K Otsuki N Kojima A Asai T Tamura Y Takahashi T 《Journal of microbiological methods》2004,58(1):131-134
A total of 63 isolates were screened for the gyrA mutation (87Asp-Tyr) in Salmonella enterica serovars using real time PCR. All of the isolates were successfully identified as resistant or susceptible, consistent with the MIC result of the agar dilution method and gyrA sequencing. 相似文献
40.
Watanabe S Nagashio Y Asaumi H Nomiyama Y Taguchi M Tashiro M Kihara Y Nakamura H Otsuki M 《American journal of physiology. Gastrointestinal and liver physiology》2004,287(6):G1175-G1181
Pancreatic stellate cells (PSCs) play a central role in development of pancreatic fibrosis. In chronic pancreatitis, pancreatic tissue pressure is higher than that of the normal pancreas. We here evaluate the effects of pressure on the activation of rat PSCs. PSCs were isolated from the pancreas of Wistar rat using collagenase digestion and centrifugation with Nycodenz gradient. Pressure was applied to cultured rat PSCs by adding compressed helium gas into the pressure-loading apparatus to raise the internal pressure. Cell proliferation rate was assessed by 5-bromo-2'-deoxyuridine (BrdU) incorporation. MAPK protein levels and alpha-smooth muscle actin (alpha-SMA) expression were evaluated by Western blot analysis. Concentration of activated transforming growth factor-beta1 (TGF-beta1) secreted from PSCs into culture medium was determined by ELISA. Collagen type I mRNA expression and collagen secretion were assessed by quantitative PCR and Sirius red dye binding assay, respectively. Application of pressure significantly increased BrdU incorporation and alpha-SMA expression. In addition, pressure rapidly increased the phosphorylation of p44/42 and p38 MAPK. Treatment of PSCs with an MEK inhibitor and p38 MAPK inhibitor suppressed pressure-induced cell proliferation and alpha-SMA expression, respectively. Moreover, pressure significantly promoted activated TGF-beta1 secretion, collagen type I mRNA expression, and collagen secretion. Our results demonstrate that pressure itself activates rat PSCs and suggest that increased pancreatic tissue pressure may accelerate the development of pancreatic fibrosis in chronic pancreatitis. 相似文献