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451.
DIVING BEHAVIOR AND PERFORMANCE OF HARBOR PORPOISES, PHOCOENA PHOCOENA, IN FUNKA BAY, HOKKAIDO, JAPAN 总被引:1,自引:0,他引:1
Seiji Otani Yasuhiko Naito Akito Kawamura Masahiro Kawasaki Shigetoshi Nishiwaki Akiko Kato 《Marine Mammal Science》1998,14(2):209-220
In order to monitor the diving behavior of free-ranging cetaceans, microdataloggers, with pre-programmed release mechanisms, were attached to the dorsal fins of two female harbor porpoises ( Phocoena phocoena ) in Funka Bay, Hokkaido, Japan, in 1994. The two loggers were successfully recovered and a total of 141 h of diving data (depth and water temperature in 4,671 dives) was obtained. Both porpoises dived almost continuously, rarely exhibiting long-term rest at the surface. Maximum dive depths were 98.6 m and 70.8 m, respectively, with more than 70% of diving time at 20 m or less. Most shallow dives were V-shaped with no bottom time. The V-shaped dives were significantly shallower in dive depth and shorter in dive duration than U-shaped dives. Descent rate was not constant during a dive. The deeper the dive depths, the faster the mean descent and initial descent rates. This suggests that porpoises have anticipated the depth to which they will dive before initiating the dive itself. 相似文献
452.
Ryosuke Fukada Jin Kawano Tomoki Tsuruta Takuto Nonaka Kosuke Sato Susumu Miyajima Shinnosuke Ishigami Takahiro Ishii Keisuke Nishikawa Yoshinori Asakawa Takashi Kamada 《化学与生物多样性》2023,20(4):e202300131
Two new eremophilane-type sesquiterpenoids, fusumaols A ( 1 ) and B ( 2 ), were isolated from the stem-leafy liverwort, Bazzania japonica collected in Mori-Machi, Shizuoka, Japan. Their structures were established using extensive spectroscopic (IR, MS, and 2D NMR) data, and the absolute configuration of 1 was determined by the modified Mosher's method. This is the first time eremophilanes have been discovered in the liverwort genus Bazzania. Compounds 1 and 2 were evaluated for their repellent activity against the adult population of the rice weevil Sitophilus zeamais using the modified filter paper impregnation method. Both sesquiterpenoids showed moderate repellent activities. 相似文献
453.
Hisataka Awata Fumio Endo Akito Tanoue Akito Kitano Yoshikuni Nakano Ichiro Matsuda 《生物化学与生物物理学报:疾病的分子基础》1994,1226(2):168-172
Fumarylacetoacetate hydrolase (FAH) is a metabolic enzyme functioning at the last steo of tyrosine catabolism. Deficiency in this enzyme activity is associated with tyrosinemia type I, characterized by hypertyrosinemia, liver dysfunction, renal tubular dysfunction, liver cirrhosis, and hepatic tumors. We isolated from a human gene library a chromosomal gene related to FAH. The human FAH gene is 30 kilobases long and is split into 14 exons. All of the splice donor and acceptor sites conform to the GT/AG rule. We also analyzed findings in a patient with tyrosinemia type I with respect to the mutation responsible for detects in the enzyme. A nucleotide change from T to G was found in the exon 2 of the gene and this change was accompanied by an amino acid substitution (Phe62Cys). Transfection and expression analysis of the cDNA is cultured BMT-10 cells with the nucleotide substitution demonstrated that the substitution was indeed responsible for the decreased activity of the enzyme in the patient. These results confirmed that the T to G mutation was one of the causes of tyrosinemia type I. Structure of the FAH gene and tests for expression of the mutant FAH will facilitate further understanding of various aspects of FAH. 相似文献
454.
T Sakata E Nakamura Y Tsuruta M Tamaki H Teraoka H Tojo T Ono M Okamoto 《Biochimica et biophysica acta》1989,1007(1):124-126
The content of mRNA for a pancreatic-type phospholipase A2 present in rat gastric mucosa was much greater than that in pancreas. In lung the mRNA for this pancreatic-type phospholipase A2 was also detected, but less than in pancreas. Nucleotide sequence analysis showed that these pancreatic-type phospholipase A2 cDNAs derived from rat gastric mucosa and lung were completely identical to that from rat pancreas (Ohara et al. (1986) J. Biochem. 99, 733-739). This demonstrates that the pancreatic-type phospholipase A2 present in gastric mucosa and lung does not originate from pancreas. 相似文献
455.
Chlorotetracycline has been used in human polymorphonuclear leukocytes as a probe to investigate the state of membrane-bound calcium. We examined the effect of adenosine on the fluorescence responses of CTC-loaded PMNs stimulated with the synthetic chemotactic peptide, formyl-methionyl-leucyl- phenylalanine. Adenosine inhibited the decrease in CTC fluorescence in a dose-dependent fashion and its effect was reversed by theophylline, an adenosine receptor antagonist. Removal of extracellular adenosine by incubating PMNs with adenosine deaminase abolished the effect of adenosine. These data suggest that adenosine inhibits the release of membrane-bound calcium in PMNs that normally occurs in response to chemotactic stimuli, acting via PMN surface adenosine receptors. 相似文献
456.
Kimura K Igarashi Y Kajita A Wang ZX Tsuruta H Amemiya Y Kihara H 《Biophysical chemistry》1990,38(1-2):23-32
A solution X-ray scattering study has been performed on Limulus polyphemus (horseshoe crab) hemocyanin and its dissociated fragments at various pH values in the presence and absence of Ca2+. The scattering patterns of native hemocyanin (48-mer), the half molecule (24-mer), quarter molecule (12-mer) and monomer fraction were measured. The radii of gyration for the four molecular species were calculated from the Guinier plots to be 110.7, 91.3, 77.3, and 36.5 A, respectively. Models which yield good fits to the experimental data are presented. The models were constructed using eight, four and two spheres with a radius of 58 A, assuming the sphere to be the submultiple composed of six subunits. The radii of gyration were calculated on the basis of the model and the values found to be 106, 94 and 73 A, respectively, in good agreement with the experimental results. 相似文献
457.
S Tsuruta K Nakata N Ohata Y Gondo Y Sato T Nakayama K Nakao M Shima N Ishii T Koji 《Biochemical and biophysical research communications》1992,183(3):1147-1152
The effects of tumor necrosis factor-alpha (TNF-alpha) on DNA synthesis in AH66 rat hepatoma cells and rat hepatocytes were analysed by means of [3H]thymidine incorporation. DNA synthesis in AH66 cells was suppressed when AH66 cells were directly incubated with TNF-alpha. When primary culture of rat Kupffer cells was incubated with hepatocyte conditioned media pretreated with TNF-alpha (0-200 U/ml), and AH66 cells were then treated with these hepatocyte/Kupffer cell-conditioned media, TNF-alpha used in the pretreatment caused a dose-dependent increase in DNA synthesis in AH66 cells with a maximum effect amounting to a more than 10-fold increase. In contrast, DNA synthesis in primary culture of rat hepatocytes was not stimulated by the TNF-alpha-pretreated hepatocyte/Kupffer cell conditioned media. These results suggest that TNF-alpha-mediated hepatocyte-Kupffer cell interaction selectively promotes proliferation of rat hepatoma cells. 相似文献
458.
T Imamura H Ohtsuka M Matsushita J Tsuruta H Okada T Kambara 《Biochemical and biophysical research communications》1992,185(2):505-509
The guinea pig complement factor H(FH) and the plasma precursor(PMCFS-1) of the major monocyte-chemotactic factor(MCFS-1) found in the skin site of delayed hypersensitivity reaction(DHR) induced in the guinea pigs were compared in the antigenicity and the function. Both anti-FH-IgG and anti-MCFS-1-IgG formed a single precipitation line against FH, PMCFS-1, MCFS-1 and guinea pig plasma, and these lines fused one another without any spur formation. The inhibition activity of FH for C3bBb was absorbed by anti-MCFS-1-F(ab')2 in a dose-dependent manner. PMCFS-1 inhibited C3bBb activity dose-dependently as FH. These results show that FH is identical to PMCFS-1 and imply that FH, converted to MCFS-1 plays as a monocyte-chemotactic factor in the site of DHR. 相似文献
459.
Iwanami K Matsumoto I Tanaka Y Inoue A Goto D Ito S Tsutsumi A Sumida T 《Arthritis research & therapy》2008,10(6):R130
Introduction
Arthritis induced by immunisation with glucose-6-phosphate isomerase (GPI) in DBA/1 mice was proven to be T helper (Th) 17 dependent. We undertook this study to identify GPI-specific T cell epitopes in DBA/1 mice (H-2q) and investigate the mechanisms of arthritis generation. 相似文献460.
Akito Kazama Akinobu Wada Hiroshi Sakiyama Md. Jamil Hossain Yuzo Nishida 《Inorganica chimica acta》2008,361(9-10):2918-2922
Two dinuclear metal complexes, [Co2(bhmp)(MeCO2)2]ClO4 · 2H2O (1) and [Ni2(bhmp)(MeCO2)2]ClO4 · 2H2O (2), were synthesized with a dinucleating ligand, 2,6-bis[bis(2-hydroxyethyl)aminomethyl]-4-methylphenol [H(bhmp)]. Both complexes were easily soluble in water as well as in DMF. Electronic spectra for both complexes were measured in both solvents and analyzed using the angular overlap model (AOM). From the electronic spectra and molar conductance, both complexes were determined to exist as [M2(bhmp)(MeCO2)2]+ (M = CoII or NiII) in DMF, dissociating perchlorate ions. On the other hand, in water, it was concluded that the acetate ions were partially dissociated and each complex existed as a mixture of some dissociated species, such as [M2(bhmp)(MeCO2)(H2O)2]2+ and [M2(bhmp)(H2O)4]3+ (M = CoII or NiII). Such dissociation was also confirmed by precipitation of the dissociated species when NaBPh4 was added into an aqueous solution of the nickel complex. 相似文献