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61.
62.
Haruki Ochi 《Environmental Biology of Fishes》1985,12(2):155-160
Synopsis Reproductive behavior of the temperate damselfish, Chromis notata, was investigated on the island of Mukaishima, Japan, almost daily during the breeding season in 1982. Both males and females
repeated reproductive cycles many times during the breeding season. Females had a strong tendency to spawn a whole clutch
on one nest during a few hours. The average number of eggs which a male gained per reproductive cycle was estimated at 38560
(480–131100 eggs). Males ordinarily cared for eggs until just prior to hatching, but abandoned more than half of the nests
with the eggs numbering less than 11568.
Contribution 207 from the Mukaishima Marine Biological Station. 相似文献
63.
64.
65.
C.D. Hassall A.J. Gandolfi R.C. Duhamel K. Brendel 《Chemico-biological interactions》1984,49(3):283-297
The nephrotoxicity of chlorotrifluoroethylene (CTFE) was examined using isolated rabbit renal tubules suspensions. Exposure of the tubules to CTFE resulted in consumption of CTFE, formation of a glutathione conjugate and inhibition of active organic acid transport. Synthetic cysteine, N-acetylcysteine or glutathione conjugates of CTFE inhibited transport indicating S-conjugation as a possible toxic pathway. 1,2-dichlorovinyl glutathione (DCVG), a model synthetic glutathione conjugate, was used to examine the degradation and toxicity of these conjugates. DCVG inhibited rabbit renal tubule transport in vivo and in vitro. The DCVG was found to be degraded with the evolution of glutamine and glycine to produce the ultimate nephrotoxicant, dichlorovinyl cysteine. Dichlorovinyl cysteine is then bioactivated with the release of ammonia. This sequential degradation explains the latency of DCVG-induced renal transport inhibition relative to dichlorovinyl cysteine. It is now evident that certain halogenated ethylenes are capable of being biotransformed to glutathione conjugates in the kidney with their subsequent hydrolysis to nephrotoxic cysteine conjugates. 相似文献
66.
Bovine Nucleus Caudatus Acetylcholinesterase: Active Site Determination and Investigation of a Dimeric Form Obtained by Selective Proteolysis 总被引:3,自引:3,他引:0
Abstract: The number of catalytic subunits of purified bovine nucleus caudatus acetylcholinesterase (E.C. 3.1.1.7) has been determined by active site labelling with [3 H]diisopropyl fluorophosphate ([3 H]DFP). The 10.5 S, 16 S, and 20 S forms were estimated to contain two, four, and six active sites, respectively, per molecule. A 4.8 S form, which showed a weak amphiphile-dependent activity behavior, was obtained by selective proteolytic digestion with pronase. The inability of the purified 4.8 S form to aggregate after detergent removal, and the molecular mass in the range of 130-165 kD under nondenaturating conditions, indicate that this form is a dimeric form, lacking those hydrophobic regions responsible for aggregation. 相似文献
67.
Specificity and sodium dependence of the active nucleoside transport system in choroid plexus 总被引:5,自引:2,他引:3
The transport of [3H]deoxyuridine by the active nucleoside transport system into the isolated rabbit choroid plexus was measured in vitro under various conditions. Choroid plexuses were incubated in artificial CSF containing 1 microM [3H]deoxyuridine and 1 microM nitrobenzylthioinosine for 5 min under 95% O2-5% CO2 at 37 degrees C and the accumulation of [3H]deoxyuridine measured. Nitrobenzylthioinosine was added to the artificial CSF at a concentration (1 microM) that did not inhibit the active nucleoside transport system but did inhibit the separate, saturable nucleoside efflux system. The active transport of deoxyuridine into the choroid plexus depended on Na+ in the medium, as ouabain, substitution of Li+ and choline for Na+, and poly-L-lysine all inhibited deoxyuridine transport. Thiocyanate in place of chloride and penetrating sulfhydryl reagents also inhibited the active transport of deoxyuridine into choroid plexus. The active transport of deoxyuridine into choroid plexus, which is inhibited by naturally occurring ribo- and deoxyribonucleosides (IC50 = 7-21 microM), was not inhibited (IC50 much greater than 150 microM) by nucleosides with certain alterations on the 2', 3', or 5' positions in D-ribose or 2-deoxy-D-ribose (e.g., adenine arabinoside, 3'-deoxyadenosine, xylosyladenosine); or the pyrimidine or purine rings (e.g., 6-azauridine, xanthosine, 7-methylinosine, or 8-bromoadenosine). Other analogues were effective (IC50 = 8-26 microM; e.g., 5-substituted pyrimidine nucleosides, 7-deazaadenosine, 6-mercaptoguanosine) or less effective (IC50 = 46-145 microM; e.g., 5-azacytidine, 3-deazauridine) inhibitors of deoxyuridine transport into the isolated choroid plexus. 相似文献
68.
Phospholipid-Sensitive Ca2+ -Dependent Protein Kinase Preferentially Phosphorylates Serine-115 of Bovine Myelin Basic Protein 总被引:1,自引:0,他引:1
R. Scott Turner C.-H. Jen Chou† Gonzalo J. Mazzei Philip Dembure ‡ J. F. Kuo 《Journal of neurochemistry》1984,43(5):1257-1264
Phospholipid-sensitive Ca2+ -dependent protein kinase (PL-Ca-PK) and cyclic AMP-dependent protein kinase (A-PK) both preferentially phosphorylated serine residues of bovine myelin basic protein (MBP). Tryptic peptide maps of MBP phosphorylated by PL-Ca-PK or A-PK, however, revealed different phosphopeptides, suggesting a difference in the intramolecular substrate specificity for the two enzymes. Serine-115 of MBP, in the sequence (-Arg-Phe-Ser(115)-Trp-), was found to be a preferred and probably major phosphorylation site for PL-Ca-PK. Because serine-115 of bovine MBP corresponds to serine-113 of rabbit MBP, an in vivo phosphorylation site reported by Martenson et al. (1983), and PL-Ca-PK is present at a very high level in brain and myelin, it is suggested that the enzyme may be responsible for the in vivo phosphorylation of this and other sites in MBP. 相似文献
69.
Structural comparison of the two distinct sugar binding sites in wheat germ agglutinin isolectin II 总被引:12,自引:0,他引:12
C S Wright 《Journal of molecular biology》1984,178(1):91-104
70.
The home range ofTakydromus tachydromoides was studied in a grassland area from April 1977 to November 1978. The mean size of home range did not differ markedly between
sexes; 136.5 m2 for males and 130.8 m2 for females. Home ranges of adults overlapped greatly in each sex, and the lizard was considered to be non-territorial. Individuals
showed return movement to a definite area (sleeping site) within the home range, and the home range did not shift within a
year or between years. Characteristics of the home range of this grassland-inhabiting lizard were discussed in relation to
resource abundance and predation pressure. 相似文献