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1.
Masayuki Nakamichi 《Primates; journal of primatology》1984,25(2):192-203
Fourteen female Japanese monkeys of the Arashiyama-B group ranging in age from 11 to 29 years were observed to elucidate the
behavioral characteristics of aging monkeys. A positive significant correlation was found between the occurrences of rest
and age, and a negative significant correlation between the occurrences of auto-grooming and age. Younger female monkeys tended
to be in contact with or in proximity to group members, while older female monkeys tended to spend much more time alone. As
for the grooming interactions, younger female monkeys more often groomed others than did older female monkeys. Also, the former
engaged in grooming more frequently than in being groomed, while the latter spent more time in being groomed than in grooming.
The old female monkeys showed no marked decline in rank, but some of them were surpassed by their adult daughters. 相似文献
2.
3.
J J Beintema J Hofsteenge M Iwama T Morita K Ohgi M Irie R H Sugiyama G L Schieven C A Dekker D G Glitz 《Biochemistry》1988,27(12):4530-4538
The amino acid sequence of a nonsecretory ribonuclease isolated from human urine was determined except for the identity of the residue at position 7. Sequence information indicates that the ribonucleases of human liver and spleen and an eosinophil-derived neurotoxin are identical or very closely related gene products. The sequence is identical at about 30% of the amino acid positions with those of all of the secreted mammalian ribonucleases for which information is available. Identical residues include active-site residues histidine-12, histidine-119, and lysine-41, other residues known to be important for substrate binding and catalytic activity, and all eight half-cystine residues common to these enzymes. Major differences include a deletion of six residues in the (so-called) S-peptide loop, insertions of two, and nine residues, respectively, in three other external loops of the molecule, and an addition of three residues at the amino terminus. The sequence shows the human nonsecretory ribonuclease to belong to the same ribonuclease superfamily as the mammalian secretory ribonucleases, turtle pancreatic ribonuclease, and human angiogenin. Sequence data suggest that a gene duplication occurred in an ancient vertebrate ancestor; one branch led to the nonsecretory ribonuclease, while the other branch led to a second duplication, with one line leading to the secretory ribonucleases (in mammals) and the second line leading to pancreatic ribonuclease in turtle and an angiogenic factor in mammals (human angiogenin). The nonsecretory ribonuclease has five short carbohydrate chains attached via asparagine residues at the surface of the molecule; these chains may have been shortened by exoglycosidase action.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
4.
The cdc6 mutants of Schizosaccharomyces pombe have been classified as being defective in progression through the G2 phase of the cell cycle. We cloned an S. pombe gene that could complement the temperature-sensitive growth of the cdc6-23 mutant. Unexpectedly, the cloned gene was allelic to pol3, which encodes the catalytic subunit of DNA polymerase δ. Integration mapping confirmed that cdc6 and pol3 are identical. The cdc6-23 mutant carries one amino acid substitution in the conserved N3 region of Pol3.
Received: 17 October 1996 / Accepted: 19 November 1996 相似文献
5.
An examination of four species of Cirsium disclosed the presence of two new flavonoids in C. lineare. The structure of one was 5,4′-dihydroxy-6,7,3′-trimethoxyflavone (cirsilineol) 4′-monoglucoside and the other 5,3′,4′-trihydroxy-6,7-dimethoxyflavone (cirsiliol) 4′-monoglucoside. Luteolin 7-glucoside was found in C. suffultum, and pectolinarin and linarin in C. kamtschaticum and C. pectinellum. 相似文献
6.
Resting spore formation during short time-scale upwelling and its significance were investigated in the field and by a simple
theoretical model. Field observations of spore formation ofLeptocylindrus danicus were made off Izu Peninsula, Japan. A rapid increase in ratio of resting spore to vegetative cell numbers indicated thatL. danicus formed resting spores quickly as a response to nutrient depletion in the upwelled water, although only a very low number
of resting spores was found in the upwelling. A simple model was constructed to investigate the possible advantages of spore
formation during short time-scale upwelling. This showed that there is a critical time-scale for resting spore formation to
be advantageous. The nutrient depletion period of the upwelling off Izu was shorter than the critical time-scale determined
by the model. Rapid-sinking of resting spores may increase further the critical time-scale, unless spores return with upwelling
water. For short time-scale upwelling, the vegetative cell may be better suited than the resting spore for enduring a short
period of nutrient depletion.
Contribution from Shimoda Marine Research Center, University of Tsukuba, No. 475. 相似文献
7.
cAMP in Anabaena cylindrica: Rapid Changes in Cellular Levels in Response to Changes in Extracellular Environments 总被引:2,自引:0,他引:2
The cellular level of cyclic 3',5'-AMP (cAMP) in the cyanobacteriumAnabaena cylindrica changed transiently in response to changesin extracellular environments. When the cells were transferedfrom dark to light, or anaerobic to aerobic conditions in thedark, the cAMP level rapidly decreased within one min and thengradually recovered. Addition of carbonyl cyanide m-chlorophenylhydrazone(CCCP) which inhibits ATP synthesis caused an increase in cAMPlevel in the light but not in the dark. The level of cAMP increasedseveral fold by lowering the pH from 8 to 6. On the contrary,a rise of pH from 6 to 8 caused a decrease in the cAMP level.It is suggested that the change in membrane electrochemicalpotential is involved in the regulation of cellular cAMP concentration. (Received January 27, 1989; Accepted June 19, 1989) 相似文献
8.
Primary structure of an N-linked sugar chain derived from glucoamylase of Rhizopus niveus 总被引:2,自引:0,他引:2
K Takegawa N Kawasaki S Iwahara K Yamamoto T Tochikura B Mikami Y Morita 《Biochimica et biophysica acta》1989,990(1):98-100
The primary structure of the N-linked sugar chain of Rhizopus niveus glucoamylase (major component) was investigated. The carbohydrate moiety was released from the polypeptide backbone by Flavobacterium sp. endo-beta-N-acetylglucosaminidase digestion. Studies using the method of exoglycosidase digestion of the fluorescent pyridylamino derivative, gel-permeation chromatography on Bio-Gel P-4 and 400-MHz 1H-NMR spectroscopy revealed that the most abundant structure is (Man)8-GlcNac-ol. 相似文献
9.
Southern hydridization analyses of genomic DNAs from various dnaJ mutants of Escherichia coli showed that mutant K7052, which has well characterized dnaK706 and dnaJ705 double mutantions, is a deletion mutant. The deletion is about 8.0 kb long and encompasses the whole of the dnaKdnaJ operon. 相似文献
10.
Plasmid expression and maintenance during long-term starvation-survival of bacteria in well water. 总被引:9,自引:7,他引:2 下载免费PDF全文
Strains of enteric bacteria and pseudomonads containing plasmid R388::Tnl721 (Tpr, Tcr) or pRO101 (Hgr, Tcr) were starved for over 250 days in sterile well water to evaluate effects of starvation-survival on plasmid expression and maintenance. Viable populations dropped to between approximately 0.1 and 1% of the initial populations. Escherichia coli(pRO101) and Pseudomonas cepacia(pRO101) lost both viability and plasmid expression at a lower rate than strains containing R388::Tnl721. Three patterns of host-plasmid interaction were detected: (i) no apparent loss of plasmid expression, (ii) loss of plasmid expression on initial recovery with subsequent expression upon resuscitation, and (iii) loss of capability to produce functional plasmid resistance. 相似文献