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71.
A ten-year summary of reproductive parameters for ring-tailed lemurs at berenty, madagascar 总被引:2,自引:2,他引:0
Naoki Koyama Masayuki Nakamichi Ryo Oda Naomi Miyamoto Shinichiro Ichino Yukio Takahata 《Primates; journal of primatology》2001,42(1):1-14
From 1989 to 1998, 204 live births were recorded for ring-tailed lemurs (Lemur catta) at Berenty, Madagascar. Excluding unknown birth dates, the peak month of birth was September, with 82.0% (146/178) occurring
during this period. The offspring sex ratio (1∶1.19) was not significantly different from 1∶1, and there was no association
with the mother's age. The first births occurred at the ages of 2 to 4 yr. The annual birth rate was very low at the age of
2 yr (11.1%), but increased thereafter: to 50.0% at the age of 3 yr, and to 75–85% at the age of 4 or more years. Multiple
births were very rare, since only three sets of twins and one set of triplets were recorded. As for the interbirth interval,
a one-year interval was the most common (92.2%). Infant mortality within the first year was 37.7% (77/204). Neonatal mortality
within the first month accounted for 31.2% of all infant dealths. 相似文献
72.
Masayuki Nakamichi April Silldorff Peggy Sexton 《Primates; journal of primatology》2001,42(3):245-252
The present report describes behavioral reactions of a 33-month-old female infant gorilla to maternal separation in a captive
social group whose composition is similar to that of wild groups. The infant gorilla responded differently to two types of
maternal separation. When she remained alone for a few hours, she cried repeatedly and moved restlessly, indicating protest.
Upon reunion and also for a few days thereafter, an intensification of the mother-infant relationship occurred. On the other
hand, when she was separated from her mother but remained with the other group members for nine days, she did not display
any behaviors that could be characterized as protest, but rather showed clear behavioral depression. During the 9-day separation
period, she hardly played with other group members but she developed affiliative relationships with the leading male. After
the reunion from the 9-day separation, she spent as much time near her mother as before separation and played with other infants
at a level similar to that before separation, while she sometimes displayed behavioral patterns demanding the maintenance
of physical contact with her mother. The present findings are compared with other reports in great apes and human children. 相似文献
73.
Leptocephalus larvae of Gymnothorax minor collected from eastern Kyushu were identified by observation of metamorphosis procedure. The leptocephali were characterized
by 135–142 total myomeres (31–42 predorsal, 87–95 preanal) and the last vertical blood vessel between myomeres 77–85. Diagnostic
pigments were apparent on the head, the somatic (below intestine) and splanchnic (along pronephric ducts) regions, before
the dorsal fin origin, ventrally on the spinal cord, and along the dorsal and anal fin bases. Such pigments were suitable
for species identification of metamorphosing larvae because of their persistence during that process. 相似文献
74.
Seiji Sugimoto Yoshiharu Yokoo Noritaka Hatakeyama Akira Yotsuji Sadao Teshiba Hiroshi Hagino 《Biotechnology letters》1991,13(6):385-388
Summary Higher culture pH of 7.6 was shown to be preferable for the inclusion body formation of salmon growth hormone (SGH) inEscherichia
coli harboring a recombinant plasmid. High-level formation of SGH inclusion bodies was achieved at 33°C (pH 7.6). Growth inhibition by soluble SGH was also observed. 相似文献
75.
Social Relationships Among Ring-Tailed Lemurs (Lemur catta) in Two Free-Ranging Troops at Berenty Reserve, Madagascar 总被引:2,自引:0,他引:2
We observed two free-ranging troops of ring-tailed lemurs at the Berenty Reserve, Madagascar. Kinship affinities in these troops are known only for mothers and their offspring 4 years of age. We attempted to quantify social relationships. Almost all agonistic interactions were dyadic, and triadic agonistic interactions, such as alliances, were very rare. Dominance hierarchies in both sexes in the two troops were not linear. As in cercopithecine monkeys, mothers were dominant over their adult daughters. However, the daughters were not ranked immediately below their mothers. Close proximity and social grooming occurred more frequently between closely related females, such as mother–daughter and sister–sister dyads, than between unrelated females. Frequent-proximity relations also occurred between adult males that had emigrated from another troop and entered the present troop together, even though they did not rank closely to one another. Subordinates were likely to groom and to greet dominants more frequently than vice versa. During group encounters, particular females were involved in agonistic interactions with animals of other troops, regardless of dominance rank. Adult males, regardless of their dominance rank, but not adult females, constantly tried to drive solitary males away. 相似文献
76.
77.
Torimoto N Ishii I Hata M Kobayashi Y Nakamura H Ariyoshi N Kitada M 《Biochimica et biophysica acta》2007,1774(2):223-232
CYP3A4 has unusual kinetic characteristics because it has a large active site. CYP3A4 produced more 4-hydroxytriazolam than alpha-hydroxytriazolam at concentrations of more than 60 muM triazolam, and different steroids had different inhibitory effects on the system. To clarify these interesting observations, the interactions between substrate and substrate/steroid were investigated by theoretical calculations. When two triazolam molecules were docked into the active site, the distance between the O-atom and the 4-hydroxylated site was less than the distance to the alpha-hydroxylated site because of interaction between the two triazolam molecules. Estradiol inhibited both alpha- and 4-hydroxytriazolam formation by 50%. Dehydroepiandrosterone (DHEA) inhibited alpha-hydroxylation more than 4-hydroxytriazolam formation, whereas aldosterone had no effect. When one triazolam molecule and one steroid molecule were simultaneously docked, estradiol increased the distance between the O-atom and the two hydroxylated sites, DHEA only increased the distance between the O-atom and alpha-hydroxylated site, and aldosterone did not change the distances. The relevant angles of Fe-O-C in the hydroxylated site of triazolam also widened, together with increased distance. These findings indicate that formation of a substrate and substrate/effector complex in the active site may be a factor for determining the enzyme kinetic parameters of CYP3A4. 相似文献
78.
Terasaki N Yamamoto N Tamada K Hattori M Hiraga T Tohri A Sato I Iwai M Iwai M Taguchi S Enami I Inoue Y Yamanoi Y Yonezawa T Mizuno K Murata M Nishihara H Yoneyama S Minakata M Ohmori T Sakai M Fujii M 《Biochimica et biophysica acta》2007,1767(6):653-659
We report on the first successful output of electrons directly from photosystem I (PSI) of thermophilic cyanobacteria to the gate of a field-effect transistor (FET) by bypassing electron flow via a newly designed molecular wire, i.e., artificial vitamin K(1), and a gold nanoparticle; in short, this newly manufactured photosensor employs a bio-functional unit as the core of the device. Photo-electrons generated by the irradiation of molecular complexes composed of reconstituted PSI on the gate were found to control the FET. This PSI-bio-photosensor can be used to interpret gradation in images. This PSI-FET system is moreover sufficiently stable for use exceeding a period of 1 year. 相似文献
79.
Photoisomerization mechanism of rhodopsin and 9-cis-rhodopsin revealed by x-ray crystallography
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The primary photochemical process of the visual function has been investigated using the three crystallographic models, 11-cis-rhodopsin, all-trans-bathorhodopsin, and the artificial isomeric 9-cis-rhodopsin. Detailed examination of the atomic displacements and dihedral angle changes of the retinal chromophore involved in the interconversion among these isomers suggests the mechanism of isomerization efficiency. 相似文献
80.
Shun'ichi Kuroda Noritaka Nakagawa Chiharu Tokunaga Kenji Tatematsu Katsuyuki Tanizawa 《The Journal of cell biology》1999,144(3):403-411
By the yeast two-hybrid screening of a rat brain cDNA library with the regulatory domain of protein kinase C ζ (PKCζ) as a bait, we have cloned a gene coding for a novel PKCζ-interacting protein homologous to the Caenorhabditis elegans UNC-76 protein involved in axonal outgrowth and fasciculation. The protein designated FEZ1 (fasciculation and elongation protein zeta-1) consisting of 393 amino acid residues shows a high Asp/Glu content and contains several regions predicted to form amphipathic helices. Northern blot analysis has revealed that FEZ1 mRNA is abundantly expressed in adult rat brain and throughout the developmental stages of mouse embryo. By the yeast two-hybrid assay with various deletion mutants of PKC, FEZ1 was shown to interact with the NH2-terminal variable region (V1) of PKCζ and weakly with that of PKCε. In the COS-7 cells coexpressing FEZ1 and PKCζ, FEZ1 was present mainly in the plasma membrane, associating with PKCζ and being phosphorylated. These results indicate that FEZ1 is a novel substrate of PKCζ. When the constitutively active mutant of PKCζ was used, FEZ1 was found in the cytoplasm of COS-7 cells. Upon treatment of the cells with a PKC inhibitor, staurosporin, FEZ1 was translocated from the cytoplasm to the plasma membrane, suggesting that the cytoplasmic translocation of FEZ1 is directly regulated by the PKCζ activity. Although expression of FEZ1 alone had no effect on PC12 cells, coexpression of FEZ1 and constitutively active PKCζ stimulated the neuronal differentiation of PC12 cells. Combined with the recent finding that a human FEZ1 protein is able to complement the function of UNC-76 necessary for normal axonal bundling and elongation within axon bundles in the nematode, these results suggest that FEZ1 plays a crucial role in the axon guidance machinery in mammals by interacting with PKCζ. 相似文献