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11.
Growth of chimpanzees reared at the Kumamoto Primates Park of Sanwa Kagaku Kenkyusho Co. Ltd. was studied cross-sectionally from the viewpoints of somatic growth and reproductive maturation. Distance and velocity curves were expressed using spline function method. Males showed adolescent growth acceleration in body weight, with a peak at 7.86 yrs of age, but not in trunk length. Females showed continuous rapid growth from mid-juvenile to adolescent phase in both body weight and trunk length, but no isolated adolescent spurt. The Sanwa chimpanzees matured at about 12.5 yrs of age for females and 15.0 yrs for males. The mean adult weights and trunk lengths were 53.2 kg and 507.8 mm for males and 42.7 kg and 481.6 mm for females. The Sanwa chimpanzees had similar growth patterns to those of the Yerkes chimpanzees, although they showed a slight delay in infancy, and a higher growth rate from the early juvenile phase onwards. Growth patterns in these two laboratories may be regarded as “normative” for laboratory-reared chimpanzees. They matured earlier than wild chimpanzees by more than two years. The major reason for the retarded maturation in wild chimpanzees is the delay of growth from infant to the early juvenile phases (0–4 yrs of age), probably owing to a limited nutritional supply from the mother. Development of the testes comprised three phases: slow growth from infant to juvenile (until 6.4 yrs); rapid growth around adolescence (until 9.2 yrs); and adult (mean testicular volume, 187 cm3). Setting the nutritional standard at 2,000–2,600 Cal/day (= Kcal/day) per adult, calories were considered for captive chimpanzees in each age class.  相似文献   
12.
The density of a Japanese serow (Capricornis crispus) population, which has been in stable habitat conditions and free from hunting and predation, was investigated by direct observation of serows at Kusoudomari (336 ha), Wakinosawa village, Aomori Prefecture, Japan, during 1977–89. The vegetation, composed of mature mixed forest ofThujopsis with deciduous trees (43.2%), secondary forest of deciduous trees (23.4%) and a plantation of coniferous trees (30.0%) showed little change during the study period. The serows were counted 17 times each winter for 14 consecutive years. The serow population maintained a stable density with a mean of 12.5 individuals km−2 (SD=1.4) ranging from 8.6 to 14.6 km−2. The ratio of the proportion of kids (<1 year old) to serows more than 1 year old decreased, but density did not decrease during the study period. Though extremely severe winters with heavy snowfall in 1984–86 caused a decline in serow density, the density recovered within a few years. It was considered that the stability of the serow density resulted mainly from the stable food supply and the lack of human disturbance, such as forest cutting in the habitat. Stable population density for a long period is probably related to the social organization of the serow.  相似文献   
13.
The inhibitory effect of capsaicin on axoplasmic transport in cultured dorsal root ganglion cells was analyzed by video-enhanced contrast microscopy. Capsaicin inhibited particle transports in a dose-dependent manner, irrespective of the diameter of axons. The effect of capsaicin was reversible at low concentrations. Capsaicin affected both the anterograde and retrograde transport. Large organelles were more sensitive to capsaicin than small ones in the retrograde transport. An experiment using calcium-sensitive dye, Fura 2, indicated that capsaicin raised the intraneuronal free calcium concentration preceding the inhibition of the transport. Electron microscopy revealed that microtubules and neurofilaments are disorganized and disoriented by capsaicin. We reached a conclusion that capsaicin inhibits fast axoplasmic transport of both anterograde and retrograde directions in all types of somatosensory neurons in culture by disorganizing intraaxonal cytoskeletal structures, through the elevated intracellular Ca2+ concentration. © 1993 John Wiley & Sons, Inc.  相似文献   
14.
A new technique was devised for the dynamic detection of the axoplasmic transport of β-radioactively labeled materials in which a semiconductor radiation detector was used as the β-ray counter. The detector element is a silicon p-n junction diode and has a diameter of 2.0 mm. With this detector, the β-radioactive distribution of axoplasmic transport could be measured in an axon maintained physiologically without cutting nerves. This method makes possible determination of the transport rate using one bundle of peripheral nerves. The rate in the bullfrog was 6.4 mm per hour at 24.0 °C. Temperature effects on the bullfrog axoplasmic transport were also observed at different temperatures, ranging from 5.0 to 24.0 °C. At these temperatures the rate increased as an exponential function of temperature from 1.1 to 6.4 mm per hour. Within this temperature range, the Q10 is 2.5 and an Arrhenius plot of the natural logarithm of velocity versus the reciprocal of absolute temperature yielded an apparent activation energy of 14.8 Kcal. This technique offers great advantages in permitting direct study of the axoplasmic flow of the axon in a physiological condition.  相似文献   
15.
Peripheral blood leukocytes (PBL) from patients with toxoplasmosis were shown to be highly responsive to in vitro stimulation with Toxoplasma gondii extract as measured by incorporation of [3H]methylated thymidine. Analysis of Toxoplasma-specific proliferative cells in PBL by using monoclonal antibodies specific for human T cell subsets revealed that the Toxoplasma-specific proliferation response of PBL from the patients was mediated by Leu 1, Leu 3a positive cells, that is, helper/inducer T cells. Tests for the Toxoplasma-specific proliferation response may provide a readily available method for the diagnosis of congenital toxoplasmosis, especially during the newborn period.  相似文献   
16.
The crystal structures of (1→3)-α-d-glucan triacetates were studied by X-ray diffraction measurements on fibre diagrams. The oriented films annealed in water at high temperature were of higher crystallinity and occurred as two crystalline polymorphs (GTA I and GTA II) depending on the samples and also the annealing temperature. All reflections in GTA I were indexed with a pseudo-orthorhombic unit cell with a = 1·753, b = 3·018 and c(fibre axis) = 1·205 nm. From the fibre repeat data coupled with the density data and the presence of only the (003) reflection on the meridian, an extended three-fold helical structure was proposed. Although some reflections in GTA II split from the layer lines, the basic unit cell was a monoclinic system with a = 1·685, b = 3·878, c (fibre axis) = 1·210 nm and γ = 112·2°. A similar three-fold structure to GTA I was proposed from the almost identical fibre repeat and the conformational analysis on (1→3)-α-d-glucan. It was concluded that, on acetylation, the d-glucan structure changed from the fully extended two-fold helix to the extended three-fold accompanied by some extent of chain shrinking.  相似文献   
17.
In order to investigate whether a vasa -like protein is present in germ line cells of Xenopus , antibodies were produced which react specifically with synthetic oligopeptides of sequences from near the N- or C-termini or with one including the DEAD box of the Drosophila vasa protein.
Only the antibody against the oligopeptide including the DEAD box reacted strongly with germ plasm (GP) or with cytoplasm of germ line cells of Xenopus embryos by immunofluorescence microscopy. By immunoelectron microscopy, the antibody was demonstrated to react with the GP-specific structure, germinal granules, in cleaving embryos, and with their derivatives in the germ line cells of embryos at stages extending from gastrula to feeding tadpole. It also reacted with mitochondria not only in the GP and the germ line cells but also in somatic cells, and with myofibrils in muscle cells. By Western blotting, the antibody was shown to react with several bands of Mr 42–69 ± 103 in protein samples from Xenopus embryos. In samples from Drosophila ovaries, it reacted with a Mr 71 ± 103 band which was probably the vasa protein. This indicates the possibility that Xenopus embryos contain several DEAD family proteins. One of these is present on germinal granules, resembling the vasa protein on polar granules of Drosophila .  相似文献   
18.
Catharanthine and akuammicine, together with ajmalicine and strictosidine, were isolated from a culture strain of Catharanthus roseus suspension cells. The biosynthetic capability of the cultured cells to produce akuammicine, catharanthine and vindoline was confirmed by feeding experiments with dl-tryptophan-[3-14C] to yield the radioactive alkaloids.  相似文献   
19.
Radioisotopically labelled l-leucine and l-valine were fed to Pisum sativum and incorporated into squalene and β-amyrin. Chemical degradation of the radioactive squalene revealed an equal distribution of the radioactivity in the isopentenyl pyrophosphate(IPP)-derived and the 3,3-dimethylallyl pyrophosphate(DMAPP)-derived moieties of the squalene molecule, unlike the unbalanced distribution in favour of the DMAPP-derived moiety of a monoterpenoid molecule biosynthesized from these amino acids by higher plants.  相似文献   
20.
The immunostimulatory effects of the representative dental resin monomer 2-hydroxyethyl methacrylate (HEMA), a HEMA derivative that does not contain a double bond (2-hydroxyethyl isobutyrate, HEIB), and polymerized water-soluble oligomers of HEMA (PHEMA) were investigated. It is known that expression levels of either or both of CD54 and CD86 in THP-1 cells are increased by exposure to sensitizing substances. In this study, the expression levels of CD54 and CD86, the production of reactive oxygen species (ROS), and the viability of the cells were measured after 24 h of incubation with these materials at different concentrations. The concentrations of the materials that induced the expression of both CD54 and CD86 were low in the following order: NiSO4, HEMA, and methyl methacrylate (MMA). These results indicate that these dental resin monomers have lower sensitizing potentials than NiSO4. Although HEIB, which lacks a double bond, resulted in negligible ROS production and reduced cytotoxicity than HEMA, it induced the expression of CD54 and CD86. Comparison of the results for HEMA and HEIB indicates that dental resin monomer-induced sensitization may be related not only to the oxidative stress related to the methacryloyl group but also to the structures of these compounds. Of particular interest is the result that a water-soluble PHEMA oligomer with a relatively high-molecular weight also exhibited negligible cytotoxicity, whereas the expression level of CD54 increased after exposure to PHEMA at a high concentration. This result serves as a warning that polymerized substances also have the potential to induce sensitization. This study provides insight into the nature of allergic responses to dental resin materials in clinical use and may facilitate the development of more biocompatible restorative materials in the future.  相似文献   
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