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81.
Effects of Cytochrome c on Liver Functions of Old Rats   总被引:1,自引:0,他引:1  
WE have shown1,2 that cytochrome c, when orally administered, is absorbed intestinally. The effects of parenterally administered cytochrome c on the liver have been studied by Drabkin3 and Murano4. We have also studied the effects of orally administered cytochrome c on experimental liver injury5.  相似文献   
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83.
Two species of the snakefly genus Mongoloraphidia Aspöck & Aspöck, 1968 from Japan and Taiwan are described as new to science: Mongoloraphidia (Japanoraphidia) occidentalis sp. nov. and Mongoloraphidia (Formosoraphidia) curvata sp. nov. A key to the species of Mongoloraphidia from Eastern Asia is provided. Phylogenetic and biogeographical aspects on the Raphidiidae from Eastern Asia are discussed.  相似文献   
84.
85.
An anastomosing network of extracellular fibrils on the inner surface of the ectoderm layer of amphibian gastrulae has been shown to provide an adequate substratum for attachment and migration by the mesodermal cells. These fibrils contain fibronectin as shown by immunostaining at the light and electron microscope levels. Now we report the presence of laminin, another cell adhesion glycoprotein, as a fibrillar network on the inner surface of the ectoderm layer in gastrulae of the Japanese newt ( Cynops pyrrhogaster ), but its absence on the blastula ectoderm layer, by the immunofluorescent staining using an antiserum specific for mouse laminin. The same antiserum was shown to stain basement membranes of adult newt organs as expected.  相似文献   
86.
SUMMARY 1. Prey selection by the dobsonfly larva, Protohermes grandis (Thunberg), was studied in stony riffles of the Yataro River, central Japan. The density, size distribution and taxonomic composition of available prey were assessed for 2 years. In order to know the encounter rate between prey and this ambush predator, prey mobility was also estimated from patterns of colonization of experimentally detiuded stones.
2. Foregut analyses revealed that maximum size of prey eaten increased with larval size, and large larvae did not take the smallest prey in spite of high availability in all seasons.
3. Charnov's (1976) optimal diet model quantitatively predicted such size-selective feeding under seasonally fluctuating conditions of water temperature and prey availability. Larvae maximized the feeding rate by selecting prey.
4. Maximum width of prey eaten coincided approximately with larval mandible length. Mandible size seemed to play an important role in the selection of prey in the optimal size range.  相似文献   
87.
Exceptionally high levels of intraspecific variation of mitochondrial DNA (mtDNA) sequences encoding 16S ribosomal RNA (16SrRNA) were detected in populations of the land snail Euhadra peliomphala from the eastern part of Japan. Geographical isolation has occurred within small areas and has created many genetically distinct local populations. These are morphologically segregated into two groups: the first consists of populations from the southern part of the Izu Peninsula, and the second of populations from other areas within the peninsula. They are separated by mountains in the middle of the peninsula. Sequence divergences between these two groups were 7.6–9.5%. The sequence divergences and geological ages of the Izu peninsula and its mountains suggest that the divergence rate of mitochondrial 16SrRNA sequences of this species is extremely rapid, approximately 10% per million years. This rapid evolutional")' rate of mtDNA and vicariance events due to tectonic events and sea level changes has also contributed to creating exceptional geographical variation in the mtDNA of this species.  相似文献   
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89.
A comprehensive biogeochemistry model, DNDC, was revised to simulate crop growth and soil processes more explicitly and improve its ability to estimate methane (CH4) emission from rice paddy fields under a wide range of climatic and agronomic conditions. The revised model simulates rice growth by tracking photosynthesis, respiration, C allocation, tillering, and release of organic C and O2 from roots. For anaerobic soil processes, it quantifies the production of electron donors [H2 and dissolved organic carbon (DOC)] by decomposition and rice root exudation, and simulates CH4 production and other reductive reactions based on the availability of electron donors and acceptors (NO3?, Mn4+, Fe3+, and SO42?). Methane emission through rice is simulated by a diffusion routine based on the conductance of tillers and the CH4 concentration in soil water. The revised DNDC was tested against observations at three rice paddy sites in Japan and China with varying rice residue management and fertilization, and produced estimates consistent with observations for the variation in CH4 emission as a function of residue management. It also successfully predicted the negative effect of (NH4)2SO4 on CH4 emission, which the current model missed. Predicted CH4 emission was highly sensitive to the content of reducible soil Fe3+, which is the dominant electron acceptor in anaerobic soils. The revised DNDC generally gave acceptable predictions of seasonal CH4 emission, but not of daily CH4 fluxes, suggesting the model's immaturity in describing soil heterogeneity or rice cultivar‐specific characteristics of CH4 transport. It also overestimated CH4 emission at one site in a year with low temperatures, suggesting uncertainty in root biomass estimates due to the model's failure to consider the temperature dependence of leaf area development. Nevertheless, the revised DNDC explicitly reflects the effects of soil electron donors and acceptors, and can be used to quantitatively estimate CH4 emissions from rice fields under a range of conditions.  相似文献   
90.
The projected increase of atmospheric CO2 concentration ([CO2]) is expected to increase rice yield, but little is known of the effects of [CO2] at low temperature, which is the major constraint to growing rice in cool climates. We grew rice under two levels of [CO2] (ambient and elevated by 200 μmol mol?1) and two nitrogen (N) fertilization regimes in northern Japan in 2003 (cool weather) and 2004 (warm weather) in the field in a free‐air CO2 enrichment (FACE) system. Elevated [CO2] significantly increased grain yield in both years in both N regimes, but the magnitude of the increase differed between years: 6% in 2003 vs. 17% in 2004, with a significant interaction between [CO2] and year. This difference resulted from responses of spikelet number and ripening percentage to elevated [CO2]. Enhancement of dry matter production and N uptake at heading by elevated [CO2] was smaller in 2003 than in 2004, although at maturity there was no difference between years. No significant interaction between N regime and [CO2] was detected in yield and yield components. The results suggest that yield gain due to elevated [CO2] can be reduced by low temperature.  相似文献   
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