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71.
BCG- or glucan-elicited murine peripheral macrophages released a cytotoxin in the presence of loach egg lectin, whereas proteose peptone-, glycogen-, or thioglycollate-elicited or resident macrophages did not. The macrophages that released cytotoxin coincided with those that showed lectin-dependent macrophage-mediated cytolysis (LDMC) in response to loach egg lectin. The cytotoxin released by BCG-elicited macrophages in response to loach egg lectin had a molecular weight of 55 K daltons. The macrophages that released cytotoxin and other cytotoxic macrophages such as those that showed LDMC- and antibody-dependent macrophage-mediated cytolysis (ADMC) were examined by using several antibodies to surface antigens of macrophages. The results showed that murine peripheral macrophages could be divided into three types. Resident macrophages (Type I) which had common macrophage antigens (Mac-1 and B12) showed only LDMC in response to wheat germ agglutinin. Some elicited macrophages (Type II) were asialo GM1-positive and showed both ADMC and LDMC in response to wheat germ agglutinin. Activated macrophages (Type III) showed LDMC in response to loach egg lectin and cytotoxin-release, but had no antigen detectable with monoclonal anti-macrophage antibody (C14). These three types of macrophages were clearly distinguished diagrammatically by their roof-shaped, rocket-shaped and irregular-shaped profiles of activities and antigens. These data suggest that several selected surface antigens of macrophages are associated with distinct cytotoxic stages of peripheral macrophages.  相似文献   
72.
Cycling of soil carbon in the first year after a clear-felling was compared with that before the felling in a Japanese red pine forest in Hiroshima Prefecture, west Japan. The daily mean temperature at the soil surface in summer was increased after the felling in comparison to that before felling, and the water content of both the A0 layer and the surface mineral soil was decreased due to the loss of the forest canopy. The rate of weight loss of the A0 layer was reduced after felling. However, accumulation of the A0 layer rapidly decreased because of the lack of litter supply to the forest floor. Low soil respiration after felling was mainly caused by the cessation of root respiration. Analysis of annual soil carbon cycling was then conducted using a compartment model. The relative decomposition rate of the A0 layer decreased whereas that of humus and dead roots in mineral soil increased to some extent after felling. The accumulation of carbon in mineral soil, however, increased slightly due to the supply of humus from roots killed by the felling.  相似文献   
73.
Five species including two new species,Araucarioxylon kiiense Ogura,Taxodioxylon albertense (Penhal.) Shimakura,Cupressinoxylon cryptomerioides Stopes,Xenoxylon watarianum sp. nov. andCedroxylon shimakurae sp. nov., were described from the Upper Cretaceous (Late Turonian-Santonian) of southern Saghalien. Consecutive number from the previous paper (Nishida and Nishida, 1985). Contributions from the Laboratory of Phylogenetic Botany, Chiba University No. 100. Supported by a Grant-in-Aid for Scientific Research from the Ministry of Education, Science and Culture No. 59540441.  相似文献   
74.
Krafft points of diacylglycerophosphocholines (PC) were measured in alkanes-cyclohexane solutions by differential scanning calorimetry, and it was found that they were regularly increased following the increase in alkane content in the solutions and the chain length of the alkanes. From these results it was deduced that the mixing of PC with alkanes occurred in the gel state of the PC, but not in micelles at higher temperatures above the Krafft points. where micellar solutions are provided. The penetration of alkanes into gel state PC was found to be dominated by Langmuir type interaction, and the affinity of alkanes increases with increasing in chain lengths. Above the Krafft points, the micelle formation was confirmed by using the fluorescence probe technique.  相似文献   
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  1. In order to get the knowledge on the age composition of “isaza” population in Lake Biwa and the effect of population density on growth, monthly distribution of mean body length and mean body weight has been analyzed on the basis of monthly haul by “isazabiki” trawl during 1949 to 1953 and also 1960 to 1965.
  2. There is no apparent sex difference in the growth in the first and second years of life.
  3. “Isaza” population is composed of two age groups, age 0 and 1 groups (1+fish), the latter occupying by far the greater part in commercial catch.
  4. During the growth season fishes of both ages feed mainly on zooplankton, though in winter frequently take chironomid larvae, gammaridae and others in volume.
  5. The growth season falls in the period from April to October in both age groups.
  6. A considerable yearly variation occurring in growth is in close connection with the fluctuation of population density of all ages.
  7. The influence affected by the density of age 1 group is larger than that by age 0 group.
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79.
Glomerular vasculature was investigated in the carpCyprinus carpio, the scorpionfishSebastiscus marmoratus, and the marine catfishPlotosus lineatus with the resin-replica method. An afferent arteriole was connected with a glomerulus in every fish. It was slender in the carp, whereas the scorpionfish and marine catfish possessed thick afferent arterioles. The glomerular capillaries were sinusoidal. The divergences, convergences, and windings of these capillaries were not well developed in any of the fish. The glomerular capillaries converged into an efferent arteriole in the carp and scorpionfish. In the marine catfish, on the other hand, most of the glomeruli had two efferent arterioles.  相似文献   
80.
Reaction difference of oxyradical generation and luminol-dependent photoemission of zymosan- and phorbol ester-treated neutrophils were investigated using a conventional photomultiplier and ultrasensitive photonic imaging technique. Zymosan-treated cells released a concentrated photonic burst corresponding to the cellular distribution. In contrast, phorbol ester-treated cells produced a negligible level of photoemission, and the additional application of Ca2+ ionophore enhanced the photonic burst, which was gradually spread out into extracellular space. Serine protease inhibitors did not attenuate PMA-induced chemiluminescence but did attenuate zymosan-induced chemiluminescence. This suggests the involvement of serine protease in the respiratory burst of phagocytizing neutrophils.  相似文献   
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