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71.
Regular collections of ichthyoplankton were made with a larva net at 9–14 stations from Oct. 1983 to Dec. 1988 in Kagoshima Bay, totalling 817 collections from 66 cruises. A total of 2172 bregmacerotid larvae obtained from 195 collections of 33 cruises were identified asB. atlanticus (2001),B. neonectabanus (169),B. macclellandii (1) andB. nectabanus (1, tentative identification). The peaks of mean densities of larvae collected occurred in autumn forB. atlanticus andB. neonectabanus. The larvae ofB. atlanticus occurred throughout the bay, and their densities and frequency of occurrence were lower in the northern part of the bay. In the southern part of the bay, stations in its southwest quadrant showed higher densities than the others. The larvae ofB. neonectabanus occurred only in the southern part of the bay in which stations in the northwest quadrant showed higher densities than the others.  相似文献   
72.
Two hundreds and fifty eight strains of microorganisms have been isolated from 526 samples (soil, leaf and river water gathered from 17 prefectures) by repeating liquid enrichment culture techniques in the medium containing biphenyl, diphenylmethane, diphenylethane or terphenyl, as the sole source of carbon.

In the course of investigation, several strains were found to produce a large amount of γ-benzoylbutyric acid from biphenyl. Furthermore these strains utilized p-Cl-biphenyl and produced p-Cl-benzoic acid in good yield.

Microorganisms obtained were almost short rod, motile bacteria, and fungi were also found from the screening medium of diphenylethane.  相似文献   
73.
This paper presents a study on the enzyme reduction of the disulfide bond and the following results have been found.

In enzyme preparation, antioxidants showed a stability effect and EDTA appeared to have both enzyme stabilization and solubilization. On the distribution of the enzyme activity in subcellular fractions, the water soluble fraction appeared to contain the major released enzyme activity. The enzyme was inhibited with several metals. Hg2+ and transition metals were the most toxic. The substrate specificity of this enzyme was wide for the low molecular substrates, but the protein disulfide reducing activity was not detected in this preparation. It was assumed that the thiol-disulfide transhydrogenase was coupled with glutathione reductase and the disulfide substrates were reduced by the system involving the two enzymes. A new method for the direct recording of an enzyme-catalyzed thiol-disulfide interchange using diphenyl disulfide and p,p-dinitro diphenyl disulfide was devised.  相似文献   
74.
An index of intensity of sexual selection proposed by Nishida (1992: Res. Popul. Ecol. 34: 373–382) was examined. Two examples were presented to show that Nishida's index was not free from confounding effect of mortality schedule. Importance of removing the phylogenetic effects in comparative analyses was also discussed.  相似文献   
75.
76.
One of the family of voltage-gated calcium channels (VGCC), the N-type Ca2+ channel, is located predominantly in neurons and is associated with a variety of neuronal responses, including neurodegeneration. A precise mechanism for how the N-type Ca2+ channel plays a role in neurodegenerative disease, however, is unknown. In this study, we immunized N-type Ca2+ channel α1B-deficient (α1B−/−) mice and their wild type (WT) littermates with myelin oligodendrocyte glycoprotein 35–55 and analyzed the progression of experimental autoimmune encephalomyelitis (EAE). The neurological symptoms of EAE in the α1B−/− mice were less severe than in the WT mice. In conjunction with these results, sections of the spinal cord (SC) from α1B−/− mice revealed a reduction in both leukocytic infiltration and demyelination compared with WT mice. No differences were observed in the delayed-type hypersensitivity response, spleen cell proliferation, or cytokine production from splenocytes between the two genotypes. On the other hand, Western blot array analysis and RT-PCR revealed that a typical increase in the expression of MCP-1 in the SC showed a good correlation with the infiltration of leukocytes into the SC. Likewise, immunohistochemical analysis showed that the predominant source of MCP-1 was activated microglia. The cytokine-induced production of MCP-1 in primary cultured microglia from WT mice was significantly higher than that from α1B−/− mice and was significantly inhibited by a selective N-type Ca2+ channel antagonist, ω-conotoxin GVIA or a withdrawal of extracellular Ca2+. These results suggest that the N-type Ca2+ channel is involved in the pathogenesis of EAE at least in part by regulating MCP-1 production by microglia.  相似文献   
77.
Neuronal voltage-gated potassium channels, KV7s, are the molecular mediators of the M current and regulate membrane excitability in the central and peripheral neuronal systems. Herein, we report novel small molecule KV7 openers that demonstrate anti-seizure activities in electroshock and pentylenetetrazol-induced seizure models without influencing Rotarod readouts in mice. The anti-seizure activity was determined to be proportional to the unbound concentration in the brain. KV7 channels are also expressed in the bladder smooth muscle (detrusor) and activation of these channels may cause localized undesired effects. Therefore, the impact of individual KV7 isoforms was investigated in human detrusor tissue using a panel of KV7 openers with distinct activity profiles among KV7 isoforms. KCNQ4 and KCNQ5 mRNA were highly expressed in detrusor tissue, yet a compound that has significantly reduced activity on homomeric KV7.4 did not reduce detrusor contraction. This may suggest that the homomeric KV7.4 channel plays a less significant role in bladder contraction and further investigation is needed.  相似文献   
78.
79.
A fungus parasitic on a fern, Dennstaedtia wilfordii (Dennstaedtiaceae), was found at the foothill of Mt. Fuji, Yamanashi Prefecture, Japan. Its hyphae spread within host mesophyll cells and through intercellular spaces, forming coiled haustoria in the epidermal and mesophyll cells. The hyphae emerged either through stomata or by disrupting epidermal cell junctions. The hyphae spreading over the abaxial leaf surface generated one-septate, thin-walled basidia. All the morphological features observed were characteristic of the genus Herpobasidium. The species identification of the fungus as H. filicinum by morphology was supported by molecular phylogenetic analyses of the D1/D2 region of the large subunit rRNA gene.  相似文献   
80.
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