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991.
Gazza squamiventralis sp. nov. is described as the fifth species of the genus, based on the holotype and eight paratypes, 42–96 mm in standard
length, collected along the east coast of Africa, from Kenya to Mozambique. The species is similar to other congeners in general
appearance, differing clearly from them in having the ventrolateral surface of the body scaled anterior to a line from the
pectoral fin base to the pelvic fin origin (vs naked) and a smooth supraorbital ridge (vs finely serrated). Additionally,
the species differs from G. dentex, G. rhombea, and G. achlamys in having the dorsolateral surface of the body scaled anterior to a vertical through the tip of the posterior branch of the
supratemporal canal (vs corresponding region naked), and from G. minuta in having the first dorsal fin pterygiophore narrowly expanded anteriorly, with a concave margin (vs broadly expanded, with
a convex or linear margin), and a short antrorse extension of the first anal fin pterygiophore (vs long). A key to the five
species of the genus Gazza is provided.
Received: May 30, 2000 / Revised: September 16, 2000 / Accepted: January 16, 2001 相似文献
992.
Polydactylus bifurcus sp. nov. is described on the basis of a single specimen collected from Lombok Island, Indonesia. The new species is distinguished
from all other Indo-Pacific Polydactylus species by the following combination of characters: 15 pectoral fin rays, 5 pectoral filaments, 69 pored lateral line scales,
30 gill rakers, second spine of first dorsal fin very strong and lateral line bifurcated on caudal fin base, extending to
posterior margins of upper and lower caudal fin lobes.
Received: October 19, 2000 / Revised: April 21, 2001 / Accepted: April 25, 2001 相似文献
993.
The full-length sense cDNA for sweet potato granule-bound starch synthase I (GBSSI) driven by the CaMV 35S promoter was introduced into the sweet potato by Agrobacterium tumefaciens-mediated transformation. Out of the 26 transgenic plants obtained, one plant showed the absence of amylose in the tuberous root as determined by the iodine colorimetric method. Electrophoresis analysis failed to detect the GBSSI protein, suggesting that gene silencing of the GBSSI gene occurred in the transgenic sweet potato plant. These results demonstrate that starch composition in the tuberous root of sweet potato can be altered by genetic transformation. 相似文献
994.
Effect of host shoot clipping on carbon and nitrogen sources for arbuscular mycorrhizal fungi 总被引:2,自引:0,他引:2
The effect of clipping of the host-plant shoot on the sources of carbon and nitrogen for the arbuscular mycorrhizal (AM) fungus Gigaspora margarita was determined by measuring 13C in spores and hyphae in cocultures of C3 and C4 plants and by differential 15N labeling. C3 and C4 plants, which have different δ13C values, were grown in the same container separated by a series of hyphal compartments. The C3 and C4 plants were applied with 14N- and 15N-urea, respectively. After clipping of the C3 shoots, spore δ
13C gradually approached that of the C4 roots. Hyphal δ
13C paralleled that of spores. Spore % 15N was similar to that of mineral N in the C4 plant compartment. Thus C in G. margarita coming from the clipped plants decreased with time. This demonstrates that C in AM fungi comes from living plants, whilst
the N in spores comes mostly from the soil.
Accepted: 28 November 2000 相似文献
995.
996.
997.
An improved method is described for the micro determination of acidic glycosaminoglycans after digestion with chondroitinase-ABC and -AC. The determination is based on the color production of D-gluco-4-enepyranosyluronic acid-containing disaccharides produced by the action of chondroitinase-ABC and -AC (acidic glycosaminoglycans-endoeliminase) when the periodate-thiobarbituric acid method is applied to the alpha,beta-unsaturated disaccharides. Suitable conditions for the quantitative assay are described. 相似文献
998.
Y Niho N Kimura Y Yamano Y Yamamoto Y Hirota J Ono R Takaki 《International journal of cell cloning》1985,3(1):22-32
Erythroid-potentiating activity (EPA) was detected in culture medium conditioned by a human cancer cell line (KONT) that produces colony-stimulating activity (CSA), using erythroid colony formation in vitro. EPA in the medium conditioned by the KONT cells (KONT-CM) was markedly heat stable. After treating KONT-CM at 80 degrees C for 30 min, 30% EPA remained, while CSA was completely inactivated. Both EPA and CSA appeared in approximately the same fractions of the gel filtration, indicating a molecular weight of approximately 30,000 daltons. EPA bound partially to Concanavalin-A Sepharose, whereas CSA almost did not bind. Our results indicate that EPA can be separated from CSA based on heat stability and binding to Concanavalin-A Sepharose. 相似文献
999.
Y Wataya H Satake O Hiraoka T Aji K Morishige J Y Kimura A Ishii A Matsuda T Ueda K Fukukawa 《Nucleic acids symposium series》1986,(17):149-151
Carbocyclic inosine is a potent inhibitor for the growth of the promastigote form of Leishmania tropica and Leishmania donovani. In culture, the EC50 values of carbocyclic inosine are 8.3 X 10(-8) and 1.3 X 10(-7) M for the promastigotes of L. tropica and L. donovani, respectively. On the other hand, it is less toxic towards mouse mammary tumor FM3A cells: the EC50 value is 2.7 X 10(-4)M. Carbocyclic inosine is metabolized by Leishmania promastigotes to give carbocyclic adenosine-5'-triphosphate(aristeromycin-5'-triphosphate) and carbocyclic guanosine-5'-triphosphate. This metabolic conversion provides a mechanism for the parasite-selective toxicity of carbocyclic inosine. Carbocyclic inosine was found to be active against L. donovani amastigotes in an in vivo-like cultivation in vitro. 相似文献
1000.
The effect of moxisylyte hydrochloride on isolated human penile corpus cavernosum tissue was investigated and compared with other a-adrenergic antagonists. Moxisylyte produced a concentration-dependent relaxation of a norepinephrine-induced (1 x 10(-5) M) contraction of the corpus cavernosum tissue. Pretreatment with 1 x 10(-6) M doses of moxisylyte reduced competitively the norepinephrine-induced contraction. The competitive effect of prazosin was strongest among four tested agents, followed by phentolamine, moxisylyte, and then yohimbine. The activity ratio for each antagonist is 2.4 for moxisylyte, as compared with 28.2 for prazosin, 6.7 for phentolamine, and 1.6 for yohimbine respectively. Moxisylyte hydrochloride is an agent with potential clinical and research uses capable of producing erection when injected intra-cavernously. 相似文献