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1.
Pigments and a UV-absorbing substance in corals and a blue-green alga living in the Great Barrier Reef 总被引:4,自引:0,他引:4
Pigments and UV-absorbing substances in several species of coralsand a blue-green alga harvested in the environs of the GreatBarrier Reef were studied by measuring the in vivo reflectionspectra of intact samples and absorption spectra of their waterextracts with a recording spectrophotometer set on a biologicalresearch vessel. Red, pink, mauve and violet colors of fourspecies of Acropora were thus found to be due to differencesin the relative content of two pigments designated as P(pigment)-560and P-590, according to the maximum wavelength in mµ oftheir major absorption peaks. A yellow species of Acropora anda red species of Pocillopora contained different pigments, P-500and P-480, respectively. All these five species of corals contained,in addition to the above pigments, a UV-absorbing substancehaving an absorption peak near 320 mµ. The contents ofthis substance in the organisms seemed to be very high as judgedfrom its band height relative to band heights of the visiblepigment bands. Blue-green algal cells harvested near the sameenvirons contained a similar UV-absorbing substance in additionto phycobilin pigments. The spectral characteristics of thepigments and the UV-absorbing substance found in the coralsand alga are presented in this paper.
1The present study was carried out in cooperation with Drs.F. T. HAXO, P. HALLDAL and S. W. JEFFREY on the research vessel,R. V. "Alpha Helix", of University of California during the1966 expedition to the Great Barrier Reef, North Queensland,Australia, and was supported by the National Science Foundationof the U. S. A. (Received December 3, 1968; ) 相似文献
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SATOSHI TANAKA HIDEAKI TOJO KYOKO KASAI TORU SAWASAKI CHIKASHI TACHI 《Pigment cell & melanoma research》1994,7(3):152-157
Dominant black-eyed white phenotypes are one of the most commonly observed traits in domestic animals. Their genetic control mechanisms, however, have not been elucidated. As the first step to approach the problem, we examined histologically the patterns of the distribution of pigment cells in Shiba goats (two each of day-73-postcoitum and day-112-postcoitum fetuses, and a 15-week-old kid) with the dominant black-eyed white phenotype. Melanocytes were present and fully pigmented in the choroid and the sclera of eyes, as well as in dorsal skin epidermis of the fetuses and of the kid. Melanocytes were also found in approximately 6% of the hair bulbs in the fetal dorsal skin, while the rest (94%) lacked them. Hair follicles of the kid did not harbor melanocytes except for some in the early anagen stage. The results suggest that the survival of melanocytes was inhibited specifically in the hair follicles of the Shiba goat with the dominant black-eyed white phenotype and that the ostensibly similar phenotypes in the Shiba goat and in the SI or W mutants of the mouse, where melanocytes die en route to the hair bulbs, are regulated by different mechanisms. 相似文献
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NORIYUKI KOIZUMI HIDEAKI TAKAHASHI MITSURU MINEZAWA TAKESHI TAKEMURA SHUJI OKUSHIMA 《Molecular ecology resources》2007,7(2):240-242
We isolated and characterized 14 polymorphic microsatellite loci for the field gudgeon, Gnathopogon elongatus elongatus, a popular freshwater species in streams including agricultural canals in Japan. The number of observed alleles for each locus ranged from 9 to 24, and the values of observed and expected heterozygosities ranged from 0.750 to 1.000 and from 0.832 to 0.953, respectively. These microsatellite markers will be useful for studies of population genetic structure and genetic variability of the field gudgeon. 相似文献
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1. Twenty usual amino acids examined were shown to be dividedinto two groups with respect to their actions on the flowerformation (A) and frond multiplication (B) in a long-day duckweed,L. gibba G3. Amino acids of the first group (e.g., arginine)inhibited A without preventing B, and those of the second group(e.g., lysine) inhibited both A and B. The inhibition of flowerformation was always the greatest when amino acid was appliedat the induction period. 2. The floral inhibition by arginine applied at the inductionperiod was partially or wholly reversed by the simultaneousaddition of other amino acid (especially lysine) or by one additionallong day. The inhibitions by lysine, however, were not reversedby arginine. 3. It was discussed that the terminal step(s) of photoperiodicinduction process might depend largely on the relative in vivoconcentrations of amino acids. (Received January 28, 1964; ) 相似文献
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The absorption spectra of suspensions of living micro-organisms 总被引:18,自引:0,他引:18
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The pigments contained in the inner seed coats of Cucurbitapepo, C. maxima and C. moschata were investigated spectroscopicallyusing both intact tissues and their ether extracts. The pigment(s) contained in C. pepo and C. maxima was inferred to be "protochlorophyll"and/or Mg vinyl pheoporphyrin a5 which are indistinguishablefrom each other by mere spectroscopic observations. The coatsof C. moschata were found to contain Mg-free vinyl pheoporphyrina5 which has so far been reported to exist only in some Chlorellamutants. The spectra of these pigments in intact tissues wereremarkably different from those of the ether extracts, indicatingthe profound difference in their physical states in vitro andin vivo. It was discussed that the "protochlorophyll b" reportedearlier by SEYBOLD and EGLE might have been vinyl pheoporphyrina1. (Received July 14, 1960; ) 相似文献
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LIDA XING PHIL R. BELL PHILIP J. CURRIE MASATERU SHIBATA KUOWEI TSENG ZHIMING DONG 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2012,45(4):500-506
Xing, L, Bell, P.R., Currie, P.J., Shibata, M., Tseng, K. & Dong, Z. 2012: A sauropod rib with an embedded theropod tooth: direct evidence for feeding behaviour in the Jehol group, China. Lethaia, Vol. 45, pp. 500–506. A fragmentary rib from the Lower Cretaceous (Barremian) Yixian Formation in northeastern China preserves rare, direct evidence of feeding behaviour by an unidentified theropod. The rib, which comes from the holotype of Dongbetitan, preserves an embedded, broken theropod tooth. Comparison of the tooth with all known theropods from the Yixian Formation suggests that it belongs to a new taxon of medium‐sized theropod. Given the large size difference between the sauropod and the theropod and the absence of reactive bone growth around the tooth, the bite likely occurred post‐mortem during scavenging. Recognition of a new, medium‐sized theropod increases the known diversity of taxa from the Yixian Formation and helps fill a gap in the theropod palaeoecology of that formation, which previously consisted of only small (<2 m) forms. □China, Cretaceous, feeding behaviour, theropod, titanosauriformes, sauropod. 相似文献