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排序方式: 共有3912条查询结果,搜索用时 312 毫秒
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Kuriyama Akira; Takeuchi Masayuki; Kawai Fumio; Kanamori Masao 《Plant & cell physiology》1992,33(5):647-650
The formation of sporophytic shoots, which is induced by treatmentwith benzylaminopurine of gametophyte tissue of Equisetum arvense,can be divided into initiation and developmental phases. Thenitrogen in MS medium was suitable for two phases as well as gametophytic growth, buta reduction in the concentration of available nitrogen was neededfor the development of shoots. ions alone were effective for gametophytic growth and the initiationof sporophytic shoots, but both and ions was required for the developmental phase. (Received February 18, 1992; Accepted April 14, 1992) 相似文献
75.
Masayuki Nakamichi Shinji Imakawa Yasuo Kojima Ayuko Natsume 《Primates; journal of primatology》1992,33(3):413-418
Parturition behavior of a multiparous female and her interactions with group members throughout the birth process were recorded
for a free-ranging Japanese monkey (Macaca fuscata). The female showed evidence of 18 contractions during the 35 min prior to delivery, with a mean duration and a mean intercontraction
interval of 30 sec and 96 sec, respectively. These values were similar to those in individually caged Japanese monkeys. Some
adult females remained in proximity to the female who was giving birth during the prepartum phase, and her 2-year-old daughter
watched the delivery of the infant. Even during the prepartum phase the female moved in order to keep up with the group which
traveled from the feeding site to a sleeping site in the forest. 相似文献
76.
The influence of grazing by water buffalo (Bubalas bufalis) and cattle (Bos taurus) was estimated for vegetation inside and outside cages in a saline area at Khon Kaen, Northeast Thailand.
The home range of water buffalo and cattle shifted in response to the period of rice cultivation: during the rice-growing
season these animals grazed on roadsides and abandoned places such as the study area; after rice harvest they grazed mainly
rice stubble on the paddy.
The vegetation in the study area was divided into three types: 1) dominated by the annual grassesChloris barbata andIschaemum rugosum; vegetational cover and plant height in the cage increase due to the increase of these grasses; 2) thorny shrub patch ofMaytenus mekongensis; other species in this patch almost died a year after experimental elimination of this shrub; this salt-tolerant shrub not
only protected the co-existing species from grazing, but also suppressed salt accumulation; 3) almost pure stand ofPanicum repens; livestock preferred this perennial grass over others.
Electrical conductivity (EC) of surface soil did not increase under the vegetation protected from grazing. Litter and other
organic matter in the soil suppressed the upward movement of brine. Grazing led to an increase of bare ground where NaCl accumulated,
and modified the heterogeneity of vegetation, which was reflected in the degree of salt accumulation. 相似文献
77.
Masayuki Taniguchi Mitsuo Tanaka Ryuichi Matsuno Tadashi Kamikubo 《Applied microbiology and biotechnology》1982,14(1):35-39
Summary Rice straw was treated with NaOH, peracetic acid (PA), and sodium chlorite (NaClO2). Quantitative changes in the composition of the treated straw, crystallinity of the treated straw and extracted cellulose, and susceptibility of the treated straw to Trichoderma reesei cellulase were studied. The alkali treatment resulted in a remarkable decrease in hemicellulose as well as lignin. Consequently, the recovery of residual straw after NaOH treatment was lowest among the three chemical reagents evaluated. The treatment with PA or NaCIO2 resulted in a slight loss in hemicellulose and cellulose in the straw. The three chemical treatments caused little or no breakdown of the crystalline structure of cellulose in the straw. The treated straw was solubilized with the culture filtrate of T. reesei. The degree of enzymatic solubilization relative to the amount of residual straw was 69% after treatment with 0.25 N NaOH, 42% after treatment with 20% PA, and 50% after treatments with NaClO2 (twice). The degree of enzymatic solubilization relative to the amount of the untreated straw, however, was 30% after treatment with 0.25 N NaOH, 32% after treatment with 20% PA, and 37% after treatments with NaClO2 (twice). 相似文献
78.
Morphological, cytological and ecological observations were made onLycopodium clavatum. Among 121 individuals from 26 populations studied 31 were of the diploid cytotype with 2n=68, 45 were of the triploid cytotype
with 2n=102 and 45 were of the tetraploid cytotype with 2n=136. The populations were divided into three types: (1) the sole
type—characterized by a single cytotype occupying an entire population, (2) the mixed type A—characterized by two or three
cytotypes occupying together the same population, but each cytotype choosing different habitats, (3) the mixed type B—characterized
by two or three cytotypes occupying together the same population and sharing the same habitat with each other. The mixed type
B populations were found in the places of the early phase of secondary succession in a plant community. In the sole type and
the mixed type A, the habitat preference for each cytotype was described as follows: the habitat for the diploid was in humid
and shady places, that for the tetraploid was in open and sunny, unstable places, and that for the triploid was intermediate
between the other two. Each cytotype can progress towards occupying their optimum habitat successively from the mixed type
B population to the mixed type A population and finally reaching the sole type population. 相似文献
79.
Akitane Mori Masayuki Akagi Yasuto Katayama Yoko Watanabe 《Journal of neurochemistry》1980,35(3):603-605
: Guanidino compounds in the cobalt-induced epileptogenic cerebral cortex of cats were fluorometrically analysed by a JASCO G-520 guanidino compounds analyser, and an unknown high peak was observed in the chromatogram that was identical to the peak of authentic α-guanidinoglutaric acid. In another experiment, the substance was extracted from the cobalt focus tissue, converted into dimethylpyrimidyl derivative-butylester, and analysed by a GC/MS technique. The mass spectrum of the substance was identical to the dimethylpyrimidyl derivative of α-guanidinoglutaric acid butylester (M+= 365). 相似文献
80.