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1.
Konno, H., Yamasalu, Y. and Katoh, K. 1987. Fractionation andpartial characterization of pectic polysaccharides in cell wallsfrom liverwort (Marchantia polymorpha) cell cultures.—Jexp. Bot. 38: 711–722. Pectic polysaccharides were extracted from the starch-free cellwall preparation of cell suspension cultures of Marchantia polymorpha.The polysaccharides were fractionated by DEAE-Sephadex A-50ion-exchange chromatography yielding the five fractions, andthe degree of polymerization and glycosyl composition determinedfor each fraction. The neutral rich and acidic pectic polymerswere depolymerized by purified endoglucanase (l,4-ß-D-glucan4-glucanohydrolase, E.C. 3.2.1.4 [EC] .) and endopolygalacturonase(poly-l,4--Dgalacturonide glycanohydrolase, E.C. 3.2.1.15 [EC] ),respectively. The degraded pectic fractions were fractionatedby gel filtration chromatography on Bio-Gel A-5m and Bio-GelP-2, and glycosyl composition determined for each fraction.The results indicate that pectic polysaccharides contain glucose-richpolymer, rhamnogalacturonan and homogalacturonan in a ratioof 1:4:0–6. In addition, pectic polysaccharides were releasedas five pectic fragments from the cell walls by purified endopectatelyase (poly-l,4--D-galacturonide lyase, E.C. 4.2.2.2 [EC] ). Basedon the analysis of glycosyl composition of each fragment, thepectic polysaccharides of Marchantia cell walls are characterized Key words: Cell suspension culture, cell wall, liverwort, Marchantia polymorpha, pectic polysaccharides  相似文献   
2.
The society finch, a little passerin, was purposed to be utilized in embryological studies. Under control of the breeding cycle in 20 pairs, 4 to 6 eggs were used to be laid daily for several repeating week in a year. Average incubation time was 17 days in contrast to 21 in the domestic fowl. The eggs weighed 1.1 g in average and expected smallness of the embryo was regarded as favorable for morphological studies including the scanning electron microscopy. We present the first report of the complete development of the society finch. A number of embryological characteristics are described with special reference to the peculiarity of the altricial finch as compared with the precocial domestic fowl.  相似文献   
3.
C-9-1, a monoclonal IgM antibody raised against human null cell acute lymphocytic leukemia cells reacted with restricted regions of embryonic and adult tissues of the mouse. The antigen positive sites in the embryos included embryonic ectoderm, visceral endoderm, trophoblastic cells invading the maternal decidua of 5∼7-day embryos, primordial germ cells of 10∼12-day embryos, epithelium of nasal chamber, the bronchus, Mullerian duct, epididymis and bladder of 12∼17-day embryos. In the adult mice, C-9-1 antigen was detected in renal tubules, a part of stomach, bladder, endometrium and epididymal sperm. Embryonal carcinoma cells, but not endodermal cells of teratocarcinoma expressed the antigen. Thus, C-9-1 antigen showed distribution similar to SSEA-1. However, C-9-1 antigen was not detected in preimplantation embryos, nor in oviduct, both of which are positive for SSEA-1.  相似文献   
4.
When dark grown cells of Chlamydomonas reinhardtii y-1 mutantwere exposed to continuous light, an immediate transformationof small amounts of protochlorophyll(ide), which had been presentin the dark grown cells, to chlorophyll was observed. Afterthis, there was a slow accumulation of chlorophyll lasting for2.5-3 hr before the start of exponential synthesis. Initialaccumulation of chlorophyll was distinctly slower at a highlight intensity (13,000 lux) than it was at moderate intensitiesof light (2,000–5,000 lux). However, the exponential synthesisof chlorophyll started after the same 2.5–3 hr of illumination. A brief pre-illumination of cells followed by incubation indarkness was effective in promoting chlorophyll synthesis undersubsequent continuous illumination at high, as well as moderatelight intensities. Pretreatment alleviated retardation of theinitial chlorophyll accumulation by light of high intensity.The promoting effect of preillumination on chlorophyll synthesiswas sufficient, even when a light impulse as short as 10 secwas given. However, the effect was dependent on length of thedark period after the short pre-illumination. The full extentof this effect was observed when the dark period was about 2.5–3hr long. Further dark incubation gradually decreased the effect. On the basis of these findings, it is assumed that a factor(s)responsible for promotion of chlorophyll (or chloroplast) synthesisin the process of greening of dark grown cells is produced duringthe dark period after a brief pre-illumination, and that thefactor is turned over at a relatively fast rate. The possiblenature of the presumed factor is discussed in relation to chloroplastdevelopment. 1Present address: Department of Biology, Faculty of Science,Kobe University, Nada-ku, Kobe, Japan. (Received August 18, 1970; )  相似文献   
5.
Isocitrate lyase was purified to homogeneity from ethanol-grown Euglena gracilis. The specific activity was 0.26 μmol/min/mg protein. The molecular mass of the enzyme was calculated to be 380 kDa by gel filtration on a Superose 6 column. The subunit molecular mass of the enzyme was 116 kDa as determined by SDS-polyacrylamide gel electrophoresis. These results showed that the native form of this enzyme was a trimer composed of three identical subunits. The pH optimum for cleavage and condensation reactions was 6.5 and 7.0, respectively. The Km values for isocitrate, glyoxylate and succinate were 3.8, 1.3 and 7.7 mM, respectively. Isocitrate lyase absolutely required Mg for enzymatic activity. This is the first report of the purification of isocitrate lyase to homogeneity from Euglena gracilis.  相似文献   
6.
We analyzed the spatial distributions of two congeneric tree species, Neolistea aciculata and Neolistea sericea (Lauraceae), in a warm‐temperate forest on Miyajima Island, south‐western Japan. Both species were mainly found in valley sites on the island. Hence, these species shared the same topographic habitat niche. However, we found a clear difference between the spatial distributions of the two species in relation to the light environment. Neolistea aciculata was predominantly found in stands with low light, such as beneath the canopy of dense evergreen broadleaved forest. In contrast, N. sericea was predominantly associated with ample light, such as in secondary Pinus densiflora forest. In stands with moderate light conditions, both species were found. This habitat niche segregation in relation to light conditions presumably allows the coexistence of these two species in the predominantly successional forest on Miyajima Island.  相似文献   
7.
We developed 10 polymorphic microsatellite loci for the Japanese paper wasp Polistes rothneyi using the magnetic particle method. Eight of the 10 loci tested were highly polymorphic, having four to eight alleles in P. rothneyi with an expected heterozygosity of 0.60–0.75. They also appeared to be applicable to other related species such as Polistes jokahamae. These loci can be used to study parameters concerning genetic relatedness such as worker reproduction and kin structure.  相似文献   
8.
In Polistes paper wasps, haploid early males can mate with early emerging females and leave viable offspring. In contrast, diploid early males are eventually sterile because they contribute triploid offspring via diploid sperm. Clarifying the ploidy of early males is important for determining whether early male production is a reproductive strategy for the species. We examined the mating behavior and the ploidy of early males in the Japanese paper wasp, Polistes rothneyi iwatai van der Vecht. Thirteen early males from four colonies were all diploid. Two of the nine early males (22.2%) attempted to mate with females, but only one individual (11.1%) was successful (the female's spermatheca contained spermatozoa). These results suggest that although most early males of P. rothneyi iwatai do not produce offspring, their mating may be linked to the occasional production of triploid females.  相似文献   
9.
10.
ABSTRACT. The Gram-negative bacterium Holospora obrusa is a macronucleus-specific symbiont of the ciliate Paramecium caudatum. The infectious form of this bacterium infects the host macronucleus through digestive vacuoles and differentiates into the reproductive form two days after the infection in the nucleus. The monoclonal antibodies IF-3–1 and IF-3–2 reacted with 39 and 1S kDa periplasmic proteins, respectively, that were specific for the infectious form of H. obrusa. Because the antigens were not detected in the reproductive form of the bacterium, it appears that expression of the proteins decreases during or soon after the infection. Using these antibodies, quantitative changes in the antigens in the early infection process were examined by immunoblotting and immunogold electron microscopy. Immunoblotting showed that the amounts of both antigens were reduced within 1 h after the bacteria were engulfed into the digestive vacuoles of the paramecia, but that the amounts of IF-3–2 antigens declined earlier than the IF-3–1 antigen. Immunogold labeling showed that the level of IF-3–2 antigens became very low in the bacteria in the host digestive vacuoles, whereas there was no similar decrease in amount of IF-3–1 antigens. Possible functions of the antigens are discussed. The IF-3–1 antigens decrease in concentration in parallel with the decrease in the periplasmic region.  相似文献   
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