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21.
虫花菌(Isaria farinosa(Dicks)Fr.)发酵液经超滤浓缩、乙醇沉淀、弱酸性阳离子交换树脂和弱碱性阴离子交换树脂去杂蛋白后,又经Sephadex G-150纯化得到PG。PG经醋酸纤维膜电泳、聚丙烯酰胺凝胶电泳和Sepharose 4B柱层析,证明是单一均匀的糖蛋白。PG的分子量为11.1万。PG的糖含量为92.35%、蛋白含量为7.61%。PG用气相色谱、红外光谱分析表明含有D-甘露糖、D-半乳糖,其摩尔比是5.93:1。推测PG主要含α-型糖苷键。PG对小鼠实体瘤S-180有一定的抑制作用,抑瘤率为22.2%。  相似文献   
22.
几种担子菌胞外漆酶同工酶谱的研究   总被引:3,自引:0,他引:3  
从猴头(Hericium erinaceus)、亚侧耳(Hohenbuehelia serotina)、毛柄金钱菌(Co-llybia velutipes)、多脂鳞伞(Pholiota adiposa)、香菇(Lentinus edodes)、黑木耳(Auriculariaauricula)、草菇(Volvaria volpacea)二孢蘑菇(Agaricus bisporus)和紫孢侧耳(Pleurotussapidus)、侧耳(Pleurotus ostreatus)风尾菇(P.sajor-caju)、金顶侧耳(P.citrinopileatus)、鲍鱼菇(P.cystidiosus)、佛罗里达侧耳(P.florida)、爪哇漏斗状侧耳(P.sajor-caju var.javanicus)商品化菌种的培养滤液里所得到的胞外漆酶(LC),采用聚丙烯酰胺凝胶等电聚焦盘状电泳方法,分析比较了它们的胞外漆酶同工酶。经多批次比较试验,获得了侧耳属七个种和八个不同属间各自恒定的漆酶同工酶谱。在这些酶谱中,分别包含了 A 组(pH3—5)和 B 组(pH5—8)的谱带。而且,所有菌种间漆酶带的等电点值(pI)各有异同。没有测定菌种间各漆酶带含量差别。讨论了漆酶同工酶谱用于分类研究的可能性。  相似文献   
23.
Protoplasts of the ectomycorrhizal ascomycete Cenococcum geophilum were isolated from mycelium grown in liquid medium. The method was optimized with regard to culture conditions, preincubation, lytic enzyme system, pH value of the incubation medium, osmotic buffer and incubation temperature for C. geophilum strains SIV and 1448. The yields were 1-3·108 and 7·106 protoplasts per gram fresh weight for C. geophilum SIV and C. geophilum 1448, respectively. Protoplasts from C. geophilum SIV exhibited plasma membrane integrity close to 100% (fluorescein diacetate staining). At least 50% of the protoplasts contained a nucleus (staining with acridine orange). The regeneration of protoplasts from C. geophilum is described for the first time. The regeneration frequency was up to 13%, and, dependent on the conditions of culture (liquid medium, agarose, agar), four types of regeneration patterns could be distinguished Regenerated protoplasts of C. geophilum were capable of forming mycorrhizas with spruce (Picea abies) seedlings.  相似文献   
24.
Summary Phosphorus-31 nuclear magnetic resonance spectra at 36.4 MHz are presented for intact ectomycorrhizal fungi grown in pure culture. Resonances from polyphosphates and intracellular orthophosphate are identified inCenococcum graniforme, Hebeloma cylindrosporum, andH. crustuliniforme. Comparison of the NMR spectra with phosphorus fractionation of the fungi extracts leads to the statement that the NMR-observed polyphosphaes is a good part of the accumulated polyphosphates. In actively growing mycelia, this fraction account for up to 17% of total P.  相似文献   
25.
Hormonal effect on glycoproteins and glycosaminoglycans in rabbit uteri   总被引:1,自引:0,他引:1  
The effect of the female hormones on glycoproteins and glycosaminoglycans in uteri has been studied.The uteri taken from the ovariectomized rabbits treated with estrogen, estrogen plus progesterone, and sham administration (control) were incubated in vitro with [U-14C]glucose. Subsequently, the tissues were digested extensively with pronase, yielding crude glycan fractions. The amount and radioactivity of the crude glycan fraction increased by the treatment with estrogen, but reduced to certain level with progesterone.Separation of glycoproteins and glycosaminoglycans was achieved by stepwise elution from Dowex 1 (X2, chloride form) with increasing concentration of NaCl. The yield and radioactivity, together with the results of chemical, enzymatic, and electrophoretic studies on the resulting fractions indicated that the metabolism of a slightly acidic glycoprotein, hyaluronic acid, sulfated glycoproteins, low-sulf ated chondroitin sulfate, heparan sulfate, chondroitin 4-sulfate, and dermatan sulf ate were stimulated remarkably with estrogen, but the stimulation was restored to certain level with progesterone. The degree of the change with these hormones was, however, found to be different from each other. It was noticed that sulfated glycoproteins were the most sensitive to the hormones. On the other hand, the estrogenic stimulation of the metabolism of a neutral glycoprotein and oversulfated chondroitin sulfates was not restored with progesterone.  相似文献   
26.
云南松(Pinus yunnanensis Fr.)在小孢子囊发育早期,绒毡层原生质体发生收缩,并伴随着细胞壁厚度的增加。脂肪微滴和孢粉素物质沉积而形成周缘绒毡层膜。随着孢粉素物质的产生,绒毡层细胞质明显地液泡化。孢粉素物质在绒毡层细胞膨大的内质网槽库中形成,随后被排放到近邻的小液泡内或游离于细胞质中。孢粉素物质也可在特化的含片层的质体中形成,孢粉素依附在片层膜上,或释放到细胞质中。  相似文献   
27.
K-bearing minerals with enormous reserve in the world, were not easy to provide the available K nutrient element for plant direct uptake because of the slow K release rate. With the potential potassium-solubilizing microorganisms, the slow K release rate from minerals would be improved significantly. In this work, Cenococcum geophilum Fr, one of the most common ectomycorrhizal fungi in boreal to temperate regions, was adopted to dissolve K-bearing minerals for K release. Five kinds of potassium aluminosilicate minerals were tested by bioleaching experiments in pure culture, including feldspar, nepheline, biotite, muscovite and illite. The available and unavailable potassium amounts in minerals before and after bioleaching were measured and compared with each other. The effect of mineral structure on the potassium solubilization efficiency by Cenococcum geophilum Fr. was discussed. Furthermore, the microenvironment formation between fungi and mineral surface to enhance the K release rate was investigated through detecting K, Al, Si concentrations and metabolites amounts (polysaccharide and organic acids) in microenvironment and external environment, respectively. Experimental results demonstrated that Cenococcum geophilum Fr. was a potential candidate of potassium solubilizing microorganisms, and both mineral structure and microenvironment have significant effects on the K release rate.  相似文献   
28.
  • 1 Weevil larvae of the genus Otiorhynchus are a serious problem in agriculture and forestry, causing damage to a wide range of plant species, primarily by larval feeding on roots. Otiorhynchus larvae are a serious pest in forest plantations in Iceland, causing 10–20% mortality of newly‐planted seedlings.
  • 2 We studied the effects of soil fungi on the survival of Otiorhynchus sulcatus larvae. The larvae were introduced into pots with birch seedlings grown in: (i) nursery peat; (ii) nursery peat inoculated with three different species of ectomycorrhizal fungi; (iii) nursery peat inoculated with insect pathogenic fungi; (iv) nursery peat inoculated with ectomycorrhizal fungi and insect pathogenic fungi; and (v) nursery peat inoculated with natural forest soil from Icelandic birch woodland.
  • 3 Larval survival was negatively affected by inoculation of: (i) the ectomycorrhizal fungus Laccaria laccata; (ii) the ectomycorrhizal fungus Cenococcum geophylum; (iii) the insect pathogenic fungus Metarhizium anisopliae; and (iv) forest soil. Inoculation with the ectomycorrhizal fungus Phialophora finlandia did not have any significant effect on larval survival. No significant synergistic effect was found between insect pathogenic and ectomycorrhizal fungi.
  • 4 It is concluded that ectomycorrhizal and insect pathogenic fungi have a significant potential in biological control of Otiorhynchus larvae in afforestation areas in Iceland. Further studies are needed to establish the effect of these fungi in the field and to analyse how mycorrhizal fungi affect root‐feeding larvae.
  相似文献   
29.
Forest trees are involved in root symbioses with hundreds of species of ectomycorrhizal fungi which constitute functional guilds able to improve the water and mineral nutrition of host trees. In temperate ecosystems, water shortage is a main factor limiting tree vitality. To assess how soil water conditions affected the physiological state of beech (Fagus silvatica L.) ectomycorrhizal roots, we monitored glucose respiration of two ectomycorrhizal types (Lactarius sp. and Cenococcum geophilum) during two complete growing seasons. Five stands of contrasting soil conditions were chosen in north-eastern France. The top soil horizons were equipped with micropsychrometers for measuring water potential and temperature. Glucose respiration on individual ectomycorrhizas was measured in vitro by trapping [14C]-CO2 from radiolabelled glucose. For soil water potential <-0.2 MPa, the potential respiration activity of C. geophilumectomycorrhizas was significantly less altered than that of Lactariussp. ectomycorrhizas, indicating that C. geophilumis more likely than Lactariussp. to maintain the physiological integrity of beech roots facing drought stress.  相似文献   
30.
Castanopsis fissa Rehd. & Wils. is widely distributed from the tropics to the temperate regions of China and Japan and is an important forest component in Hong Kong. Pot-grown C. fissa seedlings inoculated with vegetative mycelial inocula of seven ectomycorrhizal fungi for 20 weeks were analysed for growth performance and mineral nutrient uptake of N, P, K and Ca. Shoot growth stimulation in all fungal treatments generally occurred in the first 4–8 weeks of seedling development. Uptake of P was generally enhanced by all fungi inoculated. Seedlings inoculated with Pisolithus tinctorius (Pers.) Coker and Couch and Cenococcum geophilm (Sow.) Fredinard et Winge, which colonized 22% and 33% of roots respectively, exhibited growth stimulation. The results indicate that P. tinctorius and C. geophilum are suitable for use in large-scale nursey inoculation.  相似文献   
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