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91.
在灵芝TW液体深层富碘培养过程中,碘元素能显著提高灵芝菌丝体中氨基酸的含量,不富碘的灵芝菌丝体氨基酸含量为26.95%,在培养基中添加0.1%碘化钾而获得的富碘灵芝菌丝体及富碘锌锗硒灵芝菌丝体氨基酸含量分别为35.37%、35.86%,另外其氨基酸的组成也相对发生了显著的变化,因而推测碘元素可能是灵芝中某些氨基酸含成过程中的辅基或是其激活因子。  相似文献   
92.
运用建立的高效液相色谱条件,首次实现在完成灵芝孢子粉中麦角甾醇含量测定的同时,对灵芝孢子粉中脂溶性成分的指纹图谱进行研究。结果表明,该方法测定麦角甾醇准确、稳定、特异性好,脂溶性成分指纹图谱基线平直、色谱峰丰富且具备较好的分离度,该方法适合在分析测定灵芝孢子粉中麦角甾醇(282nm)含量的同时,对其脂溶性成分(245nm)的指纹图谱进行分析,为整体评价灵芝孢子粉及其产品的质量提供依据。运用建立的方法对收集的各孢子粉样品进行分析,表明破壁与否及破壁时间长短对灵芝孢子粉中麦角甾醇及脂溶性成分的溶出有显著的影响,实验认为最佳的破壁时间为20-30min;低温冻藏可以有效地保护样品中的成分;随着产粉时间的延长,孢子粉中麦角甾醇的含量变化不大,脂溶性成分总体上有所增加;不同原料来源孢子粉中麦角甾醇的含量和脂溶性成分指纹图谱的差异都很大,且麦角甾醇的含量与指纹图谱色谱峰的丰富程度没有一定的相关性,因此不能仅以麦角甾醇的含量来表征灵芝孢子粉的质量,二者的综合分析对灵芝孢子粉质量的评价才更有意义。  相似文献   
93.
A new epoxidic ganoderic acid, 8α,9α-epoxy-3,7,11,15,23-pentaoxo-5α-lanosta-26-oic acid (1), together with the known compounds 3β-hydroxy-7,11,15,23-tetraoxo-5α-lanosta-8-en-26-oic acid (2), ergosta-7,22-diene-3β-yl pentadecanoate (3), ergosta-7,22-diene-3β-ol (4), β-sitosterol (5), fatty acids (610), fatty acid ester (11) and octadecane (12) were isolated from the fruiting bodies of Ganoderma lucidum from south India. Their structures were determined by 1H, 13C, 13C DEPT, 1H–1H COSY, HMBC, HSQC, NOESY NMR, FT-IR, UV–vis and FABMS spectral analysis. Compounds (13) exhibited good antifungal activity against Candida albicans in disc diffusion assay (100 μg/disc). Steroid ester (3) showed moderate anti-inflammatory activity (59.7% inhibition, 100 mg/kg body weight) in carrageenan-induced paw edema.  相似文献   
94.
1 Competitive interactions among two specialist predators, Laricobius nigrinus and Sasajiscymnus (Pseudoscymnus) tsugae, and a generalist predator, Harmonia axyridis Pallas, of hemlock woolly adelgid, Adelges tsugae were evaluated in hemlock stands in south‐western Virginia. The two specialist predators are part of a biological control program for A. tsugae, and the potential for competition among these species and previously established generalist predators in the field is unknown. 2 Adult predators were evaluated in branch cages during spring and summer at two field sites infested with A. tsugae. Using females only in 2003 and sexual pairs in 2004, predator survival and net reproduction were examined, as well as their feeding and impact on A. tsugae when present alone and in conspecific and heterospecific groupings. 3 Predator survival was not affected by the presence of additional predators. Total feeding was greater for all species when placed in predator groupings, suggesting that interactions do not significantly interfere with feeding activity. Net reproduction per predator was negatively affected by conspecifics, but unaffected by heterospecifics, indicating that direct or indirect intraspecific interference may occur. In spring, L. nigrinus showed the greatest impact on A. tsugae, and H. axyridis had the greatest impact during summer. 4 These results suggest that it would be beneficial to utilize multiple predator species combinations over single species when implementing biological control for A. tsugae. Low‐density releases are also recommended to reduce intraspecific interference.  相似文献   
95.
灵芝发酵菌丝体中灵芝酸的分离纯化及生物活性检测   总被引:11,自引:0,他引:11  
灵芝深层发酵菌丝体经甲醇提取得到粗灵芝酸,以甲苯:乙酸乙酯:乙酸(12:4:0.5)为展开剂,通过硅胶薄层层析法分离得到三种灵芝酸,命名为M_1,M_2和M_3,其R_f值分别为0.56,0.49,0.17.在优化的硅胶柱层析条件下,即以CH_3OH:CHCl_3=3:97,5:95,1:9为洗脱剂,进行分段洗脱;进样量:硅胶量=1:60;在30m×500mm的层析柱上纯化得到三种灵芝酸.抗菌实验显示,三种四环三萜酸具有抑制大肠杆菌、产气杆菌、肠炎杆菌、金黄色葡萄球菌和枯草芽孢杆菌生长的活性.  相似文献   
96.
通过对灵芝菌As5.504发酵,研究不同糖源、氮源、生长因子及接种量、装液量对灵芝细胞生长和灵芝多糖生产的影响。结果表明当以葡萄糖,蛋白胨,VB5分别为碳源、氮源、生长因子及接种量、装液量分别为7.5mL、150mL时,为As5.504产多糖最佳发酵工艺条件,产多糖量最高为0.940g·L-1。  相似文献   
97.
以甘蔗纤维作为灵芝菌丝固定载体,通过扫描电子显微镜观察确定载体固定时间,通过液体发酵灵芝菌丝球大小形态、生物量、胞外多糖和胞外三萜含量确定载体形状、大小与数量。结果表明,灵芝菌丝在载体上固定时间为7d,载体为1.5cm×1.5cm(直径×高度)的圆柱体小块(Y1.5),接种数量6块,可连续稳定发酵7代。以甘蔗纤维固定发酵制备灵芝液体发酵种子,发酵后菌丝球大小均一,生物量、胞外多糖含量和三萜含量分别提高78%、84%和60%。  相似文献   
98.
Ganoderma leucocontextum is a well‐known medicinal mushroom cultivated in the Tibet Plateau of China. Chemistry investigation on the fruiting bodies of this mushroom resulted in the isolation of sixteen secondary metabolites including three new lanostane triterpenes, ganoleucoins Q – S ( 1 – 3 ), as well as thirteen known compounds ( 4 – 16 ). The structures of compounds 1 – 3 were determined by NMR, MS, CD spectral analysis, and chemical derivation method. The neuroprotective effects of compounds 1 – 16 were tested on PC12 cells. Compounds 1 and 2 showed protective effects against the H2O2 induced damage with the survival rate of 83.19 ± 0.92%, 73.37 ± 1.25% at the concentration of 200 μm , respectively. Meanwhile, compounds 1 and 2 induced neurite outgrowth at 50 – 200 μm . The results from this study suggested that G. leucocontextum and its metabolites may be potential functional food ingredients for the prevention of neurodegenerative diseases.  相似文献   
99.
灵芝多糖对人脐血LAK细胞活性的影响   总被引:2,自引:0,他引:2  
徐新  曹容华 《生物技术》1994,4(2):33-35,23
本文研究了灵芝多糖(GLP)对人脐血LAK(CB—LAK)细胞活性的影响,结果发现,单独GLP能刺激人脐血单个核细胞(CBMC)增殖,但不能诱导LAK活性,当与50u/mlrIL—2伍用时,可增殖CB—LAK细胞诱导活性,不同剂量GLP(0.5—100μg/ml)影响作用不同,以10μg/ml浓度最好.在不同浓度rIL—2(10—100u/ml)诱导CB—LAK细胞过程中加入GLP(10μg/ml),可明显提高细胞增殖能力,减少rIL—2用量。GLP亦能促进效应阶段CB—LAK细胞对Raji肿瘤靶细胞的杀伤作用(P<0.001)。由此看出,GLP具有增强CB—LAK细胞活性的作用,是一很好的生物反应调节剂(BRM),有必要进行深入的研究。  相似文献   
100.
Ganoderma boninense is a white rot basidiomycete that causes basal stem rot disease of oil palm (Elaeis guineensis). The aims of this study were to identify endophytic basidiomycetes occurring naturally within oil palm and to assess their potential as biocontrol agents against G. boninense strain PER71 in vitro. In total, 376 isolates were recovered from samples collected from the root, stem and leaves of oil palm using Ganoderma‐selective medium. Ten of these isolates (2.7% of the total 376 isolates) were identified as basidiomycetes on the basis of clamp connections and the production of poroid basidiomes after incubation in glass jars containing PDA medium for 7–12 days. The isolates were identified using ITS rDNA sequencing as Neonothopanus nambi (five isolates), Schizophyllum commune (four isolates) and Ganoderma orbiforme (one isolate). The N. nambi isolates showed the greatest antagonistic activity against G. boninense, based on 73–85% inhibition of the radial growth measurements of G. boninense in dual culture and 76–100% inhibition of G. boninense growth in a culture filtrate assay. Possible modes of action for the antagonism shown by N. nambi against G. boninense in vitro include competition for substrate availability, space and the production of non‐volatile metabolites or antibiotics that inhibited the growth of G. boninense. Further in vivo investigations are required to determine the ability of N. nambi isolates to colonize oil palm seedlings and to protect oil palm from infection when challenged with G. boninense.  相似文献   
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