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941.
目的:克隆嗜热毁丝霉(Myceliophthora thermophila ATCC42464)bglr基因,构建Mtbglr过表达载体,研究同源过表达bglr对嗜热毁丝霉β-葡萄糖苷酶活性及总纤维素酶活性的影响。方法:利用SLIC技术构建Mtbglr过表达载体;使用MtPpdc启动子及MtTpdc终止子将该基因进行同源过表达;利用原生质体转化、实时荧光定量PCR和酶活测定等技术实现bglr基因在嗜热毁丝霉中表达及酶活水平的鉴定。结果:成功构建Mtbglr过表达载体,并转化嗜热毁丝霉,结果表明,诱导培养条件下,转化子Mt8菌株的β-葡萄糖苷酶活性和胞外蛋白质浓度分别是WT菌株的1.7倍和1.9倍。结论:bglr基因对嗜热毁丝霉β-葡萄糖苷酶活性具有增强作用,为嗜热真菌β-葡萄糖苷酶基因调控奠定了理论基础。  相似文献   
942.
Ectomycorrhizal fungi (ECM) are a fundamental component of boreal forests promoting tree growth and participating in soil nutrient cycling. Increased nitrogen (N) input is known to largely influence ECM communities but their potential recovery is not well understood. Therefore, we studied the effects of long-term N-fertilisation on ECM communities, and their recovery after termination of N treatment. Fungal ITS sequencing data indicated that N-fertilisation (34 kg N ha−1 y−1) for 46 y decreased the relative abundance of ECM species in the fungal community and suppressed originally dominating medium-distance fringe exploration types adapted to N-limited conditions, while the ECM diversity remained unaffected. In other plots, 23 y after termination of fertilisation at 73 kg N ha−1 y−1 for 23 y, the relative abundance of ECM species shifted closer to, but did not reach, control levels. These observations indicate only slow recovery of ECM community, likely due to a high soil N retention capacity.  相似文献   
943.
We asked if exotic Pinus elliotti seedlings can survive and form ectomycorrhizas at higher elevations and long distances from their current range, and which ECM partners disperse to these soils. We selected three plots at four grassland sites along an altitudinal gradient (900, 1600, 2200, and 2700 m asl) established at c. 110, 3000, 6000, and 9000 m from the closest pine plantation, respectively. We combined field experiments with glasshouse assays to assess survival and ECM fungi in roots and soils. A pine plantation close to the lowest site was also selected for DNA metabarcoding of soils. Pine seedlings survived at all altitudes but not all formed mycorrhizas. They formed mycorrhizas with Suillus granulatus at 900, 1600, and 2200 m asl (i.e. up to 6000 m from the closest pine plantation), and with Rhizopogon pseudoroseolus and Thelephora terrestris at lower altitudes and distances. Twelve ECM fungal OTUs were found in grasslands and 34 were detected in the pine plantation. Although richness and abundance of ECM fungi decreased with increasing distance from the pine plantation, there was at least one non-native ECM fungal species present in each sampling site, even at 2700 masl and 9000 m distance from the closest plantation. This study provides evidence that the availability of suitable fungal symbionts might constrain but not hinder the expansion of a pine species over wide distances and altitudinal zones even in areas with no native ECM fungi.  相似文献   
944.
Biodiversity surrogates are commonly used in conservation biology. Here we review how fungi have been used as such in forest conservation, emphasizing proposed surrogate roles and practical applications. We show that many fungal surrogates have been suggested based on field experience and loose concepts, rather than on rigorously collected scientific data. Yet, they have played an important role, not only in forest conservation, but also in inspiring research in fungal ecology and forest history. We argue that, even in times of ecosystem oriented conservation planning and molecular tools to analyze fungal communities, fruit bodies of macrofungi have potential as convenient conservation shortcuts and easy tools to communicate complex biodiversity for a broader audience. To improve the reliability of future fungal surrogates we propose a three step protocol for developing evidence based schemes for practical application in forest conservation.  相似文献   
945.
Three new pterocarpon flavonoids, wisterones B-D, together with nine isoflavone known compounds, were isolated from Wisteria sinensis Tumor. The structure of those compounds were elucidated on the basis of spectroscopic analyses, including UV, IR, MS and NMR experiments. These new compounds were investigated for their activities against anti-crop pathogenic fungi.  相似文献   
946.
Predation is a powerful selective force with important effects on behavior, morphology, life history, and evolution of prey. Parasites may change body condition, health status, and ability to escape from or defend prey against predators. Once a prey individual has been detected, it can rely on a diversity of means of escape from the pursuit by the predator. Here we tested whether prey of a common raptor differed in terms of fungi from nonprey recorded at the same sites using the goshawk Accipiter gentilis and its avian prey as a model system. We found a positive association between the probability of falling prey to the raptor and the presence and the abundance of fungi. Birds with a specific composition of the community of fungi had higher probability of falling prey to a goshawk than individual hosts with fewer fungi. These findings imply that fungi may play a significant role in predator–prey interactions. The probability of having damaged feathers increased with the number of fungal colonies, and in particular the abundance of Myceliophthora verrucos and Schizophyllum sp. was positively related to the probability of having damaged feathers. In addition, we found a significant correlation between the rate of feather growth of goshawk prey with birds with more fungi being more likely to be depredated. These findings are consistent with the hypothesis that survival and feather quality of birds are related to abundance and diversity of fungi.  相似文献   
947.
This contribution describes the deposition of gold nanoparticles by microbial reduction of Au(III) ions using the mycelium of Mucor plumbeus. Biosorption as the major mechanism of Au(III) ions binding by the fungal cells and the reduction of them to the form of Au(0) on/in the cell wall, followed by the transportation of the synthesized gold nanoparticles to the cytoplasm, is postulated. The probable mechanism behind the reduction of Au(III) ions is discussed, leading to the conclusion that this process is nonenzymatic one. Chitosan of the fungal cell wall is most likely to be the major molecule involved in biomineralization of gold by the mycelium of M. plumbeus. Separation of gold nanoparticles from the cells has been carried out by the ultrasonic disintegration and the obtained nanostructures were characterized by UV‐vis spectroscopy and transmission electron micrograph analysis. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:1381–1392, 2017  相似文献   
948.
杨顺  孙微  刘杏忠  向梅春 《生物多样性》2016,24(9):1068-125
石生真菌是一类生长在裸露岩石上形成紧凑暗色菌落的特殊生命, 在自然界未发现其有性生殖结构, 它们具有丰富的物种多样性。石生真菌是地球上最具耐受力的一种真核生命, 具有独特的适应性, 并进化出各种适应机制以占据严酷的生态位, 它们在细胞结构、代谢方式、抗逆机制等方面具有特殊性。尽管石生真菌很常见,但由于其体积小、生长缓慢并且缺乏明显的形态特征而常常被人们忽视。本文在介绍石生真菌的多样性、研究方法和研究历史的基础上, 重点介绍石生真菌的逆境耐受性和抗逆机制以及石生真菌的应用研究。以期能引起科学工作者对这类特殊生境里的真菌研究的重视, 更好地理解这类真菌在地球上的重要作用。  相似文献   
949.
工业真菌是酶制剂的重要生产微生物,其菌种改良具有重要应用价值。综述了产酶工业真菌的应用、突变育种技术进展和高效产酶机制的分析策略,尤其是基于组学水平的基因组、转录组和蛋白质组的分析等,最后总结了高产机制在菌株改良上的应用。  相似文献   
950.
黑木耳复合群中种类学名说明   总被引:2,自引:0,他引:2  
吴芳  戴玉成 《菌物学报》2015,34(4):604-611
黑木耳在我国已经有1 000多年栽培历史,是我国最重要的栽培真菌之一,多年来我国黑木耳的学名一直使用模式产地为欧洲的Auricularia auricula-judae。最近的研究表明A. auricula-judae实际为一复合种,该复合种在全球范围内有5个种。其中A. auricula-judae仅分布于欧洲;美洲有2个种,生长在针叶树上的美洲木耳A. americana和生长在阔叶树上的尚未命名的木耳。中国该类群有3个种:自然分布和栽培最广泛的黑木耳的学名应为A. heimuer,此外,短毛木耳A. villosula在我国东北也广泛分布,并有少量栽培,生长针叶树上的木耳为美洲木耳A. americana,主要分布于中国东北和华北。  相似文献   
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