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Min Cheng Yongyan Chen Dake Huang Wen Chen Weiping Xu Yin Chen Guodong Shen Tingjuan Xu Gan Shen Zhigang Tian Shilian Hu 《Aging cell》2020,19(2)
Cancer is an age‐associated disease, potentially related to the altered immune system of elderly individuals. However, cancer has gradually decreased incidence in the eldest globally such as the most common lung cancer, the mechanisms of which remain to be elucidated. In this study, it was found that the number of lung‐resident γδT cells was significantly increased with altered gene expression in aged mice (20–24 months) versus young mice (10–16 weeks). Aged lung Vγ4+ and Vγ6+ γδT cells predominantly produced interleukin‐17A (IL‐17A), resulting in increased levels in the serum and lungs. Moreover, the aged mice exhibited smaller tumors and reduced numbers of tumor foci in the lungs after challenge with intravenous injection of B16/F10 melanoma cells compared with the young mice. Aged lung Vγ4+ and Vγ6+ γδT cells were highly cytotoxic to B16/F10 melanoma cells with higher expression levels of CD103. The markedly longer survival of the challenged aged mice was dependent on γδT17 cells, since neutralization of IL‐17A or depletion of indicated γδT cells significantly shortened the survival time. Consistently, supplementation of IL‐17A significantly enhanced the survival time of young mice with lung melanoma. Furthermore, the anti‐tumor activity of aged lung γδT17 cells was not affected by alterations in the load and composition of commensal microbiota, as demonstrated through co‐housing of the aged and young mice. Intrinsically altered lung γδT17 cells underlying age‐dependent changes control lung melanoma, which will help to better understand the lung cancer progression in the elderly and the potential use of γδT17 cells in anti‐tumor immunotherapy. 相似文献
44.
目的探讨轻度支气管哮喘儿童的诱导痰菌群特征及临床意义。方法纳入年龄为6~12周岁于2018年11月至2019年1月在深圳市儿童医院呼吸科门诊定期复诊的轻度支气管哮喘患儿51例(哮喘组),留取诱导痰,匹配同年龄段97例健康无过敏儿童的口咽拭子作为对照。诱导痰及口咽拭子提取总DNA并扩增,对16S rRNA基因进行高通量测序并对测序结果进行生物信息学分析。结果NMDS分析结果显示哮喘组与健康对照组研究对象菌群结构存在差异;哮喘组的诱导痰菌群多样性指数(Shannon index)高于健康对照组(2.34±0.53 vs 1.87±0.50,P<0.05)。门水平分析显示,哮喘组与健康对照组的菌群均主要为厚壁菌门(38.34%vs 44.74%,P<0.05)、变形杆菌门(31.14%vs 19.78%,P<0.05)、拟杆菌门(14.59%vs 20.52%,P<0.05)、放线菌门(10.41%vs 7.85%,P<0.05)和梭杆菌门(2.82%vs 6.67%,P<0.05),但两组之间的构成比有明显差异。与健康对照组相比,在属水平上哮喘组韦荣球菌属(5.27%vs 8.96%)、普雷沃菌属(8.38%vs 17.35%)、罗斯菌属(1.50%vs 5.46%)、纤毛菌属(1.37%vs 4.39%)等非条件致病菌属比例明显下降(均P<0.05),而嗜血杆菌属(9.83%vs 6.17%)、卟啉单胞菌属(2.48%vs 1.41%)、莫拉菌属(5.66%vs 0.42%)、诺卡菌属(3.40%vs 0.00%)等条件致病菌属比例明显上升(均P<0.05)。结论尽管轻度支气管哮喘患儿已临床控制,但诱导痰内菌群仍存在结构紊乱。气道菌群紊乱可能是儿童支气管哮喘的发病机制之一。除了致病菌属外,非致病菌菌属的构成变化可能也是儿童哮喘的一个发生机制。 相似文献
45.
Molecular and Cellular Biochemistry - Ginseng is an ancient perennial herb belonging to the family Araliaceae and genus Panax which has been used for medical therapeutics for thousands of years,... 相似文献
46.
Andr Gomes-dos-Santos Manuel Lopes-Lima Andr M Machado Antnio Marcos Ramos Ana Usi Ivan N Bolotov Ilya V Vikhrev Sophie Breton L Filipe C Castro Rute R da Fonseca Juergen Geist Martin E
sterling Vincent Pri Amílcar Teixeira Han Ming Gan Oleg Simakov Elsa Froufe 《DNA research》2021,28(2)
Since historical times, the inherent human fascination with pearls turned the freshwater pearl mussel Margaritifera margaritifera (Linnaeus, 1758) into a highly valuable cultural and economic resource. Although pearl harvesting in M. margaritifera is nowadays residual, other human threats have aggravated the species conservation status, especially in Europe. This mussel presents a myriad of rare biological features, e.g. high longevity coupled with low senescence and Doubly Uniparental Inheritance of mitochondrial DNA, for which the underlying molecular mechanisms are poorly known. Here, the first draft genome assembly of M. margaritifera was produced using a combination of Illumina Paired-end and Mate-pair approaches. The genome assembly was 2.4 Gb long, possessing 105,185 scaffolds and a scaffold N50 length of 288,726 bp. The ab initio gene prediction allowed the identification of 35,119 protein-coding genes. This genome represents an essential resource for studying this species’ unique biological and evolutionary features and ultimately will help to develop new tools to promote its conservation. 相似文献
47.
Jun Zuo Lili Hu Wei Shen Jiaying Zeng Lin Li Lirong Song Nanqin Gan 《Environmental microbiology》2021,23(2):1066-1078
Lake Taihu in China has suffered serious harmful cyanobacterial blooms for decades. The algal blooms threaten the ecological sustainability, drinking water safety, and human health. Although the roles of abiotic factors (such as water temperature and nutrient loading) in promoting Microcystis blooms have been well studied, the importance of biotic factors (e.g. bacterial community) in promoting and meditating Microcystis blooms remains unclear. In this study, we investigated the ecological dynamics of bacterial community, the ratio of toxic Microcystis, as well as microcystin in Lake Taihu. High-throughput 16S rRNA sequencing and principal component analysis (PCA) revealed that the bacteria community compositions (BCCs) clustered into three groups, the partitioning of which corresponded to that of groups according to the toxic profiles (the ratio of toxic Microcystis to total Microcystis, and the microcystin concentrations) of the samples. Further Spearman's correlation network showed that the α-proteobacteria Phenylobacterium strongly positively correlated with the toxic profiles. Subsequent laboratory chemostats experiments demonstrated that three Phenylobacterium strains promoted the dominance of the toxic Microcystis aeruginosa PCC7806 when co-culturing with the non-toxic PCC7806 mcyB− mutant. Taken together, our data suggested that the α-proteobacteria Phenylobacterium may play a vital role in the maintenance of toxic Microcystis dominance in Lake Taihu. 相似文献
48.
Jibing Li Chunling Luo Dayi Zhang Xuan Zhao Yeliang Dai Xixi Cai Gan Zhang 《Environmental microbiology》2021,23(11):7042-7055
Rhizoremediation is a potential technique for polycyclic aromatic hydrocarbon (PAH) remediation; however, the catabolic pathways of in situ rhizosphere PAH degraders and the main factors driving PAH rhizoremediation remain unclear. To address these issues, stable-isotope-probing coupled with metagenomics and molecular ecological network analyses were first used to investigate the phenanthrene rhizoremediation by three different prairie grasses in this study. All rhizospheres exhibited a significant increase in phenanthrene removal and markedly modified the diversity of phenanthrene degraders by increasing their populations and interactions with other microbes. Of all the active phenanthrene degraders, Marinobacter and Enterobacteriaceae dominated in the bare and switchgrass rhizosphere respectively; Achromobacter was markedly enriched in ryegrass and tall fescue rhizospheres. Metagenomes of 13C-DNA illustrated several complete pathways of phenanthrene degradation for each rhizosphere, which clearly explained their unique rhizoremediation mechanisms. Additionally, propanoate and inositol phosphate of carbohydrates were identified as the dominant factors that drove PAH rhizoremediation by strengthening the ecological networks of soil microbial communities. This was verified by the results of rhizospheric and non-rhizospheric treatments supplemented with these two substances, further confirming their key roles in PAH removal and in situ PAH rhizoremediation. Our study offers novel insights into the mechanisms of in situ rhizoremediation at PAH-contaminated sites. 相似文献
49.
Yu Gan Tianzhu Zhang Sai Liang Zhongnan Zhao Nan Li 《Journal of Industrial Ecology》2013,17(3):440-451
Resource productivity enhancement stands at the center of tackling issues on environmental pollution and resource scarcity. Identifying influential socioeconomic factors should be the first step in establishing and improving resource management policy. This study compares and analyzes data from multiple countries to construct a resource productivity simulation model. The socioeconomic factors and their characteristic patterns are discussed in detail. The results demonstrate that the major factors influencing resource productivity include income level, population density, economic structure, energy structure, and raw material trade. Among these factors, the three most important are income level, population density, and economic structure. The influencing patterns can be summarized as follows: (1) Resource productivity increases with increasing income levels. (2) Countries with high population density are inclined to demonstrate high resource productivity. (3) The economic structure shows a biphase influence on resource productivity, that is, during industrialization, decreased agricultural activity and increased industrial activity lead to higher resource productivity. On the other hand, after industrialization, decreasing industrial activity and an expanding service sector become the major impetus of resource productivity enhancement. (4) Raw material export demonstrates a negative effect on resource productivity. Countries that depend heavily on raw material export show a unique resource productivity evolution pattern. For these countries, relatively high resource productivity in low income phases and relatively low resource productivity in high income phases show only small increases in resource efficiency and economic growth. Finally, insights from the study are transformed into suggestions for sustainable resource management and resource productivity enhancement. 相似文献
50.
Longzhan Gan Shuai Zhang Yi Zhang Shuang He 《Preparative biochemistry & biotechnology》2013,43(7):582-588
AbstractWe have conducted a thorough study on extracellular biosynthesis of silver nanoparticles (AgNPs) by a halotolerant bacterium Bacillus endophyticus SCU-L, which was identified by 16S rRNA gene sequencing analysis. This strain was selected during an ongoing research programme aimed at finding a novel biological method for green nanosynthetic routes using the extremophiles in unexplored hypersaline habitats. The biosynthesized AgNPs were characterized and analyzed with UV–vis spectroscopy, Fourier transform infrared spectroscopy, transmission electron microscopy, atomic force microscopy and X-ray diffraction. Further, the AgNPs were found to be spherical in shape with an average particle size of about 5.1?nm, and it was stable in aqueous solution for three months period of storage at room temperature under dark condition. Also, the synthesized AgNPs significantly presented antimicrobial activity against Candida albicans, Escherichia coli, Salmonella typhi and Staphylococcus aureus. The above results suggested that the present work may provide a valuable reference and theoretical basis for further exploration on microbial biosynthesis of AgNPs by halotolerant bacteria. 相似文献