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991.
Effects of resuspension and eutrophication level on summer phytoplankton dynamics in two hypertrophic areas of Lake Taihu,China 总被引:1,自引:0,他引:1
The composition of summer phytoplankton communities in two highly eutrophic areas of Lake Taihu, a large, shallow water body
in China (area 2,338 km2; mean depth 2.0 m), was studied in relation to selected environmental variables. Both areas have multiple uses, including
drinking water supply, fisheries, and recreation. The first area, Meiliang Bay, is much closer to central lake and subjected
to wind-driven sediment resuspension, while the second, at Wuli Lake, is less affected by wave action but is considered more
nutrient-rich due to its proximity to human inhabitation. By comparing two lake areas, we attempt to advance the understanding
and management of different regions of shallow lakes, mainly differing in resuspension levels and eutrophication levels. A
comparison of these two lake areas indicated a higher standing crop of phytoplankton in Wuli Lake than in Meiliang Bay. Canonic
Correspondence Analysis indicated that nutrient status and sediment resuspension were the principal factors influencing phytoplankton
composition in both areas. The dominant algal group in Meiliang Bay comprised immobile R-type strategists (Reynolds in Growth and reproductive strategies of freshwater phytoplankton, 1988), including filamentous diatoms and green algae (Aulacoseira granulate and Planctonema lauterbornii), and recruitment-beneficial RS-type strategists, mainly the colonial cyanobacteria (Microcystis spp.). The community of Wuli Lake was dominated by S-strategists, principally motile flagellates (Cryptomonas spp.) and C-strategists including small nonmotile centric diatoms and chlorococcal green algae. 相似文献
992.
In plants, reactive oxygen species (ROS) are short-lived molecules produced through various cellular mechanisms in response
to biotic and abiotic stimuli. ROS function as second messengers for hormone signaling, development, oxygen deprivation, programmed
cell death, and plant–pathogen interactions. Recent research on ROS-mediated responses has produced stimulating findings such
as the specific sources of ROS production, molecular elements that work in ROS-mediated signaling and homeostasis, and a ROS-regulated
gene network (Neill et al., Curr Opin Plant Biol 5:388–395, 2002a; Apel and Hirt, Annu Rev Plant Biol 55:373–399, 2004; Mittler et al., Trends Plant Sci 9:490–498, 2004; Mori and Schroeder, Plant Physiol 135:702–708, 2004; Kwak et al., Plant Physiol 141:323–329, 2006; Torres et al., Plant Physiol 141:373–378, 2006; Miller et al., Physiol Plant 133:481–489, 2008). In this review, we highlight new discoveries in ROS-mediated abscisic acid (ABA) signaling.
Drs. Daeshik Cho and June M. Kwak are the corresponding authors for this paper. 相似文献
993.
Jingcheng Wu Wenyi Zhao Binbin Zhou Zhixi Su Xun Gu Zhan Zhou Shuqing Chen 《基因组蛋白质组与生物信息学报(英文版)》2018,16(4):276-282
Tumor-specific neoantigens have attracted much attention since they can be used as biomarkers to predict therapeutic effects of immune checkpoint blockade therapy and as potential targets for cancer immunotherapy. In this study, we developed a comprehensive tumor-specific neoantigen database (TSNAdb v1.0), based on pan-cancer immunogenomic analyses of somatic mutation data and human leukocyte antigen (HLA) allele information for 16 tumor types with 7748 tumor samples from The Cancer Genome Atlas (TCGA) and The Cancer Immunome Atlas (TCIA). We predicted binding affinities between mutant/wild-type peptides and HLA class I molecules by NetMHCpan v2.8/v4.0, and presented detailed information of 3,707,562/1,146,961 potential neoantigens generated by somatic mutations of all tumor samples. Moreover, we employed recurrent mutations in combination with highly frequent HLA alleles to predict potential shared neoantigens across tumor patients, which would facilitate the discovery of putative targets for neoantigen-based cancer immunotherapy. TSNAdb is freely available at http://biopharm.zju.edu.cn/tsnadb. 相似文献
994.
湖北省三品种猪27个微卫星座位的遗传变异 总被引:41,自引:2,他引:41
采用国际动物遗传学会(ISAG)和联合国粮农组织(FAO)共同推荐的27个微卫星标记,对湖北省3个主要地方猪种(通城猪、清平猪和阳新猪)的遗传变异进行了检测。计算出各个品种的基因杂合度、各个座位的多态信息含量及品种间的遗传距离。结果表明,3个地方猪种的平均基因杂合度分别为0.7489、0.6987和0.6273,遗传多样性比较丰富;通城猪和清平猪亲缘关系较近,而两者与阳新猪亲缘关系略远。 相似文献
995.
Transgenic fish. 总被引:3,自引:0,他引:3
A range of transgenic animal species have been generated using DNA microinjection, and application of this technique to fish is now showing some degree of success. Studies to optimize microinjection techniques specifically for use with fish, and to investigate possible alternative methods for mass culture, should lead to the commercial production of transgenic fish able to transmit desirable characteristics, such as enhanced growth or disease resistance, to their progeny. 相似文献
996.
Site-directed mutagenesis (SDM) has been widely used for studying the structure and function of proteins. A one-step polymerase chain reaction (PCR)-based multiple site-directed plasmid mutagenesis method with extended non-overlapping sequence at the 3′ end of the primer increases the PCR amplification efficiency and the capacity of multi-site mutagenesis. Here, we introduced silent restriction sites in the primers used in this PCR-based SDM method by utilizing SDM-Assist software to generate mutants of Helicobacter pylori neutrophil-activating protein (HP-NAP), whose gene has low GC content. The HP-NAP mutants were efficiently generated by this modified mutagenesis method and quickly identified by a simple restriction digest due to the presence of the silent restriction site. This modified PCR-based SDM method with the introduction of a silent restriction site on the primer is efficient for generation and identification of mutations in the gene of interest. 相似文献
997.
裂解性复制诱导产生可视化重组Epstein Barr病毒 总被引:1,自引:0,他引:1
为了在病毒的整个基因组中研究基因的功能,分析基因与基因之间的相互作用,含有整个野生型EB病毒(EBV)基因组的BAC-EBV质粒(p2089),首先被转染EBV阴性的HEK293细胞,经潮霉素筛选建立了HEK293/p2089稳定细胞系.再构建pcDNA3.1( )/BZLF1和pcDNA3.1( )/BALF4真核表达质粒,共转染至HEK293/p2089细胞内,诱导EBV裂解性复制产生可视化的重组EBV颗粒.重组EBV颗粒感染Raji细胞,在倒置荧光显微镜下和流式细胞仪记数GFP阳性细胞,根据这些"绿色Raji单位"确定病毒的滴度.在国内首次建立这种以细菌人工染色体(BAC)为基础的EBV感染性克隆技术,将允许对EB病毒基因组中任何基因的任何遗传修饰,为在整个基因组中对EB病毒基因功能的研究奠定了基础,也为对EBV与其相关的肿瘤如鼻咽癌发生机理的研究建立了新的技术平台. 相似文献
998.
Lei Wang Kunzheng Cai Yuting Chen Guoping Wang 《Biological trace element research》2013,152(2):275-283
Bacterial wilt caused by Ralstonia solanacearum is a serious soil-borne disease of Solanaceae crops. In this study, the soil microbial effects of silicon-induced tomato resistance against R. solanacearum were investigated through pot experiment. The results showed that exogenous 2.0 mM Si treatment reduced the disease index of bacterial wilt by 19.18 % to 52.7 % compared with non-Si-treated plants. The uptake of Si was significantly increased in the Si-treated tomato plants, where the Si content was higher in the roots than that in the shoots. R. solanacearum inoculation resulted in a significant increase of soil urease activity and reduction of soil sucrase activity, but had no effects on soil acid phosphatase activity. Si supply significantly increased soil urease and soil acid phosphatase activity under pathogen-inoculated conditions. Compared with the non-inoculated treatment, R. solanacearum infection significantly reduced the amount of soil bacteria and actinomycetes by 52.5 % and 16.5 %, respectively, but increased the ratio of soil fungi/soil bacteria by 93.6 %. After R. solanacearum inoculation, Si amendments significantly increased the amount of soil bacteria and actinomycetes and reduced soil fungi/soil bacteria ratio by 53.6 %. The results suggested that Si amendment is an effective approach to control R. solanacearum. Moreover, Si-mediated resistance in tomato against R. solanacearum is associated with the changes of soil microorganism amount and soil enzyme activity. 相似文献
999.
Weizhen Li Songwen Chen Genqing Zhou Hongli Li Lan Zhong Shaowen Liu 《Saudi Journal of Biological Sciences》2018,25(3):500-506
The present study aimed to evaluate the importance of cyanidin 3-glucoside (C3G) of diabetic cardiomyopathy in diabetic rats. The rats were induced with diabetic using streptozotocin and total triglyceride (TG) and total cholesterol (TC) were determined. The range of myocardial enzymes such as aspartate aminotransferase (AST), creatine kinase (CK) and lactate dehydrogenase (LD) were also estimated, further, the Immuno histochemical analysis and western blot investigation were determined for the actual activity of C3G. Results indicated that the marker enzymes such as CK, LD and AST were significantly (P < 0.05) increased in STZ administered rats (DM group), while the levels of these elevated marker enzymes of cardiac injury significantly (P < 0.05) declined in the DM + C3G group, as compared to the diabetic group of rats. Additionally, a decrease in the level of TNF-alpha and interleukin-6, was noticed in the C3G treated group as compared to diabetic group. Finally, blotting analysis clearly confirmed that theC3G treatment resulted to higher level response of Bcl-2 and lower level response of caspase-3 and BAX. In conclusion, C3G a natural antioxidant may prevent cardiovascular complications by ameliorating oxidative damage, inflammation, metabolic dysfunctions and apoptosis pathways in type 2 diabetes. 相似文献
1000.
籼粳亚种间杂交稻米脂肪含量的遗传分析 总被引:4,自引:0,他引:4
用包括基因型×环境互作效应的种子性状遗传模型,研究了籼粳亚种间杂交稻米脂肪含量的遗传特性,结果表明:在籼粳杂种中,脂肪含量的遗传表达主要受控于种子直接加性效应和母体加性效应,以前者为主.基因型X环境互作主要表现为显性(包括直接显性和母体显性)X环境以及细胞质X环境工作.直接近传率和母体遗传率都极显著.此外,根据遗传效应预测值对供试条本的利用价值作了评价. 相似文献