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101.
为增加对刀鲚在进化过程中因核心基因家族改变而产生的特殊机制的了解。实验利用比较基因组学,通过比较刀鲚及其近缘物种斑马鱼、三刺鱼、青鳉、红鳍东方鲀和绿河鲀基因组,鉴定刀鲚基因家族;利用CAFév 4.2软件进行基因家族扩张和收缩分析;最后将鉴定的扩张基因家族基因与GO、KEGG等数据库进行比对、注释和通路分析。结果显示,刀鲚具有11 872个基因家族,包含16 470个基因,有2 963个基因未形成基因家族。同其他5个物种相比,刀鲚有150个特有基因家族,包含419个基因。刀鲚扩张和收缩基因家族分析结果表明,刀鲚有1 200个基因家族扩张了,7 543个基因家族收缩了。刀鲚显著扩张的基因家族有39个,包含508个基因;显著收缩的基因家族有36个,包含21个基因。刀鲚显著扩张基因家族GO富集分析条目中鉴定较多的是,代谢过程、催化活性、细胞、细胞组分等。KEGG富集分析条目中鉴定较多的是紧密连接、心肌细胞的肾上腺素能信号、心肌收缩、细胞黏附分子等。与渗透压调节相关的通路有紧密连接、心肌收缩等;与生殖洄游行为相关的通路有GnRH信号通路、嗅觉转导通路等。对显著扩张基因家族基因进行基因组定位,结... 相似文献
102.
Jin Ju Lee Jae Hong Kim Dae Geun Kim Dong Hyeok Kim Hannah Leah Simborio Won Gi Min Man Hee Rhee Jong Hwan Lim Hong Hee Chang Suk Kim 《Veterinary microbiology》2014
The pathogenic mechanisms of Brucellosis used to adapt to the harsh intracellular environment of the host cell are not fully understood. The present study investigated the in vitro and in vivo characteristics of B. abortus betaine aldehyde dehydrogenase (BetB) (Gene Bank ID: 006932) using a betB deletion mutant constructed from virulent B. abortus 544. In test under stress conditions, including osmotic- and acid stress-resistance, the betB mutant had a lower osmotic-resistance than B. abortus wild-type. In addition, the betB mutant showed higher internalization rates compared to the wild-type strain; however, it also displayed replication failures in HeLa cells and RAW 264.7 macrophages. During internalization, compared to the wild-type strain, the betB mutant was more adherent to the host surface and showed enhanced phosphorylation of protein kinases, two processes that promote phagocytic activity, in host cells. During intracellular trafficking, colocalization of B. abortus-containing phagosomes with LAMP-1 was elevated in betB mutant-infected cells compared to the wild-type cells. In mice, the betB mutant was predominantly cleared from spleens compared to the wild-type strain after 2 weeks post-infection, and the vaccination test with the live betB mutant showed effective protection against challenge infection with the virulent wild-type strain. These findings suggested that the B. abortus betB gene substantially affects the phagocytic pathway in human phagocytes and in host cells in mice. Furthermore, this study highlights the potential use of the B. abortus betB mutant as a live vaccine for the control of brucellosis. 相似文献
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ZHUANG Xiang-hua NI Yi-hong LIU Yuan-tao SUN Ai-li SUN Fu-dun JIANG Dong-qing LI Xiao-bo CHEN Shi-hong 《园艺学报》2014,30(11):2084-2088
AIM: To establish a suitable chronic intermittent hypoxia (CIH) model in rats for modeling the obstructive sleep apnea-hypopnea syndrome (OSAHS) and further to explore the relationship between vaspin and insulin signaling pathways at mRNA and protein levels. METHODS: Healthy male Wistar rats were divided into control group and CIH group. The rats in control group were raised under physiological condition, and the rats in CIH group were kept in the plexiglass chamber between 9:00~17:00 and underwent intermittent hypoxic challenge 8 h/d for 8 weeks. The blood pressure of arteria caudilis in the rats was measured by tail cannulation before and after study. Fasting plasma glucose (FPG), total cholesterol (TC), triglycerides (TG), fasting insulin (FINS), vaspin and adiponectin levels were measured. The mRNA expression of vaspin was detected by real-time PCR. The protein levels of vaspin, Akt and p-Akt were determined by Western blotting.RESULTS: Before the experiment, the weight and blood pressure of the rats had no significant difference, while after the experiment the blood pressure in CIH group was obviously higher than that in control group. FPG, FINS, TG and TC in CIH group were also markedly higher than those in control group (P<0.05). Serum vaspin concentration was significantly correlated with FPG, FINS, HOMA-IR and TC. The expression of vaspin at mRNA and protein levels in the fat tissue of CIH group was evidently higher than that in control group. The protein levels of p-Akt decreased distinctly in CIH group. CONCLUSION: The levels of FINS, HOMA-IR, SaO2 and vaspin were markedly higher than those in control group, indicating that there was a close relationship between vaspin and insulin resistance in OSAHS. 相似文献
106.
AIM:To investigate the relationship of microRNA-7 (miRNA-7) over-expression and epidermal growth factor receptor (EGFR)/phosphatidylinositol kinase-3 (PI3K)/protein kinase B (PKB, also called Akt) pathway in human nasopharyngeal carcinoma 5-8F cells. METHODS:The 5-8F cells were transfected with miRNA-7 mimics (carrying by Lipofectamine 2000). The expression of miRNA-7 was detected by real-time PCR. The cell proliferation was analyzed by CCK-8 assay. The cell colony-forming capability was determined by cell colony formation test. The expression of EGFR/PI3K/Akt at mRNA and protein levels was examined by real-time PCR and Western blotting. RESULTS:The expression level of miRNA-7 was significantly increased in 5-8F cells compared with negative control (NC) group and control group (P<0.01). The proliferation of NPC 5-8F cells was decreased extremely after tansfected with the miRNA-7 mimics (P<0.01), so did the result of the cell colony-formation test. The expression of EGFR/PI3K/Akt at mRNA and protein levels was significantly down-regulated compared with NC group and control group (P<0.01). CONCLUSION: Over-expression of miRNA-7 significantly inhibits the proliferation and colony-forming ability of nasopharyngeal carcinoma 5-8F cells by down-regulation of EGFR/PI3K/Akt pathway. 相似文献
107.
AIM:To investigate the inhibitory effects of resveratrol on chondrosarcoma and the relation with mitochondrial and PI3K/Akt pathways. METHODS:Chondrosarcoma SW1353 cells were treated with resveratrol at concentrations of 25, 50 and 100 μmol/L for the time intervals of 24 h, 48 h and 72 h. The viability and apoptosis of the SW1353 cells in the presence or absence of resveratrol were analyzed by CCK8 assay and Hoechst 33258 staining, respectively. The protein levels of Bcl-2, Bax, activated caspase-3, Akt and p-Akt were detected by Western blotting. The cell migration ability was determined by wound scratch assay. RESULTS:Exposure of the cells to resveratrol resulted in a decrease in the cell viability in a dose- and time-dependent manner (P<0.05). visible nuclei with apoptotic characteristics in resveratrol group were observed. The protein levels of activated caspase-3 and Bax were increased, and Bcl-2 and p-Akt were decreased compared with control group. The total Akt were not significantly changed. Resveratrol also significantly reduced the migration of tumor cells. CONCLUSION:Resveratrol induces apoptosis of chondrosarcoma, which plays a role of part through mitochondrial and PI3K/Akt signaling pathways. 相似文献
108.
AIM:To investigate the changes of Wnt signaling pathway in catalpol-induced proliferation of rat bone marrow mesenchymal stem cells (BMSCs). METHODS:The BMSCs were isolated from SD rats, purified by differential time adherent method and divided into control group and catalpol (1.0 mg/L) group. Flow cytometry was used to detect the proliferation index of BMSCs. The mRNA levels of Wnt3a, Wnt5a, Wnt11 and β-catenin was evaluated by real-time PCR. In addition, the protein expression level of β-catenin was determined by Western blotting. RESULTS:Prolife-ration index was increased from 8.90%±0.46% to 17.93%±1.68% after treatment with catalpol (P<0.01). Compared with control group, the mRNA expression of Wnt5a, Wnt11 and β-catenin was all increased with catalpol treatment. No difference of Wnt3a mRNA expression between control group and catalpol group was observed. Meanwhile, the protein expression of β-catenin was increased in catalpol group compared with control group. CONCLUSION:Catalpol promotes BMSCs going into the cell cycle. Classical and non-classical Wnt signaling pathways are activated in this process. 相似文献
109.
通过本地查找胶孢炭疽病菌(Colletotrichum gloeosporioides)橡胶菌株全基因组测序数据,获得PalF基因的序列信息。利用同源克隆的方法扩增胶孢炭疽病菌芒果菌株PalF基因,获得片段大小为2 369 bp的目的基因片段。对该基因序列进行分析发现,该片段含有完整的开放式阅读框,与橡胶炭疽菌PalF基因的序列同源性达100%。用RT-PCR的方法获得PalF基因的cDNA序列,序列进行分析发现该基因全长为2 310 bp,其中含有1个大小为59 bp的内含子,推测编码769个氨基酸。对PalF基因的氨基酸序列进行推测保守结构域分析可知PalF蛋白中含有Arrestin-C保守结构域,推测该基因参与环境pH感应信号转导途径(Ambient pH-sensing signal transduetion pathway)的调控,为进一步研究该基因在环境pH感应信号转导途径中的作用奠定了基础。 相似文献
110.