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91.
The Escherichia coli proteome was digested with trypsin and fractionated using SPE on a C18 SPE column. Seven fractions were collected and analyzed by CZE‐ESI‐MS/MS. The separation was performed in a 60‐cm‐long linear polyacrylamide‐coated capillary with a 0.1% v/v formic acid separation buffer. An electrokinetic sheath‐flow electrospray interface was used to couple the separation capillary with an Orbitrap‐Velos operating in higher‐energy collisional dissociation mode. Each CZE‐ESI‐MS/MS run lasted 50 min and total MS time was 350 min. A total of 23 706 peptide spectra matches, 4902 peptide IDs, and 871 protein group IDs were generated using MASCOT with false discovery rate less than 1% on the peptide level. The total mass spectrometer analysis time was less than 6 h, the sample identification rate (145 proteins/h) was more than two times higher than previous studies of the E. coli proteome, and the amount of sample consumed (<1 μg) was roughly fourfold less than previous studies. These results demonstrate that CZE is a useful tool for the bottom‐up analysis of prokaryote proteomes.  相似文献   
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93.
Wu  Yuexia  Lian  Keqian  Sun  Cong 《Molecular and cellular biochemistry》2020,463(1-2):161-173
Molecular and Cellular Biochemistry - Alzheimer’s disease (AD) is the leading cause of dementia, which characterized by toxic senile plaques is composed of amyloid-β (Aβ)....  相似文献   
94.
Liu  Yuan  Luo  Cong  Zhang  Xiu-Juan  Lu  Xin-Xi  Yu  Hai-Xia  Xie  Xiao-Jie  Fan  Zhi-Yi  Mo  Xiao  He  Xin-Hua 《Plant Cell, Tissue and Organ Culture》2020,143(1):219-228
Plant Cell, Tissue and Organ Culture (PCTOC) - CONSTANS (CO)/CONSTANS-like (COL) genes play an important role in the photoperiodic flowering pathway. However, the functional roles of the CO/COL...  相似文献   
95.
Jia  Chunhua  Yu  Xiaojing  Zhang  Min  Liu  Zhiguang  Zou  Peng  Ma  Jun  Xu  Yachun 《Journal of Plant Growth Regulation》2020,39(2):631-640
Journal of Plant Growth Regulation - The growth and development of cold-season plants are susceptible to high temperature. Melatonin is a plant growth regulator with potential to improve plant...  相似文献   
96.
Long noncoding RNAs (lncRNAs) are found to be aberrantly expressed and pose significant impacts in colorectal cancer (CRC), the most prevalent type malignancy in the gastrointestinal tract. This study aimed to find out the regulation of lncRNA EIF3J antisense RNA 1 (EIF3J-AS1) on CRC progression. Expressions of EIF3J-AS1, microRNA-3163 (miR-3163), and Yes-associated protein 1 (YAP1) in tissues and cells were evaluated by real-time quantitative polymerase chain reaction (RT-qPCR) and Western blot analysis. Association of EIF3J-AS1 with CRC prognosis was analyzed through the online bioinformatics tool GEPIA. The biological function of EIF3J-AS1 in CRC was investigated by Cell Counting Kit-8, colony formation, caspase-3 activity, and TUNEL staining. Competitive endogenous RNA (ceRNA) network of EIF3J-AS1/miR-3163/YAP1 was determined by luciferase reporter and RNA immunoprecipitation assays. Results showed that EIF3J-AS1 was upregulated in CRC tissues and cell lines, indicating poor prognosis of CRC patients. The silence of EIF3J-AS1 led to reduced proliferation and facilitated apoptosis of CRC cells. Mechanistcally, EIF3J-AS1 was upregulated by cAMP-response element-binding protein-binding protein-mediated histone H3 on lysine 27 acetylation (H3K27ac) at the promoter region, and EIF3J-AS1 upregulated YAP1 expression through sponging miR-3163 in CRC cells. In conclusion, we first found that H3K27 acetylation-induced lncRNA EIF3J-AS1 improved proliferation and impeded apoptosis of colorectal cancer through the miR-3163/YAP1 axis, which might potentially provide a novel molecular-targeted strategy for CRC treatment.  相似文献   
97.
Tripartite motif containing 59 (TRIM59) functions as an oncoprotein in various human cancers including ovarian cancer. In this study, we found that TRIM59 gene amplification was prevalent in ovarian cancer tissues, and its amplification was significantly correlated with poorer overall survival. Moreover, knockdown of TRIM59 in SKOV3 and OVCAR3 cells, which had relatively high level of TRIM59, suppressed glucose uptake and lactate production. TRIM59 knockdown also decreased the expression of c-Myc and lactate dehydrogenase A, and the phosphorylation of extracellular signal-regulated kinase (ERK). TRIM59 overexpression in A2780 cells, which expressed low level of TRIM59, showed reverse effects. Notably, treatment with an ERK inhibitor (PD98059) completely abolished the oncogenic effects of TRIM59 overexpression. Interestingly, TRIM59 increased the ubiquitination of MAP kinase phosphatase 3 (MKP3), which may dephosphorylate and inactivate ERK. Ectopic expression of MKP3 inhibited the promoting effects of TRIM59 on glycolysis and the phosphorylation of ERK. TRIM59 protein expression was negatively correlated with MKP3 protein expression in ovarian cancer tissues. Finally, TRIM59 amplification potently affected the anticancer effect of 3-bromopyruvate, an inhibitor of glycolysis, in ovarian cancer cells and patient-derived xenograft. In conclusion, these results suggest that TRIM59 may regulate glycolysis in ovarian cancer via the MKP3/ERK pathway.  相似文献   
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99.
黑果枸杞不同组织内生细菌群落多样性   总被引:3,自引:1,他引:2  
【目的】黑果枸杞是我国荒漠区特有的药用盐生植物,本研究分析了黑果枸杞不同组织中内生细菌群落多样性特征及分布规律。【方法】应用Illumina MiSeq高通量测序技术对黑果枸杞内生细菌的16S rRNAV5-V7区域序列进行测定,并分析群落组成、多样性及功能等生物学信息。【结果】黑果枸杞不同组织内生细菌群落多样性及功能均有较大的差异。花、叶、果、茎和根产生的OTUs分别是182、173、119、187和254,群落多样性表现为根花果、茎叶。从门水平上看,变形菌门是优势菌门,在不同组织中均有分布,花、叶、果、茎和根中的相对丰度分别为87.66%、41.51%、81.76%、97.67%和61.85%。在属水平上显示内生细菌的分布表现出器官差异性。花部能够准确分类的优势菌属为沙雷氏菌属和不动杆菌属,相对丰度分别为11.57%和8.55%。叶部为红球菌属和慢生根瘤菌属,相对丰度分别为29.68%和5.53%。果实中为泛菌属、红球菌属和沙雷氏菌属,相对丰度分别为23.12%、5.52%和4.29%。茎部为沙雷氏菌属和假单胞菌属,相对丰度分别为12.03%和17.71%。根部为盐单胞菌属、Fodinicurvata和Lipingzhangella,相对丰度分别为24.18%、5.16%和4.86%。在不同组织中分布较广的盐单胞菌、沙雷氏菌、不动杆菌、红球菌、泛菌等菌属均具有较高耐盐性和促生、生防、降解有机污染物及抗氧化等功能。PICRUSt功能预测分析显示,黑果枸杞组织中内生细菌功能中涉及丰富的多糖、萜类和酮类、酶及维他命等次生代谢产物的生物合成。【结论】黑果枸杞内生细菌具有丰富的群落和功能多样性,拥有多种益生功能性状,也含有多个与人和植物体代谢相关的功能信息。不同组织优势菌属和功能信息各有不同,其中根部的内生细菌物种最丰富,花部和茎部参与各种代谢调控的细菌丰度最高。此外,不同组织中还含有大量未知种属的微生物类群,这些都为内生细菌功能利用和挖掘新的有益微生物资源提供广阔的发展空间。  相似文献   
100.
多酶组合催化制备L-高苯丙氨酸   总被引:1,自引:0,他引:1  
刘佳  宋伟  郭亮  陈修来  高聪  刘立明 《微生物学报》2021,61(9):2829-2842
【目的】L-高苯丙氨酸(L-HPA)是许多医药化学品的重要中间体,化学合成法生产L-HPA反应复杂、环境污染严重,本研究旨在开发高效环保的L-HPA酶法合成路线。【方法】采用模块化组装的方法,构建了一条以甘氨酸和苯乙醛为底物高产L-HPA的新途径。【结果】首先,根据文献挖掘设计了一条由苏氨酸醛缩酶(TA)、苏氨酸脱氨酶(TD)、苯丙氨酸脱氢酶(PheDH)和甲酸脱氢酶(FDH)组成的多酶组合催化途径,用于L-HPA的合成。其次,根据氨基基团的引入和重构,将L-HPA多酶组合催化途径分为基础单元和扩增单元,基础单元包括TA和TD,扩增单元包括PheDH和FDH。然后,利用不同表达水平的质粒,对基础单元和扩增单元进行蛋白表达的组合调节,获得最优工程菌BL21-C-M1-R-M2,使L-HPA产量达到208.6mg/L。最后,我们对全细胞转化体系进行优化,使L-HPA产量进一步提高到1226.6 mg/L,苯乙醛摩尔转化率为34.2%。【结论】该工艺路线绿色高效,为未来大规模生产L-HPA奠定基础。  相似文献   
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