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51.
Using a proteomic approach, we have previously shown that exposure to different concentrations of cisplatin during a 12-h period can lead to changes in nuclear protein expression and alternative splicing in HeLa cells. To further shed light on the DNA damage response (DDR) induced by cisplatin, we examined the nuclear proteome profiles of HeLa cells treated with 5μM cisplatin for different times (2, 12, and 24h). Two-dimensional electrophoresis (2-DE) identified 98 differentially expressed proteins in cisplatin-treated cells as compared to control cells. Among them, 54 spots (55%) were down-regulated and 44 spots (45%) were up-regulated. 51 spots were subjected to Matrix-assisted-laser-desorption-ionization Time-of-flight/time-of-flight Mass spectrometry (MALDI-TOF/TOF MS) identification, and 40 spots were identified. Among these, 22 proteins were located in nucleus. These proteins were involved in stress response, cell cycle and division, apoptosis, mRNA processing, transport, splicing and microRNA (miRNA) maturation. The changed expression of Annexin A1 and Lamin B1 were confirmed by Western blot. The role of Annexin A1 in the response to cisplatin-induced DNA damage was further analyzed, and it was shown that after Annexin A1 knockdown, cisplatin-induced DNA damage was significantly increased. In addition, the changed expression of several miRNAs was also observed by quantitative real-time PCR (qRT-PCR). Taken together, these data indicate that cisplatin-induced DDR is a complex process, and that those proteins identified by proteomics can lead to new directions for a better understanding of this process.  相似文献   
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53.
Colorectal cancer (CRC) is one of the most common tumors worldwide and is associated with high mortality. Here we performed bioinformatics analysis, which we validated using immunohistochemistry in order to search for hub genes that might serve as biomarkers or therapeutic targets in CRC. Based on data from The Cancer Genome Atlas (TCGA), we identified 4832 genes differentially expressed between CRC and normal samples (1562 up-regulated and 3270 down-regulated in CRC). Gene ontology (GO) analysis showed that up-regulated genes were enriched mainly in organelle fission, cell cycle regulation, and DNA replication; down-regulated genes were enriched primarily in the regulation of ion transmembrane transport and ion homeostasis. Weighted gene co-expression network analysis (WGCNA) identified eight gene modules that were associated with clinical characteristics of CRC patients, including brown and blue modules that were associated with cancer onset. Analysis of the latter two hub modules revealed the following six hub genes: adhesion G protein-coupled receptor B3 (BAI3, also known as ADGRB3), cyclin F (CCNF), cytoskeleton-associated protein 2 like (CKAP2L), diaphanous-related formin 3 (DIAPH3), oxysterol binding protein-like 3 (OSBPL3), and RERG-like protein (RERGL). Expression levels of these hub genes were associated with prognosis, based on Kaplan–Meier survival analysis of data from the Gene Expression Profiling Interactive Analysis database. Immunohistochemistry of CRC tumor tissues confirmed that OSBPL3 is up-regulated in CRC. Our findings suggest that CCNF, DIAPH3, OSBPL3, and RERGL may be useful as therapeutic targets against CRC. BAI3 and CKAP2L may be novel biomarkers of the disease.  相似文献   
54.
刘军  斯信强 《人类学学报》1997,16(3):231-238
本文记述盘县大洞近期历史中沿革和对洞内已出露的堆积层初步观察的结果,大洞堆积层近斯的人为破坏十分严重,但中下部基本上完好,组成物质和结构表明,整个堆积层是在大洞脱离地下河的环境之后形成的,而根据所含的动物化石,人类化石,文化遗物的性质,以及钟乳石的铀系年龄,中上部堆积属中更新世晚期。  相似文献   
55.
Liang Z  Han Z  Yang S  Liang X  Du P  Liu G  Yang Y 《Bioresource technology》2011,102(2):710-715
To achieve an appropriate mixture of ammonium and nitrite for anaerobic ammonium oxidation (ANAMMOX), 50% partial nitritation was optimized in a fixed bed biofilm reactor treating synthetic wastewater. Results suggested that 50% partial nitritation could be achieved by stepwise increases of influent NH4+-N at pH of 7.8 ± 0.2, temperature of 30 ± 1 °C and dissolved oxygen (DO) of 0.5-0.8 mg l−1. Hydraulic retention time (HRT) and influent alkalinity did significantly affect partial nitritation. At HRT 12 h, 50% partial nitritation could be kept stable, regardless of influent NH4+-N variation, by controlling the influent HCO3/NH4+ molar ratio at 1:1. The fluorescent in situ hybridization (FISH) results indicated the abundance of evolution of ammonia-oxidizing bacteria (AOB) and the nitrite-oxidizing bacteria (NOB) coincided well with the performance of partial nitritation. Furthermore, the AOB were highly affiliated with Nitrosomonas spp. and Nitrosospira spp. dominated (64.1%) in the biofilm with a compact structure during the stable 50% partial nitritation period.  相似文献   
56.
Thirty-one N(4)-mono alkyl derivatives of novel glycopeptide LYV07ww01 were synthesized by the reductive alkylation and their in vitro antibacterial activity was tested. The benzyl derivatives showed potent activity, especially against vancomycin-resistant enterococci and penicillin-resistant Streptococcus pneumoniae.  相似文献   
57.
本研究旨在通过16SrDNA基因高通量测序技术探究青贮饲用高粱对30头肉牛瘤胃液细菌区系组成的影响.选择发育水平相近、膘体基本一致的西门塔尔与安格斯阉牛30头,随机分为10个组,每组3头.在实验最后一天晨饲后3 h,采用瘤胃口腔导管法采集瘤胃液样品,对其细菌区系进行高通量基因测序.结果表明:瘤胃液细菌区系中主要含有厚壁菌门(Firmicutes)、拟杆菌门(Bacteroidetes).其相对丰度分别为49.82%、42.83%,是试验牛瘤胃液的优势菌门.在瘤胃液细菌区系己知属水平分类中优势菌群为普雷沃菌属(Prevotella)及解琥珀酸菌属(Succiniclasticum).DMG组的细菌物种丰富度最高,普通精料组的细菌物种丰富度随着青贮饲料比例的变化而增大,生物精料的细菌物种丰富度随着青贮饲用高粱的比例的升高而降低.普通精料组日粮饲喂肉牛,对肉牛瘤胃液细菌物种丰富度及细菌群落多样性影响不显著.生物精料组日粮饲喂肉牛,显著增加了肉牛瘤胃液细菌物种丰富度及细菌群落多样性.  相似文献   
58.
探讨蛋白酶体抑制剂MG132 在诱导人白血病K562细胞凋亡过程中作用.分别以不同浓度的蛋白酶体抑制剂MG132 处理人白血病细胞K562,通过MTT法检测K562细胞活力,应用Annexin Ⅴ和PI 双染的细胞流式法检测K562细胞凋亡率和细胞内活性氧(ROS) 水平,应用酶标仪法检测K562细胞内Caspase- 3活性变化的情况.结果表明,随着MG132浓度的增加,各个指标与对照组比较差异均有显著性(P<0.05):K562细胞增殖明显受到抑制;细胞凋亡率明显增加,且当MG132浓度为900 nmol/L时,细胞凋亡率达36.5 %;同时,ROS 水平和caspase- 3活性明显升高.因次,蛋白酶体抑制剂MG132可显著抑制人白血病细胞K562增殖并促进其凋亡.  相似文献   
59.
Müller KJ  He X  Fischer R  Prüfer D 《Planta》2006,224(5):1023-1027
Seed plants with compound leaves constitute a polyphyletic group, but studies of diverse taxa show that genes of the class 1 KNOTTED-LIKE HOMEOBOX (KNOX1) family are often involved in compound leaf development. This suggests that knox1 genes have been recruited on multiple occasions during angiosperm evolution (Bharathan et al. in Science 296:1858–1860, 2002). In agreement with this, we demonstrate that the simple leaf of dandelion (Taraxacum officinale Web.) can be converted into a compound leaf by the constitutive expression of heterologous knox1 genes. Dandelion is a rosette plant of the family Asteraceae, characterised by simple leaves with deeply lobed margins and endogenous knox1 gene expression. Transgenic dandelion plants constitutively expressing the barley (Hordeum vulgare L.) hooded gene (bkn3, barley knox3) or the related bkn1 gene, developed compound leaves featuring epiphyllous rosettes. We discuss these results in the context of two current models of compound leaf formation.Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users.  相似文献   
60.
东海浮游植物数量分布与优势种   总被引:16,自引:0,他引:16  
罗民波  陆健健  王云龙  沈新强  晁敏 《生态学报》2007,27(12):5076-5085
根据1997~2000年东海23°30′~33°N、118°30′~128°E海域4个季节海洋调查资料,运用定量、定性方法,探讨了东海浮游植物总丰度的平面分布、季节分布及变化的动力学机制,同时还探讨了东海浮游植物优势种的生态学特征和对温盐环境适应特征。结果表明:东海浮游植物总丰度有明显的季节分布,秋季总丰度达到4季最高峰,均值为211.91×104cell.m-3,夏季次之(50.40×104cell.m-3),冬季11.34×104cell.m-3,春季(2.01×104cel.lm-3)最低。春夏季东海近海(Ⅰ和Ⅲ)高于外海(Ⅱ和Ⅳ),秋冬季东海北部外海(Ⅱ)高于近海(Ⅰ),南部近海(Ⅲ)高于外海(Ⅳ)。4季共出现优势种(Y≥0.02)11种,冬季的主要优势种为洛氏角毛藻和细弱海链藻,春季的主要优势种为洛氏角毛藻和夜光藻,夏季以拟弯角毛藻和细长翼根管藻为主要优势种,秋季优势种仅为聚生角毛藻。浮游植物的聚集强度指数为较大正值,聚集作用明显。从全年的逐步回归分析结果看,温度是影响浮游植物总丰度季节分布的主要因子,盐度是次要因子。浮游植物的11个优势种之间生存环境适应比较,洛氏角毛藻和中华盒形藻生长温度幅度较大,可以在12~28℃水温增长,因而春、夏和冬季都成为优势种。中肋骨条藻适合生长的水温范围都较小,仅为22~28℃。聚生角毛藻更小,仅21~25℃。洛氏角毛藻和中华盒形藻生长温盐度和高分布区温盐度范围比聚生角毛藻和中肋骨条藻都广,而秋季数量却低于聚生角毛藻。  相似文献   
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