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111.
112.
CC Cheng  N Lu  CL Peng  CC Chang  FD Mai  LY Chen  MH Liao  WM Wang  J Chang 《Proteomics》2012,12(15-16):2584-2597
The survivals of gastric cancer (GC) patients are associated with early diagnosis and effective treatments. Therefore, it is urgent for the discovery of early GC biomarkers and tumor-targeting therapeutics. The aim of this study was to uncover putative tissue biomarkers of GC using 2D DIGE and then apply one of these specific markers in GC treatment. We found three putative biomarkers of GC with significant differences in expression level compared to adjacent normal tissue, including glucose-regulated protein 78 (GRP78) and glutathione s-transferase pi (GSTpi) with increased expression level, and alpha-1 antitrypsin (A1AT) with reduced expression level. The overexpressed GRP78 was used as a targeted protein for guiding the drugs to tumor cells, leading to more effective treatment for GC xenografts. Our results demonstrated that the designated GRP78-binding peptide based on the sequence, WIFPWIQL, was selectively prone to recognize and bind to GC MKN45 cells in vitro, and also improve the delivery efficiency of polymeric micelles-encapsulated drugs into tumor cells and displayed better therapeutic outcome in experimental animals. This strategy of GRP78-mediated drug targeting system may bring chemotherapeutic drugs with more precise targeting to tumor cells, leading to minimize side effects on patients after chemotherapy.  相似文献   
113.
植物黄化病是一种常见的而且危害严重的病害.近年来,外来有害生物的入侵给我国造成了巨额经济损失,并且对我国农林业生产安全和生态环境造成了严重的威胁,对植物检疫工作提出了新挑战.对几种由植原体引起的植物黄化病的症状、病原分类及其检疫技术和综合防控措施进行综述.  相似文献   
114.
野生樱桃李扦插繁殖研究初报   总被引:1,自引:0,他引:1  
以野生樱桃李的新梢为试材,采用不同的扦插基质、不同浓度的吲哚丁酸(IBA)、萘乙酸(NAA)和生根粉(ABR)对野生樱桃李插条进行扦插生根试验.试验结果表明,野生樱桃李在蛭石与河沙中的生根效果好于锯末中的生根,蛭石与河沙中插条的生根率接近,生根率分别达到了40.0%、39.6%,因此都可作为野生樱桃李扦插的适宜基质.适宜浓度NAA、IBA可以促进野生樱桃李的生根,浓度过低,达不到促进效果,浓度过高,则可能抑制了插条的生根,相比而言,效果NAA较好,其适宜处理浓度为200 mg/L.但各种激素处理后,无论生根率高低,对根的生长具有促进作用.  相似文献   
115.
柑桔近缘植物酯酶同工酶的研究   总被引:2,自引:0,他引:2  
本文用聚丙烯酰胺凝胶电泳测定了柑桔近缘植物14个种群的种子及幼苗的酯酶同工酶,根据酶谱及扫描图的异同,分析了彼此的亲缘关系,试验结果表明,柑桔近缘植物种属间的酯酶同工酶的酶带数目,酶活性,迁移率及酶谱扫描均有不同程度的差异,同一品种不同发育时期的同工酶也具有不同表现形式,特别是柑桔种子的酯酶同工酶谱一般较稳定,可以作为柑桔亲缘关系的生化遗传指标。  相似文献   
116.
通过野外观察并采用杂交指数(OCI)测定、花粉/胚珠比(P/O)检测、人工控制授粉等方法,对长萼兰花蕉(Orchidantha chinensis var.longisepala(D.Fang) T.L.Wu)种群的繁育系统进行了研究,采用常规石蜡切片与扫描电子显微镜(SEM)观察了柱头与"V"形黏盘的结构与形态。结果表明,长萼兰花蕉单花花期一般为18 d,依其花部形态的变化可分为蕾期、花萼未反转期、花萼反转期、唇瓣枯萎期、花萼枯萎期5个时期;根据杂交指数值为4、P/O值为253.89 ±21.09、人工异花授粉结实率分别为45%(2014年)和75%(2015年),显示出长萼兰花蕉的繁育系统属于异交,且需要传粉者。石蜡切片观察到长萼兰花蕉黏盘区与柱头可授区之间是光滑的表皮细胞,结合人工授粉实验与分泌物含糖量测定结果表明,长萼兰花蕉的"V"形黏盘不具有可授性,其作用可能是分泌黏液附着在传粉者背部使其便于携带花粉。长萼兰花蕉整个花期环境湿冷、多雨且开花同步性较低,这些因素很可能造成其有效传粉媒介缺乏,影响了传粉成功;另一方面,长萼兰花蕉有性繁殖受到限制,其主要通过根状茎进行无性繁殖后代,所以分布范围比较狭窄。  相似文献   
117.
The picture depicts the different 3d‐printed organs, thorax, lungs, heart and bone. Assembled it is used as an optical phantom of a preterm infant for performing percutaneous optical measurements of the gas content in the lungs. In order to simulate the optical properties of the tissue, the heart and thorax can be filled with liquid phantoms, a mixture of Intralipid and Indian Ink. Further details can be found in the article by Jim Larsson et al. ( e201700097 ).

  相似文献   

118.
Although the toxicogenomics of kojic acid treated A375 human malignant melanoma cells has been elucidated, the proteomics of cellular response is still poorly understood. We performed proteomic analysis to investigate the anticancer effect of kojic acid on protein expression profile in A375 cells. A375 cells were treated with kojic acid at 8 microg/mL for 24, 48, and 72 h. With the use of 2-D PAGE and MALDI-Q-TOF MS and MS/MS analyses, proteomic profiles of A375 cells between control and kojic acid treatment were compared, and 30 differentially expressed proteins, containing 2 up-regulated proteins and 28 down-regulated proteins, were identified. Among these proteins, 17 isoforms of 5 identical proteins were observed and 11 chaperone proteins showed the high proportion of protein spots with 36.7% of total proteins. Bioinformatic tools were used to search for protein function and prediction of protein interaction. Sixteen differentially expressed proteins exhibited interaction network linked to the downstream regulations of p53 tumor suppressor and cell apoptosis, which may lead to suppress the melanogenesis and tumorigenesis of kojic acid treated A375 cells. In addition, GRP75, VIME and 2AAA were validated by Western blot analysis, whereas GRP75, 2AAA, HS90B, ENPL and KPYM were validated by RT-PCR. Therefore, these proteins play the important roles in cancer progression and may be potential biomarkers that are useful for diagnostic and therapeutic applications of malignant melanoma cancer.  相似文献   
119.
Rottlerin is a widely selective protein kinase C delta (PKCdelta) inhibitor isolated from Mallotus philippinensis. It shown to be effective against several human tumor cell lines and in potentiating chemotherapy-induced cytotoxcicity. Using the trypan blue exclusion assay, we demonstrated that rottlerin reduced the viability in a dose- and time-dependent manner of human leukemia HL60 cells, human acute T cell leukemia Jurkat cells and mouse macrophage RAW 264.7 cells. Rottlerin caused apoptosis and the apaptotic processing was inhibited by a caspase inhibitor, z-VAD-fmk, in these haematopoietic cells. The apoptosis-inducing activities were determined by nuclear condensation, sub-G1 appearance, DNA fragmentation, loss of mitochondrial membrane potential (Deltapsim), release of mitochondrial cytochrome c into cytoplasm and proteolytic activation of caspase 9 and 3. Expression of PKCdelta and Bcl-2 protein inhibited Deltapsim change and repressed cell death. These studies suggest that the cytotoxic effects of rottlerin through inhibition of PKCdelta cause mitochondrial dysfunction, cytochrome c release from mitochondria into cytoplasm and the activation of caspases' cascade.  相似文献   
120.
再论DG指数的性质与应用   总被引:10,自引:2,他引:10  
密度-类群指数(DG指数)是为研究复杂的土壤动物群落多样性而创建的, 其理论基础是土壤动物群落中各类群互不干扰和互利的关系大于互相竞争的关系, 因而公式中各类群是互相独立、互不影响的.DG指数自1990年建立以来, 经作者及同行学者在不同地带、不同生态系统和不同级别的土壤动物群落研究中运用, 都获得良好的效果, 能真实地反映群落的多样性状况,显示出它具有广泛的适用性.用情景分析法(scenario analysis)探讨DG指数与Shannon-Wiener多样性指数(H')的预期效果, 结果显示, 当群落间种数差和均匀度(J)差为正负相反的数值时, Shannon-Wiener指数与DG指数不一致.文中还对土壤动物群落多样性的概念、性质及指数适用性进行了讨论, 认为土壤动物群落在客观上不存在均匀的数量分布, 把"均匀度"看作是多样性的重要指标是不适宜的.DG指数虽然没有直接包含许多信息, 但能在广泛的情况下经得起检验, 因而具有重要的应用价值.  相似文献   
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