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844.
Coleopteran phylogeny was analysed using mitochondrial genome (mitogenome) sequence. The optimal tree topology was given by the dataset consisted of all coding genes except for the exclusion of the 3rd codon sites (mtDNA12) using Bayesian Inference Method. This topology supports the monophyly of four suborders, and the sister group relationship between Adephaga and Myxophaga and between Polyphaga and Archostemata. In Polyphaga, Cucujiformia and Elateroidea formed independent node respectively, the remaining species grouped together except for Cyphon sp, among which, only Cucujiformia and Scarabaeiformia were supported as monophyletic group, respectively. Within Cucujiformia, the monophyly of Chrysomeloidea, Curculionoidea and Tenebrionoidea were supported respectively, among which Tenebrionoidea occupied the basal position of Cucujiformia. Cleroidea grouped together with Bothrideridae and Coccinellidae, and formed an independent node, which lead to the paraphyly of Cucujoidea. The monophyly of Elateriformia was not supported because of the division of Scirtoidea and Buprestoidea. Furthermore, using a Bayesian relaxed clock calibrated with fossil data, we estimated that most superfamilies within Polyphaga originated in the Jurassic period.  相似文献   
845.
Mammals have co‐evolved with retroviruses, including lentiviruses, over a long period. Evidence supporting this contention is that viral infectivity factor (Vif) encoded by lentiviruses antagonizes the anti‐viral action of cellular apolipoprotein B mRNA editing enzyme catalytic polypeptide‐like 3 (APOBEC3) of the host. To orchestrate E3 ubiquitin ligase complex for APOBEC3 degradation, Vifs utilize mammalian proteins such as core‐binding factor beta (CBFB; for primate lentiviruses) or cyclophilin A (CYPA; for Maedi–Visna virus [MVV]). However, the co‐evolutionary relationship between lentiviral Vif and the mammalian proteins associated with Vif‐mediated APOBEC3 degradation is poorly understood. Moreover, it is unclear whether Vif proteins of small ruminant lentiviruses (SRLVs), including MVV and caprine arthritis encephalitis virus (CAEV), commonly utilize CYPA to degrade the APOBEC3 of their hosts. In this study, molecular phylogenetic and protein homology modeling revealed that Vif co‐factors are evolutionarily and structurally conserved. It was also found that not only MVV but also CAEV Vifs degrade APOBEC3 of both sheep and goats and that CAEV Vifs interact with CYPA. These findings suggest that lentiviral Vifs chose evolutionarily and structurally stable proteins as their partners (e.g., CBFB or CYPA) for APOBEC3 degradation and, particularly, that SRLV Vifs evolved to utilize CYPA as their co‐factor in degradation of ovine and caprine APOBEC3.  相似文献   
846.
Myxomycetes or plasmodial slime molds are widespread and very common soil amoebae with the ability to form macroscopic fruiting bodies. Even if their phylogenetic position as a monophyletic group in Amoebozoa is well established, their internal relationships are still not entirely resolved. At the base of the most intensively studied dark‐spored clade lies the order Echinosteliales, whose highly divergent small subunit ribosomal (18S) RNA genes represent a challenge for phylogenetic reconstructions. This is because they are characterized by unusually long variable helices of unknown secondary structure and a high inter‐ and infraspecific divergence. Current classification recognizes two families: the monogeneric Echinosteliaceae and the Clastodermataceae with the genera Barbeyella and Clastoderma. To better resolve the phylogeny of the Echinosteliales, we obtained three new small subunit ribosomal (18S) RNA gene sequences of Clastoderma and Echinostelium corynophorum. Our phylogenetic analyses suggested the polyphyly of the family Clastodermataceae, as Barbeyella was more closely related to Echinostelium arboreum than to Clastoderma, while Clastoderma debaryanum was the earliest branching clade in Echinosteliales. We also found that E. corynophorum was the closest relative of the enigmatic Semimorula liquescens, a stalkless‐modified Echinosteliales. We discuss possible evolutionary pathways in dark‐spored Myxomycetes and propose a taxonomic update.  相似文献   
847.
Hepatitis B virus (HBV) produces large (L), middle (M), and small (S) envelope proteins, alternatively referred to as hepatitis B surface antigen (HBsAg). Currently, yeast-derived S protein serves as the preventive vaccine, while hepatitis B immune globulin (HBIG) concentrated from pooled plasma of vaccine recipients is employed for post-exposure prophylaxis. However, only a small proportion of the antibodies in HBIG are HBV specific. In the present study, a human monoclonal anti-S antibody (G12) was developed, produced under GLP conditions, and subjected to a panel of functional assays. In vitro results demonstrated high affinity of G12 for the S protein (KD = 7.56 nM). It reacted with envelope proteins of all 7 HBV genotypes tested (A-F, H) by immunofluorescent staining, and more than 97% of HBsAg-positive patient serum samples by enzyme-linked immunosorbent assay. G12 recognized a conformational epitope, although the exact sequence remains unknown. Strikingly, G12 was at least 1,000-fold more potent than HBIG in neutralizing HBV infectivity in both HepaRG cell line and HepG2 cells reconstituted with the HBV receptor. In a transgenic mouse model of HBV persistence, a single peritoneal injection of G12 markedly diminished serum HBsAg titers in all 7 mice, which was sustained for the observation period of 144 d in mice with low pre-treatment levels. While the therapeutic potential of G12 warrants further investigation using a large number of animals, G12 is a potent neutralizing human monoclonal antibody and a promising candidate to replace or supplement HBIG in the prevention of HBV infection.  相似文献   
848.
Tyrosine kinase inhibitors, such as erlotinib, display reliable responses and survival benefits for the treatment of human non‐small cell lung cancer (NSCLC) patients. However, primary or acquired resistance limits their therapeutic success. In this study, we conducted in‐depth mass spectrometric analyses of NSCLC cell secretomes. To identify secreted proteins that are differentially regulated in erlotinib‐sensitive (PC‐9) and ‐resistant (PC‐9ER) NSCLC cell lines, SILAC experiments were performed. On average, 900 proteins were identified in each sample with low variations in the numbers of identified proteins. Fourteen proteins were found to be differently regulated among erlotinib‐sensitive and ‐resistant NSCLC cell lines, with five proteins (tissue‐type plasminogen activator, epidermal growth factor receptor, urokinase‐type plasminogen activator, platelet‐derived growth factor D, and myeloid‐derived growth factor) showing the most prominent regulation. Tissue‐type plasminogen activator (t‐PA) was up to 10‐times upregulated in erlotinib‐resistant NSCLC cells compared with erlotinib‐sensitive cells. T‐PA is an established tumor marker for various cancer types and seems to be a promising prognostic marker to differentiate erlotinib‐sensitive from erlotinib‐resistant NSCLC cells. To gain further insights into t‐PA‐regulated pathways, a t‐PA variant was expressed in E. coli cells and its interactions with proteins secreted from erlotinib‐sensitive and ‐resistant NCSLC cells were studied by a combined affinity enrichment chemical cross‐linking/mass spectrometry (MS) approach. Fourteen proteins were identified as potential t‐PA interaction partners, deserving a closer inspection to unravel the mechanisms underlying erlotinib resistance in NSCLC cells.  相似文献   
849.
This paper reviews strategies and methods to improve accuracies of genomic predictions from the perspective of a numerically small population. Improvements are realized by influencing one or both of the main factors: (1) improve or increase genomic connections to phenotypic records in training data. (2) Models and strategies to focus genomic predictions on markers closer to the causative variants. Combining populations into a joint reference population results in high improvements when combining populations of the same breed and diminishes as the genetic distance between populations increases. For distantly related breeds sophisticated Bayesian variable selection models in combination with denser markers sets or functional subsets of markers is needed. This is expected to be further improved by the efficient use of sequence information. In addition predictions can be improved by the use of phenotypes of genotyped and non-genotyped cows directly. For a small population the optimal approach will combine the above components.  相似文献   
850.
目的:研究CD133蛋白在非小细胞肺癌(NSCLC)组织中的表达及其与临床病理参数及预后的关系。方法:选择2011年4月~2012年4月间我院收治的42例NSCLC的临床资料,采用免疫组织化学染色法检测癌组织和其中30例癌旁边正常组织CD133的表达,并分析其与肺癌临床病理参数及预后的关系。结果:癌症组织CD133蛋白阳性表达率为57.1%,高于癌旁边正常组织的16.7%,差异有统计学意义(P均0.05);CD133蛋白阳性表达与NSCLC患者年龄、性别以及肿瘤大小、肿瘤位置、组织学类型、组织分化程度以及不同临床分期无关(均P0.05),与淋巴结转移有关,差异有统计学意义(P0.05);CDD133阳性及阴性患者近3年生存率比较,1年生存率比较差异不显著(P0.05),2、3年生存率比较,差异显著有统计学意义(P0.05)。结论:CD133蛋白在NSCLC组织中的高表达,且与NSCLC转移及预后密切相关,对于患者临床特征及预后的关系具有重要的研究价值。  相似文献   
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