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901.
Recent advances in nanotechnology have provided various nanoscale materials that can be used as support for enzyme immobilization. Nanobiocatalysis integrating the biocatalyst and nanoscale materials is drawing great attention as innovative technology. Nanobiocatalysis could achieve not only a much higher enzyme loading capacity and a significantly enhanced mass transfer efficiency, but also unbelievable stabilization. In this review, we will present and discuss the recent progress in nanobiocatalysis and its applications in the fields of bioelectronics, bioconversion, and proteomics. 相似文献
902.
Cretaceous shallow-marine carbonate rocks of SW Slovenia were deposited in the northern part of the Adriatic Carbonate Platform. A 560-m-thick continuous Upper Cenomanian to Santonian carbonate succession has been studied near Hru?ica Village in Matarsko Podolje. With regard to lithological, sedimentological, and stratigraphical characteristics, the succession has been divided into nine lithostratigraphic units, mainly reflecting regressive and transgressive intervals of larger scale. During the latest Cenomanian and Early Turonian, hemipelagic limestones were deposited on top of shallow-marine lagoon and peritidal Upper Cenomanian deposits indicating relative sea-level rise. Subsequently, the deeper marine depositional setting was gradually filled by clinoform bioclastic sand bodies overlain by peritidal and shallow-marine low-energy mainly lagoonal lithofacies. Similar lithofacies of predominately inner ramp/shelf depositional settings prevail over the upper part (i.e., Coniacian to Santonian) of the succession. In the area, the Upper Cetaceous carbonate rocks are separated from the overlying Lower Eocene (Upper Paleocene?) carbonate sequence by regional unconformity denoted by distinct paleokarstic features. On the Adriatic Carbonate Platform the deeper marine carbonate setting, developed at the Cenomanian/Turonian boundary, is usually correlated with OAE2 and related eustatic sea-level rise. Similarly, subsequent reestablished shallow-marine conditions are related to Late Turonian long- and short-term sea-level fall. However, we are suggesting that deeper marine deposits were deposited in a tectonically induced intraplatform basin formed simultaneously with the uplift of the northern and northeastern marginal parts of the Adriatic Carbonate Platform. 相似文献
903.
Sang-Hyun Lee Jin-Man Kim Dong Gwang Lee Jangwook Lee Jong-Gil Park Tae-Su Han Hyun-Soo Cho Young-Lai Cho Kwang-Hee Bae Young-Jun Park Seon-Jin Lee Moo-Seung Lee Yong-Min Huh Deog Yeon Jo Hwan-Jung Yun Heung Jin Jeon Nayoung Kim Mina Joo Jang-Seong Kim Hyo Jin Lee Jeong-Ki Min 《Cell death and differentiation》2021,28(3):968
Gallbladder carcinoma (GBC) exhibits poor prognosis due to local recurrence, metastasis, and resistance to targeted therapies. Using clinicopathological analyses of GBC patients along with molecular in vitro and tumor in vivo analysis of GBC cells, we showed that reduction of Dsg2 expression was highly associated with higher T stage, more perineural, and lymphatic invasion. Dsg2-depleted GBC cells exhibited significantly enhanced proliferation, migration, and invasiveness in vitro and tumor growth and metastasis in vivo through Src-mediated signaling activation. Interestingly, Dsg2 binding inhibited Src activation, whereas its loss activated cSrc-mediated EGFR plasma membrane clearance and cytoplasmic localization, which was associated with acquired EGFR-targeted therapy resistance and decreased overall survival. Inhibition of Src activity by dasatinib enhanced therapeutic response to anti-EGFR therapy. Dsg2 status can help stratify predicted patient response to anti-EGFR therapy and Src inhibition could be a promising strategy to improve the clinical efficacy of EGFR-targeted therapy.Subject terms: Tumour biomarkers, Tumour-suppressor proteins 相似文献
904.
Jae Young Choi Yang-Su Kim Yong Wang Sang Woon Shin Iksoo Kim Xue Ying Tao Qin Liu Jong Yul Roh Jae Su Kim Yeon Ho Je 《Journal of Asia》2012,15(2):259-263
The complete genome sequence and the gene organization of a novel insect picorna-like virus, Spodoptera exigua virus (SeV), were determined. The genomic RNA of the SeV was 9501 nt in length excluding the poly(A) tail and contained a single, large open reading frame (nt 392–9424) encoding a 3010 aa polyprotein. Sequence comparisons with other viral polyproteins revealed that the consensus sequences for picornavirus RNA helicase, cysteine protease, and RNA-dependent RNA polymerase (RdRp) proteins are found on the genome in that order from the 5′ to the 3′ end. In terms of sequence similarity, identity, and genome organization, SeV resembled insect picorna-like viruses belonging to the genus Iflavirus. A phylogenetic analysis based on the eight conserved domains in the RdRp sequence showed that SeV was most closely related to the Perina nuda virus and Ectropis obliqua picorna-like virus, suggesting that these three insect picorna-like viruses might share a common ancestor. 相似文献
905.
906.
Bacillus thuringiensis strains non-toxic to Lepidoptera, Bombyx mori and Diptera, Culex pipiens pallens larvae were isolated from Korean soil samples during an investigation of B. thuringiensis isolates highly toxic to insect pests. One of these isolates, NTB-88, produces parasporal inclusions about 138 kDa in size and is non-toxic to 19 insect species of three orders, Lepidoptera, Diptera and Coleoptera, even though it is highly susceptible to tryptic cleavage. Study of flagellar (H) antibodies of 33 B. thuringiensis strains revealed that NTB-88 has an H antigen identical with that of subsp. morrisoni (serotype 8a8b). Comparison of parasporal inclusion proteins and plasmid DNA patterns of strain NTB-88 with B. thuringiensis subsp. morrisoni HD-12 and B. thuringiensis subsp. morrisoni PG-14 showed that the isolate is a novel non-insecticidal B. thuringiensis strain belonging to serotype 8a8b. 相似文献
907.
908.
Katarína Smolková Nadège Bellance Francesca Scandurra Elisabeth Génot Erich Gnaiger Lydie Plecitá-Hlavatá Petr Ježek Rodrigue Rossignol 《Journal of bioenergetics and biomembranes》2010,42(1):55-67
Breast cancer cells can survive and proliferate under harsh conditions of nutrient deprivation, including limited oxygen and
glucose availability. We hypothesized that such environments trigger metabolic adaptations of mitochondria, which promote
tumor progression. Here, we mimicked aglycemia and hypoxia in vitro and compared the mitochondrial and cellular bioenergetic
adaptations of human breast cancer (HTB-126) and non-cancer (HTB-125) cells that originate from breast tissue. Using high-resolution
respirometry and western blot analyses, we demonstrated that 4 days of glucose deprivation elevated oxidative phosphorylation
five-fold, increased the spread of the mitochondrial network without changing its shape, and decreased the apparent affinity
of oxygen in cancer cells (increase in C
50
), whereas it remained unchanged in control cells. The substrate control ratios also remained constant following adaptation.
We also observed the Crabtree effect, specifically in HTB-126 cells. Likewise, sustained hypoxia (1% oxygen during 6 days)
improved cell respiration in non-cancer cells grown in glucose or glucose-deprived medium (+ 32% and +38%, respectively).
Conversely, under these conditions of limited oxygen or a combination of oxygen and glucose deprivation for 6 days, routine
respiration was strongly reduced in cancer cells (−36% in glucose medium, −24% in glucose-deprived medium). The data demonstrate
that cancer cells behave differently than normal cells when adapting their bioenergetics to microenvironmental conditions.
The differences in hypoxia and aglycemia tolerance between breast cancer cells and non-cancer cells may be important when
optimizing strategies for the treatment of breast cancer. 相似文献
909.
Henrik Kusche Hyuk Je Lee Axel Meyer 《Proceedings. Biological sciences / The Royal Society》2012,279(1748):4715-4723
Individuals of the scale-eating cichlid fish, Perissodus microlepis, from Lake Tanganyika tend to have remarkably asymmetric heads that are either left-bending or right-bending. The ‘left’ morph opens its mouth markedly towards the left and preferentially feeds on the scales from the right-hand side of its victim fish, and the ‘right’ morph bites scales from the victims’ left-hand side. This striking dimorphism made these fish a textbook example of their astonishing degree of ecological specialization and as one of the few known incidences of negative frequency-dependent selection acting on an asymmetric morphological trait, where left and right forms are equally frequent within a species. We investigated the degree and the shape of the frequency distribution of head asymmetry in P. microlepis to test whether the variation conforms to a discrete dimorphism, as generally assumed. In both adult and juvenile fish, mouth asymmetry appeared to be continuously and unimodally distributed with no clear evidence for a discrete dimorphism. Mixture analyses did not reveal evidence of a discrete or even strong dimorphism. These results raise doubts about previous claims, as reported in textbooks, that head variation in P. microlepis represents a discrete dimorphism of left- and right-bending forms. Based on extensive field sampling that excluded ambiguous (i.e. symmetric or weakly asymmetric) individual adults, we found that left and right morphs occur in equal abundance in five populations. Moreover, mate pairing for 51 wild-caught pairs was random with regard to head laterality, calling into question reports that this laterality is maintained through disassortative mating. 相似文献
910.
Lenka Jeřábková Guillaume Bousquet Sébastien Barbier François Faure Jérémie Allard 《Progress in biophysics and molecular biology》2010,103(2-3):217-224
A new approach for the interactive simulation of viscoelastic object cutting is presented. Two synchronized geometrical models at different resolutions are used, both derived from medical images. In contrast with most previous approaches, the blade deforms the object, and cutting occurs once a contact pressure threshold is exceeded. Moreover, we achieve interactive simulation rates by embedding a high-resolution geometry within a regular grid with arbitrary resolution. This allows to trade off accuracy for speed in the computation of deformations. The input data is a high-resolution volumetric model of the objects. The surface model of the object, used for rendering as well as collision detection and response, is a polygonal level set of the volumetric data. It is embedded in the volume model using barycentric coordinates.Cutting is performed by removing voxels at the fine level, and updating the surface and volume models accordingly. We introduce a new data structure, which we call a Dynamic Branched Grid, in order to preserve the fine-level topology at the coarse level. When an element of the coarse volumetric model is cut, it is replaced by a number of superimposed elements with the same size and at the same rest position as the original one. Each new element is assigned a part of material contained in the original one, and the mass and stiffness are recomputed accordingly. The well-known problem of creating small, ill-shaped finite elements while remeshing is thus completely avoided. 相似文献