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71.
Arabidopsis genes encoding mitochondrial type II NAD(P)H dehydrogenases have different evolutionary origin and show distinct responses to light 下载免费PDF全文
Michalecka AM Svensson AS Johansson FI Agius SC Johanson U Brennicke A Binder S Rasmusson AG 《Plant physiology》2003,133(2):642-652
In addition to proton-pumping complex I, plant mitochondria contain several type II NAD(P)H dehydrogenases in the electron transport chain. The extra enzymes allow the nonenergy-conserving electron transfer from cytoplasmic and matrix NAD(P)H to ubiquinone. We have investigated the type II NAD(P)H dehydrogenase gene families in Arabidopsis. This model plant contains two and four genes closely related to potato (Solanum tuberosum) genes nda1 and ndb1, respectively. A novel homolog, termed ndc1, with a lower but significant similarity to potato nda1 and ndb1, is also present. All genes are expressed in several organs of the plant. Among the nda genes, expression of nda1, but not nda2, is dependent on light and circadian regulation, suggesting separate roles in photosynthesis-associated and other respiratory NADH oxidation. Genes from all three gene families encode proteins exclusively targeted to mitochondria, as revealed by expression of green fluorescent fusion proteins and by western blotting of fractionated cells. Phylogenetic analysis indicates that ndc1 affiliates with cyanobacterial type II NADH dehydrogenase genes, suggesting that this gene entered the eukaryotic cell via the chloroplast progenitor. The ndc1 should then have been transferred to the nucleus and acquired a signal for mitochondrial targeting of the protein product. Although they are of different origin, the nda, ndb, and ndc genes carry an identical intron position. 相似文献
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73.
Andrew Harrison Hans Binder Arnaud Buhot Conrad J. Burden Enrico Carlon Cynthia Gibas Lara J. Gamble Avraham Halperin Jef Hooyberghs David P. Kreil Rastislav Levicky Peter A. Noble Albrecht Ott B. Montgomery Pettitt Diethard Tautz Alexander E. Pozhitkov 《Nucleic acids research》2013,41(5):2779-2796
Hybridization of nucleic acids on solid surfaces is a key process involved in high-throughput technologies such as microarrays and, in some cases, next-generation sequencing (NGS). A physical understanding of the hybridization process helps to determine the accuracy of these technologies. The goal of a widespread research program is to develop reliable transformations between the raw signals reported by the technologies and individual molecular concentrations from an ensemble of nucleic acids. This research has inputs from many areas, from bioinformatics and biostatistics, to theoretical and experimental biochemistry and biophysics, to computer simulations. A group of leading researchers met in Ploen Germany in 2011 to discuss present knowledge and limitations of our physico-chemical understanding of high-throughput nucleic acid technologies. This meeting inspired us to write this summary, which provides an overview of the state-of-the-art approaches based on physico-chemical foundation to modeling of the nucleic acids hybridization process on solid surfaces. In addition, practical application of current knowledge is emphasized. 相似文献
74.
Phosphorylation determines two distinct species of Tau in the central nervous system 总被引:35,自引:0,他引:35
The monoclonal antibody, Tau-1, which had previously been used to localize tau to the axonal compartment in brain has been reutilized for light and electron microscopic immunohistochemistry following phosphatase treatment of tissue. We report here that a significant quantity of tau in the central nervous system is phosphorylated in situ at or near the Tau-1 epitope, preventing the binding of the Tau-1 antibody. Upon removal of this/these phosphate group(s), however, Tau-1 was observed in the somatodendritic compartment of neurons as well as in axons. Furthermore, intense staining was also observed in astrocytes and in perineuronal glial cells. This immunoreactivity was present along the lengths of microtubules and on ribosomes (polysomes). Treatment of immunoblots of extracts of whole cerebral cortex with phosphatase confirmed the immunohistochemical results in that a 50-65% increase in Tau-1 binding to the tau region of the blot was noted. Moreover, a novel monoclonal antibody, Tau-2, was also used in these experiments. This antibody binds only to tau and localizes along microtubules in axons, somata, dendrites, and astrocytes and on ribosomes (polysomes) without phosphatase pretreatment. 相似文献
75.
Bothia is described as a new genus in the Boletaceae based on Boletinus castanellus described by C.H. Peck from eastern North America. A widespread, occasionally encountered taxon, Bothia castanella possesses a combination of macro- and microscopic features that has prompted past placement in seven different genera. Yet, as a species it is readily recognizable with its chestnut brown, dry pileus, decurrent, pale brown hymenophore with radially elongated tubes, a short, sometimes eccentric, exannulate stipe, yellow brown spore deposit and constant association with Quercus. Phylogenetic analyses of large subunit rDNA and BLAST searches using the ITS region confirm the placement of B. castanella as a unique generic lineage in the Boletaceae. 相似文献
76.
Binder H 《European biophysics journal : EBJ》2007,36(4-5):265-279
The ordering and H-bonding characteristics of the hydration water of the lipid 1-palmitoyl-2-oleoylphosphatidylcholine (POPC)
were studied using polarized infrared spectroscopy by varying either the temperature or the relative humidity of the ambient
atmosphere of multibilayer samples. The OH-stretching band of lipid-bound water was interpreted by a simplified two-state
model of well-structured, low density “network” water and of less-structured dense “multimer” water. The IR-spectroscopic
data reflect a rather continuous change of the water properties with increasing distance from the membrane and with changing
temperature. Network and multimer water distribute across the whole polar interphase with changing composition and orientation.
Upon dehydration the fraction of network water increases from about 30 to 60%, a value which is similar to that in supercooled
water at −25°C. The highly ordered gel phase gives rise to an increased fraction of structured network water compared with
the liquid crystalline phase. The IR order parameter shows that the water dipoles rearrange from a more parallel towards a
more perpendicular orientation with respect to the membrane normal with progressive hydration.
Dedicated to Prof. K. Arnold on the occasion of his 65th birthday. 相似文献
77.
Bach Vanessa Hélias Arnaud Muhl Marco Wojciechowski Aurélie Bosch Henk Binder Michael Finkbeiner Matthias 《The International Journal of Life Cycle Assessment》2022,27(4):573-586
The International Journal of Life Cycle Assessment - Overfishing has been a global challenge for several decades with severe impacts on biodiversity and ecosystem services. Several approaches for... 相似文献
78.
Jason D. Thiem Mark K. Taylor Sarah H. McConnachie Thomas R. Binder Steven J. Cooke 《Reviews in Fish Biology and Fisheries》2011,21(1):117-126
The intracoelomic surgical implantation of telemetry transmitters in fish is becoming the “standard” tagging approach for
most field telemetry studies. Subsequently, efforts must be made to ensure the welfare of the fish are maintained and that
fish do not experience significant mortality or sublethal impairments in health, behavior or physiology as a result of surgical
procedures. Therefore, it is essential to adequately report information relating to all aspects of the surgical procedure
to enable the reader to make an accurate interpretation of study results. We conducted a quantitative literature review aimed
at characterizing trends in data reporting by examining a sample of fish telemetry studies published in peer-reviewed outlets
during the last 20 years. We used a repeatability score, based on 16 predetermined criteria, to evaluate the reporting of
surgical procedures in telemetry studies. The majority of studies failed to report basic information relating to the surgical
procedures used. Repeatability scores were highly variable between studies and ranged from 0–93.8%. No single study provided
complete information (mean repeatability score = 50.7%) and repeatability showed no trend over time. Some study information
was consistently well reported (e.g. tag size and dimensions, the type of anaesthetic used and the location of incision).
In contrast, the type of suture knots, duration or level of anaesthesia and precautions taken to minimize infection were consistently
left out of the methods section of most telemetry studies. Our review was confounded by the large proportion of studies that
cited other sources for their surgical methods, many of which themselves lacked complete information. We recommend that future
electronic tagging studies that involve intracoelomic implantation include the minimum reporting standards presented in this
paper. Increasing the detail of reporting will improve the quality of data presented, minimize welfare and ethical concerns
and allow transparency for study repeatability. 相似文献
79.
80.
Ma GZ Stankovich J;Australia New Zealand Multiple Sclerosis Genetics Consortium 《PloS one》2011,6(2):e16964
Multiple sclerosis (MS) is a debilitating, chronic demyelinating disease of the central nervous system affecting over 2 million people worldwide. The TAM family of receptor tyrosine kinases (TYRO3, AXL and MERTK) have been implicated as important players during demyelination in both animal models of MS and in the human disease. We therefore conducted an association study to identify single nucleotide polymorphisms (SNPs) within genes encoding the TAM receptors and their ligands associated with MS. Analysis of genotype data from a genome-wide association study which consisted of 1618 MS cases and 3413 healthy controls conducted by the Australia and New Zealand Multiple Sclerosis Genetics Consortium (ANZgene) revealed several SNPs within the MERTK gene (Chromosome 2q14.1, Accession Number NG_011607.1) that showed suggestive association with MS. We therefore interrogated 28 SNPs in MERTK in an independent replication cohort of 1140 MS cases and 1140 healthy controls. We found 12 SNPs that replicated, with 7 SNPs showing p-values of less than 10(-5) when the discovery and replication cohorts were combined. All 12 replicated SNPs were in strong linkage disequilibrium with each other. In combination, these data suggest the MERTK gene is a novel risk gene for MS susceptibility. 相似文献