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101.
In the northwestern Bering Sea in autumn, the epipelagic cephalopod community was represented by the boreal fauna, and was
found to be composed of three families and nine species of the order Teuthida: Gonatidae (Berryteuthis magister, Boreoteuthis borealis, Gonatopsis japonicus, Gonatus madokai, Gonatus kamtschaticus, Gonatus onyx, and Gonatus pyros), Chiroteuthidae (Chiroteuthis calyx) and Onychoteuthidae (Onychoteuthis borealijaponica). Two pelagic gonatid species (B. borealis and G. kamtschaticus) dominated the cephalopod community in the upper 50 m. The distribution patterns of B. borealis and G. onyx were associated with diel vertical migrations of these squid. The distribution of two distinct size groups of G. kamtschaticus suggested ontogenetic migration of larger squid to deeper layers, and adds to previous data suggesting that this species
may be a heterogeneous assemblage. Demersal B. magister rarely occurred in the surface waters. The occurrence of maturing O. borealijaponica in the southern marine area indicated that these were occasional seasonal migrants from the ocean. The occurrence of juvenile
C. calyx suggested that these squid may conduct vertical forage migrations from deep waters to the surface layers. 相似文献
102.
Comparative analysis of the complete genome sequence of the plant growth-promoting bacterium Bacillus amyloliquefaciens FZB42 总被引:11,自引:0,他引:11
Chen XH Koumoutsi A Scholz R Eisenreich A Schneider K Heinemeyer I Morgenstern B Voss B Hess WR Reva O Junge H Voigt B Jungblut PR Vater J Süssmuth R Liesegang H Strittmatter A Gottschalk G Borriss R 《Nature biotechnology》2007,25(9):1007-1014
Bacillus amyloliquefaciens FZB42 is a Gram-positive, plant-associated bacterium, which stimulates plant growth and produces secondary metabolites that suppress soil-borne plant pathogens. Its 3,918-kb genome, containing an estimated 3,693 protein-coding sequences, lacks extended phage insertions, which occur ubiquitously in the closely related Bacillus subtilis 168 genome. The B. amyloliquefaciens FZB42 genome reveals an unexpected potential to produce secondary metabolites, including the polyketides bacillaene and difficidin. More than 8.5% of the genome is devoted to synthesizing antibiotics and siderophores by pathways not involving ribosomes. Besides five gene clusters, known from B. subtilis to mediate nonribosomal synthesis of secondary metabolites, we identified four giant gene clusters absent in B. subtilis 168. The pks2 gene cluster encodes the components to synthesize the macrolactin core skeleton. 相似文献
103.
Tsinkalovsky O Smaaland R Rosenlund B Sothern RB Hirt A Steine S Badiee A Abrahamsen JF Eiken HG Laerum OD 《Journal of biological rhythms》2007,22(2):140-150
Time-dependent variations in clock gene expression have recently been observed in mouse hematopoietic cells, but the activity of these genes in human bone marrow (BM) has so far not been investigated. Since such data can be of considerable clinical interest for monitoring the dynamics in stem/progenitor cells, the authors have studied mRNA expression of the clock genes hPer1 , hPer2, hCry1, hCry2, hBmal1, hRev-erb alpha, and hClock in human hematopoietic CD34-positive (CD34( +)) cells. CD34(+) cells were isolated from the BM samples obtained from 10 healthy men at 6 times over 24 h. In addition, clock gene mRNA expression was analyzed in the whole BM in 3 subjects. Rhythms in serum cortisol, growth hormone, testosterone, and leukocyte counts documented that subjects exhibited standardized circadian patterns. All 7 clock genes were expressed both in CD34(+) cells and the whole BM, with some differences in magnitude between the 2 cell populations. A clear circadian rhythm was shown for hPer1, hPer2, and hCry2 expression in CD34(+) cells and for hPer1 in the whole BM, with maxima from early morning to midday. Similar to mouse hematopoietic cells, h Bmal1 was not oscillating rhythmically. The study demonstrates that clock gene expression in human BM stem/progenitor cells may be developmentally regulated, with strong or weaker circadian profiles as compared to those reported in other mature tissues. 相似文献
104.
105.
Studneva Irina M. Veselova Oksana M. Dobrokhotov Igor V. Serebryakova Larisa I. Palkeeva Marina E. Molokoedov Alexander S. Azmuko Andrey A. Ovchinnikov Michael V. Sidorova Maria V. Pisarenko Oleg I. 《Biochemistry. Biokhimii?a》2022,87(4):346-355
Biochemistry (Moscow) - Neuropeptide galanin and its N-terminal fragments reduce the generation of reactive oxygen species and normalize metabolic and antioxidant states of myocardium in... 相似文献
106.
The Psp system of Mycobacterium tuberculosis integrates envelope stress‐sensing and envelope‐preserving functions 下载免费PDF全文
107.
Michael Seyffert Daniel L. Glauser Kurt Tobler Oleg Georgiev Rebecca Vogel Bernd Vogt Leticia Agúndez Michael Linden Hildegard Büning Mathias Ackermann Cornel Fraefel 《Journal of virology》2015,89(21):11150-11158
Adeno-associated virus type 2 is known to inhibit replication of herpes simplex virus 1 (HSV-1). This activity has been linked to the helicase- and DNA-binding domains of the Rep68/Rep78 proteins. Here, we show that Rep68 can bind to consensus Rep-binding sites on the HSV-1 genome and that the Rep helicase activity can inhibit replication of any DNA if binding is facilitated. Therefore, we hypothesize that inhibition of HSV-1 replication involves direct binding of Rep68/Rep78 to the HSV-1 genome. 相似文献
108.
Oleg V. Stroganov Fedor N. Novikov Alexey A. Zeifman Viktor S. Stroylov Ghermes G. Chilov 《Proteins》2011,79(9):2693-2710
A new graph–theoretical approach called thermodynamic sampling of amino acid residues (TSAR) has been elaborated to explicitly account for the protein side chain flexibility in modeling conformation‐dependent protein properties. In TSAR, a protein is viewed as a graph whose nodes correspond to structurally independent groups and whose edges connect the interacting groups. Each node has its set of states describing conformation and ionization of the group, and each edge is assigned an array of pairwise interaction potentials between the adjacent groups. By treating the obtained graph as a belief‐network—a well‐established mathematical abstraction—the partition function of each node is found. In the current work we used TSAR to calculate partition functions of the ionized forms of protein residues. A simplified version of a semi‐empirical molecular mechanical scoring function, borrowed from our Lead Finder docking software, was used for energy calculations. The accuracy of the resulting model was validated on a set of 486 experimentally determined pKa values of protein residues. The average correlation coefficient (R) between calculated and experimental pKa values was 0.80, ranging from 0.95 (for Tyr) to 0.61 (for Lys). It appeared that the hydrogen bond interactions and the exhaustiveness of side chain sampling made the most significant contribution to the accuracy of pKa calculations. Proteins 2011; © 2011 Wiley‐Liss, Inc. 相似文献
109.
Oleg M Alekseev Richard T Richardson James K Tsuruta Michael G O'Rand 《Reproductive biology and endocrinology : RB&E》2011,9(1):50
Background
NASP (Nuclear Autoantigenic Sperm Protein) is a histone chaperone that is present in all dividing cells. NASP has two splice variants: tNASP and sNASP. Only cancer, germ, transformed, and embryonic cells have a high level of expression of the tNASP splice variant. We examined the consequences of tNASP depletion for prostate cancer PC-3 cells. 相似文献110.
Chertov O Zhang N Chen X Oppenheim JJ Lubkowski J McGrath C Sowder RC Crise BJ Malyguine A Kutzler MA Steele AD Henderson EE Rogers TJ 《PloS one》2011,6(1):e14474
The sequential interaction of the envelope glycoprotein of the human immunodeficiency virus type 1 (HIV-1) with CD4 and certain chemokine coreceptors initiates host cell entry of the virus. The appropriate chemokines have been shown to inhibit viral replication by blocking interaction of the gp120 envelope protein with the coreceptors. We considered the possibility that this interaction involves a motif of the gp120 that may be structurally homologous to the chemokines. In the amino acid sequences of most chemokines there is a Trp residue located at the beginning of the C-terminal α-helix, which is separated by six residues from the fourth Cys residue. The gp120 of all HIV-1 isolates have a similar motif, which includes the C-terminal part of a variable loop 3 (V3) and N-terminal part of a conserved region 3 (C3). Two synthetic peptides, derived from the relevant gp120 sequence inhibited HIV-1 replication in macrophages and T lymphocytes in sequence-dependent manner. The peptides also prevented binding of anti-CXCR4 antibodies to CXCR4, and inhibited the intracellular Ca(2+) influx in response to CXCL12/SDF-1α. Thus these peptides can be used to dissect gp120 interactions with chemokine receptors and could serve as leads for the design of new inhibitors of HIV-1. 相似文献