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31.
32.
Monika Rottstegge Tom Tipton Lisa Oestereich Paula Ruibal Emily V. Nelson Catherine Olal Julia R. Port Johan Seibel Elisa Pallasch Sabrina Bockholt Fara Raymond Koundouno Joseph Akoi Bor Estefanía Rodríguez Beatriz Escudero-Prez Stephan Günther Miles W. Carroll Csar Muoz-Fontela 《Journal of virology》2022,96(18)
33.
Tomas Urbaitis Giedrius Gasiunas Joshua K Young Zhenglin Hou Sushmitha Paulraj Egle Godliauskaite Mantvyda M Juskeviciene Migle Stitilyte Monika Jasnauskaite Megumu Mabuchi G Brett Robb Virginijus Siksnys 《EMBO reports》2022,23(12)
Most CRISPR‐type V nucleases are stimulated to cleave double‐stranded (ds) DNA targets by a T‐rich PAM, which restricts their targeting range. Here, we identify and characterize a new family of type V RNA‐guided nuclease, Cas12l, that exclusively recognizes a C‐rich (5''‐CCY‐3′) PAM. The organization of genes within its CRISPR locus is similar to type II‐B CRISPR‐Cas9 systems, but both sequence analysis and functional studies establish it as a new family of type V effector. Biochemical experiments show that Cas12l nucleases function optimally between 37 and 52°C, depending on the ortholog, and preferentially cut supercoiled DNA. Like other type V nucleases, it exhibits collateral nonspecific ssDNA and ssRNA cleavage activity that is triggered by ssDNA or dsDNA target recognition. Finally, we show that one family member, Asp2Cas12l, functions in a heterologous cellular environment, altogether, suggesting that this new group of CRISPR‐associated nucleases may be harnessed as genome editing reagents. 相似文献
34.
Sophie-Marie Aicher Felix Streicher Maxime Chazal Delphine Planas Dongsheng Luo Julian Buchrieser Monika Nemcova Veronika Seidlova Jan Zukal Jordi Serra-Cobo Dominique Pontier Bertrand Pain Gert Zimmer Olivier Schwartz Philippe Roingeard Jiri Pikula Laurent Dacheux Nolwenn Jouvenet 《Journal of virology》2022,96(14)
35.
Phylogeny of calcareous dinoflagellates as inferred from ITS and ribosomal sequence data 总被引:6,自引:0,他引:6
Gottschling M Keupp H Plötner J Knop R Willems H Kirsch M 《Molecular phylogenetics and evolution》2005,36(3):3-455
The phylogenetic relationships of calcareous dinoflagellates (i.e., Calciodinellaceae and Thoracosphaera) are investigated. Molecular data from the ribosomal 5.8S rRNA and highly conserved motifs of the ITS1 show Calciodinellaceae s.l. to be monophyletic when few non-calcareous taxa are included. They segregate into three monophyletic assemblages in a molecular analysis that considers the 5.8S rRNA and both the Internal Transcribed Spacer regions ITS1 and ITS2: a clade comprising species of Ensiculifera and Pentapharsodinium (E/P-clade), Scrippsiella s.l. (including fossil-based taxa such as Calciodinellum and Calcigonellum), and a heterogeneous group (T/P-clade) of calcareous (e.g., Thoracosphaera) and non-calcareous taxa (e.g., the highly toxic Pfiesteria). The potential to produce calcareous structures is considered as apomorphic within alveolates, and non-calcareous taxa nesting with calcareous dinoflagellates may have reduced calcification secondarily. Molecular results do not contradict general evolutionary scenarios provided by previous morphological (mainly paleontological) investigations. 相似文献
36.
Garcia BA Hake SB Diaz RL Kauer M Morris SA Recht J Shabanowitz J Mishra N Strahl BD Allis CD Hunt DF 《The Journal of biological chemistry》2007,282(10):7641-7655
Post-translational modifications (PTMs) of histones play an important role in many cellular processes, notably gene regulation. Using a combination of mass spectrometric and immunobiochemical approaches, we show that the PTM profile of histone H3 differs significantly among the various model organisms examined. Unicellular eukaryotes, such as Saccharomyces cerevisiae (yeast) and Tetrahymena thermophila (Tet), for example, contain more activation than silencing marks as compared with mammalian cells (mouse and human), which are generally enriched in PTMs more often associated with gene silencing. Close examination reveals that many of the better-known modified lysines (Lys) can be either methylated or acetylated and that the overall modification patterns become more complex from unicellular eukaryotes to mammals. Additionally, novel species-specific H3 PTMs from wild-type asynchronously grown cells are also detected by mass spectrometry. Our results suggest that some PTMs are more conserved than previously thought, including H3K9me1 and H4K20me2 in yeast and H3K27me1, -me2, and -me3 in Tet. On histone H4, methylation at Lys-20 showed a similar pattern as H3 methylation at Lys-9, with mammals containing more methylation than the unicellular organisms. Additionally, modification profiles of H4 acetylation were very similar among the organisms examined. 相似文献
37.
Receptor for advanced glycation end products is subjected to protein ectodomain shedding by metalloproteinases 总被引:1,自引:0,他引:1
Zhang L Bukulin M Kojro E Roth A Metz VV Fahrenholz F Nawroth PP Bierhaus A Postina R 《The Journal of biological chemistry》2008,283(51):35507-35516
The receptor for advanced glycation end products (RAGE) is a 55-kDa type I membrane glycoprotein of the immunoglobulin superfamily. Ligand-induced up-regulation of RAGE is involved in various pathophysiological processes, including late diabetic complications and Alzheimer disease. Application of recombinant soluble RAGE has been shown to block RAGE-mediated pathophysiological conditions. After expression of full-length RAGE in HEK cells we identified a 48-kDa soluble RAGE form (sRAGE) in the culture medium. This variant of RAGE is smaller than a 51-kDa soluble version derived from alternative splicing. The release of sRAGE can be induced by the phorbol ester PMA and the calcium ionophore calcimycin via calcium-dependent protein kinase C subtypes. Hydroxamic acid-based metalloproteinase inhibitors block the release of sRAGE, and by RNA interference experiments we identified ADAM10 and MMP9 to be involved in RAGE shedding. In protein biotinylation experiments we show that membrane-anchored full-length RAGE is the precursor of sRAGE and that sRAGE is efficiently released from the cell surface. We identified cleavage of RAGE to occur close to the cell membrane. Ectodomain shedding of RAGE simultaneously generates sRAGE and a membrane-anchored C-terminal RAGE fragment (RAGE-CTF). The amount of RAGE-CTF increases when RAGE-expressing cells are treated with a gamma-secretase inhibitor, suggesting that RAGE-CTF is normally further processed by gamma-secretase. Identification of these novel mechanisms involved in regulating the availability of cell surface-located RAGE and its soluble ectodomain may influence further research in RAGE-mediated processes in cell biology and pathophysiology. 相似文献
38.
Induction of auxin biosynthetic enzymes by jasmonic acid and in clubroot diseased Chinese cabbage plants 总被引:14,自引:0,他引:14
Slobodanka Grsic Brigitte Kirchheim Kerstin Pieper Monika Fritsch Willy Hilgenberg Jutta Ludwig-Müller 《Physiologia plantarum》1999,105(3):521-531
Nitrilase (NIT) and myrosinase are important enzymes for auxin biosynthesis in Brassicaceae, which is increased during clubroot disease. Therefore, NIT and myrosinase levels during club development and possible regulation mechanisms were investigated. In addition, the occurrence of different nitrilase isoforms in Chinese cabbage has been shown. Nitrilase activity was enhanced in infected roots during later stages of club development (35–42 days after inoculation). However, no differences in nitrilase mRNA levels between infected and healthy roots were found during symptom development. Myrosinase expression was increased in clubbed roots at slightly earlier time points (28 days after inoculation) and also at later time points during infection. The activities of tryptophan oxidizing enzyme (TrpOxE), which catalyzes the first step in tryptophan-dependent auxin biosynthesis in Brassicaceae, and nitrilase were enhanced after treatment with jasmonic acid (JA) and methyl jasmonate. Similarly, the amount of myrosinase mRNA was increased by JA. During clubroot disease the endogenous concentration of JA increased in infected roots 3–5 weeks after inoculation. From our results it can be concluded that: (1) de novo indole-3-acetic acid (IAA) biosynthesis plays a role for symptom development of clubroot disease in Brassicaceae during later developmental stages; and (2) JA which increased during club development, may be involved in the up-regulation of three enzymes important for IAA synthesis. 相似文献
39.
Eggs of the elm leaf beetle Xanthogaleruca luteola are often heavily attacked by the chalcidoid wasp Oomyzus gallerucae. We studied the chemical signals mediating interactions between the egg parasitoid, its host, and the plant Ulmus campestris. Olfactometer bioassays with O. gallerucae showed that volatiles of the host-plant complex attract the parasitoid. In order to determine the source of attractive volatiles
within this host-plant-complex, we tested separately the effect of odours of eggs, gravid elm leaf beetle females, faeces
of the beetles and elm twigs (with undamaged leaves and leaves damaged either mechanically or by feeding of the beetles).
Odours of faeces of the elm leaf beetle were attractive, whereas neither volatiles from eggs nor from gravid females acted
as attractants. Volatiles from undamaged or damaged plants did not elicit a positive reaction in O. gallerucae, whereas volatiles from feeding-damaged plants onto which host eggs had been deposited were attractive. This latter result
suggests that it is not feeding but deposition of host eggs onto elm leaves that induces the production of plant volatiles
attractive to the egg parasitoid. Investigations of the search patterns of O. gallerucae within the habitat by laboratory bioassays revealed that the egg parasitoid encounters host eggs by chance. Contact kairomones
from faeces were demonstrated to be important in microhabitat acceptance, while contact kairomones isolated from the host
eggs are relevant for host recognition.
Received: 12 February 1997 / Accepted: 29 April 1997 相似文献
40.
A DNA barcode library for Germany′s mayflies,stoneflies and caddisflies (Ephemeroptera,Plecoptera and Trichoptera) 下载免费PDF全文
Jérôme Morinière Lars Hendrich Michael Balke Arne J. Beermann Tobias König Monika Hess Stefan Koch Reinhard Müller Florian Leese Paul D. N. Hebert Axel Hausmann Christoph D. Schubart Gerhard Haszprunar 《Molecular ecology resources》2017,17(6):1293-1307
Mayflies, stoneflies and caddisflies (Ephemeroptera, Plecoptera and Trichoptera) are prominent representatives of aquatic macroinvertebrates, commonly used as indicator organisms for water quality and ecosystem assessments. However, unambiguous morphological identification of EPT species, especially their immature life stages, is a challenging, yet fundamental task. A comprehensive DNA barcode library based upon taxonomically well‐curated specimens is needed to overcome the problematic identification. Once available, this library will support the implementation of fast, cost‐efficient and reliable DNA‐based identifications and assessments of ecological status. This study represents a major step towards a DNA barcode reference library as it covers for two‐thirds of Germany's EPT species including 2,613 individuals belonging to 363 identified species. As such, it provides coverage for 38 of 44 families (86%) and practically all major bioindicator species. DNA barcode compliant sequences (≥500 bp) were recovered from 98.74% of the analysed specimens. Whereas most species (325, i.e., 89.53%) were unambiguously assigned to a single Barcode Index Number (BIN) by its COI sequence, 38 species (18 Ephemeroptera, nine Plecoptera and 11 Trichoptera) were assigned to a total of 89 BINs. Most of these additional BINs formed nearest neighbour clusters, reflecting the discrimination of geographical subclades of a currently recognized species. BIN sharing was uncommon, involving only two species pairs of Ephemeroptera. Interestingly, both maximum pairwise and nearest neighbour distances were substantially higher for Ephemeroptera compared to Plecoptera and Trichoptera, possibly indicating older speciation events, stronger positive selection or faster rate of molecular evolution. 相似文献