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111.
Bernhard Hassenstein 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1951,33(4):301-326
Zusammenfassung Das ZNS des Grünkäfers (Chlorophanus viridis, Curculionidae) integriert gleichmäßige Folgen von Hell- und Dunkelreizen zu einer gleichsinnigen Bewegung, Wechselfolgen von Hell- und Dunkelreizen aber zu einer gegensinnigen Bewegung.Sein ZNS vermag zwei Helligkeitsreize auch über ein ungereiztes Ommatidium hinweg zu einer Bewegung zu integrieren (II,2), und zwar in allen geometrisch möglichen Richtungen (III, 1b).Die elementare physiologische Struktur für die Bewegungsperzeption besteht bei Chlorophanus aus zwei einzelnen Sehelementen.Die untere Schwelle für die Perzeption langsamer optischer Bewegungen liegt bei oder tiefer als 1,3°/min.Die Seitentendenzen, die sich in den Wahlen am Spangenglobus auswirken, erweisen sich als zuverlässiger Indikator für geometrische Interferenzbewegungen, die durch wandernde Streifenmuster kleiner Streifenbreite am Ommatidienraster entstehen.Nicht nach den Hauptrichtungen orientierte Ommatidienraster erzeugen mit Streifenmustern geringer Konstanten Interferenzbewegungen mit senkrechter Bewegungskomponente.Aus den Reaktionen auf die Helligkeitswechselfolgen ergibt sich, daß das ZNS von Chlorophanus das Gesichtsfeld seiner Fazettenaugen in der Ebene der Bewegungsintegration nicht räumlich repräsentiert. Bewegung wird repräsentiert nicht als räumliche Fortbewegung, sondern als nichtlokalisierter Vektor. 相似文献
112.
Paul F. Torrence Erik De Clercq James A. Waters Bernhard Witkop 《Biochemical and biophysical research communications》1975,62(3):658-664
Polylaurusin[poly(L) or “polyformycin B”] forms double-stranded complexes with polycytidylic acid (poly(C)) and with poly(5-bromocytidylic acid) [poly(br5C)] with Tm's of 46.5° (0.2 NaCl, pH 7) and 72.5° (0.15 M NaCl, pH 7), respectively. Both complexes fail to provide antiviral resistance (against vesicular stomatitis virus in primary rabbit kidney cells) or to induce interferon in “superinduced” primary rabbit kidney cells, even though they fulfill all previously recognized requirements for effective interferon inducers. 相似文献
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Fabiola Marín‐Aguilar Ana V. Lechuga‐Vieco Elísabet Alcocer‐Gmez Beatriz Castejn‐Vega Javier Lucas Carlos Garrido Alejandro Peralta‐Garcia Antonio J. Prez‐Pulido Alfonso Varela‐Lpez Jos L. Quiles Bernhard Ryffel Ignacio Flores Pedro Bulln Jesús Ruiz‐Cabello Mario D. Cordero 《Aging cell》2020,19(1)
While NLRP3‐inflammasome has been implicated in cardiovascular diseases, its role in physiological cardiac aging is largely unknown. During aging, many alterations occur in the organism, which are associated with progressive impairment of metabolic pathways related to insulin resistance, autophagy dysfunction, and inflammation. Here, we investigated the molecular mechanisms through which NLRP3 inhibition may attenuate cardiac aging. Ablation of NLRP3‐inflammasome protected mice from age‐related increased insulin sensitivity, reduced IGF‐1 and leptin/adiponectin ratio levels, and reduced cardiac damage with protection of the prolongation of the age‐dependent PR interval, which is associated with atrial fibrillation by cardiovascular aging and reduced telomere shortening. Furthermore, old NLRP3 KO mice showed an inhibition of the PI3K/AKT/mTOR pathway and autophagy improvement, compared with old wild mice and preserved Nampt‐mediated NAD+ levels with increased SIRT1 protein expression. These findings suggest that suppression of NLRP3 prevented many age‐associated changes in the heart, preserved cardiac function of aged mice and increased lifespan. 相似文献
119.
Comparing diversity levels in environmental samples: DNA sequence capture and metabarcoding approaches using 18S and COI genes 总被引:1,自引:0,他引:1
Hendrik Giebner Kathrin Langen Sarah J. Bourlat Sandra Kukowka Christoph Mayer Jonas J. Astrin Bernhard Misof Vera G. Fonseca 《Molecular ecology resources》2020,20(5):1333-1345
Environmental DNA studies targeting multiple taxa using metabarcoding provide remarkable insights into levels of species diversity in any habitat. The main drawbacks are the presence of primer bias and difficulty in identifying rare species. We tested a DNA sequence‐capture method in parallel with the metabarcoding approach to reveal possible advantages of one method over the other. Both approaches were performed using the same eDNA samples and the same 18S and COI regions, followed by high throughput sequencing. Metabarcoded eDNA libraries were PCR amplified with one primer pair from 18S and COI genes. DNA sequence‐capture libraries were enriched with 3,639 baits targeting the same gene regions. We tested amplicon sequence variants (ASVs) and operational taxonomic units (OTUs) in silico approaches for both markers and methods, using for this purpose the metabarcoding data set. ASVs methods uncovered more species for the COI gene, whereas the opposite occurred for the 18S gene, suggesting that clustering reads into OTUs could bias diversity richness especially using 18S with relaxed thresholds. Additionally, metabarcoding and DNA sequence‐capture recovered 80%–90% of the control sample species. DNA sequence‐capture was 8x more expensive, nonetheless it identified 1.5x more species for COI and 13x more genera for 18S than metabarcoding. Both approaches offer reliable results, sharing ca. 40% species and 72% families and retrieve more taxa when nuclear and mitochondrial markers are combined. eDNA metabarcoding is quite well established and low‐cost, whereas DNA‐sequence capture for biodiversity assessment is still in its infancy, is more time‐consuming but provides more taxonomic assignments. 相似文献