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141.
An IL-13 Promoter Polymorphism Associated with Liver Fibrosis in Patients with Schistosoma japonicum
142.
Eva C. Schulte Maria Kousi Perciliz L. Tan Erik Tilch Franziska Knauf Peter Lichtner Claudia Trenkwalder Birgit Högl Birgit Frauscher Klaus Berger Ingo Fietze Magdolna Hornyak Wolfgang H. Oertel Cornelius G. Bachmann Alexander Zimprich Annette Peters Christian Gieger Thomas Meitinger Bertram Müller-Myhsok Nicholas Katsanis Juliane Winkelmann 《American journal of human genetics》2014
143.
Modulation of mesenchymal stromal cell characteristics by microcarrier culture in bioreactors
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144.
Merz Felicitas Müller Mareike Taucher-Scholz Gisela Rödel Franz Stöcker Horst Schopow Kosta Laprell Laura Dehghani Faramarz Durante Marco Bechmann Ingo 《Radiation and environmental biophysics》2010,49(3):457-462
The aim of this interdisciplinary project is to establish slice culture preparations from rodents and humans as a new model
system for studying effects of X-rays and heavy ions within normal and tumor tissues. The advantage of such slice cultures
relies on the conservation of an organotypic environment, the easy treatment and observation by live-imaging microscopy, and
the independence from genetic immortalization strategies used to generate cell lines. Rat brains as well as human tumors were
cut into 300-μm-thick sections and cultivated in an incubator in a humidified atmosphere at 37°C. This is realized by a membrane-based
culture system with a liquid–air interface. With this system, it is possible to keep rodent slices viable for several months.
Human brain tumor slices remained vital for at least 21 days. Slices were irradiated with X-rays at the radiation facility
of the University Hospital in Frankfurt/Main at doses up to 40 Gy. Heavy ion irradiations were performed at GSI (Darmstadt)
with different ions, energies, and doses. The irradiated slices were analyzed by 3D-confocal microscopy following immunostaining
for DNA damage, microglia, and proliferation markers. The phosphorylated histone γH2AX proved to be suitable for the detection
of ion traversals in this system. 相似文献
145.
146.
Individuals providing misleading information to conspecifics may benefit from deception at the receiver's expense. A recent
study (Plath et al., Curr Biol 18:1138–1141, 2008c) suggested that male Atlantic mollies (Poecilia mexicana) deceive rival males about their preferred mate. Here, we contrasted potentially deceptive behavior in surface-dwelling P. mexicana males to males of the cave form of that species (the cave molly). Unlike many other cavefishes, cave mollies have retained
functional eyes and readily respond to visual stimuli. Males could interact freely with two females (large and small), and
an audience male was visually presented during the second part of the tests. When observed during mate choice, males reduced
their mating activity, but this reduction was significantly weaker in cave mollies. Overall, the expression of mating preferences
(determined through frequencies of nipping and thrusting) declined in front of an audience; again, this effect was significantly
weaker in the cave form. Reduced sexual activity and reduced expression of mating preferences can be interpreted as an attempt
of the focal male to avoid unintended interception of information by the rival male. Surface but not cave molly males directed
their first sexual interaction (when being observed by the rival male) towards the initially non-preferred female, suggesting
that surface-dwelling males deceive rival males about their mating preferences. Deception by the focal males may be an adaptation
to avoid sperm competition, since other males in their social environment may use public information and copy the focal male's
mate choice. It seems that sending deceptive signals is evolutionarily regressed in the cave molly, since mate choice copying
is unlikely to occur under naturally dark conditions, and also the potential to deceive rivals about mating preferences is
probably very limited. 相似文献
147.
Nikolaus Bresgen Heidi Jaksch Heide Lacher Ingo Ohlenschläger Koji Uchida Peter M. Eckl 《Free radical biology & medicine》2010,48(10):1347-1357
Previously, we have demonstrated an apoptosis-inducing activity of an acidic, H-chain-rich isoferritin secreted from primary rat hepatocytes in vitro. Because this proapoptotic property may be responsible for the growth-inhibitory and immunosuppressive effects described for certain ferritin species, we aimed to address the mechanism by which ferritin can trigger cell death. Suggesting a pivotal role for iron, iron chelation by desferrioxamine significantly abrogates ferritin-mediated apoptosis and necrosis in primary rat hepatocytes and substantially lowers the extent of protein modification by 4-hydroxynonenal (HNE)—a major lipid peroxidation (LPO) product. Furthermore, supplementing the cultures with the radical-scavenging compound trolox also provided significant protection from ferritin-mediated apoptosis. Moreover, a significant increase in micronucleated cells upon exposure to ferritin indicates that ferritin also introduces damage to DNA. Based on these observations we therefore propose that endocytosis of extracellular ferritin increases the level of free ferrous iron in the lysosomal compartment, promoting Fenton chemistry-based oxidative stress involving LPO and increased lysosomal membrane permeability. Subsequently, the release of reactive lysosomal content leads to cellular damage, in particular modification of protein and DNA induced by HNE and other reactive aldehydic LPO products. Together, these effects will trigger apoptosis and necrosis based on the upregulation of p53, increased mitochondrial membrane permeability, and proapoptotic Fas signaling as described recently. In conclusion, based on their iron-storing ability, secreted acidic isoferritins may act as soluble mediators of oxidative stress under certain physiological and pathophysiological conditions. 相似文献
148.
Pablo M. Vergara Ingo J. Hahn Horacio Zeballos Juan J. Armesto 《Ecological Research》2010,25(3):683-690
Conservation of forest birds in fragmented landscapes requires not only determining the critical patch characteristics influencing
local population persistence but also identifying patch networks providing connectivity and suitable habitat conditions necessary
to ensure regional persistence. In this study, we assessed the importance of patch attributes, patch connectivity, and network
components (i.e., groups of interconnected patches) in explaining the occupancy pattern of the Thorn-tailed Rayadito (Aphrastura spinicauda), a forest bird species of central Chile. Using a daily movement threshold distance, we identified a total of 16 network
components of sclerophyllous forest within the study area. Among those components, patch area and vegetation structure-composition
were important predictors of patch occupancy. However, the inclusion of patch connectivity and component size (i.e., the area
of a network component) into the models greatly increases the models’ accuracy and parsimony. Using the best-fitted model,
a total of 33 patches were predicted to be occupied by rayaditos within the study area, but such occupied patches were distributed
in only six network components. These results suggest that persistence of rayaditos in central Chile requires the maintenance
of large single patches and patch networks providing habitat and connectivity. 相似文献
149.
Nicole Schreiber Notburga Gierlinger Norbert Pütz Peter Fratzl Christoph Neinhuis Ingo Burgert 《The Plant journal : for cell and molecular biology》2010,61(5):854-861
Root contraction has been described for many species within the plant kingdom for over a century, and many suggestions have been made for mechanisms behind these contractions. To move the foliage buds deeper into the soil, the proximal part of the storage root of Trifolium pratense contracts by up to 30%. Anatomical studies have shown undeformed fibres next to strongly deformed tissues. Raman imaging revealed that these fibres are chemically and structurally very similar to poplar (Populus) tension wood fibres, which are known to generate high tensile stresses and bend leaning stems or branches upright. Analogously, an almost pure cellulosic layer is laid down in the lumen of certain root fibres, on a thin lignified secondary cell wall layer. To reveal its stress generation capacities, the thick cellulosic layer, reminiscent of a gelatinous layer (G‐layer) in tension wood, was selectively removed by enzymatic treatment. A substantial change in the dimensions of the isolated wood fibre bundles was observed. This high stress relaxation indicates the presence of high tensile stress for root contraction. These findings indicate a mechanism of root contraction in T. pratense (red clover) actuated via tension wood fibres, which follows the same principle known for poplar tension wood. 相似文献
150.
Romy F.J. Janser Ranjith K. Meka Zack E. Bryant Enoch A. Adogla Elizabeth K. Vogel Jaimie L. Wharton Cynthia M. Tilley Catherine N. Kaminski Seth L. Ferrey Severine Van slambrouck Wim F.A. Steelant Ingo Janser 《Bioorganic & medicinal chemistry letters》2010,20(6):1848-1850
A series of ethacrynic acid analogues, lacking the α,β-unsaturated carbonyl unit, was synthesized and subsequently evaluated for their ability to inhibit the migration of human breast cancer cells, MCF-7/AZ. Several of the analogues were already active in the low micromolar range, whereas ethacrynic acid itself shows no potential to inhibit the migration of these cancer cells. Preliminary studies show that the presence of one or more methoxy groups at the phenyl ring of ethacrynic acid is important in order for the ethacrynic acid analogues to demonstrate an inhibitory effect on the migration. 相似文献