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991.
Lukas Habernig Filomena Broeskamp Andreas Aufschnaiter Jutta Diessl Carlotta Peselj Elisabeth Urbauer Tobias Eisenberg Ana de Ory Sabrina Büttner 《PLoS genetics》2021,17(11)
The capacity of a cell to maintain proteostasis progressively declines during aging. Virtually all age-associated neurodegenerative disorders associated with aggregation of neurotoxic proteins are linked to defects in the cellular proteostasis network, including insufficient lysosomal hydrolysis. Here, we report that proteotoxicity in yeast and Drosophila models for Parkinson’s disease can be prevented by increasing the bioavailability of Ca2+, which adjusts intracellular Ca2+ handling and boosts lysosomal proteolysis. Heterologous expression of human α-synuclein (αSyn), a protein critically linked to Parkinson’s disease, selectively increases total cellular Ca2+ content, while the levels of manganese and iron remain unchanged. Disrupted Ca2+ homeostasis results in inhibition of the lysosomal protease cathepsin D and triggers premature cellular and organismal death. External administration of Ca2+ reduces αSyn oligomerization, stimulates cathepsin D activity and in consequence restores survival, which critically depends on the Ca2+/calmodulin-dependent phosphatase calcineurin. In flies, increasing the availability of Ca2+ discloses a neuroprotective role of αSyn upon manganese overload. In sum, we establish a molecular interplay between cathepsin D and calcineurin that can be activated by Ca2+ administration to counteract αSyn proteotoxicity. 相似文献
992.
Elena Motivans vara Valentin tefan Esther Sossai Reinart Feldmann Dianne Joy Aguilon Anna Bontsutsnaja Anna EVojtk Isabel C. Kilian Piret Lang Marilin Mtlep Elisabeth Prangel MariLiis Viljur Tiffany M. Knight Lena Neuenkamp 《Ecology and evolution》2021,11(23):16909
In the face of global pollinator decline, extensively managed grasslands play an important role in supporting stable pollinator communities. However, different types of extensive management may promote particular plant species and thus particular functional traits. As the functional traits of flowering plant species (e.g., flower size and shape) in a habitat help determine the identity and frequency of pollinator visitors, they can also influence the structures of plant−pollinator interaction networks (i.e., pollination networks). The aim of this study was to examine how the type of low‐intensity traditional management influences plant and pollinator composition, the structure of plant−pollinator interactions, and their mediation by floral and insect functional traits. Specifically, we compared mown wooded meadows to grazed alvar pastures in western Estonia. We found that both management types fostered equal diversity of plants and pollinators, and overlapping, though still distinct, plant and pollinator compositions. Wooded meadow pollination networks had significantly higher connectance and specialization, while alvar pasture networks achieved higher interaction diversity at a standardized sampling of interactions. Pollinators with small body sizes and short proboscis lengths were more specialized in their preference for particular plant species and the specialization of individual pollinators was higher in alvar pastures than in wooded meadows. All in all, the two management types promoted diverse plant and pollinator communities, which enabled the development of equally even and nested pollination networks. The same generalist plant and pollinator species were important for the pollination networks of both wooded meadows and alvar pastures; however, they were complemented by management‐specific species, which accounted for differences in network structure. Therefore, the implementation of both management types in the same landscape helps to maintain high species and interaction diversity. 相似文献
993.
Yoshiaki Nakagawa Martin Sadilek Elisabeth Lehmberg Rafael Herrmann Revital Herrmann Haim Moskowitz Young Moo Lee Beth Ann Thomas Ryo Shimizu Masataka Kuroda A. Daniel Jones Bruce D. Hammock 《Archives of insect biochemistry and physiology》1998,38(2):53-65
As recombinant viruses expressing scorpion toxins are moving closer toward the market, it is important to obtain large amounts of pure toxin for biochemical characterization and the evaluation of biological activity in nontarget organisms. In the past, we purified a large amount of Androctonus australis anti-insect toxin (AaIT) present in the venom of A. australis with an analytical reversed-phase column by repeated runs of crude sample. We now report 20 times improved efficiency and speed of the purification by employing a preparative reversed-phase column. In just two consecutive HPLC steps, almost 1 mg of AaIT was obtained from 70 mg crude venom. Furthermore, additional AaIT was obtained from side fractions in a second HPLC run. Recently discovered insect selective toxin, AaIT5, was isolated simultaneously from the same venom batch. It shows different biological toxicity symptoms than the known excitatory and depressant insect toxins. AaIT5 gave 100% mortality with a dose of less than 1.3 μg against fourth-instar tobacco budworms Heliothis virescens 24 h after injection. During the purification process, we implemented mass spectrometry in addition to bioassays to monitor the presence of AaIT and AaIT5 in the HPLC fractions. Mass spectrometric screening can unambiguously follow the purification process and can greatly facilitate and expedite the downstream purification of AaIT and AaIT5 eliminating the number of bioassays required. Further, electrospray ionization was compared with matrix-assisted desorption/ionization and evaluated as a method of choice for mass spectrometric characterization of fractions from the venom purification for it provided higher mass accuracy and relative quantitation capability. Molecular models were built for AaIT5, excitatory toxin AaIT4, and depressant toxin LqhIT2. Three-dimensional structure of AaIT5 was compared with structures of the other two toxins, suggesting that AaIT5 is similar to depressant toxins. Arch. Insect Biochem. Physiol. 38:53–65, 1998. © 1998 Wiley-Liss, Inc. 相似文献
994.
Jenneke Klein-Nulend Jan Roelofsen Cornelis M. Semeins Antonius L. J. J. Bronckers Elisabeth H. Burger 《Journal of cellular physiology》1997,170(2):174-181
We have shown earlier that mechanical stimulation by intermittent hydrostatic compression (IHC) promotes alkaline phosphatase and procollagen type I gene expression in calvarial bone cells. The bone matrix glycoprotein osteopontin (OPN) is considered to be important in bone matrix metabolism and cell-matrix interactions, but its role is unknown. Here we examined the effects of IHC (13 kPa) on OPN mRNA expression and synthesis in primary calvarial cell cultures and the osteoblast-like cell line MC3T3-E1. OPN mRNA expression declined during control culture of primary calvarial cells, but not MC3T3-E1 cells. IHC upregulated OPN mRNA expression in late released osteoblastic cell cultures, but not in early released osteoprogenitor-like cells. Also, in both proliferating and differentiating MC3T3-E1 cells, OPN mRNA expression and synthesis were enhanced by IHC, differentiating cells being more responsive than proliferating cells. These results suggest a role for OPN in the reaction of bone cells to mechanical stimuli. The severe loss of OPN expression in primary bone cells cultured without mechanical stimulation suggests that disuse conditions down-regulate the differentiated osteoblastic phenotype. J. Cell. Physiol. 170:174–181, 1997. © 1997 Wiley-Liss, Inc. 相似文献
995.
Placental‐Specific Overexpression of sFlt‐1 Alters Trophoblast Differentiation and Nutrient Transporter Expression in an IUGR Mouse Model 下载免费PDF全文
996.
997.
Teija?AleniusEmail authorView authors OrcID profile Teemu?M?kk?nen Elisabeth?Holmqvist Antti?Ojala 《Vegetation History and Archaeobotany》2017,26(5):469-486
Two high-resolution pollen and charcoal analyses were constructed from sediments obtained from a small bay in eastern Finland in order to gain information on human activity during the Neolithic Stone Age, 5200–1800 bc. We used measurements of loss on ignition (LOI), magnetic susceptibility and geochemical analyses to describe the sedimentological characteristics. Palaeomagnetic dating and measurements of 137Cs-activity were supported by 14C-datings. The analyses revealed human activity between 4400 and 3200 bc, which is synchronous with archaeological cultures defined through different stages of Comb Ware pottery types and Middle Neolithic pottery types with asbestos as a primary temper. Direct evidence of Hordeum cultivation was dated to 4040–3930 cal bc. According to the pollen data, more significant effort was put into the production of fibres from hemp and lime than the actual cultivation of food. 相似文献
998.
Elisabeth Keijzer 《The International Journal of Life Cycle Assessment》2017,22(5):715-730
Purpose
Although the funeral market is propagating new ‘green’ alternatives and exploring innovative techniques like resomation, very little is known about the environmental impact of funerals. This research aimed to develop a benchmark of funerals, by quantifying the environmental impacts of the most common funeral techniques, i.e. burial and cremation, by identifying where the main impacts originate from and by comparing these impacts to impacts of other activities during a person’s life.Methods
The environmental impacts of funerals were analysed by means of a life cycle assessment (LCA), based on Dutch company information, literature and expert judgements. The results were analysed per impact category but also on an aggregated level by means of shadow prices. Two sensitivity analyses were performed: one examined the high impact of cotton in funeral coffins; the other checked the results by means of another weighting method.Results and discussion
The results showed no significant difference between the two funeral techniques in five impact categories. Burial has the lowest impact in more than half of the categories, but its impact is many times higher in the two most differing categories than for cremation. The total shadow price of burial is about 30 % higher than the shadow price of cremation, but the main cause for this difference is a highly debated category, namely land use. If the results would be considered without the shadow prices of land impact categories, burial would score 25 % lower than cremation. These results are representing average practise and may deviate on certain aspects for other countries, but as a starting point for further studies, this benchmark is well applicable.Conclusions and recommendations
This study delivered an environmental benchmark of funerals and insights in the impacts of the individual processes, which can be used in further assessment of ’green’ funeral options. The benchmark results show that the environmental impact of funerals is largely determined by secondary processes and that the total impact can be quite small in comparison to other human activities. Besides these environmental insights, it is important to take into account social, cultural, climatic, local, economical and ethical arguments before changing policies or giving recommendations.999.
1000.
QTL mapping of Fusarium head blight resistance in three related durum wheat populations 总被引:2,自引:0,他引:2
Noemie Prat Camille Guilbert Ursa Prah Elisabeth Wachter Barbara Steiner Thierry Langin Olivier Robert Hermann Buerstmayr 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2017,130(1):13-27