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991.
Marco Mengarelli Sabrina Neugebauer Matthias Finkbeiner Michele Germani Patrizia Buttol Francesca Reale 《The International Journal of Life Cycle Assessment》2017,22(8):1288-1301
Purpose
End-of-life (EoL) modelling in life cycle assessment has already been broadly discussed within several studies. However, no consensus has been achieved on how to model recycling in LCA, even though several approaches have been developed. Within this paper, results arising from the application of two new EoL formulas, the product environmental footprint (PEF) and the multi-recycling-approach (MRA) ones, are compared and discussed. Both formulas consider multiple EoL scenarios such as recycling, incineration and landfill.Methods
The PEF formula has been developed within the PEF programme whose intent is to define a harmonized methodology to evaluate the environmental performance of products. The formula is based on a 50:50 allocation approach, as burdens and benefits associated with recycling are accounted for a 50% rate. The MRA formula has been developed to change focus from products to materials. Recycling cycles and material losses over time are considered with reference to material pools. Allocation between systems is no longer needed, as the actual number of potential life cycles for a certain material is included in the calculation. Both the approaches have been tested within two case studies.Results and discussion
Methodological differences could thereof be determined, as well as applicability concerns, due to the type of data required for each formula. As far as the environmental performance is concerned, impacts delivered by MRA are lower than those delivered by PEF for aluminium, while the opposite happens for plastic and rubber due to the higher share of energy recovery accounted in PEF formula. Stainless steel impacts are almost the same.Conclusions and recommendations
The application of the two formulas provides some inputs for the EoL dilemma in LCA. The use of a wider perspective, better reflecting material properties all over the material life cycle, is of substantial importance to properly represent recycling situations. In MRA, such properties are treated and less data are required compared to the PEF formula. On the contrary, the PEF model better accommodates the modelling of products whose materials, at end of life, can undertake the route of recycling or recovery (or landfill), depending on country-specific EoL management practices. However, its application requires more data.992.
993.
Zambarlal Bhujabal Åsa B Birgisdottir Eva Sjøttem Hanne B Brenne Aud Øvervatn Sabrina Habisov Vladimir Kirkin Trond Lamark Terje Johansen 《EMBO reports》2017,18(6):947-961
Mitophagy, the selective removal of damaged or excess mitochondria by autophagy, is an important process in cellular homeostasis. The outer mitochondrial membrane (OMM) proteins NIX, BNIP3, FUNDC1, and Bcl2‐L13 recruit ATG8 proteins (LC3/GABARAP) to mitochondria during mitophagy. FKBP8 (also known as FKBP38), a unique member of the FK506‐binding protein (FKBP) family, is similarly anchored in the OMM and acts as a multifunctional adaptor with anti‐apoptotic activity. In a yeast two‐hybrid screen, we identified FKBP8 as an ATG8‐interacting protein. Here, we map an N‐terminal LC3‐interacting region (LIR) motif in FKBP8 that binds strongly to LC3A both in vitro and in vivo. FKBP8 efficiently recruits lipidated LC3A to damaged mitochondria in a LIR‐dependent manner. The mitophagy receptors BNIP3 and NIX in contrast are unable to mediate an efficient recruitment of LC3A even after mitochondrial damage. Co‐expression of FKBP8 with LC3A profoundly induces Parkin‐independent mitophagy. Strikingly, even when acting as a mitophagy receptor, FKBP8 avoids degradation by escaping from mitochondria. In summary, this study identifies novel roles for FKBP8 and LC3A, which act together to induce mitophagy. 相似文献
994.
Sabrina Ceeraz Susan K. Eszterhas Petra A. Sergent David A. Armstrong Alix Ashare Thomas Broughton Li Wang Dov Pechenick Christopher M. Burns Randolph J. Noelle Matthew P. Vincenti Roy A. Fava 《Arthritis research & therapy》2017,19(1):270
Background
In addition to activated T cells, the immune checkpoint inhibitor “V domain-containing Ig suppressor of T-cell activation” (VISTA) is expressed by myeloid cell types, including macrophages and neutrophils. The importance of VISTA expression by myeloid cells to antibody-induced arthritis and its potential for relevance in human disease was evaluated.Methods
VISTA was immunolocalized in normal and arthritic human synovial tissue sections and synovial tissue lysates were subjected to western blot analysis. The collagen antibody-induced arthritis model (CAIA) was performed with DBA/1 J mice treated with antibodies against VISTA and with VISTA-deficient mice (V-KO). Total mRNA from arthritic joints, spleens, and cultured macrophages was analyzed with NanoString arrays. Cytokines secreted by splenic inflammatory macrophages were determined. In-vitro chemotaxis and signal transduction assays were performed with cultured macrophages.Results
VISTA protein was localized to synovial membrane cells, neutrophils, and scattered cells in lymphocyte-rich foci and was detected by western blot analysis in normal synovium and synovium from rheumatoid arthritis patients. Deficiency of VISTA or treatment of mice with anti-VISTA monoclonal antibodies attenuated CAIA. Joint damage and MMP-3 expression were significantly reduced in V-KO mice. Surface expression of C5a receptor was reduced on monocytes, neutrophils, and cultured macrophages from V-KO. Upon Fc receptor engagement in vitro, gene expression by V-KO macrophages was altered profoundly compared to WT, including a significant induction of IL-1 receptor antagonist (IL1rn).Conclusions
VISTA expression supports immune-complex inflammation in CAIA and VISTA is expressed in human synovium. VISTA supports optimal responses to C5a and modulates macrophage responses to immune complexes.995.
996.
The iCLIP and eCLIP techniques facilitate the detection of protein–RNA interaction sites at high resolution, based on diagnostic events at crosslink sites. However, previous methods do not explicitly model the specifics of iCLIP and eCLIP truncation patterns and possible biases. We developed PureCLIP (https://github.com/skrakau/PureCLIP), a hidden Markov model based approach, which simultaneously performs peak-calling and individual crosslink site detection. It explicitly incorporates a non-specific background signal and, for the first time, non-specific sequence biases. On both simulated and real data, PureCLIP is more accurate in calling crosslink sites than other state-of-the-art methods and has a higher agreement across replicates. 相似文献
997.
Shinichi Matsumoto Shilpa Goel Sabrina Qualley D. Michael Strong Jo Anna Reems 《Cell and tissue banking》2003,4(2-4):85-93
Once human islets are isolated, they are typically transplanted into type 1 diabetic recipients within 2 h of isolation. This time restriction makes it difficult for patients to travel from distant locations to receive an islet transplant and it also makes it difficult to complete pre-release quality control assessments (i.e., endotoxin and gram stain) before the expiration of the islet product. Therefore, there were two goals for this study. The first was to measure the stability of islets after a 24 h culture period using CMRL media 1066 (CMRL) supplemented with either fetal bovine serum (FBS); albumin or insulin transferrin and selenium (ITS). The second was to determine the impact of cell concentration and media depth on islet stability. The results of the study indicated that culture recoveries at 37 °C with CMRL + ITS (also known as Memphis media) were higher (64.1 ± 8.3%) than with CMRL supplemented with FBS (38.7 ± 9.7%) or albumin (47.6 ± 8.2%) and that post-culture islet viabilities, post-culture purities and stimulation indexes (SIs) were comparable. In the second series of experiments, the results showed that islets recoveries and SIs in cultures with low islet concentrations (300 IE/ml) were significantly better than cultures at high islet concentrations (1500 IE/ml). Additionally, at a shallow media depth (1.4 vs. 7 mm of media) the SI of the islets improved, and this effect was independent of the additive (i.e., FBS, albumin and ITS). 相似文献
998.
Anthony J. Otsuka Pratumtip Boontrakulpoontawee Natalie Rebeiz Marc Domanus Dawn Otsuka Nena Velamparampil Sabrina Chan Marshall Vande Wyngaerde Sarah Campagna Andrea Cox 《Developmental neurobiology》2002,50(4):333-349
Conventional ankyrins are cortical cytoskeletal proteins that form an ankyrin‐spectrin meshwork underlying the plasma membrane. We report here the unusual structure of a novel ankyrin (AO13 ankyrin, 775,369 Da, 6994 aa, pI = 4.45) that is required for proper axonal guidance in Caenorhabditis elegans. AO13 ankyrin contains the ANK repeat and spectrin‐binding domains found in other ankyrins, but differs from all others in that the acidic carboxyl region contains six blocks of serine/threonine/glutamic acid/proline rich (STEP) repeats separated by seven hydrophobic domains. The STEP repeat blocks are composed primarily of sequences related to ETTTTTTVTREHFEPED(E/D)XnVVESEEYSASGSPVPSE (E/K)DVE(H/R)VI, and the hydrophobic domains contain sequences related to PESGEESDGEGFGSKVLGFAKK[AGMVAGGVVAAPVALAAVGA]KAAYDALKKDDDEE, which includes a potential transmembrane domain (in brackets). Recombinant protein fragments of AO13 ankyrin were used to prepare polyclonal antisera against the spectrin‐binding domain (AO271 Ab), the conventional ankyrin regulatory domain (AO280 Ab), the AO13 ankyrin STEP domain (AO346 Ab), the AO13 ankyrin STEP + hydrophobic domain (AO289 Ab), and against two carboxyl terminal domain fragments (AO263 Ab and AO327 Ab). Western blot analysis with these Ab probes demonstrated multiple protein isoforms. By immunofluorescence microscopy, the antispectrin‐binding and regulatory domain (AO271 and AO280) antibodies recognized many cell types, including neurons, and stained the junctions between cells. The AO13 ankyrin‐specific (AO289 and AO346) antibodies showed a neurally restricted pattern, staining nerve processes and the periphery of neural cell bodies. These results are consistent with a role for AO13 ankyrin in neural development. © 2002 Wiley Periodicals, Inc. J Neurobiol 50: 333–349, 2002; DOI 10.1002/neu.10036 相似文献
999.
Sabrina Spatari Michael Betz Harald Florin Martin Baitz Michael Faltenbacher 《The International Journal of Life Cycle Assessment》2001,6(2):81-84
The growing availability of software tools has increased the speed of generating LCA studies. Databases and visual tools for
constructing material balance modules greatly facilitate the process of analyzing the environmental aspects of product systems
over their life cycle. A robust software tool, containing a large LCI dataset and functions for performing LCIA and sensitivity
analysis will allow companies and LCA practitioners to conduct systems analyses efficiently and reliably. This paper discusses
how the GaBi 3 software tool can be used to perform LCA and Life Cycle Engineering (LCE), a methodology that combines life
cycle economic, environmental, and technology assessment. The paper highlights important attributes of LCA software tools,
including high quality, well-documented data, transparency in modeling, and data analysis functionality. An example of a regional
power grid mix model is used to illustrate the versatility of GaBi 3. 相似文献