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71.
Nuria Garrido M. Dolors Alvarez del Castillo 《The International Journal of Life Cycle Assessment》2007,12(4):252-256
Goal, Scope and Background The objective of the study was to determine the environmental effects of the resuable cup used during a major event (which
took place in Barcelona, Universal Forum of Cultures, 2004), compared with a single-use cup of the same composition (polypropylene)
but with different physical characteristics such as mass, shape and capacity.
Methods To perform the environmental evaluations and the comparison of both types of cups, the SimaPro software developed and marketed
by PRé Consultants was used. The environmental evaluation of the reusable cup was compared with that of a single-use cup using
the LCA methodology [6]. The functional unit used was: ‘Serving 1000 liters of draught beverages’. The objective of the study
was to find the minimum number of cycles the reusable cup has to do so that its environmental impact is smaller than that
of the single-use cup.
Results and Conclusions Taking into account all the hypotheses put forward, the study drew the conclusion that the minimum number of uses of the reusable
cup necessary for it to have a smaller environmental impact than the single-use cup is 10. The contribution of each process
taking part in the entire life cycle of the cups was also studied in detail. In the case of the single-use cup, the most important
contribution to all the impact categories is due to the production of polypropylene and the fabrication of the cup, except
for the heavy metals category where it is due to the management of the waste coming from the cup’s use.
In the case of the reusable cup being used 10 times, the contribution to the different impact categories of the waste generated
by the cup’s use is negligible compared to the contribution of the fabrication and washing processes. In addition, the washing
process is the one which contributes most to the ozone layer depletion, heavy metals and carcinogens categories.
As the number of uses of the reusable cup increases, the contribution to all the environmental impact categories decreases.
However, this reduction is not as significant for the ozone layer depletion, heavy metals and carcinogens categories. This
is due to the washing process and the fact that the electrical consumption associated with it increases with the number of
washings and, consequently, of uses.
Recommendations and Perspectives From the environmental point of view, the reusable cup must be used at least 10 times to have less impact than the single-use
cup. This is mainly due to the higher weight of the reusable cup and, therefore, the greater amount of raw material needed
for its fabrication. If the LCA methodology had been introduced during the design of the reusable cup, its weight would have
been lower. This modification would have resulted in a reduction of the environmental impact associated with the use of the
reusable cup and, consequently, a smaller number of uses would have been necessary to attain the same level of impact as the
single-use cup. 相似文献
72.
73.
Stephen K. Pikesley Annette C. Broderick Daniel Cejudo Michael S. Coyne Matthew H. Godfrey Brendan J. Godley Pedro Lopez Luis Felipe Lpez‐Jurado Sonia Elsy Merino Nuria Varo‐Cruz Matthew J. Witt Lucy A. Hawkes 《Ecography》2015,38(8):803-812
The integration of satellite telemetry, remotely sensed environmental data, and habitat/environmental modelling has provided for a growing understanding of spatial and temporal ecology of species of conservation concern. The Republic of Cape Verde comprises the only substantial rookery for the loggerhead turtle Caretta caretta in the eastern Atlantic. A size related dichotomy in adult foraging patterns has previously been revealed for adult sea turtles from this population with a proportion of adults foraging neritically, whilst the majority forage oceanically. Here we describe observed habitat use and employ ecological niche modelling to identify suitable foraging habitats for animals utilising these two distinct behavioural strategies. We also investigate how these predicted habitat niches may alter under the influence of climate change induced oceanic temperature rises. We further contextualise our niche models with fisheries catch data and knowledge of fisheries ‘hotspots’ to infer threat from fisheries interaction to this population, for animals employing both strategies. Our analysis revealed repeated use of coincident oceanic habitat, over multiple seasons, by all smaller loggerhead turtles, whilst larger neritic foraging turtles occupied continental shelf waters. Modelled habitat niches were spatially distinct, and under the influence of predicted sea surface temperature rises, there was further spatial divergence of suitable habitats. Analysis of fisheries catch data highlighted that the observed and modelled habitats for oceanic and neritic loggerhead turtles could extensively interact with intensive fisheries activity within oceanic and continental shelf waters of northwest Africa. We suggest that the development and enforcement of sustainable management strategies, specifically multi‐national fisheries policy, may begin to address some of these issues; however, these must be flexible and adaptive to accommodate potential range shift for this species. 相似文献
74.
75.
Tor1, Sch9 and PKA downregulation in quiescence rely on Mtl1 to preserve mitochondrial integrity and cell survival 下载免费PDF全文
Venkatraghavan Sundaram Mima I. Petkova Nuria Pujol‐Carrion Jordi Boada Maria Angeles de la Torre‐Ruiz 《Molecular microbiology》2015,97(1):93-109
Here we show that Mtl1, member of the cell wall integrity pathway of Saccharomyces cerevisiae, plays a positive role in chronological life span (CLS). The absence of Mtl1 shortens CLS and causes impairment in the mitochondrial function. This is reflected in a descent in oxygen consumption during the postdiauxic state, an increase in the uncoupled respiration and mitochondrial membrane potential and also a descent in aconitase activity. We demonstrate that all these effects are a consequence of signalling defects suppressed by TOR1 (target of rapamycin) and SCH9 deletion and less efficiently by Protein kinase A (PKA) inactivation. Mtl1 also plays a role in the regulation of both Bcy1 stability and phosphorylation, mainly in response to glucose depletion. In postdiauxic phase and in conditions of glucose depletion, Mtl1 negatively regulates TOR1 function leading to Sch9 inactivation and Bcy1 phosphorylation converging in PKA inhibition. Slt2/Mpk1 kinase partially contributes to Bcy1 phosphorylation, although additional targets are not excluded. Mtl1 links mitochondrial dysfunction with TOR and PKA pathways in quiescence, glucose being the main signalling molecule. 相似文献
76.
Rohini Sidhu Hui Jiang Nicole Y. Farhat Nuria Carrillo-Carrasco Myra Woolery Elizabeth Ottinger Forbes D. Porter Jean E. Schaffer Daniel S. Ory Xuntian Jiang 《Journal of lipid research》2015,56(6):1222-1233
24(S)-hydroxycholesterol [24(S)-HC] is a cholesterol metabolite that is formed almost exclusively in the brain. The concentrations of 24(S)-HC in cerebrospinal fluid (CSF) and/or plasma might be a sensitive marker of altered cholesterol metabolism in the CNS. A highly sensitive 2D-LC-MS/MS assay was developed for the quantification of 24(S)-HC in human plasma and CSF. In the development of an assay for 24(S)-HC in CSF, significant nonspecific binding of 24(S)-HC was observed and resolved with the addition of 2.5% 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) into CSF samples. The sample preparation consists of liquid-liquid extraction with methyl-tert-butyl ether and derivatization with nicotinic acid. Good linearity was observed in a range from 1 to 200 ng/ml and from 0.025 to 5 ng/ml, for plasma and CSF, respectively. Acceptable precision and accuracy were obtained for concentrations over the calibration curve ranges. Stability of 24(S)-HC was reported under a variety of storage conditions. This method has been successfully applied to support a National Institutes of Health-sponsored clinical trial of HP-β-CD in Niemann-Pick type C1 patients, in which 24(S)-HC is used as a pharmacodynamic biomarker. 相似文献
77.
78.
Symptoms induced by transgenic expression of p23 from Citrus tristeza virus in phloem‐associated cells of Mexican lime mimic virus infection without the aberrations accompanying constitutive expression 下载免费PDF全文
Nuria Soler Carmen Fagoaga Carmelo López Pedro Moreno Luis Navarro Ricardo Flores Leandro Peña 《Molecular Plant Pathology》2015,16(4):388-399
Citrus tristeza virus (CTV) is phloem restricted in natural citrus hosts. The 23‐kDa protein (p23) encoded by the virus is an RNA silencing suppressor and a pathogenicity determinant. The expression of p23, or its N‐terminal 157‐amino‐acid fragment comprising the zinc finger and flanking basic motifs, driven by the constitutive 35S promoter of cauliflower mosaic virus, induces CTV‐like symptoms and other aberrations in transgenic citrus. To better define the role of p23 in CTV pathogenesis, we compared the phenotypes of Mexican lime transformed with p23‐derived transgenes from the severe T36 and mild T317 CTV isolates under the control of the phloem‐specific promoter from Commelina yellow mottle virus (CoYMV) or the 35S promoter. Expression of the constructs restricted to the phloem induced a phenotype resembling CTV‐specific symptoms (vein clearing and necrosis, and stem pitting), but not the non‐specific aberrations (such as mature leaf epinasty and yellow pinpoints, growth cessation and apical necrosis) observed when p23 was ectopically expressed. Furthermore, vein necrosis and stem pitting in Mexican lime appeared to be specifically associated with p23 from T36. Phloem‐specific accumulation of the p23Δ158–209(T36) fragment was sufficient to induce the same anomalies, indicating that the region comprising the N‐terminal 157 amino acids of p23 is responsible (at least in part) for the vein clearing, stem pitting and, possibly, vein corking in this host. 相似文献
79.
Gonzalez-Montalban N Makarava N Ostapchenko VG Savtchenk R Alexeeva I Rohwer RG Baskakov IV 《PLoS pathogens》2011,7(2):e1001277
Protein misfolding cyclic amplification (PMCA) provides faithful replication of mammalian prions in vitro and has numerous applications in prion research. However, the low efficiency of conversion of PrP(C) into PrP(Sc) in PMCA limits the applicability of PMCA for many uses including structural studies of infectious prions. It also implies that only a small sub-fraction of PrP(C) may be available for conversion. Here we show that the yield, rate, and robustness of prion conversion and the sensitivity of prion detection are significantly improved by a simple modification of the PMCA format. Conducting PMCA reactions in the presence of Teflon beads (PMCAb) increased the conversion of PrP(C) into PrP(Sc) from ~10% to up to 100%. In PMCAb, a single 24-hour round consistently amplified PrP(Sc) by 600-700-fold. Furthermore, the sensitivity of prion detection in one round (24 hours) increased by 2-3 orders of magnitude. Using serial PMCAb, a 1012-fold dilution of scrapie brain material could be amplified to the level detectible by Western blotting in 3 rounds (72 hours). The improvements in amplification efficiency were observed for the commonly used hamster 263K strain and for the synthetic strain SSLOW that otherwise amplifies poorly in PMCA. The increase in the amplification efficiency did not come at the expense of prion replication specificity. The current study demonstrates that poor conversion efficiencies observed previously have not been due to the scarcity of a sub-fraction of PrP(C) susceptible to conversion nor due to limited concentrations of essential cellular cofactors required for conversion. The new PMCAb format offers immediate practical benefits and opens new avenues for developing fast ultrasensitive assays and for producing abundant quantities of PrP(Sc)in vitro. 相似文献
80.