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41.
Franc García Xavi Schelling Julen Castellano Andrs Martín-García Francesc Pla Jairo Vzquez-Guerrero 《Biology of sport / Institute of Sport》2022,39(2):237
The purpose of this study was to compare physical demands during the most demanding scenarios (MDS) of different training sessions and official matches in professional basketball players across playing positions. Thirteen professional basketball players were monitored over a 9-week competitive season using a local positioning system. Peak physical demands included total distance, distance covered at > 18 km·h-1, distance and number of accelerations (≥ 2 m∙s-2) and decelerations (≤ -2 m∙s-2) over a 60-second epoch. Analysis of variance for repeated measures, Bonferroni post-hoc tests and standardised Cohen’s effect size (ES) were calculated. Overall, almost all physical demands during the MDS of training were lower (-6.2% to -35.4%) compared to official matches. The only variable that surpassed competition demands was distance covered at > 18 km·h-1, which presented moderate (ES = 0.61, p = 0.01) and small (ES = 0.48, p > 0.05) increases during training sessions four and three days before a competition, respectively. Conversely, the two previous practices before match day presented trivial to very large decreases (ES = 0.09–2.66) in all physical demands. Furthermore, centres achieved the lowest peak value in total distance covered during matches, forwards completed the greatest peak distance at > 18 km·h-1, and guards performed the greatest distance and number of high-intensity accelerations and decelerations. In conclusion, physical demands during the MDS of different training sessions across the microcycle failed to match or surpass peak values during official matches, which should be considered when prescribing a training process intended to optimise the MDS of match play. 相似文献
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Andreas Ciroth Marcel Hagelüken Guido W. Sonnemann Francesc Castells Günter Fleischer 《The International Journal of Life Cycle Assessment》2002,7(5):295-300
Goal and Background Geographical and technological differences in Life Cycle Inventory data are an important source for uncertainty in the result
of Life Cycle Assessments. Knowledge on their impact on the result of an LCA is scarce, and also knowledge on how to manage
them in an LCA case study.
Objective Goal of this paper is to explore these differences for municipal solid waste incinerator plants, and to develop recommendations
for managing technological and geographical differences.
Methodology The paper provides a definition of technological and geographical differences, and analyses their possible impacts. In a case
study, the differences are caused intentionally in ‘games’, by virtually transplanting incineration plants to a different
location and by changing parameters such as the composition of the waste input incinerated. The games are performed by using
a modular model for municipal solid waste incinerator plants. In each case, an LCA including an Impact Assessment is calculated
to trace the impact of these changes, and the results are compared.
Conclusions The conclusions of the paper are two-fold: (1) reduce the differences in inventory data where their impact on the result is
high; where it is possible reducing them to a great extent, and the effort for performing the change acceptable; in the case
of incineration plants: Adapt the flue gas treatment, especially a possible DeNOx step, to the real conditions; (2) make use
of modular process models that allow adapting plant parameters to better meet real conditions, but be aware of possible modelling
errors. The paper invites the scientific community to validate the model used for a waste incinerator plant, and suggest putting
up similar models for other processes, preferably those of similar relevance for Life Cycle Inventories. 相似文献
45.
MOTIVATION: The advent of genomics yields thousands of reading frames in search of function. Identification of conserved functional motifs in protein sequences can be helpful for function prediction. RESULTS: A database and a classification of reported DNA-binding protein motifs has been designed. A program ('TranScout') has been developed for the detection and evaluation of conserved motifs in prokaryotic and eukaryotic sequences of proteins with a gene regulatory function. The efficiency of the program is shown in a benchmark against a database obtained from SWISS-PROT without the protein sequences used to train the program. All motifs were detected with a mean average sensitivity of 0.98 and a mean average specificity of 0.92. AVAILABILITY: The program is freely available for use on the internet at http://luz.uab.es/transcout/. The user can find additional information at this site. 相似文献
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Arolas JL Bronsoms S Lorenzo J Aviles FX Chang JY Ventura S 《The Journal of biological chemistry》2004,279(36):37261-37270
The oxidative folding and reductive unfolding pathways of leech carboxypeptidase inhibitor (LCI; four disulfides) have been characterized in this work by structural and kinetic analysis of the acid-trapped folding intermediates. The oxidative folding of reduced and denatured LCI proceeds rapidly through a sequential flow of 1-, 2-, 3-, and 4-disulfide (scrambled) species to reach the native form. Folding intermediates of LCI comprise two predominant 3-disulfide species (designated as III-A and III-B) and a heterogeneous population of scrambled isomers that consecutively accumulate along the folding reaction. Our study reveals that forms III-A and III-B exclusively contain native disulfide bonds and correspond to stable and partially structured species that interconvert, reaching an equilibrium prior to the formation of the scrambled isomers. Given that these intermediates act as kinetic traps during the oxidative folding, their accumulation is prevented when they are destabilized, thus leading to a significant acceleration of the folding kinetics. III-A and III-B forms appear to have both native disulfides bonds and free thiols similarly protected from the solvent; major structural rearrangements through the formation of scrambled isomers are required to render native LCI. The reductive unfolding pathway of LCI undergoes an apparent all-or-none mechanism, although low amounts of intermediates III-A and III-B can be detected, suggesting differences in protection against reduction among the disulfide bonds. The characterization of III-A and III-B forms shows that the former intermediate structurally and functionally resembles native LCI, whereas the III-B form bears more resemblance to scrambled isomers. 相似文献
48.
Importance of transient storage zones for ammonium and phosphate retention in a sandy-bottom Mediterranean stream 总被引:3,自引:0,他引:3
1. The ability of hyporheic sediments to exchange water and retain ammonium and phosphate in the Riera Major stream ,North-East Spain, under different discharge conditions was measured by conducting short-term nutrient and chloride additions. 2. The mean exchange coefficients from free-flowing water to the storage zone (k1) and vice versa (k2) were 0.82 × 10–4 s??1 and 7 × 10??3 s??1, respectively. The ratio of storage zone cross-sectional area to stream cross-sectional area (AS/A) averaged 2.8 × 10–2 and was negatively correlated with discharge (r = –0.85, d.f. = 13, P < 0.001). 3. The percentage of hyporheic zone water which came from surface water varied as a function of discharge and hyporheic depth, ranging between 33% and 95% at 25 cm depth, and between 78% and 100% at 10 cm depth. 4. The nutrient retention efficiency in the hyporheic zone at 10 cm depth measured as uptake length (Swh) was less than 3.3 cm for ammonium and 37 cm for phosphate. Higher nutrient retentions were measured in the sediments at 10 cm depth than at 25 cm, indicating that near-surface sediments were involved more actively in phosphate retention than the deeper hyporheic sediments. The lack of ammonium at any depth of the hyporheic zone showed that ammonium was very rapidly taken up in the surfacial sediments. 相似文献
49.
Lladó A Timpson P Vilà de Muga S Moretó J Pol A Grewal T Daly RJ Enrich C Tebar F 《Molecular biology of the cell》2008,19(1):17-29
The intracellular trafficking of the epidermal growth factor receptor (EGFR) is regulated by a cross-talk between calmodulin (CaM) and protein kinase Cδ (PKCδ). On inhibition of CaM, PKCδ promotes the formation of enlarged early endosomes and blocks EGFR recycling and degradation. Here, we show that PKCδ impairs EGFR trafficking due to the formation of an F-actin coat surrounding early endosomes. The PKCδ-induced polymerization of actin is orchestrated by the Arp2/3 complex and requires the interaction of cortactin with PKCδ. Accordingly, inhibition of actin polymerization by using cytochalasin D or by overexpression of active cofilin, restored the normal morphology of the organelle and the recycling of EGFR. Similar results were obtained after down-regulation of cortactin and the sequestration of the Arp2/3 complex. Furthermore we demonstrate an interaction of cortactin with CaM and PKCδ, the latter being dependent on CaM inhibition. In summary, this study provides the first evidence that CaM and PKCδ organize actin dynamics in the early endosomal compartment, thereby regulating the intracellular trafficking of EGFR. 相似文献
50.
Extracellular vesicles do not contribute to higher circulating levels of soluble LRP1 in idiopathic dilated cardiomyopathy 下载免费PDF全文
Santiago Roura Carolina Gálvez‐Montón David de Gonzalo‐Calvo Ana Gámez Valero Paloma Gastelurrutia Elena Revuelta‐López Cristina Prat‐Vidal Carolina Soler‐Botija Aida Llucià‐Valldeperas Isaac Perea‐Gil Oriol Iborra‐Egea Francesc E. Borràs Josep Lupón Vicenta Llorente‐Cortés Antoni Bayes‐Genis 《Journal of cellular and molecular medicine》2017,21(11):3000-3009
Idiopathic dilated cardiomyopathy (IDCM) is a frequent cause of heart transplantation. Potentially valuable blood markers are being sought, and low‐density lipoprotein receptor‐related protein 1 (LRP1) has been linked to the underlying molecular basis of the disease. This study compared circulating levels of soluble LRP1 (sLRP1) in IDCM patients and healthy controls and elucidated whether sLRP1 is exported out of the myocardium through extracellular vesicles (EVs) to gain a better understanding of the pathogenesis of the disease. LRP1 α chain expression was analysed in samples collected from the left ventricles of explanted hearts using immunohistochemistry. sLRP1 concentrations were determined in platelet‐free plasma by enzyme‐linked immunosorbent assay. Plasma‐derived EVs were extracted by size‐exclusion chromatography (SEC) and characterized by nanoparticle tracking analysis and cryo‐transmission electron microscopy. The distributions of vesicular (CD9, CD81) and myocardial (caveolin‐3) proteins and LRP1 α chain were assessed in SEC fractions by flow cytometry. LRP1 α chain was preferably localized to blood vessels in IDCM compared to control myocardium. Circulating sLRP1 was increased in IDCM patients. CD9‐ and CD81‐positive fractions enriched with membrane vesicles with the expected size and morphology were isolated from both groups. The LRP1 α chain was not present in these SEC fractions, which were also positive for caveolin‐3. The increase in circulating sLRP1 in IDCM patients may be clinically valuable. Although EVs do not contribute to higher sLRP1 levels in IDCM, a comprehensive analysis of EV content would provide further insights into the search for novel blood markers. 相似文献