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1.
Carles Grau Romuald Ginhoux Alejandro Riera Thanh Lam Nguyen Hubert Chauvat Michel Berg Julià L. Amengual Alvaro Pascual-Leone Giulio Ruffini 《PloS one》2014,9(8)
Human sensory and motor systems provide the natural means for the exchange of information between individuals, and, hence, the basis for human civilization. The recent development of brain-computer interfaces (BCI) has provided an important element for the creation of brain-to-brain communication systems, and precise brain stimulation techniques are now available for the realization of non-invasive computer-brain interfaces (CBI). These technologies, BCI and CBI, can be combined to realize the vision of non-invasive, computer-mediated brain-to-brain (B2B) communication between subjects (hyperinteraction). Here we demonstrate the conscious transmission of information between human brains through the intact scalp and without intervention of motor or peripheral sensory systems. Pseudo-random binary streams encoding words were transmitted between the minds of emitter and receiver subjects separated by great distances, representing the realization of the first human brain-to-brain interface. In a series of experiments, we established internet-mediated B2B communication by combining a BCI based on voluntary motor imagery-controlled electroencephalographic (EEG) changes with a CBI inducing the conscious perception of phosphenes (light flashes) through neuronavigated, robotized transcranial magnetic stimulation (TMS), with special care taken to block sensory (tactile, visual or auditory) cues. Our results provide a critical proof-of-principle demonstration for the development of conscious B2B communication technologies. More fully developed, related implementations will open new research venues in cognitive, social and clinical neuroscience and the scientific study of consciousness. We envision that hyperinteraction technologies will eventually have a profound impact on the social structure of our civilization and raise important ethical issues. 相似文献
2.
Elicitation of Necrosis in Vigna unguiculata Walp. by Homogeneous Aspergillus niger Endo-Polygalacturonase and by alpha-d-Galacturonate Oligomers
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Endo-polygalacturonase (PG) was purified from a commercial preparation of Aspergillus niger pectinase by means of carboxymethylcellulose chromatography, preparative isoelectric focusing, and gel permeation through Sephadex G-50. The enzyme was electrophoretically homogeneous and consisted of a single polypeptide chain with a molecular weight of 33,500. The enzyme exhibited a specific activity significantly higher than those of purified polygalacturonases from phytopathogenic fungi. Galacturonate oligomers with a degree of polymerization higher than four appeared quickly as products of the enzymic hydrolysis of Napolygalacturonate. The oligomers were later degraded to di- and monogalacturonate. The homogeneous enzyme and growing mycelium of Aspergillus niger separately elicited a necrotic response in cowpea (Vigna unguiculata Walp.) pods. Heat-inactivated PG and PG inactivated with specific antibodies did not elicit necrosis, suggesting that the catalytic activity of the enzyme is necessary for its function as an elicitor. The PG-released oligosaccharides from Vigna cell wall and the galacturonides with a degree of polymerization greater than four separately elicited necrosis, whereas di- and monogalacturonate did not. 相似文献
3.
Caminal G Lafuente J López-Santín J Poch M Solà C 《Biotechnology and bioengineering》1987,29(3):366-369
A recursive estimation scheme, the Extended Kalman Filter (EKF) technique, was applied to study enzymatic deactivation in the enzymatic hydrolysis of pretreated cellulose using a model previously developed by the authors. When no deactivation model was assumed, the results showed no variation with time for all the model parameters except for the maximum rate of cellobiose-to-glucose conversion (r'(m)).The r'(m) variation occurred in two zones with a grace period. A new model of enzymatic hydrolysis of pretreated cellulose deactivation was proposed and validated showing better behavior than the old deactivation model. This approach allows one to study enzyme deactivation without additional experiments and within operational conditions. 相似文献
4.
Mathematical modelization of a packed-bed reactor performance with immobilized yeast for ethanol fermentation 总被引:1,自引:0,他引:1
The performance of a continuous vertical packed-bed reactor with yeast immobilized in carrageenan gel beads is reported. The study focuses on the mathematical modelling of the steady-state fermentor behavior by means of a tanks-in-series model which includes the intrinsic kinetic model and the external mass transfer and internal diffusion-reaction conditions in the beads. 相似文献
5.
Mario Marini Gianna Roscetti Lucilla Bongiorno Alessandra Urbani L. Giorgio Roda 《Neurochemical research》1990,15(1):61-67
Seven groups of enkephalin-degrading enzymes and three groups of inhibitors active on these enzymes were separated from human plasma. The activity of the enzymes in hydrolyzing enkephalins and of the inhibitors in protecting enkephalins from proteolysis was measured. Results obtained with the endogenous inhibitors were compared to those relative to synthetic inhibitors. Data obtained indicate that all enkephalin-degrading enzymes found in plasma are significantly inhibited by the endogenous substances present in this tissue. The inhibition of the different classes of plasma enzymes by two of the three groups of endogenous substances is quite uniform, while one group of inhibitors appears specific to dipeptidylpeptidases. Results obtained are discussed in terms of the functional role of the inhibitory substances and of the possible pharmacological implication of their presence in human plasma. 相似文献
6.
7.
Summary A 2.5-fold increase in the release of intracellular anthraquinones was obtained by adding 1 ml L-1 silicone A to suspension cultures of Morinda citrifolia. Cell growth and secondary metabolite production were not affected even at high silicone A concentrations. Performance of the silicone treatment in a two-liquid-phase system (5 ml n-hexadecane/50 ml medium) resulted in a 150% increase of the overall secondary metabolite productivity. 相似文献
8.
Serafina Salvati Lucilla Attorri Lorenzo Malvezzi Campeggi Antonella Olivieri Mariella Sorcini Stefano Fortuna Annita Pintor 《Neurochemical research》1994,19(9):1181-1186
The effect of hypothyroidism on the lipid composition of synaptosomes, density and affinity of muscarinic receptor sites, and acetylcholinesterase activity in the cerebral cortex of young and aged rats was investigated. The animals were made hypothyroid by adding 0.05% propyl-2-thiouracil to their drinking water for four weeks. This pathological state induced an increase in the relative percentage of sphingomyelin in young rats. In aged rats hypothyroidism induced a decrease of sphingomyelin and glycerophosphocholine and an increase of cholesterol. The effect of hypothyroid state on cerebral cortex resulted in an increase of acethylcholinesterase activity both in young and aged rats and was also reflected in an increase of density of M1-AChRs but only in the former. 相似文献
9.
Nirvana Sadaghianloo Julie Contenti Maeva Dufies Julien Parola Matthieu Rouleau Shinrong Lee Jean-François Peyron Lucilla Fabbri Réda Hassen-Khodja Jacques Pouysségur Frédéric Bost Elixène Jean-Baptiste Alan Dardik Nathalie M. Mazure 《Journal of cellular and molecular medicine》2020,24(5):2931-2941
Arteriovenous fistulas (AVFs) are the preferred vascular access for haemodialysis of patients suffering from end-stage renal disease, a worldwide public health problem. However, they are prone to a high rate of failure due to neointimal hyperplasia and stenosis. This study aimed to determine if osteopontin (OPN) was induced in hypoxia and if OPN could be responsible for driving AVF failure. Identification of new factors that participate in remodelling of AVFs is a challenge. Three cell lines representing the cells of the three layers of the walls of arteries and veins, fibroblasts, smooth muscle cells and endothelial cells, were tested in mono- and co-culture in vitro for OPN expression and secretion in normoxia compared to hypoxia after silencing the hypoxia-inducible factors (HIF-1α, HIF-2α and HIF-1/2α) with siRNA or after treatment with an inhibitor of NF-kB. None of the cells in mono-culture showed OPN induction in hypoxia, whereas cells in co-culture secreted OPN in hypoxia. The changes in oxygenation that occur during AVF maturation up-regulate secretion of OPN through cell-cell interactions between the different cell layers that form AVF, and in turn, these promote endothelial cell proliferation and could participate in neointimal hyperplasia. 相似文献
10.
Peña Claudia Civit Bárbara Gallego-Schmid Alejandro Druckman Angela Pires Armando Caldeira- Weidema Bo Mieras Eric Wang Feng Fava Jim Canals Llorenç Milà i Cordella Mauro Arbuckle Peter Valdivia Sonia Fallaha Sophie Motta Wladmir 《The International Journal of Life Cycle Assessment》2021,26(2):215-220
The International Journal of Life Cycle Assessment - The current global interest in circular economy (CE) opens an opportunity to make society’s consumption and production patterns more... 相似文献