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421.
Therapeutic horse riding or hippotherapy is used as an intervention for treating individuals with mental and physical disabilities. Equine-assisted interventions are based on the hypothesis that the movement of the horse's pelvis during horseback riding resembles human ambulation, and thus provides motor and sensory inputs similar to those received during human walking. However, this hypothesis has not been investigated quantitatively and qualitatively. This study aimed to verify the hypothesis by conducting a three-dimensional analysis of the horse's movements while walking and human ambulation. Using four sets of equipments, we analysed the acceleration patterns of walking in 50 healthy humans and 11 horses. In addition, we analysed the exercise intensity by comparing the heart rate, breathing rate, and blood pressure of 127 healthy individuals before and after walking and horse riding. The acceleration data series of the stride phase of horse walking were compared with those of human walking, and the frequencies (in Hz) were analysed by Fast Fourier transform.The acceleration curves of human walking overlapped with those of horse walking, with the frequency band of human walking corresponding with that of horse walking. Exercise intensity, as measured by the heart rate and breathing rate, was not significantly different between horse riding and human walking. The levels of diastolic blood pressure were slightly higher during horse riding than during walking, but were lower during both conditions compared with those in normal conditions (P < 0.01). The present study shows that, although not completely matched, the accelerations of the horse and human walking are comparable quantitatively and qualitatively. Horse riding at a walking gait could generate motor and sensory inputs similar to those produced by human walking, and thus could provide optimum benefits to persons with ambulatory difficulties.  相似文献   
422.
Newborn neurons maintain a very simple, bipolar shape, while they migrate from their birthplace toward their destinations in the brain, where they differentiate into mature neurons with complex dendritic morphologies. Here, we report a mechanism by which the termination of neuronal migration is maintained in the postnatal olfactory bulb (OB). During neuronal deceleration in the OB, newborn neurons transiently extend a protrusion from the proximal part of their leading process in the resting phase, which we refer to as a filopodium‐like lateral protrusion (FLP). The FLP formation is induced by PlexinD1 downregulation and local Rac1 activation, which coincide with microtubule reorganization and the pausing of somal translocation. The somal translocation of resting neurons is suppressed by microtubule polymerization within the FLP. The timing of neuronal migration termination, controlled by Sema3E‐PlexinD1‐Rac1 signaling, influences the final positioning, dendritic patterns, and functions of the neurons in the OB. These results suggest that PlexinD1 signaling controls FLP formation and the termination of neuronal migration through a precise control of microtubule dynamics.  相似文献   
423.
A novel α-galactosidase gene ( aga2 ) was cloned from Bifidobacterium breve 203. It contained an ORF of 2226-bp nucleotides encoding 741 amino acids with a calculated molecular mass of 81.5 kDa. The recombinant enzyme Aga2 was heterogeneously expressed, purified and characterized. Regarding substrate specificity for hydrolysis, Aga2 was highly active towards p -nitrophenyl-α- d -galactopyranoside ( p NPG). The K m value for p NPG was estimated to be 0.27 mM and for melibiose it was estimated to be 4.3 mM. Aga2 was capable of catalyzing transglycosylation as well as hydrolysis. The enzyme synthesized a trisaccharide (Gal-α-1, 4-Gal-α-1, 6-Glc) using melibiose as a substrate. It was a new oligosaccharide produced by glycosidase and contained Gal-α-1,4 linkage, a novel galactosidic link formed by microbial α-galactosidase. In the presence of p NPG as a donor, Aga2 was able to catalyze glycosyl transfer to various acceptors including monosaccharides, disaccharides and sugar alcohols.  相似文献   
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To assess the ability of immunoglobulin production in vivo, we enumerated the immunoglobulin secreting cells in the peripheral blood of patients with an IgA deficiency and of those with hyper-IgAemia. All seven patients with primary IgA deficiency and two of the three patients with secondary IgA deficiency had low numbers of IgA secreting cells. In all five patients with hyper-IgA the number of IgA secreting cells was increased. Our results suggest that measurement of immunoglobulin secreting cells in PBMCs is useful in the assessment of ability of immunoglobulin production in vivo.Abbreviations PBMCs peripheral blood mononuclear cells - MEM minimum essential medium - PFC plaque forming cells - VH immunoglobulin heavy chain variable region - CH immunoglobulin heavy chain constant region  相似文献   
427.
Many studies have highlighted the difficulty inherent to the clinical application of fundamental neuroscience knowledge based on machine learning techniques. It is difficult to generalize machine learning brain markers to the data acquired from independent imaging sites, mainly due to large site differences in functional magnetic resonance imaging. We address the difficulty of finding a generalizable marker of major depressive disorder (MDD) that would distinguish patients from healthy controls based on resting-state functional connectivity patterns. For the discovery dataset with 713 participants from 4 imaging sites, we removed site differences using our recently developed harmonization method and developed a machine learning MDD classifier. The classifier achieved an approximately 70% generalization accuracy for an independent validation dataset with 521 participants from 5 different imaging sites. The successful generalization to a perfectly independent dataset acquired from multiple imaging sites is novel and ensures scientific reproducibility and clinical applicability.

Biomarkers for psychiatric disorders based on neuroimaging data have yet to be put to practical use. This study overcomes the problems of inter-site differences in fMRI data by using a novel harmonization method, thereby successfully constructing a generalizable brain network marker of major depressive disorder across multiple imaging sites.  相似文献   
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Enantioselectivity-promoting factor enhances enantioselectivity of protonation in lipase AP-catalyzed asymmetric hydrolysis of enol esters. The factor was partially purified by chromatography using Phenyl-TOYOPEARL 650M and Sephacryl S-200HR. The hydrolysis of 2-benzyl-l-cyclohexenyl acetate by PLE in the presence of the purified factor produced (R)-2-benzylcyclo-hexanone in 92% ee, while the reaction without the factor gave the racemate.  相似文献   
430.
The predominant ganglioside in sea urchin eggs, M5 (NeuGc  相似文献   
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