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51.
The overuse of in-feed antibiotics has been associated with serious issues, including the developing of antibiotic-resistant pathogens and causing drug residues in poultry products. To date, many countries have restricted the use of growth-promoting antibiotics in food animals, resulting in the increased need for effective alternatives to in-feed antibiotic. Synbiotics, which are composed of probiotics and prebiotics, have been shown to act synergistically when applied simultaneously. Thus, this study investigated the effects of a synbiotic, composed of microencapsulated Lactobacillus plantarum (MLP) and fructooligosaccharide (FOS), on growth, immune and antioxidant parameters, and digestibility of calcium and phosphorus in broilers. A total of 168 newly hatched male broilers were randomly allotted to three dietary groups (n = 7): (1) a corn-soybean meal basal diet (CON); (2) basal diet + synbiotic (SYN); and (3) basal diet + aureomycin (ANT). Compared with the CON, chickens had greater average daily gain and digestibility of calcium and phosphorus in the SYN group (P < 0.05). In the SYN and ANT group, serum IgA, IgG, and IL-10 levels were higher, while the serum TNF-α, IL-2, and IL-6 levels were reduced (P < 0.05) compared to CON. Compared with CON, the level of serum malondialdehyde was lower (P < 0.05) and SOD level was higher (P < 0.05) in either SYN or ANT group. No significant differences in populations of Escherichia coli were seen in chickens among the three groups, whereas, the populations of Lactobacillus were higher (P < 0.05) in chickens in the SYN group compared with those in CON and ANT groups. Taken together, the addition of SYN, consisting of MLP and FOS, had benefits on growth, immune and antioxidant parameters, and digestibility of calcium and phosphorus, indicating its potential to serve as a substitute for antibiotics in broiler feeding.  相似文献   
52.
Hemodynamic simulation in a novel design for femoral bypass grafts   总被引:1,自引:0,他引:1  
Qiao A  Matsuzawa T 《Biorheology》2007,44(2):103-124
The effectiveness of femoral bypass grafts is correlated with the geometric configuration and hemodynamics of the bypass and the arteries. As an attempt to develop a new design for femoral bypass grafts, we present a novel geometric configuration for a symmetrically implanted 2-way bypass graft. In order to investigate how the symmetric 2-way bypass grafts affect the flow patterns through the anastomosis, physiologic blood flows in 1-way and 2-way models for a fully stenosed femoral bypass were simulated with the finite element method, and the hemodynamic factors in these models were studied. The temporal and spatial distributions of flow patterns and wall shear stresses in the vicinity of distal anastomosis during the cardiac cycle were analyzed. The results computed showed that the 2-way model has more preferable hemodynamics than the 1-way model in the distribution of flow patterns and wall shear stresses, and it may improve the flow conditions and decrease the probability of restenosis. However, the limitations of the 2-way bypass model may counteract the positive effects. More detailed hemodynamic studies are necessary to fully assess the viability of the 2-way bypass graft.  相似文献   
53.
In Drosophila, pheromones play a crucial role in regulating courtship behaviors. In males, female aphrodisiac pheromones promote male‐female courtship, and male antiaphrodisiac pheromones inhibit male‐male courtship. Previous studies have reported that receptor proteins belonging to the pickpocket (ppk) family, ionotropic receptor family and gustatory receptor family are required for pheromone detection and normal courtship. However, none of them has been shown to be sufficient for sensing pheromones after ectopic expression in originally unresponsive cells. “M” cells are activated by male antiaphrodisiac pheromones but not female aphrodisiac pheromones, and the activated cells inhibit male‐male courtship. In our study, male flies with ectopic expression of ppk25, ppk29 and ppk23 in “M” cells showed decreased male‐female courtship. Using an in vivo calcium imaging approach, we found that the “M” cells expressing these three ppks were significantly activated by the female aphrodisiac pheromone 7,11‐heptacosadiene (7,11‐HD). Our results indicate that a sodium channel consisting, at minimum, of ppk25, ppk29 and ppk23, can sense 7,11‐HD, most likely as a receptor. Our findings may help us gain insights into the molecular mechanisms of pheromonal functions.  相似文献   
54.
Neuroscience as a distinct discipline or research programme has been a rather recent event in most Chinese universities and in the Chinese Academy of Sciences. However, the last few years have witnessed increased funding and an improved research environment for neuroscience, both of which facilitated an influx of Chinese neuroscientists trained abroad. In this review, we have highlighted some recent research advances made by neuroscientists in China. Based on our own expertise, this review is focused mainly on findings that have contributed to our understanding of the mechanisms underlying brain development, neural plasticity and cognitive processes, and neural degeneration.  相似文献   
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The adenylate cyclase/cAMP signaling pathway and adult mushroom bodies (MBs) have been shown to play an important role in sleep regulation in Drosophila. The amnesiac (amn) gene, encodes a neuropeptide that is homologous with vertebrate pituitary adenylate cyclase-activating peptide (PACAP), is expressed in dorsal paired medial (DPM) neurons and is required for the middle-term memory (MTM) in flies. However, the role of amn on regulation of sleep is as yet unknown. Here we provide evidence that amn plays a major role on sleep maintenance and onset in Drosophila. Flies with the amnesiac allele, loss-of-function amnX8 mutation, showed a fragmented sleep pattern and short sleep latency. Moreover, homeostatic regulation was disrupted in amnX8 mutants after sleep deprivation. Sleep maintenance was also influenced by disruption of neurotransmission in DPM neurons with increased sleep bout number and decreased sleep bout length. Furthermore, age-related sleep fragmentation and initiation were inhibited in amnX8 mutant flies. These data suggest that amn is required in initiation and maintenance of sleep.  相似文献   
58.
The Coronary Artery Bypass Graft (CABG) yields excellent results and remains the modern standard of care for treatment of occlusive disease in the cardiovascular system. However, the development of anastomotic Intimal Hyperplasia (IH) and restenosis can compromise the medium-and-long term effects of the CABG. This problem can be correlated with the geometric configuration and hemodynamics of the bypass graft. A novel geometric configuration was proposed for the CABG with two symmetrically implanted grafts for the purpose of improving the hemodynamics. Physiological blood flows in two models of bypass grafts were simulated using numerical methods. One model was for the conventional bypass configuration with a single graft (1-way model); the other model was for the proposed bypass configuration with two grafts (2-way model). The temporal and spatial distributions of hemodynamics, such as flow patterns and Wall Shear Stress (WSS) in the vicinity of the distal anastomoses, were analyzed and compared. Calculation results showed that the 2-way model possessed favorable hemodynamics with uniform longitudinal flow patterns and WSS distributions, which could decrease the probability of restenosis and improve the effect of the surgical treatment. Concerning the limitations of the 2-way bypass grafts, it is necessary to perform animal experiments to verify the viability of this novel idea for the CABG.  相似文献   
59.
It has been suggested that in the olfactory bulb, odor information is processed through parallel channels and learning depends on the cognitive environment. The synapse’s spike effective time is defined as the effective time for a spike from pre-synapse to post-synapse, which varies with the type of synapse. A learning model of the olfactory bulb was constructed for synapses with varying spike effective times. The simulation results showed that such a model can realize the multi-channel processing of information in the bulb. Furthermore, the effect of the cognitive environment on the learning process was also studied. Different feedback frequencies were used to express different attention states. Considering the information’s multi-channel processing requirement for learning, a learning rule considering both spike timing and average spike frequency is proposed. Simulation results showed that habituation and anti-habituation of an odor in the olfactory bulb might be the result of learning guided by a common local learning rule but at different attention states.  相似文献   
60.
Hemodynamic factors may affect the potential occurrence of in-stent restenosis (ISR) after intervention procedure of vertebral artery ostial stenosis (VAOS). The purpose of the present study is to investigate the influence of stent protrusion length in implantation strategy on the local hemodynamics of the VAOS. CTA images of a 58-year-old female patient with posterior circulation transient ischemic attack were used to perform a 3D reconstruction of the vertebral artery. Five models of the vertebral artery before and after the stent implantation were established. Model 1 was without stent implantation, Model 2–5 was with stent protruding into the subclavian artery for 0, 1, 2, 3 mm, respectively. Computational fluid dynamics simulations based on finite element analysis were employed to mimic the blood flow in arteries and to assess hemodynamic conditions, particularly the blood flow velocity and wall shear stress (WSS). The WSS and the blood flow velocity at the vertebral artery ostium were reduced by 85.33 and 35.36% respectively after stents implantation. The phenomenon of helical flow disappeared. Hemodynamics comparison showed that stent struts that protruded 1 mm into the subclavian artery induced the least decrease in blood speed and WSS. The results suggest that stent implantation can improve the hemodynamics of VAOS, while stent struts that had protruded 1 mm into the subclavian artery would result in less thrombogenesis and neointimal hyperplasia and most likely decrease the risk of ISR.  相似文献   
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