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71.
Due to their ecological and economic importance, honey bees have attracted much scientific attention, which has intensified due to the recent population decline of these insects in the several parts of the world. Among the factors related to these patterns, infection by pathogens are the most relevant, mainly because of the easy dissemination of these microorganisms. Although no zoonotic diseases are associated with these insects, the presence of infectious agents in bee products should still be considered because they play a role as disease dispersers, increasing the risk to animal health. Because of the possibility of dispersion of pathogens via bee products, this work aimed to identify the presence of spores of the pathogens Paenibacillus larvae, Ascosphaera apis and Nosema spp. in samples of honey, pollen and royal jelly that are registered with Brazil's Federal Inspection Service (S.I.F.) and commercially available in the state of São Paulo. Of the 41 samples of bee products analyzed, only one showed no contamination by any of these pathogens. N. ceranae and P. larvae had the highest prevalence considering all the samples analyzed (present in 87.80% and 85.37% of the total, respectively), with N. apis present in 26.83% and A. apis present in 73.17% of the samples. These results provide support for the formulation of government regulations for sanitary control of exotic diseases by preventing dispersion of pathogens, including through illegal importation, since local and international trade and the transfer of colonies between regions play important roles in the dispersion of these microorganisms.  相似文献   
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73.
Microscopic analysis of 82 royal jelly samples obtained from several locations in Greece was carried out in order to study the pollen spectrum of Greek royal jelly. The analysis recorded over 60 taxa. The abundance of each pollen type varied among the areas and the samples. The most frequent pollen types found in the samples were Brassicaceae, Olea europaea, Eucalyptus, Trifolium, Rubus, Carduus-type, Hypericum, Daucus-type and Cistus. The majority of the pollen types found in the royal jelly samples were also found at the pollen flora around the apiaries.  相似文献   
74.
Referee: Dr. C. Neal Stewart, Jr., Department of Plant Science and Landscape Systems, The University of Tennessee, 2431 Center Drive, Knoxville, TN 37996-4561 There is major international concern over the widescale contamination of soil and associated groundwater by persistant explosives residues. The development of methods to remediate these contaminants has been a significant research interest for several decades. In the last 10 years, phytoremediation has emerged as a focus for explosives remediation because of its low cost, low energy requirements, and promising research observing explosives removal from contaminated groundwater and soil. More recent work has focused on the modes of transformation and metabolism of energetic compounds by plants. These biochemical studies and the experimental conditions enabling the degradation and uptake of explosives by different plant species are discussed.  相似文献   
75.
The effects of royal jelly (RJ) appear to be conserved in Drosophila; flies exposed of RJ exhibit increased body size, similar to queen bees. However, in flies and bees, there is evidence that increased body size can lead to impairments to locomotor activity, while RJ may have anti-fatigue properties. Canton-S and Oregon-R Drosophila larvae were raised on media containing 0% or 20% pure RJ. Climbing assays were conducted to assess vertical locomotion. Circadian locomotion was observed using Drosophila Activity Monitors. CS, but not Or-R, raised on RJ were larger compared to controls. Flies exposed to RJ exhibited entrainment and free-running rhythms. The increased size due to RJ exposure in this study had no bearing on circadian locomotor activity or climbing. These results indicate that there is variation among physiological responses to RJ among different strains, but RJ was equally ineffective in affecting locomotor behavior no matter the physiological response.  相似文献   
76.
The Family of Major Royal Jelly Proteins and Its Evolution   总被引:8,自引:0,他引:8  
A cDNA encoding a new member of the gene family of major royal jelly proteins (MRJPs) from the honeybee, Apis mellifera, was isolated and sequenced. Royal jelly (RJ) is a secretion of the cephalic glands of nurse bees. The origin and biological function of the protein component (12.5%, w/w) of RJ is unknown. We show that the MRJP gene family encodes a group of closely related proteins that share a common evolutionary origin with the yellow protein of Drosophila melanogaster. Yellow protein functions in cuticle pigmentation in D. melanogaster. The MRJPs appear to have evolved a novel nutritional function in the honeybee. Received: 26 September 1998 / Accepted: 28 February 1999  相似文献   
77.
Hypothesis: a model for generalised autoimmunity   总被引:6,自引:0,他引:6  
A detailed mechanism for the development of generalised autoimmunity is suggested, and the significance of the association between autoimmunity and leukemia is discussed.  相似文献   
78.
79.
The term natural cytotoxicity (NC) describes a phenomenon in rats whereby significant numbers of intravenously injected 51Cr-labeled lymph node cells are rapidly destroyed by unsensitized allogeneic hosts. Cell death is reflected in a decreased accumulation of labeled cells in the host lymph nodes, with a corresponding increase in the label excreted by the kidney. Natural cytotoxicity has been studied in 95 allogeneic donor-host combinations among inbred rats and in a segregating population of F1 backcross animals. On the basis of lymphocyte distribution patterns, the individual donor-host combinations have been categorized as exhibiting high NC (13 strain combinations), intermediate NC (63 strain combinations), or low NC (19 strain combinations). Analysis of the segregating F1 backcross population showed NC to be controlled by at least two independently segregating genes, one of which was linked to the MHC, and the other of which was possibly, but by no means certainly, X linked. No linkage was demonstrated with respect to coat color loci (C, A, H) or to kappa chain allotype (RI-1). Natural cytotoxicity appears to belong to a group of several phenomena characterized by the rapid destruction of allogeneic cells by apparently unsensitized hosts.  相似文献   
80.
The effects of cadmium on production of cyclic AMP by partially purified chick renal plasma membrane preparations and binding of 125I-parathyrin to the membranes have been investigated. At certain concentrations Cd2+ ions (and Mn2+ ions) markedly stimulated the production of cyclic AMP by the tissue. It was found that concentrations of Cd2+ roughly in the same range were also capable of stimulating binding of 125I-parathyrin to the membrane preparations.  相似文献   
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