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1.
A recombinant scFv antibody against human spleen ferritin was expressed as a barstar-fused protein in Escherichia coli and in Nicotiana tabacum plants and suspension cell cultures. As demonstrated by immunoblotting with antibarstar antibodies, direction of the recombinant protein to the endomembrane system of plant cells ensured its stability and solubility. Production of the recombinant protein did not differ between parental transgenic plants and their first-generation progeny. Fusion with barstar allowed not only immunochemical detection of the recombinant scFv antibody, but also their purification from the plant material by affinity chromatography with barnase-His6 immobilized on a metal-affinity carrier.  相似文献   
2.
The content of malonyl dialdehyde, one of the final products of lipid peroxidation, was determined at different stages after zymosan stimulation of mononuclear phagocyte system in the rat liver. The gradual increase (with the maximum on day 7) of colloidal carbon clearance from the blood and the number of nonparenchymal cells, especially their nonphagocytic fraction, was noted in the rat liver after zymosan injection. A considerable reduction of hepatic malonyl dialdehyde was observed after the initial (on day 1) rising of its level. The distinct antioxidant effect developed by day 7 and coincided with maximal activity of hepatic macrophages.  相似文献   
3.
Globally, the most widely used wetland classification is that adopted by the contracting parties of the Ramsar Convention, which is the Convention on Wetlands of International Importance especially as Waterfowl Habitat. A review of the Inland Wetland component of this system shows that mixed criteria are used to separate the wetlands, and that not all natural inland wetlands have been addressed. A classification system using landform and hydro-period, which results in 13 primary geomorphically non-emergent types for natural wetlands, is proposed to describe the full variety of wetlands at a primary level around the globe, and is suggested to be incorporated as the first-tier of the Ramsar classification.The proposed classification has been designed so wetlands can be described, classified and compared systematically. This paper attempts to reconcile the Ramsar Classification system with the proposed approach. The intention in this paper is not to displace the Ramsar Classification, but rather to indicate its inherent underlying geomorphic structure, and hence re-order its hierarchical framework. This adjustment to the existing classification system would highlight underlying similarities between wetlands so that global comparisons can be more readily made. It also has considerable advantages for a staged, systematic discrimination and classification of the vast array of differing wetlands globally.The use of geomorphic and hydrologic elements as the primary and secondary divisions with the more commonly used Ramsar Classification terms as a tertiary division, provides a logical structure to compare and contrast wetlands globally.  相似文献   
4.
    
In species with indeterminate growth, differential growth rates can lead to animals adopting alternative reproductive tactics such as sneak–guard phenotypes, which is partially predicted by variation in growth during the juvenile life‐history stage. To investigate sources of growth variation, we examined the independent and joint effects of paternal reproductive tactic (G) and rearing environment (E) on juvenile growth in Chinook salmon (Oncorhynchus tshawytscha), hypothesizing G and E effects are partially mediated through differences in behaviour such as aggressive interactions and resulting foraging behaviours. We created maternal half‐sibling families with one‐half of the female's eggs fertilized by the milt of a sneaker “jack” and the other half by a guarder “hooknose”. At the exogenous feeding stage, each split‐clutch family was then divided again and reared in a rationed diet or growth‐promotion diet environment for approximately 6 months, during which growth parameters were measured. Before saltwater transfer at 9 months of age, social interactions were observed in groups of six fish of various competitor origins. We found ration restricts growth rate and juvenile mass, and evidence of genetic effects on growth depensation, where jack‐sired individuals grew less uniformly over time. These growth‐related differences influenced an individual's level of aggression, with individuals raised on a restricted diet and those whose families experienced greatest growth being most aggressive. These individuals were more likely to feed than not and feed most often. Jack‐sired individuals were additionally aggressive in the absence of food, and when raised on a rationed diet outcompeted others to feed most. These results show how individuals may achieve higher growth rates via intrinsic (G) or induced (E) aggressive behavioural phenotypes, and eventually attain the threshold body size necessary during the saltwater phase to precociously sexually mature and adopt alternative reproductive phenotypes.  相似文献   
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Seeds of 5 rose species, Rosa multiflora Thunb. ‘Cathayensis,’ R. × reversa Waldst. & Kit., R. setigera Michx. ‘Beltsville,’ R. setigera Michx. ‘Serena,’ and R. wichuraiana Crepin, varied in after-ripening requirement from 30 days at 4.4 C for R. multiflora to 90 days for R. setigera ‘Serena.’ The compensating temperature varied from near 12.8 C for R. × reversa to a value near 29.4 C for R. setigera ‘Beltsville.’ In this report compensating temperature is used to describe that temperature at which mature, moist seed does not germinate, after-ripening does not take place, and dormancy does not change. Seed germination was reduced by interruption of the after-ripening period with intervals at temperatures above the compensating temperature. The interruptions were more effective in reducing germination when more frequent and when the temperature during the interval was higher. Species differed in their sensitivity to high-temperature reduction of germination. Those having the longest after-ripening requirement were most sensitive. Germination of seeds which had the minimum after-ripening treatment was repressed more by high temperature than germination of those seeds which had an excess of after-ripening. The decrease in germination resulted from imposition of a secondary dormancy of the embryo, and probably also from reversal of the after-ripening effect upon the primary dormancy imposed by the seed coat.  相似文献   
7.
    
The presence of foraging bears in Arctic breeding bird colonies has been increasingly reported in the literature, and these may constitute disturbance events which cause incubating birds to leave their nest. Avian predators may associate with bears during such events, likely to capitalize on unattended nests in the presence of bears. Here, we estimated changes in daily nest attendance of lesser snow geese Anser caerulescens caerulescens in the presence of foraging bears, and estimated the association between foraging bears and avian predators. We predicted decreased nest attendance by geese on days with bears, and close associations between avian predators and bears. We monitored snow goose nests with cameras from 2013 to 2018 to assess nest attendance behaviours on days when bears were in the colony compared to control days without bears. When bears were present in colonies, we estimated the probability of avian predator occurrence compared to control periods. When controlling for day of incubation and camera placement types, we found no significant effects of bears on daily nest attendance behaviours of snow geese (n = 85). We found a significantly higher probability of observing avian predators when bears were present (0.72) compared to control periods without bears (0.11). We show that snow geese do not alter daily nest attendance in the presence of foraging bears, and suggest this is due to the presence of avian predators.  相似文献   
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Mucins have been shown to be aberrantly overexpressed in various diseases including cystic fibrosis, asthma, and cancer. Recent studies have uncovered the roles of these mucins in the pathogenesis of cancer. The presence of MUC-1 has also been detected on the cell surface of multiple myeloma (MM) cells in peripheral blood and showed direct correlation with tumor mass. In this study, we evaluated the levels of soluble MUC-1 (sMUC-1) in 50 new MM patients and correlated this with the levels of sMUC-1 after treatment. High levels of sMUC-1 were found in 20/50 (40%) MM patients, and in 2/50 (4%) healthy individuals (p = 0.001). According to the ISS, we found significant differences of mean sMUC-1 levels between the first stage of the disease (0.63 ± ± 0.26) and the third (0.93 ± 0.24; p = 0.03), but not with the second stage (0.80 ± 0.22; p = 0.08). Our study confirmed the correlation between elevated sMUC-1 and high elevated lactate dehydrogenase (p = 0.03) and the level of IgG in groups of patients with MM IgG at every stage of disease (p = 0.001). We showed for the first time that levels of sMUC-1 after treatment, in a group of patients with initially elevated levels of MUC-1, were statistically lower than in a group of patients with initially lower levels of sMUC-1 (21% vs. 42,6%; p = 0.05). At 37 months median of follow-up, we found a statistically significant difference between patients with normal versus elevated sMUC-1 in terms of progression-free survival (median 12 months vs. 8.1 months; p = 0.03).  相似文献   
10.
Two mutant plastogenes in all possible chimeral combinations were followed in Pelargonium X hortorum Bailey (geranium) shoots. The part of stem, leaf, or other structure derived from each apical layer was clearly apparent on a cell to cell basis. Shoots typically were composed of derivatives of three apical layers but we found derivatives of as many as four apical layers in some leaves and of five layers in some stems. In chimeras with one of the mutants, Dpl W1, the amount of tissue derived from the various apical layers was the same, whether the layer was mutant or wild type. We suggest that there are independent apical layers and cell lineages derived from them in nonchimeral shoots, and that their contribution in normal ontogeny is like that of the layers in Dpl W1 chimeras. In chimeras carrying the second mutant, Dpl W2, there was much less tissue derived from mutant than from wild-type apical layers. The phenotypic expression of the plastogenes was unchanged by their transmission through male or female gametes. Comparisons of the ontogeny of geranium plants carrying the W1 or W2 mutant suggested that, while there was competition between the apical layers and between their derivatives, the genome imposed a definite harmonious interaction or accommodation which led to a final normal morphology of all plant parts and organs through quite different ontogenetic pathways.  相似文献   
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