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71.
The importance of cytokines in disc degeneration is well recognized. Little is known about IL-22 expression in the human intervertebral disc. We investigated IL-22 immuno-localization in disc tissue, and molecular expression and production of IL-22 by annulus cells cultured in three-dimensional (3D) culture. We examined human disc tissue using immunohistochemistry and we cultured isolated annulus cells in 3D to analyze IL-22 expression and production, and its receptor, IL-22R, in conditioned media. Ingenuity pathway analysis (IPA) also was used to identify significant gene expression networks within the molecular data. IL-22 and IL-22R were immunolocalized in many cells in the human outer and inner annulus; fewer cells exhibited localization in the nucleus. Three-dimensional culture of annulus cells demonstrated production of IL-22 in conditioned media; exposure to IL-1ß or TNF-α significantly reduced IL-22 levels. Significant decreases also were identified in conditioned media assayed for IL-22R in TNF-α treated cells. IPA analysis showed that IL-22 ranked among the top canonical pathways. We found constitutive expression and production of IL-22 and IL-22R in the disc, which expands our understanding of the effect of pro-inflammatory cytokines on IL-22 expression and production. Three-dimensional cultured annulus cells exposed to IL-1ß or TNF produced significantly lower levels of IL-22 into their conditioned media compared to levels produced by control cells. Our findings have clinical relevance because of the elevated pro-inflammatory milieu within the degenerating human disc.  相似文献   
72.
Investigating the tolerance of plant reproductive systems to environmental changes has become a research priority under current climate change scenarios. Successful plant conservation requires knowledge of plant reproductive biology, particularly the meiotic characteristics of planted species. Meiosis, as part of microsporogenesis, is a critical plant developmental stage controlling future pollen quality. Meiosis in a Siberian fir (Abies sibirica) plantation, established in the Forest Arboretum of the Sukachev Institute, Russia, was studied from 2002 to 2004. The microsporogenesis pattern found for the Siberian fir appeared to be largely similar to that exhibited by other conifer species. Meiosis in the Siberian fir has the following characteristics: asynchrony, rapid progression of telophases I and II, and parallel and linear spindle arrangements at different meiosis II stages. General and specific meiosis irregularities were recorded at each stage. Some specific features of meiosis and the specific development of some irregularities were revealed. Pollen development analysis showed that irregular pollen grains made up less than 1% of all grains. The specific features of meiosis identified in fir trees growing in the Arboretum indicated low resistance of male reproductive structures to climatic changes and might account for high fir pollen sterility in this new environment.  相似文献   
73.
Biology Bulletin - In a laboratory pot experiment, two mutant cultivars of sunflower (Helianthus annuus cv. r2p2 and Helianthus annuus cv. r5n1) were grown on soils with anthropogenic polyelemental...  相似文献   
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The effects of calmodulin and chlorpromazine on purified phospholipase A2 preparations from snake venoms: cobra (Naja naja oxiana), echis (Ehis multisquamatus) and Agkistrodon halys halys, as well as on phospholipases A2 from rat liver mitochondria and human platelets were studied. It was shown that within the concentration range of 1-5 microM calmodulin stimulates the phospholipase activity. Chlorpromazine inhibits the activity of these enzymes, the degree of inhibition being different for various phospholipases. Calmodulin was shown to interact with the phospholipases in the absence of exogenous Ca2+. The results obtained indicate that all phospholipases tested are calmodulin-dependent enzymes.  相似文献   
76.

Background  

Efficient and accurate prediction of protein function from sequence is one of the standing problems in Biology. The generalised use of sequence alignments for inferring function promotes the propagation of errors, and there are limits to its applicability. Several machine learning methods have been applied to predict protein function, but they lose much of the information encoded by protein sequences because they need to transform them to obtain data of fixed length.  相似文献   
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The microbial communities and their degradative potential in rhizospheres of alfalfa (Medicago sativa) and reed (Phragmites australis) and in unplanted soil in response to bitumen contamination of soil were studied in pot experiments. According to the results of fluorescence microscopy, over a period of 27 months, bitumen contamination of soil reduced the total number of microorganisms more significantly (by 75%) in unplanted than in rhizosphere soil (by 42% and 7% for reed and alfalfa, respectively) and had various effects on some important physiological groups of microorganisms such as actinomycetes as well as nitrogen-fixing, nitrifying, denitrifying, ammonifying, phosphate-solubilizing, sulphur-oxidizing, cellulolytic and hydrocarbon-degrading microorganisms. The changes in the physiological structure of the microbial community under bitumen contamination were found to hinge on not merely the presence of plants but also their type. It was noted that the rhizosphere microflora of alfalfa was less inhibited by hydrocarbon pollution and had a higher degradative potential than the rhizosphere microflora of reed.  相似文献   
79.
A Biosurfactant-Producing Pseudomonas aeruginosa Strain   总被引:3,自引:0,他引:3  
A Pseudomonas aeruginosa strain producing an extracellular surfactant (biosurfactant) was isolated. The growth of this strain, referred to as 50.3, on a mineral glycerol-containing medium produces an emulsifying activity (60%) and decreases the surface tension of the culture liquid by a factor of 2.8 (to 25 mN/m). The optimum conditions for its growth and production of biosurfactants are intense aeration, pH 7.0–8.0, and the presence of Mg2+. The optimum biosurfactant properties were achieved when glucose was used as the only source of carbon and energy and NH4Cl was used as a source of nitrogen. The biosurfactant was isolated from the culture liquid by extraction and precipitation.  相似文献   
80.
The tiger shrimp (Penaeus monodon) is an important marine crustacean in terms of biological diversity and aquaculture resource. The shrimp is widespread across the Indo‐Pacific region and shows apparent genetic differentiation among geographical populations. It is common practice to transport female brooders between different countries to seed the shrimp farms, posing potential problems of unwanted population admixture. We developed 23 polymorphic microsatellites for P. monodon (average HE = 0.936) and these microsatellites were applicable for studying population differentiation, identifying valid stocks and tagging nonindigenous farmed shrimps.  相似文献   
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