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Summary Leydig cell nuclear area and 5-3-hydroxysteroid dehydrogenase activity were increased in the testis ofBufo melanostictus 2 days after a single short-term cold exposure. Both parameters returned to normal values 4 days later.  相似文献   
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Molasses was used as an alternative binder to the bentonite binder. The change in moisture absorption by pellets prepared with different iron ores and different molasses contents were investigated. Iron ore properties exerted the major effect on pellet behavior and final pellet quality. The absorbed moisture content of pellets prepared without binder, bentonite-added pellets, and molasses-added pellets were in the range of 7.72%–9.95%, 9.62%–10.84%, and 6.14%-6.69%, respectively. The wet pellet compressive strength of molasses-added pellets(43–230 N/pellet) was superior to that of bentonite-added pellets(9.47–11.92 N/pellet). The compressive strength of dried molasses-modified pellets increased to 222–394 N/pellet, which is currently the highest value achieved for dried pellets.  相似文献   
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Malignant transformation, driven by gain-of-function mutations in oncogenes and loss-of-function mutations in tumour suppressor genes, results in cell deregulation that is frequently associated with enhanced cellular stress (for example, oxidative, replicative, metabolic and proteotoxic stress, and DNA damage). Adaptation to this stress phenotype is required for cancer cells to survive, and consequently cancer cells may become dependent upon non-oncogenes that do not ordinarily perform such a vital function in normal cells. Thus, targeting these non-oncogene dependencies in the context of a transformed genotype may result in a synthetic lethal interaction and the selective death of cancer cells. Here we used a cell-based small-molecule screening and quantitative proteomics approach that resulted in the unbiased identification of a small molecule that selectively kills cancer cells but not normal cells. Piperlongumine increases the level of reactive oxygen species (ROS) and apoptotic cell death in both cancer cells and normal cells engineered to have a cancer genotype, irrespective of p53 status, but it has little effect on either rapidly or slowly dividing primary normal cells. Significant antitumour effects are observed in piperlongumine-treated mouse xenograft tumour models, with no apparent toxicity in normal mice. Moreover, piperlongumine potently inhibits the growth of spontaneously formed malignant breast tumours and their associated metastases in mice. Our results demonstrate the ability of a small molecule to induce apoptosis selectively in cells that have a cancer genotype, by targeting a non-oncogene co-dependency acquired through the expression of the cancer genotype in response to transformation-induced oxidative stress.  相似文献   
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The Linz-Donawitz (LD) steelmaking process produces LD slag at a rate of about 125 kg/t. After metallic scrap recovery, the non-metallic LD slag is rejected because its physical/chemical properties are unsuitable for recycling. X-ray diffraction (XRD) studies have indicated that non-metallic LD slag contains a substantial quantity of mineral phases such as di- and tricalcium silicates. The availability of these mineral phases indicates that LD slag can be recycled by iron (Fe)-ore sintering. However, the presence of 1.2wt% phosphorus (P) in the slag renders the material unsuitable for sintering operations. Electron probe microscopic analysis (EPMA) studies indicated concentration of phosphorus in dicalcium silicate phase as calcium phosphate. The Fe-bearing phases (i.e., wustite and dicalcium ferrite) showed comparatively lower concentrations of P compared with other phases in the slag. Attempts were made to lower the P content of LD slag by adopting various beneficiation techniques. Dry high-intensity magnetic separation and jigging were performed on as-received samples with particle sizes of 6 and 3 mm. Spiral separation was conducted using samples ground to sizes of less than 1 and 0.5 mm. Among these studies, grinding to 0.5 mm followed by spiral concentration demonstrated the best results, yielding a concentrate with about 0.75wt% P and 45wt% Fe.  相似文献   
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A near eutectic Al?12.6Si alloy was developed with 0.0wt%, 2.0wt%, 4.0wt%, and 6.0wt% Al?5Ti?1B master alloy. The microstructural morphology, hardness, tensile strength, elongation, and fracture behaviour of the alloys were studied. The unmodified Al?12.6Si alloy has an irregular needle and plate-like eutectic silicon (ESi) and coarse polygonal primary silicon (PSi) particles in the matrix-like α-Al phase. The PSi, ESi, and α-Al morphology and volume fraction were changed due to the addition of the Al?5Ti?1B master alloy. The hardness, UTS, and elongation improved due to the microstructural modification. Nano-sized in-situ Al3Ti particles and ex-situ TiB2 particles caused the microstructural modification. The fracture images of the developed alloys exhibit a ductile and brittle mode of fracture at the same time. The Al?5Ti?1B modified alloys have a more ductile mode of fracture and more dimples compared to the unmodified alloy.  相似文献   
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Chronic treatment of mice with the synthetic cannabinoid nabilone (50 mg/kg, 3 times per week) reduced the number of pachytene spermatocytes. Nabilone did not affect other cell types in the testis or the sex organ weights. Nabilone tended to increase the number of abnormal spermatozoa, but this did not reach statistical significance. It is concluded that nabilone causes less testicular toxicity than the natural cannabinoids.  相似文献   
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Locomotion in mammals relies on a central pattern-generating circuitry of spinal interneurons established during development that coordinates limb movement. These networks produce left-right alternation of limbs as well as coordinated activation of flexor and extensor muscles. Here we show that a premature stop codon in the DMRT3 gene has a major effect on the pattern of locomotion in horses. The mutation is permissive for the ability to perform alternate gaits and has a favourable effect on harness racing performance. Examination of wild-type and Dmrt3-null mice demonstrates that Dmrt3 is expressed in the dI6 subdivision of spinal cord neurons, takes part in neuronal specification within this subdivision, and is critical for the normal development of a coordinated locomotor network controlling limb movements. Our discovery positions Dmrt3 in a pivotal role for configuring the spinal circuits controlling stride in vertebrates. The DMRT3 mutation has had a major effect on the diversification of the domestic horse, as the altered gait characteristics of a number of breeds apparently require this mutation.  相似文献   
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