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91.
92.
Subchronic animal feeding studies to examine the effect on the immune system of genetically modified corn CBH351, which contains the Cry9C protein derived from Bacillus thuringiensis subspecies tolworthi, were conducted in female BN rats and B10A mice. The studies were designed to compare the effect of a line of genetically modified corn CBH351 (GM corn) with that of isoline corn (non-GM corn). Heat-treated corn meal was incorporated into the diets of the rats and mice at a concentration of 50%. The study duration was 13 weeks. Growth, food intake, and organ weights of the thymus, spleen, and liver were compared between animals fed the non-GM and GM lines. The histological findings in thymus, spleen, mesenteric lymph nodes, Peyer's patches, small intestines, liver, kidney, and bone marrow, and the presence of Cry9C-specific IgE, IgG, IgG1 and IgA antibodies in serum were also compared. The results showed no significant differences in growth, feeding value, or the histological findings in immunity-related organs between the animals fed the GM and non-GM lines. Production of Cry9 C-specific IgE and IgA was not detected in the serum of either group. Production of Cry9C-specific IgG and IgG1 was slightly increased in the 50% GM groups of BN rats. No Cry9C-specific IgG or IgG1 was detected in the serum of BN rats fed the diet containing 5% GM-corn In conclusion, no immunotoxic activity was detected in the GM-corn-fed rats and mice in this subchronic dietary study.  相似文献   
93.
Yogurt is a well-known nutritious and probiotic food and is traditionally fermented from milk using the symbiotic starter culture of Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus. However, yogurt consumption may cause health problems in lactose-intolerant individuals, and the demand for lactose-free yogurt has been increasing. The standard method to prepare lactose-free yogurt is to hydrolyze milk by lactase; however, this process has been reported to influence the fermentation properties of starter strains. This study aimed to investigate the fermentation properties of an industrial starter culture of L. bulgaricus 2038 and S. thermophilus 1131 in lactose-hydrolyzed milk and to examine the metabolic changes induced by glucose utilization. We found that the cell number of L. bulgaricus 2038, exopolysaccharide concentration, and viscosity in the coculture of L. bulgaricus 2038 and S. thermophilus 1131 was significantly increased in lactose-hydrolyzed milk compared with that in unhydrolyzed milk. Although the cell number of S. thermophilus 1131 showed no difference, production of formic acid and reduction of dissolved oxygen were enhanced in lactose-hydrolyzed milk. Further, in lactose-hydrolyzed milk, S. thermophilus 1131 was found to have increased the expression of NADH oxidase, which is responsible for oxygen reduction. These results indicated that glucose utilization promoted S. thermophilus 1131 to rapidly reduce the dissolved oxygen amount and produce a high concentration of formic acid, presumably resulting in the increased cell number of L. bulgaricus 2038 in the coculture. Our study provides basic information on the metabolic changes in starter strains in lactose-hydrolyzed milk, and demonstrates that lactose-free yogurt with increased cell number of L. bulgaricus can be prepared without delay in fermentation and decrease in the cell number of S. thermophilus.  相似文献   
94.
A novel real-time PCR-based analytical method was developed for the event-specific quantification of a genetically modified (GM) soybean event; A2704-12. During the plant transformation, DNA fragments derived from pUC19 plasmid were integrated in A2704-12, and the region was found to be A2704-12 specific. The pUC19-derived DNA sequences were used as primers for the specific detection of A2704-12. We first tried to construct a standard plasmid for A2704-12 quantification using pUC19. However, non-specific signals appeared with both qualitative and quantitative PCR analyses using the specific primers with pUC19 as a template, and we then constructed a plasmid using pBR322. The conversion factor (C(f)), which is required to calculate the amount of the genetically modified organism (GMO), was experimentally determined with two real-time PCR instruments, the Applied Biosystems 7900HT and the Applied Biosystems 7500. The determined C(f) values were both 0.98. The quantitative method was evaluated by means of blind tests in multi-laboratory trials using the two real-time PCR instruments. The limit of quantitation for the method was estimated to be 0.1%. The trueness and precision were evaluated as the bias and reproducibility of relative standard deviation (RSD(R)), and the determined bias and RSD(R) values for the method were each less than 20%. These results suggest that the developed method would be suitable for practical analyses for the detection and quantification of A2704-12.  相似文献   
95.
In this study, a combined use of biopolymer chitosan and oxidoreductase polyphenol oxidase (PPO) was applied to the removal of bisphenol A (BPA) as an endocrine disrupting chemical from aqueous solutions. The optimum conditions for the enzymatic quinone oxidation of BPA were determined to be pH 7.0 and 40°C. Quinone derivatives generated were chemisorbed on chitosan beads, and BPA was completely removed at 4–7 h. The removal time was shortened with an increase in the amount of dispersed chitosan beads or the PPO concentration. In addition, the initial velocity of quinone oxidation increased with an increase in the amount of chitosan beads. The use of chitosan in the form of porous beads was more effective than the use of chitosan in the form of solutions or powder. It was found that an important factor for this procedure was a high‐specific surface area of chitosan beads and heterogeneous reaction of quinone derivatives enzymatically generated with chitosan. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   
96.
This study was performed to explore possible environmental risk factors, including indoor chemicals, mold, and dust mite allergens, which could cause sick building syndrome (SBS)-type symptoms in new houses. The study was conducted in 2004 and 2005 and the final study population consisted of 86 men and 84 women residing in Okayama, Japan. The indoor concentrations of indoor aldehydes, volatile organic compounds, airborne fungi, and dust mite allergens in their living rooms were measured and the longitudinal changes in two consecutive years were calculated. A standardized questionnaire was used concomitantly to gather information on frequency of SBS-type symptoms and lifestyle habits. About 10% of the subjects suffered from SBS in the both years. Crude analyses indicated tendencies for aldehyde levels to increase frequently and markedly in the newly diseased and ongoing SBS groups. Among the chemical factors and molds examined, increases in benzene and in Aspergillus contributed to the occurrence of SBS in the logistic regression model. Indoor chemicals were the main contributors to subjective symptoms associated with SBS. A preventive strategy designed to lower exposure to indoor chemicals may be able to counter the occurrence of SBS.  相似文献   
97.
Poly(L ‐lactide) (PLA) was melt‐blended with four rubber components—ethylene–propylene copolymer, ethylene–acrylic rubber, acrylonitrile–butadiene rubber (NBR), and isoprene rubber (IR)—in an effort to toughen PLA. All the blend samples exhibited distinct phase separation. Amorphous PLA constituted a topologically continuous matrix in which the rubber particles were dispersed. According to Izod impact testing, toughening was achieved only when PLA was blended with NBR, which showed the smallest particle size in its blend samples. In agreement with the morphological analysis, the value of the interfacial tension between the PLA phase and the NBR phase was the lowest, and this suggested that rubber with a high polarity was more suitable for toughening PLA. Under the tensile stress conditions for NBR and IR blend samples, these rubbers displayed no crosslinking and showed a high ability to induce plastic deformation before the break as well as high elongation properties; this suggested that the intrinsic mobility of the rubber was important for the dissipation of the breaking energy. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   
98.
Trichosporon asahii is a pathogenic basidiomycetous yeast. Individual strains of T. asahii have different colony morphologies. However, it is not clear whether cell surface phenotypes differ among the colony morphologies. Here we characterized the cell surface hydrophobicity and analysed the carbohydrate contents of the cell surface polysaccharides in T. asahii clinical isolates with various colony morphologies. Among the three distinctive colony morphologies obtained from one clinical isolate, the white‐type morphology exhibited higher hydrophobicity. The hydrophobicity of heat‐killed T. asahii cells was greatly reduced after periodate oxidation of the cell surface carbohydrates. Furthermore, the cell wall and extracellular polysaccharide components differed among the morphologies. Our results suggest that T. asahii cell surface hydrophobicity is affected by cell surface carbohydrate composition. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
99.
100.
Acquired idiopathic generalized anhidrosis (AIGA) is a rare disorder in which systemic anhidrosis/hypohidrosis occurs without causative dermatological, metabolic or neurological disorder. Most cases of AIGA have been reported in Asia, especially in Japan, but there have been only a few reports in Europe and the United States. Severe AIGA may result in heatstroke and can reduce quality of life due to restriction of exercise and outdoor works. AIGA is often accompanied by cholinergic urticaria (CholU), and it is thought that AIGA and CholU with anhidrosis/hypohidrosis belong to the same spectrum of the disease. However, the pathophysiology of AIGA has not yet been clarified. Decreased expression of cholinergic receptor M3 on the epithelial cells of eccrine sweat glands is often accompanied by T cell infiltration around eccrine apparatus, suggesting an immunological mechanism of disordered perspiration. AIGA is occasionally associated with various complications indicative of autoimmune disorders. The association of autoimmune complications further suggests that AIGA is an autoimmune disorder. Studies on complications may lead to a better understanding of the pathophysiology of AIGA.  相似文献   
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