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81.
During business collaboration, partners may benefit through sharing data. People may use data mining tools to discover useful relationships from shared data. However, some relationships are sensitive to the data owners and they hope to conceal them before sharing. In this paper, we address this problem in forms of association rule hiding. A hiding method based on evolutionary multi-objective optimization (EMO) is proposed, which performs the hiding task by selectively inserting items into the database to decrease the confidence of sensitive rules below specified thresholds. The side effects generated during the hiding process are taken as optimization goals to be minimized. HypE, a recently proposed EMO algorithm, is utilized to identify promising transactions for modification to minimize side effects. Results on real datasets demonstrate that the proposed method can effectively perform sanitization with fewer damages to the non-sensitive knowledge in most cases. 相似文献
82.
Processing of lipid-modified prolipoprotein requires energy and sec gene products in vivo. 下载免费PDF全文
The kinetics of processing of glyceride-modified prolipoprotein that accumulated in globomycin-treated Escherichia coli has been found to be affected by sec mutations, i.e., secA, secE, secY, secD, and secF, and by metabolic poisons which affect proton motive force (PMF). The effect of sec mutations on processing of glyceride-modified prolipoprotein in vivo was not due to a secondary effect on PMF. Neither a secF mutation nor metabolic poisons affected the processing of previously accumulated proOmpA protein in vivo, suggesting that the requirements for functional sec gene products and PMF are specific to the processing of lipoprotein precursors by signal peptidase II. 相似文献
83.
Chemical and microbiological solubilization of silicates 总被引:1,自引:0,他引:1
S. Friedrich N. P. Platonova G. I. Karavaiko E. Stichel F. Glombitza 《Engineering in Life Science》1991,11(3):187-196
The solubilization of silicates was investigated using kaolin and quartz sand as model substances. The mineral solubilization was studied in the concentration of solubilized Si and Al. The chemical leaching of the silicates was carried out using inorganic and organic acids as well as sodium hydroxide. The process was more effective in the alkine than in the acid pH range. In the acid medium, oxalic acid showed maximum acidity and a tendency to form complex structures, especially with aluminium, and was most effective in leaching. The microbiological influence on solubilization reactions was tested using a number of microorganisms among them acid, alkali and slime-forming species. The highest leaching activity was observed in the case of Thiobacillus thiooxidans, whereas the heterotrophic microorganisms (among them Bacillus mucilaginosus) did not exercise a sollubilizing effect on the silicates. X-ray phase analysis of leached kaolin samples did not show any differences from the non-leached mineral. 相似文献
84.
Evaluation of a trapping ELISA for the differentiation of foot-and-mouth disease virus strains using monoclonal antibodies. 总被引:1,自引:0,他引:1
A trapping enzyme-linked immunosorbent assay (ELISA) has been evaluated for the differentiation of foot-and-mouth disease virus (FMDV) strains using a panel of seven anti-serotype O monoclonal antibodies (MAbs). The variation of results within and between tests performed on the same day and on different days was examined using three strains of FMDV. Criteria for establishing antigenic differences between the strains as defined by the individual MAbs are proposed based on the variability measured, which can be used as standards by workers performing this test with other MAbs and FMDV strains. 相似文献
85.
86.
V V Abramov A G Mustafin V N Iarygin V A Kozlov 《Biulleten' eksperimental'no? biologii i meditsiny》1991,112(12):621-623
Immunization of Wistar rats with thymus dependent antigens (sheep red blood cells-SRBC) is accompanied by a reliable increase in the synthesis of RNA and proteins in thalamic cerebral cortex and spinal marrow (48 hrs after antigen injection) and also in an increase in the intensity of rapid axoplasmic transport (RAT) along motor fibers of sciatic nerve (5,48,72 hrs following the beginning of immunization). There was a consecutive augmentation in AFC number in mesenteric and partly in inguinal lymph nodes (96 hrs after SRBC injection). Thus, time dependence between immunogenesis and axoplasmic transport in experimental animals (Wistar rats) was determined for the first time. It identifies another, previously unstudied, channel in interactions of immune and nervous systems. 相似文献
87.
J. A. M. van Eekelen N. Y. Rots W. Sutanto M. S. Oitzl E. R. de Kloet 《The Journal of steroid biochemistry and molecular biology》1991,40(4-6):679-683
The present study examined the stress responsiveness of the hypothalamic-pituitary-adrenal axis in relation to the properties of corticosteroid receptors in the brain and pituitary in old (30 months) and young (3 months) male Brown Norway rats. The data demonstrate that circulating ACTH rather than the corticosteroid plasma level was elevated under basal conditions and following stress. Furthermore, a reduction of mineralocorticoid receptor (MR) number in the hippocampus and of glucocorticoid receptor (GR) number in the hypothalamus and the pituitary correspond to increased neuroendocrine responsiveness and negative feedback following stress. The changes in receptor binding do not parallel the changes in the amount of MR and GR mRNA measured with in situ hybridization. This suggests that the processing rather than the receptor gene expression is affected in senescence. 相似文献
88.
J Müller A Torsson M Damkjaer Nielsen K E Petersen J Christoffersen N E Skakkebaek 《Hormone research》1991,36(5-6):203-208
We have investigated gonadal development and growth in 4 individuals (3 with 46,XY and 1 with 46,XX karyotype) with P450scc deficiency. One patient died at 2 months of age from adrenal insufficiency, while the remaining 3 individuals were healthy and developed normally (age at follow-up: 18, 10 and 8 years). In the surviving individuals, the diagnosis was established during the first 2-4 months of life by extensive endocrine studies of blood and urine. In the remaining patient, the diagnosis was made on the basis of karyotype (46,XY), anatomy of internal and external genitalia and adrenal pathology. Gonadectomy was performed in the 2 surviving 46,XY individuals at the age of 7 years, and histological examination showed normal testicular morphology but very few germ cells. Postmortem examination of the testes of the 2-month-old subject showed normal testicular histology, and quantitative analysis revealed a normal number of germ cells. Ultrasound of the 46,XX individual showed normal internal female genitalia including ovaries with follicles. The 3 surviving patients grew along the 75th (46,XY), the 90th (46,XY) and the 50th percentile (46,XX), respectively. The oldest girl experienced normal breast and pubic hair development after oral estrogen replacement and topical testosterone administration. The glucocorticoid and mineralocorticoid replacement was adjusted in accordance with repeated measurements of serum sodium and serum potassium, plasma renin concentration and blood pressure. No attempts were made to normalize serum ACTH. We conclude that prenatal testicular maturation and development of female internal genitalia may take place in the absence of normal steroid hormone production. Normal growth and development may be obtained in P450scc-deficient individuals with adequate hormone replacement. 相似文献
89.
Summary In the solid substrate fermentation of cooked yellow corn grits with Rhizopus oligosporus in a rocking drum fermenter, temperature was controlled by blowing air through the substrate, forcing water evaporation. The rate of evaporation was controlled by the relative humidity of the air, according to the rate of heat generation during fermentation. Moisture content was maintained constant by spraying cold water on the substrate regulated by the water balance equation of the system. Both controls were operated by computer programs. The rocking motion in the reactor allowed even distribution of air and water in the substrate without disturbing the growing mycelia. 相似文献
90.