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排序方式: 共有611条查询结果,搜索用时 15 毫秒
1.
Lately we have seen quite a few Microsoft vulnerabilities — the most noteworthy being the Object Data vulnerability, which Microsoft attempted to fix with the patches in security bulletin MS03-032. The Object Data vulnerability is extremely easy to exploit — like MS01-020 which is still being exploited by many viruses (e.g. ‘Swen’ currently roaming the Internet). The vulnerability has already beenexploited by a spammer, who wanted to promote his porn site and by a hacker, who compromised an online hotel.  相似文献   
2.
Three different methods for the simultaneous analysis of surface phenotype and DNA quantification were compared. One method, involving the fixation of cells in 70% ethanol, was convincingly superior, both with regard to the CV of the G0G1 peak and the intensity of the DNA labelling. Furthermore, the correlation between the surface antigen densities before and after fixation were high. Experiments evaluating the intraday and the interday variation of the DNA ratio (the mean channel of the G0G1 peak of the sample divided by the mean channel of the G0G1 peak of chicken erythrocytes), documented the former to be small, with S.D. values varying from 0.0 to 0.016, while the latter were considerably higher with S.D. values varying from 0.077 to 0.123. Since the intraday variation of the DNA ratio was consistently low and the interday variation strongly correlated to the position of the red fluorescence test beads, it was possible to minimize the interday variation of the DNA ratio, by calculating the DNA index as the ratio between the DNA ratio of the sample and that of an external control (buffy coat leukocytes). Analyzing normal bone marrow and calculating the DNA index (DI) on the basis of these ratios, the confidence limits of the DI were decreased by more than half the values obtained when DI calculation was based solely on an internal standard, thereby making subsequent ploidy determinations of patient samples more precise. We conclude that this setup of internal and external standards allows accurate determinations of DNA aneuploidy even in an assay where whole cells labelled for surface antigen and DNA content are analyzed.  相似文献   
3.
A model of human neonatal ovary is presented, derived from morphometric, evaluations carried out on left ovaries removed from five full-term neonates with a 46, XX karyotype, free from malformations of the genital apparatus. According to this model, the gonad can be represented by a triaxial ellipsoid with a central medullary core surrounded by a cortical stratum of constant thickness. The germinal population, consisting of follicles and primitive cortical tissue, occupies the cortex, intermingled with the interstitium or stroma. In the cortex it is then possible to describe an outer layer formed by primitive cortical tissue, and an inner portion occupied by follicles. The primary and secondary follicles fill the portion near the medulla and the primordial ones are contained in the middle and outer zones. Since the variability observed among ovaries is slight, we can propose a mean model of neonatal ovary in which the spatial relationships among the different components, the total number of follicles and their position in the cortex can be calculated.  相似文献   
4.
2400-year solar cycle ascertained by us in the long-term series of various natural characteristics (e.g. the radiocarbon content in samples of well-known ages, oscillations of the sea and ocean levels etc.) includes three parts roughly equal in duration: a phase of high activity, a phase of depression and a phase of moderate activity. In climate oscillations, which are connected with this cycle, the next phenomena are established: a little climatic optimum, a little Ice Age, and a temperate climate epoch.  相似文献   
5.
Jet injection can be used to introduce genes into the cells of differentiated tissues of living animals and organ cultures. When a solution of plasmid DNA is jet injected into a selected tissue or organ, cells lying in or near the path of the jet injection are transfected with the DNA and the introduced gene(s) are expressed. Since there is minimal morbidity from each jet injection, multiple injections can be performed at the same or nearby sites. Both mRNA and protein expression from transfected genes can be quantitated using standard methods. In addition, the technique is an efficient means of DNA immunization. Methodology for using jet injection to transfer plasmid DNA into the cells of skin, fat, mammary gland, and muscle are described.  相似文献   
6.
The results of clinical and laboratory studies on the use of augmentin in severe purulent complications after neurosurgical operations are presented. The laboratory studies carried out with the use of an automatic system Cobas Bact (Roch) showed that the numbers of the augmentin resistant strains of Staphylococcus and Enterobacteriaceae among the pathogens were 47 and an average of 64.5%, respectively. Gram-negative bacteria resistant to augmentin were 1.5 to 2 times less frequent than those resistant to amoxycillin. Still, they were much more frequent than those resistant to cefotaxime and ceftriaxone. Clinical efficacy of augmentin was studied in treatment of 39 patients with various affections of the brain such as tumors, trauma, vascular malformations and inflammatory processes. The postoperative complications were represented by meningitis, pneumonia, sepsis and their associations. The use of augmentin in the severe intra- and extracranial complications was favourable in 82.1% of the cases.  相似文献   
7.
Creative processes are complex and consist of sub‐processes, e.g. value creation, scaffolding, imagination and materialization. Creativity takes place in a physical context, i.e. in a confined space. Such space restricts and enables the free flow of sensory experiences and proximity of other people. The confinements may make certain sensory experiences available, e.g. vision of source material, sight and sound (including noise). This framing allows certain cognitive processes and restricts others. This may induce emotions that, in turn, facilitate or reduce the enhancement of creativity. Physical space affects the well‐being of people, the channels of information, the availability of knowledge tools and sets the stage for coherence and continuity, which may contribute to competitive advantages.  相似文献   
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9.
A melt pelletization process was investigated in an 8 litre laboratory scale high shear mixer using a formulation with paracetamol, glyceryl monostearate 40-50, and microcrystalline wax. The effects of jacket temperature, product temperature during massing, product load, massing time and impeller speed were investigated by means of factorially designed experiments. The maximum yield of pellets in the range of 500-1400μm was found to approx. 90%. For process conditions preventing deposition of moist mass, the process was found to be reproducible. Impeller speed and massing time were found to be important process variables. Remarkably low in vitro drug release rates were observed in USP-dissolution tests.  相似文献   
10.
Hemostasis of 100 patients with severe diphtheria infection was studied throughout the disease. The patients were found to have marked procoagulant, anticoagulant and fibrinolytic disorders. Antithrombogenic activity of the vascular wall was also abnormal. The above impairments correlated with the symptoms severity and are interpreted as DIC syndrome which ran subclinically or as hemorrhagic syndrome. The majority of the patients underwent a hyperhypocoagulant phase of DIC syndrome.  相似文献   
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