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1.
A dynamic investigation was done of the immunologic status in 75 patients with purulent surgical lesions of soft tissues. Applied in the complex of therapeutic measures was intracorporeal irradiation of blood with ultraviolet light under control of partial pressure of oxygen and carbon dioxide. The above irradiation was found out to make for a more rapid and marked stabilization of bodily immunologic status. 相似文献
2.
The study and creation of the infrastructure required to enable system-level science--the integration of diverse sources of knowledge about the constituent parts of a complex system with the goal of obtaining an understanding of the system's properties as a whole--is becoming increasingly important, spawning new knowledge in variety of fields at a rapid pace. 相似文献
3.
RA Coutinho 《Canadian Metallurgical Quarterly》1997,141(21):1034-1036
Until recently, an HIV test was of limited importance for persons who had been at risk for HIV as effective drugs were not available. With the advent of a new generation of antiretroviral drugs with beneficial effect after early treatment, knowledge of the HIV serostatus has become of more importance to asymptomatic persons. There is no need for a mass screening campaign however, as there is no cure as yet. 相似文献
4.
The Internet technology known as the World Wide Web is rapidly emerging as the most powerful medium of mass communication this century and it can be harnessed to dispense global, cost-effective, high-quality, multimedia patient education material. This paper reviews how the Internet has progressed from delivering simple static, text-based material to sophisticated interactive Web sites based on CGI Technology. Interactive Web sites can be used to deliver health assessment questionnaires and Web-based decision-support systems can give patients advice on the emergency management of acute medical problems. The advantages and drawbacks of this new technology, including information regulation and quality are discussed. The role of the Hospital Intranet as a patient education resource is described. The paper concludes by illustrating how patients can appreciate the 3-D structure of bones and organs using virtual reality in a VRML Web environment. 相似文献
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Ubiquitin-mediated proteolysis controls the abundance of many cell cycle regulatory proteins. Recent work in Saccharomyces cerevisiae suggests that a complex consisting of Cdc53, Skp1, and a third component known as an F-box protein (termed SCF) in combination with Cdc34 specifically targets regulatory proteins for degradation, and that substrate specificity is likely to be mediated by the F-box subunit. A screen for genetic interactions with a cdc34 mutation yielded MET30, which encodes an F-box protein. MET30 is an essential gene required for cell cycle progression and met30 mutations interact genetically with mutations in SCF components. Furthermore, physical interactions between Met30, Cdc53, Cdc34, and Skp1 in vivo provide evidence for an SCFMet30 complex. We demonstrate the involvement of Met30 in the degradation of the Cdk-inhibitory kinase Swe1. Swe1 is stabilized in met30 mutants and GST-Met30 pull-down experiments reveal that Met30 specifically binds Swe1 in vivo. Furthermore, extracts prepared from cdc34 or met30 mutants are defective in polyubiquitination of Swe1. Taken together, these data suggest that SCF-mediated proteolysis may contribute to the regulation of entry into mitosis. Our data, in combination with previously published results, also provide evidence for distinct SCF complexes in vivo and support the idea that their F-box subunits mediate SCF substrate specificity. 相似文献
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The multicatalytic proteinase complex (MPC, proteasome) is assembled from 14 nonidentical protein subunits. It expresses five distinct proteolytic activities, including a chymotrypsin-like activity, cleaving after hydrophobic residues, and a branched chain amino acid-preferring component (BrAAP), cleaving preferentially after branched chain residues. Exposure of cells to interferons leads to replacement of the X, Y, and Z subunits by the LMP2, LMP7, and MECL1 subunits. This "immunoproteasome" is critical to processing of certain antigens. The enzymatic basis for enhanced antigen processing has not been determined. To gain insight into this question, we examined sites and relative rates of cleavage of bonds in denatured, reduced, carboxyamidomethylated lysozyme, a 129-amino acid protein, by MPC from bovine spleen, in which the X, Y, and Z subunits are replaced by LMP2, LMP7, and MECL1. We compared cleavages to those catalyzed by MPC from bovine pituitary, which contains only the X, Y, and Z subunits. We found marked increases in the rates and number of cleavages after branched chain residues in reduced, carboxyamidomethylated lysozyme by the spleen MPC. This was largely due to accelerated cleavages of bonds after a Phi-X-Br motif, where Phi is a hydrophobic residue, X is a small neutral or polar residue, and Br is a branched chain residue. Inhibitors with these structural properties were selective and potent inhibitors of the BrAAP activity of the spleen MPC. The above findings indicate that alterations in activity and substrate specificity of the BrAAP activity are important factors underlying the altered cleavages after hydrophobic residues associated with incorporation of interferon-inducible subunits. The potential relevance of the findings to antigen processing functions of MPC is discussed. 相似文献
9.
E Ierardi A Amoruso T La Notte R Francavilla S Castellaneta E Marrazza RA Monno A Francavilla 《Canadian Metallurgical Quarterly》1998,43(12):2733-2737
With the aim of investigating a possible relationship between "objective" halitosis (established by sulfide levels in the breath) and Helicobacter pylori, we performed a study in 58 dyspeptic patients reported to suffer from "bad breath." Furthermore, we evaluated the effects on halitosis of eradication therapy (only for H. pylori-positive patients) and chlorhexidine antiseptic mouth rinses (in all patients). Sulfide compound assay indicated objective halitosis in 52/58 patients, 30 of whom were positive and 22 negative for H. pylori. In 19/30 eradication by double therapy provoked a decrease to below the cutoff value of sulfide levels in 15. In the other 11 of the 30 subjects, in whom H. pylori positivity persisted, halitosis parameters did not change. Chlorexidine reduced sulfides to below the cutoff value in 16/22 H. pylori-negative patients, but did not provoke any change in the 11 unsuccessfully treated H. pylori-positive subjects. In these, objective halitosis disappeared only after a successful eradication by triple therapy (9/11). Our results show a possible association between halitosis and H. pylori since bacterial eradication may resolve the symptom. Antiseptic mouthwashes may be effective only in absence of H. pylori, when halitosis may be due to oral putrefactive microbial activity. In a small number of subjects the cause and treatment of halitosis need to be clarified. 相似文献
10.
Parsimony pressure, the explicit penalization of larger programs, has been increasingly used as a means of controlling code growth in genetic programming. However, in many cases parsimony pressure degrades the performance of the genetic program. In this paper we show that poor average results with parsimony pressure are a result of "failed" populations that overshadow the results of populations that incorporate parsimony pressure successfully. Additionally, we show that the effect of parsimony pressure can be measured by calculating the relationship between program size and performance within the population. This measure can be used as a partial indicator of success or failure for individual populations. 相似文献