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261.
The main protective antigen of the causative agent of plague is capsular antigen F1. The preparations of this antigen isolated from Y.pestis strain EV are characterized by a high content of polysaccharide chains of endotoxins. This can be avoided by using R-variants of bacteria as producers. In this work the comparative study of the preparations of antigen F1 obtained from Y.pestis strain EV, Escherichia coli producer strain HB101 pFS1 with the complete structure of LPS and Salmonella minnesota producer strain Re595 pFS1 with maximally reduced LPS has been made. As revealed in this study, the physico-chemical properties of these preparations (the isoelectric point, electrophoretic mobility, the molecular weight of subunits) are identical. The preparation of antigen F1 obtained from S.minnesota has been found to give the highest yield and to have the lowest content of polysaccharide admixtures. This preparation has proved to possess the maximal protective potency, which may be linked with the adjuvant and immunogenic activity of microadmixtures of glycolipid Re, contained in F1.  相似文献   
262.
The heat exchange in cryostat throats with coaxial extension elements is investigated theoretically and experimentally. It is shown that the efficiency of the coaxial element falls sharply when its length is increased.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 36, No. 6, pp. 991–996, June, 1979.  相似文献   
263.
The Authors report the result of their ten-years experience with femoro-femoral crossover bypass in 26 patients affected with unilateral occlusion of the iliac artery. This bypass is an easy and quick procedure, useful in both short and long term. The patency rate after 58 months is 84.6%. Thus, its use indicated in a high number of patients, not only for a limb salvage treatment of a disabling claudication. The indications for this bypass can be extended to low surgical risk subjects, and it does not have to be considered only for the high-risk patients, instead of major surgery procedure on the aorto-iliac axis. The minimal necessary conditions of the limbs for performing the femoro-femoral crossover bypass are a pressure gradient of 35 mmHg and the angiographical demonstration of the unilateral occlusion. If the contralateral axis appears patent, but there are also multiple atherosclerotic sites, we consider other bypasses as therapeutical choices: aorto-bifemoral, ilio-femoral and the femoro-femoral cross-over itself; in the latter case we previously perform a transluminal angioplasty or an endarterectomy of the donor iliac artery. In these situations is essential to evaluate of the benefit/risk rate for every single patient.  相似文献   
264.
265.
BACKGROUND: To validate basal glucemia as a control method for non-insulin dependent diabetes mellitus, and to determine the cut-off point that best characterizes good control. PATIENTS AND METHODS: A transversal, observational study of 256 patients who participated in a diabetes mellitus follow-up program during 1993. In the study, glucemia validity indicators were evaluated after making 2 X 2 tables and ROC (receiver operating characteristic) curves for the different values. Control values of glycated hemoglobin was used as to define a good (< 6.5%) and moderate (< 8%). RESULTS: The values of glucemia considered to be "good" as regards control (from 80 to 110 mg/dl, 4.4-6.05 mmol/dl) have good sensitivity (from 97.3% to 100%) and negative predictive values (from 85.7% to 100%) but extremely bad specificity (from 3.8% to 22.7%) and only moderate positive predictive values (from 59.5% to 64.1%) in reference to values of glycated hemoglobin of 6.5%. The same occurs for 8% as regards sensitivity (from 98.6% to 100%), negative predictive value (from 96.4% to 100%) and specificity from 2.1% to 14.5%). Positive predictive value worsens (from 27.8% to 30.3%). The most effective and most accurate values of glucemia in the ROC curves are 150 mg/dl (8.25 mmol/l) if the control of glycated hemoglobin is good, and 170 mg/dl (9.35 mmol/l) if it is moderate. CONCLUSIONS: The glucemia control figures recommended by consensus produce false positives when they are compared to glycated hemoglobin. In the analysis of effectiveness and ROC curves greater accuracy is obtained with glucemia values that are slightly higher than those recommended.  相似文献   
266.
SputnikV is a vaccine against SARS-CoV-2 developed by the Gamaleya National Research Centre for Epidemiology and Microbiology. The vaccine has been shown to induce both humoral and cellular immune responses, yet the mechanisms remain largely unknown. Forty SputnikV vaccinated individuals were included in this study which aimed to demonstrate the location of immunogenic domains of the SARS-CoV-2 S protein using an overlapping peptide library. Additionally, cytokines in the serum of vaccinated and convalescent COVID-19 patients were analyzed. We have found antibodies from both vaccinated and convalescent sera bind to immunogenic regions located in multiple domains of SARS-CoV-2 S protein, including Receptor Binding Domain (RBD), N-terminal Domain (NTD), Fusion Protein (FP) and Heptad Repeats (HRs). Interestingly, many peptides were recognized by immunized and convalescent serum antibodies and correspond to conserved regions in circulating variants of SARS-CoV-2. This breadth of reactivity was still evident 90 days after the first dose of the vaccine, showing that the vaccine has induced a prolonged response. As evidenced by the activation of T cells, cellular immunity strongly suggests the high potency of the SputnikV vaccine against SARS-CoV-2 infection.  相似文献   
267.
The microscopic fungi Eremothecium ashbyi and E. gossypii are known for their ability to synthetize essential oil, which has a composition similar to that of rose oil. The development of Eremothecium oil technology enables the production of rose-scented products, which are demanded by pharmaceutical, food, and perfumery industries. This study focuses on assessing the in vitro cytotoxicity of Eremothecium oil, in comparison with that of rose oil, using a combination of methods and two cell types (3T3 mouse fibroblast cell line and bone-marrow-derived mesenchymal stromal cells (BM-MSCs)). The Eremothecium oil samples possessed cytotoxic effects that varied among strains and batches. The revealed cytotoxicity level may be used to tailor the qualitative and quantitative composition of Eremothecium oil to achieve a particular quality in its end products. These results require further analysis using other cell types and assays based on measuring other cell functions.  相似文献   
268.
Powder Metallurgy and Metal Ceramics - The synthesized silver-substituted tricalcium phosphate powder has been studied by infrared spectroscopy and X-ray diffraction. The plasma deposition of...  相似文献   
269.
The use of SCAPs – short-chained alkyl phenols – as industrial fingerprints and as process- and transport-indicators in groundwater is based on their environmental behaviour. The chemical and physical properties have to be different enough between each compound in order to observe fractionation during transport. Water solubility is high for phenols and decreases with the amount of alkylation. The partitioning coefficients logKOW and logKOW for phenols are very small and increase with growing degrees of alkylation. This leads to fractionation of the compounds within the aquifer, which was demonstrated in a field study. In spite of limited literature data on toxicity and degradability for some SCAP compounds, natural attenuation is still a possible remediation technique. Overall, the environmental behaviour of SCAPs indicates that they are mobile in aquifers. This creates opportunities for new applications such as their use as process- and transport-indicators in the assessment of contaminated sites.  相似文献   
270.
正3月1~3日,第44届Mido(米兰国际眼镜展)在意大利米兰Fiera Milano展馆如期举行。本届米兰展依然是6个展馆,但是为了更利于买家参观,组委会将传统的双展馆设计合为一个馆:空气流通性更好,展馆功能性更强,展览场地的利用也更充分。其中,汇聚了世界知名眼镜品牌的  相似文献   
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