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排序方式: 共有2709条查询结果,搜索用时 250 毫秒
31.
Upma Suneja Carlos Castillo Abiezer Disla Cihangir Buyukgoz Liliana Burdea Yekaterina Sitnitskaya Samuel Agyare Menachem Gold Sergey Prokhorov 《The American journal of emergency medicine》2017,35(10):1586.e1-1586.e2
The incidence of acute flaccid paralysis has been on a declining trend with the global efforts on eradication of polio virus. A few scattered clusters of acute flaccid paralysis associated with pathogens like enterovirus other than polio virus and flaviviruses have recently come to limelight. This is a case of acute onset flaccid paralysis of left upper extremity in a fully immunized 5 year old child in New York. 相似文献
32.
Sergey V. Tokalov Andrij M. Abramyuk Nasreddin D. Abolmaali 《Nutrition and cancer》2013,65(6):795-801
This study specifies the basic principles to selectively kill p53-deficient cells (H1299, FaDu) by taxol and to protect p53 wild type cells (A549) by the prior administration of structurally related flavonoids (apigenin, genistein, and quercetin). Cytotoxic and cytostatic properties of flavonoids were investigated in vitro by flow cytometry and were compared to known anticancer drugs (cisplatin, doxorubicin, etoposide). It was confirmed that doxorubicin induced growth arrest and protected A549 cells from taxol while simultaneously killing or blocking H1299 and FaDu cancer cells. It was found that doxorubicin could be successfully substituted in this way by the isoflavone genistein used at physiologically relevant concentrations. The other compounds analyzed revealed less selectivity (apigenin, cisplatin) or demonstrated higher toxicity (cisplatin, etoposide, and quercetin). We concluded that genistein-based therapy may have antagonistic effects when combined with mitotic poisons. The proposed therapeutic strategy allows protection of p53 wild type cells from taxol and selectively increases apoptosis in p53-deficient cells. This strategy exploits the naturally occurring compound that can be used without significant toxicity in rather high concentrations as present in common diets. 相似文献
33.
Angela Zagatina Nadezhda Zhuravskaya Maxim Kamenskikh Dmitry Shmatov Sergey Sayganov Fausto Rigo 《Ultrasound in medicine & biology》2018,44(7):1402-1410
There is a lack of information on the prognostic value of local high velocity in coronary arteries during echocardiography. The aim of the study described here was to define the prognostic value of local velocity >70?cm/s in the left main, anterior or circumflex artery during echocardiography. There were 412 patients in the prospective study. Death, non-fatal myocardial infarction, acute pulmonary edema, acute coronary syndrome and revascularization were defined as major adverse cardiac events (MACEs). Over 10.5?mo, there were 207 patients with MACEs. Seventeen patients died, 10 had non-fatal acute cardiac events and 184 underwent revascularization. Deaths occurred in patients with high local velocity (6.4% vs. 0%, p?<0.009). Acute cardiac events occurred in 10% versus 0% (p?<0.003). MACEs were observed in 62% versus 0% (p?<0.0000001). Only maximal velocity was an independent prognostic predictor of death (odds ratio?=?1.02, 95% confidence interval: 1.01–1.03, p?<0.02) and MACEs (odds ratio?=?1.04, 95% confidence interval: 1.02–1.05, p?<0.0001). The success rate of coronary artery visualization for at least one segment was 91%. 相似文献
34.
Solving the Faddeev-Merkuriev Equations in Total Orbital Momentum Representation via Spline Collocation and Tensor Product Preconditioning 下载免费PDF全文
Vitaly A. Gradusov Vladimir A. Roudnev Evgeny A. Yarevsky & Sergey L. Yakovlev 《Communications In Computational Physics》2021,30(1):255-287
The computational approach for solving the Faddeev-Merkuriev equations
in total orbital momentum representation is presented. These equations describe a system of three quantum charged particles and are widely used in bound state and scattering calculations. The approach is based on the spline collocation method and exploits
intensively the tensor product form of discretized operators and preconditioner, which
leads to a drastic economy in both computer resources and time. 相似文献
35.
Ravil Sharifulin Alexander Bogachev-Prokophiev Sergey Zheleznev Igor Demin Alexey Pivkin Alexander Afanasyev Alexander Karaskov 《The Journal of thoracic and cardiovascular surgery》2019,157(1):134-141.e3
Objective
Although the Ross procedure provides excellent long-term survival and a high quality of life, its use has been limited to relatively few centers. In this study, we evaluated long-term Ross procedure results in adults to assess the predictors of pulmonary autograft durability.Methods
Between 1998 and 2015, 793 consecutive adult patients underwent the Ross procedure. The total root replacement technique was used in all patients.Results
The early mortality rate was 2.9%. The mean follow-up duration was 6.5 ± 3.2 years, and the 10-year survival rate was 90.4%. Longitudinal mixed-effects ordinal regression identified a combination of bicuspid aortic valve and aortic insufficiency (odds ratio, 2.19; P < .001) as predictors for progression of autograft valve insufficiency at follow-up. The cumulative incidence of autograft reoperations at 10 years was 8.6%. Competing risk regression identified bicuspid aortic valve insufficiency as the independent predictor of autograft reoperation (subdistribution hazard ratio, 2.16; P = .030). Moreover, patients with bicuspid aortic valve and aortic insufficiency had greater increases in annulus (P < .001), sinus (P < .001), and ascending aorta (P < .001) diameters over time.Conclusions
For patients undergoing the Ross procedure, a combination of bicuspid aortic valves and aortic insufficiency is the main risk factor for late autograft dilatation and dysfunction. 相似文献36.
Sergey V. Balashov Eli Mordechai Martin E. Adelson Jack D. Sobel Scott E. Gygax 《Diagnostic microbiology and infectious disease》2014
Lactobacilli play a key role in promoting vaginal health. Depletion of these bacteria is associated with bacterial vaginosis (BV), the most common vaginal disorder. Here we describe the development and laboratory validation of a novel single-tube multiplex TaqMan quantitative polymerase chain reaction (qPCR) assay for the identification and quantitative assessment of the four major vaginal Lactobacillus species: L. crispatus, L. jensenii, L. gasseri, and L. iners. The assay utility was evaluated by the analysis of lactobacilli in non-cultured clinical vaginal swab specimens collected from BV patients and healthy individuals. As confirmed by the assay, L. crispatus, L. jensenii, and to a lesser extent L. gasseri, are common in the vagina of healthy women, whereas L. iners dominance is associated with BV. The major assay limitation was preferential detection of dominant Lactobacillus species in samples with mixed lactobacilli resulting in lower sensitivity for minor species. The multiplex qPCR assay described here is an advance in the detection and quantitation of the major vaginal lactobacilli, potentially facilitating the molecular diagnosis of BV and post-therapy restoration of the vaginal microflora. 相似文献
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39.
Takashi Ohki Sergey V. Mikhailenko Tomomi Arai Shuya Ishii Shin’ichi Ishiwata 《Journal of muscle research and cell motility》2012,33(5):351-358
Baculovirus infection of Sf9 cells at high densities, such as during mid- and late exponential phase, often results in a significant reduction of protein yield per cell, compared to the early exponential phase. Nutrient depletion has been considered as a major cause for the decreased protein yield. In this study, we report that the addition of nutrients (glucose, yeastolate ultrafiltrate, and lactalbumin hydrolysate) and small fraction of fresh medium at time of infection restores the expression level of actin and myosin V?CHMM at late exponential phase (11.3?×?106?cells/ml) to that at early exponential phase (1.0?×?106?cells/ml). The relative yields of actin and myosin V?CHMM were approximately equal at both phases (typically 200?mg of actin and 5?mg of myosin V?CHMM per 1010?cells), i.e., the volumetric yield of proteins from the cell culture at late exponential phase was approximately tenfold higher than at early exponential phase. The functionality of the recombinant actin and myosin V?CHMM was confirmed by measuring the rate of actin polymerization, actin-activated ATPase, and the gliding velocity of actin filaments in an in vitro motility assay. 相似文献
40.
Carsten Nowak Steffen Zuther Sergey V. Leontyev Jutta Geismar 《Conservation Genetics Resources》2014,6(1):159-162
We developed 17 variable microsatellite markers for the threatened Saiga antelope. Using one Illumina Miseq lane resulted in 105,948 unique fragments containing a microsatellite motif. Eighty-one ordered primer pairs resulted in 26 analyzable fragments, of which 17 markers showed variability in at least one population from Kazakhstan. Number of alleles ranged from 2 to 11 and values of heterozygosity varied from 0.08 to 0.91 (HO) and 0.08 to 0.88 (HE). The markers are currently used to delineate conservation units and to help understanding annual migration dynamics in this species. 相似文献