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排序方式: 共有357条查询结果,搜索用时 15 毫秒
41.
Brosh D Assali A Vaknin-Assa H Fuchs S Teplitsky I Shor N Kornowski R 《International journal of cardiovascular interventions》2005,7(4):183-187
The ACIST injection system is an automatic power injection device that allows for online control of injection rate and volume of contrast. Limited data is available whether this technology allows reducing use of contrast and fluoroscopy time. Accordingly, we compared the use of this system to manual injection among 450 consecutive patients who underwent diagnostic coronary angiography and/or angioplasty who were randomly assigned to either manual contrast injection (control; n=198) or to the ACIST system (study group; n=252). The amount of contrast, fluoroscopy and total procedural times were recorded for each patient. In the diagnostic group, the mean total amount of contrast (including wasted) was reduced by 63% when the ACIST was used compared to control (100+/-42 ml versus 163+/-56 ml; P<0.001, respectively). When only the net amount of contrast delivered to the patient was considered, the differences were smaller (20%, P=0.004). During angioplasty, the amount of contrast was also lower in the ACIST group (206+/-65 versus 230+/-69, P=0.008), whereas no difference were noted in net amount of contrast. Fluoroscopy time was significantly shorter in the ACIST group compared to control both during diagnostic catheterization (4.7+/-3.5 min versus 6.3+/-5.5 min, respectively; P=0.014), and angioplasty (16.7+/-9.1 min versus 19.6+/-12.4 min, respectively; P=0.05). Routine utilization of the ACIST system during diagnostic and interventional procedure significantly reduced the total amount of contrast media used and fluoroscopy time. 相似文献
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43.
L Abo Assali A Al-Mariri E Hamad AQ Abbady 《World journal of microbiology & biotechnology》2012,28(10):2987-2995
Brucella has a great impact on health and economy in Syria, thus much effort is being placed on the development of diagnostics and vaccines. In this context, a wide Nanobody "immune" library was previously established, from which several Brucella-specific binders were isolated. One of these camel genetically engineered heavy-chain antibody fragments was referred to as NbBruc02. The precise antigen of NbBruc02 was presumed to be, according to proteomic approaches, the Brucella heat shock protein of 60?kDa (HSP-60). HSP-60, or alternatively named GroEL, is an interesting Brucella immunodominant antigen with important roles in the parasite life cycle, mainly adhesion and penetration during the infection of macrophages. In the present work, the capacity of NbBruc02 to filtrate the native GroEL from Brucella total extract was tested by immunochromatography approach. The interaction between NbBruc02 and its antigen was further confirmed using recombinant GroEL from Brucella. Interestingly, NbBruc02 was able to immunodetect the native as well as the denatured forms of the rGroEL in ELISA and immunoblotting, respectively. In agreement with previously reported data, NbBruc02 was able only to detect the denatured Yersinia rGroEL. Using surface plasmon resonance (SPR) biosensor, NbBruc02 showed a strong interaction, with nanomolar affinity (K (D)?=?~10(-8)?M), with the native rGroEL of Brucella and not of Yersinia. Because the casual conformational changes in the GroEL 3D structure make the base of its function, NbBruc02 by its ability to recognize a "conformational epitope," could open wide perspectives to study the role of GroEL in Brucella physiology. 相似文献
44.
Neghal Kandiyil Nishath Altaf Akram A. Hosseini Shane T. MacSweeney Dorothee P. Auer 《PloS one》2012,7(10)
Background and Purpose
Women are at lower risk of stroke, and appear to benefit less from carotid endarterectomy (CEA) than men. We hypothesised that this is due to more benign carotid disease in women mediating a lower risk of recurrent cerebrovascular events. To test this, we investigated sex differences in the prevalence of MRI detectable plaque hemorrhage (MRI PH) as an index of plaque instability, and secondly whether MRI PH mediates sex differences in the rate of cerebrovascular recurrence.Methods
Prevalence of PH between sexes was analysed in a single centre pooled cohort of 176 patients with recently symptomatic, significant carotid stenosis (106 severe [≥70%], 70 moderate [50–69%]) who underwent prospective carotid MRI scanning for identification of MRI PH. Further, a meta-analysis of published evidence was undertaken. Recurrent events were noted during clinical follow up for survival analysis.Results
Women with symptomatic carotid stenosis (50%≥) were less likely to have plaque hemorrhage (PH) than men (46% vs. 70%) with an adjusted OR of 0.23 [95% CI 0.10–0.50, P<0.0001] controlling for other known vascular risk factors. This negative association was only significant for the severe stenosis subgroup (adjusted OR 0.18, 95% CI 0.067–0.50) not the moderate degree stenosis. Female sex in this subgroup also predicted a longer time to recurrent cerebral ischemic events (HR 0.38 95% CI 0.15–0.98, P = 0.045). Further addition of MRI PH or smoking abolished the sex effects with only MRI PH exerting a direct effect.Meta-analysis confirmed a protective effect of female sex on development of PH: unadjusted OR for presence of PH = 0.54 (95% CI 0.45–0.67, p<0.00001).Conclusions
MRI PH is significantly less prevalent in women. Women with MRI PH and severe stenosis have a similar risk as men for recurrent cerebrovascular events. MRI PH thus allows overcoming the sex bias in selection for CEA. 相似文献45.
46.
Sexuality in fungi has long been a matter of concerns and debates that always necessitated extensive analysis of the relationship between organisms assumed to represent different developmental forms of the same organism. Moreover, mating-virulence correlation and the growing worry of opportunistic fungal infections in immunocompromised states associated with AIDS, cancer chemotherapy and organ transplantation protocols have been critically addressed nowadays. In view of that, we genetically characterized Aspergillus chevalieri, Aspergillus nidulans, Aspergillus tetrazonus (quadrilineatus) and their teleomorphs with RAPD analysis using 5'-d[AACGCGCAAC]-3' and 5'-d[CCCGTCAGCA]-3' primers. The reported similarities between the sexual and the asexual forms of the tested species, using Dice coefficient, ranged between 40% and 70% which holds pretty much with the current systematics of the genus. The study presents a rapid consistent method for identification of A. chevalieri, A. nidulans, A. tetrazonus (quadrilineatus) and their teleomorphs based on the banding pattern of RAPD-generated fragments that can be reliably used ahead of further applications on these species. 相似文献
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48.
Akram Khan Mansour Qurashi Kim Kwiatkowski Don Cates Henrique Rigatto 《Journal of applied physiology》2005,98(4):1171-1176
We measured the PCO2 apneic threshold in preterm and term infants. We hypothesized that, compared with adult subjects, the PCO2 apneic threshold in neonates is very close to the eupneic PCO2, likely facilitating the appearance of periodic breathing and apnea. In contrast with adults, who need to be artificially hyperventilated to switch from regular to periodic breathing, neonates do this spontaneously. We therefore measured the apneic threshold as the average alveolar PCO2 (PaCO2) of the last three breaths of regular breathing preceding the first apnea of an epoch of periodic breathing. We also measured the PaCO2 of the first three breaths of regular breathing after the last apnea of the same periodic breathing epoch. In preterm infants, eupneic PaCO2 was 38.6 +/- 1.4 Torr, the preperiodic PaCO2 apneic threshold was 37.3 +/- 1.4 Torr, and the postperiodic PaCO2 was 37.2 +/- 1.4 Torr. In term infants, the eupneic PaCO2 was 39.7 +/- 1.1 Torr, the preperiodic PaCO2 apneic threshold was 38.7 +/- 1.0 Torr, and the postperiodic value was 37.9 +/- 1.2 Torr. This means that the PaCO2 apneic thresholds were 1.3 +/- 0.1 and 1.0 +/- 0.2 Torr below eupneic PaCO2 in preterm and term infants, respectively. The transition from eupneic PaCO2 to PaCO2 apneic threshold preceding periodic breathing was accompanied by a minor and nonsignificant increase in ventilation, primarily related to a slight increase in frequency. The findings suggest that neonates breathe very close to their PCO2 apneic threshold, the overall average eupneic PCO2 being only 1.15 +/- 0.2 Torr (0.95-1.79, 95% confidence interval) above the apneic threshold. This value is much lower than that reported for adult subjects (3.5 +/- 0.4 Torr). We speculate that this closeness of eupneic and apneic PCO2 thresholds confers great vulnerability to the respiratory control system in neonates, because minor oscillations in breathing may bring eupneic PCO2 below threshold, causing apnea. 相似文献
49.
Kafeel Ahmad Asma Ashfaq Muhammad Ashraf Nudrat Aisha Akram Sumaira Yasmin 《人类与生态风险评估》2016,22(3):597-610
Levels of Mo, As, Se, Fe, Cu, Zn, Ni, and Pb were determined in a vegetable commonly consumed in Pakistan. Samples were collected from three different sites (Ratokala, Phularwan, and Mailowal) supplied with three different water sources. Mo and Pb in water and Mo and As in C. sativum were higher than the suggested standards at the international level. Lower bioconcentration factor and pollution load index were seen at Site-I than at other sites. A positive association was found between the rhizosphere metals and those of the vegetable at all three sites. Enrichment factor at three sites ranged from 0.28 to 10.39. The highest value of daily intake of metals was found for Fe (0.245 mg/kg/day) and of the health risk index for As (70.41) at the wastewater inundated site. It is inferred that uptake of Mo, As, Cu, Ni, and Pb through C. sativum represents a high health danger to the individuals using this vegetable. 相似文献
50.
Adeel Khan Munir Ahmad Mukhtar Ahmed Kulvinder Singh Gill Zahid Akram 《Saudi Journal of Biological Sciences》2021,28(12):7404-7415
Terminal heat stress causes irreversible damage to wheat crop productivity. It reduces the vegetative growth and flowering period that consequently declines the efficiency to capture available stem reserves (carbohydrates) in grains. Markers associated with thermotolerant traits ease in marker assisted selection (MAS) for crop improvement. It identifies the genomic regions associated with thermotolerant traits in wheat, but the scarcity of markers is the major hindrance in crop improvement. Therefore, 158 wheat genotypes were subjected to genotyping with 165 simple sequence repeat markers dispersed on three genomes (A, B and D). Allelic frequency and polymorphic information content values were highest on genome A (5.34 (14% greater than the lowest value at genome D) and 0.715 (3% greater than the lowest value at genome D)), chromosome 4 (5.40 (16% greater than the lowest value at chromosome 2) and 0.725 (5% greater than the lowest value at chromosome 6)) and marker xgwm44 (13.0 (84% greater than the lowest value at marker xbarc148) and 0.916 (46% greater than the lowest value at marker xbarc148)). Bayesian based population structure discriminated the wheat genotypes into seven groups based on genetic similarity indicating their ancestral origin and geographical ecotype. Linkage disequilibrium pattern had highest significant (P < 0.001) linked loci pairs 732 on genome A at r2 > 0.1 whereas, 58 on genome B at r2 > 0.5. Linkage disequilibrium decay (P < 0.01 and r2 > 0.1) had larger LD block (5–10 cM) on genome A. Highly significant MTAs (P < 0.000061) under heat stress conditions were identified for flag leaf area (xwmc336), spikelet per spike (xwmc553), grains per spike (cxfa2147, xwmc418 and xwmc121), biomass (xbarc7) and grain yield (xcfa2147 and xwmc671). The identified markers in this study could facilitate in MAS and gene pyramiding against heat stress in wheat. 相似文献