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71.
Moderate and severe reactions in blood donors 总被引:2,自引:0,他引:2
During the period April 1985 to March 1986, 217 blood donors were found to have moderate (syncopal) to severe (convulsive) reactions. This population was compared to 5630 randomly selected donors who did not have reactions. An examination of demographic, physical, and societal/emotional factors was conducted to determine if any were predictive of reactions in donors. The results of the research supported the hypothesis that first-time donors have a higher frequency of reactions (1.7%) than do repeat donors (0.19%). A review of the above predictive factors documented that, with regard to demographic factors, 1) the number of prior donations was inversely proportional to the risk of reaction; 2) the gender of the donor was not predictive; and 3) youth was a predictor of reactions. An analysis of the physical factors revealed that donors who reacted were of lower weight (mean, 153.7 lb) than those who did not (mean, 166.4 lb) and that systolic blood pressure was slightly lower in the group with reactions. Although the difference was significant (3 torr), it was not thought to be significant clinically. In a comparison of a group with systolic blood pressure ranging from 80 to 100 torr and a group with systolic blood pressure ranging from 120 to 140 torr, the first group had a 70-percent higher risk of reaction. Finally, with regard to the last category of societal or emotional factors, the research demonstrates 1) that the ingestion of caffeinated beverages was associated with a reduced risk of reactions; 2) that the food intake of donors who reacred was significantly different from that of those who had no reaction, but this difference was not thought to be clinically significant; and 3) that the duration between registration and the onset of phlebotomy was directly predictive of reaction status. The research indicates that first-time donor status and several specific demographic, physical, and societal or emotional factors are predictors of donor reactions. 相似文献
72.
J Williams DCH FRCP KA Richards MSc UK Study Group 《International journal of clinical practice》1997,51(3):147-153
A total of 323 children aged 4-11 years who were receiving, or had symptoms indicating a clinical requirement for, inhaled corticosteroid at a daily dose of 400 μg budesonide (BUD) or beclomethasone dipropionate (BDP), or 200 μg fluticasone propionate (FP), were randomised into this multicentre, open-label, parallel group study. Patients received either FP 100 μg b.d. administered via the Accuhaler/Diskus inhaler (n=159) or BUD 200 μg b.d. administered via a Turbohaler inhaler (n=164) for four weeks and recorded daily their morning and evening peak expiratory flow (PEF), asthma symptoms and use of relief medication. Device handling was assessed by a questionnaire, with responses recorded on three- or five-point ordinal scales. The primary efficacy parameter was mean percent predicted morning PEF. The device handling results showed the Accuhaler/Diskus inhaler was rated more favourably than the Turbohaler inhaler in terms of ease of correct inhaler use, ease of telling how many doses were left, ease of knowing whether a dose had been inhaled and overall liking of the device. More patients in the Accuhaler/Diskus group (85%) than in the Turbohaler group (58%) said they would be happy to receive the same device again, while 8% and 25% respectively said they would not be happy to be given it again. In addition, the change from baseline to week 4 of treatment in mean percent predicted morning PEF was greater in the FP Accuhaler/Diskus group, indicating that FP 200 μg daily via Accuhaler/Diskus inhaler is at least as clinically effective as BUD 400 μg daily via the Turbohaler inhaler. 相似文献
73.
74.
Monnin P Marshall NW Bosmans H Bochud FO Verdun FR 《Physics in medicine and biology》2011,56(14):4221-4238
Assessment of image quality for digital x-ray mammography systems used in European screening programs relies mainly on contrast-detail CDMAM phantom scoring and requires the acquisition and analysis of many images in order to reduce variability in threshold detectability. Part II of this study proposes an alternative method based on the detectability index (d') calculated for a non-prewhitened model observer with an eye filter (NPWE). The detectability index was calculated from the normalized noise power spectrum and image contrast, both measured from an image of a 5 cm poly(methyl methacrylate) phantom containing a 0.2 mm thick aluminium square, and the pre-sampling modulation transfer function. This was performed as a function of air kerma at the detector for 11 different digital mammography systems. These calculated d' values were compared against threshold gold thickness (T) results measured with the CDMAM test object and against derived theoretical relationships. A simple relationship was found between T and d', as a function of detector air kerma; a linear relationship was found between d' and contrast-to-noise ratio. The values of threshold thickness used to specify acceptable performance in the European Guidelines for 0.10 and 0.25 mm diameter discs were equivalent to threshold calculated detectability indices of 1.05 and 6.30, respectively. The NPWE method is a validated alternative to CDMAM scoring for use in the image quality specification, quality control and optimization of digital x-ray systems for screening mammography. 相似文献
75.
Marshall NW Monnin P Bosmans H Bochud FO Verdun FR 《Physics in medicine and biology》2011,56(14):4201-4220
In many European countries, image quality for digital x-ray systems used in screening mammography is currently specified using a threshold-detail detectability method. This is a two-part study that proposes an alternative method based on calculated detectability for a model observer: the first part of the work presents a characterization of the systems. Eleven digital mammography systems were included in the study; four computed radiography (CR) systems, and a group of seven digital radiography (DR) detectors, composed of three amorphous selenium-based detectors, three caesium iodide scintillator systems and a silicon wafer-based photon counting system. The technical parameters assessed included the system response curve, detector uniformity error, pre-sampling modulation transfer function (MTF), normalized noise power spectrum (NNPS) and detective quantum efficiency (DQE). Approximate quantum noise limited exposure range was examined using a separation of noise sources based upon standard deviation. Noise separation showed that electronic noise was the dominant noise at low detector air kerma for three systems; the remaining systems showed quantum noise limited behaviour between 12.5 and 380 μGy. Greater variation in detector MTF was found for the DR group compared to the CR systems; MTF at 5 mm(-1) varied from 0.08 to 0.23 for the CR detectors against a range of 0.16-0.64 for the DR units. The needle CR detector had a higher MTF, lower NNPS and higher DQE at 5 mm(-1) than the powder CR phosphors. DQE at 5 mm(-1) ranged from 0.02 to 0.20 for the CR systems, while DQE at 5 mm(-1) for the DR group ranged from 0.04 to 0.41, indicating higher DQE for the DR detectors and needle CR system than for the powder CR phosphor systems. The technical evaluation section of the study showed that the digital mammography systems were well set up and exhibiting typical performance for the detector technology employed in the respective systems. 相似文献
76.
Background
The burden of lymphomas on the health care system in Nigeria is enormous. Correct diagnosis and identification of aetiological factor are important steps in reducing this burden.Methods
Eight cases diagnosed as HL within a period of six years at the Obafemi Awolowo University teaching Hospital, Ile-Ife, Nigeria by haematoxylin and eosin (Hand E) only were immunophenotyped using the indirect immunoperoxidase method. Epstein-Barr virus latent membrane protein-1 (LMP-1), CD15 and CD30 immunohistochemistry was also performed. The clinical characteristics of each patient were documented.Objectives
To document the frequency of involvement of Epstein-Barr virus in cases of HL seen in a university hospital in Nigeria.Results
Out of the eight cases diagnosed by H&E as HL immunophenotyping showed only five were HL. The rest were non-Hodgkin''s lymphoma (2 diffuse large B-cell and 1 null cell ALCL). All were cases of classical HL with 60% being of the mixed cellularity (MC) subtype. There were 2 males and 3 females with ages ranging from 7 years to 40 years. All presented with cervical lymphadenopathy and three had splenomegaly in addition. 60% of the tumour was EBV positive, all of the MC subtype. Three patients had chemotherapy. Eventually all were lost to follow-up. There was no case of the nodular lymphocyte predominance variant.Conclusion
Mixed cellularity is the most common subtype and is the only subtype associated with EBV positivity in this study. Epstein-Barr virus probably plays an important role in the aetiology of HL in Nigerians.Running title: Epstein-Barr virus, Hodgkin''s lymphoma in Nigerians 相似文献77.
We report a patient with a clinical and molecular diagnosis of LEOPARD syndrome (LS) associated with multiple granular cell tumors (MGCT). Bidirectional sequencing of exons 7, 12, and 13 of the PTPN11 gene revealed the T468M missense mutation in exon 12. This mutation has been previously reported in patients with LS. To our knowledge, this is the first report of MGCT associated with molecularly characterized LS and provides the first molecular evidence linking granular cell tumors (GCT) to the Ras/mitogen-activated protein (MAP) kinase pathway. We propose that MGCT can be associated with LS. Analysis of GCT from this case tested negatively for loss of heterozygosity (LOH) at the PTPN11 and NF1 loci and did not show deletions of the PTEN gene. The absence of LOH of PTPN11 supports published functional data that T468M is a dominant-negative mutation. 相似文献
78.
R Rodríguez-Rodríguez P Yarova P Winter KA Dora 《British journal of pharmacology》2009,158(6):1609-1620
Background and purpose:
Extracellular nucleotides play a crucial role in the regulation of vascular tone and blood flow. Stimulation of endothelial cell P2Y1 receptors evokes concentration-dependent full dilatation of resistance arteries. However, this GPCR can desensitize upon prolonged exposure to the agonist. Our aim was to determine the extent and nature of P2Y1 desensitization in isolated and pressurized rat small mesenteric arteries.Experimental approach:
The non-hydrolyzable selective P2Y1 agonist ADPβS (3 µM) was perfused through the lumen of arteries pressurized to 70 mmHg. Changes in arterial diameter and endothelial cell [Ca2+]i were obtained in the presence and absence of inhibitors of protein kinase C (PKC).Key results:
ADPβS evoked rapid dilatation to the maximum arterial diameter but faded over time to a much-reduced plateau closer to 35% dilatation. This appeared to be due to desensitization of the P2Y1 receptor, as subsequent endothelium-dependent dilatation to acetylcholine (1 µM) remained unaffected. Luminal treatment with the PKC inhibitors BIS-I (1 µM) or BIS-VIII (1 µM) tended to augment concentration-dependent dilatation to ADPβS (0.1–3 µM) and prevented desensitization. Another PKC inhibitor, Gö 6976 (1 µM), was less effective in preventing desensitization. Measurements of endothelial cell [Ca2+]i in pressurized arteries confirmed the P2Y1 receptor but not M3 muscarinic receptor desensitization.Conclusions and implications:
These data demonstrate for the first time the involvement of PKC in the desensitization of endothelial P2Y1 receptors in pressurized rat mesenteric arteries, which may have important implications in the control of blood flow by circulating nucleotides. 相似文献79.
80.
Colombani S Kabbani Y Mathoulin-Pélissier S Gékière JP Dixmérias F Monnin D Lakdja F 《Annales fran?aises d'anesthèsie et de rèanimation》2008,27(3):202-207