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991.
Objectiveto pilot the Optimality Index-US (OI-US) for the first time within a UK maternity setting in a sample of women at mixed risk.Designa multidisciplinary group reviewed the items and evidence base of the OI-US. A pilot study was undertaken to compare the availability and quality of data from maternity records to complete the OI-US. Data were collected from maternity records.Settinga maternity unit of an inner city teaching hospital in England.Participantsclinical midwives, research midwives, midwifery lecturers and consultant obstetricians (n=10) reviewed the items and evidence base of the OI-US. Data were collected from the maternity records of 97 women receiving caseload care and 103 women receiving standard care.Measurements and findingswhen the multidisciplinary group reviewed the items and evidence base of the OI-US, it was noted that some social and clinical factors should be considered for inclusion as part of the Perinatal Background Index (PBI) and OI. The results suggest that the inclusion of women at higher risk in this sample within the UK maternity setting has not been captured by the OI-US.Key conclusionsthe following social and clinical factors should be included as part of the PBI and OI for the UK setting: measure of social deprivation, woman's ability to speak and understand English in relation to accessing maternity care, mental health problems during pregnancy and history of domestic violence during pregnancyImplications for practiceavailability of items in electronic records is poor and it is recommended that the OI-UK version is a useful research tool in prospective data collection. The development of an international version would be valuable for comparision of background risk and outcomes across a range of care settings.  相似文献   
992.
This study investigated the association between religious beliefs and opinions on xenotransplantation among students from three different countries. A lower proportion of religious students accepted xenotransplantation than did non-religious students. A higher proportion of Protestant students seemed to accept xenotransplantation than did Muslim and Roman Catholic students. A higher proportion of the religious respondents had not formed an opinion on xenotransplantation compared to non-religious students. There was no difference according to gender on views on xenotransplantation, but a higher proportion of older students seemed to accept xenotransplantation than did younger students. A higher proportion of non-vegetarians reported acceptance of xenotransplantation than did vegetarians. Acceptance of xenotransplantation was higher in Sweden compared to the two other regions, and the proportion of students who had formed an opinion was higher as well.  相似文献   
993.
OBJECTIVE: to compare and contrast competencies of midwives with single or dual qualifications at the point of registration in Scotland. DESIGN: self-completing survey using the Glasgow Royal Maternity Hospital's Skills' Inventory by midwives at the point of registration and by Supervisors of Midwives analysed using non-parametric statistical tests. Content analysis of semi-structured interviews with experienced midwives and Supervisors of Midwives. SETTING: midwifery education and practice settings throughout Scotland. PARTICIPANTS: 157 midwives at the point of registration, 166 Supervisors of Midwives. MEASUREMENTS: Mann-Whitney and Kruskal Wallis analysis of skills of midwives at the point of registration in prenatal, labour, post-natal, neonatal areas and extended skills areas. FINDINGS/IMPLICATIONS FOR PRACTICE: all newly qualified midwives in Scotland, regardless of their educational preparation, are capable of providing care for women and babies in normal midwifery situations. While support for the direct entry programmes has been clearly demonstrated, this is not unanimous, although as more direct entry midwives take up positions, attitudes are becoming more positive.  相似文献   
994.
The ability to predict clinical image quality from physical measures is useful for optimization in diagnostic radiology. In this work, clinical and physical assessments of image quality are compared and correlations between the two are derived. Clinical assessment has been made by a group of expert radiologists who evaluated fulfillment of the European image criteria for chest and lumbar spine radiography using two scoring methods: image criteria score (ICS) and visual grading analysis score (VGAS). Physical image quality measures were calculated using a Monte Carlo simulation model of the complete imaging system. This model includes a voxelized male anatomy and was used to calculate contrast and signal-to-noise ratio of various important anatomical details and measures of dynamic range. Correlations between the physical image quality measures on the one hand and the ICS and VGAS on the other were sought. 16 chest and 4 lumbar spine imaging system configurations were compared in frontal projection. A statistically significant correlation with clinical image quality was found in chest posteroanterior radiography for the contrast of blood vessels in the retrocardiac area and a measure of useful dynamic range. In lumbar spine anteroposterior radiography, a similar significant correlation with clinical image quality was found between the contrast and signal-to-noise ratio of the trabecular structures in the L1-L5 vertebrae. The significant correlation shows that clinical image quality can, at least in some cases, be predicted from appropriate measures of physical image quality.  相似文献   
995.
PURPOSE: This study aimed to investigate redox regulation of the proteasome as well as the effect of proteasome inhibition on intracellular oxidative status and apoptosis. METHODS: Oxidative stress was induced in cultured human lens epithelial cells (HLECs) and intact mouse lenses by 100 microM H2O2. HLECs were also exposed to the reduced and the oxidized forms of glutathione (GSH/GSSG) and the reducing agent dithiotreitol (DTT). The chymotrypsin-like, the trypsin-like, and the peptidylglutamyl peptidase activities of the proteasome were measured using synthetic fluorogenic substrates. Superoxide as well as peroxide production, mitochondrial membrane potential, and the level of GSH was measured in HLECs after proteasome inhibition by MG-132 or lactacystin. Apoptosis was determined by measuring caspase-3 activation and by studying apoptotic nuclei after staining with Hoechst 33342. RESULTS: All three peptidase activities of the proteasome were inhibited by 100 microM H2O2 and by the oxidized form of glutathione (GSSG), whereas the reduced form (GSH) stimulated chymotrypsin-like and peptidylglutamyl peptidase activities in HLECs lysates. Intact mouse lenses exposed to 100 microM H2O2 exhibited loss of transparency and trends of decreased chymotrypsin-like proteasome activity as well as decreased GSH levels. Inhibition of the proteasome in cultured HLECs caused significant increase in apoptosis and disturbed intracellular redox balance. Simultaneous addition of exogenous GSH completely abolished the increased apoptosis seen after MG-132 treatment. CONCLUSIONS: This study supports the hypothesis that intracellular proteolytic and oxidative regulatory systems are tightly coupled. The current data also indicate that apoptosis by proteasome inhibition is mediated through oxidative mechanisms.  相似文献   
996.
997.
Background  Alopecia areata (AA) is an immune-mediated form of hair loss that occurs in all ethnic groups, ages, and both sexes. Helicobacter pylori has been associated with certain extra-digestive dermatological conditions, including chronic urticaria, rosacea, Schönlein-Henoch purpura, Sweet syndrome, systemic sclerosis, and atopic dermatitis.
Objective  The causal relation between alopecia areata and H. pylori is discussed. We have screened for the presence of H. pylori in patients with AA in order to determine any potential role in its pathophysiology.
Patients and methods  We have prospectively studied 31 patients with AA and 24 healthy volunteers of similar gender for the presence of H. pylori surface antigen (HpSag) in stool.
Results  Optical density values for H. pylori infection were positive in 18 of all 31 patients evaluated (58.1%), while in 13 patients, values did not support H. pylori infection (41.9%). While in the control group, 10 of 24 (41.7%) had positive results. Within the group of AA, there was no significant difference between HpSag-positive and HpSag-negative patients.
Conclusions  Based on these results, the relation between H. pylori and AA is not supported. We advise that H. pylori detection should not be included in the laboratory workup of AA.  相似文献   
998.
Microembolization is common after coronary interventions, and therefore this MRI study aimed to quantify the effect of coronary microembolization on left ventricular (LV) function. The left anterior descending artery (LAD) was selectively catheterized in an XMR suite (Philips Medical Systems, Best, The Netherlands) in eight pigs to deliver MR contrast media to measure the LAD territory using first‐pass perfusion and for intracoronary delivery of the embolic agent. Cine, tagged, and delayed contrast‐enhanced MRI (DCE‐MRI) was performed to assess LV volumes, ejection fraction, radial and circumferential strain, and viability at baseline, 1 h, and 1 week after microembolization. Histopathology and histochemical staining were used to characterize and measure the extent of microinfarction. The LAD territory was 35% ± 2% LV mass. Patchy microinfarction on DCE‐MRI at 1 week was 22.0% ± 3.6% LAD territory (7.5% LV mass). Microembolization caused persistent decline in ejection fraction (baseline = 49% ± 1%, 1 h = 29% ± 1%, P = 0.02 and 1 week = 36% ± 1%, P = 0.03) and increased end‐diastolic (79.6 ± 3.9 ml, 85.5 ± 4.5 ml, P = 0.03 and 92.4 ± 6.2 ml, P = 0.06, respectively) and end‐systolic (40.8 ± 2.1 ml, 60.2 ± 3.4 ml, P = 0.02 and 59.3 ± 4.8 ml, P = 0.03, respectively) volumes. The microembolized territory was manifested as dysfunctional regions for 1 week on cine and tagged MRI. Histopathology revealed occlusive microemboli surrounded by necrotic tissue undergoing repair. Microinfarction was visualized after coronary microembolization and caused LV dysfunction disproportionate to the size of myocardial damage. It also changed LV geometry and decreased radial and circumferential strain over the course of 1 week. Magn Reson Med, 2009. © 2008 Wiley‐Liss, Inc.  相似文献   
999.
Monoclonal antibody (MAb) A33 was labeled with the positron emitter 76Br (T(1/2) = 16.2 h). Direct labeling was done using the conventional chloramine-T method. After optimization of the labeling conditions, a maximum yield (mean +/- max error) of 77 +/- 2% was obtained at pH 6.8. In vitro binding of 76Br-A33 to SW1222 colonic cancer cells showed that the immunoreactivity was retained. Also, the MAbs 38S1 and 3S193 and the peptide hEGF were 76Br-labeled, resulting in labeling yields (mean +/- max error) of 75 +/- 3%, 63 +/- 4%, and 73 +/- 0.1%, respectively. We conclude that antibodies and peptides can be labeled conveniently with 76Br for the purpose of whole-body tumour imaging by positron emission tomography.  相似文献   
1000.

Introduction

Mammographic density is known to be a strong risk factor for breast cancer. A particularly strong association with risk has been observed when density is measured using interactive threshold software. This, however, is a labour-intensive process for large-scale studies.

Methods

Our aim was to determine the performance of visually assessed percent breast density as an indicator of breast cancer risk. We compared the effect on risk of density as measured with the mediolateral oblique view only versus that estimated as the average density from the mediolateral oblique view and the craniocaudal view. Density was assessed using a visual analogue scale in 10,048 screening mammograms, including 311 breast cancer cases diagnosed at that screening episode or within the following 6 years.

Results

Where only the mediolateral oblique view was available, there was a modest effect of breast density on risk with an odds ratio for the 76% to 100% density relative to 0% to 25% of 1.51 (95% confidence interval 0.71 to 3.18). When two views were available, there was a considerably stronger association, with the corresponding odds ratio being 6.77 (95% confidence interval 2.75 to 16.67).

Conclusion

This indicates that a substantial amount of information on risk from percentage breast density is contained in the second view. It also suggests that visually assessed breast density has predictive potential for breast cancer risk comparable to that of density measured using the interactive threshold software when two views are available. This observation needs to be confirmed by studies applying the different measurement methods to the same individuals.  相似文献   
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