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An insertion/deletion polymorphism in the angiotensin-convertingenzyme (ACE) gene accounts for approximately 50% of the variancein plasma ACE concentration: deletion homozygotes (DD) havethe highest, and insertion homozygotes (II) the lowest ACE concentrations.ACE is responsible for the generation of angiotensin II, whichis implicated in the development of left ventricular hypertrophy,an independent risk factor for morbidity and mortality in hypertension.The aim of this study was to investigate the contribution ofACE genotype to the development of left ventricular hypertrophyin patients with essential hypertension. Eighty-five patientswith essential hypertension underwent echocardiographic assessmentof left ventricular mass index (LVMI) and determination of ACEgenotype from leukocyte DNA by polymerase chain reaction. Therewas no significant difference in LVMI among the genotypes (II,ID, DD). Analysis of covariance modelled for LVMI showed a significantinteraction with systolic blood pressure (p = 0.036). but notdiastolic blood pressure (p = 0.453). The relationship betweenLVMI and systolic blood pressure was strongest in the deletionhomozygotes (p = 0.002, R2 = 0.47), and also present in theheterozygotes (p = 0.013, R2 = 0.40). No relationship was seenin the insertion homozygotes (p = 0.914, R2 = 0.23) These findingssuggest that the effect of blood pressure on LVMI in essentialhypertension is expressed only in the presence of the ACE genedeletion allele.  相似文献   
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Sjögren''s syndrome (SS) is characterized by a focal periductal salivary gland infiltrate consisting mainly of T and B lymphocytes. Most of the T cells bear the memory of CD4+ Th-1-like phenotype and express high levels of class II, though CD8+ cells are also present. We have studied 17 labial salivary gland and 15 peripheral blood T cell clones from a patient with primary SS. The tissue clones were 71% CD8+ and 29% CD4+, and the peripheral blood-derived clones were 60% CD8+ and 40% CD4+. The CD4+ T cell clones from both the salivary gland and autologous peripheral blood were of the Th1 phenotype, in that they produced interferon-gamma (IFN-γ) and IL-2 but very little IL-4 after 24 h stimulation with phorbol myristate acetate and anti-CD3 antibody. The salivary gland-derived CD4+ clones produced 15 times more IL-10 (7·92 ng/ml) than peripheral blood-derived CD4+ clones (0·52 ng/ml, P≤0·02). The tissue CD8+ clones produced 1·2 times (P<0·04) more IFN-γ and CD4+ clones produced 3·5 times less IL-2 (P<0·02) than the respective PBM-derived clones. The accumulation of Th1-type cells producing high levels of IL-10 in the salivary gland suggests a specific immunoregulatory function at the site of inflammation in SS.  相似文献   
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The Nominal Group Technique: A Research Tool for General Practice?   总被引:3,自引:0,他引:3  
Qualitative methods are increasingly recognized as valuable,yet practitioners face difficult decisions in their choice ofmethod and the process of analysis. The nominal group techniquecombines quantitative and qualitative data collection in a groupsetting, and avoids problems of group dynamics associated withother group methods such as brainstorming, Delphi and focusgroups. Idea generation and problem solving are combined ina structured group process, which encourages and enhances theparticipation of group members. The stages involved in conductinga nominal group are described, and practical problems of itsuse in a health care setting are discussed with reference toa study of the priorities of care of diabetic patients, carersand health professionals. Some potential applications of thetechnique in audit and exploratory research are also outlined.  相似文献   
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  • ? A pilot study of catheterized women was designed to investigate their perceptions of pain and discomfort during the procedure.
  • ? The study aimed to test the feasibility of conducting a larger randomized controlled trial.
  • ? Problems were encountered during the execution of the study, due to the need to conform to established principles in clinical research.
  • ? Restrictions on access to patients impinged upon the opportunity to ‘cast the net wide’ in order to generate meaningful data.
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Short-term exposure to high concentrations of ozone has beenshown to increase airway responsiveness in normal humans andin all laboratory animal species studied to date. While ourknowledge concerning the pulmonary effects of single exposuresto ozone has increased rapidly over recent years, the effectsof repeated exposures are less understood. The goal of the presentstudy was to determine whether airway responsiveness is increasedafter near-lifetime exposure to ozone. Airway segments representingapproximately eighth generation airways were isolated from Fischer344 rats of both genders that had been exposed for 6 hr perday, 5 days per week for 20 months to 0, 0.12, 0.5, or 1.0 partsper million (ppm) ozone. Circtimferential tension developmentwas measured in isolated airways in response to bethanechol,acetylcholine, and electrical field stimulation. Responsivenessof the airways to the contractile stimuli was described by theeffective dose or frequency that elicited half-maximum contraction(ED50) and the maximum response. Since ozone exposure is associatedwith remodeling of peripheral airways, smooth muscle area wasdetermined and tension responses were normalized to the areameasurements. Before normalization of tension data to smoothmuscle area, neither the ED50 nor maximum response of smallbronchi to the contractile stimuli was altered after chronicozone exposure. Smooth muscle area was greater in airways isolatedfrom animals that had been exposed to 0.5 ppm ozone. After accountingfor smooth muscle area, maximum responses of the small bronchiisolated from male rats were significantly reduced after 0.12and 0.5 ppm ozone. Although not significant statistically, asimilar trend was observed in airways isolated from female rats.These results suggest that the increase in airway responsivenessassociated with acute ozone exposure does not persist duringnear-lifetime exposure. Although the mechanism responsible forthe adaptation to the effects of 03 on airway responsivenessis unknown, the results indicate that smooth muscle cell functionwas compromised by the chronic exposure. The mechanism(s) responsiblefor mediating this effect and the relevance of these resultsto humans remains to be determined.  相似文献   
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The aim of our study was to compare the safety and efficacyof a new preparation, Dysprosium-165 Hydroxide Macro-aggregate(165Dy) with Yttrium-90 Silicate (90Y) for radiation synovectomyof the knee in patients with RA and OA. A multicentre doubleblind clinical trial with subjects randomized to receive 165Dyor 90Y was undertaken in Sydney, Melbourne and Perth. Seventyknees of 59 patients were studied, using as clinical end pointmeasurements pain in the knee on walking, pain in the knee atrest and stiffness in the knee after rest. Cytogenetic damage,knee retention and extra-articular spread of the radionuclideto regional lymph nodes, liver, urine and blood were evaluated.There was no significant difference in clinical response inthe two treatment groups for either RA or OA. Chromosomal changesoccurred with equal frequency and the knee retention and extra-articularleakage of radiocolloids to regional lymph nodes and liver werecomparable in the two groups. For radiation synovectomy of theknee, 165Dy is at least as safe and as effective as 90Y andhas the advantage of a short half-life (2.334 h) and hence requiresa shorter period of post-injection immobilization and hospitalization. KEY WORDS: Radiation synovectomy, Dysprosium-165, Yttrium-90, Rheumatoid synovitis, Osteoarthritis  相似文献   
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