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891.
Fox E Harkins D Taylor H McMullan M Han H Samdarshi T Garrison R Skelton T 《American heart journal》2004,148(6):979-984
Background
Despite the potential link between mitral annular calcification (MAC) and atherosclerosis, there is limited data regarding the prevalence of MAC in African Americans and its relationship with coronary heart disease (CHD)events in this high-risk population.Methods
The study population included 2409 African American participants of the Artherosclerotic Risk in Communities study (ARIC) undergoing echo examinations between 1993-1996. The primary outcome was incident CHD events [defined as fatal coronary event, hospitalized myocardial infarction or cardiac procedure]. MAC was considered a binary variable (yes/no). The Cox proportional hazard model was used for the analysis and the model was adjusted for gender, age, body mass index, hypertension, diabetes, smoking status, renal function (based on serum creatinine), high LDL and low HDL.Results
Of the 2409 in the study population, 1549 (64%) were women and the mean age was 59.2 ± 5.8 years (range 49-75). MAC was positively associated with age and renal function. The overall prevalence of MAC was 4.6% for women and 5.6% for men. In participants aged ≥ 70, the prevalence of MAC was 10% in women and 15.2% in men. During a median follow-up of 4.8 years, there were 237 total incident CHD events recorded. After adjustment, the hazard ratio for CHD events among the MAC subgroup was 2.32 (95% CI, 1.11-4.87).Conclusions
In this relatively young population of middle-aged African Americans, the prevalence of MAC is low; however, the presence of MAC incurs a significant risk for coronary events. 相似文献892.
Grace H. Elta MD Karim A. Fawaz MD Yogeshwar Dayal MD Alison M. McLean MD Ervin Philipps MD Stephen M. Bloom MD Robert E. Paul MD Marshall M. Kaplan MD 《Digestive diseases and sciences》1983,28(1):7-12
We have reviewed the clinical manifestations, endoscopic findings, pathology, and upper gastrointestinal x-rays in 10 patients with chronic erosive gastritis, a disorder that was rarely recognized before the use of double-contrast upper gastrointestinal radiology and endoscopy. The characteristic x-ray appearance is that of a series of 3 to 11-mm nodules, some with central collections of barium, that are distributed along rugal folds and usually extend into the antrum. The endoscopic appearance is similar: small erythematous nodules with shallow central erosions. The pathology differs from that seen in peptic ulcer disease. There are few polymorphonuclear leukocytes and a predominance of plasma cells in the inflammatory infiltrate. Seven of our patients presented with epigastric pain similar to that of peptic ulcer disease; four of these also had anorexia and weight loss. In two other patients anorexia and weight loss were the only symptoms. One patient was asymptomatic. All nine symptomatic patients responded to antacid treatment. However, repeat x-rays demonstrated persistence of the nodules, although the central erosions usually disappeared. The etiology is unknown. Chronic erosive gastritis appears to be a distinct entity different from peptic ulcer disease. 相似文献
893.
894.
Victor Teplov Ervin Nippolainen Alexander A. Makarenko Rashid Giniatullin Alexei A. Kamshilin 《Biomedical optics express》2014,5(9):3123-3139
Blood pulsation imaging (BPI) is a non-invasive optical method based on photoplethysmography (PPG). It is used for the visualization of changes in the spatial distribution of blood in the microvascular bed. BPI specifically allows measurements of the relative phase of blood pulsations and using it we detected a novel type of PPG fast waveforms, which were observable in limited areas with asynchronous regional blood supply. In all subjects studied, these fast waveforms coexisted with traditional slow waveforms of PPG. We are therefore presenting a novel lock-in image processing technique of blood pulsation imaging, which can be used for detailed temporal characterization of peripheral microcirculation.OCIS codes: (170.3880) Medical and biological imaging, (280.1415) Biological sensing and sensors 相似文献
895.
M G Ervin R D Leake M G Ross G C Calvario D A Fisher 《The Journal of clinical investigation》1985,75(5):1696-1701
Arginine vasotocin ([8-arginine]-oxytocin) (AVT), the primary antidiuretic principle in submammalian vertebrates, has been reported to be present in mammalian pituitary and pineal glands. Although the most phyletically ubiquitous of the known neurohypophysial peptides, AVT is still not recognized as a mammalian hormone. We examined plasma, urine, and amniotic fluid from fetal lambs by radioimmunoassay (RIA) for evidence of AVT to assess the possibility of its being such a hormone. Measureable quantities of AVT-like immunoreactivity (irAVT) were observed in fetal plasma (2.4 +/- 0.2 pg/ml), urine (1.4 +/- 0.2 pg/ml), and amniotic fluid (1.9 +/- 0.2 pg/ml). Since the AVT antiserum shows minimal cross-reactivity with arginine vasopressin (AVP) and oxytocin (OT), measurements of AVP and OT concentrations in the same biological fluids also were conducted with specific antisera. The results suggest that the irAVT was not accountable on the basis of cross-reaction. To further verify the identity of the irAVT, a high pressure liquid chromatography system using RIA as a means of detection was developed. This system is sufficiently sensitive to allow the separation and quantitation of picogram quantities of the synthetic peptides AVT, AVP, and OT. In this system, the irAVT in fetal plasma, urine, and amniotic fluid appeared as a single peak coeluting with synthetic AVT. These results indicate that AVT is present in ovine fetal plasma and support the view that the fetus secretes this peptide. The physiological significance of circulating AVT remains to be defined. 相似文献
896.
BACKGROUND: Previous studies have shown that high molecular-weight non-dialysable material derived from cranberry juice (NDM) inhibits co-aggregation of a variety of oral bacteria. OBJECTIVES: In the present study, we examined the effect of NDM on several constituents of the dental biofilm, glucosyltransferase (GTF) and fructosyltransferase (FTF), as well as on the adhesion of Streptococcus sobrinus. RESULTS: The activity of immobilized and soluble GTF and FTF was inhibited by NDM (P > 0.05). NDM also inhibited adhesion of S. sobrinus to hydroxyapatite (P < 0.05). CONCLUSIONS: Our results indicate that NDM may affect biofilm formation. One of the proposed mechanisms is via inhibition of extracellular polysaccharide synthesis, which promote the sucrose-dependent adhesion of oral bacteria as S. sobrinus. 相似文献
897.
Ervin NE 《Clinical nurse specialist CNS》2005,19(6):296-301
PURPOSE: The purpose of this article is to describe how clinical nurse specialists can promote the development of knowledge and skills in nurses as one step toward making evidence-based nursing practice the norm in all patient care settings. BACKGROUND: The need for the use of evidence in nursing practice has been highlighted for several decades. Moving evidence more quickly into practice requires that nursing use many strategies. DESCRIPTION OF STRATEGY: The strategy of clinical coaching is proposed in this article for the development of skills in nurses specifically to promote evidence-based nursing practice. Clinical coaching is a relationship for the purpose of building skills. This strategy is aimed at increasing foundational staff nurse knowledge and skills. CONCLUSION: The achievement and maintenance of evidence-based nursing practice take continuous attention from clinical nurse specialists. Clinical coaching is only one part of a comprehensive approach for establishing and sustaining evidence-based nursing practice. 相似文献
898.
G E Laramore C B Scott M al-Sarraf R E Haselow T J Ervin R Wheeler J R Jacobs D E Schuller R A Gahbauer J G Schwade 《International journal of radiation oncology, biology, physics》1992,23(4):705-713
To test the efficacy of sequential chemotherapy as an adjuvant to surgery and postoperative radiotherapy for patients with locally-advanced but operable squamous cell cancers of the head and neck region, a randomized clinical trial was conducted under the auspices of the Head and Neck Intergroup (Radiation Therapy Oncology Group, Southwest Oncology Group, Eastern Oncology Group, Cancer and Leukemia Group B, Northern California Oncology Group, and Southeast Group). Eligible patients had completely resected tumors of the oral cavity, oropharynx, hypopharynx, or larynx. They were then randomized to receive either three cycles of cis-platinum and 5-FU chemotherapy followed by postoperative radiotherapy (CT/RT) or postoperative radiotherapy alone (RT). Patients were categorized as having either "low-risk" or "high-risk" treatment volumes depending on whether the surgical margin was greater than or equal to 5 mm, there was extracapsular nodal extension, and/or there was carcinoma-in-situ at the surgical margins. Radiation doses of 50-54 Gy were given to "low-risk" volumes and 60 Gy were given to "high-risk" volumes. A total of 442 analyzable patients were entered into this study with the mean-time-at-risk being 45.7 months at the time of the present analysis. The 4-year actuarial survival rate was 44% on the RT arm and 48% on the CT/RT arm (p = n.s.). Disease-free survival at 4 years was 38% on the RT arm compared to 46% on the CT/RT arm (p = n.s.). At 4 years the local/regional failure rate was 29% vs. 26% for the RT and CT/RT arms, respectively (p = n.s.). The incidence of first failure in the neck nodes was 10% on the RT arm compared to 5% on the CT/RT arm (p = 0.03 without adjusting for multiple testing) and the overall incidence of distant metastases was 23% on the RT arm compared to 15% on the CT/RT arm (p = 0.03). Treatment related toxicity is discussed in detail, but, in general, the chemotherapy was satisfactorily tolerated and did not affect the ability to deliver the subsequent radiotherapy. Implications for future clinical trials are discussed. 相似文献
899.
Stereotactic radiosurgery is often used for treating functional disorders. For some of these disorders, the size of the target can be on the order of a millimeter and the radiation dose required for treatment on the order of 80 Gy. The very small radiation field and high prescribed dose present a difficult challenge in beam calibration, dose distribution calculation, and dose delivery. In this work the dose distribution for dynamic stereotactic radiosurgery, carried out with 1.5 and 3 mm circular fields, was studied. A 10 MV beam from a Clinac-18 linac (Varian, Palo Alto, CA) was used as the radiation source. The BEAM/EGS4 Monte Carlo code was used to model the treatment head of the machine along with the small-field collimators. The models were validated with the EGSnrc code, first through a calculation of percent depth doses (PDD) and dose profiles in a water phantom for the two small stationary circular beams and then through a comparison of the calculated with measured PDD and profile data. The three-dimensional (3-D) dose distributions for the dynamic rotation with the two small radiosurgical fields were calculated in a spherical water phantom using a modified version of the fast XVMC Monte Carlo code and the validated models of the machine. The dose distributions in a horizontal plane at the isocenter of the linac were measured with low-speed radiographic film. The maximum sizes of the Monte Carlo-calculated 50% isodose surfaces in this horizontal plane were 2.3 mm for the 1.5 mm diameter beam and 3.8 mm for the 3 mm diameter beam. The maximum discrepancies between the 50% isodose surface on the film and the 50% Monte Carlo-calculated isodose surfaces were 0.3 mm for both the 1.5 and 3 mm beams. In addition, the displacement of the delivered dose distributions with respect to the laser-defined isocenter of the machine was studied. The results showed that dynamic radiosurgery with very small beams has a potential for clinical use. 相似文献
900.
ABSTRACT: BACKGROUND: Kosovo is the newest state in Europe facing a particularly difficult socioeconomic and political transition. The available evidence on socioeconomic conditions and quality of life of elderly people in Kosovo is scarce notwithstanding the ageing trend due to lowering of fertility rates and a higher life-expectancy. In this context, the aim of our study was to assess the socioeconomic conditions of elderly people in post-war Kosovo. METHODS: A cross-sectional study was conducted in Kosovo in January-March 2011 including an age- sex-and residence (urban vs. rural)-stratified sample of 1,890 individuals (83.5% response) aged 65 years and over. A structured questionnaire included assessment of socio-demographic and socioeconomic characteristics including educational level and self-perceived poverty. Binary logistic regression was used to assess the association of self-perceived poverty with socio-demographic and socioeconomic factors. RESULTS: The educational level in this representative sample of elderly people in Kosovo was quite low, particularly among women. About 47% of respondents perceived themselves as poor, or extremely poor (41% of men and 52% of women). In multivariable-adjusted models, self-perceived poverty was higher among older women, low educated individuals, urban residents, and elderly individuals living alone. CONCLUSIONS: Findings from this study indicate that the socioeconomic situation of the elderly population in Kosovo is rather challenging. Demographic trends coupled with the economic and political transition raise serious concerns about increasing needs for socioeconomic support of elderly people in Kosovo. Specific policies and actions should be considered by a number of stakeholders, including government and civil society in transitional Kosovo. 相似文献