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151.
A laser fluorescence (LF) device is a portable tool, but it does not measure minor mineral changes. Our in vitro study aim is to propose the association of an LF with two fluorescent dyes and to evaluate the performance in detecting and quantifying early demineralization. Artificial caries lesions are created in 40 primary canine teeth using a demineralizing solution (pH=4.8) for 12, 24, 48, and 96 h. LF measurements are performed with DIAGNOdent after demineralization in these samples and in 20 sound primary teeth. Measurements with LF with 0.2-mM tetrakis(N-methylpyridyl)porphyrin (LF TMPyP) and with 4-mM protoporphyrin IX (LF PPIX) are made. The amount of calcium loss is determined by atomic emission spectrometry. A correlation between LF and LF with dyes and mineral loss and receiver operating characteristics analysis are performed, as well as comparisons of sensitivity, specificity, and accuracy values. Significant correlation is obtained with LF TMPyP and mineral loss of lesions demineralized for 24, 48, and 96 h. Better performance is achieved with LF TMPyP for all parameters than with LF alone. LF PPIX does not present good results. In conclusion, LF TMPyP provides good performance in detecting and quantifying very early enamel caries lesions. 相似文献
152.
To describe the epidemiology of serious winter sports-related injuries resulting in hospitalization in children and adolescents, we prospectively collected and analyzed records of all winter sports-related injuries requiring hospitalization at our respective institutions from 1996 to 2000. We identified 101 patients with a mean age of 10.7 years, of whom 68% were male and 32% female. Skiers accounted for 71% and snowboarders 26% of injuries; 3% of injuries were snowmobile-or luge-related. Leading mechanisms of injury were ground level falls (50%), crashes into trees, (18%), and falls from ski lift (13%). Approximately 26% of the patients met criteria for trauma-team activation. Leading diagnoses were head injury (20%), femur fracture (18%), and concussion (11%). Five patients required admission to the intensive care unit. The median injury severity score (ISS) was 7; 8% of patients had an ISS score > 15. Abbreviated Injury Scale-1990 scores of > or = 3 were noted in 34% of the patients. We conclude that Injuries sustained through participation in winter sports may be severe, especially in the case of injuries involving the head. Injury-prevention strategies should focus on head injuries. 相似文献
153.
Haemodynamic response to peripheral venous congestion in patients with unexplained recurrent syncope
Bellard E Fortrat JO Dupuis JM Victor J Lefthériotis G 《Clinical science (London, England : 1979)》2003,105(3):331-337
In patients with recurrent unexplained syncope, exaggerated peripheral venous pooling and impaired circulatory adjustment is thought to contribute to the outcome of a head-up tilt (HUT) test. The present study investigated the role of leg volume changes during venous congestion in the haemodynamic response of patients with recurrent unexplained syncope and the ability to predict the outcome of a HUT test. Changes in calf volume (strain gauge plethysmography), heart rate and arterial blood pressure were recorded in 60 patients with history of unexplained syncope (without postural tachycardia symptom) during venous congestion provoked by pneumatic thigh cuffs while supine at rest and during the initial 10 min of a 45 min 70 degrees HUT test. Twenty-seven patients [age (mean+/-S.D.), 39+/-16 years] exhibited symptoms [HUT(+)] and 33 patients (45+/-14 years) were asymptomatic [HUT(-)]. During venous congestion, mean+/-S.E.M. calf volume increased in both groups [HUT(-), 4.5+/-0.2; HUT(+), 4.8+/-0.4 ml x 100 ml(-1), not significant), but significantly less during head-upright tilt [HUT(-), 3.3+/-0.2, P <0.01; HUT(+), 2.6+/-0.3 ml x 100 ml(-1), P <0.001] without differences between the groups. During venous congestion, arterial pressure increased significantly in asymptomatic HUT(-) patients, but not in the HUT(+) patients. Calf volume changes did not correlate with a symptomatic outcome to a 70 degrees HUT. The lack of exaggerated venous pooling during venous congestion and the inability of calf volume changes to predict a positive HUT suggest that excessive venous pooling does not contribute to the outcome of HUT. Attenuated changes in arterial pressure during venous congestion while supine suggest impaired adjustment of peripheral resistance to leg venous occlusion. 相似文献
154.
Nguyen HP Kobbe P Rahne H Wörpel T Jäger B Stephan M Pabst R Holzmann C Riess O Korr H Kántor O Petrasch-Parwez E Wetzel R Osmand A von Hörsten S 《Human molecular genetics》2006,15(21):3177-3194
Huntington's disease (HD) is caused by an expanded CAG repeatleading to the synthesis of an aberrant protein and to the formationof polyglutamine (polyQ)-containing inclusions and aggregates.Limited information is available concerning the associationof neuropathological markers with the development of behavioralmarkers in HD. Using a previously generated transgenic rat modelof HD (tgHD rat), we performed association studies on the time-courseof behavioral symptoms (motor function, learning, anxiety) andthe appearance of striatal atrophy, 1C2 immunopositive aggregatesand polyQ recruitment sites, a precursor to these aggregates.At the age of 1 month, tgHD rats exhibited reduced anxiety andimproved motor performance, while at 6 months motor impairmentsand at 9 months cognitive decline occurred. In contrast, polyQrecruitment sites appeared at around 69 months of age,indicating that HD-like behavioral markers preceded the appearanceof currently detectable neuropathological markers. Interestingly,numerous punctate sites containing polyQ aggregates were alsoseen in areas receiving afferents from the densely recruitingregions suggesting either transport of recruitment-competentaggregates to terminal projections where initially 1C2 positiveaggregates were formed or different internal properties of neuronsin different regions. Furthermore, striatal atrophy was observedat the age of 12 months. Taken together, our findings supportthe hypothesis of a dynamic process leading to region- and age-specificpolyQ recruitment and aggregation. The dissociation of onsetbetween behavioral and neuropathological markers is suggestiveof as yet undetected processes, which contribute to the earlyphenotype of these HD transgenic rats. 相似文献
155.
BACKGROUND: Psychiatric care for people in Sweden with long-term mental health problems has shifted from institutional to community and home settings. AIM: The aim of this study was to explore and describe mental health nurses' experiences of how structural changes in mental health nursing influence interaction when providing home care to patients with long-term mental health problems. METHOD: We conducted interviews with 11 mental health nurses who provided home care to people with long-term mental health problems. The constant comparative method of grounded theory was used for data collection and analysis. FINDINGS: The process of attempting to reconstruct mental health nursing by entering into the everyday reality of people with long-term mental health problems was identified as the core category. Central to this process was a change in perspective from nurse-controlled to client-centred care. This led to changes in moral values, assessment of client needs, and ways of meeting clients and establishing relationships. However, attempts to reconstruct mental health nursing according to a client-centred perspective became problematic when clients were at risk of harming themselves. In these situations, respondents felt the need to make decisions for clients, and this was experienced as burdensome and lonely. CONCLUSIONS: Our study indicates that the process of reconstructing mental health nursing in line with a client-centred perspective is incomplete. Opportunities to interact with people with mental health problems in the home environment may lead to a broader perspective on the daily lives of these people, but also to a realization that home care cannot be modelled on institutional care. 相似文献
156.
Kovoor P Campbell C Wallace E Byth K Dewsnap B Eipper V Uther J Ross D 《Pacing and clinical electrophysiology : PACE》2003,26(10):1979-1985
Transmural recordings using plunge needle electrodes are useful in mapping ventricular tachyarrhythmia, but they interfere with activation sequences or damage the myocardium. This study evaluated the effects of insertion of 66 transmural needles on myocardial activation, structure, and function. Epicardial maps were performed at thoracotomy using a 40-electrode plaque in five mongrel dogs. Sixty-six transmural plunge needles were introduced into the anterior aspect of the septum and left ventricle. Transmural maps of unipolar electrograms were recorded every 15 minutes via 124 electrodes over a 2-hour period. Epicardial maps were repeated after the needles were removed. All recordings were performed during sinus rhythm and ventricular pacing at 300- and 200-ms cycle lengths. Gated heart pool studies were performed preoperatively and 2 weeks after thoracotomy. Programmed ventricular stimulation was performed 2 weeks after thoracotomy. In total, 15,996 electrograms were analyzed. Maximum negative dV/dt of each electrogram and the activation time at each electrode did not change significantly over the 2 hours of needle insertion. After removal of the needles, epicardial maps were unchanged compared to before needle insertion. Mean left ventricular ejection fraction 2 weeks after needle insertion was 59% versus 58% before needle insertion (P=0.9). No dogs had inducible ventricular tachycardia. Histology showed contraction bands of 0.8-mm diameter adjacent to the needle tracks but no scarring. Insertion of 66 closely spaced plunge needles did not distort epicardial or transmural maps. Multiple needles did not result in myocardial scarring, left ventricular dysfunction, or predispose to ventricular tachycardia. 相似文献
157.
Fernando de Ory José Manuel Echevarría George Kafatos Cleo Anastassopoulou Nick Andrews Josephine Backhouse Guy Berbers Blazena Bruckova Daniel I Cohen Hester de Melker Irja Davidkin Giovanni Gabutti Louise M Hesketh Kari Johansen Sari Jokinen Lindsay Jones Anika Linde Elisabeth Miller Jo?l Mossong Anthony Nardone Maria Cristina Rota Andreas Sauerbrei Fran?ois Schneider Zahava Smetana Annedore Tischer Athanassios Tsakris Robert Vranckx 《Journal of clinical virology》2006,36(2):111-118
BACKGROUND: The aim of the European Sero-Epidemiology Network (ESEN2) is to harmonise the serological surveillance of vaccine-preventable diseases in Europe. OBJECTIVE: To allow comparison of antibody prevalence in different countries by standardising results into common units. STUDY DESIGN: For varicella zoster virus (VZV), a reference laboratory established a panel of 148 samples, characterised by indirect enzyme-immunoassay (ELISA), indirect immunofluorescence, and complement fixation test. Fifty-seven samples were also studied by the fluorescence antibody to membrane antigen test. The geometric mean of the antibody activity (GMAA) obtained from four ELISA determinations was used to characterise each sample of the panel as positive (GMAA: >100 mIU/ml), equivocal (GMAA: 50-100 mIU/ml) or negative (GMAA: <50 mIU/ml) for antibody to VZV (anti-VZV). Thirteen laboratories, using five different ELISA tests, tested the panel. RESULTS: Agreement with the reference laboratory was above 85% in all cases, and the R(2) values obtained from regression analysis of the quantitative results were always higher than 0.87. Finally, the regression equations could be used to convert national values into a common unitage. CONCLUSION: This study confirmed that results for anti-VZV obtained by different ELISA methods can be converted into common units, enabling the comparison of the seroprevalence profiles obtained in the participant countries. 相似文献
158.
Novel role of toll-like receptor 3 in hepatitis C-associated glomerulonephritis 总被引:9,自引:0,他引:9
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Wörnle M Schmid H Banas B Merkle M Henger A Roeder M Blattner S Bock E Kretzler M Gröne HJ Schlöndorff D 《The American journal of pathology》2006,168(2):370-385
Hepatitis C virus (HCV) infection is frequently complicated by glomerulonephritis with immune complexes containing viral RNA. We examined the potential influence of Toll-like receptors (TLRs), specifically TLR3 recognition of viral dsRNA exemplified by polyriboinosinic:polyribocytidylic acid [poly(I:C) RNA]. Normal human kidney stained positive for TLR3 on mesangial cells (MCs), vascular smooth muscle cells, and collecting duct epithelium. Cultured MCs have low TLR3 mRNA levels with predominant intracellular protein localization, which was increased by tumor necrosis factor-alpha, interleukin (IL)-1beta, interferon (IFN)-gamma, and the TLR3 ligand poly(I:C) RNA. Poly(I:C) RNA stimulation of MCs increased mRNA and protein synthesis of IL-6, IL-1beta, M-CSF, IL-8/CXCL8, RANTES/CCL5, MCP-1/CCL2, and ICAM-I; it also increased anti-proliferative and proapoptotic effects, the latter of which was decreased by inhibiting caspase-8. In microdissected glomeruli of normal and non-HCV membranoproliferative glomerulonephritis biopsies, TLR3 mRNA expression was low. In contrast TLR3 mRNA expression was significantly increased in hepatitis C-positive glomerulonephritis and was associated with enhanced mRNA for RANTES/CCL5 and MCP-1/CCL2. We hypothesize that immune complexes containing viral RNA activate mesangial TLR3 during HCV infection, thereby contributing to chemokine/cytokine release and effecting proliferation and apoptosis. Thus, TLR3 expression on renal cells, and especially MCs, may establish a link between viral infections and glomerular diseases. 相似文献
159.
Arne Ekeland Tor Kjetil Nerhus Sigbjørn Dimmen Elisabeth Thornes Stig Heir 《The Knee》2017,24(2):380-389
Background
To report time dependent functional improvement and predictive risk factors for failure when the load in varus knees with medial osteoarthritis is shifted from the medial to the lateral knee compartment.Methods
Forty-nine consecutive patients (52 knees), mean age 47 (31–64) years, underwent a high tibial opening-wedge valgus osteotomy stabilized with a Puddu plate and bone grafting. The patients were evaluated with the Knee Injury and Osteoarthritis Outcome Score (KOOS) preoperatively and at three and six months, one, two, five and 10 years postoperatively with a mean follow-up time of 8.3 years (2.0–10.6).Results
Mean angular correction was 8.0° (four to 12). The five subscores of KOOS increased significantly during the first year by 40–131% from preoperative values, the good results remaining throughout the 10-year follow-up for those with a surviving osteotomy. The outcome was related to the grade of preoperative osteoarthritis. Seven knees were converted to total knee arthroplasty (TKA) mean 6.2 years (two to nine) post-operatively, and had a lower KOOS preoperatively than those of surviving osteotomies. The osteotomy survival rate at five years was 94% and at 10 years 83%. Patients with KOOS subscore quality of life (QoL) < 44 at the two-year follow-up had a 11.7 times higher risk for later TKA than those with QoL ≥ 44 (P = 0.017).Conclusion
High tibial opening-wedge osteotomy for medial knee osteoarthritis resulted in good functional recovery after one year and favorable mid-term results. It may be a good treatment option for middle-aged patients with varus knees and medial osteoarthritis in order to prevent or postpone TKA. 相似文献160.