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排序方式: 共有3604条查询结果,搜索用时 15 毫秒
71.
Baelum V Hintze H Wenzel A Danielsen B Nyvad B 《Community dentistry and oral epidemiology》2012,40(3):257-266
Baelum V, Hintze H, Wenzel A, Danielsen B, Nyvad B. Implications of caries diagnostic strategies for clinical management decisions. Community Dent Oral Epidemiol 2011. © 2011 John Wiley & Sons A/S Abstract – Objectives: In clinical practice, a visual–tactile caries examination is frequently supplemented by bitewing radiography. This study evaluated strategies for combining visual–tactile and radiographic caries detection methods and determined their implications for clinical management decisions in a low‐caries population. Methods: Each of four examiners independently examined preselected contacting interproximal surfaces in 53 dental students aged 20–37 years using a visual–tactile examination and bitewing radiography. The visual–tactile examination distinguished between noncavitated and cavitated lesions while the radiographic examination determined lesion depth. Direct inspection of the surfaces following tooth separation for the presence of cavitated or noncavitated lesions was the validation method. The true‐positive rate (i.e. the sensitivity) and the false‐positive rate (i.e. 1‐specificity) were calculated for each diagnostic strategy. Results: Visual–tactile examination provided a true‐positive rate of 34.2% and a false‐positive rate of 1.5% for the detection of a cavity. The combination of a visual–tactile and a radiographic examination using the lesion in dentin threshold for assuming cavitation had a true‐positive rate of 76.3% and a false‐positive rate of 8.2%. When diagnostic observations were translated into clinical management decisions using the rule that a noncavitated lesion should be treated nonoperatively and a cavitated lesion operatively, our results showed that the visual–tactile method alone was the superior strategy, resulting in most correct clinical management decisions and most correct decisions regarding the choice of treatment. 相似文献
72.
Yi Su Wendelin Bhm Marco Wenzel Silvia Paasch Margret Acker Thomas Doert Eike Brunner Thomas Henle Jan J. Weigand 《RSC advances》2020,10(73):45116
The increasing concerns on uranium and rare earth metal ion pollution in the environment require sustainable strategies to remove them from wastewater. The present study reports an eco-friendly approach to convert a kind of protein-rich biomass, brewer''s spent grain (BSG), into effective biosorbents for uranyl and rare earth metal ions. The employed method reduces the energy consumption by performing the hydrothermal treatment at a significantly lower temperature (150 °C) than conventional hydrothermal carbonization. In addition, with the aid of the Maillard reaction between carbohydrates and proteins forming melanoidins, further activation processes are not required. Treatment at 150 °C for 16 h results in an altered biosorbent (ABSG) with increased content of carboxyl groups (1.46 mmol g−1) and a maximum adsorption capacity for La3+, Eu3+, Yb3+ (pH = 5.7) and UO22+ (pH = 4.7) of 38, 68, 46 and 221 mg g−1, respectively. Various characterization methods such as FT-IR, 13C CP/MAS NMR, SEM-EDX and STA-GC-MS analysis were performed to characterize the obtained material and to disclose the adsorption mechanisms. Aside from oxygen-containing functional groups, nitrogen-containing functional groups also contribute to the adsorption. These results strongly indicate that mild hydrothermal treatment of BSG could be applied as a greener, low-cost method to produce effective adsorbents for uranyl and rare earth metal ion removal.Effective biosorbent ABSG is obtained via hydrothermal treatment of BSG at low temperature without activation, minimizing energy consumption and environmental impact. 相似文献
73.
Balzar S Strand M Rhodes D Wenzel SE 《The Journal of allergy and clinical immunology》2007,119(4):855-862
BACKGROUND: IgE-mediated responses contribute to allergy and asthma. Little is understood regarding the relationship of tissue IgE to systemic IgE, inflammation or clinical outcomes. OBJECTIVES: To evaluate local IgE expression and cellular inflammation in the proximal and distal lung of normal subjects and subjects with asthma of varying severity and relate those tissue parameters to systemic IgE levels, atopy, lung function, and history of severe exacerbations of asthma. METHODS: Tissue from more than 90 subjects with eosinophilic (SAeo(+)) and noneosinophilic (SAeo(-)) severe asthma, mild asthma and normal subjects were immunostained for IgE, signal-amplifying isoform of IgE receptor (FcepsilonRIbeta) and markers of mast cells, eosinophils, and lymphocytes. Tissue expression of IgE, FcepsilonRIbeta, cellular inflammation, serum IgE, and atopy were compared. Regression models were used to determine the relationship of local and systemic IgE to lung function and severe exacerbations of asthma. RESULTS: Mast cell-bound IgE was present along airways but absent in lung parenchyma. Although the groups were similar in systemic/serum IgE and atopy, local/tissue IgE was highest in SAeo(+) and correlated with eosinophils and lymphocytes (r(s) = 0.52, P < .0001; and r(s) = 0.23, P = .03, respectively). Higher local IgE was associated with better lung function, but also with more severe exacerbations of asthma. CONCLUSION: Local IgE appears to be primarily a component of responses within the mucosal immune compartment and is related to cellular inflammation, lung function, and clinical outcomes in asthma. CLINICAL IMPLICATIONS: Local/airway IgE-related processes rather than systemic markers of atopy may be relevant in determining clinical outcomes in asthma. 相似文献
74.
Hardy Weisshoff Katrin Wenzel Sarah Schulze-Rothe Heike Nikolenko Hanna Davideit Niels-Peter Becker Peter Göttel G. Susan Srivatsa Margitta Dathe Johannes Müller Annekathrin Haberland 《Journal of pharmaceutical sciences》2018,107(8):2033-2041
Possible unwanted folding of biopharmaceuticals during manufacturing and storage has resulted in analysis schemes compared to small molecules that include bioanalytical characterization besides chemical characterization. Whether bioanalytical characterization is required for nucleotide-based drugs, may be decided on a case-by-case basis. Nucleotide-based pharmaceuticals, if chemically synthesized, occupy an intermediate position between small-molecule drugs and biologics. Here, we tested whether a physicochemical characterization of a nucleotide-based drug substance, BC 007, was adequate, using circular dichroism (CD) spectroscopy. Nuclear magnetic resonance confirmed CD data in one experimental setup. BC 007 forms a quadruplex structure under specific external conditions, which was characterized for its stability and structural appearance also after denaturation using CD and nuclear magnetic resonance. The amount of the free energy (ΔG0) involved in quadruplex formation of BC 007 was estimated at +8.7 kJ/mol when dissolved in water and +1.4 kJ/mol in 154 mM NaCl, indicating structural instability under these conditions. However, dissolution of the substance in 5 mM of KCl reduced the ΔG0 to ?5.6 kJ/mol due to the stabilizing effect of cations. These results show that positive ΔG0 of quadruplex structure formation in water and aqueous NaCl prevents BC 007 from preforming stable 3-dimensional structures, which could potentially affect drug function. 相似文献
75.
Neurauter A Kramer-Johansen J Eilevstjønn J Myklebust H Wenzel V Lindner KH Eftestøl T Steen PA Strohmenger HU 《Resuscitation》2007,73(2):246-252
The duration of untreated ventricular fibrillation (VF) is of paramount importance for CPR success. Moreover, therapeutic interventions taking into account the interval between cardiac arrest onset and initiation of CPR improve outcome. This study was performed to investigate whether VF feature analysis could be used to estimate the duration of VF in patients with out-of-hospital cardiac arrest. Demographic data recorded according to the Utstein guidelines and ECG recordings of 376 cardiac arrest patients from three European areas were analysed. Ten features in the time and frequency domain derived from different sub-bands of the initial VF ECG (n=127) were evaluated. The correlation between VF ECG features and cardiac arrest times was investigated using Pearson's correlation coefficient in a subset of 40 patients with reliably estimated downtimes and artefact-free initial VF tracings. No significant correlation (p<.05) between any of the VF ECG features and downtime could be found. The duration of cardiac arrest could not be estimated reliably from human VF ECG single feature analysis. 相似文献
76.
Rossmann H Büchler E Wenzel JJ Neukirch C du Prel JB Lackner KJ 《Clinical chemistry》2007,53(5):980-982
BACKGROUND: Allele frequencies of single-nucleotide polymorphisms (SNPs) can be quantified from DNA pools. The conventional preparation of DNA pools requires DNA isolation and quantification for each blood sample. We hypothesized that pooling of whole blood samples according to their leukocyte count, which determines DNA content, would be as reliable as the conventional pooling method but much less tedious to perform. METHODS: We collected 100 whole blood samples and measured the leukocyte count. Samples were frozen until further use. After thawing, pools were generated by combining aliquots containing an equal number of leukocytes. In parallel, DNA was extracted from another aliquot, DNA concentration was measured, and DNA concentration-based pools were assembled. All original samples were genotyped directly using 4 different SNP assays to obtain the exact allele frequencies in the pool. In addition, samples of known genotypes were mixed according to the DNA concentration or the leukocyte count to generate artificial samples of known allele frequencies. We analyzed pools and mixes in triplicate by pyrosequencing and calculated allelic frequencies. RESULTS: Leukocyte and DNA pooling provided equally accurate and precise SNP frequencies comparable to published data. CONCLUSION: DNA and leukocyte pooling are both suitable strategies to determine allele frequencies in frozen samples. The leukocyte pooling approach is much less tedious, quicker, and less expensive. It should be always considered if leukocyte counts are available. 相似文献
77.
Chan KS Wenzel S Orlando M Montagnet C Mandell W Becker K Ebener P 《The American journal of drug and alcohol abuse》2004,30(4):871-891
Prior research has demonstrated that therapeutic communities (TCs) are effective at improving posttreatment outcomes for substance abusers. However, little is known about the in-treatment experience for clients with different backgrounds, experiences, and needs. The aim of this study is to examine the in-treatment experience for different clients by exploring the relationships between treatment process and client characteristics. A comprehensive measure of treatment process, operationalized as Community Environment and Personal Change and Development and change was administered to 447 adults and 148 adolescents receiving treatment at community-based TC programs in New York, California, and Texas. Data on demographic characteristics, substance use and treatment history, and client risk factors were extracted from intake interviews and analyzed separately for adolescent and adult residents. Multivariate general linear models were used to examine the effect of client variables on treatment process, after controlling for treatment duration and program effects. Within adult programs, clients who were 25 years or older, female, and had a prior drug treatment experience had higher Community Environment scores. Adolescents with one or more arrests within the past 2 years had lower scores on both process dimensions of Community Environment and Personal Development and Change. Our results indicate the need to understand why adult clients who are younger, male, and have no prior treatment history and adolescent clients with recent arrests reported lower ratings of treatment process. Future research should also examine the role of modifiable mediators so that appropriate strategies to enhance therapeutic engagement may be developed as necessary. 相似文献
78.
Gonçalves CC Reiche EM De Abreu Filho BA Silveira TG Felizardo TC Maia KR Costacurta R Padovesi EJ Dias Filho BP Jankevicius SI Jankevicius JV 《The American journal of tropical medicine and hygiene》2002,66(1):91-102
A Western blot method that uses antigens from culture promastigote forms of Leishmania (Viannia) braziliensis, L. (Leishmania) amazonensis, L. (Leishmania) tropica, and a trypanosomatid (strain 268T) isolated from naturally infected tomatoes was evaluated for laboratory diagnosis of American tegumentary leishmaniasis (ATL). Serum samples were obtained from 108 patients with ATL (group I), 23 chagasic patients (group II), 32 patients with other diseases (group III), and 78 healthy individuals (group IV). The overall analysis showed a sensitivity of 76.90%, 90.40%, 78.50%, and 87.90%, a specificity of 100%, 93.80%, 87.80%, and 77.10%, a positive predictive value of 100%, 94.00%, 89.50%, and 72.50%, a negative predictive value of 75.70%, 90.00%, 75.40%, and 90.20%, and a concordance coefficient kappa of 0.7358, 0.8400, 0.6491, and 0.6287 for L. (V.) braziliensis, L. (L.) amazonensis, L. (L.) tropica, and strain 268T antigens, respectively. The antigenic profile recognized by serum samples from patients with ATL and with Chagas' disease permits serologic distinction between these infections. 相似文献
79.
Alterations of the arginine metabolome in asthma 总被引:1,自引:0,他引:1
Lara A Khatri SB Wang Z Comhair SA Xu W Dweik RA Bodine M Levison BS Hammel J Bleecker E Busse W Calhoun WJ Castro M Chung KF Curran-Everett D Gaston B Israel E Jarjour N Moore W Peters SP Teague WG Wenzel S Hazen SL Erzurum SC;National Heart Lung Blood Institute's Severe Asthma Research Program 《American journal of respiratory and critical care medicine》2008,178(7):673-681
80.
Suzanne L. Wenzel Joan S. Tucker Marc N. Elliott Katrin Hambarsoomians 《AIDS and behavior》2007,11(2):9-20
HIV/AIDS increasingly affects women, and housing status is important to understanding HIV risk behaviors among women. The goal of this study is to enhance understanding of the association between housing status and a key sexual risk behavior, having multiple sex partners, by investigating the extent to which housing status differences can be accounted for by hypothesized explanatory factors. In a probability sample of 833 women in Los Angeles, results indicated that homeless African American and Hispanic women had from two to almost five times greater odds than low-income housed women of having multiple sex partners in the past 6 months. These disparities in risk behavior were accounted for by housing status differences in perceived susceptibility to HIV/AIDS, recent victimization by physical violence, drug use severity, and avoidant coping. Findings provide further evidence that interventions should address a multifaceted context of HIV risk for impoverished women. 相似文献