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The study objective was clinical assessment of the efficacy of photodynamic therapy (PDT) in the treatment of oral lichen planus (OLP). There were 23 patients aged 31–82 included in the study with oral lichen planus diagnosed clinically and histopathologically. In all patients photodynamic therapy was performed with the use of chlorin e6 (Photolon®), containing 20 % chlorin e6 and 10 % dimethyl sulfoxide as a photosensitizer. PDT was performed using a semiconductor laser, with power up to 300 mW and a wavelength of 660 nm. A series of illumination sessions was conducted with the use of superficial light energy density of 90 J/cm2. Changes of lesion size were monitored at one, two, five, and ten PDT appointments from the series of ten according to the authors' own method. The sizes of clinical OLP lesions exposed to PDT were reduced significantly (on average by 55 %). The best effects were observed for the lesions on the lining mucosa (57.6 %). The therapy was statistically significantly less effective when masticatory mucosa was affected (reduction, 30.0 %). Due to substantial efficacy and noninvasiveness, PDT can be useful in the treatment of OLP lesions.  相似文献   
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Aims To determine whether collaborative behavioral management (CBM) reduces substance use, crime and re‐arrest among drug‐involved parolees. Design Step'n Out was a randomized behavioral trial of CBM versus standard parole (SP) during 2004–08. CBM adapted evidence‐based role induction, behavioral contracting and contingent reinforcement to provide parole officer/treatment counselor dyads with positive tools in addition to sanctions to manage parolees' behavior over 12 weeks. Setting Six parole offices in five states in the USA. Participants Parolee volunteers with a mandate for addiction treatment and a minimum of 3 months of parole (n = 476). Follow‐up was 94% at 3 months and 86% at 9 months. Measurements Drug use and crime in a given month from calendar interviews 3 and 9 months after parole initiation, and re‐arrests from criminal justice administrative data. Findings The CBM group had fewer months in which they used their primary drug [adjusted risk ratio (ARR) 0.20, 95% confidence interval (CI): 0.05, 0.78, P = 0.02] and alcohol (ARR 0.38, 95% CI: 0.22, 0.66, P = 0.006) over follow‐up. CBM had its greatest effects among parolees who reported marijuana or another ‘non‐hard’ drug as their primary drug; parolees who preferred stimulants or opiates did not benefit. No differences were seen in total crime, re‐arrests or parole revocations. Conclusions Collaborative behavioral management may reduce substance use among primary marijuana or other ‘non‐hard’ drug‐using parolees without increasing revocations. Because the majority of drug violation arrests in the United States are for marijuana, these findings have important implications for the management of a substantial proportion of the US community correctional population.  相似文献   
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Aim To explore the facilitators of long‐term hepatitis C avoidance among people who inject drugs. Design We employed a qualitative life history design. Setting Recruitment took place through low‐threshold drug services and drug user networks in South East and North London. Participants were interviewed at the recruitment services or in their homes. Participants The sample comprised 35 people who inject drugs, 20 of whom were hepatitis C antibody‐negative. Participants' average injecting trajectory was 19 years (6–33), with 66% primarily injecting heroin, and 34% a crack and heroin mix. Nine (26%) of the sample were female and the average age was 39 years (23–53). Measurements Two interviews were conducted with each participant, with the second interview incorporating reference to a computer‐constructed life history time‐line. Interview accounts were audiorecorded, transcribed verbatim and analysed thematically. Findings Hepatitis C risk awareness was recent and deprioritized by the majority of participants. The facilitation of venous access and care was an initial and enduring rationale for safe injecting practices. Difficult venous access resulted in increased contamination of injecting environments and transitions to femoral injecting. Participants expressed an unmet desire for non‐judgemental venous access information and advice. Conclusions Harm reduction interventions which attend to the immediate priorities of people who inject drugs, such as venous access and care, have the potential to re‐engage individuals who are jaded or confused by hepatitis C prevention messages.  相似文献   
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The main aim of the present study was the synthesis of an oligonucleotide-based material with high chemical stability, repeatability and specificity to complementary oligonucleotides. The oligonucleotides were attached to a silica gel surface modified with amino acids during one-step synthesis. The amount of the oligonucleotides immobilized on the support surface had an impact on adsorption effectiveness, due to steric interference. The adsorption capacity corresponds to 4.7 μg of complementary oligonucleotide per 1 mg of material, which reflects 50% of immobilized oligonucleotides. The presented results contain comprehensive studies on hybridization and release of fully complementary, partially complementary, non-complementary and antisense oligonucleotides from the newly synthesized adsorbent. The salt concentration and time period were the most influential parameters in the case of adsorption, while high temperature and low salt content were indispensable for effective desorption. Selectivity studies revealed that the adsorption percentage increases with the decreasing number of base mismatches. Consequently, the desorption of low complementarity oligonucleotides was always greater in comparison with the fully complementary sequence. Furthermore, it was shown that oligonucleotide-based materials may be successfully used for the extraction of antisense oligonucleotides and their metabolites from serum samples with recoveries ranging between 65 and 73%.

The main aim of the present study was the synthesis of an oligonucleotide-based material with high chemical stability, repeatability and specificity to complementary oligonucleotides.  相似文献   
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Background. The aim of this study was to evaluate the influence of oral vitamin E therapy on serum concentrations of several markers of micro-inflammation and cardiovascular disease in chronic hemodialysis (HD) patients. Methods. 29 HD patients were randomized into two groups: 15 patients were treated orally with 400mg of vitamin E daily for a period of five weeks, and 14 patients received no antioxidant supplementation. Before and after vitamin E therapy, serum concentrations of vitamin E (high-performance liquid chromatography), pregnancy-associated plasma protein-A (immunochemical – TRACE assay), C-reactive protein (nephelometry), intercellular adhesion molecule-1 (ELISA), and E-selectin (ELISA) were measured. HD patients were compared with 16 healthy controls. Results. Baseline serum concentrations of PAPP-A and CRP were significantly higher in HD patients than in healthy controls (PAPP-A: 26.23±11.94 vs. 11.41±1.94 mIU/L, p<0.001; CRP: 5.20±3.50 vs. 3.40±3.80 mg/L, p<0.05). After five weeks of oral vitamin E intake, serum PAPP-A, CRP, ICAM-1, and E-selectin concentrations remained unchanged in both groups of HD patients. Conclusion. Chronic micro-inflammation in HD patients is documented by the elevation of CRP and PAPP-A. A daily oral dose of 400 mg of vitamin E does not seem to be able to reduce enhanced oxidative stress and micro-inflammation in chronic HD patients.  相似文献   
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