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Objectives:The purpose of this study was to design, validate, and optimize internally standardized real-time quantitative RT-PCR assays and to identify and avoid problems with assay reliability and examine the impact of an exogenous internal standard.Design and methods:The model system consisted of internally standardized quantitative real-time RT-PCR assays specific for PSA and hK2 mRNA based on time-resolved fluorometric detection of lanthanide chelates.Results:Reproducibility was best when large copy numbers (> 5000 per milliliter blood) were analyzed. Addition of an exogenous target-mimicking internal standard had no significant effect on the reproducibility of the method, but increased the calculated copy numbers by an average of 2-fold.Conclusions:We developed an internally standardized, specific and reproducible real-time RT-PCR analysis method for PSA and hK2 mRNA in circulating cells in the bloodstream. Both PSA and hK2 assays are sufficiently sensitive to detect two LNCaP cells per milliliter whole blood.  相似文献   
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The change in augmentation index following salbutamol inhalation has been applied to evaluate endothelial function. We examined the contribution of salbutamol‐induced increase in heart rate to the observed decrease in augmentation index. Haemodynamics were recorded using whole‐body impedance cardiography and continuous pulse wave analysis from tonometric radial blood pressure. All subjects (n = 335, mean age 46, body mass index 26, 48% men) were without medications with cardiovascular influences. The effects of salbutamol inhalation (0.4 mg) versus the endothelium‐independent agent nitroglycerin resoriblet (0.25 mg) were examined during passive head‐up tilt, as the haemodynamic influences of these compounds depend on body position. Salbutamol decreased augmentation index by ~3‐4% units in supine and upright positions. Although salbutamol moderately increased cardiac index (+4.5%) and decreased systemic vascular resistance (?8.5%), the significant haemodynamic explanatory factors for decreased augmentation index in multivariate analysis were increased supine heart rate, and increased upright heart rate and decreased ejection duration (< 0.001 for all, r= 0.36–0.37). Sublingual nitroglycerin decreased supine and upright augmentation index by ~15% units and ~23% units, respectively. The haemodynamic explanatory factors for these changes in multivariate analysis were increased heart rate, reduced ejection duration and reduced systemic vascular resistance ( 0.021 for all, r2 = 0.22–0.34). In conclusion, the lowering influence of salbutamol on augmentation index may be largely explained by increased heart rate, suggesting that this effect may not predominantly reflect endothelial function.  相似文献   
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Hietasalo P, Seppä L, Niinimaa A, Kallio J, Lahti S, Hausen H. Post‐trial costs, clinical outcomes, and dental service utilization after a randomized clinical trial for caries control among Finnish adolescents. Eur J Oral Sci 2010; 118: 265–269. © 2010 The Authors. Journal compilation © 2010 Eur J Oral Sci The aim of this study was to assess post‐trial treatment costs, clinical outcomes [decayed, missing or filled surfaces (DMFS) scores], and utilization of dental services among adolescents who had participated in a randomized clinical trial (RCT) in Pori, Finland, in 2001–2005. At baseline the children were 11–12 yr of age and had had at least one active initial caries lesion. The children in the experimental group (n = 250) had been exposed to multiple measures for caries control, while those in the control group (n = 247) had received standard dental care. During the post‐trial period (2005–2008), all participants received the standard dental care offered in public dental clinics in Pori. In both groups the costs of treatment procedures and outcomes for the post‐trial period were calculated for each adolescent. Information from patient records was available for 487 adolescents (former experimental n = 246, control n = 241). The mean total costs per adolescent were lower and the clinical outcome was better among the former experimental‐group participants. The differences in mean costs between the groups were statistically significant for preventive and restorative procedures. The utilization of dental services was significantly more regular among the former experimental‐group participants.  相似文献   
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OBJECTIVES: The aim of this study was to investigate the effect of scaling and root planing (SRP) and the maintenance phase of treatment on the gingival crevicular fluid (GCF) matrix metalloproteinase-8 (MMP-8) levels. MATERIALS AND METHODS: Clinical measurements and GCF samples were taken from four sites in 20 adult periodontitis patients before and after SRP and during a 3-month maintenance phase of treatment. MMP-8 levels were measured from GCF samples by time-resolved immunofluorometric assay (IFMA) with monoclonal antibodies. RESULTS: SRP improved the clinical indices as would be predicted, 6.1 mm (SD = 1.4) at baseline compared with 4.3 mm (SD = 1.6) post-treatment (P < 0.001). Attachment level (AL) reduced but not significantly between these two visits 13.4 mm (SD = 2.4) compared with 12.8 mm (SD = 2.4) (P < 0.08) post therapy. GCF MMP-8 levels reduced after initial treatment from 33.8 micro g/30 s sample to 23.5 micro g/30 s, which just failed to reach statistical significance (P = 0.07). However, when MMP-8 levels were expressed as a concentration, the differences following initial therapy were significant (54.1 ng/ micro L at baseline compared with 34.2 ng/micro L post treatment; P < 0.005). The difference, however, between the baseline MMP-8 levels (33.8 ng/30 s) and the final visit (16 ng/30 s) following maintenance was markedly significant (P < 0.001) for both absolute amounts and on a concentration basis. CONCLUSION: In conclusion, clinical improvement following SRP was associated with significant reductions in MMP-8 levels. The GCF concentration of MMP-8 decreased after initial therapy but reduced even more dramatically (approximately 50%) following a 3-month period of maintenance (P < 0.001).  相似文献   
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Pelvic floor training is a well-established treatment for female urinary stress incontinence The purpose of this study was to test four different intravaginal surface electromyography (EMG) probes for biofeedback exercise and measurements. The study design was a comparison test. The study was accomplished in a referral on outpatient clinic. Participants were 9 urinary incontinent patients sent to physiotherapist for pelvic floor muscle exercise and 2 asymptomatic volunteers. The participants were asked to do pelvic floor contractions in supine position. The EMG activity of pelvic floor muscles was measured with four different types of intravaginal probes, and rectal pressure was measured simultaneously with a microtip catheter for controlling the pelvic floor muscle contraction force levels. Main outcome measure was the electrical activity of pelvic floor muscle contractions. The intraprobe correlation coefficients for comparing subsequent measurements ranged from 0.84-0.97, indicating adequate reliability. The results were affected by the location of the measuring electrodes, and the shape and size of the probes. No statistically significant differences were found between different probes. The compliance was best with L- shaped probe B and it gave highest mean EMG values so it was chosen for M- further development as a biofeedback-based home training system.  相似文献   
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Low-molecular-weight (LMW) heparins have been shown to be at least as effective as unfractionated (UF) heparin in the treatment of deep venous thrombosis (DVT) in nonpregnant subjects. LMW heparins have been shown to be safe when used during pregnancy as they do not cross the placenta. Up to now, they have been used mainly in thromboprophylaxis during pregnancy and rarely in the treatment of acute DVT in pregnant women. In a prospective observational study, we compared the effectiveness and safety of the LMW heparin, dalteparin, with UF heparin in the initial treatment (first week) of DVT during pregnancy. After confirmation of DVT by ultrasonography, 10 women were treated with UF heparin (25,430 IU/day, mean) and 21 women with dalteparin (16,000 IU/day, mean) for 7 days and, thereafter, all women were given treatment doses of LMW heparin for another 2 weeks. The dose was then gradually decreased and kept at a high prophylactic dose until delivery. One patient in the dalteparin group had recurrence of DVT 2 weeks after starting the treatment. No differences were observed between the groups in symptoms or bleeding complications during pregnancy and delivery. Our results indicate that LMW heparin is as effective and safe as UF heparin for the first week of treatment, but LMW heparin has the advantage of being easily administered and few laboratory controls are required.  相似文献   
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OBJECTIVE: To examine the acceptability of five nonoxynol-9 (N-9) spermicides. METHODS: We analyzed data from a randomized trial of five products, including three gels containing different amounts of N-9 per dose, a film and a suppository. In the trial, 1536 participants were asked to use the assigned spermicide for 7 months and to complete questionnaires 4 weeks after admission and at discontinuation. RESULTS: Overall, 43% of participants liked their spermicide "very much." This proportion was higher in the three gel groups than in the suppository and film groups. Difficulty with insertion, messiness and discontent with timing of insertion were common complaints in all groups. After adjustment for selected baseline factors, acceptability on the first questionnaire was not related to duration or consistency of subsequent spermicide use or to subsequent time to pregnancy. CONCLUSIONS: In this study, all five spermicides were considered acceptable by most users. Acceptability did not appear to influence spermicide use or pregnancy risk.  相似文献   
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