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991.
992.

Objectives

This study seeks to develop and validate the 19-item German version of the Child Oral Health Impact Profile (COHIP-G19), an instrument to assess the oral health-related quality of life (OHRQoL) in children and adolescents.

Materials and methods

The 19 items of the original English-language COHIP were translated into German using an established forward–backward approach. For the assessment of the psychometric properties of the COHIP-G19, children and adolescents aged 7–17 years came from two samples: 112 patients were consecutively recruited at a university-based orthodontic clinic and 313 came from a convenience sample of students in public schools.

Results

Internal consistency of the COHIP-G19 was satisfactory in both populations (Cronbach’s alpha, 0.78/0.80; average inter-item correlation, 0.16/0.17). The COHIP-G19 summary scores were correlated in the expected direction with a global oral health rating (r?=?0.46/0.40) and two measures for perceived general health (EQ-5D-Y: r?=?0.26/0.29; KIDSCREEN-27: r?=?0.40/0.33). While COHIP-G19 summary scores did not significantly differ with respect to the presence of caries or gingivitis (p?>?0.05), malocclusion and insufficient oral hygiene behavior were related to more impaired OHRQoL, represented in significantly lower COHIP-G19 summary scores in students in public schools (p?<?0.05), but not in orthodontic patients.

Conclusions

While this study revealed some potential to improve reliability and validity in scores of the German version of the COHIP-19, overall, the study proved the instrument has sufficient psychometric properties and is well comparable to the original English-language version.

Clinical relevance

The COHIP-G19 is a valid and reliable instrument to assess OHRQoL in German children and adolescents in clinical and community settings.
  相似文献   
993.
Nevirapine use in HIV-1-infected children   总被引:1,自引:0,他引:1  
OBJECTIVES: To evaluate the safety, efficacy, and clinical, virological, and immunological responses in HIV-1-infected children receiving nevirapine as part of combination antiretroviral therapy (ART). METHODS: A review of case notes of all HIV-1-infected children 96 weeks after starting nevirapine, under a national compassionate access scheme between August 1997 and March 1999 in the UK. Nevirapine was dosed according to the manufacturer's guidelines. RESULTS: Seventy-four children (36 boys, 28 naive to ART) were enrolled, with a median age of 5.2 years, viral load of 5.1 log copies/ml and CD4 lymphocyte count of 13.5%. The liquid formulation and tablets of nevirapine were well tolerated. The proportions of patients achieving undetectable viral load levels at weeks 12, 24, 48 and 96 were 30, 40, 36 and 33%, respectively (intention-to-treat analysis). Of children not on a protease inhibitor who received more than 300 mg/m2/day of nevirapine, 60% had undetectable viral loads at week 96, compared with 17% on recommended doses. Outcomes were similar for patients receiving nevirapine once or twice daily. CD4 cell count percentages increased significantly, with median values sustained above 25% by week 48 onwards. Z-scores for weight and height increased significantly during 96 weeks of treatment. Rash occurred in 20%, of which four (5%) were severe. There were no cases of Stevens-Johnson syndrome. CONCLUSION: Nevirapine was mostly well tolerated, and was associated with encouraging clinical and immunological responses. Virological responses in this cohort support the use of nevirapine doses greater than 300 mg/m2/day, which is higher than currently recommended by the manufacturers.  相似文献   
994.
Maize-targeted mutagenesis: A knockout resource for maize   总被引:15,自引:0,他引:15       下载免费PDF全文
We describe an efficient system for site-selected transposon mutagenesis in maize. A total of 43,776 F1 plants were generated by using Robertson's Mutator (Mu) pollen parents and self-pollinated to establish a library of transposon-mutagenized seed. The frequency of new seed mutants was between 10-4 and 10-5 per F1 plant. As a service to the maize community, maize-targeted mutagenesis selects insertions in genes of interest from this library by using the PCR. Pedigree, knockout, sequence, phenotype, and other information is stored in a powerful interactive database (maize-targeted mutagenesis database) that enables analysis of the entire population and the handling of knockout requests. By inhibiting Mu activity in most F1 plants, we sought to reduce somatic insertions that may cause false positives selected from pooled tissue. By monitoring the remaining Mu activity in the F2, however, we demonstrate that seed phenotypes depend on it, and false positives occur in lines that appear to lack it. We conclude that more than half of all mutations arising in this population are suppressed on losing Mu activity. These results have implications for epigenetic models of inbreeding and for functional genomics.  相似文献   
995.
The objective was to establish the pharmacokinetic properties of porcine factor VIII (pFVIII) at three different doses in a single patient. The patient, born in 1952, had severe haemophilia A and developed an inhibitor to human FVIII (hFVIII) in 1966 aged 14 years. He was first treated with pFVIII in 1980. Apart from a short period of treatment with hFVIII in 1998 which resulted in the reappearance of the inhibitor, pFVIII has been constantly used since 1984. No inhibitor against human or porcine FVIII had been recordable over the 2‐year period prior to the study. Three separate pharmacokinetic studies were performed using a washout period of 72 h and doses of 10 U kg?1, 25 U kg?1, or 50 U kg?1, respectively, with sampling at preinfusion, then at 15 and 30 min and 1, 3, 6, 9, 12 and 24 h postinfusion. The FVIII levels were measured using both plasma derived one stage APTT based assay and chromogenic assay. The results were computed using a model‐independent analysis and a model‐dependent analysis. The respective clearances (mL h?1 kg?1) at doses 50 U, 25 U or 10 U kg?1 were 1.32, 1.33 1.8 (bioassay) and 2.54, 2.93, 9.43 (chromogenic). The respective half‐lives (h) at doses 50 U, 25 U, and 10 U kg?1 were 23.71, 16.54, 25.17 (bioassay) and 15.71, 17.39, and 10.66 (chromogenic). The respective recoveries (u dL?1/u kg?1) at doses 50 U, 25 U, and 10 U kg?1 were 2.32, 2.44, 2.7 (bioassay) and 1.42, 1.16 and 0.9 (chromogenic). It was found that the two compartment model best fitted the curves of the bioassay and a one compartmental model best fitted the curves of the chromogenic assay. The pharmacokinetic studies are the first to be performed at different dose levels and using different assay methods for pFVIII. Using the bioassay, they show a long half‐life and high recovery compared to hFVIII. The differences between the bioassay and the chromogenic assay reflect their different biological basis and are of relevance when potency labelling is performed using chromogenic assay (European Pharmacopeia).  相似文献   
996.
Economic burden of cardiovascular diseases in the enlarged European Union.   总被引:10,自引:0,他引:10  
AIMS: Cardiovascular disease (CVD), together with its main components, coronary heart disease (CHD), and cerebrovascular diseases, is the main source of morbidity and mortality in the European Union (EU), but to date, there has not been any systematic cost-of-illness study to assess the economic impact of CVD in the EU. METHODS AND RESULTS: CVD-related expenditure was estimated using aggregate data on morbidity, mortality, and healthcare resource use. Healthcare costs were estimated from expenditure on primary, outpatient, emergency, and inpatient care, as well as medications. Costs of unpaid care and lost earnings due to morbidity and premature death were included in the study. CVD was estimated to cost the EU Euro 169 billion annually, with healthcare accounting for 62% of costs. Productivity losses and informal care represented 21% and 17% of costs, respectively. CHD represented 27% and cerebrovascular diseases 20% of overall CVD costs. CONCLUSION: CVD is a leading public health problem. Our study is the first to assess the economic burden of CVD across the EU, and our results should help policy makers evaluate policy impact and prioritize research expenditures. However, because of data unavailability, our study has important limitations, which highlight the need for more accurate and comparable CVD-specific information.  相似文献   
997.
Patients with gastrointestinal (GI) haemorrhage use 13.8% of all red blood cell transfusions in England. This review addresses the evidence for red blood cell, fresh frozen plasma and platelet transfusions in acute and chronic blood loss, from both the upper and lower intestinal tract. It reviews the indications for transfusion in GI bleeding, the haematological consequences of massive blood loss and massive transfusion, and the importance of managing coagulopathy in bleeding patients. It also looks at the safety and risks of blood transfusion, and provides clinicians with evidence to reduce unnecessary transfusion. Large controlled clinical trials of blood transfusion specifically in GI bleeding are required, along with further research into the use of adjuvant therapies such as recombinant activated factor VIIa. Changing clinician behaviour to reduce inappropriate blood transfusion remains a key target for future transfusion research.  相似文献   
998.

Background

The American College of Surgeons NSQIP® Surgical Risk Calculator (SRC) was developed to estimate postoperative outcomes. Our goal was to develop and validate an institution-specific risk calculator for patients undergoing major hepatectomy at Carolinas Medical Center (CMC).

Methods

Outcomes generated by the SRC were recorded for 139 major hepatectomies performed at CMC (2008–2016). Novel predictive models for seven postoperative outcomes were constructed and probabilities calculated. Brier score and area under the curve (AUC) were employed to assess accuracy. Internal validation was performed using bootstrap logistic regression. Logistic regression models were constructed using bivariate and multivariate analyses.

Results

Brier scores showed no significant difference in the predictive ability of the SRC and CMC model. Significant differences in the discriminative ability of the models were identified at the individual level. Both models closely predicted 30-day mortality (SRC AUC: 0.867; CMC AUC: 0.815). The CMC model was a stronger predictor of individual postoperative risk for six of seven outcomes (SRC AUC: 0.531–0.867; CMC AUC: 0.753–0.970).

Conclusion

Institution-specific models provide superior outcome predictions of perioperative risk for patients undergoing major hepatectomy. If properly developed and validated, institution-specific models can be used to deliver more accurate, patient-specific care.  相似文献   
999.

Objectives

This study sought to evaluate the feasibility, safety, and efficacy of the Ultraseal device for left atrial appendage closure (LAAC) (Cardia, Eagan, Minnesota) in patients with nonvalvular atrial fibrillation at high bleeding risk.

Background

The Ultraseal device is a novel bulb-and-sail designed LAAC device, with an articulating joint enabling conformability to heterogeneous angles and shapes of appendage anatomy.

Methods

This was a multicenter study including consecutive patients undergoing LAAC with the Ultraseal device at 15 Canadian and European sites. Periprocedural and follow-up events were systematically collected, and transesophageal echocardiography at 45 to 180 days post-procedure was routinely performed in all centers but 3.

Results

A total of 126 patients (mean age 75 ± 8 years; mean CHA2DS2-VASc score 5 ± 2; mean HAS-BLED score 4 ± 1) were included. The device was successfully implanted in 97% of patients. A major periprocedural adverse event occurred in 3 (2.4%) patients (clinically relevant pericardial effusion [n = 1], stroke [n = 1], device embolization [n = 1]). Ninety percent of patients were discharged on single or dual antiplatelet therapy. Follow-up transesophageal echocardiography was available in 89 (73%) patients, with no cases of large (>5 mm) residual leak and 5 (5.6%) cases of device-related thrombosis (all successfully treated with anticoagulation therapy). At a median follow-up of 6 (interquartile range: 3 to 10) months, the rates of stroke and transient ischemic attack were 0.8% and 0.8%, respectively, with no systemic emboli. None of the events occurred in patients with device-related thrombosis.

Conclusions

In this initial multicenter experience, LAAC with the Ultraseal device was associated with a high implant success rate and a very low incidence of periprocedural complications. There were no late device-related clinical events and promising efficacy results were observed regarding thromboembolic prevention at midterm follow-up. Larger studies are further warranted to confirm the long-term safety and efficacy of this novel device.  相似文献   
1000.
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