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At least 469 records · Page 26Linked to original sources
PubMed2006

The association between anxiety and chronic pain after whiplash injury: gender-specific effects.

OBJECTIVE: There is increasing evidence to suggest that anxiety is related more strongly to chronic pain experience in men relative to women. The aim of the present study was to examine for the first time gender-specific associations between anxiety and chronic pain experience in men and women exposed to whiplash trauma. METHOD: One thousand seven hundred and nine people with whiplash (1349 women, 360 men) belonging to the Danish Society for Polio, Traffic, and Accident Victims completed a battery of questionnaires measuring demographic, psychologic, and pain-related factors (including frequency of painful episodes, level of pain interference, number of anatomic regions in which pain was felt, and the level of general disability). RESULTS: Anxiety was found to be positively related to the level of general disability to a significantly stronger magnitude in men compared with women. A trend difference in correlation magnitude was also found between men and women when comparing anxiety with pain frequency, with the magnitude of correlation being higher in men. DISCUSSION: The stronger association between anxiety and symptoms of whiplash trauma in men compared with women may be due to gender differences in the attribution of anxiety-related autonomic arousal as symptoms of whiplash injury. Alternatively, anxiety may differentially affect the willingness of men and women to report pain and other health indices. Anxiety is an important factor in understanding gender differences in whiplash-related symptoms such as chronic pain and disability, and requires further investigation.

Adult↗
PubMed2003

Common statistical methods in orthopaedic clinical studies.

We discuss the statistical representation and management of random error in orthopaedic clinical studies. Descriptive studies (such as case series) collect information about a sample that may be generalized to describe a population. Typically this description is in the form of summary statistics, such as means, proportions, or rates. Error in these variables may be represented by confidence intervals. Correlation and regression are techniques for investigation of the relationship between two or more variables. Descriptive statistics, comparisons of groups, especially hypothesis tests, and assessment of association including correlation and regression are important statistical concepts for clinicians involved in the conduct or appraisal of orthopaedic clinical research.

Chi-Square Distribution↗
PubMed2002

Evidence for trends in UK flooding.

Recent major flooding in the UK has raised concern that climate change is causing increases in flood frequency and flood magnitude. This paper considers whether UK flood data provide evidence of increasing trends in fluvial floods. The analysis examines both local and national flood series and investigates the effect of climate variability on trend detection. The results suggest that there have been trends towards more protracted high flows over the last 30-50 years, but that this could be accounted for as part of climatic variation rather than climate change. There is no statistical evidence of a long-term trend in flooding over the last 80-120 years. Thus, although climate change could be influencing floods, direct analysis of flood records does not yet provide proof.

Climate↗
PubMed2004

Quantification of variability and uncertainty for censored data sets and application to air toxic emission factors.

Many environmental data sets, such as for air toxic emission factors, contain several values reported only as below detection limit. Such data sets are referred to as "censored." Typical approaches to dealing with the censored data sets include replacing censored values with arbitrary values of zero, one-half of the detection limit, or the detection limit. Here, an approach to quantification of the variability and uncertainty of censored data sets is demonstrated. Empirical bootstrap simulation is used to simulate censored bootstrap samples from the original data. Maximum likelihood estimation (MLE) is used to fit parametric probability distributions to each bootstrap sample, thereby specifying alternative estimates of the unknown population distribution of the censored data sets. Sampling distributions for uncertainty in statistics such as the mean, median, and percentile are calculated. The robustness of the method was tested by application to different degrees of censoring, sample sizes, coefficients of variation, and numbers of detection limits. Lognormal, gamma, and Weibull distributions were evaluated. The reliability of using this method to estimate the mean is evaluated by averaging the best estimated means of 20 cases for small sample size of 20. The confidence intervals for distribution percentiles estimated with bootstrap/MLE method compared favorably to results obtained with the nonparametric Kaplan-Meier method. The bootstrap/MLE method is illustrated via an application to an empirical air toxic emission factor data set.

Air↗
PubMed1995

The effect of human chorionic gonadotropin (HCG) in the treatment of obesity by means of the Simeons therapy: a criteria-based meta-analysis.

1. A meta-analysis was conducted to assess if there is scientific ground for the use of human chorionic gonadotropin (HCG) as adjunctive therapy in the treatment of obesity. 2. Published papers relating to eight controlled and 16 uncontrolled trials that measured the effect of HCG in the treatment of obesity were traced by computer-aided search and citation tracking. 3. The trials were scored for the quality of the methods (based on four main categories: study population, interventions, measurement of effect, and data presentation and analysis) and the main conclusion of author(s) with regard to weight-loss, fat-redistribution, hunger, and feeling of well-being. 4. Methodological scores ranged from 16 to 73 points (maximum score 100), suggesting that most studies were of poor methodological quality. Of the 12 studies scoring 50 or more points, one reported that HCG was a useful adjunct. The studies scoring 50 or more points were all controlled. 5. We conclude that there is no scientific evidence that HCG is effective in the treatment of obesity; it does not bring about weight-loss of fat-redistribution, nor does it reduce hunger or induce a feeling of well-being.

Body Weight↗
PubMed2006

Contribution of virus-induced lysis and protozoan grazing to benthic bacterial mortality estimated simultaneously in microcosms.

In contrast to the water column, the fate of bacterial production in freshwater sediments is still a matter of debate. Thus, the importance of virus-induced lysis and protozoan grazing of bacteria was investigated for the first time simultaneously in a silty sediment layer of a mesotrophic oxbow lake. Microcosms were installed in the laboratory in order to study the dynamics of these processes over 15 days. All microbial and physicochemical parameters showed acceptable resemblance to field data observed during a concomitant in situ study, and similar conclusions can be drawn with respect to the quantitative impact of viruses and protozoa on the bacterial compartment. Viral decay rates ranged from undetectable to 0.078 h(-1) (average, 0.033 h(-1)), and the control of bacterial production from below the detection limit to 36% (average, 12%). The contribution of virus-induced lysis of bacteria to the dissolved organic matter pool as well as to benthic bacterial nutrition was low. Ingestion rates of protozoan grazers ranged from undetectable to 24.7 bacteria per heterotrophic nanoflagellate (HNF) per hour (average, 4.8 bacteria HNF(-1) h(-1)) and from undetectable to 73.3 bacteria per ciliate per hour (average, 11.2 bacteria ciliate(-1) h(-1)). Heterotrophic nanoflagellate and ciliates together cropped up to 5% (average, 1%) of bacterial production. The viral impact on bacteria prevailed over protozoan grazing by a factor of 2.5-19.9 (average, 9.5). In sum, these factors together removed up to 36% (average, 12%) of bacterial production. The high number of correlations between viral and protozoan parameters is discussed in view of a possible relationship between virus removal and the presence of protozoan grazers.

Animals↗
PubMed2006

Relationship of deep white matter hyperintensities and cerebral blood flow in severe carotid artery stenosis.

Leukoaraiosis (LA) has been associated with abnormalities of both large and small blood vessels. This study attempts to clarify the pathogenesis of LA by testing the hypothesis that increased frequency of LA with occlusive extra-cranial arterial disease results directly from global reduction in cerebral blood flow (CBF). Thirty-five normal subjects and 55 patients with carotid stenosis (>70%) were studied using MR. CBF was measured using phase contrast MR angiography and LA was scored using previously validated scoring system. Patients were divided into those with evidence of previous infarction on MRI and those without. LA was more severe in patients than in normal subjects (P<0.01) and correlated with age in normal subjects but not in patients. CBF in patients with (809+/-214 ml/min) and without infarction (mean 792+/-181 ml/min) was significantly lower than in normal subjects (mean 1073+/-194 ml/min). There was no correlation between the severity of LA and measured CBF in any group. The severity of LA is greater in patients with severe carotid stenosis but is not correlated to reductions in CBF. This suggests that microvascular abnormality is the dominant pathogenetic factor in LA even in the presence of severe stenotic/occlusive large vessel disease.

Aged↗
PubMed2006

Relationship between clinical signs and symptoms and nasopharyngeal flora in acute otitis media.

Possible links between the clinical signs and symptoms of acute otitis media and the composition of the nasopharyngeal flora were investigated by reviewing the files of 1807 children enrolled in four randomised, multicentre trials. A standard protocol was used, nasopharyngeal samples were cultured, and signs and symptoms were recorded. Carriage of Haemophilus influenzae was associated positively with conjunctivitis (OR 4.83, 95% CI 3.76-6.20) and negatively with fever (OR 0.69, 95% CI 0.56-0.86). Carriage of pneumococci was associated positively with fever (OR 1.32, 95% CI 1.08-1.63) and negatively with conjunctivitis (OR 0.50, 95% CI 0.40-0.63).

Carrier State↗
PubMed2000

Candida albicans colonization of surface-sealed interim soft liners.

PURPOSE: This in-vivo investigation evaluated the effect of 2 denture sealer agents on the microbial colonization of a newly placed soft interim denture liner during a period of 14 days. MATERIALS AND METHODS: An interim soft denture liner (Coe-Soft; GC America, Alsip, IL) was coated with 2 different denture surface sealants (Palaseal [Heraeus Kulzer, Irvine, CA] and Mono-Poly [Plastodent, New York, NY]). Three rectangular wells of 1 cm wide x 2 cm long x 2 mm deep were placed in the intaglio of 10 maxillary complete dentures and filled with the soft liner material. The soft liner surface was treated with Palaseal (first well) and Mono-Poly (second well), and the unsealed (third well) was used as a control. These were exposed to the oral cavity for 14 days. The effect the sealant had in the prevention of Candidal colonization in vivo of the soft liner material was evaluated. Microbiological specimens were recovered from all samples and cultivated. Microbiological data from the control and 2-test samples in each denture were tabulated, and statistical analyses were performed. RESULTS: This investigation showed clear differences (p <.001) between the sealed and unsealed soft liners. The sealed material showed significantly less colonization by yeast and bacteria. Intercomparison of the surface denture sealers, Palaseal versus Mono-Poly, showed no statistically significant differences (p < .005) in total yeast or bacterial colonization. CONCLUSION: Coating of Coe-Soft denture liner with either Palaseal or Mono-Poly significantly decreased yeast and bacterial colonization. .

Adult↗