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Free-running locomotor activity and eclosion rhythms ofDrosophila melanogaster, mutant at thedisconnected (disco) locus, are substantially different from the wild-type phenotype. Initial periodogram analysis revealed little or no rhythmicity (Dushayet al., 1989). We have reanalyzed the locomotor activity data using high-resolution signal analysis (maximum-entropy spectral analysis, or MESA). These analyses, corroborated by autocorrelograms, uncovered significant residual circadian rhythmicity and strong ultradian rhythms in most of the animals tested. In this regard thedisco mutants are much like flies expressing mutant alleles of theperiod gene, as well as wild-type flies reared throughout life in constant darkness. We hypothesize that light normally triggers the coupling of multiple ultradian oscillators into a functional circadian clock and that this process is disrupted indisco flies as a result of the neural lesion.This work was supported in part by NIH Grant FM-33205.  相似文献   
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Hereditary hearing impairment affects about 1 in 1000 newborns. In most cases hearing loss is non-syndromic with no other clinical features, while in other families deafness is associated with specific clinical abnormalities. Analysis of large families with non-syndromic and syndromic deafness have been used to identify genes or gene locations that cause hearing impairment. The present report describes a large Norwegian family with autosomal dominant non-syndromic, progressive high tone hearing loss with linkage to 1q21-q23. A maximum LOD score of 7.65 (theta = 0.00) was obtained with the microsatellite marker D1S196. Analysis of recombinant individuals maps the deafness gene (DFNA7) to a 22 cM region between D1S104 and D1S466. The region contains several attractive candidate genes. This report supports the idea of extensive genetic heterogeneity in hereditary hearing impairment and represents the first localization of a deafness gene in a Norwegian family.   相似文献   
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A population based hybrid design combining element of cohort and cross-sectional approach was used to develop a simple clinical algorithm to predict individual probability of developing hypertension (systolic BP > 140 mm Hg and/or diastolic BP > 90 mmHg). 3615 soldiers initially normotensive at the time of induction into high altitude, were studied by systematic random sampling. Multiple logistic regression analysis showed a high significant association between hypertension and age, body mass index (BMI), tobacco smoking and alcohol consumption. Using the constant/coefficient values obtained from the logistic model and the receiver operating characteristics (ROC) curve analysis, the following predictive rule was developed – To the age in years, add (BMIx 3.86); also add 5.53 if he is a smoker; and add 19.81 if he consumes alcohol. If the total exceeds 142, the individual is at high risk of developing hypertension. This algorithm carries a sensitivity of 68.2% and specificity of 78.5%.KEY WORDS: Hypertension, High altitude  相似文献   
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ObjectivesTo determine whether ankle proprioception differs by competitive level and is related to years of surf-specific experience. A secondary objective of this study is to further compare the physical capacities and abilities that may differentiate between the competitive levels of surfing.DesignCross-sectional.MethodsTwelve junior-elite (currently competing at a state level or higher and 12–18 years of age), twelve senior-elite (currently competing at a national level and/or the World Qualifying Series and over 16 years of age), and twelve recreational surfers (minimum of two years surfing experience; actively surfing at least once a week and over 18 years of age) were recruited for this study. All participants completed a pre-exercise medical questionnaire, anthropometric assessment, ankle dorsiflexion range of motion assessment, medial-lateral ankle proprioception assessment, countermovement jump, squat jump, isometric mid-thigh pull and drop-and-stick.ResultsSenior-elite surfers had large and significantly better ankle proprioception and range of motion than junior-elite and recreational surfers. However, the relationship between years of surf-specific experience and ankle proprioception was small and non-significant. Better drop-and-stick performance, indicated by lower relative peak force, was present in the senior-elite compared to the junior-elite and recreational groups.ConclusionsThe results indicate that medial-lateral ankle proprioception is a distinguishing characteristic of senior-elite surfers and therefore, may be a critical ability for competitive success. Greater ankle range of motion and the ability to attenuate energy to reduce landing force may be developed through long-term training commensurate with competitive surfing.  相似文献   
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Background

Two decades of research has established the positive effect of using patient-targeted decision support interventions: patients gain knowledge, greater understanding of probabilities and increased confidence in decisions. Yet, despite their efficacy, the effectiveness of these decision support interventions in routine practice has yet to be established; widespread adoption has not occurred. The aim of this review was to search for and analyze the findings of published peer-reviewed studies that investigated the success levels of strategies or methods where attempts were made to implement patient-targeted decision support interventions into routine clinical settings.

Methods

An electronic search strategy was devised and adapted for the following databases: ASSIA, CINAHL, Embase, HMIC, Medline, Medline-in-process, OpenSIGLE, PsycINFO, Scopus, Social Services Abstracts, and the Web of Science. In addition, we used snowballing techniques. Studies were included after dual independent assessment.

Results

After assessment, 5322 abstracts yielded 51 articles for consideration. After examining full-texts, 17 studies were included and subjected to data extraction. The approach used in all studies was one where clinicians and their staff used a referral model, asking eligible patients to use decision support. The results point to significant challenges to the implementation of patient decision support using this model, including indifference on the part of health care professionals. This indifference stemmed from a reported lack of confidence in the content of decision support interventions and concern about disruption to established workflows, ultimately contributing to organizational inertia regarding their adoption.

Conclusions

It seems too early to make firm recommendations about how best to implement patient decision support into routine practice because approaches that use a ‘referral model’ consistently report difficulties. We sense that the underlying issues that militate against the use of patient decision support and, more generally, limit the adoption of shared decision making, are under-investigated and under-specified. Future reports from implementation studies could be improved by following guidelines, for example the SQUIRE proposals, and by adopting methods that would be able to go beyond the ‘barriers’ and ‘facilitators’ approach to understand more about the nature of professional and organizational resistance to these tools. The lack of incentives that reward the use of these interventions needs to be considered as a significant impediment.
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