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1.

Objective

To determine the significance of the English Wikipedia as a source of online health information.

Design

The authors measured Wikipedia's ranking on general Internet search engines by entering keywords from MedlinePlus, NHS Direct Online, and the National Organization of Rare Diseases as queries into search engine optimization software. We assessed whether article quality influenced this ranking. The authors tested whether traffic to Wikipedia coincided with epidemiological trends and news of emerging health concerns, and how it compares to MedlinePlus.

Measurements

Cumulative incidence and average position of Wikipedia® compared to other Web sites among the first 20 results on general Internet search engines (Google®, Google UK®, Yahoo®, and MSN®), and page view statistics for selected Wikipedia articles and MedlinePlus pages.

Results

Wikipedia ranked among the first ten results in 71-85% of search engines and keywords tested. Wikipedia surpassed MedlinePlus and NHS Direct Online (except for queries from the latter on Google UK), and ranked higher with quality articles. Wikipedia ranked highest for rare diseases, although its incidence in several categories decreased. Page views increased parallel to the occurrence of 20 seasonal disorders and news of three emerging health concerns. Wikipedia articles were viewed more often than MedlinePlus Topic (p = 0.001) but for MedlinePlus Encyclopedia pages, the trend was not significant (p = 0.07-0.10).

Conclusions

Based on its search engine ranking and page view statistics, the English Wikipedia is a prominent source of online health information compared to the other online health information providers studied.  相似文献   

2.
Objective:Interleukin-8(IL-8) represents the prototypical chemokine that is made by a wide variety of cell types.Previously studies have suggested that angiotensin Ⅱ(Ang Ⅱ) is involved in atherogenesis through induction ofproinflammatory cytokines such as interleukin-6 or monocyte chemoattractant protein-1 (MCP-1) in vascular smooth muscle cells(VSMCs),while the role orang Ⅱ on IL-8 expression in VSMCs is poorly studied.Methods:In this study,VSMCs were isolated from the thoracic aorta of Sprague-Dawley rats.The expression of smooth muscle α-actin was confirmed by an immunohistochemical method.Semi-quantitative RT-PCR and enzyme-linked immunosorbent assay (ELISA) analyses were conducted to detect IL-8 expression.Results:In the present study we found that Ang Ⅱ significantly increased the expression of IL-8 both at the mRNA and protein levels in rat VSMCs in a dose- and time-dependent manner.Conclusion:These findings suggested that Ang Ⅱ may participate in atherosclerosis through induction of inflammatory mediator in VSMCs.  相似文献   

3.

Objective

Free-text clinical reports serve as an important part of patient care management and clinical documentation of patient disease and treatment status. Free-text notes are commonplace in medical practice, but remain an under-used source of information for clinical and epidemiological research, as well as personalized medicine. The authors explore the challenges associated with automatically extracting information from clinical reports using their submission to the Integrating Informatics with Biology and the Bedside (i2b2) 2008 Natural Language Processing Obesity Challenge Task.

Design

A text mining system for classifying patient comorbidity status, based on the information contained in clinical reports. The approach of the authors incorporates a variety of automated techniques, including hot-spot filtering, negated concept identification, zero-vector filtering, weighting by inverse class-frequency, and error-correcting of output codes with linear support vector machines.

Measurements

Performance was evaluated in terms of the macroaveraged F1 measure.

Results

The automated system performed well against manual expert rule-based systems, finishing fifth in the Challenge's intuitive task, and 13th in the textual task.

Conclusions

The system demonstrates that effective comorbidity status classification by an automated system is possible.  相似文献   

4.
Objective To assess the relationship between diurnal temperature range (DTR) and sudden infant death (SID) between 2001 and 2004 in Shanghai,China.Methods We conducted a time‐stratified case‐crossover analysis to estimate the percent increase of SID associated with changes in DTR after adjustment for daily weather conditions (temperature and relative humidity) and outdoor air pollution.Results DTR was significantly associated with daily SID.An increase of 1 °C in the current‐day (L0) and in the 2‐day moving...  相似文献   

5.
Objective We examined alterations in the expression of tumorigenesis‐related genes in the pituitary gland of rats exposed to electromagnetic pulses (EMP).Methods The global gene expression profiles of the pituitary gland in EMP‐exposed and control groups were detected by cDNA microarray analysis.We then validated and further investigated the reduced expression of two tumorigenesis‐related genes,Pten,and Jund,by assessing their mRNA and protein expression by quantitative real‐time‐PCR,western blotting,and im...  相似文献   

6.

Objective

To measure the uncertainty of temporal assertions like “3 weeks ago” in clinical texts.

Design

Temporal assertions extracted from narrative clinical reports were compared to facts extracted from a structured clinical database for the same patients.

Measurements

The authors correlated the assertions and the facts to determine the dependence of the uncertainty of the assertions on the semantic and lexical properties of the assertions.

Results

The observed deviation between the stated duration and actual duration averaged about 20% of the stated deviation. Linear regression revealed that assertions about events further in the past tend to be more uncertain, smaller numeric values tend to be more uncertain (1 mo v. 30 d), and round numbers tend to be more uncertain (10 versus 11 yrs).

Conclusions

The authors empirically derived semantics behind statements of duration using “ago,” and verified intuitions about how numbers are used.  相似文献   

7.

Background

Polymethylmethacrylate (PMMA) is the most common material used to fabricate interim fixed partial denture (FPD). Several attempts have been made to improve fracture strength of this material with various methods of reinforcement, but its effect on the fracture resistance of interim FPD was not evaluated.

Method

The study was designed in two stages. In the first stage various methods of reinforcement (glass fibre, polyethylene, combination of glass and polyethylene, and stainless steel) for interim FPD of PMMA were used and its effect on the fracture resistance of interim FPD was evaluated by three point bending test using universal testing machine. In the second stage, fibres which showed the highest fracture resistance value was used to ascertain the most appropriate site of placement for reinforcing interim FPD. Comparisons were made with analysis of variance.

Results

Stainless steel and glass fibres showed significantly higher fracture resistance value than polyethylene alone or mixed with glass fibres (P < 0.001). Fibre placement in the occlusal third region of the pontic resulted in higher fracture resistance than the other locations (P < 0.05).

Conclusion

There was a definite improvement in the fracture resistance after reinforcement with fibres and stainless steel. The occlusal third region of the pontic is the most appropriate site of placement for reinforcement in interim FPD.  相似文献   

8.
Objective This work explores the diurnal variation of Solar ultraviolet radiation (UVR) and total solar radiation (TSR) in northeast China,using daily observations of UVR and TSR in Shenyang.Methods UVR and TSR measurements were carried out from March 1st,2006 to December 31st,2009 in Shenyang,Liaoning province,China (41°51' N,123°27' E).Results Both TSR and UVR showed seasonal variation,reaching the highest levels in summer and the lowest in winter.They showed the greatest fluctuation in summer and autumn....  相似文献   

9.

Objective

The purpose of this study is to reassess the projected rate of Electronic Health Record (EHR) diffusion and examine how the federal government's efforts to promote the use of EHR technology have influenced physicians' willingness to adopt such systems. The study recreates and extends the analyses conducted by Ford et al.1 The two periods examined come before and after the U.S. Federal Government's concerted activity to promote EHR adoption.

Design

Meta-analysis and bass modeling are used to compare EHR diffusion rates for two distinct periods of government activity. Very low levels of government activity to promote EHR diffusion marked the first period, before 2004. In 2004, the President of the United States called for a “Universal EHR Adoption” by 2014 (10 yrs), creating the major wave of activity and increased awareness of how EHRs will impact physicians' practices.

Measurement

EHR adoption parameters—external and internal coefficients of influence—are estimated using bass diffusion models and future adoption rates are projected.

Results

Comparing the EHR adoption rates before and after 2004 (2001-2004 and 2001-2007 respectively) indicate the physicians' resistance to adoption has increased during the second period. Based on current levels of adoption, less than half the physicians working in small practices will have implemented an EHR by 2014 (47.3%).

Conclusions

The external forces driving EHR diffusion have grown in importance since 2004 relative to physicians' internal motivation to adopt such systems. Several national forces are likely contributing to the slowing pace of EHR diffusion.  相似文献   

10.
Objective To compare the bacterioplankton communities in streams exposed to pollution of different types. Methods The bacterioplankton communities in three selected heavily polluted streams were investigated by using terminal‐restriction fragment length polymorphism (T‐RFLP) analysis in combination with 16S rRNA gene clone library analysis. Results Both T‐RFLP and 16S rRNA gene clone library revealed a great difference in bacterioplankton community composition in the different streams. Conclusion This work ...  相似文献   

11.
Objective The present study aimed to evaluate the accuracy of the factorial method for estimating energy needs in individuals living in China.Methods Sixteen healthy female adults aged 22.1±1.2 years with a body mass index (kg/m 2) of 20.4±1.7 were selected as subjects.In free-living conditions,energy expenditure (EE) was determined by using the factorial method.At the same time,the doubly labeled water method (DLW) was also used to measure energy expenditure of the subjects and served as the criterion meth...  相似文献   

12.

Objective

Machine learning systems can be an aid to experts performing systematic reviews (SRs) by automatically ranking journal articles for work-prioritization. This work investigates whether a topic-specific automated document ranking system for SRs can be improved using a hybrid approach, combining topic-specific training data with data from other SR topics.

Design

A test collection was built using annotated reference files from 24 systematic drug class reviews. A support vector machine learning algorithm was evaluated with cross-validation, using seven different fractions of topic-specific training data in combination with samples from the other 23 topics. This approach was compared to both a baseline system, which used only topic-specific training data, and to a system using only the nontopic data sampled from the remaining topics.

Measurements

Mean area under the receiver-operating curve (AUC) was used as the measure of comparison.

Results

On average, the hybrid system improved mean AUC over the baseline system by 20%, when topic-specific training data were scarce. The system performed significantly better than the baseline system at all levels of topic-specific training data. In addition, the system performed better than the nontopic system at all but the two smallest fractions of topic specific training data, and no worse than the nontopic system with these smallest amounts of topic specific training data.

Conclusions

Automated literature prioritization could be helpful in assisting experts to organize their time when performing systematic reviews. Future work will focus on extending the algorithm to use additional sources of topic-specific data, and on embedding the algorithm in an interactive system available to systematic reviewers during the literature review process.  相似文献   

13.
Objective Convincing evidence suggests a link between increased risk of nonsyndromic cleft lip with or without cleft palate (NSCL/P) and low intake of folic acid by the mother during pregnancy. The present study was designed to explore if genetic variation in the betaine‐homocysteine methyltransferase (BHMT) gene contributes to NSCL/P. Methods DNA was obtained from 166 individuals with NSCL/P and 285 healthy subjects. Three known single nucleotide polymorphisms (SNPs) present in the BHMT gene (rs651852, rs3...  相似文献   

14.
Natural Language Processing Framework to Assess Clinical Conditions   总被引:1,自引:0,他引:1  

Objective

The authors developed a natural language processing (NLP) framework that could be used to extract clinical findings and diagnoses from dictated physician documentation.

Design

De-identified documentation was made available by i2b2 Bio-informatics research group as a part of their NLP challenge focusing on obesity and its co-morbidities. The authors describe their approach, which used a combination of concept detection, context validation, and the application of a variety of rules to conclude patient diagnoses.

Results

The framework was successful at correctly identifying diagnoses as judged by NLP challenge organizers when compared with a gold standard of physician annotations. The authors overall kappa values for agreement with the gold standard were 0.92 for explicit textual results and 0.91 for intuited results. The NLP framework compared favorably with those of the other entrants, placing third in textual results and fourth in intuited results in the i2b2 competition.

Conclusions

The framework and approach used to detect clinical conditions was reasonably successful at extracting 16 diagnoses related to obesity. The system and methodology merits further development, targeting clinically useful applications.  相似文献   

15.

Objective

Surgical Process Models (SPMs) are models of surgical interventions. The objectives of this study are to validate acquisition methods for Surgical Process Models and to assess the performance of different observer populations.

Design

The study examined 180 SPM of simulated Functional Endoscopic Sinus Surgeries (FESS), recorded with observation software. About 150,000 single measurements in total were analyzed.

Measurements

Validation metrics were used for assessing the granularity, content accuracy, and temporal accuracy of structures of SPMs.

Results

Differences between live observations and video observations are not statistically significant. Observations performed by subjects with medical backgrounds gave better results than observations performed by subjects with technical backgrounds. Granularity was reconstructed correctly by 90%, content by 91%, and the mean temporal accuracy was 1.8 s.

Conclusion

The study shows the validity of video as well as live observations for modeling Surgical Process Models. For routine use, the authors recommend live observations due to their flexibility and effectiveness. If high precision is needed or the SPM parameters are altered during the study, video observations are the preferable approach.  相似文献   

16.

Objective

We explored automated concept-based indexing of unstructured figure captions to improve retrieval of images from radiology journals.

Design

The MetaMap Transfer program (MMTx) was used to map the text of 84,846 figure captions from 9,004 peer-reviewed, English-language articles to concepts in three controlled vocabularies from the UMLS Metathesaurus, version 2006AA. Sampling procedures were used to estimate the standard information-retrieval metrics of precision and recall, and to evaluate the degree to which concept-based retrieval improved image retrieval.

Measurements

Precision was estimated based on a sample of 250 concepts. Recall was estimated based on a sample of 40 concepts. The authors measured the impact of concept-based retrieval to improve upon keyword-based retrieval in a random sample of 10,000 search queries issued by users of a radiology image search engine.

Results

Estimated precision was 0.897 (95% confidence interval, 0.857-0.937). Estimated recall was 0.930 (95% confidence interval, 0.838-1.000). In 5,535 of 10,000 search queries (55%), concept-based retrieval found results not identified by simple keyword matching; in 2,086 searches (21%), more than 75% of the results were found by concept-based search alone.

Conclusion

Concept-based indexing of radiology journal figure captions achieved very high precision and recall, and significantly improved image retrieval.  相似文献   

17.
Objective To produce anti‐19‐Nortestosterone (NT) monoclonal antibodies and identify their immunological characteristics. Methods Hybridomas were prepared by fusing NS0 mouse myeloma cells with splenocytes isolated from immunized BALB/c mice. Noncompetitive and competitive indirect ELISA were employed to screen positive cell clones. A caprylic acid ammonium sulphate (CAAP) method was used to purify NT mAb, and the Batty saturation method was used to determine the affinity constant (Kaff). Results Five hybri...  相似文献   

18.
Objective The study is to investigate the associations between visibility, major air pollutants and daily counts of hospital admission in Shanghai, China. Methods Daily data on hospital admission, visibility, and air pollution during 2005‐2008 were obtained from the Shanghai Insurance Bureau (SHIB), Shanghai Meteorological Bureau, and Shanghai Environmental Monitoring Center, respectively. The generalized additive model (GAM) with penalized splines was used to examine the associations between daily visibili...  相似文献   

19.
Objective To determine if global warming has an impact on the evolution of hemagglutinins from influenza A viruses, because both global warming and influenza pandemics/epidemics threaten the world. Methods 4 706 hemagglutinins from influenza A viruses sampled from 1956 to 2009 were converted to a time‐series to show their evolutionary process and compared with the global, northern hemisphere and southern hemisphere temperatures, to determine if their trends run in similar or opposite directions. Point‐to‐po...  相似文献   

20.
Objective Bloom’s syndrome is an autosomal recessive disorder characterized by genomic instability and a predisposition to many cancers. Mutations of the BLM gene (encoding a BLM helicase) may form a structure of the etiology of this disease. As a global pollutant, mercury poses a major threat to human health. The current study was conducted to elucidate the effects of Hg 2+ on the structure and activity of BLM642‐1290 recombinant helicase, and to further explore the molecular mechanisms of mercury toxicity...  相似文献   

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