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41.
Background context1H magnetic resonance imaging (MRI) of the spine can rule out common causes of low back pain (LBP), such as disc protrusions or nerve root compression; however, no significant causal relation exists between morphology and the extent of symptoms. Functional MRI techniques, such as 23Na, may provide additional information, allowing indirect assessment of vertebral glycosaminoglycan concentrations, decreases in which are associated with early degenerative changes.PurposeTo evaluate 23Na-MRI of asymptomatic healthy volunteers and symptomatic patients with LPB and correlate the results to the Pfirrmann classification of MRI disc morphology.Study designRetrospective cohort study at an academic medical center.Patient sampleTwo groups were studied: (1) 55 healthy volunteers (31 men, 24 women; mean age 28.8 years) and (2) 12 patients (6 men, 6 women; mean age: 35.3 years) with a recent history of LBP.MethodsLumbar spines of the aforementioned groups were examined on a 3.0 T MRI scanner with morphological 1H and 23Na imaging. Intervertebral disc (IVD) 23Na at each level was normalized (23Nanorm). Distribution and differences between mean 23Nanorm corresponding to each Pfirrmann classification were evaluated in the two study groups (analysis of variance). Linear correlations between 23Nanorm, body mass index (BMI), and age were assessed (Pearson correlation coefficient). Gender-dependent differences were evaluated (paired t test).Outcome measuresPhysiological measure: IVD 23Nanorm as determined by 23Na-MRI.ResultsA normal distribution of 23Nanorm was confirmed for both groups (p=.072 and p=.073, respectively). The mean Pfirrmann score statistically significantly differed between them (p<.0001). 23Nanorm was statistically significantly reduced in degenerated IVDs (Pfirrmann scores 4+5) (p<.0001). No statistically significant differences were seen for the mean 23Nanorm of IVDs with the same Pfirrmann score in healthy volunteers and patients (.469<p<.967). Age (0.007<R2<0.202) and BMI (0.074<R2<0.288) showed either weak or no correlation to 23Nanorm. Mean 23Nanorm was significantly (p=.0002) greater in women relative to men.ConclusionsThe results underline the feasibility and robustness of 23Na-MRI of human IVDs and affirm, in a large cohort, decreases in 23Na IVD content seen with disc degeneration.  相似文献   
42.

Background

Cyclo-oxygenase-2 (COX-2), an inducible enzyme expressed in areas of inflammation, is a target of interest for colorectal cancer therapy. Currently, the predictive significance of COX-2 in colorectal cancer remains unclear.

Methods

Tissue microarrays were constructed using 118 colon cancer and 85 rectal cancer specimens; 44 synchronous metastatic colon cancer and 22 rectal cancer lymph nodes were also evaluated. COX-2 expression was assessed by immunohistochemistry. Univariate analysis was used to determine the predictive significance of clinicopathologic variables. Overall survival, disease-specific survival, and disease-free survival were the main outcomes examined.

Results

COX-2 was found to be expressed in 93% of colon cancers and 87% of rectal cancers. Decreased COX-2 expression was related to decreased disease-specific survival (P = .016) and decreased disease-free survival (P = .019) in the rectal cancer cohort but not in the colon cancer cohort.

Conclusions

COX-2 expression has predictive utility for management of rectal but not colon cancer.  相似文献   
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Purpose

Injury records from Emergency Departments (EDs) have been studied over the last decade as part of the work of the National Violence Surveillance Network (NVSN) and provide information about local, regional and national violence levels and trends in England and Wales. The purpose of the current study is to evaluate overall, gender, age-specific and regional trends in community violence in England and Wales from an ED perspective from January 2005 to December 2009.

Methods

Violence-related injury data were collected prospectively in a stratified sample of 77 EDs (Types 1, 3 and 4) in the nine Government Office Regions in England and in Wales. All 77 EDs were recruited on the basis that they had implemented and continued to comply with the provisions of the 1998 Data Protection Act and Caldicott guidance. Attendance date, age and gender of patients who reported injury in violence were identified using assault-related attendance codes, specified at the local level. Time series statistical methods were used to detect both regional and national trends.

Results

In total 221,673 (163,384 males: 74%) violence-related attendances were identified. Overall estimated annual injury rate was 6.5 per 1000 resident population (males 9.8 and females 3.4 per 1000). Violence affecting males and females decreased significantly in England and Wales over the 5-year period, with an overall estimated annual decrease of 3% (95% CI: 1.8–4.1%, p < 0.05). Attendances decreased significantly for both genders across four out of the five age groups studied. Attendances were found to be highest during the months of May and July and lowest in February. Substantial differences in violence-related ED attendances were identified at the regional level.

Conclusions

From this ED perspective overall violence in England and Wales decreased over the period 2005–2009 but increased in East Midlands, London and South West regions. Since 2006, overall trends according to Crime Survey for England and Wales (CSEW), police and ED measures were similar, though CSEW and ED measures reflect far greater numbers of violent incidents than police data. Causes of decreases in violence in regions need to be identified and shared with regions where violence increased.  相似文献   
46.

Objective

Assess factors that influence both the patient and the physician in the setting of minor head injury in adults and the decision-making process around CT utilization.

Methods

This is a convenience sample survey study of adult minor head injury patients (GCS 15) and their physicians regarding factors influencing the decision to use CT to evaluate for intra-cranial haemorrhage. Once a head CT was ordered and before the results were known, both the patient and physician were given a one-page survey asking questions about their concern for injury and rationale for CT use. CT results and surveys were then recorded in a centralized database and analyzed.

Results

584 subjects were enrolled over the 27-month study period. The rate of any intra-cranial haemorrhage was 3.3%. Both the physicians (6% pre-test estimate) and the patients (22% pre-test estimate) over-estimated risk for haemorrhage. Clinical decision rules were not met in 46% of cases where CT was used. Physicians listed an average of 5 factors from a list of 9 that influenced their decision to order CT. Patients listed an average of 1.7 factors influencing their decision to present to the Emergency Department for evaluation. Many patients felt cost (45%) and low risk stratification (34%) should weigh heavily in the decision to use CT. If asked to limit CT utilization, physicians were able to identify a group with less than 2% risk of injury.

Conclusions

Patients with low risk of intra-cranial injury continue to be evaluated by CT. Physician decision-making around the use of CT to evaluate minor head injury is multi-factorial. Shared decision-making between the patient and the physician in a low risk minor head injury encounter shows promise as a method to reduce CT utilization in this low risk cohort.  相似文献   
47.

Purpose

The pediatric NSQIP program is in the early stages of facilitated surgical quality improvement for children. The objective of this study is to describe the initial experience of the first Canadian Children’s Hospital participant in this program.

Method

Randomly sampled surgical cases from the “included” case list were abstracted into the ACS-NSQIP database. These surgical procedure-specific data incorporate patient risk factors, intraoperative details, and 30 day outcomes to generate annual reports which provide hierarchical ranking of participant hospitals according to their risk-adjusted outcomes.

Results

Our first risk-adjusted report identified local improvement opportunities based on our rates of surgical site infection (SSI) and urinary tract infection (UTI). We developed and implemented an engagement strategy for our stakeholders, performed literature reviews to identify practice variation, and conducted case control studies to understand local risk factors for our SSI/UTI occurrences. We have begun quality improvement activities targeting reduction in rates of SSI and UTI with our general surgery division and ward nurses, respectively.

Conclusions

The NSQIP pediatric program provides high quality outcome data that can be used in support of quality improvement. This process requires multidisciplinary teamwork, systematic stakeholder engagement, clinical research methods and process improvement through engagement and culture change.  相似文献   
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Anonymous nuclear markers were developed for Seychelles caecilian amphibians. Using a previously published bioinformatics pipeline (developed for Roche 454 data), 36 candidate anonymous nuclear loci (ANL) of at least 180 bp length were identified from Illumina MiSeq next generation sequencing data for five Seychelles species. We designed primer pairs for the 36 candidate ANL and tested these by PCR and Sanger sequencing. Seven ANL amplified and sequenced well for at least five of the six nominal Seychelles caecilian species (in three genera), and represent potentially useful markers for systematics and conservation.  相似文献   
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