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991.
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Objective

To estimate the prevalence of chronic neck pain in North Carolina, to describe health care use (providers, treatments, and diagnostic testing) for chronic neck pain, and to correlate health care use with the current best evidence.

Methods

We used data from a cross‐sectional telephone survey of a representative sample of North Carolina households in 2006. A total of 5,357 households were contacted in 2006 to identify 141 noninstitutionalized adults ages ≥21 years with chronic neck pain and no chronic low back pain. The subjects were interviewed about their health and health care use (i.e., provider, tests, and treatments). Patterns of health care use were compared with current systematic reviews.

Results

The estimated prevalence of chronic neck pain in 2006 among noninstitutionalized individuals for the state of North Carolina was 2.2% (95% confidence interval [95% CI] 1.7–2.6). Individuals with chronic neck pain were middle‐aged (mean age 48.9 years) and the majority of subjects were women (56%) and non‐Hispanic white (81%). The subjects saw a mean of 5.21 (95% CI 4.8–5.6) provider types and had a mean of 21 visits. The types of treatments subjects reported varied, with treatments such as electrotherapy stimulation (30.3%), corsets or braces (20.9%), massage (28.1%), ultrasound (27.3%), heat (57.0%), and cold (47.4%) having unclear or little benefit based on the current best available reviews.

Conclusion

Based on the current evidence for best practice, our findings indicate overutilization of diagnostic testing, narcotics, and modalities, and underutilization of effective treatments such as therapeutic exercise.  相似文献   
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Multiple breath inert gas washout (MBW) is gaining popularity for measurements of resting lung volume and ventilation inhomogeneity. Test reproducibility is an important determinant of the clinical applicability of diagnostic tests. The between‐test reproducibility of variables derived from MBW tests in newborn infants is unknown. We aimed to determine the within‐test repeatability and short‐term between‐test reproducibility of MBW variables in unsedated preterm infants. We hypothesized that measurements obtained within a 3‐day interval in clinically stable preterm infants would be reproducible and suitable for use as an objective clinical outcome measurement. In this cross‐sectional observational study, clinically stable hospitalized preterm infants whose parents had given informed consent for MBW studies were tested twice within 72 hr during quiet, unsedated sleep. Functional residual capacity (FRC), lung clearance index (LCI), and the first and second to zeroeth moment ratios (M1:M0; M2:M0) were computed from MBW traces obtained using a mainstream ultrasonic flowmeter and 4% sulphur hexafluoride (MBWSF6). Within‐test repeatability and between‐test reproducibility were determined. Within‐test repeatability (expressed as a coefficient of variability (Cv)) for differences between two and four replicate measurements on the same test occasion, were 9.3% (FRC), 9.0% (LCI), 7.6% (M1:M0), and 15.6% (M2:M0), respectively. The within‐test Cv's were not statistically different to the between‐tests Cv's, which were 7.7% (FRC), 10.3% (LCI), 6.1% (M1:M0), and 13.0% (M2:M0), respectively. Among unsedated preterm infants, between‐test reproducibility over a 3‐day interval was similar to within‐test repeatability. The wide limits of agreement may limit the application of these measures to detect a clinically significant change in condition in small preterm infants. Pediatr Pulmonol. 2010; 45:62–70. © 2009 Wiley‐Liss, Inc.  相似文献   
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BACKGROUND: Cows' milk sensitive reflux oesophagitis is an emerging clinical entity in children, normally indistinguishable from primary gastro-oesophageal reflux (GOR) apart from the response to dietary antigen exclusion. It is conjectural whether a tendency towards mucosal eosinophilia distinguishes this group from primary GOR. AIMS: To determine whether there may be differences in the mucosal lesion within the oesophagus in those children with reflux in association with cows' milk induced small bowel pathology, particularly in relation to the eosinophil chemokine eotaxin. METHODS: A total of 29 children underwent endoscopic assessment, including nine with cows' milk sensitive enteropathy (CMSE) and associated GOR, seven histologically normal controls, six with primary GOR, and seven disease controls. Oesophageal biopsy specimens were examined immunohistochemically for the chemokines eotaxin and MCP-2, and T cell lineage and activation markers. RESULTS: Strong upregulation of eotaxin expression, limited to basal and papillary epithelium, occurred in all CMSE patients. By contrast, weak expression was seen in a minority of controls and in 50% of primary GOR patients. Infiltration of CD3, CD4, and CD8 lymphocytes occurred in similar distribution in CMSE patients, significantly increased above controls. Significant upregulation of activation markers (CD25, HLA-DR) was also seen in the CMSE group within basal and papillary epithelium compared to controls and primary GOR. CONCLUSION: Basal and papillary epithelial eotaxin expression, with focal lymphocyte activation, was seen in infants with CMSE associated GOR. This preliminary study provides early evidence to suggest a pathogenesis distinct from primary GOR, in which specific recruitment of T cells and eosinophils may contribute to oesophageal dysmotility.  相似文献   
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During bacterial cannibalism, a differentiated subpopulation harvests nutrients from their genetically identical siblings to allow continued growth in nutrient-limited conditions. Hypothesis-driven imaging mass spectrometry (IMS) was used to identify metabolites active in a Bacillus subtilis cannibalism system in which sporulating cells lyse nonsporulating siblings. Two candidate molecules with sequences matching the products of skfA and sdpC, genes for the proposed cannibalistic factors sporulation killing factor (SKF) and sporulation delaying protein (SDP), respectively, were identified and the structures of the final products elucidated. SKF is a cyclic 26-amino acid (aa) peptide that is posttranslationally modified with one disulfide and one cysteine thioether bridged to the α-position of a methionine, a posttranslational modification not previously described in biology. SDP is a 42-residue peptide with one disulfide bridge. In spot test assays on solid medium, overproduced SKF and SDP enact a cannibalistic killing effect with SDP having higher potency. However, only purified SDP affected B. subtilis cells in liquid media in fluorescence microscopy and growth assays. Specifically, SDP treatment delayed growth in a concentration-dependent manner, caused increases in cell permeability, and ultimately caused cell lysis accompanied by the production of membrane tubules and spheres. Similarly, SDP but not SKF was able to inhibit the growth of the pathogens Staphylococcus aureus and Staphylococcus epidermidis with comparable IC50 to vancomycin. This investigation, with the identification of SKF and SDP structures, highlights the strength of IMS in investigations of metabolic exchange of microbial colonies and also demonstrates IMS as a promising approach to discover novel biologically active molecules.  相似文献   
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