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81.
ObjectivesThis study characterized the determinants of carotid intima-media thickness (cIMT) in a large (n > 4,000) longitudinal cohort of healthy young people age 9 to 21 years.BackgroundGreater cIMT is commonly used in the young as a marker of subclinical atherosclerosis, but its evolution at this age is still poorly understood.MethodsAssociations between cardiovascular risk factors and cIMT were investigated in both longitudinal (ages 9 to 17 years) and cross-sectional (ages 17 and 21 years) analyses, with the latter also related to other measures of carotid structure and stress. Additional use of ultra-high frequency ultrasound in the radial artery at age 21 years allowed investigation of the distinct layers (i.e., intima or media) that may underlie observed differences.ResultsFat-free mass (FFM) and systolic blood pressure were the only modifiable risk factors positively associated with cIMT (e.g., mean difference in cIMT per 1-SD increase in FFM at age 17: 0.007 mm: 95% confidence interval [CI]: 0.004 to 0.010; p < 0.001), whereas fat mass was negatively associated with cIMT (difference: ?0.0032; 95% CI: 0.004 to ?0.001; p = 0.001). Similar results were obtained when investigating cumulative exposure to these factors throughout adolescence. An increase in cIMT maintained circumferential wall stress in the face of increased mean arterial pressure when increases in body mass were attributable to increased FFM, but not fat mass. Risk factor?associated differences in the radial artery occurred in the media alone, and there was little evidence of a relationship between intimal thickness and any risk factor.ConclusionsSubtle changes in cIMT in the young may predominantly involve the media and represent physiological adaptations as opposed to subclinical atherosclerosis. Other vascular measures may be more appropriate for the identification of arterial disease before adulthood.  相似文献   
82.
Electronic medical records (EMRs) and electronic health records (EHRs) have become essential systems by which nurse practitioners (NPs) communicate vital patient information to other members of the health care team as well as to patients. In this article we examine the important distinctions between EMRs and EHRs; review the genesis of these types of records; summarize applicable provisions of the Health Insurance Portability and Accountability Act from a recent legal case centered around NP utilization of EMRs and EHRs; address open patient access to medical information; and examine threats to security. Suggestions are offered on ways in which NPs can safeguard confidential patient information.  相似文献   
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Hypertension is almost universal in end‐stage renal disease (ESRD) and contributes to the substantial cardiovascular (CV) morbidity and mortality observed in these patients. The management of blood pressure (BP) in ESRD is complicated by a number of factors, including missed dialysis treatments, intradialytic changes in BP, medication removal with dialysis, and poor correlation of BPs obtained in the dialysis unit with those at home and with CV outcomes. Control of extracellular volume with ultrafiltration and dietary sodium restriction represents the principal strategy to manage hypertension in ESRD, and antihypertensive medications are subsequently added if this strategy is inadequate. While reduction in BP with medication improves CV outcomes, few head‐to‐head clinical trials have been performed to firmly establish the superiority of one antihypertensive medication class over another. Therefore, individualization of therapy is necessary, and patient comorbidities must be considered. Angiotensin‐converting enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs), and beta‐blockers are reasonable first‐line agents for most patients. ACE inhibitors and ARBs exert cardioprotective effects that are independent of BP reduction. Medications that are removed with dialysis may be preferred in patients who are prone to develop intradialytic hypotension. Intradialytic hypertension can be managed with challenging the patient's dry weight and using nondialyzable medications. Within a class of antihypertensive medications, there may be large variability in drug removal with dialysis, which must be considered upon medication selection. Studies demonstrate that even thrice‐weekly dosing of medication after dialysis has robust BP‐lowering effects, which may be a useful regimen in nonadherent patients.  相似文献   
85.
Plankeel JF  McMullen B  MacIntyre NR 《Chest》2005,127(1):110-116
STUDY OBJECTIVES: Pulmonary rehabilitation (PR) that includes exercise training can improve exercise tolerance and quality of life for patients with COPD. However, the degree of benefit from PR is variable. We hypothesized that the exercise response to PR varies depending on the initial factors that limit exercise. DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS: We retrospectively analyzed the change in exercise capacity after PR in 290 nonhypoxemic patients with COPD. We classified patients into the following subgroups based on the primary limitation seen on initial exercise testing: (1) ventilatory-limited (VL); (2) cardiovascular-limited (CVL); (3) mixed ventilatory/cardiovascular-limited (VLCVL); and (4) non-cardiopulmonary-limited (NL). We compared outcomes among subgroups. RESULTS: In the entire study population, PR led to increased timed walk distance (30.3%; p < 0.0001) and maximal oxygen consumption (VO2max) [84.8 mL/min; p < 0.0001]. Stepwise multiple regression selected age, ventilatory reserve at peak exercise, and exercise arterial oxygen pressure as individual predictors of improvement in VO2max. VO2max increased in the VL subgroup (30.4 mL/min; p = 0.008), the CVL subgroup (109.0 mL/min; p < 0.0001), the mixed VLCVL subgroup (61.3 mL/min; p < 0.0001), and NL subgroups (110.5 L/min; p < 0.0001). The improvement in VO2max was greater in the CVL subgroup than in the VL subgroup (p < 0.0001). Timed walk distance improved to a similar degree in all subgroups (26 to 36%). CONCLUSIONS: Patients with nonventilatory exercise limitations experience the greatest increase in VO2max after PR. However, even patients with severe ventilatory limitation can improve exercise tolerance with PR.  相似文献   
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87.
Optimization of illumination and detection optics is pivotal for multiphoton imaging in highly scattering tissue and the objective lens is the central component in both of these pathways. To better understand how basic lens parameters (NA, magnification, field number) affect fluorescence collection and image quality, a two-detector setup was used with a specialized sample cell to separate measurement of total excitation from epifluorescence collection. Our data corroborate earlier findings that low-mag lenses can be superior at collecting scattered photons, and we compare a set of commonly used multiphoton objective lenses in terms of their ability to collect scattered fluorescence, providing guidance for the design of multiphoton imaging systems. For example, our measurements of epi-fluorescence beam divergence in the presence of scattering reveal minimal beam broadening, indicating that often-advocated over-sized collection optics are not as advantageous as previously thought. These experiments also provide a framework for choosing objective lenses for multiphoton imaging by relating the results of our measurements to various design parameters of the objectives lenses used.OCIS codes: (110.0113) Imaging through turbid media, (180.2520) Fluorescence microscopy, (180.4315) Nonlinear microscopy, (180.6900) Three-dimensional microscopy  相似文献   
88.

Objectives

The conference objectives included educating patients and advocates about clinical trials, educating the clinical research community about patient perspectives on participating in clinical trial design, and identifying strategies to increase participation in clinical trial design for neurological disorders.

Design

Observations were noted during a 1‐day conference attended by patients, patient advocates, clinical trial staff, and investigators. The conference offered didactic sessions, small, and large group discussions.

Participants

Conference participants were patients, patient advocates, clinical trial staff, students, and investigators interested in engaging patients in clinical trial design for neurological disorders.

Measures

Conference participants were asked to consider lessons learned that could increase patient engagement in clinical trial design.

Results

We found that there is growing interest in including patients in the design of clinical trials for neurological disorders. Several themes emerged on how to move forward: networking; the multifaceted roles of advocates in research; training and education; creating patient–researcher partnerships; and clinical trials regulation issues.

Conclusions

The conference provided a forum for dialogue regarding stakeholder engagement in the design of clinical trials for neurological disorders. This experience provides a template for replication and dissemination of this conference and informs next steps to accelerate the pathway from dialogue to action.  相似文献   
89.
BackgroundThe Ponseti method is the preferred treatment for idiopathic clubfoot. Although popularised by orthopaedic surgeons it has expanded to physiotherapists and other health practitioners. This study reviews the results of a physiotherapist-led Ponseti service for idiopathic and non-idiopathic clubfeet and compares these results with those reported by other groups.MethodA prospective cohort of clubfeet (2005–2012) with a minimum 2-year follow-up after correction was reviewed. Physiotherapists treated 91 children—41 patients (69 feet) had non-idiopathic deformities and 50 children (77 feet) were idiopathic. Objective outcomes were evaluated and compared to results from other groups managing similar patient cohorts.ResultsThe mean follow-up was 4.6 years (range 2–8.3 years) for both groups. The non-idiopathic group required a median of 7 casts to correct the clubfoot deformity with an 83 % tenotomy rate compared to a median of 5 casts for the idiopathic group with a 63 % tenotomy rate. Initial correction was achieved in 96 % of non-idiopathic feet and in 100 % of idiopathic feet. Recurrence requiring additional treatment was higher in the non-idiopathic group with 40 % of patients (36 % of feet) sustaining a relapse as opposed to 8 % (6 % feet) in the idiopathic group. Surgery was required in 26 % of relapsed non-idiopathic feet and 6 % of idiopathic.ConclusionsAlthough Ponseti treatment was not as successful in non-idiopathic feet as in idiopathic feet, deformity correction was achieved and maintained in the mid-term for the majority of feet. These results compare favourably to other specialist orthopaedic-based services for Ponseti management of non-idiopathic clubfeet.

Level of evidence

Prognostic Level III.  相似文献   
90.
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