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91.

Objective

To assess the feasibility of measuring ventilatory threshold (VT) in higher-level motor-complete spinal cord injury (SCI) using 4 different analysis methods based on noninvasive gas exchange.

Design

Observational.

Setting

Laboratory testing.

Participants

Individuals with C4-T6 motor-complete SCI (16 paraplegia, 22 tetraplegia; American Spinal Injury Association Impairment Scale A/B; 42±10 years old).

Interventions

Not applicable.

Main Outcome

VT from a graded arm cycling test to volitional exhaustion using 4 methods: ventilatory equivalents, excess CO2, V-slope, and combined method.

Results

VT could be identified in all individuals with paraplegia, but in only 68% of individuals with tetraplegia. Individuals without observable VT completed the graded exercise test with lower ventilatory rate, peak power output, and peak oxygen consumption (Vo2peak) (all P<.05), compared to those with a detectable VT. Bland-Altman plots indicate minimal bias between methods (range: 0.01-0.03 L/min), with 95% limits of agreement of the difference within 0.25 L/min. Absolute V.o2 at VT with individual methods were all correlated to peak power output (r>0.74; P<.01) and Vo2peak (r>0.91; P<.01), with negligible differences between methods.

Conclusions

The assessment of VT is a feasible alternative to peak exercise testing for aerobic fitness in individuals with higher-level, motor-complete SCI, although care should be taken when interpreting VT in individuals with tetraplegia who have lower cardiorespiratory fitness and lower peak power outputs.  相似文献   
92.

Purpose

The relation between driving pressure (plateau pressure-positive end-expiratory pressure) and mortality has never been studied in obese ARDS patients. The main objective of this study was to evaluate the relationship between 90-day mortality and driving pressure in an ARDS population ventilated in the intensive care unit (ICU) according to obesity status.

Methods

We conducted a retrospective single-center study of prospectively collected data of all ARDS patients admitted consecutively to a mixed medical-surgical adult ICU from January 2009 to May 2017. Plateau pressure, compliance of the respiratory system (Crs) and driving pressure of the respiratory system within 24 h of ARDS diagnosis were compared between survivors and non-survivors at day 90 and between obese (body mass index?≥?30 kg/m2) and non-obese patients. Cox proportional hazard modeling was used for mortality at day 90.

Results

Three hundred sixty-two ARDS patients were included, 262 (72%) non-obese and 100 (28%) obese patients. Mortality rate at day 90 was respectively 47% (95% CI, 40–53) in the non-obese and 46% (95% CI, 36–56) in the obese patients. Driving pressure at day 1 in the non-obese patients was significantly lower in survivors at day 90 (11.9?±?4.2 cmH2O) than in non-survivors (15.2?±?5.2 cmH2O, p?<?0.001). Contrarily, in obese patients, driving pressure at day 1 was not significantly different between survivors (13.7?±?4.5 cmH2O) and non-survivors (13.2?±?5.1 cmH2O, p?=?0.41) at day 90. After three multivariate Cox analyses, plateau pressure [HR?=?1.04 (95% CI 1.01–1.07) for each point of increase], Crs [HR?=?0.97 (95% CI 0.96–0.99) for each point of increase] and driving pressure [HR?=?1.07 (95% CI 1.04–1.10) for each point of increase], respectively, were independently associated with 90-day mortality in non-obese patients, but not in obese patients.

Conclusions

Contrary to non-obese ARDS patients, driving pressure was not associated with mortality in obese ARDS patients.
  相似文献   
93.
94.
The literature on the effects of public smoking bans on smoking behaviour presents conflicting results and there is limited evidence on their impact on active smoking. This paper evaluates the impact of smoking bans on active smoking using data from the British Household Panel Survey and exploiting the policy experiment provided by the differential timing of the introduction of the bans in Scotland and England. We assess the short‐term impact of the smoking bans by employing a series of flexible difference‐in‐differences fixed effects panel data models. We find that the introduction of the public smoking bans in England and Scotland had limited short‐run effects on both smoking prevalence and the total level of smoking. Although we identify significant differences in trends in smoking consumption across the survey period by population sub‐groups, we find insufficient evidence to conclude that these were affected by the introduction of the smoking bans. These results challenge those found in the public health literature but are in line with the most recent strand of economic literature indicating that there is no firm evidence on the effects of smoking bans on smoking. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
95.
96.
97.
AIDS and Behavior - We previously demonstrated that village community mobilization (CM) was associated with reduced HIV incidence among adolescent girls and young women (AGYW) in South Africa....  相似文献   
98.
AIDS and Behavior - We aimed to measure social protection coverage among the general population, women and men living with HIV (WLHIV, MLHV), female and male sex workers (FSW, MSW), men who have...  相似文献   
99.
AIDS and Behavior - Adolescents and young adults (AYA; 13–24&nbsp;years-old) comprise 22% of new HIV infections in the United States (US), most of whom live in the South. We used the...  相似文献   
100.
AIDS and Behavior - Transactional sex increases HIV risk among adolescent girls and young women (AGYW). Understanding the individual and dyadic nature of transactional sex may provide evidence for...  相似文献   
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