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This study compared macro‐ and microvascular endothelial function and redox status in active vs inactive HIV‐infected patients (HIVP) under antiretroviral therapy. Using a cross‐sectional design, macro‐ and microvascular reactivity, systemic microvascular density, and oxidative stress were compared between 19 HIVP (53.1 ± 6.1 year) enrolled in a multimodal training program (aerobic, strength and flexibility exercises) for at least 12 months (60‐minutes sessions performed 3 times/wk with moderate intensity) vs 25 sedentary HIVP (51.2 ± 6.3 year). Forearm blood flow during reactive hyperemia (521.7 ± 241.9 vs 361.4% ± 125.0%; P = 0.04) and systemic microvascular density (120.8 ± 21.1 vs 105.6 ± 25.0 capillaries/mm2; P = 0.03) was greater in active than inactive patients. No significant difference between groups was detected for endothelium‐dependent and independent skin microvascular vasodilation (P > 0.05). As for redox status, carbonyl groups (P = 0.22), lipid peroxidation (P = 0.86), catalase activity (P = 0.99), and nitric oxide levels (P = 0.72) were similar across groups. However, superoxide dismutase activity was greater in active vs inactive HIVP (0.118 ± 0.013 vs 0.111 ± 0.007 U/mL; P = 0.05). Immune function reflected by total T CD4 and T CD8 counts (cell/mm3) did not differ between active and inactive groups (P > 0.82). In conclusion, physically active HIVP exhibited similar immune function, but greater macrovascular reactivity, systemic microvascular density, and superoxide dismutase activity than inactive patients of similar age.  相似文献   
75.
RATIONALE: The aim of the present study was to assess, intraindividually, the relationship among slow eye movements, electroencephalogram (EEG) power, and subjective measures of sleepiness during a 40-hour sleep deprivation comparing 2 experimental conditions: eyes-open and eyes-closed. METHODS: Nineteen normal subjects participated in a sleep-deprivation protocol with recordings of the waking Cz-A1-2 EEG in 36 sessions at 1-hour intervals starting at 10:00 AM. Each session consisted of a 2-minute eyes-closed period, followed by a 4-minute eyes-open period. Electrooculogram, self-ratings (Karolinska Sleepiness Scale and Visual Analog Scale for Global Vigor), and tympanic temperature were also recorded. RESULTS: Changes in sleepiness and alertness are paralleled by increases in slow eye movements and theta and delta EEG power. The beginning of the rise of delta, theta, and slow eye movement activity corresponded to the nadir of temperature, peaking at 7:00AM. Cross-correlational analyses showed that changes in slow eye movements were strictly phase locked to those in slow-frequency EEG bands and in subjective measures. The comparison of time intervals that were equivalent with respect to circadian phase confirms the effects of the increased sleepiness on slow eye movement activity and on the other measures. The temporal concordance of the different physiologic and subjective measures is also reflected in the individual time courses. Individual and group analyses converged in indicating that slow eye movements can be considered reliable indexes of sleepiness but only in the eyes-closed condition. CONCLUSIONS: Results suggest that subjective and EEG changes associated with higher sleepiness are paralleled by an increase in slow eye movement activity, but this relationship exists almost exclusively with the eyes closed. Hence, its use in practical and operational contexts seems limited.  相似文献   
76.

Objectives

Translate, cross-culturally adapt and validate the Rapid Geriatric Assessment (RGA) for Brazilian community-dwelling adults.

Design

Cross-sectional study, using a quantitative approach.

Setting

Urban population from the city of São Carlos, located in the interior of São Paulo State, Brazil. Participants: 148 individuals aged 60 or over.

Measurements

Participants were assessed using the RGA, Fried Frailty Phenotype, International Physical Activity Questionnaire - long version, Addenbrooke´s Cognitive Exam - Revised Version, Mini Nutritional Assessment, short Form - 36, EuroQol 5-Dimension, Geriatric Depression Scale - short version, in addition to performing Dual Energy X-ray Absorptiometry to diagnose sarcopenia, according to the criteria established by the European Working Group on Sarcopenia in Older People.

Results

In the translation and adaption process of the RGA, steps recommended by the literature were followed: initial translation, synthesis of translations, backward translation, evaluation from the panel of judges, and pre-test. When evaluating the psychometric properties of the scale, satisfactory reliability (internal consistency and stability) and validity (content, concurrent criterion and convergent, divergent and discriminant construct) were verified.

Conclusion

The Brazilian version of the RGA is reliable and valid, and can be used in the Brazilian context to evaluate the elderly population.
  相似文献   
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Objective:

The efficiency of rotary, manual and ultrasonic root canal instrumentation techniques was investigated in proximally flattened root canals.

Material and Methods:

Forty human mandibular left and right central incisors, lateral incisors and premolars were used. The pulp tissue was removed and the root canals were filled with red die. Teeth were instrumented using three techniques: (i) K3 and ProTaper rotary systems; (ii) ultrasonic crown-down technique; and (iii) progressive manual technique. Roots were bisected longitudinally in a buccolingual direction. The instrumented canal walls were digitally captured and the images obtained were analyzed using the Sigma Scan software. Canal walls were evaluated for total canal wall area versus noninstrumented area on which dye remained.

Results:

No statistically significant difference was found between the instrumentation techniques studied (p<0.05).

Conclusion:

The findings of this study showed that no instrumentation technique was 100% efficient to remove the dye.  相似文献   
80.
Lasers in Medical Science - Photobiomodulation therapy (PBM) is often used to treat musculoskeletal disorders such as chronic non-specific low back pain (NSCLBP) as it can have positive effects on...  相似文献   
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