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1.
Concealed soft body armor inhibits convective and evaporative heat loss and increases heat storage, especially in hot environments. One option to potentially mitigate heat storage is to promote airflow under the soft body armor. The purpose of this study was to evaluate the effect of ambient air induction (~100 liters per minute) on heat strain while wearing concealed soft body armor in a hot environment (wet bulb globe temperature = 30°C). A counter-balanced, repeated measures protocol was performed with nine healthy male volunteers. Participants were fitted with either a traditional or modified Level II concealed soft body armor. Participants performed cycles of 12 min of walking (1.25 liters per minute) and 3 min of arm curls (0.6 liters per minute) for a total of 60 min. Two-way repeated measures ANOVA was used to assess the mean differences in physiological measures (rectal temperature, heart rate, micro-environment [temperature and relative humidity]). Post hoc Bonferroni analysis and paired samples t-tests (alpha = 0.01) were conducted on omnibus significant findings. Perceptual measures (perceived exertion, thermal comfort) were analyzed using Wilcoxon Signed Ranks Tests. Modification led to an improvement in perceived exertion at 45 min (MOD: 10 ± 1; CON: 11 ± 2; p ≤ 0.001) and 60 min (MOD: 10 ± 2; CON: 12 ± 2; p ≤ 0.001) and a reduction in micro-environment temperature in MOD (1.0 ± 0.2°C, p = 0.03) compared to CON. Modification did not attenuate change in rectal temperature or heart rate (p < 0.01) during 60-min work bout. Change in rectal temperature approached significance between MOD and CON at the end of the work bout (MOD: 0.4 ± 0.2°C; CON: 0.7 ± 0.3°C; p = 0.048). The slope of rectal temperature was significantly greater (p = 0.04) under CON compared to MOD. These data suggest that air induction may provide small benefits while wearing concealed soft body armor, though improvements are needed to lessen physiological strain.  相似文献   

2.

Background

The number of older adults residing in assisted living communities is increasing. Despite the benefits of physical activity (PA) on physical and cognitive capacities, and the opportunities for being active offered in these living environments, this population is highly sedentary and more at risk of physical decline. This study aimed to assess the feasibility, the acceptability, and the effects of PA intervention using gerontechnology in assisted living communities.

Methods

Forty-two older adults in 4 assisted living communities were recruited and randomly assigned to an exercise intervention group (EX) or a control group (CON) using a 2:1 ratio. The EX group followed a 12-week PA program (2 sessions per week) using gerontechnology. Body composition, health status, quality of life, and functional capacities were evaluated at baseline, 12 weeks, and 24 weeks after baseline.

Results

Differences between groups were observed in the number of reported comorbidities (EX: 3.1 ± 1.6 vs CON: 5.0 ± 1.8; P = .007), SF-36 total score (EX: 80% ± 10% vs CON: 66% ± 15%; P = .004), and Short Physical Performance Battery (SPPB) total score (EX: 9.1 ± 1.8 vs CON: 7.5 ± 1.4; P = .006) at baseline. The EX group completed 89% ± 17% of the 24 prescribed sessions and realized 67% ± 13% of them in autonomy, reaching a quality level of 87% ± 6%. Of the EX participants, 93.8% enjoyed the exercises a lot or well, and 92.8% of them rated the exercises as being either easy or a little difficult. Changes between baseline and follow-up were statistically different between groups for walking speed (EX: +0.10 ± 0.20 vs CON: ?0.04 ± 0.16 m/s; P = .04) and the SPPB score (EX: +1.1 ± 2.0 vs CON: ?0.4 ± 1.6; P = .03).

Conclusion

We found that PA intervention using gerontechnology in assisted living communities for older adults was feasible and acceptable, but more importantly induced improvement in functional capacities and walking speed, which is the main predictor of mortality in the elderly population.  相似文献   

3.
Background: There is a lack of quantification of occupational physical activity (OPA) and leisure time physical activity (LTPA) among construction workers.

Objectives: To describe physical activity energy expenditure (PAEE), physical workload, and the effect of a PA-intervention among construction workers.

Methods: Sixty-seven Construction workers self-reported their physical activity (PA), had PA assessed directly (PAEE), and observed OPA using the tool “Posture, Activity, Tools and Handling.” The PA-intervention (Intervention; n = 29, Controls; n = 24) included 3x20-min training/week for 12 weeks.

Results: Baseline median OPA was 5036 MET-min/week and LTPA 2842 MET-min/week, p < 0.01. OPA directly recorded was (mean ± SE): 56.6 ± 3.2 J/kg/min and LTPA was: 35.7 ± 2.2 J/kg/min (p < 0.001). Manual material handling was performed for ≥ 25% of working time by more than 50% of the participants. Post-intervention, the training group reduced overall PAEE compared to the control group but not specifically during work.

Conclusions: OPA was within the maximum recommended level of 1/3 proposed in consensus guidelines but did not decrease with PA-intervention.  相似文献   

4.
A major concern for responders to hazardous materials (HazMat) incidents is the heat strain that is caused by fully encapsulated impermeable chemical protective suits. In a research project, funded by the US Department of Defense, the thermal strain experienced when wearing these suits was studied. One particular area of interest was the fluid loss of responders during work in these suits as dehydration may be an additional health concern to the heat strain. 17 City of Raleigh firemen and 24 students were tested at two different labs. Subjects between the ages of 25 and 51 were used for human subject trials in a protocol approved by the local ethical committee. Six different Level A HazMat suits were evaluated in three climates: moderate (24°C, 50% RH, 20°C WBGT), warm-wet (32°C, 60% RH, 30°C WBGT), and hot-dry (45°C, 20% RH, 37°C WBGT, 200 W/m2 radiant load) and at three walking speeds: 2.5 km/hr, 4 km/hr, and 5.5 km/hr. 4 km/hr was tested in all three climates and the other two walking speeds were tested in the moderate climate. Weight loss data was collected to determine fluid loss during these experiments. Working time ranged from as low as 20 min in the hot-dry condition to 60 min (the maximum) in the moderate climate, especially common at the lowest walking speed. The overall results from all experiments showed that fluid loss ranged from 0.2–2.2 L during these exposures, with the average fluid loss being 0.8 L, with 56% of the data between 0.5 L and 1 L of fluid loss. Further analysis showed that a suggestion of drinking 0.7 Liter per hour would safely hydrate over 50% of responders after one work-rest cycle. Applying this fluid volume over three work-rest cycles only put 11% of responders at risk of hypohydration vs. the 57% at risk with no fluid intake.  相似文献   

5.
The ACGIH® Threshold Limit Value® (TLV®) is used to limit heat stress exposures so that most workers can maintain thermal equilibrium. That is, the TLV was set to an upper limit of Sustainable exposures for most people. This article addresses the ability of the TLV to differentiate between Sustainable and Unsustainable heat exposures for four clothing ensembles over a range of environmental factors and metabolic rates (M). The four clothing ensembles (woven clothing, and particle barrier, water barrier and vapor barrier coveralls) represented a wide range of evaporative resistances. Two progressive heat stress studies provided data on 480 trials with 1440 pairs of Sustainable and Unsustainable exposures for the clothing over three levels of relative humidity (rh) (20, 50 and 70%), three levels of metabolic rate (115, 180, and 254 Wm?2) using 29 participants. The exposure metric was the difference between the observed wet bulb globe temperature (WBGT) and the TLV. Risk was characterized by odds ratios (ORs), Receiver Operating Characteristic (ROC) curves, and dose-response curves for the four ensembles. Conditional logistic regression models provided information on ORs. Logistic regressions were used to determine ROC curves with area under the curve (AUC), model the dose-response curve, and estimate offsets from woven clothing. The ORs were about 2.5 per 1°C-WBGT for woven clothing, particle barrier, and water barrier and for vapor barrier at 50% rh. When using the published Clothing Adjustment Values (CAVs, also known as Clothing Adjustment Factors, CAFs) or the offsets that included different values for vapor barrier based on rh, the AUC for all clothing was 0.86. When the fixed CAVs of the TLV were used, the AUC was 0.81. In conclusion, (1) ORs and the shapes of the dose-response curves for the nonwoven coveralls were similar to woven clothing, and (2) CAVs provided a robust way to account for the risk of nonwoven clothing. The robust nature of CAV extended to the exclusion of different adjustments for vapor barrier by rh.  相似文献   

6.
Objective: The aim of this research was to determine the relationship among protein (PRO) intake, body composition, and muscle strength in overweight and obese firefighters. A secondary objective was to evaluate differences in body composition and muscle strength among overweight and obese firefighters with low (L; < 0.8 g·kg?1), moderate (M; 0.8–1.0 g·kg?1), and high (H; > 1.0 g·kg?1) PRO intake.

Methods: Relative PRO intake [r_PRO] was evaluated from 3-day dietary logs, self-reported by 43 overweight and obese male career firefighters (mean ± standard deviation; age = 37.3 ± 7.2 years; body mass index = 33.2 ± 5.0 kg·m?2; percent body fat [%BF] = 28.9 ± 4.0%). Body composition (fat mass [FM], %BF, lean mass [LM], percent LM [%LM]) and muscle strength (peak torque [PT], relative peak torque [r_PT] of the leg extensors) were measured using dual-energy x-ray absorptiometry and isokinetic dynamometry, respectively.

Results: Greater r_PRO was associated with less FM, %BF, LM (r = ?0.498 to ?0.363) and greater %LM (r = 0.363), but not muscle strength (p > 0.05). Fat mass (r = ?0.373) and %BF (r = ?0.369) were associated with lower r_PT; %LM was associated with greater r_PT (r = 0.373). Individuals with L r_PRO had greater FM (mean difference ± standard error: L–H = 10.08 ± 3.18 kg), %BF (L–H = 3.8% ± 1.4%) and lower %LM (L–H = ?3.7% ± 1.3%) than those with H r_PRO (p < 0.05) but no significant differences in muscle strength (p > 0.05).

Conclusions: Protein intake > 0.8 g·kg?1 was associated with more favorable body composition in male career firefighters.  相似文献   

7.
This study investigated the effects of environmental temperature on repetitive box lifting (RBL) performance, associated stress hormone and creatine kinase (CK) responses. Ten healthy males performed two experimental trials in a random crossover design. The trials consisted of three 40 min (10 min sitting, 20 min standing, and 10 min RBL) circuits performed in either 23°C or 38°C followed by a 180 min seated recovery period in 23°C. RBL performance (i.e., number of boxes lifted) was reduced (p ≤ 0.05) in 38°C compared to the 23°C trial. Physiological Strain Index was significantly different between trials (38°C: 8.5 ± 1.1 versus 23°C: 7.2 ± 0.7; p ≤ 0.01). Plasma testosterone was elevated (p ≤ 0.05) across both trials and then decreased at 60 min recovery, compared to pre-exercise (PRE) measures, but was higher (p ≤ 0.05) during the 38°C trial. Plasma cortisol increased (p ≤ 0.05) at 60 min during both trials and remained elevated until 120 min in 23°C, and until 60 min recovery in 38°C. Serum CK was greater through 48 hr post compared to PRE values in both trials. Thus, 10 min RBL performance was reduced in 38°C despite the 30-min rest periods between RBL intervals. Plasma testosterone and cortisol were generally higher during the 38°C trial, suggesting a greater stress response. Additional research is needed to determine optimal work:rest cycles for maximizing work performance in thermally oppressive environments.  相似文献   

8.
We examined heat balance using an American Conference of Governmental Industrial Hygienists threshold limit value allocated exercise protocol in hot-dry (HD; 46 °C, 10% relative humidity (RH)) and warm-wet (WW; 33 °C, 60% RH) environments of equivalent WBGT (29 °C) for different clothing ensembles. Whole-body heat exchange and changes in body heat content (ΔH(b)) were measured using simultaneous direct whole-body and indirect calorimetry. Eight males performed six 15-min cycling periods at a constant rate of metabolic heat production (360 W) interspersed by 5-min rest periods for six experimental trials: HD and WW environments for a seminude control (CON), modified work uniform (MWU, moisture permeable top and work pants), and standard work uniform (SWU, work coveralls and cotton undergarments). Whole-body evaporative and dry heat exchange, rectal temperature (T(re)), and heart rate were measured continuously. The cumulative ΔH(b) during the 2 h intermittent exercise protocol was similar between HD and WW environments for each of the clothing ensembles (CON, 387 ± 55 vs. 435 ± 49 kJ; MWU, 485 ± 58 vs. 531 ± 61 kJ; SWU, 585 ± 74 vs. 660 ± 54 kJ, respectively). Similarly, no differences in T(re) (CON, 37.67 ± 0.07 vs. 37.48 ± 0.08 °C; MWU, 37.73 ± 0.08 vs. 37.53 ± 0.09 °C; SWU, 38.01 ± 0.09 vs. 37.94 ± 0.05 °C) or heat rate (CON, 93 ± 3 vs. 84 ± 3 beats·min?1; MWU, 102 ± 5 vs. 95 ± 9 beats·min?1; SWU, 119 ± 8 vs. 110 ± 9 beats·min?1) were observed at the end of the 2 h intermittent exercise protocol in HD vs. WW environments, respectively. We showed similar levels of thermal and cardiovascular strain for intermittent work performed in high heat stress conditions of varying environmental conditions but similar WBGT.  相似文献   

9.

Background

Excess mortality from cardiovascular disease during cold seasons is a worldwide issue. Although some physiologic studies suggests that platelet activation via cold exposure may cause an increased incidence of cardiovascular disease in winter, the influence of indoor cold exposure in real-life situations on platelet (PLT) count remains unclear.

Methods

A cross-sectional study was conducted among 1095 elderly individuals. After obtaining a venous sample in the morning, indoor temperature of participants' home was measured every 10 min for 48 h. The mean indoor temperature while the participants stayed at home was calculated. All measurement was conducted during cold seasons (October to April) from 2010 to 2014.

Results

The mean age of the 1095 participants was 71.9 years. They spent 87.3% of the day at home (20 h 27 min). A 1 °C lower daytime indoor temperature was associated with a significant increase in PLT count of 1.47 × 109/L (95% confidence interval, 0.39–2.56 × 109/L). Compared with the warmest tertile group (20.1 [standard deviation {SD}, 0.09] °C), the coldest group (11.7 [SD, 0.12] °C) showed a 5.2% higher PLT count (238.84 [SD, 3.30] vs. 226.48 [SD, 3.32] × 109/L; P = 0.01), even after adjusting for basic characteristics (age, gender, body weight, and smoking), antihypertensive medication, comorbidities (diabetes, estimated glomerular filtration rate), socioeconomic status (household income and education), day length, and outdoor temperature.

Conclusions

We found a significant and independent association between lower indoor temperature and higher PLT count among elderly in winter.  相似文献   

10.
Purpose: In this article, we evaluated physiological strain in electrical utilities workers during consecutive work shifts in hot outdoor conditions.

Methods: Four highly experienced electrical utilities workers were monitored during regularly scheduled work performed in hot conditions (~34°C) on two consecutive days. Worker hydration (urine specific gravity) was assessed prior to and following work. The level of physical exertion was determined by video analysis. Body core temperature (Tcore) and heart rate (HR; presented as a percentage of maximum, %HRmax) were monitored continuously. Responses were reported for each worker individually and as a group mean ± standard deviation.

Results: According to current guidelines, all workers were dehydrated prior to work on both days (urine specific gravity: day 1, 1.025 ± 0.005; day 2, 1.029 ± 0.004) and remained dehydrated following work (urine specific gravity: day 1, 1.027 ± 0.015; day 2, 1.032 ± 0.004) except for one worker on day 1 (urine specific gravity of 1.005). On day 1, the proportion of the work shift spent at rest (as defined by the American Conference for Governmental and Industrial Hygienists, ACGIH) was 51 ± 15% (range: 30–64%). Time spent resting increased in all workers on the second day reaching 66 ± 5% (range: 60–71%) of the work shift. Work shift average Tcore was 37.6 ± 0.1°C (range: 37.5–37.7°C) and 37.7 ± 0.2°C (range: 37.5–37.9°C) on days 1 and 2, respectively. Peak Tcore surpassed the ACGIH recommended threshold limit of 38.0°C for work in the heat in three workers on day 1 (38.1 ± 0.2°C, range: 37.8–38.2°C) while all workers exceeded this threshold on day 2 (38.4 ± 0.2°C, range: 38.2–38.7°C). By contrast, work shift average (day 1, 67 ± 7%HRmax, range: 59–74%HRmax; day 2, 65 ± 4%HRmax, range: 60–70%HRmax) and peak (day 1, 90 ± 6%HRmax, range: 83–98%HRmax; day 2, 87 ± 10%HRmax, range: 73–97%HRmax) HR were similar between days.

Conclusion: This case report demonstrates elevations in thermal strain over consecutive work shifts despite decreases in work effort in electrical utilities workers during regular work in the heat.  相似文献   


11.
Background

Dirofilaria immitis is a worldwide parasite that is endemic in many parts of the United States. There are many commercial assays available for the detection of D. immitis antigen, one of which was modified and has reentered the market. Our objective was to compare the recently reintroduced Witness® Heartworm (HW) Antigen test Kit (Zoetis, Florham Park, NJ) and the SNAP® Heartworm RT (IDEXX Laboratories, Inc., Westbrook, ME) to the well-based ELISA DiroChek® Heartworm Antigen Test Kit (Zoetis, Florham Park, NJ).

Methods

Canine plasma samples were either received at the Auburn Diagnostic Parasitology Laboratory from veterinarians submitting samples for additional heartworm testing (n = 100) from 2008 to 2016 or purchased from purpose-bred beagles (n = 50, presumed negative) in 2016. Samples were categorized as “positive,” “borderline” or “negative” using our established spectrophotometric cutoff value with the DiroChek® assay when a sample was initially received and processed. Three commercially available heartworm antigen tests (DiroChek®, Witness® HW, and SNAP® RT) were utilized for simultaneous testing of the 150 samples in random order as per their package insert with the addition of spectrophotometric optical density (OD) readings of the DiroChek® assay. Any samples yielding discordant test results between assays were further evaluated by heat treatment of plasma and retesting. Chi-square tests for the equality of proportions were utilized for statistical analyses.

Results

Concordant results occurred in 140/150 (93.3%) samples. Discrepant results occurred in 10/150 samples tested (6.6%): 9/10 occurring in the borderline heartworm (HW) category and 1/10 occurring in the negative HW category.

The sensitivity and specificity of each test compared to the DiroChek® read by spectrophotometer was similar to what has been reported previously (Witness®: sensitivity 97.0% [94.1–99.4%], specificity 96.4% [95.5–100.0%]; SNAP® RT: sensitivity 90.9% [78.0–100.0%], specificity 98.8% [96.0–100.0%]). There were significant differences detected when comparing the sensitivities of the SNAP® RT and the Witness® HW to the DiroChek® among the 150 total samples (p = 0.003) and the 50 “borderline” samples (p = 0.001).

Conclusions

In this study, the sensitivity of the Witness® HW was higher than the sensitivity of the SNAP® RT when compared with the DiroChek® test results prior to heat treatment of samples.

  相似文献   

12.
Objective: The aim of our study was to compare the effects of a vegetarian and a conventional diet on thigh adipose tissue distribution in subjects with type 2 diabetes (T2D).

Methods: Seventy-four subjects with T2D were randomly assigned to either follow a vegetarian diet (V, n = 37) or a control group who followed an isocaloric conventional anti-diabetic diet (C, n = 37). Both diets were calorie restricted (?500 kcal/day). To measure insulin sensitivity, the hyperinsulinemic (1 mU.kg?1.min?1) isoglycemic clamp was conducted. β-Cell function was assessed using a mathematical model after a test meal. Magnetic resonance imaging of the thigh was performed. All subjects were examined at 0, 3, and 6 months. Statistical analyses were performed using repeated measures analysis of variance and a multivariate regression model.

Results: Greater reduction was observed in total leg area in V (?13.6 cm2 [95% confidence interval [CI], ?14.2 to ?12.9] in V vs ?9.9 cm2 [95% CI, ?10.6 to ?9.2] in C; Gxt p < 0.001). The reduction in subcutaneous fat was comparable in response to both diets (Gxt, p = 0.64). Subfascial fat was reduced only in response to a vegetarian diet (?0.82 [95% CI, ?1.13 to ?0.55] cm2 in V vs ?0.44 [95% CI, ?0.78 to +0.02] cm2 in C; Gxt, p = 0.04). The reduction in intramuscular fat tended to be greater in response to a vegetarian diet (?1.78 [95% CI, ?2.26 to ?1.27] cm2 in V vs ?0.57 [95% CI, ?1.06 to ?0.09] cm2 in C; Gxt, p = 0.12). Changes in subcutaneous and subfascial fat correlated with changes in glycated hemoglobin (HbA1c), fasting plasma glucose, and β-cell insulin sensitivity. After adjustment for changes in body mass index (BMI), correlations remained significant for changes in fasting plasma glucose and β-cell insulin sensitivity and with changes in triglycerides.

Conclusions: Our data indicate the importance of both subcutaneous and subfascial fat in relationship to glucose and lipid metabolism.

Abbreviations: BMI , body mass index; C , control group; FPG , fasting plasma glucose; Gxt , interaction between group and time; HbA1c , glycated hemoglobin; MCR , metabolic clearance rate of glucose; OPLS , orthogonal projections to latent structure; T2D , type 2 diabetes; V , vegetarian group  相似文献   

13.
IntroductionThe Self Evaluation of Food Intake (SEFI®) is a simple tool to assess food intake.AimsTo evaluate the validity of SEFI® to screen malnutrition compared to the Mini Nutritional Assessment (MNA)® as the reference method (primary) and other screening tools (secondary); to assess the feasibility of SEFI® (secondary) in older people living in a nursing home.MethodsQuantitative, non-interventional, cross-sectional, monocentric pilot study. Patients were included in a 143-beds nursing home. The SEFI® visual analogue scale (VAS) from 0 to 10, and the evaluation of consumed portions of served food by the general practioner (SEFI® consumed portions) were performed after the MNA®. Malnutrition was defined as MNA®<17.StatisticsYouden method and receiver operating characteristic (ROC) curves.ResultsOut of 128 patients, 93 were included: 72% women, mean age (±SD), 88 ± 7 yr, body mass index, 25.9 ± 6.1, MNA®<17, 26% (24/93), SEFI® consumed portions ≤50%, 29% (27/93) of patients. The feasibility of SEFI®  VAS and consumed portions were respectively 0 and 100% (93/93). The predictive performance of SEFI® consumed portions for the diagnosis of malnutrition was good: area under the curve = 0.81 [95% confidence interval (CI), 0.69–0.93]; sensitivity 75.0% (n = 18/24, 95%CI, 57.7–92.3), specificity 87.0% (n = 60/69, 77.0–94.9), positive predictive value 66.7% (n = 18/27, 48.9–84.4), and negative predictive value 90.9% (n = 60/66, 80.0–93.9).ConclusionsSEFI® is feasible and useful for detecting malnutrition in nursing home residents.  相似文献   

14.
Background

Prior work has shown that the levels of moxidectin in dogs treated with Advantage Multi® for Dogs (Bayer Animal Health) remain at a high plasma concentration for the full month after application. The objective of this study was to demonstrate the efficacy of 10% imidacloprid + 2.5% moxidectin topical solution (Advantage Multi® for Dogs, also known as Advocate® for Dogs) for the prevention of heartworm infection and disease 30 days after just one application.

Methods

Two groups of eight dogs each were included. Dogs in Group 1 received the product (Advantage Multi® for Dogs) while those in Group 2 remained as nontreated controls. All dogs entering the study completed a physical examination including examination for Dirofilaria immitis antigen and circulating microfilariae. Dogs in Group 1 were treated on Study Day (SD) –30 as per the label recommendation. Thirty days later (SD 0) dogs in Groups 1 and 2 were subcutaneously infected in the inguinal region with approximately 50 infective third-stage D. immitis larvae (“Missouri” isolate). Blood was collected on SDs 120 and 147 for examination for D. immitis antigen and circulating microfilariae. On SD 148, all animals were euthanized and necropsied for recovery of adult heartworms. All procedures were performed in accordance with the VICH GL9 guidelines.

Results

Examination and worm counts made at necropsy showed no heartworms in the treated dogs (Group 1) compared with six of eight nontreated dogs (Group 2) with heartworms (range of 2–33). The treated dogs (Group 1) had significantly fewer heartworms (p < 0.05) compared with the nontreated controls (Group 2).

Conclusion

The results demonstrated that 10% imidacloprid + 2.5% moxidectin topical solution (Advantage Multi® for Dogs) is efficacious for the prevention of heartworm infection and disease all month long with no observation of treatment-related adverse events.

  相似文献   

15.
Objective: To investigate the influence of room temperature on finger blood flow (FBF) change in healthy subjects exposed to short-term grasping of a vibrating handle under different room temperatures. Methods: FBF was measured using a blood flowmeter in six male subjects on the dorsum of the middle phalanx of third finger in both hands once at the end of every minute for an equal duration of 5 min at pre-exposure, during exposure to grasping of vibrating handle with sinusoidal vibration and after exposure. Vibration was generated with a frequency of 125 Hz and an rms acceleration of 40 m/s2. Measurements were conducted in four room temperatures of 15±1, 20±1, 25±1 and 30±1°C. Results: Compared with the baseline measurements in the exposed hand during grasping of vibrating handle most significant increase in FBF was observed at 15±1°C (P<0.001) and least at 30±1°C (P<0.05), and after vibration least significant FBF was found at 25±1°C (P<0.05). In case of the unexposed hand significant increase in FBF was exhibited at 20±1°C (P<0.01) and 30±1°C (P<0.01) during vibration, and only at 15±1°C (P<0.05) after vibration. Conclusions: Response in FBF due to grasping of vibrating handle was of different patterns from the baseline measurement under different room temperature conditions in both exposed and unexposed hands and it was influenced by room temperature. Overall, the influence was greater at lower test room temperature, inducing more significant increase in FBF.  相似文献   

16.
Background: Several methods for the treatment of colon cancer have been introduced, but none of them are safe and effective. We planned to evaluate the inhibitory effect of protein extract of licorice root on HT-29 and CT26 cell lines proliferation and apoptosis. Methods: Protein extract of licorice root was prepared in phosphate-buffered solution, and SDS-PAGE was used to isolate its fractions. HT-29, CT-26, and HEK293 cell lines were treated with various concentrations of the fractions and full extract of licorice. Cytotoxicity of licorice at various concentrations was assessed using MTT assay. Flow cytometry analysis was applied to evaluate the apoptosis. Results: Our results demonstrated that the concentrations of 5 μg/mL from 25 to 33 kDa fraction and concentration of 8 μg/mL from 62 kDa fraction had a significant inhibitory effect on both cancerous cell lines (P < 0.05), with no significant effect on the noncancerous cell line. The concentrations of 50 and 100 μg/mL from full extracts significantly increased apoptosis in CT26 cells [35.52 ± 7.5 (P = 0.048*) and 47.72 ± 8 (P 0.026*), respectively], but not in HT29 and noncancerous cell lines. Conclusions: Protein compounds of licorice showed anticancer properties and were able to induce apoptosis in both human colon cancer and mouse colon carcinoma cell lines.  相似文献   

17.
Abstract

Aim: To investigate how day center attendees with psychiatric disabilities perceived their worker role and the importance of current work situation and personal factors in that respect.

Methods: Two-hundred attendees completed the Worker Role Self-assessment and questionnaires addressing possible predictors of the worker role: current employment situation, satisfaction with that situation, and a personal factor (encompassing self-esteem, self-mastery and engagement). Structural equation modeling was used.

Results: A model indicated two worker role factors; belief in a future worker role (WR1) and current capacities and routines (WR2). WR1 was positively influenced by having a job, younger age and the personal factor. Satisfaction with current work situation (usually unemployment) was negatively associated with WR1. The personal factor was single predictor of WR2. The attendees rated WR2 more positively than WR1.

Conclusions: The personal factor was crucial for both WR1 and WR2. Work-related factors were only important for WR1. The more negative rating of belief in a future worker role may be interpreted as mistrust in the services. The attendees’ positive ratings of capacities indicate, however, that they had a rehabilitation potential to develop. Enhancing self-esteem, mastery and engagement may be an avenue for staff in efforts to support the attendee’s worker role.  相似文献   

18.
Background: Aging adversely affects nitrogen accretion during health, but its effect during critical illness is unknown. Nitrogen balance (NB) response to varying protein intakes was compared between critically ill, older and younger patients. Methods: Adult patients admitted to the trauma intensive care unit, given enteral or parenteral nutrition, and who had a NB determination within 5–14 days after injury were evaluated. Patients with renal or hepatic disease were excluded. Patients were categorized as older (≥60 years) or younger (18–59 years of age). Data are given as mean ± SD or median [interquartile range]. Results: Fifty‐four older (69 [65, 77] years) and 195 younger (35 [27, 47] years) patients were evaluated. NB was blunted for the older patients with an observed trending improvement in NB from ?13.5 ± 5.5 to ?5.6 ± 8.8 g/d (P = NS) noted at 1.5?1.99 g/kg/d. NB improved from ?22.2 ± 8.2 to ?11.8 ± 9.9 g/d (P = .05) at 1–1.49 g/kg/d and modestly thereafter for each 0.5‐g/kg/d increase in protein intake for the younger patients. Serum urea nitrogen concentration during the NB was highly variable but overall greater for the older patients (20 [14, 33] vs 15 [10, 20] mg/dL, P = .001). Conclusions: Improvement in nitrogen accretion was blunted at lower protein intakes in critically ill, older patients compared with younger patients. Individualization of protein intake is warranted.  相似文献   

19.
ABSTRACT

Inadequate health literacy is a common problem among older adults and is associated with poor health outcomes. Insight into the association between health literacy and health behaviors may support interventions to mitigate the effects of inadequate health literacy. The authors assessed the association of health literacy with physical activity and nutritional behavior in community-dwelling older adults. The authors also assessed whether the associations between health literacy and health behaviors are mediated by social cognitive factors. Data from a study among community-dwelling older adults (55 years and older) in a relatively deprived area in The Netherlands were used (baseline n = 643, response: 43%). The authors obtained data on health literacy, physical activity, fruit and vegetable consumption, and potential social cognitive mediators (attitude, self-efficacy, and risk perception). After adjustment for confounders, inadequate health literacy was marginally significantly associated with poor compliance with guidelines for physical activity (OR = 1.52, p = .053) but not with poor compliance with guidelines for fruit and vegetable consumption (OR = 1.20, p = .46). Self-efficacy explained 32% of the association between health literacy and compliance with physical activity guidelines. Further research may focus on self-efficacy as a target for interventions to mitigate the negative effects of inadequate health literacy.  相似文献   

20.
Objective: This research was conducted to determine if altered environmental temperatures would affect the interactive developmental toxicity of radiofrequency (RF) radiation and the industrial solvent, 2-methoxyethanol (2ME). This is important because RF radiation is used in a variety of workplaces that have poorly controlled environmental temperatures, and many workers are concurrently exposed to various chemicals. Furthermore, we have previously demonstrated that combined exposure to RF radiation (10 MHz) and 2ME produces enhanced teratogenicity in rats. Methods: RF radiation sufficient to maintain colonic temperatures at the control value (38°), 39.0° or 40.0 °C for 2 or 4 h combined with either 0 or 100 mg/kg 2ME at environmental temperatures of 18°, 24° and 30 °C (65°, 75°, and 85 °F) were given on gestation day 13 to Sprague-Dawley rats. Dams were killed on gestation day 20, and the fetuses were examined for external malformations. Results and conclusions: Environmental temperature does affect the specific absorption rate (SAR) necessary to maintain a specific colonic temperature but does not affect the interactive developmental toxicity of RF radiation and 2ME in rats. These results, consistent with the literature, add to the evidence that the developmental toxicity of RF radiation (combined or alone) is associated with colonic temperature, not with SAR. Received: 17 September 1997 / Accepted: 13 February 1998  相似文献   

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