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1.
Impaired vagal heart rate control in coronary artery disease. 总被引:1,自引:1,他引:0
K E Airaksinen M J Ik?heimo M K Linnaluoto M Niemel? J T Takkunen 《Heart (British Cardiac Society)》1987,58(6):592-597
Heart rate variation in deep breathing, a sensitive non-invasive measure of cardiac parasympathetic activity, was measured in 63 patients with coronary artery disease, in 22 patients with atypical chest pain, and in 20 healthy symptom free volunteers. There was significantly less heart rate variation in deep breathing in the patients with coronary artery disease than in the healthy subjects. Twenty patients (32%) with coronary artery disease had lower than normal variation in heart rate. The patients with chest pain showed an intermediate heart rate response to deep breathing. Sinus arrhythmia in the patients with coronary artery disease was not related to the functional class, medication, number or location of narrowed vessels, or to the left ventricular ejection fraction, and end diastolic pressure. These results suggest that impairment of the parasympathetic nervous function is common in coronary artery disease. 相似文献
2.
Tim Söderlund Ilkka Tulikoura Mika Niemelä Lauri Handolin 《European journal of trauma and emergency surgery》2009,35(5):455-462
Objective:
The aim of the present study was to characterise traumatic deaths occurring in the emergency room (ER) and to assess retrospectively the quality of given emergency care by evaluating whether any of the deaths could be identified as potentially preventable. 相似文献3.
Spherical bioactive glass 13-93 particles, with a particle size distribution of 50-125 microm, were combined with bioabsorbable poly-L,DL-lactide 70/30 using twin-screw extrusion. The composite rods containing 0, 20, 30, 40 and 50 wt% of bioactive glass were further self-reinforced by drawing to a diameter of approximately 3 mm. The bioactive glass spheres were well dispersed and the open pores were formed on the composite surface during drawing. The initial mechanical properties were studied. The addition of bioactive glass reduced the bending strength, bending modulus, shear strength, compression strength and torsion strength of poly-L,DL-lactide. However, the strain at maximum bending load increased in self-reinforced composites. Initially brittle composites became ductile in self-reinforcing. The bioactivity was studied in phosphate buffered saline for up to 12 days. The formation of calcium phosphate precipitation was followed using scanning electron microscopy and energy dispersive X-ray analysis. Results showed that the bioactive glass addition affected the initial mechanical properties and bioactivity of the composites. It was concluded that the optimal bioactive glass content depends on the applications of the composites. 相似文献
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Laine TP Ahonen A Torniainen P Heikkilä J Pyhtinen J Räsänen P Niemelä O Hillbom M 《Molecular psychiatry》1999,4(2):189-91, 104-5
Dopaminergic transmission has been suggested to be a main mechanism mediating reinforcement, withdrawal and craving associated with alcohol addiction. We measured here striatal dopamine (DA) transporter binding from 27 alcoholics within 4 days after cessation of prolonged heavy drinking and after a 4-week period of abstinence with single photon emission computed tomography (SPECT) using a cocaine analogue, iodine-123-beta-CIT. Controls were 29 healthy volunteers. Blind quantitative analyses of the SPECT data revealed markedly lower DA transporter binding in alcoholics on admission for detoxification than in the non-alcoholic controls. After a 4-week period of abstinence DA transporter binding increased significantly in the alcoholics (P<0.0001) reaching the levels of the healthy controls. The most substantial recovery in DA transporter binding occurred during the first 4 days of abstinence. The data indicate that prolonged heavy drinking decreases DA transporter binding and disturbs synaptic dopamine transport. This may sensitize alcoholics to dopaminergic transmission, which may lead to early relapse after ethanol withdrawal. 相似文献
6.
Welling I Andersson IM Rosen G Räisänen J Mielo T Marttinen K Niemelä R 《The Annals of occupational hygiene》2000,44(3):219-225
The transportation of gaseous contaminant from a low and moderate low impulse (momentum<1 m s(-1)) source to the breathing zone was studied in a uniform air stream flow. Results of the effects of the direction and the velocity of principal air flow, convection due to a human body, arm movement of a human being and the type of source on the concentration profiles are presented. Three important results were obtained. Firstly, for a given low and moderate impulse low impulse contaminant source in the near field of a worker, his/her orientation relative to the principal air flow direction is the most important factor in reducing occupational exposure, with an air velocity of about 0.3 m s(-1). Secondly, the effect of convection resulting from body heat on air flow was lower than expected. Thirdly, arm movements influence contaminant dispersion, and should be included when models assessing exposure are developed. The present data can also be used to validate existing computational fluid dynamic (CFD) models. 相似文献
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Douglas P. Gross Alexander K. Asante Maxi Miciak Michele C. Battié Linda J. Carroll Ambrose Sun Marti Mikalsky Rene Huellstrung Riikka Niemeläinen 《Journal of occupational rehabilitation》2014,24(4):617-630
Purpose Functional capacity evaluations (FCE) are used to identify work abilities and are commonly integrated into rehabilitation programs. We studied whether integrating FCE into rehabilitation leads to better outcomes for injured workers. Methods A cluster randomised controlled trial was conducted at a workers’ compensation rehabilitation facility (registration ISRCTN61284905). Clinicians were randomised into 2 groups: 1 group used FCE while another conducted semi-structured functional interviews. Outcomes included recommendations following assessment, rehabilitation program outcomes including functional work levels and pain intensity, as well as compensation outcomes at 1, 3, and 6 months after assessment. Analysis included Mann–Whitney U, Chi square and t tests. Results Subjects included 225 claimants of whom 105 were tested with FCE. Subjects were predominantly employed (84 %) males (63 %) with sub-acute musculoskeletal conditions (median duration 67 days). Claimants undergoing FCE had ~15 % higher average functional work levels recommended at time of assessment (Mann–Whitney U = 4,391.0, p < 0.001) but differences at other follow-up times were smaller (0–8 %), in favour of functional interviewing, and not statistically significant. Clinically important improvement during rehabilitation in functional work level (0.9/4, SRM = 0.94), pain intensity (2.0/10, SRM = 0.88) and self-reported disability (21.8/100, SRM = 1.45) were only observed in those undergoing the functional interview. Conclusions Performance-based FCE integrated into occupational rehabilitation appears to lead to higher baseline functional work levels compared to a semi-structured functional interview, but not improved RTW rates or functional work levels at follow-up. Functional interviewing has potential for efficiency gains and higher likelihood of clinically important improvement following rehabilitation, however further research is needed. 相似文献