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961.
Propofol is a commonly used anesthetic agent, and it attenuates hypoxic ventilatory response in humans. Propofol reduce in vivo and in vitro carotid body responses to hypoxia as well as to nicotine in experimental animals. In the present study we examined the effects of propofol on carotid body responses to hypercapnia and K(+)-induced carotid body activation and compared these effects with hypoxia in an in vitro rabbit carotid body preparation. Hypoxia, hypercapnia and potassium increased the carotid sinus nerve activity and propofol attenuated the chemoreceptor responses to all three stimuli. However, the magnitude of propofol-induced attenuation was greater for hypercapnic and K(+)-induced carotid body activation compared to the hypoxic response. These observations suggest that propofol-induced attenuation of the hypoxic response is partly secondary to depression of chemoreceptor response to hypercapnia inhibiting the synergistic interactions between O(2) and CO(2) and may involve CO(2)/H(+) sensitive K(+) channels.  相似文献   
962.
The aim of this study was to investigate the coordination between the innermost muscle layer of the ventro-lateral abdominal wall, the transversus abdominis (TrA), and other trunk muscles, in reaction to a load-release without the postural demand of keeping the trunk upright. Eleven healthy male volunteers participated. Intramuscular fine-wire electromyography (EMG) was obtained bilaterally from the TrA, rectus abdominis (RA), obliquus externus (OE) and erector spinae (ES) muscles. The subjects lay on their right side on a horizontal swivel-table with immobilized pelvis and lower limbs and with the trunk strapped to a movable platform allowing for trunk flexion and extension. Subjects maintained trunk flexion or extension at different force levels against a static resistance, which was suddenly released. They were instructed to resume the start position as fast as possible. EMG signals were analysed with respect to amplitude and timing of muscle activation. Following released static flexion, TrA increased its activity in synergy with ES. Also in released static extension, TrA increased its activity, but now in synergy with RA and OE. The direction-independent activation of TrA indicates a role of this muscle in controlling inter-segmental movements of the lumbar spine. This function was not accompanied by an early activation of TrA as has been shown previously for trunk perturbations in standing, i.e. a situation with an additional demand of maintaining the trunk posture upright against gravity.  相似文献   
963.
Antibodies against hydrophobic antigens are common in several autoimmune diseases. However, detection of such antibodies by standard immune-assays, such as ELISA, is problematic, in part because of the problems with coating hydrophobic molecules onto polystyrene multi-well plates. We describe a novel method of stably associating hydrophobic antigens to ELISA plates. By mixing the antigen with a hydrophobic molecule containing a hydrophilic anchor, we generate mixed lipid aggregates that can attach to ELISA plates, and are resistant to detergent wash. Using the ganglioside GM-1 and phosphatidylethanolamine conjugated to the hapten DNP (dinitrophenyl) as model antigens, we show that hydrophobic antigens incorporated into mixed lipid aggregates expose their antigenic determinants in a correct configuration. The detection limit of both GM-1 and DNP-PE was considerably improved compared to when these antigens were coated on ELISA plates using organic solvents. Furthermore GM-1 incorporated into mixed lipid aggregates can be detected by specific antibodies in patient serum. The method of incorporating hydrophobic antigens into mixed lipid aggregates for stable association to ELISA plates can presumably be applied to a vast array of hydrophobic antigens, and may well be developed into a large scale screening system for serum reactivity towards different hydrophobic antigens.  相似文献   
964.
965.
Celiac disease (CeD) is a disease more prevalent and multisymptomatic than was earlier recognized. Whereas prompt initiation of gluten-free diet (GFD) is beneficial in relieving the symptoms, an accurate CeD diagnosis is necessary also to avoid years of restricted diet on uncertain grounds. We propose a new diagnostic method, based on elution of deposited antibodies against transglutaminase (anti-tTG) from duodenal biopsies in patients with symptoms and screening serology analyses suggestive of CeD. The eluates were analyzed in a Phadia 250 fluoroimmunoassay, demonstrating elevated concentrations of anti-tTG in CeD patients, corresponding to serology and histopathology findings. In one case histology was inconclusive, displaying only unspecific inflammation, but eluted anti-tTG was positive. This patient has clinically improved following GFD. We conclude that our novel method represents a new tool in the diagnostic work up in CeD. The detection of deposited anti-tTG at the site of inflammation appears to provide a high sensitivity and specificity using a technique that is quick, simple and reliable. Further studies are needed for optimization and elucidation of suitable applications for this elution method.  相似文献   
966.
967.
968.
The study reports on the associations of infant and childhood anthropometric measurements, early growth, and the combined effect of birth weight and childhood body mass index with older age physical functioning among 1,999 individuals born in 1934-1944 and belonging to the Helsinki Birth Cohort Study. Physical functioning was assessed by the Short Form 36 scale. Anthropometric data from infancy and childhood were retrieved from medical records. The risk of lower Short Form 36 physical functioning at the mean age of 61.6 years was increased for those with birth weight less than 2.5 kg compared with those weighing 3.0-3.5 kg at birth (odds ratio (OR) = 2.73, 95% confidence interval (CI): 1.57, 4.72). The gain in weight from birth to age 2 years was associated with decreased risk of lower physical functioning for a 1-standard deviation increase (OR = 0.84, 95% CI: 0.75, 0.94). The risk of lower physical functioning was highest for individuals with birth weight in the lowest third and body mass index at 11 years of age in the highest third compared with those whose birth weight was in the middle third and body mass index at age 11 years was in the highest third (OR = 3.08, 95% CI: 1.83, 5.19). The increasing prevalence of obesity at all ages and the aging of populations warrant closer investigation of the role of weight trajectories in old age functional decline.  相似文献   
969.
Potatoes, especially mashed potatoes, are known to result in high glycaemic and insulinaemic responses. However, in most meals, potatoes are accompanied by other foods. The objective of the present study was to investigate how glycaemic and insulinaemic responses to a mashed potato meal changed when a high-fat food (rapeseed oil), a high-protein food (chicken breast) and/or salad were added to the meal. Healthy subjects (n 11) ingested the test meals once and the reference food (glucose solution) twice in a random order at 1-week intervals. Capillary blood samples were then drawn for 2 h, and glucose and insulin were analysed. The 2 h glycaemic responses to six mashed potato-containing meals varied more than twofold. The glycaemic index (GI) of pure mashed potato was 108, whereas combined with chicken breast, rapeseed oil and salad, it was only 54. The latter GI also differed considerably from its predicted value of 103, which was based on the individual GI of the components of the meal. The insulinaemic indices of the mashed potato-based meals varied between 94 and 148. Chicken breast in the meal increased the insulinaemic response, and rapeseed oil diminished it. However, the insulinaemic response to mashed potato with chicken breast and rapeseed oil was lower than that to mashed potato alone. In conclusion, the protein, fat and salad contents of a meal exert considerable influence on the glycaemic and insulinaemic responses to mashed potatoes. Furthermore, the estimation of the GI of a mixed meal by calculation is imprecise.  相似文献   
970.
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