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1.
Membrane-bound CD14 acts as a receptor for lipopolysaccharide (LPS) on monocytes/macrophages and neutrophils. Studies have suggested that the activation of monocytes/macrophages by the binding of LPS to membrane-bound CD14 may require the association of a signal-transducing molecule with membrane-bound CD14. The observation that non-CD14 expressing cells, such as endothelial cells, can nevertheless be activated by a complex of LPS and a soluble form of CD14 (sCD14) suggests that the receptor for this complex may be identical to the signal transducing molecule associated with membrane-bound CD14. The studies described show that two CD14-specific MoAb are able to block the LPS-induced activation of endothelial cells but do not affect the response of monocytes to LPS. This suggests that the interaction of the sCD14:LPS complex with endothelial cells is distinct from the interaction of membrane-bound CD14 with its putative signal-transducing molecule.  相似文献   
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Gestational diabetes mellitus (GDM) is the most common medical disorder complicating pregnancy that requires the services of a registered dietitian. Despite three international workshops on GDM, many questions remain regarding its epidemiology, pathophysiology, screening, diagnosis, and management. Registered dietitians encounter these controversial issues when working with women referred for GDM education and counseling. Nutrition intervention remains the cornerstone of therapy. The purpose of this article is not to provide practice guidelines but to review the literature and current practices in research centers across the United States. Registered dietitians are in a position to individualize nutrition care to each woman's needs and to participate in the decision-making process of nutrition management. J Am Diet Assoc. 1995; 95:460–467.  相似文献   
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Subjects cycled at a work load calculated to elicit 75% of maximal oxygen uptake on two occasions: the first to fatigue (34.5 ± 5.3 min; mean ± SE), and the second at the same workload and for the same duration as the first. Biopsies were obtained from the quadriceps femoris muscle before and immediately after exercise, and 5 min post-exercise. Before the first experiment, muscle glycogen was lowered by a combination of exercise and diet, and before the second, experiment muscle glycogen was elevated. In the low glycogen condition (LG), muscle glycogen decreased from 169 ± 15 mmol glucosyl units kg-1dry wt at to rest to 13 ± 6 after exercise. In the high glycogen condition (HG) glycogen decreased from 706 ± 52 at rest to 405 ± 68 after exercise. Glycogen synthase fractional activity (GSF) was always higher during the LG treatment. During exercise in the HG condition, those subjects who cycled for < 35 min (n= 3) had GSF values in muscle which were lower than at rest, whereas those subjects who cycled for > 35 min (n= 4) had values which were similar to or higher than at rest. Thus the change in GSF in muscle during HG was positively related to the exercise duration (r= 0.94; y = 254–17x + 0.3x2; P < 0.001) and negatively related to the glycogen content at the end of exercise (r=–0.82; y= 516–2x + 0.001x2; P < 0.05). During LG exercise GSF remained constant. GSF increased markedly after 5 min post-exercise in both HG and LG conditions. cAMP dependent protein kinase activity increased similarly during both LG and HG exercise and reverted to the preexercise values 5 min post-exercise. It is concluded that muscle contraction decreases GSF, but low glycogen levels can attenuate or abolish the decrease in GSF. The rapid increase of GSF during recovery from exercise does not require glycogen depletion during the exercise.  相似文献   
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Superoxide release in neutrophils and sera levels of interleukin 8 (IL-8) were determined in 15 patients with complicated acute myocardial infarction (MI) and 15 patients with uncomplicated MI. All patients showed increased superoxide release in unstimulated and stimulated neutrophils compared with healthy control subjects, indicating priming of these cells. Superoxide release of unstimulated or stimulated neutrophils was found to be significantly higher in patients with complicated MI than in patients with uncomplicated MI. Thrombolytic therapy did not affect the rates of superoxide release. The neutrophil chemoattractant/activator IL-8 was detected in the sera of all patients, with significantly higher levels in those with complicated MI. The highest levels of IL-8 were detected at admission to the Coronary Care Unit and significantly decreased thereafter, suggesting its contribution to neutrophil-mediated tissue injury. The high levels of IL-8 may be one of the major contributors to the priming of neutrophils in these patients.  相似文献   
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Possible influences of changes in the CO2-respiratory drive on the ability to judge lung volumes and the possible effects of such judgments on the ventilatory CO2-responsiveness were studied in healthy subjects. The psychophysical relationships between objective and subjective magnitudes of lung volumes were determined at normocapnia, at three different levels of hypercapnia (breathing 1–3% CO2 in air) and at hypocapnia (after volitional hyperventilation). The relationships, expressed by a power function with the mean exponent 1.5 (SD±0.3), were analyzed with respect to slope, intercept and correlation coefficient of the regression lines. None of these parameters was affected by variations in end-tidal PCO2 or by the concomitant changes in ventilation. In the ‘attentive’ pre-judgment breathing (APJB) the ventilatory response to CO2 was lower than during non-attentive breathing in three or four subjects. It is speculated that in these subjects the CO2-responsiveness was depressed by the increased attention during APJB. The question whether volitional hyperventilation gave rise to any specific post-hyperventilatory breathing pattern was analyzed. The results showed that the majority of post-hyperventilatory breathing pattern was apnoeic or hypopnoeic in character.  相似文献   
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The possibility of "recurarization" after antagonism of thecompetitive neuromuscular block with anticholinesterases wasstudied. Observations were made on the time-course of the blockin five patients at risk from recurarization because of multipleorgan failure and who demonstrated unusually prolonged blockade.In none of these patients did the block recur. We conclude that,provided spontaneous recovery of neuromuscular transmissionhas made progress before the antagonism, and that the patientdoes not deteriorate or become exhausted afterwards, recurarizationis unlikely.  相似文献   
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Aim To give an overview of indications for the use of botulinum toxin A (BoNT‐A) treatment for children with obstetric brachial plexus injury (OBPI), and to present the best available evidence of the effectiveness of this treatment. Method Searches were performed in Cinahl, Cochrane Library, Embase, PubMed, and Web of Science, using the keywords ‘botulinum’ and ‘plexus’, to identify articles reporting on the use of BoNT‐A as a treatment for children with OBPI. Studies found through the references of related articles were also selected. Results Ten full‐text papers and six congress abstracts were included, involving 343 children. Four groups of indications could be identified: internal rotation/adduction contracture of the shoulder, limited active elbow flexion, limited active elbow extension, and pronation contracture of the lower arm. Overall, positive results were reported for all except the indication for limited active elbow extension. However, only one study was comparative in nature; all others were classified as having a low level of evidence. There was a large variation in outcome measures. Interpretation To provide better evidence for the already partly promising results of BoNT‐A treatment for children with OBPI, multicentre randomized controlled trials are needed.  相似文献   
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