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OBJECTIVE: To determine if there is a diurnal pattern in the clinical symptoms of HELLP (Hemolysis, Elevated Liver enzymes, Low Platelets) syndrome. STUDY DESIGN: A retrospective study was performed in 134 pregnancies complicated by HELLP syndrome. The medical records were reviewed to describe each HELLP episode. Time of day was divided into three periods, day, evening, and night. The following parameters were categorized according to the time of day: onset of symptoms, consultation by the doctor, initial blood sampling, diagnosis and decrease of symptoms. Biochemical parameters at clinical presentation and consecutive changes within 24 h were recorded. RESULTS: In 65 pregnancies 77 HELLP episodes were well documented. Times of onset of symptoms and consultation by the doctor were significantly higher during the evening and night (p < 0.001), whereas times of diagnosis and decrease of symptoms occurred significantly more during the day (p < 0.001). In only 49.3% of the cases were diagnostic laboratory criteria met at clinical presentation. This was mainly due to platelet values in excess of 100 x 10(9)/l. Several hours later (median 8 h, range 2-23) the decrease in platelets occurred. CONCLUSIONS: A diurnal pattern exists in the clinical symptoms of HELLP syndrome that is characterized by an exacerbation during the night and recovery during the day. There is a considerable delay between the onset of symptoms and the fulfillment of diagnostic laboratory criteria.  相似文献   
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1. Using a guinea-pig model of allergic asthma, we investigated the role of nitric oxide (NO) in allergen-induced airway hyperreactivity after the early asthmatic reaction, by examining the effects of the NO-synthase inhibitor N omega-nitro-L-arginine methyl ester (L-NAME) on the responsiveness to methacholine and histamine of isolated perfused tracheae from unchallenged (control) animals and from animals 6 h after ovalbumin challenge. 2. All animals developed airway hyperreactivity to inhaled histamine at 6 h after ovalbumin challenge, with a mean 3.11 +/- 0.45 fold increase in sensitivity to the agonist (P < 0.001). 3. In perfused tracheal preparations from the ovalbumin-challenged guinea-pigs, the maximal responses (Emax) to methacholine and histamine were significantly enhanced compared to controls, both after intraluminal (IL) and extraluminal (EL) administration of the contractile agonists. In addition, a small but significant increase in the pD2 (-log10 EC50) for IL and EL methacholine and for IL histamine was observed. As a consequence, the delta pD2 (EL-IL) for histamine was slightly decreased from 1.67 +/- 0.13 to 1.23 +/- 0.14 (P < 0.05). However, the delta pD2 for methacholine was unchanged (1.85 +/- 0.11 and 1.77 +/- 0.12, respectively; NS). 4. Incubation of control tracheae with 100 microM L-NAME (IL) significantly enhanced the Emax for both IL and EL methacholine and histamine to approximately the same degree as observed after ovalbumin challenge, with no effect on the pD2 and delta pD2 for both agonists. On the contrary, L-NAME had no effect on Emax and pD2 values of tracheal preparations from ovalbumin-challenged guinea-pigs. 5. L-NAME (10 microM-1 mM) had no effect on methacholine-induced contraction of isolated tracheal strip preparations obtained from control animals, indicating that L-NAME has no antimuscarinic effect on tracheal smooth muscle. 6. Histological examination of the intact tracheal preparations indicated epithelial and subepithelial infiltration of eosinophils after ovalbumin challenge. However, no apparent damage of the airway epithelium was observed in these preparations. 7. The results indicate that a deficiency of NO contributes to allergen-induced airway hyperreactivity after the early asthmatic reaction and that this deficiency appears not to be due to epithelial shedding.  相似文献   
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In this study, it is first of all investigated whether elderly and younger hospital patients differ with respect to satisfaction with several aspects of their stay in the hospital, medical and hospital knowledge, emotional state, seeking information, discussing problems and engaging in self-care. Second, it is investigated whether age differences on these variables can be explained by demographic variables, previous hospitalization experience, information received and personality characteristics on which elderly and younger patients differ. Results show that compared to younger patients, elderly patients are more satisfied, have less knowledge and a smaller number of emotional problems and are less active during hospital admission. These differences covary with, a more positive assessment of the information received, a stronger level of external control, a higher level of social desirability and stronger feelings of gratitude among elderly patients. These results are in line with Taylor's concept of the 'good patient'. Finally, based on the findings, measures are suggested for health workers to promote the well-being of elderly hospital patients.  相似文献   
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