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91.
Nasal cavity volume and blood temperature along the nasal airways, reflecting the mucosal temperature, are considered to be the most important predictors of nasal air conditioning. The purpose of this study was to simultaneously in vivo measure intranasal air as well as mucosal temperature for the first time. Fifteen healthy subjects were enrolled into the study. Two combined miniaturized thermocouples were used for simultaneous recording of intranasal air and mucosal temperature within the anterior turbinate area close to the head of the middle turbinate without interruption of nasal breathing. The highest air and mucosal temperature values were detected at the end of expiration, the lowest values at the end of inspiration. The difference was statistically significant (P < 0.05). The mean mucosal temperature ranged from 30.2 ± 0.9 to 32.2 ± 0.8°C. The mean air temperature ranged from 28.5 ± 1.2 to 34.1 ± 0.7°C. The mean differences between air and mucosal temperature were 1.7 ± 0.5°C after inspiration and 1.9 ± 0.7°C after expiration. Simultaneous measurements of intranasal air and mucosal temperature are practicable. The detected temperature gradient between air and mucosa confirm a relevant heat exchange during inspiration and expiration. This gradient between air and mucosa is obligatory for heat and water exchange to ensure adequate nasal air conditioning.  相似文献   
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Optimization of a previously disclosed sorbitol dehydrogenase inhibitor (SDI, II) for potency and duration of action was achieved by replacing the metabolically labile N,N-dimethylsulfamoyl group with a variety of heterocycles. Specifically, this effort led to a series of novel, in vitro potent SDIs with longer serum half-lives and acceptable in vivo activity in acutely diabetic rats (e.g., 62, 67, and 69). However, the desired in vivo potency in chronically diabetic rats, ED90 less than or equal to 5 mg/kg/day, was achieved only through further modification of the piperazine linker. Several members of this family, including 86, showed better than the targeted potency with ED90 values of 1-2 mg/kg/day. Compound 86 was further profiled and found to be a selective inhibitor of sorbitol dehydrogenase, with excellent pharmacodynamic/pharmacokinetic properties, demonstrating normalization of sciatic nerve fructose in a chronically diabetic rat model for approximately 17 h, when administered orally at a single dose of 2 mg/kg/day.  相似文献   
94.
The nuclear medicine bleeding scan is frequently insufficient to locate sites of bleeding precisely, in spite of its great sensitivity. A small, hand-held Geiger-Müller counter, placed directly on exposed intestine in the operating room, enables precise location of the probable bleeding site. In three patients, the technique allowed a minimal amount of intestine to be resected, distinguished between large- and small-intestinal hemorrhage, and eliminated other foci as sites of bleeding.  相似文献   
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Fentanyl is in many neonatal intensive care units the sedative of choice. One side-effect is, however, the possibility of muscle and/or chest wall rigidity. A pregnant woman with a critical pulmonary valve stenosis had a balloon dilatation at 26 weeks of gestation. She was put on propranolol, but went into a severe cardiac failure. In week 31, she developed pregnancy induced hypertension. Periodically absent diastolic flow in the umbilical cord was demonstrated. A Caesarean section was performed using fentanyl as analgesia. A boy weighing 1440 g, had a 1 min Apgar score of 3 without respiratory movements. Mask ventilation was tried, but chest wall expansion was not achieved despite using high pressures. He was intubated and positive pressure ventilation attempted, with the same result. Despite the use of high pressures up to 60–70 cm H2O, no chest movement could be achieved. An intravenous line was established in order to give naloxone and pancuronium. Just before the drugs were given, chest wall movements were achieved and the heart rate normalized. Conclusion This is the first report on chest wall rigidity in a neonate after administration of fentanyl to the mother during Caesarean section. Received: 15 August 1997 and in revised form 30 January 1998 / Accepted 3 February 1998  相似文献   
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Aim: We have designed a study with the objective of describing the clinical impact of other viruses different from the respiratory syncytial virus (RSV) in hospitalized infants with bronchiolitis. Methods: A 3 year prospective study was conducted on infants admitted to the Paediatrics Department of the Severo Ochoa Hospital (Spain). We studied the frequency of 16 respiratory viruses. Clinical characteristics of RSV‐only infections were compared with other single agent viral infections. Results: Positive results were confirmed in 275 (86.5%) of the 318 children studied. A single virus was detected in 196 patients and 79 were dual or multiple viral infections. RSV was detected in 61.3% of total bronchiolitis. Rhinovirus (RV) was 17.4% of the identified virus, followed by human bocavirus (HBoV), adenovirus and metapneumovirus (hMPV). Only RV, HBoV and hMPV were significant as single infections. RSV patients were younger than HBoV (p > 0.0001) and hMPV (p = 0.025). Seasonality was clearly different between them. Children with RSV infection needed treatment in the intensive care unit more frequently than others. Conclusions: In hospitalized infants, RSV was the most frequent agent in bronchiolitis in winter, but other viruses were present in 47% of the patients. RV, HBoV and hMPV had a significant proportion of single infections. Clinical characteristics were similar amongst them, but seasonality was clearly different.  相似文献   
100.
The number of older patients with decreased capacity to independently perform a sit-to-stand transfer will increase during the next decade. It was hypothesized that an ergonomically modified bed prototype would either allow patients to stand up from the prototype independently or with reduced impact on the lower extremities. Standing up from the prototype was examined by force plate measurements in 30 patients of a geriatric rehabilitation hospital (median age 83.5 years). Nine of the patients were not able to stand up from the bed without arm rests, but were able to stand up with the help of arm rests. In those 21 patients, able to stand up even without arm rests, the use of arm rests caused a lower maximum vertical ground reaction force (p=0.03). No differences in quality concerning using or not using the armrests were documented neither for the time to stand up nor for symmetry of ground reaction force. In summary, the study shows that an ergonomically modified bed adds increased independency during the sit-to-stand transfer in selected patients. The reduction of peak vertical ground reaction force by using arm rests could be beneficial for certain patient groups.  相似文献   
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