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81.
Arterial blood-flow waveform measurement in intact animals: new digital radiographic technique 总被引:1,自引:0,他引:1
With a new radiographic method to determine the pulsatile flow pattern in an imaged artery, flow velocity is determined by tracking the movement of contrast material along the artery over time. Flow velocity is multiplied by an automatically determined cross-sectional area of the artery to determine blood flow. Pulsatile blood-flow waveforms were determined by radiographic and electromagnetic techniques in each femoral artery of four dogs while flow conditions were varied. Peak and average blood flows measured by the two techniques were highly correlated (r = .97 and .95, respectively). The closest agreement between the flow waveforms measured by the electromagnetic and radiographic techniques was found under normal flow conditions. The radiographically derived flow waveforms tended to be noisy at low blood-flow rates, and instantaneous blood-flow rates exceeding 700 ml/min were underestimated. 相似文献
82.
Chest radiographs of 18 newborns treated with endotracheal instillation of human surfactant for respiratory distress syndrome (RDS) were compared with those of 18 similar but untreated infants. In the treated infants, severity of RDS significantly improved after surfactant administration. Most treated infants (16/18) exhibited a left-to-right shunt, presumably through a patent ductus arteriosus; similar findings were noted in untreated infants (17/18). Complications of respiratory assistance in the treated infants included transient pulmonary interstitial emphysema (n = 1), pneumothorax (n = 1), and mild (n = 4) to moderate (n = 2) bronchopulmonary dysplasia; the incidences of these complications did not exceed those in untreated infants. In three treated infants, a transient interstitial lung disease developed 3-4 days after surfactant administration. 相似文献
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A recent report has questioned the safety of sumatriptan in asthmatic migraineurs. To investigate this, we have reviewed the sumatriptan clinical trial safety database of over 75 completed trials. Within the clinical trial database, 375 asthmatic patients were identified who treated 1214 migraine attacks with sumatriptan. The incidence and nature of adverse events in the asthmatic patient subgroup who received sumatriptan was similar to that in the complete clinical trial population. Six reports of asthma were recorded as adverse events, but only one case was classified by the investigator as related to treatment. There is no clinical or pharmacological evidence to suggest that the safety profile of sumatriptan is altered in asthmatic patients compared to other migraine sufferers. 相似文献
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Lumbar myelography was performed with high volumes of iohexol (15-24 ml) at a concentration of 180 mgI/ml (average dose, 20 ml) in 48 patients. In 44 patients receiving more than the currently recommended upper dose limit of 17 ml, the frequency of headache (41%), nausea (14%), and vomiting (9%) was comparable to results for routine-dose lumbar metrizamide myelography. Overall, adverse reactions were more frequent, particularly at the highest dose levels, than reported for conventional-dose iohexol myelography. However, there were no occurrences of neuropsychiatric disorder, encephalopathy, or seizure. High-dose technique allows superior visualization of upper lumbar and conus detail and may be advantageous in patients with large subarachnoid spaces and in multi-level examinations. This study supports the results of previous trials that suggested the relative safety of iohexol as a contrast agent and extends those observations to a higher dose range. Because of the increased rate of adverse reactions at the highest dose levels (despite the absence of major adverse reactions), iohexol should continue to be used conservatively, with doses carefully tailored to each examination. 相似文献
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Ammini AC Sharma DC Gupta R Mohapatra I Kucheria K Kriplani A Takkar D Mitra DK Vijayaraghavan M 《Indian journal of pediatrics》1997,64(3):419-423
Familial male pseudohermaphroditism (MPH) due to 17, 20-desmolase deficiency is rare. Here we present two siblings with MPH
possibly due to 17, 20-desmolase deficiency. The first patient presented with unambiguous female external genitalia and hypergonadotrophic
hypogonadism. Chromosomal analysis revealed 46 XY. Ultrasound evaluation of pelvis revealed gonads in the inguinal canal,
and no uterus. These findings were confirmed on laparotomy. Histology revealed the gonads to be testes. The second patient
had ambiguous genitalia (perineoscrotal hypospadias, bifid scrotum with palpable gonads) with a 46 XY chromosomal pattern.
Both patients had high plasma 17-hydroxy progestrone (17 OHP), low normal dehydro epiandrosterone sulphate (DHEAS) and low
plasma testosterone. Plasma testosterone and DHEAS showed no response to ACTH or HCG. These features are compatible with the
diagnosis of 17, 20-desmolase deficiency. 相似文献