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At least 1,531 records · Page 85Linked to original sources
PubMed1986

Transcranial Doppler sonography. Examination technique and normal reference values.

The main application of ultrasound in neurology is the examination of extracranial arteries. Recently the Doppler sonographic measurement of flow velocity in the basal cerebral arteries through the intact skull was developed using a pulsed Doppler technique and 2 MHz emitting frequency. Doppler frequencies in systole and diastole were recorded in 51 healthy subjects at 0.5 cm steps along the middle (MCA), anterior (ACA) and posterior cerebral artery (PCA) as well as the basilar artery (BA). The averaged Doppler shift in the MCA was 2.3 +/- 0.4 kHz in systole and 1.15 +/- 0.25 kHz in diastole, in the ACA 1.8 +/- 0.35 kHz and 0.85 +/- 0.22 kHz, in the PCA 1.5 +/- 0.29 kHz and 0.74 +/- 0.18 kHz, in the BA 1.45 +/- 0.31 kHz and 0.72 +/- 0.22 kHz. Separation in four age groups showed a decrease of Doppler shift in the MCA of 20% from a mean age of 17 to 67 years. Static and dynamic compression tests were evaluated to assign transcranial Doppler signals to the MCA, ACA and PCA. No compression test was necessary for the identification of the BA insonated through the occipital foramen.

Adolescent↗
PubMed1982

Reference values for intramuscular pressure in the lower leg in man.

Intramuscular pressures in the anterior tibial and superficial posterior compartments of the lower leg were measured by the wick catheter technique in 34 healthy individuals (17 males and 17 females, mean age 42 years). The pressures were measured at rest, during and after exercise and during venous and arterial occlusion. The pressure was 1.1 (range 0.3-3.0) kPa in the anterior tibial and 0.5 (range 0.0-2.0) kPa in the superficial posterior compartment at rest. During exercise the intramuscular pressures rose to 3.5 (range 1.0-8.0) kPa and 0.9 (range 0.1-2.8) kPa respectively. The anterior tibial compartment pressures were lower in females than in males at exercise and lower in older than in younger persons at rest. After exercise the pressures were back to the pre-exercise levels within 5 min. Venous occlusion caused an increase in the pressure which was more marked in the anterior tibial compartment than in the superficial posterior compartment. Arterial occlusion did not cause any dramatic changes in intramuscular pressures, but there was a slight elevation during the period of reactive hyperaemia.

Adult↗
PubMedDate not supplied

Gastrointestinal studies in the green iguana: technique and reference values.

Five healthy green iguana (Iguana iguana) were used to determine appropriate technique and normal transit times for gastrointestinal contrast studies and to describe normal radiographic anatomy. The animals were maintained at 27-29 degrees C. There was rapid transit through a U shaped stomach, with a median gastric emptying time of 8 h, and median small intestinal transit and small intestine emptying times of 4 h and 16 h respectively. Median large colon transit and emptying times were 15 h and 66 h. Maintaining the iguana at a reduced ambient temperature increased all of these times. The vaso-vagal response or mechanical methods were adequate for restraint. A 25 ml/kg dose of a 25% w/v suspension of barium administered by stomach tube gave the best results. Lateral and ventrodorsal projections of the abdomen should be made immediately following the administration of the barium and at 1-hour intervals for the first 6 h and at 12-hour intervals thereafter until barium can be identified in the distal descending small colon.

Animals↗
PubMed1985

Screening coagulation tests in the cat: reference values based on direct venipuncture and catheterized samples.

Platelet count, prothrombin time, activated partial thromboplastin time, fibrinogen degradation products, fibrinogen, and modified thrombin time were determined in 46 healthy adult cats. Samples were obtained by direct venipuncture (pet cats, n=20) or through an 18 gauge intravenous jugular catheter (laboratory conditioned cats, n=26). Range, mean, standard error, and 95% confidence interval were tabulated for the 2 samples. A statistically significant difference between the two groups of cats (Student's t test, p <.05) was found for fibrinogen. No statistical difference was detected between the two groups of cats for the other laboratory values.

Journal Article↗
PubMed2005

Total body composition by DXA of 241 HIV-negative men and 162 HIV-infected men: proposal of reference values for defining lipodystrophy.

The aim of this study was to define standard values for fat mass distribution by dual-energy X-ray absorptiometry in human immunodeficiency virus (HIV)-negative men and to analyze factors associated with lipodystrophy in HIV-infected men. Total-body composition was analyzed in 241 HIV-negative men (controls) and 162 HIV-infected men. We created a fat mass ratio (FMR) as the ratio of the percentage of the trunk fat mass to the percentage of the lower limbs fat mass. We defined the FMR standard values as the mean value+/-standard deviation. We compared body mass index (BMI), fat mass percentage (%FM), lean mass (LM), bone mineral density (BMD), and FMR between the control group and HIV-infected men, by age range, according to prescription of treatment and presence of clinical lipodystrophy. The FMR standard value is equal to 1.3+/-0.2. The FMR was higher in treated HIV-infected men with or without clinical lipodystrophy. The FMR was similar for naïve HIV-infected men and controls. It was positively correlated with age, cumulative time on treatment, zidovudine, stavudine, or indinavir. BMD and fat mass were lower for treated and naïve HIV-infected men than for HIV-negative men. The FMR seems to be a valuable index for measuring fat mass distribution. We defined FMR standard values from the largest group of HIV-negative men to our knowledge. Applying FMR to HIV patients could help physicians to diagnose lipodystrophy earlier.

Absorptiometry, Photon↗