PubMed Health⌕ Search
Home/Archive/PubMed

PubMed · 4024902

Cochlear blood flow studied with microspheres. A comparison between two different modifications of the microsphere method.

H C Larsen·C Angelborg·A Axelsson
View original source ↗Export metadata ↓

Abstract

In albino rabbits, spontaneously hypertensive rats, and guinea pigs, cochlear blood flow was measured with the microsphere method, using radioactively labelled microspheres technique and a gammaspectrometer. This 'conventional' microsphere method was compared with a new technique for measurements of cochlear blood flow: a modification of the 'radioactive' microsphere technique and the soft surface specimen technique. Values obtained for cochlear blood flow by the two different methods were similar. Consequently, the microsphere surface technique is a suitable alternative to the classical radioactive microsphere method for blood flow determinations in the cochlea.

Explore related subjects

Acid-Base EquilibriumAnimalsBlood PressureCochleaCricetinaeMicrospheresRabbitsRatsRegional Blood FlowSpectrometry, GammaStrontium RadioisotopesComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

H C Larsen, C Angelborg, A Axelsson. Cochlear blood flow studied with microspheres. A comparison between two different modifications of the microsphere method.. https://doi.org/10.3109/00016488509182258

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2007

The weighted walking test as an alternative method of assessing aerobic power.

The aim of the present study was to determine maximal oxygen uptake (VO2max) directly during uphill walking exercise and to compare these values with those achieved during running and cycling exercise. Forty untrained students (20 males and 20 females) took part in three exercise tests. The running test was performed on a horizontal treadmill and the speed was gradually increased by 0.3 m . s(-1) every 3 min. The walking test was conducted on a treadmill inclined at 12% (speed of 1.8 m . s(-1)). The load was further increased every 3 min by the addition of a mass of one-twentieth of the body mass of the participant (plastic containers filled with water and added to a backpack carried by the participant). During the bicycle ergometry test, the workload was increased by 20 W every 2 min. All tests were performed until volitional exhaustion. During all tests, oxygen uptake, minute ventilation, tidal volume, respiratory frequency, heart rate, hydrogen ion concentration, base excess, and blood lactate concentration were analysed. The Pearson correlation coefficients between the weighted walking test and the commonly applied running and bicycle ergometry tests indicate a strong association with the new test in evaluating maximal oxygen uptake. The negligible differences in VO2max between the three tests for the male participants (running: 61.0 ml . kg(-1) . min(-1); walking: 60.4 ml . kg(-1) . min(-1); cycling: 60.2 ml . kg(-1) . min(-1)), and the fact that the females achieved better results on the walking test than the cycle ergometer test (running: 45.0 ml . kg(-1) . min(-1); walking: 42.6 ml . kg(-1) . min(-1); cycling: 40.1 ml . kg(-1) . min(-1)), confirm the suitability of the new method for evaluating aerobic power. The weighted walking test could be useful in the assessment of aerobic power in individuals for whom running is not advised or is difficult. In addition, the new test allows for determination of VO2max on small treadmills with a limited speed regulator, such as those found in specialist physiotherapy and fitness centres.

Acid-Base Equilibrium↗
PubMed2007

Mandatory protocol for treating adult patients with diabetic ketoacidosis decreases intensive care unit and hospital lengths of stay: results of a nonrandomized trial.

OBJECTIVE: To determine the effect of a mandatory protocol for treating diabetic ketoacidosis. DESIGN: Chart review of patients treated before and after protocol implementation. SETTING: University-affiliated U.S. public teaching hospital. PATIENTS: A total of 241 consecutive nonpregnant patients >18 yrs old admitted to a medical intensive care unit for diabetic ketoacidosis between January 2000 and January 2005. INTERVENTION: Implementation of a mandatory treatment protocol in May 2003. MEASUREMENTS: Intensive care unit and hospital lengths of stay, time to correction of anion gap and ketone clearance, and hypoglycemic episodes. RESULTS: Before protocol implementation, the mean +/- sd intensive care unit and hospital lengths of stay were 44 +/- 28 hrs and 91 +/- 73 hrs, respectively. After implementation, intensive care unit and hospital lengths of stay decreased 23% and 30%, to 34 +/- 18 hrs and 64 +/- 41 hrs, respectively (both p < .007). Time to anion gap closure and ketone clearance also decreased (both p < .05). No difference in the number of hypoglycemic episodes was observed. CONCLUSION: Implementing a mandatory protocol for treating adult patients with diabetic ketoacidosis decreases intensive care and hospital lengths of stay and time to anion gap closure and ketone clearance, without increasing the rate of hypoglycemia.

Acid-Base Equilibrium↗