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At least 55 records · Page 3Linked to original sources
PubMed1980

Purification of 2-oxo acid dehydrogenase multienzyme complexes from ox heart by a new method.

A new method is described that allows the parallel purification of the pyruvate dehydrogenase and 2-oxoglutarate dehydrogenase multienzyme complexes from ox heart without the need for prior isolation of mitochondria. All the assayable activity of the 2-oxo acid dehydrogenase complexes in the disrupted tissue is made soluble by the inclusion of non-ionic detergents such as Triton X-100 or Tween-80 in the buffer used for the initial extraction of the enzyme complexes. The yields of the pyruvate dehydrogenase and 2-oxoglutarate dehydrogenase complexes are many times greater than those obtained by means of previous methods. In terms of specific catalytic activity, banding pattern on sodium dodecyl sulphate/polyacrylamide-gel electrophoresis, sedimentation properties and possession of the regulatory phosphokinase bound to the pyruvate dehydrogenase complex, the 2-oxo acid dehydrogenase complexes prepared by the new method closely resemble those described by previous workers. The greatly improved yield of 2-oxo acid dehydrogenase complexes occasioned by the use of Triton X-100 or Tween-80 as solubilizing agent supports the possibility that the bulk of the pyruvate dehydrogenase complex is associated in some way with the mitochondrial inner membrane and is not free in the mitochondrial matrix space.

Animals↗
PubMed1994

[Nuclear magnetic resonance tomography as a functional diagnostic method. New approaches to non-invasive quantification of cerebral blood volume and blood flow].

This paper presents a brief introduction to the current status of cerebral blood volume and blood flow imaging with magnetic resonance imaging (MRI) techniques. A new method for the quantitative assessment of regional cerebral blood volume (rCBV) and regional cerebral blood flow (rCBF) on the basis of the indicator dilution theory is described and preliminary quantitative results from healthy volunteers are presented. The mean values for the rCBV are 8.27 +/- 1.85 ml/100 g for grey matter and 3.78 +/- 1.34 ml/100 g for white matter. The mean values for the rCBF are 44.8 +/- 11.29 ml/min/100 g for the grey matter and 20.88 +/- 8.42 ml/min/100 g for the white matter. These results are in good agreement with PET results from the literature.

Adolescent↗
PubMed1992

Small pupil enlargement during cataract extraction. A new method.

A new method for enlarging a small pupil during cataract extraction is described. The technique is simple and safe, and uses new instruments that reduce or entirely eliminate the need to incise or suture the iris. This method of pupil enlargement can be used for extracapsular cataract extraction and phacoemulsification procedures.

Cataract Extraction↗
PubMed1987

New method for measurement of hepatic blood flow in the rat using thermodilution method.

A new method for measurement of hepatic blood flow in the rat is described. The method involved the use of a thermodilution technique. A thermistor probe was placed in a right hepatic vein of the median lobe of the liver, and a thermal indicator was injected into the portal vein via a catheter. The hepatic blood flow was then estimated from changes in the blood temperature. Measured hepatic blood flow was 25.6 +/- 2.3 ml/min (mean +/- SD, n = 17) or 2.80 +/- 0.45 ml/min/g liver. These results are in a good agreement with other studies that used different techniques to estimate total hepatic blood flow in the rat. To verify this method, an in vitro isolated liver perfusion model was used. The actual flow rates determined by time collection of outflow and the measured flow rates estimated by the thermodilution technique were well correlated (r = 0.968, less than P .001). This new technique is simple and accurate and can be used for repeated serial measurements of hepatic blood flow in the same animal.

Animals↗
PubMedDate not supplied

Neutrophil killing of single microorganisms as measured by a new method.

A new method of measuring polymorphonuclear leukocyte (PMN) microbicidal activity was developed in which single colony forming units of Staphylococcus aureus were isolated in microtiter wells with or without PMN, centrifuged, and incubated overnight. The percentage of bacteria killed was determined by comparing the number of PMN-containing wells showing bacterial growth to PMN-free controls. This percentage was positively correlated with the number of PMN in each well and was reduced if plates were not centrifuged or if cytochalasin B was added. Killing of either S. aureus or Escherichia coli was enhanced using fresh serum activated by prior exposure to large numbers of E. coli. There was no enhancement using heated serum that had been exposed to E. coli, nor was there enhancement when S. aureus was preopsonized by exposure to fresh serum. This assay circumvents problems in assessing microbicidal activity where aggregation of organisms might otherwise be an issue.

Blood Bactericidal Activity↗
PubMed1989

Colposcopy and computer graphics: a new method?

A new method is herein described that uses the most recent computer science techniques to obtain digitalized colposcopic images that may be useful not only as documents, but also as research tools. Because computer graphics is a recent and ever-growing discipline, our method, too, might undergo considerable improvements: some possible improvements are hypothesized in the text. The most striking features of this method are the excellent quality of images, their easy reproducibility, and the reasonable cost.

Cervix Uteri↗
PubMed1983

Ejection fraction determination without planimetry by two-dimensional echocardiography: a new method.

A new method for determining ejection fraction by two-dimensional echocardiography was assessed in 60 patients undergoing angiography. In method A, the left ventricular minor axis was measured at the midventricular cavity level in end-systole and end-diastole using the apical four chamber view in the 60 patients. The left ventricular major axis was also measured from the left ventricular apex to the base of the mitral valve at end-systole and end-diastole. The ejection fraction was determined using a modified cylinder-ellipse algorithm. In method B, measurements of the left ventricular minor axis were made in 40 consecutive patients, at the upper, middle and lower thirds of the left ventricular cavity at end-systole and end-diastole of the same cardiac cycle and left ventricular major axis was measured as in method A. With use of the same algorithm, three regional ejection fractions were determined and averaged to yield the total ejection fraction. The two echocardiographic methods were compared with single plane cineangiography in all patients and with gated nuclear scanning in 14 patients. Reproducibility was assessed by interobserver comparison. Correlation was determined in all patients and then separately for those with echocardiographic wall motion abnormalities. The correlation coefficient for all patients was 0.79 (probability [p] less than 0.001) for method A and 0.90 (p less than 0.001) for method B. For patients with wall motion abnormalities, method A had a correlation coefficient of 0.38 (p less than 0.1) and method B showed much higher correlation with r = 0.82 (p less than 0.001). Corresponding values for methods A and B in patients without wall motion abnormality were 0.85 (p less than 0.001) and 0.88 (p less than 0.001), respectively. Unlike a previous study, this method directly measures fractional shortening of left ventricular major axis and ejection fraction values are not arbitrarily modified by type of wall motion abnormality. With this method, accurate measurement of ejection fraction can be made by two-dimensional echocardiography without planimetry. In the absence of echocardiographic wall motion abnormalities, a very simple method A suffices. If wall motion abnormalities are present, the regional ejection fraction method B provides excellent results.

Adult↗
PubMed1993

Immediate reconstruction following maxillectomy: a new method.

A new method for immediate reconstruction of the maxilla after resection is described. The ipsilateral pedicled temporalis muscle is tunneled into the defect and sagittaly split into two layers. The inner layer is used to line the nasal side. An individually shaped titanium mesh, tightly filled with free autogenous corticocancellous bone, is fixed by titanium screws to the remnant of the zygoma and contralateral maxilla. The outer layer of the split muscle covers the reconstruction, the temporalis fascia forming the oral side. The method resulted in good cosmetic appearance and permitted the re-creation of a maxillary alveolar ridge suitable for endosseous implants or a simple prosthesis.

Adolescent↗
PubMed1997

Transepithelial potential difference of a single gill filament isolated from the crayfish Astacus leptodactylus Esch.: a new method.

A new method is described that allows in vitro perfusion and transepithelial electrical potential measurements of a single filament (3-5 mm long; 200 microns in diameter) isolated from the podobranch of the crayfish Astacus leptodactylus. An electrophysiological study was carried out on the preparation to validate this technique. The good physiological quality of the isolated filament preparation has been established and results of continuous measurements of the potential difference under two perfusion conditions are reported. Filaments were perfused with Van Harreveld physiological saline inside and either with Van Harreveld saline or artificial fresh water outside. Large potential differences up to 150 mV between inside and outside of the filament were recorded. When filaments were symmetrically perfused, the behavior of the electrical potential difference allowed two populations of filaments to be distinguished.

Animals↗
PubMed1989

Vaginal reconstruction with an axial subcutaneous pedicle flap from the inferior abdominal wall: a new method.

A new method of vaginal reconstruction is reported. In the procedure, the left inferior abdominal wall flap with the subcutaneous pedicle containing epigastric superficial blood vessels and/or the circumflex iliac superficial vessel and the external pudendal vessel and their branches is raised and passed through an immediate extraperitoneal tunnel to be the artificial vagina. The operation is straightforward, quick, and safe. Thirty consecutive patients suffering from congenital absence of vagina have been treated. All flaps in the group, which were less bulky, survived completely. The follow-up survey was carried out from 6 months to more than 4 years postoperatively. There was no occurrence of hernia after surgery. The reconstructed vaginas in all patients were clean, soft, elastic, and expansible. Married patients indicated satisfaction with their sexual life.

Abdominal Muscles↗
PubMed1986

Selective bronchial intubation for one lung anaesthesia in thoracic surgery. A new method.

A new method for one lung anaesthesia in thoracic surgery is described. Separate lung ventilation is obtained with selective main bronchus intubation, by means of an appropriate cuffed tube inserted through a standard orotracheal tube. Ventilation is carried out separately through the bronchial tube on one side and the residual tracheal tube lumen on the other side. This method greatly simplifies the technique of bronchial intubation and offers many advantages over commercially available double-lumen tubes.

Anesthesia, Inhalation↗
PubMed1985

Dual-photon absorptiometry of mandibles: in vitro test of a new method.

A new method for non-invasive in vivo measurement of changes in bone mineral content (BMC) of mandibles, comprising two-dimensional dual-photon absorptiometry (GT45), has been developed and tested in vitro on mandibular specimens. The analysis showed that: 1) in vitro precision and accuracy of the methods are high, 2) effect of fat and soft tissue on photon attenuation is slight when scanning jaws and forearm bones, 3) BMC in units (U/cm2) in standard area, comprising mandibular base and body in left molar region, is representative for BMC in total mandibular base and body, 4) cortical bone constitutes the main part of measured BMC in mandibles, and 5) BMC of molar region is highly correlated to cortical bone mass in mm3/mm2 subperiosteal surface of standard locality anterior to and below mental foramen, measured by histomorphometry. GT45 seems suitable for in vivo estimation of BMC changes in edentulous jaws and in mandibular base and body of dentate mandibles in longitudinal and cross-sectional studies. The radiation dose is negligible.

Adipose Tissue↗
PubMed1985

Post mortem measurement of ventricular volumes of the heart. An analysis of errors and presentation of a new method.

A new method to determine ventricular volumes of the heart post mortem was developed. Atrioventricular valves are carefully closed with continuous monofilament sutures, and the ventricles are filled with liquid paraffin through the base of the aorta and pulmonary trunk using a standard filling pressure. The effect of various post mortem factors on the volumes of cardiac ventricles was studied using this method. Many factors, such as rigor mortis, time of measurement, mechanical handling of the heart and filling pressure used in the measurement have an effect on the ventricular volume. The volume of ventricles after formalin fixation is only about half of that of fresh hearts handled in the same way. The contraction caused by rigor mortis keeps the volume low and can be relaxed only by manipulation of the heart. The results of measurements are comparable only if the hearts have been manipulated in the same way, have been preserved for the same length of time and under the same conditions, and the volume has been measured using the same filling pressure.

Animals↗
PubMed1977

The effect of cimetidine in meal-stimulated gastric functions measured with a new method.

A new method to measure gastric functions after meal-stimulation without infusion of bicarbonate into the stomach is presented. Six healthy volunteers were investigated after stimulation of the gastric functions with a 300-ml fluid test meal with and without cimetidine infusion. Cimetidine reduced the acid output substantially but had no effect on gastric emptying.

Adolescent↗
PubMed1983

A new method for quantitative analysis of thallium-201 myocardial image-"corrected" circumferential profile method.

A new method for computer-assisted quantitative analysis of a thallium (Tl)-201 myocardial image ("corrected" circumferential profile method) was described. Since the Tl-201 myocardial image of a normal subject is not homogeneous, an attempt was made to correct for this non-homogeneity. Three groups of subjects were studied, including 10 normal volunteers (group A, mean age of 27.5 years), 14 patients with atypical chest pain and normal coronary arteriogram (group B, mean age of 56.7 years) and 16 patients with first transmural myocardial infarction (group C, mean age of 71.0 years). The myocardial images were acquired at rest at anterior, left anterior oblique (30 degrees and 60 degrees) and left lateral projections. With a scintigram, the left ventricle was outlined and divided into 24 radial segments by radii drawn from the center of the left ventricle. Average radioactivity per pixel in normal subjects was obtained in each segment and normalized to the highest segment (= 100%). The ratio of 100% to the mean of normalized radioactivity in percent in each segment from 10 normal volunteers was calculated and designated as a correction factor for each segment. After the correction of average radioactivity per pixel in each segment using this correction factor and after relating it to the highest radioactive segment, the mean (= 100%) and standard deviation (SD) were calculated and (100-4SD)% was defined as the normal lower limit. In the scintigram of groups B and C, "corrected" circumferential profiles were obtained from the regional radioactivity multiplied by the correction factor, normalized to the highest segment (100%) and compared with the lower normal limit. The ratio (%) of the area of patient's circumferential profile curve below the normal limit to the total area below the normal limit was obtained at each view and the sum of them was called the total "corrected" defect score. Infarct size analyzed by the "corrected" circumferential profile method correlated well with that analyzed by visual interpretation, and was useful in differentiating group C from group B.

Adult↗
PubMed1981

Preparation of viable islet cells from dogs by a new method.

A new method for the preparation of viable islet cells from the normal dog pancreas is described, based on the perfusion of the pancreatic duct with collagenase. Exposure of the acinar tissue to the highest concentrations of collagenase results in improved islet yield with decreased acinar contamination. After the selective digestion of the gland by ductal perfusion, mechanical dissociation liberates single cells and clumps. Analysis of the procedure by insulin yield and amylase attrition indicates a 57% B-cell recovery and a sixfold enrichment in B-cell concentration. The cells have been transplanted as autografts into dogs after pancreatectomy. In 5 of 7 transplanted dogs, normoglycemia was achieved postoperatively.

Animals↗