Because catecholamines and digitalis have different effects on the time course of myocardial intracellular calcium concentration, their effects on the time course of left ventricular contraction and relaxation may also be different. To study this question, dogs were instrumented to measure left ventricular pressure and determine left ventricular volume from three ultrasonic dimensions. After fu...

Background and Objectives Intra-parenchymal brain surgical resection cavities usually contract in volume following low dose rate (LDR) brachytherapy implants. In this study, we systematically modeled and assessed dose variability resulting from such changes for I-125 versus Cs-131 radioactive sources. Methods Resection cavity contraction was modeled based on 95 consecutive patient cases, using ...

The prevalence of urinary symptoms increases with age and is a significant source of distress, morbidity, and expense in the elderly. Recent evidence suggests that symptoms in the aged may result from sensory dysfunction, rather than abnormalities of detrusor performance. Therefore, we employed a pressure/flow multichannel urethane-anesthetized mouse cystometry model to test the hypothesis that...

In order to assess potential improvement in abnormal left ventricular (LV) wall motion, eighteen subjects sixteen with obstructive coronary artery disease and LV asynergy and two with no evidence of organic heart disease were studied by cardiac catheterization and cineangiography. Ventriculograms were performed at rest and during a constant infusion of l-epinephrine (EPI) at 1-4 ,gg/min after a...

OBJECTIVE To re-examine the function of the urinary bladder in vivoas well as to determine the functional and biochemical characteristics of bladder muscarinic receptors in long-term alloxan-induced diabetes rats. METHODS Two-month-old male Wistar rats were injected with alloxan and the animals showing blood glucose levels >300mg/dL together with age-paired untreated animals were kept for 11 ...

Extracellular water (radiobromine), plasma volume (radioiodinated human serum albumin), and peripheral plasma renin activity were measured simultaneously in men with uncomplicated, untreated essential hypertension and in normal subjects. The ratio of plasma volume to interstitial fluid volume (PV/IF) was significantly lower in hypertensive patients (0.194 vs. 0.223, P < 0.001). This could not b...

Echocardiography was used to study left ventricular size and contraction in 128 patients with isolated aortic valve disease 45 patients with aortic stenosis, 25 with mixed aortic valve disease and 58 with aortic regurgitation. Left ventricular measurements included the end-diastolic internal dimension (LVIDd), mural thickness (PWTd), an index of circumferential myocardial contraction fractional...

The crystal structure of covellite has been studied under pressure up to 33 kbar based on single-crystal diffraction intensities collected with a four-circle diffractometer. The contraction of the unit cell takes place in such a way that the axial ratio e/a is kept nearIy constant, the cell volume at 1 bar being reduced by about 5% at 33 kbar. With the contraction of the Cu S bonds the sulfur-s...

Introduction. The once popular idea that changes in planetary volume play an important role in terrestrial orogeny and tectonics [ I ,2] was generally discarded with the acceptance of plate tectonics. It is nonetheless likely that the Earth has been steadily cooling over the last 3-4 billion years [e.g., 3,4], and the global contraction that accompanied such cooling would have led to a secular ...

Background. Muscles not only shorten during contraction to perform mechanical work, but they also bulge radially because of the isovolumetric constraint on muscle fibres. Muscle bulging may have important implications for muscle performance, however quantifying three-dimensional (3D) muscle shape changes in human muscle is problematic because of difficulties with sustaining contractions for the...