Human Mechanics
Mostrando 37-48 de 52 artigos, teses e dissertações.
-
37. Motions of the running horse and cheetah revisited: fundamental mechanics of the transverse and rotary gallop
Mammals use two distinct gallops referred to as the transverse (where landing and take-off are contralateral) and rotary (where landing and take-off are ipsilateral). These two gallops are used by a variety of mammals, but the transverse gallop is epitomized by the horse and the rotary gallop by the cheetah. In this paper, we argue that the fundamental diffe
The Royal Society.
-
38. An ex vivo model for the reperfusion of explanted human hearts.
A model of an ex vivo-reperfused human heart was developed by using a modified Langendorff coronary perfusion circuit. The technical and physiologic aspects of reestablishing myocardial contractility are described. Preliminary studies were conducted in animals. In the present study, we obtained 12 human hearts that had been arrested with cardioplegic solutio
-
39. Synchronous In Situ ATPase Activity, Mechanics, and Ca2+ Sensitivity of Human and Porcine Myocardium
Flash-frozen myocardium samples provide a valuable means of correlating clinical cardiomyopathies with abnormalities in sarcomeric contractile and biochemical parameters. We examined flash-frozen left-ventricle human cardiomyocyte bundles from healthy donors to determine control parameters for isometric tension (Po) development and Ca2+ sensitivity, while si
The Biophysical Society.
-
40. Animal models of asthma
Studies in animal models form the basis for much of our current understanding of the pathophysiology of asthma, and are central to the preclinical development of drug therapies. No animal model completely recapitulates all features of the human disease, however. Research has focused primarily on ways to generate allergic inflammation by sensitizing and chall
American Physiological Society.
-
41. Contraction of the human diaphragm during rapid postural adjustments.
1. The response of the diaphragm to the postural perturbation produced by rapid flexion of the shoulder to a visual stimulus was evaluated in standing subjects. Gastric, oesophageal and transdiaphragmatic pressures were measured together with intramuscular and oesophageal recordings of electromyographic activity (EMG) in the diaphragm. To assess the mechanic
-
42. A monoclonal antibody against the dynein IC1 peptide of sea urchin spermatozoa inhibits the motility of sea urchin, dinoflagellate, and human flagellar axonemes.
To investigate the role of axonemal components in the mechanics and regulation of flagellar movement, we have generated a series of monoclonal antibodies (mAb) against sea urchin (Lytechinus pictus) sperm axonemal proteins, selected for their ability to inhibit the motility of demembranated sperm models. One of these antibodies, mAb D1, recognizes an antigen
-
43. Mechanical and metabolic determinants of the preferred step width in human walking.
We studied the selection of preferred step width in human walking by measuring mechanical and metabolic costs as a function of experimentally manipulated step width (0.00-0.45L, as a fraction of leg length L). We estimated mechanical costs from individual limb external mechanical work and metabolic costs using open circuit respirometry. The mechanical and me
-
44. PCNA binding proteins in Drosophila melanogaster : the analysis of a conserved PCNA binding domain.
The eukaryotic polymerase processivity factor, PCNA, interacts with cell cycle regulatory proteins such as p21(WAF1/Cip1) and Gadd45, as well as with proteins involved in the mechanics of DNA repair and replication. A conserved PCNA-binding motif is found in a subset of PCNA-interacting proteins, including p21, suggesting that the regulation of these interac
-
45. Changes in pennation with joint angle and muscle torque: in vivo measurements in human brachialis muscle.
1. Estimates of pennation in human muscles are usually obtained from cadavers. In this study, pennation of human brachialis was measured in vivo using sonography. Effects of static and dynamic changes in elbow angle and torque were investigated. 2. Pennation was measured in eight subjects using an 80 mm, 5 MHz, linear-array ultrasound transducer to generate
-
46. The Use of Cardio-Green for Intraoperative Visualization of the Coronary Circulation: Evaluation of Myocardial Toxicity
Direct visualization of the extent and adequacy of the coronary blood flow distribution can be performed intraoperatively with an intracoronary injection of indocyanine green dye (Cardio-Green). Because Cardio-Green is potentially toxic to the myocardium, we studied its effects on the mechanical performance of cardiac muscle, using human right atrial trabecu
-
47. Contact pressures in the human hip joint measured in vivo.
The pressures on human articular cartilage have been measured in vivo. An instrumented femoral head prosthesis that telemeters interarticular pressure at 10 discrete locations 253 times per second was implanted in apposition to natural acetabular cartilage. Data were acquired during surgery, recovery, rehabilitation, and normal activity, for longer than 1 ye
-
48. Relating repair susceptibility of carcinogen-damaged DNA with structural distortion and thermodynamic stability
A key issue in the nucleotide excision repair (NER) of bulky carcinogen–DNA adducts is the ability of the NER machinery to recognize and repair certain adducts while failing to repair others. Unrepaired adducts can survive to cause mutations that initiate the carcinogenic process. Benzo[c]phenanthrene (B[c]Ph), a representative fjord region polycyclic arom
Oxford University Press.