Anatomy Commons^™

The Coronary Distribution Zone : Mathematical Modelling Of The Left Ventricular Epicardial Surface For Area Calculation, Three-Dimensional Rotaton And Display, S. Matts E. Sjölander

Loma Linda University Electronic Theses, Dissertations & Projects

A computer model of the left ventricular (LV) epicardial surface was developed from Jang’s truncated ellipsoidal model, which has a minor to major axis ratio of 6:10. The model was applied in calculating the area of a segment of the myocardium, jeopardized by an impending occlusion of its associated artery. The endangered segment of the LV muscle was also visualized in different projections by rotations in three space and graphical displays simulating the three dimensions.

The area formula for the surface of the ideal model , a truncated prolate spheroid, was derived and used in producing maps for manual calculations …

Transpiration And Co2 Fixation Of Selected Desert Shrubs As Related To Soil-Water Potential, S. B. Clark, J. Letey Jr., O. R. Lunt, A. Wallace, G. E. Kleinkopf, E. M. Romney

Great Basin Naturalist Memoirs

In desert plants, transpiration rates decreased before photosynthetic rates when plants were entering a period of water stress. This may have adaptive consequences. A difference of -5 bars in the soil-moisture potential had considerable importance in reducing the rate of transpiration. In Helianthus annuus L. (sunflower) the photosynthetic rate decreased before the transpiration rate in contrast to Great Basin-Mojave Desert plants, and the changes occurred with a -1 bar difference in soil-moisture potential. Morphological changes in three desert plant species [Artemisia tridentata Nutt., Ambrosia dumosa (Gray) Payne, Larrea tridentata (Ses. Moc. ex DC) Cov.] as the soil-moisture potential decreased …

Parent Material Which Produces Saline Outcrops As A Factor In Differential Distribution Of Perennial Plants In The Northern Mojave Desert, A. Wallace, E. M. Romney, R. A. Wood, A. A. El-Ghonemy, S. A. Bamberg

Great Basin Naturalist Memoirs

An area of 0.46 km² divided into six zones in the northern Mojave Desert transitional with the Great Basin Desert has been studied. Diversity is high among the perennial plant species within the 0.46 km² area. Common species for the two deserts that are present in the area studied are Atriplex confertifolia (Torr. & Frem.) S.Wats., Ceratoides lanata (Pursh) J. T. Howell, Grayia spinosa (Hook.) Moq., Ephedra nevadensis S. Wats. Some other species present include Lycium andersonii A. Gray, Lycium pallidum Miers, Ambrosia dumosa (A. Gray) Payne., Larrea tridentata (Sesse & Moc. ex DC) Cov., Acamptopappus shockleyi A. …

Mineral Compostition Of Atriplex Hymenelytra Growing In The Northern Mojave Desert, A. Wallace, E. M. Romney, R. B. Hunter, J. E. Kinnear, G. V. Alexander

Great Basin Naturalist Memoirs

Fifty samples of Atriplex hymenelytra (Torr.) S. Wats, were collected from several different locations in southern Nevada and California to test variability in mineral composition. Only Na, V, P. Ca, Mg, Mn, and Sr in the samples appeared to represent a uniform population resulting in normal curves for frequency distribution. Even so, about 40 percent of the variance for these elements was due to location. All elements differed enough with location so that no element really represented a uniform population. The coefficient of variation for most elements was over 40 percent and one was over 100 percent. The proportion of …

End Matter, Vol. 4, Index

Great Basin Naturalist Memoirs

No abstract provided.

Full Issue, Vol. 4

Great Basin Naturalist Memoirs

No abstract provided.

End Matter, Vol. 4

Great Basin Naturalist Memoirs

No abstract provided.

Front Matter, Vol. 4

Great Basin Naturalist Memoirs

No abstract provided.

A Light And Electron Microscopic Study Of Visual Neurons In The Medulla Externa Of The Crab Hemigrapsus Nudus, Yu Cheng Liao

Loma Linda University Electronic Theses, Dissertations & Projects

The decapod crustacean with a relatively well-defined visual system have contributed significantly to our understanding of visual neuron morphology and physiology. The general morphology of the optic lobes of several decapods were initially described by Parker (1897) and Hanstrom (1924). In the past few years, several light and electron microscope studies have been made on the lamina ganglionaris: the first optic ganglion, of the lobster (Hamori and Horridge, 1966a); the crayfish (Hafner, 1974; Nassel, 1976a), and the crab (Stowe et al., 1977; Rafuse et al., in preparation). As yet, no adequate description has been made of the visual neurons in …

The Effects Of Prostaglandin Synthesis Inhibition On The Regulation Of Blood Pressure In The Rat, David J. Pollock

Masters Theses

No abstract provided.

The Association Of Semen Factors With The Recovery Of Ureaplasma Urealyticum, Rebecca D. Cintron

Biological Sciences Theses & Dissertations

Fifty-six semen samples from males under examination for suspected subfertility were examined to determine if alterations in specific semen parameters could be associated with the presence or absence or Ureaplasma urealvticum. Twenty-seven (48.2%) of the specimens cultured positive for U· urealyticum in U9B urease broth and A-7 differential agar. Both positive and negative specimens have a normal average motility rating. Overall sperm counts (millions per ml) were slightly lower and ejaculate volumes higher in U. urealvticum positive samples. Morphological abnormalicies were not found more frequently in U. urealyticum positive samples. No statistically significant difference between seminal parameters of U. …

Effect Of Experimental Glomerulonephritis On The Cells In Canine Renal Lymph, Sandra L. Garber

Dissertations

No abstract provided.

The Effect Of Prostaglandin F₋B2₋Sa And Prostaglandin E₋B2₋S Upon The Endometrium Of The Mature OöPhorectomized Rat, Marilyn Mavis Miller

Dissertations

No abstract provided.

Connectivity Of The Inferior Olivary Complex In Normal And Neonatally Hemicerebellectomized Rats, Rand S. Swenson

Dissertations

No abstract provided.

Activation Of Long Descending Propriospinal Neurons In Cat Spinal Cord, Robert J. Adams, Robert D. Skinner, Ronald S. Remmel

Journal of the Arkansas Academy of Science

Isolated mammalian spinal cord has been shown capable of generating locomotor activity. Propriospinal systems assumed to coordinate fore- and hindlimb activity are poorly understood. This study characterizes the long descending propriospinal (LDP) neurons in terms of the location of the somas and their peripheral inputs by direct neuronal recording. Anatomical studies using axonal retrograde transport of horseradish peroxidase from the lumbar to the cervical spinal cord as a tracer first described these neurons. Two hundred and thirty-one LDP neurons were identified in electrophysiological experiments. Of these, 123 responded to natural stimulation, and about 50% of the others were activated only …

Study Of The Anatomy Of The Alimentary Canal Of Brochymena Quadripustulata (Hemiptera:Pentatomidae), Dan T. Barber, Lynita M. Cooksey, David W. Abell

Journal of the Arkansas Academy of Science

An anatomical study of the alimentary canal and associated salivary apparatus was conducted for the pentatomid, Brochymena quadripustulata. The esophagus, ventriculus, pylorus, rectum, principal salivary glands and ducts are described and illustrated. Described structures of Brochymena quadripustulata are compared with various species of pentatomids and other hemipterans.

Connections Of The Mesencephalic Locomotor Region (Mlr) In The Cat, E. Garcia-Rill, Robert D. Skinner, S. A. Gilmore

Journal of the Arkansas Academy of Science

The cat entopeduncular nucleus (EN), which is the main output of the basal ganglia, is known to project to the mesencephalic tegmentum. We have been able to elicit antidromic responses in single EN neurons from the region of the mesencephalic locomotor region (MLR), then transect (precollicular-postmamillary) the brainstem and elicit rhythmic movements of the limbs by stimulation of the same site in the same animal. Injections of the fluorescent dye 2,4 diamidino phenylindole 2 HCL (DAPI) into this area induces retrograde labeling of cell bodies in EN and motor cortex. Injections of a tritiated amino acid (leucine) into the motor …

Time And Life: Applications Of Modern Chronobiology, Lawrence E. Scheving, John E. Pauly

Journal of the Arkansas Academy of Science

Chronobiology is that branch of science which objectively quantifies and explores mechanisms of biological time structure. It is an integrating discipline that impacts on all forms of life. When physiological functions are plotted along a time scale, they appear as regularly repetitive wave forms with means, amplitudes, phasing and periods. In nature these rhythms are found to have many frequencies, from a fraction of a second (ultradian) to a year or more (infradian or circannual); and those with periods of about one day (circadian) have been explored extensively. Examples of several circadian rhythms are given for experimental animals and man. …

How We Look: Studies Of Oculomotor-System Neural Connections, Ronald S. Remmel, Robert D. Skinner

Journal of the Arkansas Academy of Science

The neural connections of the reticular formation (RF) with the vestibular nuclei (8V) and the ascending medial longitudinal fasciculus (MLF) were studied, because many neurons in these structures carry eye-movement and head-movement (vestibular) signals and are only one or two synaptic connections removed from eye motorneurons. We used stimulating electrodes placed in specific brainstem structures and a single-neuron recording microelectrode in anesthetized or decerebrate cats. Connections were determined when the neurons were excited either forwards (orthodromically) or backwards (antidromically) by a shock. Four classes of neurons were studied. One neuronal class in the pontine RF projects axons into the ascending …

Investigation Of A Factor Released By Neoplastic Cells Which Produces A Chemokinetic Response In Activated Macrophages, Richard Durelle Lane

Theses and Dissertations

The increase in rate of random migration (chemokinesis) of C. parvum activated macrophages in media conditioned by Lewis Lung (LL) carcinoma cells was attributed to a trypsin sensitive, heat stable, high molecular weight factor released from the membrane of the tumor cells.

A capillary tube assay was developed to expediently monitor the chemokinetic activity of macrophages incubated in whole and fractionated media. The capillary tube assay was found to be capable of detecting both chemokinetic and chemotactic (directional movement) factors present in the test media. Statistical analysis revealed the capillary tube assay provided reproducible data both within and between experiments. …