Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 3 of 3

Full-Text Articles in Life Sciences

A Role For Fibronectin In The Development Of Beat In Chick Embryo Cardiogenesis, W. Kimryn Rathmell Jan 1991

A Role For Fibronectin In The Development Of Beat In Chick Embryo Cardiogenesis, W. Kimryn Rathmell

Presidential Scholars Theses (1990 – 2006)

Fibronectin is believed to play a directional role in the migration of precardiac mesodermal cells and m~y be involved in other aspects of cardiogenesis. In this study we investigated the role of fibronectin in the development development of heart beat by employing a chick precardiac explant culture system. Fibronectin is recognized by an integrin receptor molecule via an RGD amino acid sequence. Using a synthetic RGD peptide we have blocked the ability of any existing receptor molecules to interact with fibronectin in an attempt to break communication of the mesodermal cells with the extracellular environment. Explanted tissues treated with this …


Patterns Of Hydroxyproline Excretion In Ovariectomized And Estrogen Treated Rats, Gregg Horras Jan 1991

Patterns Of Hydroxyproline Excretion In Ovariectomized And Estrogen Treated Rats, Gregg Horras

Presidential Scholars Theses (1990 – 2006)

If nuclear binding sites for estrogens exist in bone cells, then the origin of estrogen-deficiency-induced osteopenia may be at the level of bone matrix protein synthesis. Since collagen is the most abundant protein in the bone matrix, and since hydroxyproline is an imino acid nearly exclusive to collagen, a monitoring of the metabolism of hydroxyproline in ovariectomized and estrogen treated rats may provide insight into the patterns of estrogen-deficiency-induced osteopenia. The purpose of our study was to test the hypothesis that ovariectomy will increase urinary hydroxyproline excretion in the rat and that this increase will be reversed by estrogen treatment …


Multivariate Analysis Of The Carex Brevior Group In Iowa, Scott C. Zager Jan 1991

Multivariate Analysis Of The Carex Brevior Group In Iowa, Scott C. Zager

Dissertations and Theses @ UNI

In Iowa, the most troublesome sedges to identify are Carex brevior, C. festucacea, C. molesta, C. normalis, C. tenera, and C. tenera var. echinodes. These taxa form the C. brevior group--part of an even larger aggregate of species associated with C. straminea. Their morphological features are indistinct and intergrade into one another. Botanists have had difficulty classifying members of this aggregate for nearly 200 years. Some authors have viewed the taxa as separate species, others as polymorphic forms of a single species. Much of the contention has centered upon the variation of taxonomic characters used to delimit and distinguish species. …