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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

COAGULATION AND FIBRINOLYTIC RESPONSE TO EXERCISE, COLD, AND EXERCISE WITH PRIOR COOLING

Unknown Date (has links)
Ten male student volunteers (mean age, 27.1 years) participated in this investigation to determine if exercise and cold stress could differentially effect coagulation and fibrinolysis. Euglobulin lysis times (ELT) and partial thromboplastin times (PTT) were used to assess fibrinolytic activity and coagulability, respectively. Cold and neutral environmental conditions were established at 5(DEGREES)C and 28(DEGREES)C. Exercise consisted of pedaling a bicycle ergometer at 300 kgm(.)min('-1) for five minutes followed by ten minutes at 900 kgm(.)min('-1). The testing schedule was as follows: / rest exercise / Session A (Cold): PC CR CE / rest exercise / Session B (Neutral): PN NR NE / Time (mins) 60 15 / ELT, PTT, and hematocrit (HCT) was assessed at PC, pretest-cold; CR, cold-rest; CE, cold-exercise; PN, pretest-neutral; NR, neutral- rest; and NE, neutral-exercise. Mean weighted skin temperatures (T(,sk)) and rectal temperatures (T(,re)) were assessed at 15-minute(' ) intervals throughout.(' )T(,sk) dropped continuously during cold exposure (CR, CE) but was relatively unaffected under neutral conditions. T(,re) response to cold was more complex, exhibiting an initial increase followed by a decrease with continued exposure. T(,re) increased in response to exercise at 28(DEGREES)C but exhibited no change at 5(DEGREES)C. ELT was reduced to 74, 62, and 44% of pretest values for CR, NE, and CE, respectively. No difference was found to exist between groups for PTT. HCT was increased to 107, 107, and 111% of pre-test values for CR, NE, and CE, respectively. These data suggest that coagulation and fibrinolysis may be affected differentially in response to exercise, a result that speaks in favor of exercise-induced fibrinolysis as a prophylaxis for atherosclerosis. / Source: Dissertation Abstracts International, Volume: 43-02, Section: B, page: 0350. / Thesis (Ph.D.)--The Florida State University, 1982.
2

OVARIAN CONTROL OF GONADOTROPIN SECRETION IN THE RAT

Unknown Date (has links)
The control of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) secretion by a hypothalamic releasing peptide (GnRH) and the modulation of FSH and LH secretion by ovarian steroids has been demonstrated. There is increasing evidence that another ovarian factor, gonadostatin (GnS) may also contribute significantly to the control of gonadotropin (FSH and LH) secretion. GnS appears to contribute to the negative feedback on gonadotropin secretion, particularly FSH. The function of a separate factor in the negative feedback control of FSH may be to control, ultimately the number of follicles that develop and ovulate. / Examination of ovarian steroid feedback at physiological concentrations, demonstrated that steroids alone do not provide complete feedback control of FSH secretion. GnS is thought to be the additional factor that completes the negative feedback control of FSH release. Administration of GnS in the form of porcine follicular fluid (pFF) together with physiological levels of estradiol resulted in basal levels of serum FSH. / Steroids exert positive as well as negative feedback control of gonadotropin secretion. Basal and surge release of LH could be fully controlled with estradiol and progesterone alone (replaced to mimic normal changing levels). In contrast, neither basal nor surge secretion of FSH were controlled with steroids. The addition of GnS to a cyclic steroid regimen provided complete control of FSH secretion (both basal and surge) and suggests that GnS may play a significant role in the control of FSH secretion throughout the estrous cycle. / The response of dispersed pituitary cells to estradiol (with or without GnRH) is an enhancement of gonadotropin secretion, in contrast to suppression of gonadotropin secretion seen in vivo. The use of a perfused pituitary cell system allowed the cells to be pulsed with GnRH thereby producing the conditions thought to occur in vivo. Under conditions of pulsed GnRH stimulation the secretion of gonadotropins was dramatically suppressed by gonadostatin and to a small extent by estradiol. / These studies have suggested that gonadostatin may play a significant role in the negative feedback of FSH and to a lesser extent LH secretion. / Source: Dissertation Abstracts International, Volume: 42-12, Section: B, page: 4701. / Thesis (Ph.D.)--The Florida State University, 1982.
3

PROTEIN UTILIZATION DURING SUBMAXIMAL EXERCISE IN TRAINED WOMEN AND MEN

Unknown Date (has links)
The contribution of protein as a substrate source during exercise has recently been suggested to be 5-20% instead of 1-2%. Isolated studies have observed female and male responses but never simultaneously in the study. It was the purpose of this study to observe protein utilization in women and men during the same experimental stress. Five trained women and men, who were matched by their aerobic capacity (42-50 ml/kg/min) underwent a discontinuous VO(,2)max test to determine 70% and 60% VO(,2)max values. The subjects returned to the lab for a resting, baseline session and two exercise series consisting of a one-hour (1 h) 70% VO(,2)max muscle glycogen depletion ride and a 1h 60% VO(,2)max data collection ride. Subjects alternated between a carbohydrate loaded diet (CHO-l) and a carbohydrate depleted diet (CHO-d). Urine samples were collected pre-post exercise. Serum samples were obtained pre-, mid-, and post-exercise. Sweat was collected in a gauze pad on the upper arm, chest, and abdomen during three 15-minute intervals. Urea nitrogen in the urine, serum, and sweat was used as an indicator of protein utilization and 3-methylhistidine as an indicator of skeletal muscle degradation. There were no significant gender differences with respect to urea nitrogen and 3-methylhistidine. The CHO-d diet significantly increased the concentration of urea nitrogen in the serum (p < .05) and the urea nitrogen excretion rate in the sweat and the urine (p < .05) in comparison with CHO-l and baseline. Three-methylhistidine excretion in the urine was not significantly altered by the diets. The established range of protein contribution in this study was between .80-1.36%. The results of this study indicate that women and men respond similarly with respect to protein contribution to energy production when introduced to the same relative exercise stress. / Source: Dissertation Abstracts International, Volume: 45-04, Section: B, page: 1123. / Thesis (Ph.D.)--The Florida State University, 1984.
4

BIOCHEMICAL AND PHYSIOLOGICAL RESPONSES OF THE DIABETIC RAT HEART TO INDUCED MYOCARDIAL ISCHEMIA

Unknown Date (has links)
The purpose of this investigation was to determine the biochemical and physiological responses of the ischemic diabetic rat heart as left ventricular peak systolic pressure declined to 75% and 50% of baseline. In addition, this study assessed the influence of iodoacetate in non-diabetic and diabetic animals. The results show that diabetic and iodoacetate-treated hearts reached the selected declines in pressure significantly faster (p < .05) than non-diabetic hearts. Significantly lower (p < .05) myocardial ATP levels were found in the diabetic and iodoacetate-treated rat hearts indicating that the relative lack of anaerobically-derived ATP hastened the reduction in pressure. Myocardial glycogen utilization was significantly greater (p < .05) in diabetic hearts. However, intramuscular lactate indicative of anaerobic ATP production remained relatively lower than non-diabetic values. The results strongly suggest that the relative decrease in anaerobically-derived ATP is responsible for the rapid decline in left ventricular peak systolic pressure associated with the diabetic rat heart. / Source: Dissertation Abstracts International, Volume: 44-06, Section: B, page: 1732. / Thesis (Ph.D.)--The Florida State University, 1983.
5

THE SUBCELLULAR DISTRIBUTION, METABOLISM AND COMPOSITION OF AXONALLY TRANSPORTED GLYCOCONJUGATES

Unknown Date (has links)
This study investigated the distribution and composition of glycoconjugates axonally transported to subcellular fractions of goldfish optic tectum, specifically the SPM, SV and soluble fractions. In addition this study also assessed the effectiveness of using different solvents for the extraction of intact axonally transported glycoconjugates. / The subcellular distribution of radioactivity in the goldfish optic tectum 12 hrs and 24 hrs postintraocular injection of ('35)S-sulfate or ('3)H-fucose, respectively, indicated that the RSA of both SV and SPM was greater than those of other membranous fractions. A small portion of transported label was associated with the soluble fraction. At 36 hrs PIO injection of ('35)SO(,4), the RSA of the SV and SPM increased by 18% and 9% respectively, whereas the RSA of the soluble fraction decreased by 16%. / Compositional analysis of the SPM glycoconjugates demonstrated that fucosylated molecules had a broad MW distribution mainly below 100k daltons, whereas sulfated molecules had MWs > 100k daltons. In contrast to SPM, transported sulfated and fucosylated GC of the SV fraction demonstrated an MW distribution primarily below 100k daltons. / Anion exchange chromatography resulted in the separation of 3 populations of transported soluble GC. Those molecules eluting with increasing ionic strength from the anion exchange column showed a progressive increase in MW as seen by gel filtration. The late eluting peak of highly acidic molecules contained in addition to sulfated glycopeptides all of the soluble glycosaminoglycans indicating the presence of transport labeled proteoglycans. / To determine conditions which would lead to solubilization of membrane-affiliated AT GC, pooled optic tecta were sequentially homogenized in different solvents 12 hrs PIO injection of ('35)SO(,4). Approximately 20% of the recovered transported label was soluble in buffered sucrose, 12% was extracted with sucrose containing 1.0 M NaCl, 34% was extracted with 4 M guanidine and 11% remained unextracted. The sucrose and salt extracted mainly GP while guanidine extracts and unextracted residue were enriched in PGs. / Source: Dissertation Abstracts International, Volume: 44-09, Section: B, page: 2672. / Thesis (Ph.D.)--The Florida State University, 1983.
6

PHYSIOLOGICAL AND BIOCHEMICAL CHARACTERIZATION OF A PROLACTIN INHIBITORY FACTOR OF UTERINE ORIGIN (PITUITARY GLAND, CELL CULTURE, RAT)

Unknown Date (has links)
These studies involve the identification, partial purification and physiological characterization of a prolactin inhibitory activity (PIA) of uterine origin. A dispersed anterior pituitary cell culture system was validated and employed as a bioassay for the PIA. This bioassay coupled with hormone radioimmunoassays and protein assays allowed for the assessment of the amount and potency of the PIA. Initial experiments demonstrated that prolactin (PRL) release from pituitary cells exposed to uterine extract for a 24 h period is inhibited in a dose-dependent manner. Accompanying this inhibition is a dose-dependent increase in intracellular PRL. Hormonal specificity of PIA is suggested by the fact that neither follicle-stimulating hormone nor luteinizing hormone were affected by uterine extract. Estimation of PIA in the uterus and similarly prepared extracts of gut, cardiac muscle and diaphragm reveal that PIA is restricted to uterine tissue. Pharmacological studies using specific receptor blockers indicate that the PIA is neither dopamine nor GABA. PIA is neither proteolytic nor cytotoxic since incubation with standard rat PRL did not decrease the amount of immunoreactive PRL and following uterine extract treatment pituitary cells secrete elevated levels of PRL. / Isolation and culturing of uterine epithelial, stromal and myometrial cells reveal that the PIA is confined to secretions of the epithelial layer. PIA is greater in sera from ovariectomized rats than in sera from ovariectomized-hysterectomized rats. Decrease of PIA in the circulation of hysterectomized rats suggests that the activity is hormonal in nature. / Isolation and purification of PIA involved acid extraction, heat fractionation, gel permeation chromatography, isocratic and reverse-phase high pressure liquid chromatography. These methods followed by amino acid analysis indicate that the PIA is a 63 amino acid polypeptide with an apparent MW of approximately 6900. / In summary, the uterus may function as an endocrine organ by secreting into circulation a non-dopaminergic, non-GABAergic low MW peptide which specifically suppresses PRL release from the anterior pituitary gland. / Source: Dissertation Abstracts International, Volume: 46-01, Section: B, page: 0077. / Thesis (Ph.D.)--The Florida State University, 1984.
7

THE EFFECT OF ENDURANCE TRAINING AND TAPER TRAINING ON THE ACTOMYOSIN ATPASE ACTIVITY OF RAT SOLEUS MUSCLE

Unknown Date (has links)
The effects of endurance treadmill training and taper training on the actomyosin ATPace activity of rat soleus muscle was studied. Taper training was defined as a linear regression reduction of time of training by 5% per day after steady state training had been established. Thirty-two male Sprague-Dawley rats of the Wistar strain were randomly assigned to one of four groups: (SC) sedentary control, (RC) running control, (TI) 7 day taper trained, or (TII) 14 day taper trained. The steady state exercise protocol consisted of two hours of treadmill running up a 12(DEGREES) slope at 27.5 m/min. for 11 weeks. At the end of the 7-day taper phase, TI animals were running for only 65% of the time of RC animals. At the end of the 14-day taper phase, TII animals were running for only 30% of the time of RC animals. Biochemical analysis of the soleus actomyosin ATPase activity followed procedures set by Baldwin, Winder, and Holloszy (1975). Results indicated a statistically significant (p < 0.05) increase in Mg++ activated actomyosin ATPase activity for RC (42%), TI (43%), and TII (38%) compared with SC values. Both TI and TII exercise protocols provided enough stimulus to maintain an enhanced actomyosin ATPase activity, and values were not different from RC values. A taper effect was then defined as the maintenance of the previously adapted muscle actomyosin ATPase activity while greatly reducing the amount of exercise stimulus applied to that muscle. / Source: Dissertation Abstracts International, Volume: 43-12, Section: B, page: 3864. / Thesis (Ph.D.)--The Florida State University, 1983.
8

REGULATION OF THE MATING-INDUCED RELEASE OF PROLACTIN BY THE DORSOMEDIAL-VENTROMEDIAL NUCLEI OF THE HYPOTHALAMUS AND THE MEDIAL PREOPTIC AREA (NEUROENDOCRINE)

Unknown Date (has links)
This project sought to describe the roles of the dorsomedial-ventromedial nuclei (DMN-VMN) and the medial preoptic area (MPOA) in the regulation of mating-induced prolactin secretion in the female rat. Stimulation of the uterine cervix as in mating, initiates the recurring secretion of daily nocturnal and diurnal surges of prolactin. The DMN-VMN is an important regulatory area for the prolactin surges and operates as a stimulatory center. Electrical stimulation of this area mimics the effects of cervical stimulation inducing both surges of prolactin. The DMN-VMN is essential for induction of the diurnal surge. Electrolytic lesions of the DMN-VMN prevent initiation of diurnal surges by cervical stimulation without affecting nocturnal surge secretion. The regulatory functions of this area are sexually specific and sexually reversible. DMN-VMN stimulation has no effect on prolactin release in normal adult males rates but can trigger nocturnal surges in neonatally feminized male rats. The MPOA also has multiple regulatory functions, serving as an inhibitory center for the nocturnal surge and as both a stimulatory and inhibitory center for the diurnal surge. In conscious, cervically stimulated females electrical stimulation of the MPOA inhibits release of nocturnal or diurnal surges. In anesthetized, non-cervically stimulated females stimulation of the MPOA induces a diurnal surge. Also, electrolytic lesions of the MPOA terminate the diurnal surges in cervically stimulated rats. The prolactin inhibitory role of the MPOA is not sex specific. Lesions of the MPOA trigger nocturnal surges in females and small nocturnal and diurnal surges in males. MPOA stimulation inhibits the nocturnal surge but can not induce a diurnal surge in females bearing lesions of the DMN-VMN. This indicates that the MPOA functions independently of the DMN-VMN for nocturnal surge regulation while these two areas function together for regulation of the diurnal surge. / Source: Dissertation Abstracts International, Volume: 45-09, Section: B, page: 2827. / Thesis (Ph.D.)--The Florida State University, 1984.
9

ELECTROPHYSIOLOGICAL RESPONSES FROM THE OLFACTORY SYSTEM OF THE AMERICAN EEL

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 40-10, Section: B, page: 4681. / Thesis (Ph.D.)--The Florida State University, 1979.
10

THE ONTOGENY OF TASTE AND FLAVOR PREFERENCE IN PUPPIES

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 40-10, Section: B, page: 4672. / Thesis (Ph.D.)--The Florida State University, 1979.

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