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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.
131

Follicular Development in Rabbits After Active Immunization to Testosterone

Armstrong, Walter Robert 11 1900 (has links)
<p>The role of testosterone in follicular development and ovulatIon has been investigated by immunizing female rabbits to testosterone-3-bovine serum albumin (T-3-BSA). The intent of this procedure was to render any endogenously produced testosterone inactive by means of its high affinity binding to specific antibody.</p> <p>In order to determine the time course of the effects of this procedure three groups of 12 - 6 control, 6 experimental - immaturely immunized rabbits were sacrificed at 5, 8 and 11 weeks after immunization. The effects observed at 11 weeks were compared with a group of 10 - 6 control, 4 experimental - maturely immunized rabbits sacrificed after the same length of immunization. In addition a group of 11 - 5 control, 6 experimental - immaturely immunized animals were mated to a proven male 14 weeks after immunization.</p> <p>Animals were boosted regularly and the antiserum titer followed weekly. Blood samples were taken weekly for the determination of FSH and LH levels and the total and percent bound testosterone and estradiol. After sacrifice the ovaries and uteri were removed for histology. Follicular development was examined and the maximum follicular diameter ≥ 1.0 mm and ≥ 1.5 mm was recorded. In mated animals the number of corpora lutea per ovary were counted.</p> <p>SignifIcant antiserum titers to testosterone were observed in all experimental rabbits by 5 weeks of immunization. Over the 14 weeks of the experiment values ranged from 1:700 to 1:52,000.</p> <p>In control rabbits serum testosterone values were less than 0.5 ng/ml while values in experimental rabbits rose steadily over the length of the experiment (group values ranged from 0.6 ± 0.1 ng/ml to 2.1 ± 0.9 ng/ml, 2.2 ± 0.7 ng/ml to 5.7 ± 0.8ng/ml and 4.4 ± 1.2 ng/ml to 6.8 ± 1.2 ng/ml at 5,8 and 11 weeks respectively). Testosterone binding in control animals remained in the 93% to 95% range throughout the experiment while in experimental animals testosterone binding increased significantly to approximately 99% at 5 weeks of immunization and remained constant thereafter.</p> <p>Estradiol values in control rabbits remained relatively constant throughout the ewperiment (group range: 50.7 ± 5.4 pg/ml to 81.8 ± 4.9 pg/ml). A consistent and significant increase in estradiol occurred in experimental animals (group values ranged from 69.5 ± 15.4 pg/ml to 88.5 ± 8.7 pg/ml, 74.5 ± 9.8 pg/ml to 118.5 ± 13.1 pg/ml and 81.6 ± 6.9 pg/ml to 157 ± 30.3 pg/ml at 5,8 and 11 weeks after immunization. Prior to immunization estradiol binding in experimental rabbits was not different from control values (range : 83% to 88%). There was a significant increase in estradiol binding by 5 weeks of immunization in the experimental groups (range: 89.4% to 94.5%). By 11 weeks estradiol binding increased to as much as 97.9%.</p> <p>Follicular development was abnormal in T-3-BSA immunized rabbits. The ovaries contained numerous large cystic and hemorrhagic follicles. At 8 weeks experimental ovaries contained more follicles ≥1.0 mm (27.2 ± 3.1 versus 15.3 ± 2.9, p < 0.01) and ≥1.5 mm (5.83 ± 1.7 versus 0.42 ± 0.2, p < 0.005). At 11 weeks there were more follicles ≥ 1.5 mm in both immature (5.0 ± 0.9 versus 0.92 ± 0.31, p < 0.001) and mature (7.25 ± 0.92 versus 4.17 ± 0.74, p < 0.05) experimental ovaries. Increased vascularization, some thecal cell hypertrophy, and marked interstitial cell hypertrophy were characteristic of the experimental ovaries. There was also a significant increase in the number of ovulations in the experimental rabbits (8.0 ± 2.1 versus 4.4 ± 1.9, p < 0.005).</p> <p>Immunization of female rabbits to testosterone is a useful tool for the study of hormone interactions in the regulation of follicular development and ovulation. In addition it may serve as a useful model for the study of the processes involved in the development of cystic ovaries.</p> / Master of Science (MS)
132

Do Simplified Drug Regimens Improve Compliance?

Reynolds, Laurence James 06 1900 (has links)
<p>A PROTOCOL FOR THE DESIGN OF A RANDOMIZED CLINICAL TRIAL IN A FAMILY PRACTICE SETTING IS DESCRIBED. THE TRIAL IS DESIGNED TO TEST IF TWICE A DAY (B.I.D.) ANTIBIOTICS PRODUCED BETTER COMPLIANCE THAN THE STANDARD FOUR TIMES A DAY (Q.I.D.) REGIMENS. THE DISEASE MODELS OF STREPTOCOCCAL PHARYNGITIS AND UNCOMPLICATED URINARY TRACT INFECTION ARE USED BECAUSE OF THEIR SIMILARITY AND BECAUSE THEY ARE COMMON IN THE FAMILY PRACTICE SETTING. COMPLIANCE MEASURES INCLUDE URINE ASSAY FOR ANTIBIOTIC PILL COUNTS AND DROP OUT RATES. COMPLIANCE WILL BE ANALYZED IN RELATIONSHIP TO THE TYPE OF REGIMEN, SIDE EFFECTS AND DISEASE OUTCOME.</p> / Master of Science (MS)
133

Parental origin of triploidy and trisomy in human miscarriages

Brennan, Barbara 09 1900 (has links)
Caspersson (1970) discovered that each chromosome pair has a characteristic banding pattern when chromosomes are stained with the fluorescent dye, quinacrine. With this dye there are certain chromosome regions which are polymorphic. These regions can be used as markers in the study of the inheritance of chromosome anomalies. The purpose of this study was to determine, using chromosome markers, the parental origin of the extra chromosomes found in triploid and D, G trisomic spontaneous abortuses. Polymorphisms in the chromosomes of parents of 15 triploid and 12 trisomic abortuses were compared with those of their abortus to determine which parent donated the extra chromosome(s). The distribution of the markers was used to determine whether the error occurred during meiosis I or meiosis II or, in the case of triploids, to distinguish between a meiotic error and dispermy. Of the 15 triploids examined, 7 were informative as to the origin of the extra set of chromosomes. In 3 of these there was failure to extrude to second polar body during oogenesis. In 3 other cases it was impossible to distinguish between an error during meiosis of spermatogenesis and dispermy. The other informative case definitely arose by dispermy. Mechanisms for the origin of triploidy were discussed, in particular, aging of gametes. Only 1 of the 12 trisomies examined was informative. This was a trisomy 22 in which the extra 22 was from the mother but it was not possible to distinguish between non-disjunction during meiosis I and meiosis II. Possible mechanisms for the production of trisomies were discussed including maternal irradiation, autoimmune processes, possible endocrine factors and drugs.</p> <p>A number of technical factors which influence the appearance of polymorphic regions were also discussed. / Master of Science (MS)
134

An Analysis of Laboratory Utilization in a Family Practice Unit

Alleyne, Curtis Brian 12 1900 (has links)
<p>This thesis is a report of the evaluation of laboratory utilization by a Family Practice Clinic. The evaluation covered the month of October, 1975. All encounter forms generated by patient visits in October were included in the study sample.</p> <p>The encounter form records whether a patient is new to the clinic, the nature of his visit, whether the visit is the first for a given problem or a follow-up visit, the diagnosis made at the visit, and any laboratory procedure ordered. These variables were combined in an instrument that determined the motive a physician might have for ordering a laboratory investigation.</p> <p>Three motives for ordering a laboratory procedure were defined, ie. casefinding, monitoring or diagnostic use. Tests requested were classified into the three categories. The classification instrument was validated and shown to be reliable. The data used from the encounter was shown to be only 50% reliable with unrecorded information being the major factor contributing to the unreliability of the data.</p> <p>The study showed that requests for laboratory procedure can be classified by the three motives for requesting them, ie. diagnosing, casefinding or monitoring. Sixty-one percent of the tests were used for diagnosis, 11% for casefinding and 28% for monitoring. Age, sex, nature of visit and the diagnosis of the patient were shown to be important variables in explaining the physician's use of the laboratory.</p> <p>The results indicate that the classification logic is an operational tool but in this study its validity has not been completely assured.</p> / Master of Science (MS)
135

The Association of Hemispheric Specialization and Cognitive Abilities with Regard to Sex, Hand Preferences and Birth Stress

MacFarlane, Joseph Robert 05 1900 (has links)
<p>The relationship of patterns of hemispheric specialization to verbal and non-verbal cognitive abilities were studied as well as the effects of birth stress on the etiology of left-handedness. Using verbal and non-verbal dichotic listening tests 28 right- and left-handed boys and girls with a mean age of 10.6 years, were assessed as being unilaterally or bilaterally organized for processing verbal and non-verbal material. The subjects were also assessed for verbal and non-verbal ability using standard intelligence tests. Birth records were obtained in order to assess whether birth stress resulted in perinatal anoxia, the agent for altering hand preference. It was found that:</p> <p>1) Boys may show a left ear effect for some nonverbal material but girls may not.</p> <p>2) Bilateral organization for processing non-verbal material is not necessarily correlated with poorer spatial ability in girls.</p> <p>3) The relationship of bilateral organization for processing verbal material with overall verbal ability were inconclusive.</p> <p>4) There is no evidence to indicate that birth stress and/or oxygen deficit are necessary for left-handedness to occur, since both right- and left-handers exhibit these factors to the same degree and at least some of the left-handers appear to show no evidence of birth stress at all.</p> / Master of Science (MS)
136

The Design of a System for the Evaluation of Comprehensive Primary Health Care in Rural Sierra Leone

Gage, Nathaniel George 09 1900 (has links)
<p>The purpose of this thesis is to describe a research design for evaluating the effectiveness of comprehensive primary health care in rural areas of Sierra Leone.</p> <p>Comprehensive primary health care, which is based on community participation within the framework of a policy of self-reliance and self-development is seen by many as the answer to solving the health problems of deveIoping countries.</p> <p>In setting the scene for evaluating the effectiveness of comprehensive primary health care in rural Sierra Leone, a description of the background of the country is given highlighting the major geographical, demographical and socioeconomical features. The state of health in the developing countries as a whole is also reviewed (Chapter 3).</p> <p>Chapter 4 explores the concept of comprehensive primary health care and reviews the operational aspects in the African context.</p> <p>In an attempt to establish some basis for the design of an effectiveness evaluation of comprehensive primary health care, the main methodologic issues in the presented setting are explored (Chapter 5).</p> <p>Having identified the main methodologic issues specific solutions and their justifications are proposed (Chapters 6,8,9).</p> <p>Finally, a specific protocol of the proposed research design is presented.</p> / Master of Science (MS)
137

A Design for a Randomized Controlled Trial to Assess the Effect of Clinical Audits on Ambulatory Care in Hospital Clinics

Baines, Johanna Cornelia 05 1900 (has links)
<p>A design is presented for a randomized controlled trial to answer the question: do audit procedures which hospitals are expected to carry out to meet requirements for hospital accreditation have a beneficial impact on ambulatory patient care in general and special clinics?</p> <p>Approximately 60 Ontario hospitals reporting general and special ambulatory care clinics to Statistics Canada will be invited to participate in the trial. Outpatient visits to potentially eligible clinics will be documented by hospital medical records staff and submitted to the Hospital Medical Records Institute. Nurse abstractors will identify indicator conditions from this outpatient census and categorically score patient management over three periods of time: a pre-audit period before intervention occurs, a first audit period and a second audit period.</p> <p>Hospitals stratified according to size and function will have been randomly allocated to three groups. Indicator conditions relevant to caseloads and casemix will be assigned to eligible clinics.</p> <p>Groups I and II will both have indicator conditions introduced to clinic staff prior to the first audit period. Only Group I will receive feedback about their performance in the first audit period.</p> <p>After the second audit period it should be possible to separate the effects of audit awareness (Groups I and II), of feedback (Group I) and of extraneous factors (Group III) on patient management. Results will be expressed as mean clinic scores.</p> <p>If improved performances occur in Groups I and II, the usefulness of current accreditation criteria will have been demonstrated. If no change in performance occurs and the indicator condition criteria approach is accepted as being valid in this setting, then it may be appropriate to consider new approaches to accreditation.</p> / Master of Science (MS)
138

Manual Motor Functions in Developmental Dysphasia

Archer, Lynda A. 08 1900 (has links)
<p>The term developmental dysphasia refers to children who fail to develop speech and language at the normal time and in the normal manner although they do not have a primary emotional disturbance nor a physical handicap, and are not globally mentally retarded or deaf. Empirical investigations of the disorder have studied auditory perception, visual perception, linguistic and articulatory function, attention and orientation, scholastic performance and reading ability, and hemispheric specialization. With the exception of the studies of auditory perception and hemispheric specialization little promising data have been generated. Investigators of auditory perception have suggested that the language disorder in developmental dysphasia may be attributable to an impairment in auditory perceptual processing. Data from studies of the hemispheric specialization of development dysphasics suggest that dysphasics may have aberrant hemispheric specialization.</p> <p>Neuropsychological investigations of adult language disturbance, i.e. adult aphasia, have concluded that the left hemisphere is specialized for certain kinds of motor function, speech and language being one such function, and that it is an impairment in certain kinds of motor function which is crucial to speech and language disturbances, and not an impairment in linguistic processing or symbolic function as has been suggested by many researchers.</p> <p>This research studied developmental dysphasia with the hypothesis that since this disorder involves speech and language difficulties perhaps it might be related to a deficit in certain aspects of motor functioning, specifically, the organization and execution of fine (as contrasted with gross) actions. This motor performance was also considered within the context of hemispheric specialization since: i) previous work has indicated atypical patterns of hemispheric specialization in developmental dysphasics, ii) motor functions appear to he lateralized and iii) the motor tasks lend themselves to being performed by each hand separately.</p> <p>Ten developmental dysphasics were selected according to strict criteria and were administered seven measures of motor ability, several of these being nonstandardized tests designed specifically for this research. Five of these were lateralized tests (i.e., it was required that the task be performed by each hand separately), while the remaining two were nonlateralized measures. The lateralized measures were a repetitive tapping task, the Annett peg moving task, a children's sequence box task, a hand posture imitation task and a hand movement imitation task. The Illinois Test of Psycholinguistic Abilities manual expression test and an oral movement imitation task were the non-lateralized measures. It was found that the dysphasics performed more poorly than their matched control subjects on the hand posture imitation task, the hand movement imitation task and the ITPA manual expression test. On the repetitive tapping, Annett peg moving, children's sequence box and oral movement imitation tasks the dysphasics performed as well as their control subjects: A laterality effect was not observed on any of these measures for either the normal subjects or the dysphasics.</p> <p>These results were interpreted to mean that developmental dysphasics have a deficit in certain aspects of manual motor function. It is proposed that this is a specific and higher order deficit, not observed in all types of motor function. Moreover, it is suggested that it is a deficit in the initiation, organization and execution of motor behavior and not in the perception. Given that a laterality effect was not observed for any of the measures, no definitive conclusions were possible regarding the hemispheric specialization of developmental dysphasics.</p> <p>Data from linguistic measures administered in addition to those used for subject selection, further confirmed the receptive language deficit in the developmental dysphasics and also indicated difficuIties in the processing of written language. These latter data were interpreted to mean that developmental dysphasia may represent a language disorder which encompasses all forms of language behavior, not just oral language reception and production.</p> / Master of Science (MS)
139

Dynamic and stable regulation of pyruvate dehydrogenase in human skeletal muscle

LeBlanc, Paul-Jean 02 1900 (has links)
<p>The mechanisms regulating the rate-determining enzyme of carbohydrate oxidation, pyruvate dehydrogenase (PDH), were examined in human skeletal muscle at rest and during exercise in response to acute respiratory alkalosis and short- and long-term aerobic training. Voluntary hyperventilation-induced respiratory alkalosis (R-Alk) delayed PDH activation during the transition from rest to submaximal exercise. A mismatch between pyruvate production and its oxidation in R-Alk resulted in a 35% higher lactate accumulation. These effects were not seen during steady state exercise. The results from this study suggest that respiratory alkalosis may play an important role in lactate accumulation during the transition from rest to exercise in acute hypoxic conditions, but that other factors mediate lactate accumulation during steady state exercise. Short-term aerobic training did not alter resting skeletal muscle total PDH (PDHt) and PDH kinase (PDK) activities, or their respective protein expressions compared to pre-training. In contrast, long-term aerobic training (Post) compared to pre-training (Pre) resulted in a 31% increased total PDHt activity, partially due to a 1.3 fold increased protein expression of a PDH subunit, PDHE 1 α. Despite the increased PDHt activity post-training, there was an approximate 37% attenuated activation of PDH Post after 15 min of exercise at the same absolute submaximal workload compared to Pre. PDK demonstrated a 2 fold increased activity Post, partially attributed to a 1.3 fold increased PDK2 isoform protein expression. The training-induced increased PDK2 isoform expression, pyruvate-sensitive PDK isoform, coincided with an attenuated skeletal muscle pyruvate content Post during submaximal exercise at the same absolute workload. The results of these findings suggest that aerobically trained human skeletal muscle has an increased maximal capacity to utilize carbohydrates, evident by increased PDHt, but increased metabolic control sensitivity to pyruvate during submaximal exercise through increased contribution of PDK2 to total PDK activity.</p> / Doctor of Philosophy (PhD)
140

The Design of a Cost-Effectiveness Analysis Within a Concurrent Randomized Clinical Trial of the Hamilton-Wentworth Chronic Home Care Programme

Caulfield, Ann Wall Patricia 08 1900 (has links)
<p>The economic analysis described in this thesis is designed to compare two alternate approaches to post-hospital treatment for a specified group of chronically ill patients who are aged 65 and over and eligible for Home Care at the point of discharge from acute hospitals. Relative costs and health effects will be compared between the Hamilton-Wentworth are programme and the "no programme" situation or the usual of treatment without Home Care, using a cost-effectiveness model. Data will be collected from the Home Care group (experimental) and the No Home Care group (control) in a concurrent randomized clinical trial of the Home Care programme for the specified patients of interest. Costs will be measured as described herein. Health effects of interest will be physical function, social function and morale.</p> <p>The completed results of the study will provide needed information about the magnitude and distribution of costs in each programme alternative for this specific group of patients in Hamilton-Wentworth and about the relation of costs to health effects. The analysis will have relevance to the Hamilton-Wentworth programme and to the Ontario Ministry of Health, as well as planners of similar programmes for similar groups of patients and the patients themselves. The data should add to the growing body of knowledge about the economics of Home Care programmes.</p> <p>The methods developed here for measuring cost in a variety of services and for collection of health service utiIization data could be applied to other studies of similar community-based, multiservice programmes in relation to either specific patient groups or the overall programme impact. The models used for analysis and health effects within the context of a randomized trial should be applicable to other health care evaluations.</p> / Master of Science (MS)

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