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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.
51

Characterization of Nocturnal Fish Assemblages on Vessel and Natural Reefs of Broward County, Florida, USA

Anderson, Rachel Lynn 06 October 2009 (has links)
Approximately 65 vessel reefs have been deployed intentionally in Broward County, Florida since 1982. The purpose of these deployments was to enhance fish stocks for recreational fisheries and sport divers. The other main goal was to reduce pressure on heavily exploited natural reefs. Several studies have been conducted at both artificial and natural reef sites in the area; however, none of these have focused on nocturnal fish assemblages (Ferro et al., 2005; Arena et al., 2007). The goal of our study was to characterize nocturnal fish assemblages on vessel and natural reefs in Broward County. This data, in addition to the existing diurnal data, will provide a more comprehensive understanding of fish assemblage structure on artificial and natural reefs. Comparisons among vessel and natural nocturnal fish assemblages and previous diurnal studies were made. Abundance was greater on diurnal natural and vessel reefs when compared to nocturnal. Abundance was also greater on nocturnal vessel reefs than nocturnal natural reefs. The twilight period on vessel reefs was characterized by high abundance of piscivores and a significantly greater abundance of grunts than during the nocturnal period. The abundance of grunts supports their movement during this time to surrounding sand flats to feed. The vertical relief of the vessel reefs seemed to appeal to an abundance of pelagic fishes as well as planktivores. Distinctly different fish assemblages were seen between nocturnal natural and vessel reefs, as well as between diurnal and nocturnal natural reefs and vessel reefs. Fisheries-important fishes were more abundant during the day, but also more abundant on vessel reefs than natural reefs. Although vessel reefs do not mimic the natural reefs studied or support the same fish assemblages, they are providing habitat for diverse nocturnal fish assemblages.
52

Factors influencing nightly activity of deer mice (Peromyscus maniculatus) in tallgrass prairie

Rehmeier, Ryan L. January 1900 (has links)
Doctor of Philosophy / Department of Biology / Donald W. Kaufman / Glennis A. Kaufman / Little is known about nightly activity patterns of nocturnal small mammals under natural conditions, and how these activity patterns might be affected by photoperiod, season, and sex, age, and reproductive status of individuals. The main objectives of this research were: 1) to find an appropriate method for marking individual deer mice (Peromyscus maniculatus) so that their activity could be monitored remotely; 2) to design a portable activity-monitoring system to investigate temporal patterns of shelter use by deer mice under natural conditions; 3) to determine the influence of environmental conditions such as photoperiod and season on nightly activity of deer mice; and 4) to compare effects of demographic or physiological factors such as sex, age, and reproductive status on nightly activity of deer mice at artificial burrows in tallgrass prairie. In general, commencement of activity was correlated positively with timing of sunset, and time of retirement to the burrow was correlated positively with sunrise. Among adults, males first emerged from the burrow earlier and made more trips of shorter duration in a night than did females, although total duration of trips was similar. Return visits and subsequent stays typically were shorter for males than females, but total time spent in the burrow and retirement time relative to sunrise were similar for both sexes. Young deer mice emerged significantly later, made more trips of shorter duration, spent less total time outside, and retired to their burrow earlier than adults. Reproductive females emerged later, made fewer trips of generally longer duration, and spent shorter total amounts of time away from the burrow each night than non-reproductive females. Return visits of reproductive females were of longer duration than non-reproductives, but total time spent inside and time of retirement for the night did not differ relative to reproductive status. From parturition through lactation, activity of females showed a number of directional trends. Results suggest that under natural conditions, activity patterns of deer mice are highly variable but responsive to both the changing physical environment and internal conditions related to sex-specific maximization of fitness.
53

Behavioural ecology and conservation biology of ground pangolins Smutsia temminckii in the Kalahari Desert

Pietersen, Darren William January 2013 (has links)
Ground pangolins Smutsia temminckii are inconspicuous, mainly nocturnal mammals that occur at low population densities. As a result, there is scant information available on the ecology and physiology of this species. To date the handful of studies focussing on this species were centred in the mesic eastern regions of its range, with no attention being given to ecological and biological traits in arid environments. To address these data shortfalls, a study was undertaken in the Kalahari Desert in northwestern South Africa. Very High Frequency (VHF) transmitters or Global Positioning System (GPS) loggers were fitted to 16 ground pangolins and their ecology and physiology studied over a period of three years. Throughout its range the ground pangolin is increasingly endangered, predominantly due to anthropogenic threats. Previous studies have identified threats facing this species, but very few of these studies included quantitative data as to the extent of these threats. The present study suggests that the main threats to ground pangolins in southern Africa are electrocution on electrified fences, the traditional medicine trade, habitat loss, road mortalities and capture in gin traps. Although accidental poisoning has previously been viewed as a threat, a review of the available literature suggests that this is not the case and that these views stemmed from two isolated incidents of captive animals. Electrocutions probably pose the greatest threat to ground pangolins, with mortality rates of one pangolin per 11 km of electrified fence per year recorded during this study. Home range sizes of this arid-zone population are comparable to the home range sizes recorded in mesic populations. Study animals in the Kalahari had Minimum Convex Polygon (MCP) home range values of 10.0 ± 8.9 km² SD for adults and 7.1 ± 1.1 km² SD for juveniles, in comparison to the 0.17 – 23.38 km² MCP in Zimbabwe and 1.3 – 7.9 km2 MCP in mesic north-eastern South Africa. These results are surprising as arid-zone animals usually have larger home ranges than do their mesic counterparts. It is hypothesised that this discrepancy is due to the fact that ground pangolins in the Kalahari are on average 25 – 30 % smaller than their mesic counterparts. This smaller body size means that individuals require a smaller home range to meet their dietary requirements, which could be counteracting the trend of arid-zone individuals requiring larger home ranges. This research also found ground pangolins to be more active during the day in winter and nearly entirely nocturnal during summer. These changes in photoperiodicity are likely driven by adaptations to the extreme climatic conditions present at the study site rather than predation pressure or changes in food resources, although the latter may be playing a role as well. By being diurnal in winter, individuals avoid the extremely cold night-time temperatures, thus saving energy that would otherwise be spent on maintaining their body temperature. By contrast, becoming nocturnal in summer allows them to avoid the extreme daytime temperatures, thus conserving water. The results of this study reiterate previous findings that ground pangolins are entirely myrmecophagous and highly selective of the species that they eat. Study animals were recorded feeding on only four ant and two termite species, representing 7.5 % and 50 % of the total species richness of each of these families. This is similar to previous research in mesic savannahs where five ant one termite species constituted 97 % of the ground pangolin’s diet. No seasonal differences in prey selection were observed, although the species consumed did depend on the habitats that were available to individual ground pangolins. This study is the first to investigate the core body temperature (Tb) of a free-ranging pangolin. These data indicated that Tb fluctuated cyclically between 32 – 35 °C and reflected the activity periods of the animal, peaking when the animal was active. When the individual was inactive, Tb steadily decreased, suggesting that it used daily heterothermy to cope with the low food availability in this unpredictable environment. In summary, ecological parameters between arid and mesic ground pangolin populations are similar in some respects, but divergent in others. Arid-zone populations are smaller overall and show a higher degree of diurnal activity. Despite this smaller body size, home range values appear to be similar between arid and mesic populations. Although the prey species eaten by ground pangolins in the Kalahari differ from prey species in eastern South Africa and Zimbabwe, they belonged to the same genera and were of similar morphology and ecology. The core body temperature results confirm findings from previous captive studies that pangolin body temperatures are lower than those of other eutherian mammals of a similar size. Furthermore, these data indicate that core body temperature is a lot more variable than previously believed, and thus warrants further study. Overall ground pangolin densities in the Kalahari appear to be double those in eastern South Africa and Zimbabwe, although it is unclear whether this is genuine or whether it is an artefact of individuals being easier to locate in the Kalahari. This study also confirmed that electrocutions are probably the greatest threat to this species, and new threats such as accidental capture in gin traps and road mortalities have also come to light. / Dissertation (MSc)--University of Pretoria, 2013. / gm2014 / Zoology and Entomology / unrestricted
54

Thermal Management of Combined Photovoltaic and Geothermal Systems

Almoatham, Sulaiman 15 May 2023 (has links)
No description available.
55

Utilizing Acoustic Recorders to Investigate the Migratory Behavior of Some Sparrow and Warbler Species along the Ohio Coast of Lake Erie.

Gesicki, David V. 10 December 2013 (has links)
No description available.
56

Morning Flight Behavior of Nocturnally Migrating Birds in Relation to a Geographic Obstacle

Tuck, Paul T. 14 November 2017 (has links)
No description available.
57

Under-recognized complications in patients with paroxysmal nocturnal haemoglobinuria: raised pulmonary pressure and reduced right ventricular function

Hill, A., Spasford, R.J., Scally, Andy J., Kelly, R.J., Richards, S.J., Khurisgara, G., Sivananthan, M.U., Hillmen, P. January 2012 (has links)
Pulmonary hypertension is becoming a recognized complication of the hereditary and acquired haemolytic anaemias, associated with a poor prognosis. Recently we reported that patients with paroxysmal nocturnal haemoglobinuria (PNH) have high levels of N-terminal pro-brain natriuretic peptide (NT-proBNP), a biomarker associated with both right and left ventricular dysfunction and cardiac dysfunction. In the current study we evaluated a cohort of patients (N = 29) with haemolytic PNH for elevated pulmonary artery systolic pressure and cardiac function by Doppler-echocardiography. Of the 29 patients, eight were further studied using cardiac magnetic resonance imaging (MRI), as well as two additional patients (number of patients studied using cardiac MRI = 10). Plasma from the first cohort (N = 29) demonstrated intravascular haemolysis associated with a 12-fold increase in median nitric oxide (NO) consumption when compared with healthy volunteers (P < 0·001). Doppler echocardiography demonstrated normal left ventricular function and elevated pulmonary artery systolic pressure in 41% of patients. Cardiac MRI from the second cohort (N = 10) demonstrated depressed right ventricular function in 80% of PNH patients tested, and 60% had findings suggestive of subclinical small pulmonary emboli. Together, these data suggest a high prevalence of haemolysis-associated NO scavenging, Doppler-estimated systolic pulmonary hypertension, and depressed right ventricular function in patients with PNH.
58

Improving the efficiency and accuracy of nocturnal bird Surveys through equipment selection and partial automation

Lazarevic, Ljubica January 2010 (has links)
Birds are a key environmental asset and this is recognised through comprehensive legislation and policy ensuring their protection and conservation. Many species are active at night and surveys are required to understand the implications of proposed developments such as towers and reduce possible conflicts with these structures. Night vision devices are commonly used in nocturnal surveys, either to scope an area for bird numbers and activity, or in remotely sensing an area to determine potential risk. This thesis explores some practical and theoretical approaches that can improve the accuracy, confidence and efficiency of nocturnal bird surveillance. As image intensifiers and thermal imagers have operational differences, each device has associated strengths and limitations. Empirical work established that image intensifiers are best used for species identification of birds against the ground or vegetation. Thermal imagers perform best in detection tasks and monitoring bird airspace usage. The typically used approach of viewing bird survey video from remote sensing in its entirety is a slow, inaccurate and inefficient approach. Accuracy can be significantly improved by viewing the survey video at half the playback speed. Motion detection efficiency and accuracy can be greatly improved through the use of adaptive background subtraction and cumulative image differencing. An experienced ornithologist uses bird flight style and wing oscillations to identify bird species. Changes in wing oscillations can be represented in a single inter-frame similarity matrix through area-based differencing. Bird species classification can then be automated using singular value decomposition to reduce the matrices to one-dimensional vectors for training a feed-forward neural network.
59

Análise da microarquitetura do sono (padrão alternante cíclico) na polissonografia de crianças com enurese noturna monossintomática / Sleep microstructure analysis (Cyclic Alternating Pattern) in children with monosymptomatic nocturnal enuresis

Soster, Leticia Maria Santoro Franco Azevedo 08 December 2015 (has links)
Introdução: A enurese noturna (EN) é considerada como a eliminação de urina no período noturno, de forma involuntária, em indivíduos com cinco ou mais anos de idade em pelo menos duas noites no mês até todas as noites. EN pode ser do tipo monossintomática, quando ocorre na ausência de outros sintomas, ou não monossintomática, na presença de sintomas de vesicais diurnos. Apesar de historicamente conhecida com uma desordem psiquiátrica, a EN monossintomática está incluída na Classificação Internacional dos Transtornos de 2012 como uma parassonia podendo ocorrer em qualquer fase do sono, porém predominantemente no sono não REM. Está comumente associada a hiperatividade vesical, produção excessiva de urina e falha em acordar após o enchimento vesical. Apesar de ocorrer no sono, a avaliação do sono pelos padrões usuais falhou em encontrar justificativa para este processo patológico. A análise da microestrutura do sono é uma ferramenta mais refinada e precisa que pode auxiliar na busca do mecanismo neurofisiológico que justifica este processo. Objetivo: Analisar os padrões de microarquitetura de sono atrvés do Padrão alternante Cíclico (CAP) nas crianças com EN monossintomática para melhor compreensão das bases neurofisiológicas da EN. Metodologia: Trinta e seis crianças sendo, 22 enuréticos e 14 controles com idade variando entre sete e 17 anos de idade, que satisfizeram os critérios de inclusão, foram submetidas a triagem clínica e laboratorial, avaliados quanto aos aspectos do sono, com uso de diários de sono, das escalas de Berlin, Sleep Scale for Children (SDSC) e Escala de Sonolência de Epworth e posteriormente submetidos ao de estudo polissonográfico completo de noite inteira, com a avaliação do CAP. Resultados: As escalas de sonolência e de Berlin não evidenciaram anormalidades, o SDSC evidenciou apneia em 11/22 (50%), hiperidrose em 2/22 (9%) e transtorno da transição vigília-sono, do despertar e do início e manutenção de sono em 1/22 (4,5%) cada. A análise da estrutura do sono mostrou maiores números de despertares (p < 0,001) e de sono N2 (p=0,0025) além de maior quantidade de sono N3 (p < 0,0001) do que nos controles. A microestrutura do sono evidenciou aumento da fase A1 (p=0,05), porém de forma mais contundente, redução das fases A2 e A3 (p < 0,0001), mesmo com a taxa de CAP igual à dos controles normais.Conclusão: Crianças com EN possuem sono com comorbidades (avaliado pelo SDSC) e menos fases CAP A2 e A3, significando uma redução no seu mecanismo de despertar e que ainda não havia sido demonstrado num estudo de PSG com análise das variáveis comuns. Este é o primeiro estudo que demonstra tal fenômeno / Introduction: Nocturnal enuresis (NE) is defined as the lack of nocturnal urine control, in individuals with five or more years old for at least two nights in a month, but up to every night. EN can be monosymptomatic (ENM), when it occurs in the absence of other symptoms or non monosymptomatic in the presence of diurnal renal symptoms. Although historically known as a psychiatric disorder, ENM is included in the International Classification of Sleep Disorders 2012 as a parasomnia. It can occur at any sleep stage but predominantly in non-REM sleep. EN is commonly associated to bladder hyperactivity, excessive urine production and/or failure to wake up after bladder filling. Despite the occurrence in sleep, standard sleep evaluation has failed to find abnormalities. The analysis of sleep microstructure is a refined and more accurate tool that can help find the neurophysiological mechanism underlying this process. Purpose: To evaluate sleep microarchitecture through Clyclic Altenating Pattern (CAP) analysis in children with monosymptomatic NE and provide a better understanding of the neurophysiological basis of EN. Methods: After IRB approval, 36 children, 22 with NE and 14 controls aged between seven and 17 years old who met the inclusion criteria were submitted to clinical and laboratory screening, evaluated for aspects of sleep, using sleep logs, Berlin Questionnaire (BQ), Sleep Scale for Children (SDSC) and Epworth Sleepiness Scale (ESS) and submitted to a full polysomnographic study, with evaluation of CAP. Results: ESS and BQ evidenced no abnormalities, the SDSC showed mild sleep apnea in 11/22 (50%), hyperhidrosis in 2/22 (9%) and disorder of the sleep-wake transition, awakening and initiation and maintenance sleep in 1/22 (4.5%) each. Analysis of sleep macrostructure showed higher numbers of awakenings (p < 0.001) and N2 sleep (p = 0.0025) as well as greater amount of sleep N3 (p < 0.0001) when compared to controls. Sleep microstructure showed an increase in A1 phase (p = 0.05), and reduction of A2 and A3 (p < 0.0001). CAP rate was the same for both enuretic and controls. Conclusion: Children with EN may present sleep comorbidities (measured by SDSC) and less A2 and A3 CAP phases, meaning a reduction in its wake regulation. This is the first study to acknowledge this phenomenon
60

Bladder brain dialogue: 膀胱功能改變對腦幹功能影響的實驗研究 / 膀胱功能改變對腦幹功能影響的實驗研究 / CUHK electronic theses & dissertations collection / Bladder brain dialogue: Pang guang gong neng gai bian dui nao gan gong neng ying xiang de shi yan yan jiu / Pang guang gong neng gai bian dui nao gan gong neng ying xiang de shi yan yan jiu

January 2014 (has links)
Background and Purpose: Primary nocturnal enuresis (PNE) is a heterogeneous disorder with various underlying pathophysiological mechanisms. Results of our recent studies focused on the relationship of bladder function, sleep and brain function demonstrated a simultaneous occurrence of bladder and brain dysfunction in children with severe refractory PNE. We therefore proposed to use an animal model with altered bladder function to evaluate if abnormalities in bladder function induce functional derangement in brainstem micturition centers and/or sleep-arousal centers. / Materials and methods: In general, the study was divided in to 6 parts. Male Wistar rats (~ 1.5 months) were used for the study. / Study I: Establishment of animal model —— Male Wistar rats (200-220 g) underwent either Sham surgery or surgical reduction of bladder volume (RBV). Animals were used for further Cystometry, EEG, MRS and Cognitive function studies 4-5 weeks postoperatively. / Study II: Conventional Fill Cystometry (CFC) to evaluate bladder functional changes in response to surgical bladder volume reduction —— Twenty-four rats (RBV=12, SHAM 12) were used for the study. CFC was performed under conscious condition for evaluating the functional changes in response to surgical bladder capacity reduction. / Study III: Radiotelemetered EEG study to assess the impact of bladder dysfunction on sleep architecture and cortical arousals in rats —— Twenty-four rats (RBV=12, SHAM 12) were used for the study. Radiotelemeters were implanted in both groups 4 weeks post-operatively. The EEG biopotential and bladder pressure were monitored for 48 hours. Sleep architecture and cortical arousals were then evaluated manually. / Study IV: Evaluation of cognitive function following surgical bladder volume reduction —— Ninety eight rats (RBV=50, SHAM =48) were used for the study. / Morris Water Maze task: A circular plastic translucent pool half-filled with 26 ± 2ºC water, was used in the Morris Animals were given 9 consecutive training (2/day) sessions of Morris Water Maze (MWM) at 4 weeks postoperatively. / 8-arm Radial Maze: Food pellets were randomly placed inside each arm of the maze and the rats were allowed to explore the maze freely for 5 minutes. The rat was allowed to explore the maze for 5 minutes. Total time spent in each arm, total distance traveled in the maze was recorded. / Study V: Magnetic Resonance Spectroscopy to detect functional changes in brain in response to bladder dysfunction elicited by surgical bladder volume reduction —— Proton magnetic resonance spectroscopy was employed to examine brain metabolic changes in 24 rats (RBV=12, SHAM=12). Single voxel 1 H MRS experiments were performed using a 7 T MRI scanner. MR spectra were then processed using the jMRUI software. / Phase VI: Enzyme -linked immunosorbent assay for the assessment of associated changes in neurotransmitters —— Animals were euthanized after MRS study and brain samples were collected. Serotonin and dopamine levels were assessed in 10 mg of tissue extracts from brainstem and cortex, with ELISA kits. / Results: Study I: Bladder reduction surgery did not affect the increase in body weight post -operatively. Average body weight of the RBV and the sham groups were 340.2 ± 47.2 g and 340.5 ± 67.9 g respectively at 4 weeks post operatively. / Study II: Compared to sham group, the maximum cystometric capacity in animals with RBV was remarkably reduced at week 4 (0.78 ± 0.12 ml vs. 1.46 ± 0.22 ml, RBV vs. Sham respectively; p<0.005). Moreover, maximum detrusor pressure during voiding was significantly increased in RBV group at week 4 post operatively (32.4± 2.14 vs.23.27±1.2 5 cm H2O, RBV vs. Sham respectively). / Study III: Light non-repaid eye movement sleep occurred significantly more in RBV rats compared to sham group (61.8% vs 35%). Deep sleep and rapid eye movement sleep occurred significantly less in RBV group compared to that of sham group (30.7% vs 53.4%). / Study IV: Results showed that the RBV group used a significantly longer latency to locate the platform compared to Sham group (24.4s vs 17.19s, RBV vs. Sham respectively, p<0.001).. Moreover, significantly more animals from the RBV group could not complete the visit of the 8 arms of radial maze than that of the sham group. / Study V: Seven metabolites were detected and quantified. The results demonstrated significant changes in the lactate (Lac) metabolism in some specific regions of rat brain. At 4 weeks post - operatively, level of lactate significantly decreased in the hippocampus (43%, P<0.001) cingulate and retrosplenial cortex (29%, p<0.05) of RBV rats compared to that of sham rats. / Study VI: Results demonstrated a significant increase in Serotonin level in the brainstem of RBV rats compared to that of SHAM rats (23.726 + 0.88 ng/ml vs. 1.88 + 0.302 ng/ml). Dopamine levels decreased significantly in brainstem samples of RBV group compared to sham group (2.85 + 0.10 ng/ml vs. 6.85 + 0.84 ng/ml). / Conclusion: Surgical bladder volume reduction of bladder capacity can induce functional changes in the central nervous system. An alteration of the sleep architecture occurred in response to surgical reduction of bladder volume in rats, suggesting that there exists a potential for central consequences of bladder dysfunction. Bladder disorder chronically altered brain energy metabolism. Furthermore, bladder disorder altered the central neurotransmission in the brainstem and cortex. The finding of bladder dysfunction induced significant impairments in cognitive function in RBV rats, suggesting that the alteration in brain energy metabolism may contribute to the behavioral and attention problems, impaired learning and cognitive performance. / 研究背景: 原發性夜間遺尿症(PNE)是一種異質性疾病,涉及多種潛在的病理生理機制。我們最近的研究主要集中在膀胱功能,睡眠和腦功能的關係,結果顯示膀胱和腦功能障礙同時出現在患有嚴重難治性的PNE的兒童。因此,我們建議採用一種已改變膀胱功能的動物模型來評估膀胱功能異常會否引起腦幹排尿中心和/或睡眠 - 覺醒中心的功能紊亂 / 研究工具和方法: 研究被分成6個部分。雄性Wistar大鼠(約1.5個月)被用於研究。 / 研究I: 動物模型的建立 —— 雄性Wistar大鼠(200-220克),會先接受假手術或手術降低膀胱容量(RBV)。手術後4至5週,動物會進行進一步的膀胱測壓,腦電圖,MRS和認知功能研究。 / 研究II: 以常規填充膀胱測壓(CFC)評估減少膀胱容量手術對膀胱功能的變化 —— 二十四隻大鼠(RBV=12,對照=12)被用於研究。 CFC是用以評估在有意識的條件下,膀胱因膀胱容量減少的手術而引起的功能變化。 / 研究III: Radiotelemetered腦電圖研究,以評估在大鼠膀胱功能失調對睡眠結構和皮質覺醒的影響 —— 二十四隻大鼠(RBV=12,對照=12)被用於研究。膀胱容量減少的手術4週後,Radiotelemeters被植入在兩個組別的大鼠,並監測其腦電生物電勢和膀胱內壓48小時,然後手動評估睡眠結構和皮層覺醒。。 / 研究IV: 評估在膀胱容量減少的手術後對認知功能的影響 —— 103個大鼠(RBV=56,對照= =47)被用於研究。 / Morris水迷宮任務: 一個圓形的塑料半透明池盛載半滿的水,溫度介乎26 - ±2℃,手術4週後,該池被用在莫里斯動物進行連續9次Morris水迷宮(MWM)培訓(每天2次)。 / 八臂迷宮: 食物顆粒被隨機放置在迷宮的每個臂內,大鼠可以自由地探索迷宮5分鐘。大鼠被允許探索迷宮5分鐘。在每個手臂所用的總時間,以及在迷宮行走的總距離都會被記錄。 / 研究V: 以磁共振波譜檢測膀胱容量減少的手術所引起的膀胱功能障礙對腦功能的改變 —— 以質子磁共振波譜研究24隻大鼠腦內的代謝變化(RBV=12,對照==12)。以7 T MRI掃描儀進行磁共振波譜實驗,然後使用jMRUI軟件處理MR譜。 / 第六期: 以酶聯免疫吸附測定法評估神經遞質的相關變化 —— 動物在進行MRS研究後實施安樂死,並收集其腦樣品。從腦幹和皮層提取10毫克組織提取物,使用ELISA試劑盒,以評估羥色胺和多巴胺水平。 / 結果: 研究I: 膀胱容量減少手術並沒有影響體重增加。手術4週後,利巴韋林和對照實驗組的平均體重分別為340.2±47.2克和340.5±67.9克。 / 研究II: 相比起對照實驗組的動物,RBV組的最大膀胱容量顯著降低(0. 0.78 ± 0.12毫升對1.46±0.22毫升),排尿頻率顯著增加(2.53±0.30 對.0.53±0.05/hr)。此外,排尿時最大逼尿肌壓力亦顯著升高(32.0.8±2.19 比.20.37±1.2 5厘米水分子) / 研究III: 相比起對照實驗組的動物,光非快速動眼期睡眠顯著地較多發生於RBV大鼠身上(61.8%對35.6%),深層睡眠和快速動眼期睡眠顯著地較少發生在RBV組(32.3%對52.8%) / 研究IV: 結果表明,RBV組使用了顯著較長的時間來定位平台(24.4s vs. vs.17.19s)。而且,在RBV組,顯著地較多動物無法完成行走8臂的放射狀迷宮。 / 研究V: 進行檢測和定量七種代謝物。結果顯示乳酸(LAC)代謝在大鼠大腦的某些特定區域出現顯著變化。在手術4週後,相比起對照實驗組的動物,RBV組大鼠在海馬體(43%,P <0.001),扣帶和夾肌皮質(29%,P <0.05)的乳酸水平均顯著減少。 / 研究VI: 結果顯示RBV大鼠腦幹的血清素水平較對照實驗組的顯著增加(23.726+0.88納克/毫升與1.88±0.302ng/ml)。RBV大鼠腦幹的多巴胺水平則較對照實驗組的顯著下降(2.850.10納克/毫升與6.85+0.84毫微克/毫升)。 / 結論: 外科膀胱容量減少可誘導中樞神經系統的功能變化。以外科手術減少膀胱容量的大鼠亦引起睡眠結構改變,這顯示膀胱功能障礙對中樞有潛在影響。膀胱疾病長期改變大腦的能量代謝。此外,膀胱疾病亦改變了在腦幹和大腦皮層的中樞神經遞質傳遞。研究發現膀胱功能障礙顯著地損害RBV大鼠的認知功能,顯示改變大腦的能量代謝亦可導致行為和專注力的問題,從而損害學習和認知能力。 / Yeung, Chung Kwong. / Thesis Ph.D. Chinese University of Hong Kong 2014. / Includes bibliographical references (leaves 199-230). / Abstracts also in Chinese. / Title from PDF title page (viewed on 14, September, 2016). / Yeung, Chung Kwong. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only.

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