• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 126
  • 114
  • 53
  • 22
  • 22
  • 14
  • 5
  • 5
  • 4
  • 4
  • 2
  • 2
  • 1
  • 1
  • 1
  • Tagged with
  • 450
  • 40
  • 39
  • 32
  • 30
  • 27
  • 26
  • 26
  • 26
  • 26
  • 26
  • 24
  • 24
  • 24
  • 22
  • 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.
11

Effective Management of Extremity Cancers Using Cisplatin and Etoposide in Isolated Limb Perfusions

Roseman, James M. 01 January 1987 (has links)
Four cases of extremity cancers received effective management with cisplatin and etoposide via isolated limb perfusion. They demonstrated minimal, if any, soft tissue damage. This result counters the theory that a caustic response is a prerequisite for successful therapy. This characteristic allows for simultaneous surgical resection with regional, isolated limb perfusion of potent cytotoxic agents without increased morbidity from tissue necrosis, a common consequence of previously used drugs. There is no apparent affect on wound healing, even in cases involving extensive, radical operative procedures.
12

An assessment of the clinical relevance of minimal residual disease in childhood acute lymphoblastic leukaemia

Goulden, Nicholas John January 1998 (has links)
No description available.
13

A molecular study of DiGeorge syndrome

Atif, Uzma January 1997 (has links)
No description available.
14

Effects of X-irradiation on Potassium Flux in Isolated Nerves

Ramsey, Christian Norman 08 1900 (has links)
The purpose of this study, therefore, was threefold in nature: (1) to determine the effects of x-irradiation on the influx and efflux of potassium in compound nerve fibers (2) to attempt to relate the radiation-induced changes in electrical activity with potassium flux and (3) to use the information obtained to gain insight into the possible cellular site (s) of radiation insult to compound nerves.
15

Účinky vybraných flavonoidů na izolovaných aortálních kroužcích potkana / The effects of some flavonoids on isolated rat aortic rings

Fišrová, Martina January 2019 (has links)
Charles University Faculty of Pharmacy in Hradec Kralove Department of Farmacology & Toxikology Student: Martina Fišrová Supervisor: PharmDr. Marie Vopršalová, CSc. Title of diploma thesis: The effects of some flavonoids on isolated rat aortic rings Flavonoids are secondary plant metabolites that are profusely represented in nature. They are known for their wide range of effects and many of them have beneficial effects on the human body. Above all, they have anti-bacterial and anti-inflammatory properties and effects on cardiovascular system - they cause vasodilation. The aim of this diploma thesis was to investigate vasorelaxation effects of selected flavonoids from the group of flavonolignans - 2,3-dehydrosilybin A (DHS-A), 2,3-dehydrosilybin B (DHS-B) and metabolites, which are components of the silymarin complex found in the plant Silybum marianum (Asteraceae). The vasorelaxation potential of tested substances was verified in ex vivo conditions on isolated rat aortic rings. The effect of increasing doses of individual substances in precontracted aortic rings with intact endothelium was measured. From the measured values, the DRC curves were constructed and EC50 values were determined. The analysis of the results shows, that DHS-A (EC50 = 30,1 mol/l) had the most signifiant activity. Its...
16

Gluconeogenesis and Ammonia Production in the Isolated Perfused Rat Kidney : The Effect of Starvation, Acidosis and Diabetic Ketosis

SAKAMOTO, NOBUO, TSUCHIDA, ISAMU, SANO, TAKAHISA, KAWAMURA, TAKAHIKO, NISHIDA, TOMOATSU, SAKAKIBARA, FUMIHIKO, GOTO, ENJIRO 03 1900 (has links)
No description available.
17

Nonlinear seismic response of Mexican bridges with base isolation accounting for soil structure interaction effects

Olmos Navarrete, Bertha Alejandra 15 May 2009 (has links)
A parametric analysis of typical base isolated bridges was conducted. The bridges were located in different soil types and were subjected to three different earthquakes (recorded on soft and medium soils). The work had two main objectives: to asses the effects of the nonlinear behavior of the isolation pads of the bridges on the seismic responses (accelerations, displacements, and pier seismic forces), and to study combined effects of base isolation and inertial interaction due to the presence of flexible foundations. The analytical models used for the study were selected on the basis of initial evaluation of different models proposed in the literature to represent a bridge structure and to evaluate the isolation pads’ nonlinear behavior. The bridges studied were developed with a three-dimensional model. After completing the studies, 2 degree of freedom models were used to investigate more general trends of the inertial SSI effects for the base isolated bridges. The results of the work show the efficiency of base isolation pads in improving the seismic performance of bridges in most cases. They suggest that the inertial SSI effects will not be generally important for bridge foundations designed with a factor of safety of 3, with more than one line of piles in either direction since they will be very stiff foundations. But they also showed that for slender piers it is important to carefully evaluate the translations on top of the piers due to the rocking effects of the foundation.
18

Lipid metabolism in the isolated perfused ruminant liver

Hagyard, Stanley Benton, 1938- January 1969 (has links)
No description available.
19

Aneuploidy and DNA fragmentation in morphologically abnormal sperm

Tang, Steven Siu Yan 11 1900 (has links)
Introduction: Intracytoplasmic sperm injection (ICSI) has been a successful assisted reproductive technique for men with severe male-factor infertility. However, ICSI requires the subjective selection of normal looking sperm, which does not preclude the transmission of genetically abnormal sperm. Correlation between abnormal sperm morphology and chromosomal abnormalities has been suggested but not been conclusive and less is known about the connection between sperm morphology and DNA integrity. Sperm morphology will be evaluated on its ability to identify the level of chromosomal abnormalities or fragmented DNA in sperm. To further focus this investigation on sperm morphology, men with infertility isolated to abnormal sperm morphology (isolated teratozoopsermia) are examined. Materials and Methods: Sperm from isolated teratozoopsermic men (n=10) were analysed by fluorescent in situ hybridization (FISH) and terminal dUTP nick-end labelling (TUNEL) assays to determine the level of aneuploidy and DNA fragmentation, respectively. These results were also compared to that of sperm from control men (n=9) of proven fertility and normal seminal parameters. Results: Sperm from teratozoospermic men, compared to control men, had higher rates of total chromosomal abnormality (5.90±3.74% vs. 2.35±0.87%, P=0.0128), total aneuploidy (4.90±2.82% vs. 1.99±0.65%, P=0.0087), and chromosome 13 disomy (0.77±0.50% vs. 0.20±0.14%, P=0.0046). In control samples, incidence of tapered heads associated with supernumerary chromosomal abnormalities (rs=0.9747, P=0.0167). In teratozoospermic samples, incidence of amorphous heads associated to chromosome 13 disomy and sex chromosome aneuploidy (rs=0.6391, P= 0.0466; rs=0.8049, P=0.0050, respectively). Tail abnormalities were associated with chromosomal abnormalities (bent tail-disomy 13: rs=0.7939, P=0.0061; 2-tailed-disomy 13: rs=0.8193, P=0.0037; 2-tailed-supernumerary chromosomal abnormalities: rs=0.7534, P=0.0119). Levels of DNA fragmented sperm were higher in teratozoospermic men than control men (60.28±21.40% vs. 32.40±17.20%, P=0.0121). DNA fragmentation in sperm positively correlated with the incidence of sperm with bent necks in control samples (rs=0.8571, P=0.0238) and round headed sperm in teratozoospermic samples (rs=0.6727, P=0.0390). Conclusions: Sperm of isolated teratozoospermic men have elevated rates of chromosomal abnormalities and DNA fragmentation compared to that of fertile controls. Specific abnormal sperm morphology can be correlated wiht chromosomal abnormalities and level of DNA fragmentation in sperm and this may prove useful in sperm selection for ICSI when applied to isolated teratozoospermic patients.
20

Performance Analysis of Isolated Intersection Traffic Signals

Yin, Kai 16 December 2013 (has links)
This dissertation analyzes two unsolved problems to fulfill the gap in the literature: (1). What is the vehicle delay and intersection capacity considering left-turn traffic at a pre-timed signal? (2). What are the mean and variance of delay to vehicles at a vehicle-actuated signal? The first part of this research evaluates the intersection performance in terms of capacity and delay at an isolated pre-timed signal intersection. Despite of a large body of literature on pre-timed signals, few work has examined the interactions be- tween left-turn and through vehicles. Usually a protected left-turn signal phase, before (leading) or after (lagging) through signal, is applied to a signalized inter- section when the traffic demand is relatively high. A common problem for leading left-turn operation is the blockage to left-turn vehicles by through traffic, particularly at an intersection with a short left-turn bay. During the peak hour, some vehicles on the through lane might not be able to depart at the end of a cycle, resulting in an increased probability of left-turn blockage. In turn, the blocked left-turn vehicles may also delay the through traffic to enter the intersection during the following cycle. Those problems may not exist for a lagging left-turn operation, since left-turn vehicles intend to spill out of the bay under heavy traffic. In this case, the through capacity is reduced, leading to an increase of total delay. All of these factors contribute to the difficulties of estimating the delay and capacity for an isolated intersection. In order to examine this missing part of study on the signalized intersection, two probabilistic models are proposed to deal with the left-turn bay blockage and queue spillback in a heuristic manner. Numerical case studies are also provided to test the proposed models. The second part of this research studies an isolated intersection with vehicle-actuated signal. Typically an advanced detector is located at a distance prior to the intersection such that an arriving vehicle triggers a green time extension in or- der to pass through without any stop. This extended time period actuated by the vehicle is called unit extension in this study. If no vehicle actuation occurs during a unit extension, the green phase would terminate in order to clear queues in other approaches. In this way, the actuated system dynamically allocates the green time among multiple approaches according to vehicle arrivals. And the unit extension is the only control parameter in this case. We develop a model to study the vehicle delay under a general arrival distribution with a given unit extension. Our model allows optimizing the intersection performance over the unit extension. The third part of this research applies graphical methods and diffusion approximations to the traffic signal problems. We reinterpret a graphical method which is originally proposed by Newell in order to directly measure the variance of the time for the queue clearance at a signalized intersection, which remains yet to be carefully examined in practice and would be rather challenging if only using the conventional queuing techniques. Our results demonstrate that graphical method explicitly presents both the deterministic and stochastic delay. We also illustrate that the theoretical background for the graphical methods in this particular application is inherently the diffusion approximation. Furthermore, we investigate the problems of disruptions occurred during a pre-timed traffic signal cycle. By diffusion approximation, we provide quantitative estimation on the duration that the effects of disruptions would dissipate.

Page generated in 0.057 seconds